Flashcards in Cardio/Renal Deck (363):
Drug added to regimen for stable angina (with atenolol and aspirin) causes hypotension and bradycardia. What drug was it?
Non-hydropyridine CCB (verabamil, diltiazam) --> additive negative chronotropic effects (slows HR) when combined w/ b blocker
5 groups of drugs w/ negative chronotropic effects (slow HR)
cardiac glycoside (digoxin)
amiodarone and sotalol
Graph showing dissociation of described class I antiarrhythmics being faster than quinidine. What could that antiarrhythmics be?
Class IB so lidocaine or mexiletine
This is because Na+ channel binding strength for class I antiarrhythmics is IC > IA > IB, so IB dissociates fastest
IC dissociates slowest, so it demonstrates most "use dependence" (higher rates of depolarization leads to increased Na+ channel blockade)
What's a coronary steal? What drugs do this? And what do you wanna chieve instead?
In ischemia, collateral circulation maintains perfusion to areas distal to occluded vessel
Drugs that cause CORONARY ARTERIOLAR dilation exacerbate ischemia by causing the already well-perfused vessels (nonischemic) to dilate and steal blood from that collateral circulation
Adenosine and dipyridamole (selective vasodilators) do this
What you wanna achieve instead in this scenario is systemic venous & arterial dilation
Microelectrodes placed in cardiac muscle cells detect rapid decrease in cytoplasmic calcium level immediately preceding relaxation. What mediates this?
Na+/Ca2+ exchange mechanism (sarcolemmal, doesn't need ATP)
The answer is NOT calmodulin, which stimulates plasma membrane Ca2+-ATPase (indirect contributor of efflux)
NE administered to correct hypotension. What's the cellular/messenger changes?
Increase in cAMP in CARDIAC MUSCLE CELL (B1 receptors work thru increase in cAMP)
NOT cAMP increase in vascular smooth muscle cell, whose a1 receptors work thru increase in IP3 (and DAG)
NOT cAMP increase in bronchial smooth muscle cell, whose b2 receptors aren't stimulated by NE
a2 receptor works thru decrease in cAMP (decreases NE release and insulin release)
Where are the 3 leads of biventricular pacemakers?
1) RA (from -> SVC -> RA)
2) RV (same as 1)
3) Left ventricular coronary sinus, which lies in the artrioventricular groove in the posterior aspect of the heart (from left subclavian -> SVC -> RA -> coronary sinus ostium -> left ventricular coronary sinus -> lateral tributaries to regulate LV)
What class of drugs is CI in low level C1 esterase inhibitor?
ACEi (side effect of angioedema from bradykinin accumulation)
Low level of C1 esterase inhibitor -> hereditary angioedema (AD condition)
C1 esterase inhibitor normally inhibits classical complement pathway and kallikrein (normally kallikrein increases bradykinin level by converting it from kininogen)
Pt w/ preexisting atherosclerotic plaque. What increased intraplaque activity will predispose to MI?
Metalloproteinases (destabilizes fibrous cap by degrading collagen)
Get a rise in creatinine after starting ACEi. What structure is involved?
B/c ACEi reduces Ang II, which normally constricts efferent arteriole and thus increases GFR
If less Ang II, GFR decreases
What are the 4 components of crescent formation in RPGN?
1) Fibrin - essential pathologic step, shows up on IF
2) Plasma protein (C3b, NO C4)
3) Parietal cells
4) Monocytes & macrophages
A substance inhibits glucose carrier in proximal tubule. Glucose clearance will now resemble the clearance of what substance?
Inulin, because its filtered amount is now equal to the excretion amount (glucose is not reabsorbed or secreted anywhere else)
Inulin is freely filtered and neither reabsorbed nor secreted = so approximate GFR
What heart sounds are you trying to listen to in LLD position?
S3, S4, MS
What maneuvers make S3 easier to hear?
Make pt fully exhale while lying LLD -> heart closer to chest wall b/c of decreased lung volume
What does use-dependence mean in the context of antiarrhythmics? What's reverse use-dependence?
Use-dependence: effects exaggerated with increased HR -> Na+ channel blockers, esp class IC (flecainide and propafenone) -> QRS interval more prolonged w/ increased HR
Reverse use-depdendence: effects exaggerated with decreased HR -> class III antiarrhythmics (K+ channel blockers - amiodarone, ibutilide, dofetilide, sotalol) -> QT interval more prolonged w/ slower HR
What antiarrhythmic drug prolongs QRS interval during immediate recovery period after stress test?
Flecainide and propafenone (class IC aniarrhythmics) -> strongest use-dependence (the higher the HR, like immediately after exercise test, the more prolonged QRS)
What nitrate agent has the highest bioavailability PO?
Isosorbide mononitrate (metabolite of isosorbide dinitrate)
Both nitroglycerin and isosorbide dinitrate undergo extensive 1st pass in liver
Muffled heart sounds
32-yo healthy male passed a stone in his urine. What abnormalities are you likely to find in his blood and urine?
Normocalcemia and hypercalciuria -> bc calcium stone is the most common kidney stone and it's idiopathic hypercalciuria half the time
3 ways to get normocalcemia and hyperoxaluria?
Diets high in oxalate such as chocolate, nuts, spinach
Diets low in calcium (so more free oxalate around)
Crohns and other intestinal malabsorptions
How do you get normouricemia w/ hyperuricosuria? How about hyperuricemia w/ hyperuricosuria?
High protein diet
If high both in blood and urine, it's something more systemic (tumor lysis, myeloproliferative disorders, gout, lesch-nyhan, etc)
What are the characteristics of PSGN deposits under EM?
subEPITHELIAL deposits of immune complex -> lumpy bumpy IgG, IgM, C3 along GBM and mesangium
How do you prevent paradoxical increase in MVO2 demand when using nitrates?
Prescribe B-blocker w/ it (prevents reflex tachycardia) -> prevents catecholamine from stimulating B1 receptors on myocardium -> slows conduction thru AV node & cardiac conduction system in general
How does chronic kidney disease result in increased bone resorption?
By decreasing phosphate excretion -> more phosphates complex w/ calcium -> body thinks you're low on serum calcium and starts producing more PTH -> "renal osteodystrophy" -> bone pain/osteopenia/sign of soft tissue calcification on X-ray
Also by decreasing calcitriol (less a1 conversion of vit D)
What's Kussmaul's sign? What 5 conditions do you see this?
Paradoxical increase in jugular venous distension/pressure during inspiration (normally would decrease it)
Seen in chronic pericarditis, restrictive CM, right sided HF, tricuspid stenosis, cardiac tamponade
What's pulsus paradoxus? What 5 conditions do you see this?
Drop of systolic BP of more than 10 mmHg during inspiration -> this is because inspiration increases venous blood return resulting in increased right heart volume, which normally doesn't affect the left heart much because your RV can expand into pericardium; in certain diseases (below) where pericardium can't expand, increasing RV volume results in interventricular septum being pushed towards the left and reducing left heart diastolic volume & SV -> so get exaggerated decrease in BP during inspiration
Seen in cor pulmonale, constrictive (chronic) pericardial disease, cardiac tamponade, severe obstructive lung disease (incl acute asthmatic episode!), restrictrive cardiomyopathy
What setting do you see acute cor pulmonale? Chronic?
Asthma - acute
COPD - chronic
What's pericardial knock? What 1 condition do you see this ?
Brief diastolic sound right after S2 (may be confused w/ the opening snap of MS)
Seen in constrictive (chronic) pericarditis
Give characteristics of multicystic kidney dysplasia
Multiple cysts of varying sizes + absence of normal pelvocaliceal system (atresia)
So can dx this in newborns
Give formula for MAP, CO and SV
MAP = CO x SVR
CO = HR x SV
SV = EDV (preload) - ESV
Compensatory mechanisms in acute and chronic AR to maintain CO
AR is the state of volume overload
So to fix this, initially, body increases HR (tachycardia; CO = HR x SV)
Sustained response however is increase in preload (thus increase in SV)
Tx of acute severe AR?
Dopamine or dobutamine (IV inotropic agent)
Pt w/ isolated systolic HTN was put on med that resulted in peripheral edema and flushing. What's the med?
Dihydropyridine CCB (so amlodipine)
1st line drugs for isolated systolic BP are dihydropyridine CCB (so NOT verapamil, etc), and thiazides, but thiazides don't create flushing and edema
What do you prescribe with niacin (nicotinic acid) to prevent facial flushing and warmth?
What molecules play the most significant role in regulating coronary blood flow?
NO (from arginine + O2) - major regulator of flow-mediated vasodilation in large arteries and pre-arteriolar arteries
Adenosine (from ATP metab) - major vasoconstrictor in small coronary arterioles
Nervous input (NE and ACh) has very little effect on coronary blood flow
Triad found in cardiac tamponade
Beck's triad: JVD (distended neck vein), hypotension, muffled heart sound
In addition, might find pulsus paradoxus and tachycardia
Came into hospital for muscle pain, fatigue, and dark urine. Current meds are metoprolol, atorvastatin, aspirin. Now having kidney failure. What was prescribed?
Erythromycin (or any other macrolides except azithromycin) b/c macrolides inhibit P450, leading to increased statin level -> increased risk of rhabdomyolysis -> kidney failure
Differentiate between 4 causes of hematuria post-infection
1) HUS: follows diarrheal infection (E. coli) -> additional sx of conjunctival pallor from microangiopathic hemolytic anemia
2) PSGN: follows pharyngeal/skin infection (strep) -> additional sx of edema, HTN, proteinuria, low C3, but no anemia
3) HSP (IgA deposition vasculitis, see increased IgA): follows URI -> additional sx of palpable purpura , athralgia
4) Berger disease (IgA nephropathy): HSP without extra-renal sx, distinguish from PSGN by IgA MESANGIAL deposits, normal C3 level, and the fact that it takes 2-3 days to develop rather than 2 weeks like PSGN
What's a Korotkoff sound? In what context might you see this used?
Blood flow sound when taking blood pressure
Used in the context of pulsus paradoxus
Take down BP when you first hear this sound during expiration as the cuff pressure is gradually reduced from above systolic BP
Then take down BP when you hear this sound during all phases of respiration
If the difference between the 2 values is > 10 mmHg -> "pulsus paradoxus"
Unequal pulse strength in extremities. What do you have to suspect?
Acute aortic dissection (impaired blood flow past dissection) -> widened mediastinum and abnormal cardiac contour in the setting of HTN or Marfan
What 2 pressure values should be equal during normal diastole?
LA end diastolic pressure and LV end diastolic pressure (if unobstructed mitral valve)
What 2 pressure elevations would you get in dilated & restrictive cardiomyopathy & cardiac tamponade?
PCWP (LA end diastolic pressure), LVEDP (LV end diastolic pressure)
Both values will be approximately equal
How do you decrease RPF and increase FF?
Constricts EFFERENT arteriole
FF = GFR/RPF
What molec estimates RPF? How do you calculate RBF if you know RPF?
PAH clearance (both filtered and actively secreted)
RBF = (PAH clearance) / (1 - hematocrit)
What molec estimates GFR?
Inulin clearance (freely filtered and neither reabsorbed nor secreted)
What parameter is equal between the systemic and pulmonary circulations? What parameters are different?
Equal: blood flow per minute -> both at rest and exercise -> b/c we always have LV output equaling RV at all times!
Parameters that are higher in systemic than pulmonary: MAP, diastolic arterial pressure, systolic arterial pressure (aka "driving pressure for blood flow")
3 antiarrhythmics that can cause AV block?
Drugs that prolong PR interval!
CCBs (verapamil, diltiazam)
So if picking between these two given the side effect, pick CCBs in pts w/ COPD or asthma (b/c we know those pts can't use nonselective B-blockers due to potential exacerbation)
Lymph drainage for bladder?
Upper half -> internal iliac nodes
Lower half -> external iliac nodes
Most common cause of death due to MI during pre-hospital phase? In-hospital phase?
Pre-hospital: SCD (sudden cardiac death = w/in 1 hr) from ventricular arrhythmias
In-hospital: ventricular failure (cardiogenic shock)
What would MI look like on CO (y) vs. right atrial pressure (x) graph and venous return (y) vs. end diastolic volume (x) graph?
It would cause isolated decrease in CO w/out any changes in venous return
What would anaphylaxis look like on CO (y) vs. right atrial pressure (x) graph and venous return (y) vs. end diastolic volume (x) graph?
Significant drop in venous return graph b/c of widespread venous and arteriolar vasodilatation + increased capillary permeability
How do you explain the fact that PAH extraction ratio decreases progressively as the PAH plasma conc goes up beyond a certain threshold value?
PAH gets into urine thru 2 processes:
Filtration: as a general rule, NOT a process that can be saturated b/c it's not enzyme/protein mediated, so if this were the only process involved, extraction will linearly go up as plasma conc goes up
Secretion (in PCT): CAN be saturated b/c there's a transport maximum of secretion enzyme -> above this secretion plateaus
So at conc above this transport maximum, any increase in urine PAH conc (which will go up more slowly than before) is due to increased filtration alone
Can excretion be saturated?
No, excretion is Filtration + Secretion - Reabsorption -> filtration can't be saturated (not enzyme/protein mediated) so excretion can't be saturated either
Both secretion and reabsorption can be saturated tho
Started on new med for HTN that causes increase in creatinine and potassium. What's the med?
Increase in creatinine comes from decrease in GFR (because now there's less Ang II around to constrict efferent arteriole and cause increase in GFR)
What does chronic renal failure do to the level of phosphate?
DON'T think of it as losing vit D means losing phosphate reabsorption ability, instead think of it as renal failure impairs excretion of phosphorus (so totally separate from what happens to vit D level)
Where's the receptor for aldosterone? What are the channels it upregulates?
Cytosol (aldos freely crosses cell membrane to bind the receptor)
Increases # of Na+/K+-ATPase and Na+ channels in principal cells (collecting duct)
Promotes H+ secretion from intercalated cells (collecting duct)
What's the mechanism behind podocyte damage in MCD?
Primary defect in immunologic fx -> overproduction of cytokine (possibly IL-13) -> direct damage to podocyte
What's the mechanism behind podocyte damage in MCD?
Primary defect in immunologic fx -> overproduction of cytokine (possibly IL-13) -> direct damage to podocyte
Hearing loss + ocular abnormalities + hematuria?
Alport syndrome: defect in formation of type 4 collagen -> thinning of GBM
Differences of urinary protein loss in MCD and other nephrotic syndromes (membranous nephropathy, FSGS)
MCD: selective loss of albumin (small molecs)
Sign that you have upper UTI rather than lower UTI?
WBC casts (only formed in tubules, where they're precipitated by Tamm-Horsfall protein secreted by tubular epithelial cells) -> pathognomonic for acute pyelonephritis (unless it's presented w/ low-grade fever and NO painful urination -> then consider acute interstitial nephritis)
Suprapubic pressure more specific to cystitis than urethritis
Principle behind normal anion gap metabolic acidosis?
Loss of bicarb (prolonged diarrhea, etc)
Primary cause of isolated systolic HTN?
Age-related decrease in compliance of aorta and its major branches
Things you can derive from shape changes in pressure-volume loop?
Contractility: slope of line drawn from 0,0 to left upper corner of new graph (steeper -> higher contractility)
Afterload change: peak bump of new graph minus peak bump of old graph
Preload change: how far to the right the new graph is
SV change: width of the graph
LV compliance: unchanged if the bottom lines of the graphs line up
What does nitroprusside do to afterload, preload, contractility, and SV?
Decrease both afterload and preload (it's a vasodilator of both veins and arteries)
Doesn't change contractility or SV
What metabolic abnormality does overuse of diuretics produce? What's the mechanism behind that?
Metabolic alkalosis (contraction alkalosis)
This is b/c vol contraction is sensed by macula densa -> renin and aldosterone out -> low K+ and low H+ now
When do you see HTN and hypokalemic pts w/ low renin and low aldos (4)? Low renin and high aldos (2)? High renin and high aldos?
Low renin & aldos: non-aldosterone causes -> CAH, adrenal tumor producing deoxycorticosterone, Cushing syndrome, exogenous mineralocorticoids
Low renin & high aldos: primary aldosteronism -> Conn's syndrome, bilateral adrenal hyperplasia
High renin & aldos: 2ndary aldosteronism -> things that full kidney into secreting renin -> renovascular HTN (renal artery stenosis assc. w/ fibromuscular dysplasia or atherosclerosis), diuretic use, malignant HTN (leading to microvascular damage and ischemia), renin-secreting tumors (juxtaglomerular cell neoplasm)
Mtral regurg (character, maneuvers, presenting sx)
Character: holosystolic, high-pitched blowing, radiates to axilla
Maneuvers that enhance: handgrip (increases SVR), squatting (increases venous return)
Presenting sx: dysphagia (blood pools in LA)
Tricuspid regurg (character, maneuvers)
Character: holosystolic, high-pitched blowing, radiates to right sternal border
Maneuvers that enhance: inspiration
Aortic stenosis (character, maneuvers, presenting sx)
Character: crescendo, decrescendo systolic, radiates to neck, pulsus parvus et tardus (small and slow rise in carotid pulse during systole) -> listen at cardiac "base"
Maneuvers that enhance: rapid squatting (increases venous return)
Presenting sx: syncope, angina, dyspnea on exertion -> can feel systolic vibrations or carotid shudder (thrill)
VSD (character, maneuvers)
Character: holosystolic, harsh-sounding at tricuspid area
Maneuvers that enhance: handgrip (increases SVR)
Mitral valve prolapse (character, maneuvers)
Character: late systolic crescendo after midsystolic click (sudden tensing of chordae tendineae)
Maneuvers that enhance: intensity increases w/ handgrip and rapid squatting, midsystolic click happens earlier w/ valsava and standing
Aortic regurg (character, maneuvers, presenting sx)
Character: high-pitched blowing early diastolic decrescendo, HEAR AT LSB, wide pulse pressure
Maneuvers that enhance: handgrip (increases SVR) -> vasodilators decrease intensity
Presenting sx: head bobbing, bounding pulses ("water-hammer pulses")
Mitral stenosis (character, maneuvers, presenting sx)
Character: delayed rumbling diastolic murmur after opening snap (from abrupt half in leaflet motion) -> the earlier the OS, the worse the condition
Maneuvers that enhance: expiration
Presenting sx: dysphagia, hoarseness
PDA (murmur character)
Continuous machine-like murmur loudest at S2
Phase 0-4 of ventricular AP and ion channels involved?
Phase 0: rapid depol from incoming Na+
Phase 1: initial repol from outgoing K+
Phase 2: plateau from incoming Ca2+ balancing outgoing K+
Phase 3: rapid repol from outgoing K+
Phase 4: resting potential from leak currents (dominated by K+ permeability)
Phase 0, 3, 4 of pacemaker AP and ion channels involved?
Phase 0: rapid depol from incoming Ca2+
Phase 3: rapid repol from outgoing K+
Phase 4: slow diastolic depol from incoming Na+ (funny current) -> slope of this phase determines HR (ACh and adenosine decrease this whereas catecholamines increase it)
What does P wave on ECG correspond to?
What does PR interval on ECG correspond to? What's the normal value?
Conduction delay thru AV node
What does QRS complex on ECG correspond to? What's the normal value?
Ventricular depol (masking atrial repol) -> phase 0 of ventricular myocyte AP
(so prolonged w/ abnormal foci, LBBB/RBBB, fascicular block, pacemakers)
Bundle branch conductivity determines duration of QRS complex!
What does QT interval on ECG correspond to? What does it approximate?
Mechanical contraction of ventricles
Approximate AP duration -> this is why class IA and III antiarrhythmics predispose you to QT prolongation (they both increase APD)
What does T wave on ECG correspond to?
Inversion - recent MI
What does U wave on ECG signify?
2 congenital long QT syndrome? What does it involve?
Romano-Ward syndrome: AD, no deafness
Jervell and Lange-Nielsen syndrome: AR, + sensorineural deafness
Both involve mutations in K+ channel proteins
Cushing rxn triad?
HTN, bradycardia, resp depression
From increased ICP constricting arterioles -> reflex sympa increase in perfusion pressure -> HTN -> increased stretch -> reflex baroreceptor induced-bradycardia
What would RPF, GFR, and FF look like in pt who lost a lot of fluid thru diarrhea and vomiting?
Losing fluid would result in decreased RPF and GRF, but GFR decreases to a lesser degree b/c your body can actually compensate thru making Ang II to constrict efferent arteriole -> so you end up having increased FF (b/c FF = GRF/RPF)
Differences in complications and causes of chronic mitral regurg vs. acute mitral regurg?
Chronic MR (from myxomatous degeneration or MVP): increased LA compliance, prone to A-fib and mural thromboembolism
Acute MR (from infective endocarditis, chordae tendineae rupture, ischemia, papillary m. rupture, prosthetic valve failure): near-normal LA compliance, prone to marked pulm HTN and pulm edema
What does TdP look like on ECG?
polymorphic QRS complex of varying amplitude and cycle length -> looks like it twists around ECG baseline
What's the most common predisposition to native valve bacterial endocarditis? And what's one way bacterial endocarditis can present?
MVP (esp in 15-60 yo)
If older than 60, consider calcification of mitral annulus (esp w/ prior myxomatous degeneration and chronically elevated LV pressure)
Can present as sign of stroke (throwing clots up the brain) + fever
3 embryonic vein systems and what they become in adults
1. umbilical vein: degenerates (ligamentum teres hepatis)
2. vitelline vein: portal vein system
3. cardinal vein: systemic circulation (SVC)
What is ascending aorta derived from? Descending aorta?
Asc. aorta: truncus arteriosus
Desc. aorta: fusion of right and left dorsal aorta
3 things on ECG in WPW syndrome
Wider QRS complex -> later converted to narrow QRS during tachyarrhythmia b/c accessory pathway no longer pre-excites ventricles but instead forms re-entrant circuit back to atria
4 cardio/resp things that exercise affect?
1. Increases CO
2. Increases preload: from increasing contraction of venous system -> increased venous return
3. Increases contraction of arterioles in all tissues except actively working muscles
4. Decreases afterload: adaptive decrease in SVR (so decreases LV end SYStolic volume) -> why exercising results in only minor increase in BP (should have been a more drastic increase if based on 1-3 alone)
5. LV end-diastolic pressure remains unchanged (increased CO cancels out decreased SVR)
What's the cell of origin of clear cell renal carcinoma? Where does it like to met?
"Hypernephroma" = renal cell carcinoma
Proximal renal tubular epithelium -> golden-yellow grossly from lots of glycogen and lipid
Most common site for mets is lung
What is renal oncocytoma and what's the cell of origin?
Renal oncocytoma: large, well-differentiated, contains numerous mitochondria
Collecting duct cells
Dx of multifocal renal papillary tumors composed of urothelium supported by thin fibrovascular stalk?
Transitional cell carcinoma
3 cardiac abnormalities assc. w/ DiGeorge?
Think of things involving outflow tract. Examples are
Tetralogy of Fallot
Interrupted aortic arch (more extreme version of coarctation of the aorta)
Common cause of hypersensitivity myocarditis? What do you see under microscope?
Starting a new drug -> see perivascular infiltrate w/ abundant eosinophils
What 2 conditions cause increase in serum osmolarity and decrease in both ICF and ECF ("hyperosmotic vol contraction")?
DI, profuse sweating
What 2 conditions cause decrease in ECF and no change in ICF and serum osmolarity ("isosmotic volume contraction")?
Acute GI hemorrhage, diarrhea
What condition causes decrease in ECF and serum osmolarity and increase in ICF ("hyposmotic volume contraction")?
What condition causes increase in ECF and serum osmolarity and decrease in ICF ("hypertonic volume expansion")?
Infusion of large amount of hypertonic saline
What 2 conditions cause increase in ECF and ICF and decrease in serum osmolarity ("hyposmotic volume expansion")?
SIADH, primary polydipsia
% of K+ along the length of kidney tubule
Glomerulus: 100% (all K+ filtered)
PCT: 65% reabsorbed, leaving 35% in tubule -> fixed
Thick asc limb of loop of Henle: another 25-30% reabsorbed (thru NKCC2), leaving 5-10% in tubule -> fixed
Collecting tubules: where regulations of K+ occurs -> principal and a-intercalated cells have final say in how much K+ ends up in pee (can actually excrete more K+ than what's filtered in high dietary intake state)
4 things that increase K+ excretion
High extracellular K+
Things that cause increased fluid flow -> vol expansion, high Na+ intake, diuretic use (thiazide and loop)
4 things that can result in renal papillary necrosis? What causes the sx?
Sickle cell disease
Analgesic nephropathy (phenacytin, NSAIDs)
Acute pyelonephritis and UTO -> compresses medullary vasculature and predisposing to ischemia
What's causing the sx is sloughed papillae obstructing ureter
What vasculitis do you see transmural inflammation of arterial wall w/ fibrinoid necrosis? What's the disease assc.?
PAN (polyarteritis nodosa) -> assc. w/ HBV
Can see this in vessels of any tissues but lungs!
What cell is DIRECTLY responsible for intimal thickening in atherosclerosis?
Medial SMC -> summoned to intima and is directly responsible for reactive intimal hyperplasia and collagen deposition
Cutoff value for micro/macroalbuminemia? When can you detect with dipstick urinalysis?
Microalbuminuria: 30-300 mg/day
Macroalbuminuria: > 300 mg/day -> detected by dipstick urinalysis
4 diseases that can cause myocardial fibrosis?
What's the pathogenesis of vegetations assc. w/ bacterial endocarditis?
Fibrin and platelet deposition
NOT WBC infiltration (even if it's staph aureus)!
Auscultatory indicator of how bad mitral stenosis is?
A2-OS interval -> the narrower, the more severe
Will also hear diastolic rumbling and presystolic accentuation (from LA contraction) -> but these correlate poorly w/ severity
The ABSENCE of presystolic accentuation might signify that MS becomes severe enough to precipitate A-fib (b/c atrial contraction is what causes pre-systolic accentuation in MS)
What 2 info should you gather in metabolic alkalosis?
Urine chloride and volume status
If low urine chloride -> think vomiting, nasogastric aspiration, PRIOR diuretic use -> these are saline-responsive
If high urine chloride -> assess volume status ->
If hypervolemia, consider excess mineralocorticoid activity (Conn syndrome, Cushing disease, ectopic ACTH) -> NOT saline responsive
If hypovolemia or euvolemia, consider CURRENT diuretic use (saline-responsive), or Bartter&Gitelman syndromes
What class of anti-lipid drug should you always think about starting when pt had previous atherosclerotic cardiovascular disease regardless of lipid levels?
Don't care if low HDL, high TG, etc -> this is the only class that proves beneficial to this pt population
2 pathways HDL delivers cholesterol to liver?
Direct: uses SCARB1 (scavenger receptor) on hepatocytes
Indirect: cholesteryl ester transfer protein transfers cholesterol from HDL to LDL and VLDL
CXR finding on acute LV failure?
Cardiomegaly, pleural effusion, Kerley B lines (represent edema of interlobular septa), increased vascular shadowing
What kind of heart dysfx do viral myocarditis and cardiotoxic agents (incl alcohol and chemo agents) cause?
Dilated cardiomyopathy -> predominant systolic dysfx -> so get increase in both end-diastolic volume (preload) and end-systolic volume
What does Wilms tumor resemble under LM?
Primitive metanephric tissue
Given inulin clearance and substance's plasma conc and tubular reabsorption rate, how do you calculate excretion rate?
Excretion = Filtration - Reabsorption
Reabsorption rate given, so calculate filtration rate by multiplying inulin clearance (representing GRF) by substance's plasma conc, then plug that into the equation
Most common cause of aortic stenosis in older pts and its pathogenesis?
Age-related calcific aortic stenosis (the benign version of this is called "aortic sclerosis")
From cell necrosis (2ndary to chronic hemodynamic stress or atherosclerotic inflammation) -> dystrophic calcification
What nephron segment responds to ADH by increasing absorption of ammonia to maintain high medullary conc gradient?
Medullary collecting duct -> ADH increases # of passive urea transporter -> urea go reabsorbed and go to the thin asc. loop of Henle -> urea allowed to recirculate and further concentrate
Urea also reabsorbed at PCT, but here ADH doesn't play any role
How do you prevent acyclovir-assc. crystalluria?
Aggressive IV hydration and dosage adjustment (infuse slower)
Main compensatory mechanism responsible for why you don't get peripheral edema w/ some ppl w/ right HF?
Increased lymphatic drainage -> compensates for increase in interstitial fluid up to a point
What abnormalities would you see w/ drug-induced acute interstitial nephritis? What 4 drugs commonly cause this?
High serum eosinophils and IgE, granuloma formation
Beta lactams, diuretics, NSAIDs, anticonvulsants
What does bulbus cordis become?
Ventricular outflow tract -> smooth part of ventricles adjacent to pulm artery/aorta
What does sinus venosus become?
Smooth part of RA (sinus venarum) -> receives blood from vena cavae
What structure is ductus arteriosus derived from?
6th aortic arch
What's the pathogenesis of supine hypotension syndrome in pregnant women > 20 wks?
Compression of IVC by gravid uterus during supine -> so less venous return -> less CO -> hypotension and syncope
What happens to pressure-volume loop w/ AVM?
You're bypassing arterioles (source of greatest resistance) -> decreases TPR -> so get lower afterload
Also get increased preload
So high volume shunt can cause high-output cardiac failure
Diff bet. xanthoma and xanthelasma?
Xanthoma: benign foamy macrophages (containing TG, cholesterol, phospholipids) surrounded by inflammatory cells and fibrotic stroma
Xanthelasma: no inflammatory cells or fibrotic stroma
Most common cause of unilateral fetal hydronephrosis?
Obstruction at ureteropelvic jx (so bet. kidney and ureter) -> metanephros begin producing urine before ureteric bud canalization is complete (the jx is the last segment of ureter to canalize)
3 precipitating factors for isolated episodes of AF?
Binge alcohol consumption (holiday heart syndrome)
Increased cardiac sympathetic tone
EKG for A-fib?
Absent p waves
Variable R-R interval (irregularly spaced ventricular contractions)
What is high QRS voltage in precordial leads a sign of?
What does prolonged QRS complex mean?
Ventricular dyssynchrony or slowed intraventricular impulse conduction -> BBB is a common cause
2 sx of Conn's syndrome (too much aldos) precipitated by hypokalemia?
Muscle weakness (from hypokalemic paresis) and paresthesias (from hypokalemic alkalosis)
What can vesicoureteral reflex be a complication of? What 2 things does it predispose to?
Prostatectomy or bladder surgery
Predisposes to pyelonephritis and hydroureteronephrosis
Besides inhibiting NKCC2, what else does loop diuretics do?
Stimulate prostaglandin release -> increases renal blood flow -> increased GFR and enhanced drug delivery
So decreased response is assc. w/ NSAIDs use
What cells produce endothelin?
What happens to renin, Ang I, Ang II, aldos, and bradykinin after starting ARB?
No ARB stimulation means decreased aldosterone w/ no change on bradykinin
Starting ARB also means less AT-1 receptor (Ang II receptor) stimulation -> less negative feedback regulating RAAS -> increases renin -> increases Ang I -> increases Ang II
What does positive urinary cyanide-nitroprusside test dx of?
AR defect of renal PCT and intestinal AA transporter for COLA (Cysteine, Ornithine, Lysine, Arginine) -> cystine stones
Risk factors of transitional cell carcinoma? What do you see on cystoscopy?
Risk factors: smokers, occupational exposure to rubber, plastics, aromatic amine-containing dyes, textiles, leather
On cystoscopy: see multifocal sessile or papillary tumors
What sign indicates glomerular bleeding source besides RBC cast?
What vessel has the highest O2 extraction?
Coronary vessels -> so see the most difference bet. the arterial and venous side
This means blood oxygen content here will differ most from aorta (don't even see that degree of difference in pulm artery b/c even the deoxygenated systemic blood returning via SVC and IVC has more O2 content than coronary venous blood)
Why are you more prone to hyponatremia w/ thiazide diuretics compared to loop diuretics?
Loop inhibits solute absorption in thick asc limb of Henle -> this portion is important to corticomedullary conc gradient -> so can't concentrate urine in loop and lose lots of BOTH salt and water in urine
Thiazide inhibits at a diff place -> so normal corticomedullar conc gradient -> better able to retain water in response to increased ADH -> so lose more salt than water -> hyponatremia
What are Aschoff bodies? What condition do you see them in?
Aschoff bodies: interstitial myocardial granulomas, might see Anitschkow cells (caterpillar cells; macrophages w/ round nuclei w/ central slender chromatin ribbons)
See this in acute rheumatic fever (which is preceded by group A strep pharyngitis by 10 days to 6 wks)
Mechanism behind diphtheritic myocarditis?
Circulating toxin produced by tonsillopharyngitis (primary focus of infection in upper aerodigestive tract)
See pleomorphic interstitial infiltrate of macrophages
Complication of varicose vein?
Venous stasis ulcers (skin ulcers, usually over medial malleolus) -> erythema and scaling w/ progressive dermal fibrosis and hyperpigmentation
What is phlegmasia laba dolens?
Painful white leg as a consequence of venous thrombosis in iliofemoral vessel
Seen in peripartum women (hypercoagulability + pressure of gravid uterus on deep pelvic veins produces venous stasis)
What do peaks and troughs in JV pressure correspond to?
a wave: atrial contraction (prominent in hypertrohic cardiomyopathy)
c wave: RV contraction, (closed tricuspid bulging into RA)
x descent: RA relaxes (absent in tricuspid regurg)
v wave: RA filling against closed tricuspid
y descent: tricuspid valve opens so blood goes from RA to RV (steeper and deeper w/ constrictive pericarditis)
3 potential causes of constrictive pericarditis?
Radiation to chest
Tuberculosis (suspect in immigrants)
Given conc of inulin and PAH in urine&plasma and urine flow rate, how do you calculate FF?
Clearance = urine conc x urine flow rate / plasma conc
GFR = inulin urine conc x urine flow rate / inulin plasma conc
RPF = PAH urine conc x urine flow rate / PAH plasma conc
FF = GFR / RPF
Prominent sx of myxoma? And what 2 molecules does it produce?
Usually in atria causing valve obstruction -> so if at mitral get position-dependent sx (worsens when sitting and improves when lying down) + low-pitched, mid-diastolic rumble at apex
Migh produce VEGF -> angiogenesis & hemorrhaging (w/ hemosiderin deposition) & friability
Also might produce IL-6 -> constitutional sx
What's the most likely sequelae of congenital bicuspid aortic valve? What condition is assc. w/ this?
NOT AS in infancy -> usually will be asymptomatic (this is unlike congenital AS, whic will present as systolic murmur at birth)
More likely to see AS in their sixties b/c the condition accelerates normal aging process (usually age-related calcific AS happens in 8th-9th decades otherwise)
Bicuspid aortic valve seen in Turner's
Where does obtuse marginal branch come from? What about acute marginal branch?
Obtuse: from left circumflex coronary artery
Acute: from RCA
What wall is the diaphragmatic surface of heart? What artery supplies this?
Inferior wall of LV
Supplied b pos. decending artery (which is usually from RCA)
DOC for paroxysmal SVT?
Adenosine, followed by CCB
What parameter affects the slopes of both venous return and cardiac output curves?
TPR -> increased TPR will result in increased afterload (so reduced CO) and restricts venous return
What deposits do you see in MPGN type 1? Where are the deposits?
What's impaired in FHH (familial hypocalciuric hypercalcemia)? What's the mode of transmission?
Impaired Ca2+ sensing by parathyroid gland and renal tubule cells -> so get hypercalcemia w/ normal-high PTH
Mechanism behind why myocytes swell when ischemic?
No ATP -> membrane Na+/K+ ATPases and SR Ca2+-ATPases don't work -> accumulates Na+ and Ca2+ inside cells -> water follows in
Pt on A-fib and HF tx present w/ n/v, anorexia, confusion, high K+. What's the likely drug?
Digoxin! -> digitalis acts on Na+/K+ ATPase and causes increased K+
But do remember that hypokalemia increases pt susceptibility to toxic effects of digoxin!
3 ways to fix digitalis/digoxin toxicity
1. oral activated charchoal
2. insulin, kayexalate, or hemodialysis to manage high serum K+
3. digoxin-specific Ab fragments
What vasculitides involve granulomatous inflammation of the media?
Giant cell arteritis
What vasculitides involve fbrinoid necrosis of small vessels?
Leukocytoclastic vasculitis (microscopic polyangiitis, microscopic polyarteritis, hypersensitivity vasculitis)
Polyarteritis nodosa (immune complex vasculitis)
Rheumatoid arteritis (hypersensitivity vasculitis)
What kind of mutations cause genetic form of dilated cardiomyopathy?
Mutations affecting cardiac cell cytoskeleton proteins
Mutations affecting mitochondrial enzymes of oxidative phosphorylation
Mutations to what causes congenital QT-interval prolongation?
Cardiac cell K+ or Na+ channels
K+ channel mutation causes decreased outward K+ current
What murmur can disappear w/ A-fib?
They're diastolic murmur w/ presystolic accentuation (due to atrial contraction). W/ mild, murmur may only be audible during accentuation phase in late diastole and might disappear w/ A-fib
2 diuretics affecting loop of Henle and what segments specifically?
Osmotic diuretics (mannitol): DESCENDING limb of loop (on top of PCT)
Loop diuretics: thick ASCENDING limb of loop
Why do you have more chloride in RBC in venous blood than arterial blood?
Increased activity of carbonic anhydrase
More CO2 in venous blood -> carbonic anhydrase works harder -> more HCO3- generated -> more HCO3- diffuse out of RBC into plasma -> more Cl- diffuse into RBC to maintain electrical neutrality ("chloride shift")
This means that if you inhibit CA, you'll get more Cl- accumulation in venous BLOOD (not RBCs)
Layers of things you have to pass thru to go from skin to heart?
Skin -> pectoralis major m. -> external intercostal membrane -> internal intercostal m. -> internal thoracic artery and veins -> transverse thoracis m. -> parietal pleura -> pericardium -> heart
What's the most specific sx of giant cell arteritis?
Formula for ejection fraction?
EF = SV / preload
What is coronary sinus dilation a sign of?
Anything that causes RA dilataion (since coronary sinus communicates freely w/ RA) -> so pul artery HTN for example
Serum abnormalities seen in tumor lysis syndrome?
Hyperuricemia = decreased urine output and elevated BUN and creatinine -> use allopurinol or rasburicase to prevent
Hyperkalemia = arrhythmia
A person undergoing chemo came in third day of tx w/ decreased urine output + peak T wave. What should you suspect?
Tumor lysis syndrome -> decreased urine output from elevated uric acid (DNA breakdown) and peak T wave from high K+
What is S3 a sign of?
Increased LV end-SYSTOLIC volume (increased LV filling rate during mid diastole) -> so pts w/ LV systolic failure, well-trained athletes (from forceful filling), consequence of MR
Why does increasing dopamine conc result in graphs of CO and renal blood flow that start out low, peak, then come back down? And why does epinephrine not do the same thing to renal blood flow?
Low dose: D1 receptors in renal vasculatures and tubules Intermediate dose: B1 receptors increasing CO
High dose: A1 receptors decreasing CO (increased afterload)
Epinephrine can only decrease renal blood flow because it can only affect a1 receptors there
What type of dyslipidemia is seen w/ defects in lipoprotein lipase of ApoC-II?
Familial chylomicronemia syndrome (type I dyslipidemia) -> accumulates chylomicrons and usually present w/ acute PANCREATITIS (xanthelasmas less common compared to familial hypercholesterolemia), lipemia retinalis, marked hyperTG
What type of dyslipidemia is seen w/ defects in LDL receptor or ApoB-100?
Familial hypercholesterolemia (type II dyslipidemia) -> accumulates LDL and usually present w/ premature coronary artery disease + tendon xanthomas + xanthelasmas
What type of dyslipidemia is seen w/ defects ApoE?
Familial dysbetalipoproteinemia (type III dyslipidemia) -> accumulates chylomicrons and VLDL remnants and usually present w/ premature coronary artery disease
What type of dyslipidemia is seen w/ defects ApoA-V?
Familial hypertriglyceridemia (type IV dyslipidemia) -> accumulates VLDL and assc. w/ obesity and insulin resistance (also increased pancreatitis risk)
What do you administer to measure LPL activity?
Heparin -> releases endothelium-bound lipases and allows its activity to be measured
What stimulates chromaffin cells in adrenal medulla?
ACh from sympa neurons!
Remember that it releases E and NE but gotta be stimmulated by ACh
Where do you hear the opening snap of mitral stenosis on the pressure volume loop?
Closest to where the mitral valve opens NOT in the middle bet. mitral opens and mitral closes -> b/c by this point the ventricle has already filled to half
What's the abnormal process in tetralogy of fallot, transposition of great vessels, and truncus arteriosus?
Abnormal migration of neural crest cells thru primitive truncus arteriosus and bulbus cordis
NOT abnormal heart tube looping!
CT shows dissection of both asc. and desc. aorta. What's the single most important risk factor?
Tertiary syphilis only results in asc aortic ANEURYSMS (dissection rare)
How do drugs inhibiting FA oxidation help w/ stable angina?
FA oxidation generates more ATP than glucose oxidation, but it also uses more O2 in the process -> so shifting metabolism to glucose will make energy production more O2 efficient
What does renal failure do to K+ level?
Hyperkalemia from impaired renal excretion
What happens to plasma sodium&osmolarity, urine sodium&conc, body fluid volume in SIADH?
plasma sodium&osmolarity: decreased
urine sodium&conc: increased
body fluid volume: NORMAL (b/c normal fx of aldosterone and natriuretic peptides help alleviates hypervolemia) -> so won't see volume overload sx like lower-extremity edema, bibasillar crackles, or elevated JVP!
What should you think about in hyponatremia w/ urine osmolality
Primary polydipsia (maximally dilute urine)
Which kidney stone is the only one radiolucent?
Uric acid -> so WON'T show up on plain abd films -> use US or CT instead
What vasculitis is assc. w/ antibiotic use? What type of HSR is it?
Microscopic polyangiitis (leukocytoclastic angiitis or hypersensitivity angiitis) -> type III immune rxn
Timeline for what happens to heart when blood flow gets cut off (total ischemia)
W/in 60 sec: stop contracting!
30 min: irreversible
How does angioedema typically manifest?
Rapid-onset swelling of lips and larynx
What does internal hemorrhage (like from trauma) do to kidney? What's the process?
Ischemic ATN! (affects PROXIMAL TUBULES AND THICK ASC LIMB -> don't confuse w/ renal papillae necrosis which is assc. w/ DM, analgesic nephropathy, and SSD) -> 3 phases
2. maintenance (oliguric): can last 1-2 wks and see "muddy brown casts" -> get high anion gap acidosis, low urine osmolarity ( but if it's assc. w/ multi-organ failure, renal fx might be permanently impaired -> see foci of interstitial scarring on LM
What 2 conditions do you see BM splitting in?
MPGN 1 - also see granular deposits on IF
What do you see on LM w/ membranous glomerulopathy? IF?
LM: diffuse capillary wall thickening
IF: granular deposits of IgG and C3 along GBM (idiopathic membranous nephropathy is assc. w/ IgG4 Ab against PLA2 receptors)
See ventricle myocytes expressing more natriuretic peptides typically synthesized by atria. What's the assc. conditions?
Volume overload or ventricular hypertrophy -> the release of both ANP and BNP increase to facilitate natriuresis and diuresis
Where's the main site of uric acid precipitation in kidney?
Precipitates where it's most acidic! -> so distal tubules and collecting ducts (lowest pH along nephron)
This means risk of tumor lysis syndrome can be reduced by urine alkalinization (on top of hydration & allopurinol)
3 descriptors of chest pain and DD?
Crampy chest pain: DES, unstable angina
Burning chest pain: GERD
Pleuritic chest pain assc. w/ deep breathing: PE
If given a graph of membrane potential (y) vs. time (x), and told that a particular channel opens at one reflection point while another channel opens at another reflection point. How do you tell which kind of channel it is?
Look at equilibrium potential of each ion. For example, EK = -80 mV means if the K+ channels are open, membrane potential will wanna come down to a negative value; ENa = +60 mV means if the Na+ channels are open, membrane potential will wanna go up to a more positive value (regardless of the absolute value shown!) -> then use process of elimination for each choice
Remember that this also depends on which ions are predominant inside (K+) vs. outside (Na+, Cl-) cells -> so since K+ is predominant inside and its equi potential is negative, when the channels open it'll flow OUT to create negative potential on the INSIDE cell. Cl- equi potential is also negative, but it lives outside and has negative charge so when channels open it'll flow IN to create negative potential INSIDE cell.
What's the special sx of inf MI?
Inf MI usually from blockage of right coronary artery -> this also supplies SA and AV nodes so you also get bradycardia
What is differential cyanosis (blue toes but upper extremities are fine) most suggestive of?
PDA that wasn't corrected at birth -> L-R shunted reverted to R-L shunt
NOT coarctation of aorta, which usually presents as BP discrepancy and even if differential cyanosis exists, it's likely to present early and be accompanied by CHF and other things
If administering a particular drug results increased BP (both systolic and diastolic) and reflex bradycardia, what receptor is involved? What's the mechanism behind bradycardia?
a1 stimulation (think phenylephrine, methoxamine)
Bradycardia is from increased BP stimulating baroreceptors -> reflexive increase in vagal influence on heart -> this will decrease everything (HR, contractility, AV conductance)
What can you do to prevent renal stones besides drink a lot of fluid?
Citrate (potassium citrate) -> binds free Ca2+ and prevents precipitation -> facilitates Ca2+ excretion
What renal stones precipitate in acidic pH? Alkaline pH?
Acidic pH: precipitates calcium oxalate, uric acid, cystine stones
Alkaline pH: precipitates calcium phosphate, struvite stones
What's pyogenic granuloma?
A polypoid form of capillary hemangioma (exophytic red nodules attached by a stalkto gingival or oral mucosa or skin) -> usually follows local trauma and resembles hypertrophic granulation tissue
Normal pressures in RA, RV, and pulm artery?
RA: min 0, max 8 mmHg
RV: min 4, max 25 mmHg
Pulm artery: min 9, max 25 mmHg
Normal pressures in LA, LV, and aorta?
LA: min 2, max 12 mmHg
LV: min 9, max 130 mmHg
Aorta: think normal BP -> min 70, max 130 mmHg
Where is renal vein in relation to aorta and SMA?
Ant. to aorta and post. to SMA
What level does aorta & IVC bifurcate?
Where is IVC on abd CT?
Ant. to right half of vertibral bodies
Stop thinking about one of those tubes being esophagus, there's no esophagus in abd wall!
What group of orgs should you be thinking w/ infective endocarditis?
Rarely ever caused by G- (so forget endotoxin if it's ever in the choices)
What's the pathogenesis of acute renal insufficiency assc. w/ bacterial endocarditis?
Circulating immune complexes
Do you get eccentric hypertrophy or concentric hypertrophy of LV in mitral insufficiency?
Eccentric (dilated) from volume overload
What causes type 2 (proximal) renal tubular acidosis?
Impaired bicarb reabsorption (so MM and drug toxicity like acetazolamide)
What's the tubular fluid osmolarity in PCT? Where is fluid most diluted along nephron?
PCT: always isotonic w/ plasma (300 mOsm/L) regardless of what happens to final urine conc
Most diluted in distal tubules (about 100 mOsm/L) if you're in high ADH states (water-deprived), in collecting duct if you're in low ADH states
Chronic renal hypoperfusion will cause hypertrophy and hyperplasia of what cells?
Dx of decreased LV chamber size + sigmoid shaped ventricular septum + myocardial atrophy w/ increased collagen deposition + brownish perinuclear cytoplasmic inclusions?
NORMAL aging heart
Trauma to what rib risks puncturing left kidney?
Tip of 12th rib
What cells release EPO?
Peritubular cells in renal cortex
What's the course of strawberry hemangioma?
Initially increase in size (grow in proportion of child growth) then regress
Mechanism behind diabetic nephropathy?
Hyperglycemia induces ANP -> increased hydrostatic pressure in glomerular capillary, decreased GFR, and glomerular hypertrophy -> compensation of GFR by increasing vol of mesangial matrix and thickening GBM -> over time get nodular diffuse glomerulosclerosis (Kimmelstiel-Wilson)
How do you distinguish bet. complete and partial central DI?
Complete: rise in urine osmolality > 50% after vasopressin administration
Partial: more moderate response
What drugs directly block the lumen of ion channels?
What group of drugs are used in emergent tx of acute coronary syndrome b/c they decrease mortality?
In what condition do you see tubular proteinuria? Selective proteinuria? Overload proteinuria? Functional proteinuria? Orthostatic proteinuria?
Tubular proteinuria: disrupted proximal tubular fx -> like in tubulointerstitial nephritis
Selective proteinuria: minimal change disease
Overload proteinuria: MM
Functional proteinuria: exercise, high fever, emotional stress, cold exposure -> normal renal fx
Orthostatic proteinuria: older, tall, thin adolescents -> normal renal fx
Course of ureter?
Courses UNDER gonadal vessels -> then OVER common/external iliac vessels (which are lateral to it; internal iliac vessels are posteromedial to it) -> then under uterine vessels
Diff in the course of gonadal vessels in male and female?
In both, gonadal vessels cross over ureters
Males: gonadal vessels course around pelvic brim before entering deep ring of inguinal canal -> so actually never enter true pelvis
Females: gonadal vessels are called ovarian vessels, and they go to true pelvis (ureters course medial to them and then under them)
What chamber forms heart apex?
What's the course of pulm artery after it bifurcates?
Right: travels horizontally under aortic arch pos. to SVC
Left: travels superiorly over left main bronchus
The proximal 2-3 cm of what vessels contain cardiac muscle w/in media and fx like sphincters during atrial systole?
What controls ventricular contraction rate in A-fib?
AV node refractory period
B/c ventricular response depends on transmission of abnormal atrial impulses thru AV -> but b/c of refractory period the majority of atrial impulses never reach ventricles
What does it mean that AF begets AF?
A-fib leads to electrical remodeling of atria & shortens refractory periods & increases conductivity -> creation and persistance of multiple ectopic foci and re-entrant impulses w/in atria -> increases risk and chronicity of subsequent episodes
What's the point of nitrate-free period (where you don't take nitrate before you go to sleep at night)?
Avoid drug tolerance!
What side effects should you expect w/ drugs that selectively dilate arterioles but not veins? How do you fix it?
Prototypical drugs: hydralazine and minoxidil
Expect sodium & fluid retention b/c arteriolar dilation stimulates baroreceptor -> reflex sympa -> increased HR, contractility, renin release
Prevented by giving these drugs w/ sympatholytics and diuretics
What is SCC of bladder assc. w/?
Main presenting sx of urothelial (transitional cell) carcinomas?
Painless gross hematuria
What conditions are CI for ACEi?
Bilateral renal artery stenosis (incl pts w/ extensive atherosclerosis who might have this)
This is b/c these pts are dependent on ACE-mediated efferent arteriole constriction to maintain renal perfusion and GFR -> ACEi will take this away -> ARF
What's the first step of atherosclerosis?
Endothelial injury! -> then you get other stuff later (platelet adhesion & macrophages & SMCs)
Most common cause of MVP? Inherited causes?
Most common: sporadic myxomatous degeneration of mitral valve (elongation and redundancy of valve leaflets and chordae tendineae)
Inherited stuff: Marfan, Ehlers-Danlos
Why don't you get rise in serum creatinine as you age even tho your renal fx decreases progressively?
B/c your muscle tissue (lean body mass) also decreases w/ age, and creatinine is derived from muscle tissue
Aorta lying ant. and to the right of pulm artery. Machine like murmur heard. What's the defect?
Septation -> this is transposition of great arteries (w/ open PDA to compensate)
Example of cardiac defect from failed fusion?
Endocardial cushion defect -> ostium primum ASD
Timeline of MI and microscopic changes?
No change seen til 4 hrs after!
1st day: cytoplasmic hypereosinophilia (earliest sign) + edema + coag necrosis + hemorrhage + wavy fibers + marginal contraction band necrosis
1-5 days: neutrophils
5-10 days: macrophages
10-14 days: granulation tissue
> 2 wks: collagen & scars
What should you think about in young pts w/ recurrent nephrolithiasis?
Inborn error of metabolism
Sodium cyanide added to urine followed by sodium nitroprusside -> urine turns red-purple. What does this mean?
Defection of sulfhydryl groups (cyanide converts cystine to cysteine, nitroprusside then binds cysteine and generates purple color) -> so all in all used for detection of cystine in urine (get this in pts w/ cysteine crystal stones)
What should you assc. w/ cystinuria?
Aminoaciduria -> b/c cystinuria results from defect in renal proximal tubules, and cystine transporter also reabsorbs dibasic AAs (like arginine, ornithine, lysine) -> so increased excretion of these AAs (but these aren't what generate stones, cystine is)
Blood supply to the upper ureter? Lower ureter?
Upper 1/3 of ureter: renal artery (why portion of donor ureter is typically viable after renal transplantation) -> this is anastomosed w/ recipient's EXTERNAL iliac artery during transplant
Lower ureter: gonadal and vesical arteries (sup. vesical artery also supplies sup. bladder)
What should you proceed w/ pts w/ evidence of valvular vegetation whose culture kept turning up negative?
Order special serologies and cultures -> esp Bartonella, Coxiella, Mycoplasma, Histoplasma, Chlamydia, HACEK (H. influenzae, Actinobacillus, Cardibacterium, Eikenella, Kingella)
What happens to calcitonin in chronic renal disease?
Increased (even tho you're hypocalcemic) b/c excretion is impaired
What does positive net filtration pressure mean? negative? Where in the body do you see negative filtration pressure?
Positive: favors fluid movement from capillary into interstitium
Negative: opposite -> seen in intestinal wall
Sx of thromboangiitis obliterans (Buerger's disease)? What's unique about this over other vasculitides?
Calf pain + painful ulcers of distal extremities + Raynaud's + IMMUNE SENSITIVITY T TOBACCO SMOKE
Segmental thrombosing vasculitis that extends to contiguous veins and nerves as well (don't see this in other vasculitides)
What condition is pauci-immune RPGN (type 3)? Granular IF RPGN (type 2)? Linear IF RPGN (type 1)?
Type 1: Goodpasture
Type 2: SLE (immune complex mediated)
Type 3: Wegener's (no Ig or complement deposits)
What drugs induce ANCA?
Hyperthyroid meds (propylthiouracil, methimazole)
How does mixed cryoglobulinemia present and what are its disease assc.?
Systemic findings (fatigue, athralgia, myalgia) + PALPABLE PUPURA in lower extremities
Assc. w/ HCV, SLE
How does arterial vasodilator help w/ MR?
Reduces LV afterload -> increase forward-to-regurgitant vol ratio and reduce HF sx
Surgery is the only definitive tx tho
What does ANP do to kidney and adrenal gland?
Kidney: dilates afferent arteriole (thru cGMP), limits Na+ reabsorption in PCT and inner medullary collecting duct, inhibits renin secretion
Adrenal gland: restricts aldos secretion
Diff bet. small vs. large VSD findings?
Small: LOUD holosystolic murmur possibly w/ precordial thrill, normal CXR, ECG -> might be hemodynamically insignificant
Large: softer murmurs (interventricular pressure gradient is smaller)
What maneuvers accentuate systolic ejection murmur of hypertrophic cardiomyopathy?
Anything that decrease preload or afterload -> straining phase of Valsalva, sudden standing, nitroglycerin
Most common cause of abdominal aortic aneurysm?
Atherosclerosis weakening underlying media -> NOT medial degeneration (less common)
Most reliable auscultatory finding indicating high regurgitant volume in MR?
Left-sided S3 gallop
Intensity doesn't correlate well!
Fick principle for calculating CO?
CO = O2 consumption / arteriovenous O2 difference
What drug should be used in HTN pt w/ prolonged AV conduction time?
Nifedipine (dihydropiridines don't prolong AV like other CCBs!) -> very good for HTN pts w/ bradycardia
What happens to GFR, RPF, and FF as you constrict efferent arteriole?
Increased GFR, reduces RPF, and increases FF -> but as constriction continues to increase, GFR begins to decreased from rise in glomerular capillary oncotic pressure; however FF always increases
What happens to GFR, RPF, and FF as you constrict afferent arteriole?
Decreased both GFR and RPF -> no change in FF
What compose right heart border on PA CXR?
Upper border: SVC
Lower border: IVC
Don't think about RV -> it's anterior on PA CXR
How is lipofuscin produced?
By lipid peroxidation
What does acute ureteral constriction/obstruction do to GFR, RPF, FF?
GFR = decreased (from increased glomerular hydrostatic pressure)
RPF = unchanged (in first 12 hrs)
FF = decreased
What happens to EF, LVEDV, LVEDP in isolated diastolic HF? Isolated systolic HF?
Isolated diastolic HF: increased LVEDP, normal EF and LVEDV
Isolated systolic HF: decreased EF, increased LVEDP & LVEDV
What molecules are precapillary sphincters responsive to?
NE and epinephrine (either relax or contract them depending on locations)
Also dilate in response to histamine, low O2, elevated CO2, or decreased pH
What are the most serious complications of ATN in maintenance phase? Recovery phase?
Maintenance phase: hyPERkalemia (fatal arrhythmias)
Recovery phase: decreased conc of K, Mg, PO4, Ca -> but most worrisome is hypokalemia
Why is A-fib particularly dangerous in ppl w/ severe AS or concentric LV hypertrophy?
B/c in those ppl, atrial contraction contributes significantly to LV filling -> no coordinated atrial contraction will acutely reduce LV preload and CO -> dangerous systemic hypotension
What's the most common arrhythmia in ppl w/ no other heart disease? What's the cause and how do you tx it?
Paroxysmal supraventricular tachycardia (PSVT)
Cause: re-entrant circuit in AV node
Tx: adenosine in hospital, vagal maneuvers (carotid sinus massage and Valsalva) outside hospital
EM shows GBM disruptions and fibrin deposition. Dx?
GBM breaks b/c of fibrinoid necrosis of glomeruli, fibrin b/c it escapes into Bowman's space
What exactly is Valsalva maneuver? What does it attempt to do and what muscle is involed?
Forcibly exhale against closed glottis (like you would while you're straining to poop)
Try to increase intraabdominal and intrathoracic pressure
Rectus muscles involved
ST elevation in leads II, III, aVF. What artery is occluded?
ST elevation in leads V1-V4. What artery is occluded?
ST elevation in leads V5-6, I, aVL. What artery is occluded?
ST elevation in all V leads and maybe also I and aVL. What artery is occluded?
Dx of cystic dilatation of collecting ducts + flank pain + hematuria + HTN + liver cysts?
Renal cysts on CT do not enhance (unlike solid mets or malignancies)
Pts of what 3 conditions have the same risk of cardiovascular events (MI, stroke) as pts w/ known coronary heart disease?
Noncoronary atherosclerotic disease
Chronic kidney disease
What happens to mixed venous O2 content in CHF?
B/c less arterial blood is delivered to peripheral tissues -> increased contact of tissues w/ venous blood -> increased O2 uptake
What kind of diet do you recommend in ppl w/ recurrent calcium stones? (besides more fluid intake)
Pyridoxine supplement if calcium stones are assc. w/ hyperoxaluria (B6 decreases endogenous oxalate production)
Most common cause of mitral stenosis? What do you see grossly and what is the complication?
Rheumatic heart disease (following acute rheumatic fever) -> fibrosis of valve leaflets -> atrial enlargement leads to atrial mural thrombosis and embolic stroke risk
Most important prognostic factor in pts w/ PSGN?
Age -> younger has better prognosis
How do CCBs affect SA and AV nodal cells?
Slow DIASTOLIC depolarization (during phase 4, whose rise is later augmented by transient inward Ca2+ current that shoots up to phase 0 once membrane potential reaches threshold)
What antiarrhythmic drugs raise threshold potential of cardiac tissues?
Class I (Na+ blocking): affect fast tissues (myocytes)
Class IV (Ca2+ blocking): affect slow tissues (SA and AV)
What antiarrhythimic drugs increase refractory period?
Class IV (CCBs): in nodal tissues
Class IA and III: from prolonging repolarization
Extra click/sound in 65-yo over apex. MVP midsystolic click or S4?
S4 (always pathologic) -> prob from stiff LV (restrictive cardiomyopathy or LV hypertrophy)
What is the diff in assc. bet. PSGN and acute rheumatic fever (ARF)?
PSGN: can follow pharyngitis OR impetigo
ARF: follows pharyngitis only
When is serum creatinine an insensitive indicator?
When GFR is normal (the right of the graph shows large decreases in GFR resulting in only small increases in serum creatinine)
This is reverse when GFR is significanly decreased (when kidney is doing badly)
How do you get functional MR?
Dilatation of LV in response to increased preload (like pulm edema)
Can be eliminated by preload reduction
What auscultatory finding do you find w/ pulm HTN?
Diff in auscultatory findings in reduced intrinsic ventricular wall compliant (restrictive cardiomyopathy) and extrinsic (constrictive pericarditis)
Intrinsic (restrictive cardiomyopathy): S3
Extrinsic (constrictive pericarditis): pericardial knock (earlier in diastole than S3)
What electrolyte abnormality can cause muscle weakness and paralysis esp. in alcoholics?
What is a bifid carotid pulse w/ brisk upstroke characteristic of?
hypertrophic obstructive cardiomyopathy (HOCM)
bifid carotid pulse w/ brisk upstroke = "spike and dome"
Exact acid-base abnormality in salicylate overdose?
Start w/ resp alkalosis (hyperventilation)
As you progress get mixed resp alkalosis + metabolic acidosis (from its metabolites) -> then more and more metabolic acidosis component as time passes
So if asked about abnormalities about 4-5 hrs after ingestion, ignore pH parameter (could be anywhere), but pick a choice w/ low PaCO2 (resp alkalosis) and low plasma HCO3- (metab acidosis, NOT renal compensation b/c that won't happen in acute setting)
What vasculitides is mononeuritis multiplex assc. w/?
Wegener's and PAN
(mononeuritis multiplex = peripheral neuropathy of multiple individual nerves)
Characteristics of S4? What is it a sign of?
Low-freq late diastolic sound (presystolic) after the onset of P wave on ECG (coinciding w/ activate phase of ventricular filling) -> intensify during expiration
It's a sign of diastolic dysfx (might see assc. degenerative mitral annular and aortic valve calcifications if this is due to systemic HTN)
What do you have to suspect w/ erythematous cutaneous marks in fern-leaf pattern + 2nd degree burn? What's the most common causes of death?
Lichtenberg fingers = erythematous cutaneous marks in fern-leaf pattern
This is lightning injury
Die from arrhythmias and resp failure
What do you have to suspect when you see calcium oxalate crystals (folded envelope) in urine + ballooning and vacuolar degeneration of PCT?
Ethylene glycol poisoning
What is hepatorenal syndrome and what do you find in kidney?
Advanced liver disease w/ portal HTN leading to development of renal failure
Hallmark is renal vasoconstriction
Where does blunt aortic injury (like from car crash) usually happen?
At the aortic isthmus that's tethered by ligamentum arteriosum -> fixed and immobile compared to adj aorta
See widened mediastinum
What do you find on auscultation in nonstenotic bicuspid aortic valve?
Aortic ejection sound -> early systolic, high-freq click head over apex and/or right second interspace
What can saddle nose be a consequence of?
Nasal ulceration -> so if this happens + oliguria, suspect Wegener
What kind of cardiomyopathy is assc. w/ peripartum and chronic supraventricular tachycardias? Wet beri beri?
All dilated cardiomyopathy
What do you neeed to do before dx dilated cardiomyopathy?
Rule out pericardial disease, valvular defects, CAD, cardiac rhythm disturbances -> dilated cardiomyopathy is a dx of exclusion
Dx w/ membranous glomerulopathy and now have varicocele. What happened?
Loss of antithrombin III in urine (nephrotic syndrome)
Varicocele is most likely b/c occlusion of renal vein (usually either by tumor or thrombus, in this case it would be thrombus)
Don't assc. varicocele w/ edema, assc. it w/ thromboembolic state
See Maltese cross under polarized light on urine sample. What's the assc.?
Maltese cross -> oval fat bodies from lipid loss in urine -> assc. this w/ nephrotic syndrome (liver increases synthesis of lipoproteins and this is lost in urine)
Diff in ages and how rheumatic mitral valve disease present?
First few decades of life: MR
Older: mixed (MS and MR)
What are abd and flank bruits present during both systole and diastole specific for?
Renal artery stenosis
DD of renal artery stenosis in young and old pts?
Young women of childbearing age: fibromuscular dysplasia
Old pts: atheroslerosis
What are the macro and microscopic findings of renal artery stenosis?
Macro: one kidney is smaller than the other -> under LM will see tubular atrophy w/ decreased epithelial size, tubulosclerosis, patchy inflammation, fibrosis of interstitium, and glomerular atrophy
What should you assc. NBTE (non-bacterial thrombotic endocarditis) caused by hypercoagulability w/?
Cancer ("marantic/marasmic endocarditis") -> strong assc. of NBTE w/ mucinous adenocarcinomas of pancreas and adenocarcinomas of the lungs
Pathogenesis is the same as Trousseau syndrome (tumor-assc. release of procoagulants)
Diff bet. Janeway lesions and Osler nodes?
Janeway: palms and soles, painless, from septic embolization
Osler nodes: pulps of fingers and toes, painful
What paces the ventricles in 3rd degree heart block?
AV nodal cells (SA paces atrial contraction independently)
HR of SA conduction? AV? Purkinje and His bundle?
SA: 60-100 bpm
Purkinje and His bundle: 20
What can membranous glomerulopathy be secondary to?
Systemic: DM, tumors, SLE
Drugs: gold, penicillamine, NSAIDs
Infections: HBV, HCV, malaria, syphilis
What do you have to worry about w/ the initial dose of ACEi?
First-dose hypotension -> so consider predisposing factors like hyponatremia, hypovolemia (DIURETIC USE), low BP, high renin and aldos, renal impairment, and HF
How do you tell DI and primary polydipsia apart from labs?
DI: plasma Na+ conc > 142 mEq/L (water loss)
Primary polydipsia: conc will also see increase in urine osmolality during water deprivation study and little response to vasopressin administration
Tx of nephrogenic DI?
HCTZ (paradoxic antidiuretic effect)
Indomethacin (prostaglandins inhibit ADH)
Most common site of atherosclerotic plaques?
Abd aorta > coronary arteries > popliteal > int. carotids > circle of Willis
What defect is usually assc. w/ persistent truncus arteriosus?
What drugs can cause renal tubular OBSTRUCTION?
Sulfonamides, methotrexate, acyclovir, and triamterene
Most common drug causing interstitial nephritis?
How does kidney correct metabolic acidosis? (besides increasing HCO3- reabsorption)
Increased secretion of H+, NH4+, and H2PO4- -> so get decreased urinary pH
How do you treat symptomatic UTIs?
3-day course of fluoroquinolone or TMP-SMX
What do you see under microscope in myxomatous changes of arteries? What is the assc.?
Basket weave pattern of separated elastic fibers
Clef-like spaces filled w/ amorphous extracellular matrix separate elastic and fibromuscular components of tunica media
Assc. w/ aortic aneurysms (NOT berry aneuryms)
What is a false aneurysm?
Blood leaks thru layers of blood vessel or heart and forms hematoma outside wall
Seen in leaks at anastomosis site and postinfarction myocardial ruptures that's contained by pericardial adhesions
How do you grossly dx pulsus paradoxus?
Palpate radial pulse and noting that it disappears during inspiration
What is pulsus alternans?
Beat to beat variation in magnitude of pulse pressure (in the presence of regular cardiac rhythm) -> occurs in LV dysfx
What is dicrotic pulse?
Pulse w/ 2 distinct peaks (palpate in carotid arteries), one during systole and another during diastole -> seen in severe systolic dysfx
What is hyperkinetic pulse?
Rapid ejection of large SV against decreased afterload -> seen in fever, exercise, high-output conditions (PDA, AV fistula)
What happens to GFR after single nephrectomy?
Reduced to 50% immediately after surgery
Go back up to 80% w/in 6 weeks post-op
A probe at cardiac apex maps out blood flow across mitral valve (y) vs. time. You see 2 positive peaks, one tall and one short. What are they?
Tall positive peak: S3 (blood rushes in during rapid filling of ventricles in mid-diastole)
Short positive peak: atrial contraction
S3 vs. S4?
S3: rapid mid-diastolic FILLING & splashing of ventricles that aren't compliant -> like restrictive CM, dilated CM, children, pregnant women, HF (either diastolic or systolic, from increased end-SYSTOLIC volume and pressure)
S4: forceful atrial CONTRACTION pushing blood into stiffened ventricles (ventricular hypertrophy in HTN)
Antiarrhythmics that can cause changes in lungs?
Anything w/ the lungs, just pick amiodarone
But remember that procainamide is assc. w/ SLE-like syndrome that can involve delay-onset pleuritis too
Pt presenting w/ hypotension and sepsis later has a rise in serum creatinine. What's happening to kidney?
ATN! -> so focal necrosis of tubular epithelium in medulla will be seen (glomeruli normal!) -> might see tubule lumen occluded w/ casts but this is not the cause of illness (medullary ischemia is)
Extrinsic and intrinsic toxins that can cause ATN?
Extrinsic: aminoglycosides, amphotericin B, contrast dye, heavy metals, etc
Intrinsic: myoglobinuria, hyperuricemia, Bence Jones proteins (MM)
What synthesis in increased in cardiac hypertropy?
NOT collagen -> that's assc. w/ fibrosis
NOT mitotic activity -> cardiac cells don't divide
Long term anticoagulant of choice after putting in mechanical heart valves?
Warfarin (heparin until warfarin takes effects)
Can be combined w/ aspirin (but aspirin can't replace warfarin)
HIV-positive male w/ facial puffiness + renal epithelial enlargement and vacuolization + glomerular capillary wall collapse + tubules show cystic dilatation filled w/ proteinaceous materials. Dx?
Focal segmental glomerulosclerosis, collapsing variant
What' value is considered high anion gap?
> 10-14 mEq/L
Decreasing what would increase myocardial contraction velocity?
Decreases afterload -> increases myocardial contraction velocity (max when afterload is 0)
Increasing preload will increase contraction velocity only to a point (then velocity starts going down after that)
"Systolic murmur heard along left sternal border that intensifies upon standing"?
ECG sign for hyperkalemia? Hypokalemia?
Remember that K+ is assc. w/ repolarization phase
So too much K+ will cause peaked T wave (repolarization wave) -> earliest sign
Too little K+ will cause ST depression
ECG sign for hypercalcemia? Hypocalcemia?
Remember that Ca2+ is assc. w/ ventricular contraction -> so this is represented on ECG as QT interval
So too much Ca2+ will cause shortened QT interval
Too little Ca2+ will cause prolonged QT interval
What happens to pulse pressure w/ infusion w/ a-agonist? B-agonist? Epinephrine?
Pulse pressure is systolic BP - diastolic BP
A-agonist (phenylephrine): decreases pulse pressure (it increases systolic BP, but it also reflexively decreases SV and increases afterload -> so this means diastolic BP will go up as well)
B-agonist (isoproterenol): increases pulse pressure (it decreases PVR and diastolic BP)
Epinephrine: increases pulse pressure
Mechanism of cough syncope? Micturition syncope?
Cough syncope (usually in COPD pts): coughing causes rise in intrathoracic pressure -> decreased venous return to heart -> decreased CO and decreased cerebral blood flow -> so same mechaism as valsalva
NOT vetebrobasillar deficiency, which is a bigger problem that would present w/ numerous serious signs
Micturition syncope: rising at night to pee causes orthostatic hypotension from venous pooling
What do you need to think about in new, unexplained edema in lower extremities when obv causes are not present (no HF, liver cirrhosis, nephrotic syndrome)?
IVC obstruction (probably by renal cancer esp if can palpate flank mass) -> so get bilateral leg edema w/ distended lower abd veins and faint systolic bruit
End-diastolic volume and end-systolic volume in diastolic dysfx vs. systolic dysfx?
Systolic dysfx (dilated): increased end-diastolic and end-systolic volumes -> this happens in global ischemia too
Diastolic dysfx (thickened): decrease in both
What happens to HR, end-systolic volume, and end-diastolic volume in pericardial constriction?
End-diastolic volume: decreased (restricted ability to expand)
End-systolic volume: also decreased
HR: increased (heart tries to maintain CO in the setting of decreased preload)
Pt smokes and has DM and HTN. Doing what would reduce the risk of ischemic heart disease the most?
Stop smoking (b/c smoking promotes BOTH atherosclerosis and platelet aggregation)
How do you differentiate bet. water diuresis vs. osmotic diuresis?
Water diuresis: urine osmolality think DI, primary polydipsia
Osmtic diuresis: urine osmolalit > serum osmolality -> think DM
4 causes of nephrogenic DI?
Drugs: lithium, amphotericin B, gentamycin, cisplatin
Hypercalcemia: b/c lots of Ca2+ downregulates aquaporins in collecting tubules -> dehydration -> so think about nephrogenic DI w/ SCC of lungs producing PHrP
What's a compound in cigarette that's assc. w/ bladder cancer?
Also found in leather, textile, etc
Where along nephron would sodium resorption be most affected w/ mitochondrial inhibitor?
All segments use basolateral Na/K+ ATPase, but PCT is the segment that reabsorbs most amount of Na+ (65-80%)
Renal tubular defects?
"FABulous Glittering Liquid"
PCT: FAnconi syndrome (lose AAs, glucose, HCO3-. PO43-) -> RTAII
Thick asc. limb of loop of Henle: Bartter (like using loop diuretics)
DCT: Gitelman (like using thiazide diuretics)
Collecting tubules: Liddle (AD, presents like aldos overload but w/ low aldos)
Wilms tumor, Aniridia (no iris), Genitourinary malformation, Retardation
Cancer assc. w/ Beckwith-Wiedemann syndrome?
Beckwith-Wiedemann: large everything (head, tongue, organs) + omphalocele + umbilical hernia