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Flashcards in Cardio - Stuff Missed Deck (157):
1

How do ACE inhibitors cause renal failure?

ACE inhibitors dilate efferent tubules, thus decreasing GFR and renal perfusion.

- For patients who depend on efferent arteriole constriction to maintain renal perfusion (pts with renal artery stenosi), ACE inhibitors can cause ARF

2

Discuss ACE inhibitors and aldosterone

block release of aldosterone resulting in decreased Na reabsoprtion and increase K retention in distal and collecting tubules

- responsible for hyperkalemia often seen with ACE inhibitor therapy

3

Cyclooxygenase 2 (COX-2)

- molecular weight of 72kd
- inducible enzyme that is normally undetectable in most tissue except in case of inflammation

4

"Coffee ground emeisis"

suggests upper GI bleed
- coffee ground color caused by oxidation of heme
- patients may lose a lot of blood and may experence hypvolemic shock

5

Hypovolemic shock

- when patient loses > 10% of blood volume
- sympathetic NS constricts arteriole and venous beds and stimulate heart
- arteriole constriction - increases total peripheral resistance and maintain organ pressure
- venous constriction - increases blood return to heart to maintain preload

6

Discuss IV fluid infusions and preload

IV infusions increase intravascular volume by varying degrees of solute composistion
- Preload increase increases mycocardial sarcomere lendgth and increases stroke volume and cardiac outpute

7

Most common cause of mitral stenosis

Rheumatic dever

8

Infective endocarditis

- results in larger, more friable vegetations
- destruction of valve leaflet, may cause regurgitation
- embolization of vegetations can cause stroke or septic infarct resulting in brain abscess

9

Degenerative calcific deposits

develop in mitral valve annulus in women > 60
- found in ppl with myxomatous, floppy mitral valve or elevated left ventricular pressure

10

Fibrinous pericarditis

- result of prolonged rheumatoid arthritis
- rarely involve the endocardium or heart valves

11

Reperfusion injury

- when after blood flow is returned to ischemic tissue, cells within damaged tissue die
secondary to:
- oxygen free radial generation
- mitochondrial damage
- inflammation

12

Mechanisms of reperfusion injury

1. Oxygen free radical generation by parenchymal cells
2. Severe, irreversible mitochondrial damage described as " mitochondrial permeability transition"
3. Inflammation - attracts circulating neutrophils that cause additional injury
4. Activation of complement pathway, causing cell injury and further inflammation

13

Explanation of rise in serum creatinine kinase after thrombus extraction

- Result of reperfusion injury
- When heart, brain, or skeletal muscle are injured, enzyme creatinine kinase leaks across cell membrane and into circulation

14

Risk factors for intimal tears leading to aortic dissections

- Hypertension

15

Smoking (risk factor for which vascular diseases)

1. ATHEROSCLEROSIS --> aortic aneurysm

2. BUERGER'S DISEASE (Thormboangitis obliterans)

16

If LAD is occluded by atherosclerotic plauque, what is the preferred vein for grafting?

Left internal mammary artery - preferred vseel

17

If mutiple coronary arteries/vessels are occluded, what is the preferred vein for grafting?

Great saphenous vein - longest vein in body

18

Great saphenous vein

- superficial vein that originate on medial side of foot, courses anterior to medial malleolus, and then travels up medial aspect of leg thigh
- drains into femoral vein within femoral triangle, inferior lateral to pubercle triangle

19

How soon after ischemia do the cardiomyocytes lose contractility?

60 seconds after ischemia

- due to cessation aerobic glycolysis
- ATP decreases rapidly due to high myocardial demand

20

Myocardial studding

if ischemia lasts less than 30 minues
- restoration of blood leads to REVERSIBLE contractile dysfunction
- contractility returns to normal within days or hours

21

What happens to cardiomyocytes after more than 30 minutes of ischemia?

IRREVERSIBLE injury

22

Most reliable indicator of the severity of mitral stenosis

S2 to opening snap interval (A2-OS interval)

- the shorter the interval, the more severe the stenosis
-

23

Xanthelasmas

- yellowish macules/papules found on medial eyelids
- dermal accumulations of cholesterol and triglucerides
- associated with primary and secondary hyperlipidema or dyslipidemia
- LDL receptor abnormality is most common cause

24

Normal variant cardiac anomaly in adult patients?

Patent foramen ovale (present in 20 - 30% adults
- remains functionally closed, but in situations of increased right atrial pressure may cause right atrial shunt

25

Endocardial cushion defect

- failure of complete fusion of endocardial cushions in atrioventricular canal
- leads to perisistent AV canal
- associated with Down Syndrome

26

Persistent truncus arteriosus

- results form incomplete embryonic development of aorticopulmonary septum resulting in single great vesel from heart
- Aorta, Pulm Artery, and coronary vessels
- causes cyanosis and if uncorrected, death within first year of life

27

Ductus arteriosus

closes by 3rd month of life in response to high PaO2 of blood shunting from left to right through the ductus after birth

- patency beyond 1 year is abnormal

28

Sotalol

both adrenergic blocking properities
class 3 anti-arrhythmic (K+ channel blocking) properties
- prolongs both the PR interval and QT interval

29

STEMI and subsequent Q-wave formation is the result of ...

Fully obstructive thrombrus superimposed on ruptured atherosclerotic coronary artery plaqye

30

Q-wave in V1 - V4 leads. Where is infarct?

Anterior wall (LAD)

31

Q wave in V1 - V2 leads. Where is infarct?

Anteroseptal (LAD)

32

Q wave in V4 - V6 leads. Where is infarct?

Anterolateral (LCX)

33

Q wave in I, AVL leads. Where is infarct?

Lateral wall (LCX)

34

Q wave in II, III, aVL leads. Where is infarct?

Inferior wall (RCA)

35

Unstable angina. Describe vasculature.

Caused by obstruction of at least 75% of coronary artery lumen.

36

Prinzmetal's angina

- caused by vasospasm
- may occur at sites of coronary atherosclerosis and result in transmural ischemia

37

Atherosclerotic plaques develop predominantly in which arteries?

- Large elastic arteries (e.g. aorta, carotid, illiac)
- Large/medium sized muscular arteries (e.g. coronary and popliteal arteies)

38

Order of vessels in which atherosclerotic plaque form.

Abdominal aorta > Coronary arteries > Popliteal arteries > Internal carotid > Circle of Willis

39

Aortic rupture

- commonly caused by motor vehicle accident
- aortic isthmus (connection between ascending and descending arteries distal to where left subclavian branches off of aorta)

40

Peak intensity of aortic regurgitation murmur

- occurs after closure of incompetent aortic valve, when the pressure gradient and the left ventricle are at mazium

41

Aortic Regurgiation murmur

heard best on left sternal border when patient leans forward (bringing valve close to the chest wall) and at end of expiration

42

Hypetrophic cardiomyopathy

- most common cause of ventricular fibrillation in patients < 30
- most common cause of sudden cardiac death in young athlete

43

Restrictive cardiomyopathy

- associated with endomyocardial fibriosos, endocardial fibroelastosis, idiopathyic myocardial fibrosis

44

Stab wound in fourth intercostal space in the midclavicular line hits what structures?

Primarily left lung then if deep enough left ventricle

45

Stab wound in fourth intercostal space in left sternal border hits what structures?

Primarily right ventricle.

46

Collagen I

Dermis, bone, tendons, ligaments, dentin, cornea, blood vessels & scar tissue

47

Dysfunction of collagen I

Osteogenesis imperfecta

48

Collagen II

cartilage, vitreous humor & nucleus pulposus

49

Collagen III

Skin, lungs, intestines, blood vessels, bone marrow, lymphatics & granulation tissue

50

Associated with collagen III

Ehlers-Danlos syndrome

51

Collagen IV

Basement membrane

52

Associated with collagen IV

Alport syndrome

53

Alpha 1 receptors

- Increase IP3
- Peripheral vasoconstriction
- Mydriasis (contraction of pupilary dilator muscle)
- Intestinal and bladder sphincter muscle contraction

54

Alpha 2 receptors

- DECREASE cAMP
- decrease release of NE and insulin
- decrease lipolysis
- increase platelet aggregation

55

Beta 1 receptors

- INCREASE cAMP
- increased heart contractility and HR
- increased lipolysis
- increased renin release

56

Beta 2 receptors

- INCREASE cAMP
- vasodilation
- bronchodilation
- increased HR and contractility
- increased insulin production and aqueous humor production
- decreased uterine tone
-

57

Norepinpherine

stimulates cardiac B1 receptors which utilize cAMP pathways

58

Side effect of anthracycline chemo agents (doxirubicin, daunorubicin, epirubicin, idarubicin) on heart

Dilated cardiomyopathy

- these agents form free radical in myocardium
- often presents with symptoms of left and right CHF

59

Method to prevent dilated cardiomyopathy after doxorubicin administration

Dexrazoxane - iron chelating agent decreases formation of oxygen free radicals

60

Causes of restrictive cardiomyopathy

- associated with hemochromatosis
- amyloidosis
- sarcoidosis
- radiation therapy

61

Hypertrophic cardiomyopathy

- associated with mutation of B-myosin heavy chain

62

Pericardial fibrosis

cardiac surgery
radiation therapy
viral infections

63

Torsades de pointes

ventricular tachycardia with shifting sinusoidal waves on ECG
- can progress to ventricular fib
- anything that prolongs QT interval can lead to T de P

Tx: magnesium sulfate

64

Treatment of Torsades de Pointes

Magnesium sulfate

65

Jervell and Lange-Nielsen syndrome

congenital long QT syndromes due to defects in cardiac sodium and potassium channels
- can present with severe congenital sensorineural defects

66

Wolf-Parkinson White syndrome

ventricular pre-exciation ndrome
due to accessory conduction pathway from atria to ventricle that bypasses AV node
- ventricles depolarize earlier - leading to DELTA wave

67

Treatment of Wolf-Parkinson White Syndrome

Procainaomide, Amiodarone

68

Atrial fibrillation

chaotic and erratic baseline (irregularly irregular) with NO DISCRETE P WAVES in between irregular spaced QRS complexes

- can result in atrial stasis and lead to stroke

69

Treatment of atrial fibrilliaotn

rate control, anticoagulation, and possible cardioversion

70

Atrial flutter

rapid succession of identical, back to back atrial depolarization waves
- "sawtooth appearance)


71

Treatment of atrial flutter

Rx conversion to sinus rhythm: Class IA, IC, or III antiarrhythmics

Rate control: B-blocker or Ca channel blocker

72

Ventricular fibrillation

completely erratic rhythm with no identifiable waves.
Fatal arrhythmia without immediate CPR and defibrillation

73

1st degree AV block

PR interval is prolonged (> 200 msec)
- Assymptomatic

74

2nd degree AV block: Mobitz type I

Progressive lengthening of PR interval until a beat is dropped (P wave is not followed by QRS complex)

- Usually assymptomatic

75

2nd degree AV block: Mobitz type II

- dropped beats that are not preceded by change in length of PR interval
- Abrupt nonconducted P waves result in pathological condition
- Often found as 2:1 block, where there are 2 or more P waves to 1 QRS complex
- May progress to 3rd degree heart block
- Treated with pacemaker

76

3rd degree AV block (complete)

- Atria and ventricles beat independently of each other.
- Both P waves and QRS complexes are present, though P waves have no relation to each other
- Atrial rate are faster than ventricular rate
- Usually treated with pacemaker
- Lyme disease can result in 3rd degree AV block

77

ANP

released from atrial myocytes in response to increased blood volume and atrial pressure
- causes vascular relaxation and decreased NA reabsorption at collecting tubules
- constricts EFFERENT renal arterioles and relaxes AFFERENT renal arterioles (cGMP mediated)
- promotes diuresis and " escape form aldosterone"

78

Metabolites mediating vasodilation in heart

CO2, adenosine, NO

79

Metabolites mediating vasodilation in brain

CO2

80

Pulmonary hypertension

manifests with dyspnea on exertion and can progress to cor pulmonale with RV hypetrophy, leading to sudden cardiac death
-
- taking appetite suppressants for > 3 months can lead to Pulmonary HTN

81

Cerebral berry aneurysms

associated with AKPD and Ehlers Danlos syndrome
- risk factors are hypertension and smoking

82

Medial calcinosis

calcific deposits in muscular arteries in ppl > 50 y.o
- femoral, tibial, radial, and ulnar arteries are typically affected
- visible by radiography and palpable
- assymptomatic and DO NOT NARROW vessel lumen

83

Aortic dilation

result of HTN, aging, and/or aortic stenosis
- can result from atherosclerosis,, cystic medial degeneration, aortitis

84

Left atrial enlargement

can cause left recurrent laryngeal impingement
- can result in dysphagia
- can result in left vocal cord paresis and hoarseness

85

Ortner syndrome

mitral stenosis that leads to left atrial enlargement that result in impingement on left recurrent nerve

86

Drug efficacy

maximum pharmacodynamic effect achievable by drug

87

Potency

refers to dose of drug required to produce given effect.

Drugs that bind to receptors will higher affinity or better able to gain access to target tissue will have greater portency (lower ED50)

88

Most common causes of lightening related death

Fatal cardiac arrhythmias and respiratory failure

89

Lichtenberg figures

cutaneous red marks in fern-leaf pattern
- seen with lightening injury

90

Claudication

- intermittent muscle pani caused by exercise and relieved by brief period of rest
- result of atherosclerosis of larger arteries
- stenotic atheromas (lipid filled intimal plaques)

91

Hyaline arteriosclerosis

homogenous deposition of hyaline material in initima and media of small arteries and arterioles

92

Hyperplastic arteriosclerosis

results from malignant hypertension
- seen in diastolic pressures > 120 mm Hg
- leads to onion-like concentric thickening of arteriolar walls due to SMC

93

Valsava maneuver in auscultation

decreases venous return reduce left ventricular volume and blood pressure
- MS and MVP become MORE audible
- Aortic stenosis becomes less audible

94

S3

low frequency sound
results from left systolic failure - chamer remains dilated
- listen best on left lateral ducubitus position

95

Signs of irreversible injury in heart

Appearance of vacuoles and phospholipids densities in mitochondria
- implies permanent inability to generate ATP

96

Progressive exertional dyspnea in heavy smoker

Think: COPD!

97

Dilation of RV and increased central venous pressure

Right heart failure
- interstitial fluid pressure rises due to increae in net plasma filtration
- as interstitial fluid pressure increases, lymphatic drainage does to prevent intestitial edema
- Edema occurs when lymphatics can't compensate

98

Sudden cardiac death

cardiac arrest that begins within 1 hours od event and proves fatal
- mostly due to coronary artery disease
- acute plaque change leads to acute MI which leads to letal arrythmias

99

Most common cause od death in MI patients

Cardiac arrhythmias

100

Phase 0 of cardiomyocytes vs. Phase 0 of Purkinje cells

Phase 0 of cardiomyocytes (pacemaker cells) have Ca influx

Phase 0 of Purkinje cells is due to influx of Na

101

Turner's Syndrome

Triad: "streak ovaries, amenorrhea, and infertility
- most associated with coarctation of aorta, webbed neck, low posterior hairline, and short stature

102

Kawasaki's disease

vasculitis of medium sized arteries that presents with persistent fever, bilateral conjunctivitis, cervical lymphadenopathy and mucocutaneous involvemet

-

103

Most common cause of dilated coronary arteries

Elevated right-sided heart pressure (anything that cause right atrial dilation) secondary to pulmonary artery hypertension

** coronary arteries not seen on ECG in healthy inviduals

104

Normal splitting

inspiration leads to drop in intrathoracic pressure and increase in venous return.
- more blood in RV and longer ejection time
- DELAYED CLOSURE OF PULMONIC VALVE

105

Wide splitting

- Seen in conditions that delay RV emptying (e.g. pulmonic stensois, right bundle blokc0

- Delay in RV emptying causes delayed pulmonic sound (REGARDLESS OF BREATH_

106

Fixed splitting

Seen in ASD. ASD --> left to right shunt --> RA and RV volumes --> increased flow through pulmonic valve such that regardless of breath, pulmonic valve is GREATLY delayed

107

Paradoxical splitting

seen in conditions that delay LV emptying (aortic stenosis, left bundle branch block)

- Normal order of valve closure is reversed (pulmonic valve closes before aortic balbe)
- on inspiration, P2 cloes later and moves closer to AP

108

Congenital heart defects associated with Down's syndrome

endocardial cushion defects

109

Common genetic cause of Down syndrome

- caused by maternal meiotic nondisjunction

110

Fenoldopam

D1 receptor agonist
- causes arteriolar dilation and natiuresis leading to decreased SVR and BP reduction
- only IV agent that improves renal perfusion

111

Esmolol

short acting B-blocker
- decreases heart rate, contractility, and cardiac output
- used in post operative hypertension

112

Nicardipine

Ca channel blocker that works by blocking Ca in vascular smooth mucle

113

Signs of acute pericarditis

- sharp and pleuritic pain
- decreases when patient sits up and leand forward
- canbe caused by myocardial infarction, rheumatic fever, or uremia or infection
- Pericardial friction rub is most striking sign

114

Kussmaul's sign

paradoxical increase in JVP during inspiration
- found in chronic constrictive pericarditis, severe RHF, tricuspid stenoisis and RARELY cardiac tamponade

115

Pulsus paradoxus

drop in systolic blood pressure of > 10 mm Hg or more during inspiration
- exaggeration of response during inspiration

116

Prostacyclin

produced by vacular endothelial cell
- when secreted vasodilates
- inhibits platelet aggregation
- increases vascular permeability
- opposes THROMBOXANE

117

Hageman Factor

synthesized by liver and is activated by collagen exposed to damaged vascular Basement Membrane

118

Kallikrein

converts kininogen to bradykinin. Bradykinin is normally degraded by ACE and is responsible for cough seen in bradykinin

119

Unilateral renal stenosis

cause of secondary hyperension
- caused by atheromatous plaque in renal artery
- occurs more in patients in males and increases with age
- ischemic kidney secretes high levels of renin to cause HTN
- ischemic kidney atrophies

120

Irregularly irregular tachyarrhythmias

Atrial fibrillation (absent P waves)

121

Torsades de Pointes

- heart beat is fast, but rhythm is regular

122

Dofetillide

Class 3 antiarrhythmic agen blocks potassium efflux
- prolongs phase 3 of myocyte action potential

123

Potassium-sparing diuretics act where?

In collecting tubule

124

Acetazolamide

- blocks carbonic anhydrase thus block reabsorption of HCO3
- works in proximal tubules

125

Micro changes after MI: 0-4 hrs

minimal change (normal)

126

Micro changes after MI: 4 -12 hrs

early coagulation necrosis, edema, hemorrhage
WAVY FIBERS

127

Micro changes after MI: 12 -24 hrs

coagulation necrosis and marginal contraction band

128

Miro changes after MI: 1 - 5 days

coagulation necrosis and neutrophilic infiltrate

129

Micro changes after MI: 5 - 10 days

macrophage phagocytosis of dead cells
- greatest risk of ventricular rupture

130

Micro changes after MI: 10 to 14 days

granulation tissue and neovascularization

131

Micro changes after MI: 2 weeks to 2 months

Collagen deposition/Scar formation

132

Most common cause of aortic stenosis

caused by bicuspid aortic valve

133

AV shunts

- can be congenital or acquied
- can increase preload and decrease afterload by routing blood directlt from arerioal system
- result in high output cardiac failure

134

Temporal (Giant cell) arteritis

characterized granulomatous inflammation of media
- most common form of vasculitis
- usually elderly woman complaining of headaches and risk of blindness
- responds well to glucocorticoid therapy

135

Drugs used for MRSA infections

- Vancomycin
- Daptomycin
- Linezolid

136

Vancomycin

- blocks glycopeptide polymerization by binding to tightly to D-alanyl-D-alanine

Side effects: Red man syndrome (mediated by histamine); Nephrotoxicity

137

Daptomycin

- depolarization of cell membrane

Side effects: myopathy and CPK elevation; inactivated by pulmonary surfactant

138

Linezolid

inhibits bacterial protein synthesis by binding to 50 S unit

- Side effects: cause thrombocytopenia, optic neuritis, high risk for serotonin syndrome

139

Specific sign of left sided heart failure

Orthopnea

140

Specific sign of RHF

Bilateral lower extremity edema and congestive hepatomegaly

141

Myocardial hibernation

- repetitive ischemia of cardiomycoctes or persistent hypoperfusion of mycocytes that result in loss of fxn
- can be reversed with reperfusion

142

Intensity of AS murmur is determined by abnormal pressure gradient between LV and Aorta during systole

True

143

Paroxysmal supraventricular tachycardia

- occurs in young people without real heart hx
- sudden onset of palpitations and may resolve spontaneously

144

Adenosine

- used to treat paroxysmal supraventricular tachycardia
- rapidly cleared and half-life of 10 secons
- commonly causes flushing, bronchospasms (chest burning), and high grade block
- used for chemical stress test

145

Verapamil

Class IV antiarrhythmic
- most cardioselective of all Ca channel blcoker
- assocciated with constipation and gingerval hyperplasia

146

Amiodarone

Class III antiarrhythmic and overdose or toxicity with lidocaine most commonly causes neurologic symptoms

147

Pathogenesis of atherosclerotic plaques

release of PDGF by locally adherent platelets, endothelial cells, and macrophages, promotes migrations of SMCs from media into intimas

148

Phenoxybenzamine

non-selective irreversible a1 and a2 adrenergic antagonist that reduces number of receptors available

149

Aschoff bodies

myocardial granulomas
- associated with rheumatic carditis
- contain plump macrophages with abundant cytoplasm and central round to ovoid nuclei with central ribbons of chromatin (Anitschow cells)

150

Hypertrophic cardiomyopathy

due to abnormal systolic anterior motion of anterior leaflet of MV toward hypertrophied interventricular septum

151

Strep viridans

- produce dextrans from glucose that aid organisms colonize dental enamel and heart surfaces
- can cause subacute bacterial endocarditis in patients with already existing cardial defects after dental manipulation

152

Fibrous initimal thickening with endocardial plaques limited to right heart

Carcinoid syndrome
- endocardial fibrosis due to serotonin levels and 5-hydroxyindoleacteic acid

153

Carcinoid syndrome symptoms

episodes of skin flushing, abdominal cramping, vomiting, and diarrhea

- severity of symptoms correlates with serotinin levels and urinary excretion of serotinin metabolite, 5-HYDROXYINDOLEACETIC ACID

154

Adult (post-ductal ) type of congenital aortic coarctation

- signs of hypertension in arterial tree proximal to coractation
- hypoperfusion in lower extremities
- results in dilated intercostal artries

155

Post-ductal congenital aortic coarctation

Triad:
- upper body hypertension (headaches, dizziness)
- Diminished lower extremity pulses (difficulity walking)
- Enlarged intercostal artery collaterals

156

Nitrates + Phosphodiesterase (PDE) inhibitors used for erectile dysfunction and pulmonary hypertension

- causes PROFOUND systemic hypotension
- both classes of drugs (nitrates + PDE inhibitors) increase cGMP - which causes smooth muscle dilation

157

Wolf-Parkinson White Syndrome triad

- SHORTENED PR- interval
- DELTA wave at start of QRS complex
- widened QRS interval

** pre-exciation syndrome associated with re-entry circuit
- associated with PSVT