UWorld Cardiology Flashcards
(139 cards)
“Please pray for me” in Emergent setting. Against your beliefs. What do you do?
Say “you are in my thoughts” Answer was NOT call a chaplain. Shifting responsibility is usu not correct in USMLE
MAP INC how much during exercise? What is this due to?
Usu only 20-40 mmHg. THis is due to massive vasodilation to muscles (can get up to 85% of bodies blood!)Constriction of venous INC blood flow return to the heart.
Most common endocarditis w/ dental work?
Strep Viridans/mutans
Culture Negative Endocarditis?
Bartonella, Coxiella, Mycoplasma, Histoplasma, Chlamydia, HACEK (Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella)
When would you see enlarged intercostal arteries in young child?
Turners - Co-arctation - leads to poor flow to the
Familial Hypercholesterolemia inheritance pattern?>
AD
Knife wounnd to left sternal border, 4th intercostal space. Hits?
Right Ventricle. RV is majority of anterior surface of the heart.
Type 1 ErrorType 2 ErrorPower?
T1 Error - False Positive (seeing a different when there is no difference in reality)T2 Error - False Negative (seeing no different when there is a difference)Young scientist commit T1 error as they are trying to promote their career. Old scientist commit T2 error because they are stuck in their own ways. However, Old scientists have the power. Power = 1-T2 Error
Endocardial cushin defects lead to ?
Defects in AV septum - initially acyanotic, may form Left to right shunts that reverse due to pulmonary HTN (Eisenmernger syndrome) -> cyanotic
If they say, cyanotic since birth.. what do you think?
TranspositionTricuspid Atresia TetralogyTotal AnomalousTruncus ArteriosusEndocardial cushin defects (ASD, VSD) would not be cyanotic since birth
What are Tetralogy, Transposition, and Truncus Arteriosus due to?
Abnormal migration of neural crest cells through pirmitive truncus arteriosus and bulbus cordis
Mech of Doxorubicin, toxicity?
Formation of free radicals -> dialted CM. Dose dependant. Can get swelling of sarcoplasmic reticulum (early sign of txo) -> loss of myocytes (myofibrillar dropout) .Prevent doxorubicin CM w/ dexrazoxane (Iron chelating agent) that DEC oxygen free radicals.
Most reliable auscultatory indicator of severity of mitral stenosis? What indicates severity? What is clinical standard for diagnosis of MS?
A2/S2 to Opening snap time interval. Shorter the interval, MORE severe the stenosis. Think, the STENOSIS IS SO BAD, that the pressure INSTANTLY builds up and it HAS to snap openThe more thickened and fibrotic the MV, the earlier the tensing and snapping occurs. MS also assoc w/ INC mean transvalvular pressure on doppler.Therefore, the opening snap time is inversely related to transvalvular pressure.
Histology of acute cardiac rejection (2 weeks)Histo of chronic rejection?
Cell mediated - dense mononuclear lymphocytic infiltrates. (T lymphocytes sensitized against graft MHC antigens). Scant inflam cells and interstitial fibrosis
Acute hypersensitivty to cardiac transplant leads to?Compare to histo of hypersensitivity myocarditis?
Acute cessation of blood flow to organ due to preformed Ab. Perivascular infiltrate /w abundant Eos, often following new drug therapy -> atopipc response
Patchy necrosis w/ granulation tissue on heart?
Think ischemic damage. Atherosclerosis of MI
Hemolysis pattern of Group D strep. DifferentiateEnterococci, E. faeciumNonenterococci S. bovisAssoc for either one? When you see them?
Gamma - no hemolysis of GDS.Enterococci, E faecium - grow in bile AND 6.5% NaGenitourinarny procedures (cystoscopy etc)Nonenterococci, S. bovis - grow in bile, NOT NaClColonic malignancies
Strep viridans/mutans - when do you get cardiac complications?
After dental work/dental caries
MAIN THERAPEUTIC EFFECT OF sublingual NITRATES (nitroglycerin)m IN DEC CHEST PAIN?
DEC in LV volume (DEC preload, buy promoting venodilation)have modest dilatory effect on cornoary arterioles and moest DEC in afterload through arteriolar vasodilation.
Formulas for.Volume DistributionHalf lifeLoading DoseMaintenance Dose
Volume Distribution = Dose/[Plasma]Half life = .7(VD)/CLLoading Dose = (VD)[PlasmaSS]\FMaintenance Dose = PlasmaSS(t)/F
How does AV shunt affect preload and afternload?
INC preload and DEC afterload. INC preload (as venous blood, big reservoir returns), and DEC afterload (because pressure is decreased w/ bypass into venous system.High volume AV shunts can lead to high output cardiac failure.
Why are skeletal muscles resistant to calcium channel blockers - compared to cadriac and smooth muscle?
Skeletal does NOT rely on extracellular Ca. Cardiac, smooth muscles do rely on extracellular Ca entering via voltage gated L type Ca channels. Skeletal muscle does have RyR1 - L type channel coupling in T tubule system - BUT does not require extracellular Ca. Ca from SR binds to troponin C.Cardiac muscle has T tubule but does not have L-RyR coupling. In this case you have L type Ca channels in plasma membrane that open and allow influx of extracellular Ca - this Ca binds to sarcoplasmic RyR2 channel (Calcium induced calcium release) -> moves Ca out of sarcoplasmic reticulum. Smooth muscle - similar to cardiac (no extracellular), but Smooth muscle does NOT have troponin, it is calmodulin.
What is the major mediator of autoregulation between little change in blood flow over INC in mean arterial pressure?
NO. Most important mediated for coronary vascular dilation in large ateries and pre-=arteriolar vessels. Causes smooth muscle relaxation via cGMP second messasnger. Adenosine also acts as a vasodilatory element in small coronary arterioles
Where does adenosine do most of its work?
AV node - slows conduction and DEC automaticity by hyperpolarizing cells. Also vasodilatory in cornoary arterioles. DOC for abolishing SVT.