NBME CBSE Questions And Answers

Bulbus cordis correct answer: Smooth parts (outflow tract) of left and right ventricles endocardial cushions correct answer: Atrial septum, membranous interventricular septum; AV and semilunar valves neural crest left horn of the sinus venosus correct answer: coronary sinus posterior, sub cardinal, and supra cardinal veins correct answer: IVC Right common cardinal vein and right anterior cardinal vein correct answer: SVC Right horn of sinus venosus correct answer: Smooth part of right atrium (sinus venarum) Patent foramen ovale correct answer: failure of septum primum and septum secundum to fuse after birth Transposition of the great vessels Tetralogy of Fallot Persistent truncus arteriosus correct answer: Conotruncal abnormalities associated with failure of neural crest cells to migrate ductus venosus correct answer: connects the umbilical vein to the inferior vena cava, bypassing the liver becomes ligamentum venosum phrenic nerve correct answer: innervates the diaphragm and pericardium S3 heart sound correct answer: Increased ventricular filling pressure (e.g., mitral regurgitation, HF), common in dilated ventricles normal in kids and pregnant women S4 heart sound correct answer: atrial kick late diastole, right before S1 best heard at apex in LLD position High atrial pressure. Stiff/hypertrophic ventricle (aortic stenosis, restrictive cardiomyopathy) Always abnormal atria contract correct answer: a wave of JVP c wave correct answer: RV contraction (closed tricuspid valve bulging into atrium) wave of JVP x descent correct answer: JVP wave corresponding to downward displacement of closed tricuspid valve during rapid ventricular ejection phase reduced or absent in tricuspid regurge V wave correct answer: JVP wave corresponding to inc'd RA pressure due to filling against closed tricuspid valve y descent correct answer: JVP wave corresponding to RA emptying into RV absent in cardiac tamponade plusus parvus et tardus correct answer: pulses are weak with delayed peak Aortic stenosis PR interval correct answer: 0.12-0.20 seconds 120 milliseconds QT interval length correct answer: 9 - 11 squares = .36 to .44 seconds Hypokalemia correct answer: U wave present on ECG Mg sulfate correct answer: for torsades de pointe, hypokalemia (can lengthen QT and cause torsades), and pre-eclampsia (prevent seizures) Romano-Ward syndrome correct answer: -Congenital long QT syndrome -Autosomal dominant, pure cardiac phenotype (no deafness). Jervell and Lange-Nielsen syndrome correct answer: -Congenital long QT syndrome -Autosomal recessive, sensorineural deafness Brugada syndrome correct answer: -Autosomal dominant disorder affecting Na channels most common in Asian males. -ECG pattern of pseudo-right bundle branch block and ST elevations in V1-V3 (anterior ventricular septum) -inc risk of ventricular tachyarrhythmias and sudden cardiac deatgh Prevent SCD with implantable cardioverter-defibrillator (ICD). Wolff-Parkinson-White Syndrome correct answer: Most common type of ventriuclar pre-excitation sydnrome. Abnormal fast accessory conduction pathway from atria to venricle bypasses the rate-slowing AV node causing a delta wave and widening QRS with shortened PR interval. Could lead to a reentrant circuit and suprvaventicular tachy. First degree AV block correct answer: - PRI 5 boxes/.20 sec (200 msec) - Fixed but prolonged PRI (consistent but long) - normally get bradycardia here second degree AV block mobitz type 2 correct answer: -PR interval is constant -atrial conduction to ventricle is intermittent: dropped QRS without increasing PR interval length -disease below AV node in His bundle may progress to 3rd degree/complete AV block Second Degree AV Block Mobitz Type 1 (wenckebach) correct answer: Progressive lengthening of pr interval leading to dropped QRS third degree AV block correct answer: The atria and Ventricles are totally dissociated. -So, the QRSs and the P waves have no relation to each other. PCWP correct answer: 4-12 mmHg est of LA pressure Williams Syndrome correct answer: a genetic condition