Ans- Smooth parts outflow tract of left and right ventricles

NBME CBSE

Bulbus cordis (Ans- Smooth parts (outflow tract) of left and right ventricles

endocardial cushions (Ans- Atrial septum, membranous interventricular septum; AV and semilunar valves

neural crest

left horn of the sinus venosus (Ans- coronary sinus

posterior, sub cardinal, and supra cardinal veins (Ans- IVC

Right common cardinal vein and right anterior cardinal vein (Ans- SVC

Right horn of sinus venosus (Ans- Smooth part of right atrium (sinus venarum)

Patent foramen ovale (Ans- failure of septum primum and septum secundum to fuse after birth

Transposition of the great vessels Tetralogy of Fallot Persistent truncus arteriosus (Ans- Conotruncal abnormalities associated with failure of neural crest cells to migrate

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ductus venosus (Ans- connects the umbilical vein to the inferior vena cava, bypassing the liver

becomes ligamentum venosum

phrenic nerve (Ans- innervates the diaphragm and pericardium

S3 heart sound (Ans- Increased ventricular filling pressure (e.g., mitral regurgitation, HF), common in dilated ventricles

normal in kids and pregnant women

S4 heart sound (Ans- 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 (Ans- a wave of JVP

c wave (Ans- RV contraction (closed tricuspid valve bulging into atrium) wave of JVP

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x descent (Ans- JVP wave corresponding to downward displacement of closed tricuspid valve during rapid ventricular ejection phase

reduced or absent in tricuspid regurge

V wave (Ans- JVP wave corresponding to inc'd RA pressure due to filling against closed tricuspid valve

y descent (Ans- JVP wave corresponding to RA emptying into RV

absent in cardiac tamponade

plusus parvus et tardus (Ans- pulses are weak with delayed peak

Aortic stenosis

PR interval (Ans- 0.12-0.20 seconds

120 milliseconds

QT interval length (Ans- 9 - 11 squares = .36 to .44 seconds

Hypokalemia (Ans- U wave present on ECG

Mg sulfate (Ans- for torsades de pointe, hypokalemia (can lengthen QT and cause torsades), and pre-eclampsia (prevent seizures)

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Romano-Ward syndrome (Ans- -Congenital long QT syndrome -Autosomal dominant, pure cardiac phenotype (no deafness).

Jervell and Lange-Nielsen syndrome (Ans- -Congenital long QT syndrome -Autosomal recessive, sensorineural deafness

Brugada syndrome (Ans- -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) -increases risk of ventricular tachyarrhythmias and sudden cardiac death

Prevent SCD with implantable cardioverter-defibrillator (ICD).

Wolff-Parkinson-White Syndrome (Ans- 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 (Ans-

• PRI >5 boxes/.20 sec (200 msec)
• Fixed but prolonged PRI

(consistent but long)

• normally get bradycardia here

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