Exam Prep For
NBME CBSE
** Expert-Verified Explanation
** Questions with Verified Answer
** New Edition | 2026-2027 Updated
** 100% Guaranteed Pass
** 100% Correct Answers | Graded A+
,ductus venosus connects the umbilical vein to the inferior vena cava, bypassing the liver
becomes ligamentum venosum
phrenic nerve innervates the diaphragm and pericardium
S3 heart sound Increased ventricular filling pressure (e.g., mitral regurgitation, HF), common in
dilated ventricles
normal in kids and pregnant women
S4 heart sound 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 a wave of JVP
c wave RV contraction (closed tricuspid valve bulging into atrium) wave of JVP
x descent JVP wave corresponding to downward displacement of closed tricuspid valve
during rapid ventricular ejection phase
reduced or absent in tricuspid regurge
V wave JVP wave corresponding to inc'd RA pressure due to filling against closed
tricuspid valve
y descent JVP wave corresponding to RA emptying into RV
absent in cardiac tamponade
plusus parvus et tardus pulses are weak with delayed peak
Aortic stenosis
PR interval 0.12-0.20 seconds
120 milliseconds
QT interval length 9 - 11 squares = .36 to .44 seconds
, Hypokalemia U wave present on ECG
Mg sulfate for torsades de pointe, hypokalemia (can lengthen QT and cause torsades), and
pre-eclampsia (prevent seizures)
Romano-Ward syndrome -Congenital long QT syndrome
-Autosomal dominant, pure cardiac phenotype (no deafness).
Jervell and Lange-Nielsen syndrome -Congenital long QT syndrome
-Autosomal recessive, sensorineural deafness
Brugada syndrome -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 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 - 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 -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) Progressive lengthening of pr interval leading to dropped QRS
third degree AV block The atria and Ventricles are totally dissociated.
-So, the QRSs and the P waves have no relation to each other.
NBME CBSE
** Expert-Verified Explanation
** Questions with Verified Answer
** New Edition | 2026-2027 Updated
** 100% Guaranteed Pass
** 100% Correct Answers | Graded A+
,ductus venosus connects the umbilical vein to the inferior vena cava, bypassing the liver
becomes ligamentum venosum
phrenic nerve innervates the diaphragm and pericardium
S3 heart sound Increased ventricular filling pressure (e.g., mitral regurgitation, HF), common in
dilated ventricles
normal in kids and pregnant women
S4 heart sound 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 a wave of JVP
c wave RV contraction (closed tricuspid valve bulging into atrium) wave of JVP
x descent JVP wave corresponding to downward displacement of closed tricuspid valve
during rapid ventricular ejection phase
reduced or absent in tricuspid regurge
V wave JVP wave corresponding to inc'd RA pressure due to filling against closed
tricuspid valve
y descent JVP wave corresponding to RA emptying into RV
absent in cardiac tamponade
plusus parvus et tardus pulses are weak with delayed peak
Aortic stenosis
PR interval 0.12-0.20 seconds
120 milliseconds
QT interval length 9 - 11 squares = .36 to .44 seconds
, Hypokalemia U wave present on ECG
Mg sulfate for torsades de pointe, hypokalemia (can lengthen QT and cause torsades), and
pre-eclampsia (prevent seizures)
Romano-Ward syndrome -Congenital long QT syndrome
-Autosomal dominant, pure cardiac phenotype (no deafness).
Jervell and Lange-Nielsen syndrome -Congenital long QT syndrome
-Autosomal recessive, sensorineural deafness
Brugada syndrome -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 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 - 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 -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) Progressive lengthening of pr interval leading to dropped QRS
third degree AV block The atria and Ventricles are totally dissociated.
-So, the QRSs and the P waves have no relation to each other.
