endocardial cushions - Answer Atrial septum, membranous interventricular septum; AV
and semilunar valves
neural crest
left horn of the sinus venosus - Answer coronary sinus
posterior, sub cardinal, and supra cardinal veins - Answer IVC
Right common cardinal vein and right anterior cardinal vein - Answer SVC
Right horn of sinus venosus - Answer Smooth part of right atrium (sinus venarum)
Patent foramen ovale - Answer failure of septum primum and septum secundum to fuse
after birth
Transposition of the great vessels
Tetralogy of Fallot
Persistent truncus arteriosus - Answer Conotruncal abnormalities associated with failure
of neural crest cells to migrate
ductus venosus - Answer connects the umbilical vein to the inferior vena cava,
bypassing the liver
becomes ligamentum venosum
phrenic nerve - Answer innervates the diaphragm and pericardium
S3 heart sound - Answer Increased ventricular filling pressure (e.g., mitral regurgitation,
HF), common in dilated ventricles
normal in kids and pregnant women
S4 heart sound - 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 - Answer a wave of JVP
,c wave - Answer RV contraction (closed tricuspid valve bulging into atrium) wave of JVP
x descent - Answer JVP wave corresponding to downward displacement of closed
tricuspid valve during rapid ventricular ejection phase
reduced or absent in tricuspid regurge
V wave - Answer JVP wave corresponding to inc'd RA pressure due to filling against
closed tricuspid valve
y descent - Answer JVP wave corresponding to RA emptying into RV
absent in cardiac tamponade
plusus parvus et tardus - Answer pulses are weak with delayed peak
Aortic stenosis
PR interval - Answer 0.12-0.20 seconds
120 milliseconds
QT interval length - Answer 9 - 11 squares = .36 to .44 seconds
Hypokalemia - Answer U wave present on ECG
Mg sulfate - Answer for torsades de pointe, hypokalemia (can lengthen QT and cause
torsades), and pre-eclampsia (prevent seizures)
Romano-Ward syndrome - Answer -Congenital long QT syndrome
-Autosomal dominant, pure cardiac phenotype (no deafness).
Jervell and Lange-Nielsen syndrome - Answer -Congenital long QT syndrome
-Autosomal recessive, sensorineural deafness
Brugada syndrome - 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 - 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 - 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 - 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) - Answer Progressive
lengthening of pr interval leading to dropped QRS
third degree AV block - Answer The atria and Ventricles are totally dissociated.
-So, the QRSs and the P waves have no relation to each other.
PCWP - Answer 4-12 mmHg
est of LA pressure
Williams Syndrome - Answer a genetic condition characterized by mental retardation in
most regards but surprisingly good use of language relative to their other abilities, elfin
facies
Chromosome 7
assoc with supravalvular aortic stenosis
DiGeorge Syndrome - Answer Maldevelopment of 3 and 4 pharyngeal pouches, fascial
dysmorphia, cardiac shunt (trunks arteriosus, tetralogy of Fallot), lack of T-cells,
undeveloped paracortex
Corneal arcus - Answer Lipid deposits in the cornea. Common in the elderly, but
appears earlier in life with hypercholesterolemia
Stanford A aortic dissection - Answer Dissection of the ascending aorta
Tx with surgery
Stanford B aortic dissection - Answer Dissection of the descending aorta below the level
o the left subclavian artery
Tx: Beta Blockers then vasodilators
Left bundle branch block - Answer QRS> 120 msec
Deep, broad S waves in V1 and V2