Quiz 19: Answer

Echocardiogram: Aortic Arch View (Suprasternal notch view)

Question 1: What is abnormal in Panel 1?

Answer: (i) Left innominate vein is not see at the angle between the ascending aora and the origin of first arch vessel. (ii) Cross section of a second vessel is noted posterior to ascending aorta in addition to the usual right pulmonary artery.

Question 2: What vascular anomaly should be looked for?

Answer: Retroaortic innominate vein.

This is a rare entity noted in patient with Tetralogy of Fallot with Right aortic arch or when aorta has a "high" arch.

Clinical significance stems from rare clinical tales of the surgeon mistaking this retroaortic innominate vein for right pulmonary artery and places the BT shunt from subclavian artery to the innominate vein (& not to the right pulmonary artery).

Quiz #18 Answer: EKG - AV Block, Second Degree

2-day old baby (Tetralogy of Fallot) developed this rhythm during cardiac catheterization.
Question: What is this catheter-induced rhythm?

Answer: Second degree AV Block

Arrows indicate P waves. There is 2:1 conduction. The conducted P waves are conducted with a prolonged PR interval (HR 83 bpm; PR interval 180-190 ms).

(At the onset, this was 3rd degree AV Block. This occurred during catheter manipulations in RV, attempting to cross a severely stenotic pulmonary valve. Intermittently, the catheter cross the VSD and entered the aorta. Presumably, the His bundle was affected during one of these times. Rhythm recovered spontaneously  to 2nd degree over time. Because the baby was unstable with ventricular rate of 83 bpm, Isoproterenol infusion was started after recording this EKG. Sinus rhythm was restrored after ~ 8 -12 hrs)

(Click on the image to enlarge)