Cubs' DeRosa and the Management of SVT

Mark DeRosa, the Cub's second baseman, was reported today to have flown back to Chicago from spring training in Mesa Arizona to be "examined by a cardiologist at Northwestern Meemorial Hospital, but only expects to miss one week of camp."

That should be about right. After all, he has a very curable condition called "SVT" - short for supraventricular tachycardia.

My bet: he'll be "cured" before the close of business today and use the rest of the week to convalesce.

On second thought - he'll probably be playing again Monday.

Most likely, he has garden-variety AV nodal reentrant tachycardia, a loop-the-loop heart rhythm caused when two halves of the normal AV node (which connects the top and bottom chambers of the heart electrically) create a circular path around which the electricity can travel quickly - to the tune of about 150-200 beats per minute typically. One pathway usually conducts quickly, and the other, more slowly. The fact that he can do "manuvers" to stop the rhythm (usually a "Valsalva maneuver" - forced expiration against a closed mouth) - is very suggestive that this is this cause for his racing heart beats. The straining maneuver causes slowed conduction through the pathways, but the slower-conducting pathway occassionally stops its conduction briefly, allowing the regular rhythm to resume.

Catheter ablation, or cauterizing (burning) the slower-conducting pathway in the AV node, when performed correctly, has a very high cure rate and relatively low complication rate, but involves about a two- to three-hour procedure where wires are passed throught the veins in the legs to the heart, and the location of the slow pathway cauterized to destroy the extra-conducting pathway. No long-term medications are required. Certainly, for the person unwilling to risk the procedure, medications (like beta blockers or calcium channel blockers) can be used to help control the arrhythmia by blunting heart rate response - not a likely scenario for a pro-baseball player to accept.

I wish Mr. DeRosa the best of luck, and look forward to seeing him back on the field soon.

-Wes

UPDATE: 27 Feb 2008 17:00 - It's sometimes nice to say I told you so. (Heh, this wasn't a tough call - but I think DeRosa's making the right choice here...)

ADDENDUM: 1 Mar 2008: All's well that ends well.