asymptomatic LBBB - long term prognosis?

[jswim789]

I was diagnosed with LBBB about a year ago.  I'm basically asymptomatic - it was an incidental finding.  I've had an echo and my LVEF was about 50%.  Low, but not terribly concerning at this point.  I've read a lot of papers and articles, but they are largely focused on symptomatic LBBB with ejection fractions down below 35%.  My question is what might I expect in the future?  Will my ejection fraction decrease?  Or stay the same?  I'm reasonably fit and heart health conscious, but I don't go overboard.  Am I at higher risk for future problems, so should I make an extra effort there?  Or continue the daily glass of red wine and forget I ever heard about LBBB?

I feel a bit like I'm in no man's land.  I have no symptomatic issues, yet I have a "problem".

[CCFHeartMD24]

An echocardiogram can look at a variety of things, including LVEF, right ventricular function, valve function, diameters/volumes of heart chambers, vessels going into and out of the heart (such as the IVC and aorta), etc.

CRT works by placing a pacemaker lead in the right ventricle, as well as the left ventricle. These two leads pace at the same time, ensuring that your heart pumps in a synchronous manner (as opposed to the right ventricle pumping before the left ventricle, as in LBBB). There are a variety of ways in which the two leads can pace; they can be programmed to pace in sync with your internal pacing (which is preferred) or in it's own rhythm (as in certain people with more complex arrhythmias and conduction disease). Your electrophysiologist would make this determination.

[jswim789]

Thank you very much for the response.  Question: what does the cardiologist look for in the annual echo cardiogram?  LVEF?

And this is a side question: does CRT replace your heart's internal pacing completely, or does it synchronize with the heart's internal pace?  I.e., with LBBB, would it essentially replace only the broken bundle branch, or does it replace all the electrical pacemaking and wiring in the heart?

[CCFHeart MD25]

Generally speaking, LBBB should be followed with anual echocardiograms. You are correct that people with symptoms of heart failure (shortness of breath, leg swelling, feeling tired, etc) and a low ejection fractio associated with a LBBB have options that may improve things for them (a special type of pacemaker called cardiac resynchronization therapy, or CRT). On the other hand, many people with a LBBB never have any consequences. Either way, it should not be "forgotten", and you should follow with a cardiologist.