I'm a 50 year old male that excercises 3 to 5 times per week. In April 2007, I began to develop chest pain while excercising. The frequency increased significantly in October 2007. In October thru December 2007 I went through a serious of stress tests, nuclear stress test, echo cardiograms, and a catherization. The process validated that I have Excercised Induced LBBB and that I feel it when it occurs. My cardiologist debated on the cause. The catherization indicated the major arteries to be normal, the heart is normal size and shape. One of the cardioligist specialized in arythmias reviewed the ECGs and felt they all had normal waves except when the LBBB occurred and after the LBBB the waves would return to normal. He felt that there may be a blockage in a small artery that the catherization could not see. The other 2 cardiologist did not agree and felt the problem was most likely electrical.
In October 2007, my heart rate ranged from 145 to 155 when the LBBB would occur only while running. It would disapppear in 5 to 10 minutes after I stopped excercing. Then I could continue my work out without further incident. I completed all of the test mentioned above over a course of 3 months and by January 2008 the LBBB would occur when my heart rate was in a ranger of 135 to 145.
Now it's June 2008, the LBBB occurs with my heart rate in the range of 105 to 120. I can no longer run because my heart rate hits this level within 5 minutes. I now excercise on an elliptical machine but I experience the LBBB within the first 10 to 20 minutes. I slow down and wait for it to pass then continue on with my workout. I've never had the LBBB occur more than once during a single workout. I use a polar heart monitor to check my heart rate.
Is the lowering hr triggering the LBBB a major concern? What is the potential impact? Are there additional test that can be done to determine the cause of the LBBB? Can you give me any additional advice?