h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Today I was diagnosed by a cardiologist with Rate Related Left Bundle Branch Block (RR LBBB) based on a 24 hr holter monitor test. I am scheduled for an ECG next week to further investigate. These tests were ordered to solve why I am passing out. I have been really light headed and fell to the floor five times since April (6 months). The cardiologist said the RR LBBB would not cause me to pass out, but your article does reference dizziness and collapse being caused by the block. Do you have more information on this or any advice for me? I really would like to be prepared with more questions for the cardiologist when we meet in two weeks.

I can't really give you specific medical advice, but it's fair to say that only some forms of heart block will cause collapse/dizziness - these are mainly the AV blocks. In these cases, the block slows down the heart to the point that the blood pressure drops off. As I've said in the entry, bundle branch blocks tend not to cause symptoms, and when they do it is in the presence of an intermittent AV block or a fast heart rhythm. Thus, I'd imagine that your LBBB isn't the sort that causes dizziness by itself - you should ask your cardiologist to clarify for you.

Alex

Thank you for clarifying. My cardiologist said I had a fast heart rate that often gets out of sync because of the RR LBBB, but he did not say anything about a slow rate. Something I will have to ask him about.
After reading your reply, this article and a few other articles, I feel I understand the condition a little better and I am prepared to ask relevant educated questions at my cardiologist appointment at the end of the week.
Thank you.

Bear in mind, in my last post:

"bundle branch blocks tend not to cause symptoms, and when they do it is in the presence of an intermittent AV block or a fast heart rhythm"

Alex