Get your Health question answered in 3 easy steps
A Doctor will be with you shortly
Ask a Doctor Now
120 Doctors are Online

Diagnosed with RBBB. ECG showed incomplete rbbb and left axis deviation. Should I be worried?

User rating for this question
Very Good
Answered by

Cardiologist, Interventional
Practicing since : 1998
Answered : 411 Questions
Hi I am asking on behalf of my 18 year old son, who was diagnosed with RBBB after a faint about 18 months ago. We went to see a cardiologist who said that the ECG showed incomplete right bundle branch block (QRS 118ms) and left axis deviation. An echo was done at this time, and this was normal. As my son was taking methylphenidate he agreed to see him in a years time for a review. We have just been to see him again, and this time he said at the appointment that the RBBB was 'borderline'. He later wrote us a letter to say that the RBBB read as significant on the ECG on that day, but that the left axis deviation was less apparent than at the first ECG and the axis was within normal limits. He also said that the two ECGs 1 year apart were more or less identical. My son's pulse may have been rather lower on the second ECG I think, because he has been going to the gym - his pulse was only 51 beats per minute. The reason for my query is whether we should be worried that the RBBB is now significant or complete, rather than incomplete. I an not too worried as I know that the numbers on the ECG can be different from one time to another, and his QRS complex length was nearly 120ms the first time it was taken anyhow. I guess I am just looking for some reassurance. All other intervals were normal, as far as I know and the cardiologist did not seem concerned. Many thanks for your help XXXXXXX my e-mail address is YYYY@YYYY

Posted Thu, 17 Jan 2013 in Hypertension and Heart Disease
Answered by Dr. Prabhakar C Koregol 17 hours later

I would more or less agree with whatever your doctor and you understand and explained. Yes, as lone finding RBBB does not have much of clinical significance especially if Echocardiogram is normal. If echo is normal you don't have to worry.

Yes when RBBB develops it goes in from the gradual increase from Normal QRS to incomplete and then complete RBBB and on reaching XXXXXXX duration it doesn't further increase.

But what remains to be answered is what caused the faint. If it was single episode and most of the basic investigations are normal you don't have to worry. But if faint/syncope is recurrent he needs further evaluation including EP (electrophysiological) studies/Holter monitoring.

Hope this helps you. Do write back for follow up queries that you may have.

Above answer was peer-reviewed by
Share on Facebook
Share on Twitter
Share on Google+
Question is related to
Diseases and Conditions

The user accepted the expert's answer

Ask a Cardiologist

© Ebix, Inc. All Rights Reserved.
All the information, content and live chat provided on the site is intended to be for informational purposes only, and not a substitute for professional or medical advice. You should always speak with your doctor before you follow anything that you read on this website. Any health question asked on this site will be visible to the people who browse this site. Hence, the user assumes the responsibility not to divulge any personally identifiable information in the question. Use of this site is subject to our Terms & Conditions
Already Rated.
Your rating:

Ask a Doctor