What is the hazard ratio of right bundle branch block?
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Dr. Sukhvinder, You have given me a very good example about smoking to explain to me the hazard ratio number. Could you give me the correct meaning what would be the hazard ratio for rbbb for each 100 patients as per the Coppenhagen City study ? Thank you.
Posted Tue, 11 Feb 2014 in Hypertension and Heart Disease
Answered by Dr. Sukhvinder Singh 1 hour later
Brief Answer: please see details Detailed Answer: Dear Sir As per Copenhagen study, Hazard ratio for all cause mortality (death) is 1.31 and for heart attacks 1.37 in men. The hazard ratio for pacemaker insertion was 2.17. 1. For 100 subjects with RBBB the death rate will be 1.31 times as for those without RBBB. Now the actual number depends upon the death rate in those without RBBB. For example if 10 deaths occur in 10 years in 100 subjects without RBBB, then 13 deaths will take place in 10 years in those 100 with RBBB. 2. The hazard ratio for heart attack in men was not statistically significant. That means this could have been a chance occurrence rather than true effect of RBBB. Surprisingly, the Hazard ratio for heart attack was significant in ladies. This could not be explained by the authors of study. 3. The chances of pacemaker insertion was 2.17 times more in those with RBBB. But in absolute terms only 12 subjects got a pacemaker inserted over a period of ~21 years among the 166 subjects (with RBBB). This number would be 5.5 for similar number of controls without RBBB. hence over a period 21 years only 6-7 persons out of 166 will get additional pacemaker insertion. Hope this clarifies the issue. Feel free to discuss further. Sincerely Sukhvinder
Follow-up: What is the hazard ratio of right bundle branch block? 1 hour later
This is my ecg taken now. Cardiologist said that my previous ecg was of the same result. Please could you tell me your comments on this? What is your medical feedback. Thanking you.
Answered by Dr. Sukhvinder Singh 1 hour later
Brief Answer: please see details Detailed Answer: Dear Sir This ECG shows normal sinus rhythm at a rate of ~90 bpm, PR interval of ~ 160 ms, Complete RBBB with QRSD of ~ 130 ms. If the subject has no symptoms and complaints, his clinical examination is normal and his x-ray chest is also normal, I would not do any further work up. However if there is anything positive out of these three, I would order a cardiac ultrasound (Echocardiogram). If cardiac ultrasound is normal and there is no symptoms suggestive of complete heart block (syncope or pre-syncope), I would not investigate further. A history of syncope, would further warrant opinion of an elctrophysiologist and may be electrophysiological study. I explained all the possible scenarios. Hope this helps. Sincerely Sukhvinder
Follow-up: What is the hazard ratio of right bundle branch block? 8 minutes later
Is this a benign condition in the absence of an underlying cause and if this same ecg result has been present for the past 5 years when i did the ecg for the first time. There are no symptoms at all and echo is fine. Why did my cardiologist mention that the QRS is 120 and not as you said 130. Should i be worried and is there a possibility that this could be a normal variant and benign. At which QRS value would this need pacemaker ? Should i be worried doing strenuous exercise knowing that i have always had this with no symptoms at all ..
Answered by Dr. Sukhvinder Singh 14 minutes later
Brief Answer: please see details Detailed Answer: Dear Sir 1. The duration of QRS is ~130ms. It is more than 3 small squares to me, hence >120 ms. 2. It is likely to be a normal variant (benign) in the absence of symptoms and normal ECHO. If it is a part of degenerative (aging) disease of your conduction system, is something which none can answer with surety. Only logical inferences can be drawn, like, if it same for 5 years, then it is likely to be very slow process. The need for pacemaker in this process may arise after many years (or may not arise at all). How many years in your case? None knows. The indication for pacemaker will be development of symptoms and further progression to AV block or complete heart block. Isolated RBBB can not be an indication for pacemaker (whatsoever the QRS duration may be), especially so in absence of symptoms. 3. If you are already doing certain level of exercise without symptoms you can continue to do so even now. Sincerely Sukhvinder
Follow-up: What is the hazard ratio of right bundle branch block? 49 minutes later
Should i be worried ? Doctor says its benign and to continue to exercice normally. Do you have any information source which mentions that rbbb (not just IRBBB) in young individuals with QRS 130 can be an incidental finding in the absence of an underlying cause. I cant sleep because i am very worried.
Answered by Dr. Sukhvinder Singh 9 hours later
Brief Answer: please see details Detailed Answer: Dear Sir 1. You must not be worried, Because even if , even if we imagine that there are some increased chances of pacemaker insertion/ death, it is not known that you will be among the ones who will have increased risk or normal risk (out of subjects with RBBB ). Second till now it is not clearly known that the minimally increased risk is definitely there or not; it is still controversial. Third, If it is there, we can not change anything about it as yet. 2. A number of studies prior to Copenhagen study mentions that complete RBBB with normal heart and no symptoms, is benign. You can have the exact references from the editorial regarding Copenhagen study itself. Please refer to following links. WWW.WWWW.WW 3. Please continue your exercise and healthy heart practices as I mentioned in my previous discussion. sincerely Sukhvinder