RBBB as an indication for coronary angiography

In 2017 European Society of Cardiology (ESC) guidelines on ST-segment elevation myocardial infarction (STEMI) management, the presence of right bundle branch block (RBBB), similarly to left bundle branch block (LBBB), is now an indication for urgent coronary angiography in patients with symptoms of myocardial ischemia. What is this based on? Should every patient with features of myocardial infarction (MI) and RBBB in electrocardiogram (ECG) undergo urgent coronary angiography? Does it apply only to patients with a new block or also to those with a preexisting block?

Zaza Iakobishvili, MD, PhD: That is a very good question. It bothers a lot of cardiologists. This recommendation is based on one study. It comes from the PRAGUE study group and Professor Widimsky. They showed in the 2012 paper that patients with RBBB had worse prognosis than patients without it.

The way it worked was that it was added to the guidelines that RBBB is an indication to primary percutaneous coronary intervention (PCI) in an appropriate clinical setting. It is very important because patients with preexisting RBBB without clear signs of MI probably would not go for primary PCI, but a patient with new-onset or presumably new-onset RBBB immediately has to go to primary PCI.

I think it is a very important addition and there will be a need to pressure for further surveillance of this guideline inclusion to see if it works or not. But I think it is very important.