Perspective:

CRT in patients with LBBB is associated with improved functioning and reduced mortality. Unfortunately, there is a significant number of nonresponders, and not an insignificant failure rate of implantation due to anatomic limitations. His-bundle pacing has provided an alternative to traditional biventricular pacing. While achieving more physiological pacing in many, His-bundle pacing itself has had a relatively high failure rate and suboptimal long-term performance. Several prior observational studies have shown the feasibility and utility of LBBP, but the present study is the first to provide a prospective, randomized evaluation. Direct LBBP offers the possibility of pacing distal to the site of LBBB, as the electrode penetrates the interventricular septum often achieving a narrower paced QRS with low stable pacing thresholds. Randomized trials are needed to compare the long-term effects of LBBP and BiVP on functional status and survival in patients with heart failure and LBBB. Different approaches may be required depending on the location of the block and the underlying cardiomyopathic process before widespread adoption, but at this time, LBBP is at least offering an attractive alternative to unsuccessful or suboptimal BiVP.