A study has just been published which demonstrates how His-bundle pacing allows the healing of heart failure caused by attachment of pacemaker leads to the heart in the classic right ventricular location.
The stated objective of this study, by Dr. Parikshit S. Sharma, et. al. of four universities, is “to assess the feasibility and outcomes of HBP [His-bundle pacing] in CRT [cardiac resynchronization therapy] eligible or failed patients.”
Key to understanding this study is that HBP was done as “a rescue strategy” for patients suffering from heart failure including that caused by right ventricular pacing (RVP) — sometimes followed by CRT, which adds a lead to pace the left ventricle. Since the 1960’s, the placement of a pacemaker lead in the right ventricle has been common practice.
This bypasses the His-bundle, the control system that choreographs normal ventricular contraction. CRT also bypasses the His-bundle and “up to a third, of patients treated with biventricular pacing do not derive clinical benefit, and indeed, some worsen,” as the study’s text notes. However, development of clinical His-bundle pacing, first published in 2000, has been a game changer for patient outcome.
The new study shows overwhelming results for patients already using either an RVP attached pacemaker, or CRT. His-bundle pacing was successfully achieved in 90% of needy patients. While its breadth and depth may be called breakthrough analysis on behalf of patients in heart failure, it also concurs with many previously published findings.
The aggregate of it all poses a rather glaring question. Since right ventricular pacing can cause heart failure, why not make His-bundle pacing the preferred method from the outset, to provide a more natural and sustainable heartbeat? A corollary question follows. Knowing what we know by now, how can it be just and right for patients to be treated in the first place with ventricular pacing which bypasses the His bundle?
We commend this multi-university hospital team of physicians for demonstrating that HBP is the way to heal hearts in failure caused by certain unnatural heart rhythms (including bundle branch block, as well as RVP). When it comes to one’s heart, the ability to provide a pound of cure is just as worthy as the medical industry’s well known but as yet underutilized, critical ounce of prevention. Shout it all from the housetops.
Well done Dr. Dandamudi, great endeavors always endure adversity.
My husband’s team attempted His bundle pacing but aborted the effort in surgery stating that the power required would necessitate replacing the pace maker in a few years. Given the findings here, I get the impression that battery drain is not a common phenomenon when connecting to the His bundle?
The average His pacing threshold, according to the literature, is 1.3 or 1.5 volts, depending on the study. It is 0.5 volts in some patients, so there is overlap with “conventional pacing” known to cause “pacing induced heart failure.” Once a patient gets heart failure, as you can see, the recommendation is biventricular pacing, called CRT, resulting in more rapid battery drain than His pacing. Unfortunately, CRT continues to result in 30% “non-responders.” So His pacing practitioners don’t think increased battery drain is a reason to withhold treatment – no non-responders and less heart failure hospitalization. Hope that helps.