Transcatheter mitral valve repair may reduce ventricular tachyarrhythmia burden

BOSTON — Transcatheter mitral valve repair may reduce the burden of ventricular tachyarrhythmia in older adults, according to data presented at the Heart Rhythm Society Annual Scientific Sessions.

According to the study background, mitral valve repair with a transcatheter system (MitraClip, Abbott Vascular) has been implemented to reduce severe mitral regurgitation in patients not eligible for surgery, and mitral regurgitation is associated with ventricular volume overload, which may result in enhanced electrical vulnerability. Researchers, therefore, investigated whether transcatheter mitral valve repair might affect ventricular arrhythmogenic burden.

Cathrin Theis

Cathrin Theis, MD, from II. Medical Clinic, department of electrophysiology, University Medical Center, Johannes Gutenberg-University, Mainz, Germany, and colleagues analyzed 189 patients who underwent transcatheter mitral valve repair at their institution.

Of those, 50 patients (mean age, 75 years; 41 men; mean left ventricular ejection fraction, 27%) had previously undergone implantation of an active cardiac rhythm device equipped with Holter monitoring, according to the researchers.

The primary outcome was ventricular tachyarrhythmia (VT) episodes, classified as nonsustained VTs (duration ≤ 30 seconds), VTs with cycle length of at least 300 ms, fast VTs (cycle length ≤ 300 ms) and ventricular fibrillation (cycle length ≤ 250 ms). Episodes were analyzed for 20 months before and after transcatheter mitral valve repair.

Theis and colleagues observed 98 sustained VT episodes in 18 patients during the observation period; 68 occurred before transcatheter mitral valve repair compared with 30 that occurred after repair (P = .015).

In addition, VTs with cycle length of at least 300 ms were reduced after transcatheter mitral valve repair (46 vs. 21; P = .046). Only one patient experienced recent-onset VT episodes after valve repair.

The researchers found no significant differences between before vs. after valve repair in fast VTs (11 vs. 5; P = .48), ventricular fibrillation (11 vs. 4; P = .11) or nonsustained VTs (56 vs. 49; P = .89).

“A decreased electrical ventricular vulnerability may be considered a marker of cardiac function improvement after [MitraClip] therapy with potentially positive consequences for the patients’ morbidity and mortality,” the researchers concluded. – by Erik Swain

Reference:

Theis C, et al. Abstract MP01-03. Presented at: Heart Rhythm Society Annual Scientific Sessions; May 13-16, 2015; Boston.

Disclosure: Theis reports no relevant financial disclosures.