PO-678-06 LEFT BUNDLE BRANCH AREA PACING INCREASES LEFT VENTRICULAR EJECTION FRACTION AND PREVENTS PACING-INDUCED CARDIOMYOPATHY IN THE LONG-TERM OBSERVATION

Abstract

There is scarcity of data on long-term impact of left bundle branch area pacing (LBBAP) on left ventricular (LV) function. To evaluate LV function in patients with over 1 year of LBBAP and substantial pacing burden. Patients with LBBP for any indication were prospectively followed; ventricular pacing burden > 40% and R/r wave in lead V1 at the final follow-up were the only inclusion criteria. Following measures of LV function were assessed at baseline and at the last follow-up: LV ejection fraction (EF), global longitudinal strain (GLS), peak strain dispersion (PSD), LV end-diastolic diameter and volume (LVEDd, LVEDV), and LV end-systolic diameter and volume (LVESd, LVESV). A total of 100 consecutive patients were studied: age 76.7 ±10 y., female 41%, follow-up 21 ±7 months and ventricular pacing burden 87.6 ±20%. At baseline 31 patients had CRT indications (LV EF < 50%). In the whole group an increase in LV EF (53 ±12% vs 56 ±12%) and decrease in LVEDV, LVESV, LVEDd and absolute GLS (74 ± 37 mm vs 70 ±35 mm, 37 ±30 mm vs 34 ±28 mm, 48 ±9% vs 47 ±9%, 16.6 ±5% vs 17.5 ±5%, respectively) were observed, but there was no change in LVESd (37 ±11 mm vs 37 ±9.5 mm). In the CRT group the EF improved from 39 ±10% to 45 ±12.5%, while in the non-CRT group there was no change in EF (60.7 ±6% vs 60.9 ±7%). No patient had decrease in LV EF > 10%. The LV synchrony assessed by PSD improved in CRT group (74.4 ±35 ms vs 60.5 ±22 ms) and remained stable in non-CRT group (49.2 ±21 ms vs 49.3 ±19 ms). Left bundle branch pacing preserves or improves left ventricular function in the long-term observation and might prevent development of pacing-induced cardiomyopathy.