Department of Cardiology, the First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China; Institute of Cardiovascular Diseases of Yunnan Province, Kunming, Yunnan, China
Institute of Cardiovascular Diseases of Yunnan Province, Kunming, Yunnan, China
Department of Cardiology, the First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
Cardiovascular Division and Lillehei Heart Institute, University of Minnesota, Minnesota, USA
Department of Pharmacology, College of Basic Medicine, Kunming Medical University, Kunming, Yunnan, China
This study was supported by three grants from National Natural Science Foundation of China (81360044), Yunnan Science and Technology Committee (2013FB133 and Yunnan province National Science Foundation (2013FZ054). The authors declare no conflict of interest regarding.
Objective To evaluate left univentricular (LUV) pacing for cardiac resynchronization therapy (CRT) using a rate-adaptive atrioventricular delay (RAAVD) algorithm to track physiological atrioventricular delay (AVD). Methods A total of 72 patients with congestive heart failure (CHF) were randomized to RAAVD LUV pacing versus standard biventricular (BiV) pacing in a 1: 1 ratio. Echocardiography was used to optimize AVD for both groups. The effects of sequential BiV pacing and LUV pacing with optimized A-V (right atrio-LV) delay using an RAAVD algorithm were compared. The standard deviation (SD) of the S/R ratio in lead V1 at five heart rate (HR) segments (RS/R-SD5), defined as the “tracking index,” was used to evaluate the accuracy of the RAAVD algorithm for tracking physiological AVD. Results The QRS complex duration (132 ± 9.8 vs. 138 ± 10 ms, P vs. 50 ± 8 min, P vs. 2.5 ± 1.3 cm2, P vs. 68.3 ± 14.2 ms, P vs. 21,600 ± 2000 RMB, P vs. 21.4 ± 2.1 cm, P S/R-SD5 was 4.08 ± 1.91 in the RAAVD LUV pacing group, and was significantly negatively correlated with improved left ventricular ejection fraction (LVEF) (?LVEF, Pearson’s r = ?0.427, P = 0.009), and positively correlated with New York Heart Association class (Spearman’s r= 0.348, P = 0.037). Conclusions RAAVD LUV pacing is as effective as standard BiV pacing, can be more physiological than standard BiV pacing, and can decrease the average annual cost of CRT.