P1546Improvement of reverse remodelling by using ECG fusion optimized intervals (FOI) in cardiac resynchronization therapy: a randomized study

Abstract

Background: The additional beneft obtained by AV and VV interval optimization in cardiac resynchronization therapy (CRT) is still debated. Previous studies have shown acute beneft in hemodynamic parameters by ECG or echocardiographic based optimization. However, midterm randomized comparison between ECG optimization and default parameters is lacking. Objective: The aim of our study was to compare the response to CRT using FOI versus Nominal settings programming. Methods: A group of 180 consecutive patients, successfully implanted CRT were randomized to FOI versus Nominal settings. In FOI group, the AV and VV interval were optimized looking narrowest QRS with fusion from intrinsic conduction. Clinical response was defned as being alive and increase >10% at the 6 minutes walking test or a decrease in one category in NYHA functional class. Left ventricular (LV) reverse remodeling was defned as a decrease in >15% in LV end systolic volume at 12 months of follow up. Results: Mean age 65 +/- 10 years, 67% males, 37% ischemic cardiomyopathy, LV ejection fraction 26 +/- 7%, QRS 180 +/- 23 ms. By FOI, all patients showed significant shortening of the baseline QRS (p=0.025). At 12 months; clinical response and overall mortality were similar in both groups (p= NS). However, LV reverse remodeling was observed in 74% of FOI pts vs 53% in Nominal group (p= 0.019). In FOI group, more patients were classified as super-responders and fewer patients as negative responders after 12 months of therapy (fgure 1). Conclusion: Device optimization by ECG based on QRS width looking for fusion with FOI; achieve a shorter QRS at baseline and results in increased number of LV remodeling compared to Nominal settings.