Abstract 272: The Role of Diabetes Mellitus in Cardiac Resynchronization Therapy Response in Patients with Optimal Anatomical and Electrical Left Ventricular Lead Location.

Abstract

Background: While optimal left ventricular (LV) lead location is known to predict a favorable response to cardiac resynchronization therapy (CRT) therole of underlying Diabetes Mellitus (DM) in this patient population remains uncertain. Methods: We analyzed a prospective cohort of 180 CRT patients. Anatomical lead location was confirmed by coronary venograms and chest radiographs. LV lead electrical delay (LVLED) was measured from QRS onset on surface ECG to the first sensed signal of the LV lead, and standardized based on native QRS width. Echocardiographic response was evaluated at baseline and 6 months. Time to first heart failure hospitalization or death was assessed over 3 years. Results: 100 patients (Age 68.2 ± 12.3 years; Baseline LVEF 23.2 ± 6.8 %, NYHA 3.0 ± 0.3) with optimal LV lead location defined as ‘long’ LVLED(LVLED>50%) with non-apical and anterolateral, lateral or posterolateral lead position were selected from the original cohort. They were further categorized by the presence (n=38) or absence (n=62) of DM. Baseline clinical and echocardiographic characteristics were similar between groups except for a higher incidence of hypertension in diabetics (94.7% vs. 58.1%, p <0.001) and longer LVLED in non-diabetics (81.7 ± 16.5 vs. 74.8 ± 14.8, p=0.03). DM was significantly associated with time to first heart failure hospitalizations (Fig 1A) and a composite of all-cause mortality and heart failure (Fig1B) by the Kaplan-Meir method. However on multivariate cox regression Diabetes was not an independent predictor of response. Echocardiographic response was similar across both groups. Conclusion: In CRT patients with optimal lead location and Diabetes, there is a trend towards worse outcomes. This could be the setting of Diabetes related cardiomyopathy and the higher incidence of ischemic heart disease in diabetics.