Introduction: Cardiac resynchronization therapy (CRT) is a widely used method in the treatment of symptomatic patients with advanced heart failure and LBBB. Its beneficial impact on the reduction of left ventricular (LV) volumes has already been shown. (1, 2) The aim of this study was to determine if echocardiographic optimization of CRT pacing intervals (ECHO) after CRT device implantation has a favorable impact on LV volume change compared to electrocardiographic optimization (ECG).

Patients and Methods: An overall of 147 patients with implanted CRT according to guidelines were included in this study and divided into two groups according to the CRT optimization method (N=70 in ECG arm an N=77 in ECHO arm). ECG optimization was performed using 12-lead electrocardiogram, fusion-optimized intervals, intracardiac electrogram-based algorithms and electrocardiographic imaging. ECHO optimization implied correction of atrioventricular, inter- and intraventricular dyssynchrony using echocardiographic imaging. The change in LV end-diastolic (EDV), end-systolic (ESV) and stroke volume (SV) as well as LV ejection fraction (EF) was compared between groups, before and 6 months after CRT implantation.

Results: EDV and ESV significantly decreased and EF increased in both groups. In the ECHO a statistically significant reduction in EDV compared to ECG was present (p=0.028). According to greater EDV reduction, SV significantly decreased in ECHO (p=0.026). No significance was observed in ESV change between groups (p=0.063) (Table 1).

Conclusion: ECHO optimization of CRT leads to a more significant reduction of EDV compared to ECG optimization after 6 months of follow up.