Introduction: Biventricular pacing (BIV) has been established as a credible adjuvant treatment for patients with moderate-to-severe systolic heart failure (class III-IV of the NYHA classification) and Left bundle branch block (LBBB), which results in acute hemodynamic, neurohormonal and functional improvements, ventricular remodeling and has significant impact on survival and symptomatic improvement. Based on the current guidelines (ESC/AHA/ACC), several studies have demonstrated a failure to respond to CRT both with clinical criteria and using reverse remodeling (20-30% and 30-40%, respectively of the implanted patients). Consequently, imaging based measures of dyssynchronous myocardial contraction have been intensively investigated with the aim of improving the prediction of response to therapy. In this study, we hypothesized that RT3DE may be a robust technique in assessing mechanical synchronicity in heart failure patients and may be effective in identifying patients who might benefit from BIV.
Methods: 48 consecutive heart failure patients were screened with routine echocardiography, 35 (72%) of which were eventually included in the study. An additional 35 healthy subjects age and sex matched were recruited as a control group. Twenty patients from the heart failure group received biventricular pacemakers and were followed up to 6 months. The response to CRT was defined as either improvement in the NYHA class or reduction of the end-systolic volume >15%. Tissue Doppler imaging and Real time 3D data were obtained for all subjects and evaluation of volumes, ejection fraction and systolic dyssynchrony index was performed.
Results: Of 35 heart failure patients, 5 (14%) had mild, 7 (20%) moderate and 23 (66%) severe systolic dysfunction based on the EF calculation (45-50%, 45-35% and <35% respectively). The SDI was 11.2±2.2, 13.7±3.2 and 17.3±4 (%) respectively, while in the control group it was 9.8±2.1. The QRS length was <120ms in 29%, 120-140ms in 26% and >140ms in 45% of the patients.
Conclusions: Real Time Three-Dimensional Echocardiography is a robust technique, which can be used to accurately and effectively assess global and regional mechanical dyssynchrony in heart failure patients.
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.