Acute Beneficial Hemodynamic Effects of a Novel 3D-Echocardiographic Optimization Protocol in Cardiac Resynchronization Therapy

Abstract

BackgroundPost-implantation therapies to optimize cardiac resynchronization therapy (CRT) focus on adjustments of the atrio-ventricular (AV) delay and ventricular-to-ventricular (VV) interval. However, there is little consensus on how to achieve best resynchronization with these parameters. The aim of this study was to examine a novel combination of doppler echocardiography (DE) and three-dimensional echocardiography (3DE) for individualized optimization of device based AV delays and VV intervals compared to empiric programming.Methods25 recipients of CRT (male: 56%, mean age: 67 years) were included in this study. Ejection fraction (EF), the primary outcome parameter, and left ventricular (LV) dimensions were evaluated by 3DE before CRT (baseline), after AV delay optimization while pacing the ventricles simultaneously (empiric VV interval programming) and after individualized VV interval optimization. For AV delay optimization aortic velocity time integral (AoVTI) was examined in eight different AV delays, and the AV delay with the highest AoVTI was programmed. For individualized VV interval optimization 3DE full-volume datasets of the left ventricle were obtained and analyzed to derive a systolic dyssynchrony index (SDI), calculated from the dispersion of time to minimal regional volume for all 16 LV segments. Consecutively, SDI was evaluated in six different VV intervals (including LV or right ventricular preactivation), and the VV interval with the lowest SDI was programmed (individualized optimization).ResultsEF increased from baseline 23±7% to 30±8 (p<0.001) after AV delay optimization and to 32±8% (p<0.05) after individualized optimization with an associated decrease of end-systolic volume from a baseline of 138±60 ml to 115±42 ml (p<0.001). Moreover, individualized optimization significantly reduced SDI from a baseline of 14.3±5.5% to 6.1±2.6% (p<0.001).ConclusionsCompared with empiric programming of biventricular pacemakers, individualized echocardiographic optimization with the integration of 3-dimensional indices into the optimization protocol acutely improved LV systolic function and decreased ESV and can be used to select the optimal AV delay and VV interval in CRT.

Three‐Dimensional Echocardiographic Optimization Improves Outcome in Cardiac Resynchronization Therapy Compared to ECG Optimization: A Randomized Comparison

“…In a recent study, Sonne et al were able to demonstrate that the elaborate 3DE optimization protocol acutely improved LV systolic function and decreased dyssynchrony and ESV compared with empiric programming of biventricular pacemakers . Nevertheless, it was unclear if these acute changes in LV function would translate into robust changes later on in the course.…”

“…One limitation of 3DE assessment of LV dyssynchrony is the dependency on image quality for accurate tracking of the endocardial boundary in all 16 segments, because inadequate tracking in one segment can affect the calculated left ventricular dyssynchrony index . Thus, to avoid the issue of low signal‐to‐noise ratio in several segments in our study, six (8%) patients were excluded because of poor image quality.…”

“…There are scarce studies that evaluated the effect of a combined approach of AV‐delay and VV‐interval optimization . In a pilot study, it was shown that a novel echocardiographic optimization protocol with a combination of Doppler echocardiography (DE) and three‐dimensional echocardiography (3DE) for AV‐ and VV‐interval optimization resulted in acutely improved ejection fraction (EF), decreased dyssynchrony, and end‐systolic volume (ESV) compared with empiric programming of biventricular pacemakers . The positive acute results are especially encouraging as LV resynchronization acutely, after implantation of biventricular pacemakers, predicts response to CRT in the long term .…”

Cardiac resynchronization therapy - A comparison of VV delay optimization by 3D echocardiography using systolic dyssynchrony index and QRS width assessment at 6 months after CRT implantation

“…Stejným způsobem bylo nastavení mezikomorového zpoždění provedeno ve dvou studiích autorů Sonne a spol. Autoři pozorovali větší redukci dyssynchronie LK, end-systolického objemu levé komory; (LVESV) a zlepšení její ejekční frakce (EF) akutně (oproti simultánní stimulaci) a v odstupu tří měsíců od implantace SRL (ve srovnání s nastavením mezikomorového zpoždění dle šíře komplexu QRS) [14,15]. Ve studii autorů Nitsche a spol.…”

“…Rozvoj 3DE přináší nové možnosti hodnocení kinetiky srdečních oddílů a nové přístupy k optimalizaci SRL, jak ukazují i slibné výsledky některých studií [14][15][16]. K nastavení mezikomorového zpoždění jsme použili SDI, který přináší přesnější hodnocení globální mechanické dyssynchronie LK (ve srovnání s dvojrozměrnou TDI), bez úhlové závislosti a s rozumnou intra-a interobservační variabilitou [11].…”