Real-time three-dimensional echocardiography as a novel approach to quantify left ventricular dyssynchrony: a comparison study with phase analysis of gated myocardial perfusion single photon emission computed tomography.

BACKGROUND

Different imaging modalities have been explored for assessment of left ventricular (LV) dyssynchrony. Gated myocardial perfusion single photon emission computed tomography (GMPS) with phase analysis is a reliable technique to quantify LV dyssynchrony and predict response to cardiac resynchronization therapy.

OBJECTIVE

Real-time 3-dimensional echocardiography (RT3DE) is a novel imaging technique that provides a LV systolic dyssynchrony index, based on regional volumetric changes as a function of time and calculated as the SD of time to minimum systolic volume of 16 standard myocardial segments expressed in percentage of cardiac cycle. The aim of this study was to compare LV dyssynchrony evaluated with GMPS with LV dyssynchrony assessed with RT3DE.

METHODS

The study population consisted of 40 patients with heart failure who underwent both GMPS and RT3DE.

RESULTS

Good correlations between LV dyssynchrony assessed with RT3DE and GMPS were demonstrated (r = 0.76 for histogram bandwidth, r = 0.80 for phase SD, P < .0001). Patients with substantial LV dyssynchrony on GMPS (defined as > or = 135 degrees for histogram bandwidth and > or = 43 degrees for phase SD) had significantly higher LV systolic dyssynchrony index than patients without substantial LV dyssynchrony.

CONCLUSIONS

The good correlations between LV dyssynchrony assessed with GMPS and with RT3DE provide further support for the use of RT3DE for reliable assessment of LV dyssynchrony.