Evaluation of left ventricular mechanical dyssynchrony in patients with heart failure after myocardial infarction by real-time three-dimensional echocardiography.

OBJECTIVES: To evaluate the incidence and prevalence of left ventricular (LV) dyssynchrony in patients with heart failure after myocardial infarction (MI) by real- time three-dimensional echocardiography (RT-3DE), and to investigate the clinical application value of using RT-3DE as a method of providing more detailed information for clinical strategy.

METHODS: This cross-sectional study was carried out in Renmin Hospital of WuHan University, Hubei Province, China from July 2009 to December 2010. The RT-3DE was performed on 43 patients with chronic heart failure after MI and 30 normal subjects, to analyze LV volume and left ventricular ejection fraction (LVEF), also the LV systolic dyssynchrony index (SDI).

RESULTS: The dyssynchrony rate of the total MI patients was 83.7%, and was 100% in the severe dysfunction group. The SDI of MI patients was significantly higher than the control subjects (p less than 0.01), and the SDI of those whose LVEF </=35% is obviously higher than the patients whose LVEF ranges from 35-50%. The LVEF was well correlated with SDI (r = -0.84, p less than 0.001) in MI patients. The LV dyssynchrony prevalence was more severe in the anterior MI than the inferior MI.

CONCLUSIONS: The LV dyssynchrony occurred more often in patients with cardiac dysfunction after MI, and was well related with the LV systolic function. The RT-3DE could be considered as an effective and informative tool for the evaluation of LV dyssynchrony.