Interaction effect of myocardial infarction and obesity on left atrial functions

Effects of obesity on left atrial phasic functions in patients with chronic ischemic heart disease and preserved left ventricular ejection fraction without recent myocardial infarction: a two-dimensional speckle-tracking echocardiography study

PURPOSE

Left atrial (LA) phasic functions in various subgroups of subjects with obesity are differently impaired, suggesting that obesity may have diverse effects in dissimilar subgroups of subjects with obesity. We aimed to compare the effects of obesity on LA phasic functions in patients suffering from chronic ischemic heart disease with a preserved left ventricular ejection fraction and without a recent myocardial infarction.

METHODS

In our cross-sectional study, 145 consecutive candidates for isolated coronary artery bypass graft (CABG) surgery were divided according to the presence of obesity into 2 groups: obese (36 patients) and nonobese (103 patients), and LA phasic functions were evaluated by two-dimensional speckle-tracking echocardiography (2D STE).

RESULTS

The longitudinal strain rate during the reservoir phase (3.0 ± 0.7 s-1 vs 2.7 ± 0.6 s-1; P = 0.032), longitudinal strain during the contraction phase (19.2 ± 4.7% vs 17.2 ± 4.1%; P = 0.022), and the longitudinal strain rate during the contraction phase (4.4 ± 1.2 s-1 vs 3.9 ± 1.2 s-1; P = 0.036) decreased in the obese group compared with the nonobese group. The other longitudinal 2D STE-derived markers of the LA phasic functions were not different between the 2 groups.

CONCLUSIONS

Among patients suffering from chronic ischemic heart disease with a preserved left ventricular ejection fraction and without a recent myocardial infarction, LA reservoir and contraction functions as measured by 2D STE were impaired in patients with obesity compared with those without it.