Relation of body fat distribution to cardiac dysfunction in obesity

ABSTRACT

Systolic time intervals [STI] were measured in obese-other-wise healthy-females [n=30] to assess their cardiac function in comparison to normal subjects [n=10]. The effect of body fat distribution on cardiac function was also studied. Electromechanical systole [QS2] [2557.6 +/- 2.9 V.S. 576.47 +/- 65 msec] and left ventricular ejection time [LVET] [411.86 +/- 3.3 v.S. 445.7 +/- 3.9 msec] were significantly shortened [P<0.01] and prejection period [PEP] [147.59 +/- 3.1 v.S. 131.2 +/- 2 .5 msec] was significantly prolonged [P<0.1] in obese subjects compared to controls respectively. PEP/LVET was significantly increased in obese [0.4 +/- 0.01] compared to control subjects [0.29 +/- 0.1]; P<0.01. In addition body mass index [BMI] was significantly correlated to PEP/IVET [r=0.474; P>0.01] and to PEP [r=0.361; P>005]. PEP/LVET was significantly increased in lower body segment obesity [LBSO] [0.43+0.01] compared to upper body segment obesity [UBSO] [0.358+0.01]; P<0.01. PEP was significantly prolonged [155.5+2.9V.S. 137.4+2.9 msec] and LVET significantly shortened [404.4+4.2 VS. 423.9+4.8 msec] [P<0.01] in LBSO compared to UBSO respectively. furthermore, PEP/LVET was significantly negatively correlated to the brachial to femoral adipose muscle ratio. [r=0.46; P<0.05]. It can be concluded that obesity has direct effects on cardiac function which correlate with the degree of obesity. Cardiac performance is more affected in lower body segment obesity reflecting a distinct mechansim for obesity to affect heart other than through its metabolic alteration