It has been well recognized that exercise tolerance and angina threshold in patients with coronary artery disease (CAD) are reduced after a meal. But precise mechanism leading to the postprandial worsening of angina has yet to be adequately defined. This study was undertaken to determine the effect of a mixed meal on cardiac performance and heart rate variability (HRV) in patients with CAD.

24 patients with angina or myocardial infarction were studied. Echocardiographic examination and heart rate variability test were performed in the fasting state and the other 40-60 minutes after a 600-800 kcal mixed meal.

In the postprandial state, resting heart rate was significantly increased by 5.2% from 64.8±10.69 beats/min to 68.2±10.2 beats/min (p<0.01), stroke volume by 8.1% from 59.6±17.3 ml to 64.4±18.1 ml (p<0.01), cardiac output by 14.2% from 3.8±1.06 to 4.3±1.21 (p<0.01). E wave and A wave of mitral filling flow and E/A ratio were not significantly different in the fasting and postprandial tests. But DT and IVRT were significantly increased in the postprandial state (p<0.05, p<0.01 respectively). HRV was not different in the fasting and postprandial state.

In patients with CAD, a 600-800 kcal mixed meal significantly increased resting heart rate, stroke volume, cardiac output, DT and IVRT.