Effect of a standardized meal on the threshold of exercise-induced myocardial ischemia in patients with stable angina.
OBJECTIVE
This study was undertaken to determine the effect of a standardized meal on the ischemic threshold and exercise capacity in a series of 20 patients with stable angina, exercise-induced ischemia and reversible exercise-induced perfusion defects.


BACKGROUND
It is generally accepted that exercise tolerance in patients with angina is reduced after a meal. However, studies that have addressed this phenomenon have yielded results that are contradictory and inconclusive.


METHODS
Two exercise tests using the Bruce protocol with technetium-99m (99mTc)-sestamibi were performed on consecutive days in a randomized order. One test was performed in the fasting state and the other 30 min after a 1,000-calorie meal.


RESULTS
In the postprandial state, exercise time to ischemia was reduced by 20% from 248 +/- 93 s to 197 +/- 87 s (p = 0.0007), time to angina by 15% from 340 +/- 82 s to 287 +/- 94 s (p = 0.002) and exercise tolerance by 9% from 376 +/- 65 s to 344 +/- 86 s (p = 0.002). Rate-pressure products at these exercise test end points were not significantly different in the fasting and postprandial tests, and the quantitative 99mTc-sestamibi ischemia score was unchanged.


CONCLUSIONS
In patients with stable angina, a 1,000-calorie meal significantly reduced time to ischemia, time to angina and exercise tolerance because of a more rapid increase in myocardial oxygen demand with exercise. The extent and severity of exercise-induced ischemia were unchanged.
Colles
P
P
Department of Medicine, Montreal Heart Institute, Quebec, Canada.
Juneau
M
M
Grégoire
J
J
Larivée
L
L
Desideri
A
A
Waters
D
D
D000368:Aged; D000787:Angina Pectoris / Q000503:physiopathology*; D004562:Electrocardiography; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D005502:Food; D006321:Heart / Q000000981:diagnostic imaging; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging / Q000503:physiopathology*; D009206:Myocardium / Q000378:metabolism; D010101:Oxygen Consumption; D011446:Prospective Studies; D015899:Tomography, Emission-Computed, Single-Photon