Comparison of cardiovascular response to combined static-dynamic effort, postprandial dynamic effort and dynamic effort alone in patients with chronic ischemic heart disease.

Abstract

SUMMARY The cardiovascular responses to combined static-dynamic effort, postprandial dynamic effort and dynamic effort alone were evaluated by upright bicycle ergometry during equilibrium-gated blood pool scintigraphy in 24 men, mean age 59 ± 8 years, with chronic ischemic heart disease. Combined static-dynamic effort and the postprandial state elicited a peak cardiovascular response similar to that of dynamic effort alone: work load 643 ± 156 and 638 ± 161 vs 650 i 153 kg-m/min, respectively; heart rate 147 ± 14 and 145 ± 14 vs 143 ± 17 beats/min; systolic pressure 195 i 26 and 200 ± 25 vs 197 ± 25 mm Hg; and rate-pressure product 286 ± 48 and 292 ± 55 vs 282 ± 52. Heart rate, intraarterial systolic and diastolic pressures, ratepressure product and ejection fraction were similar for the three test conditions at the onset of ischemia and at peak effort. The prevalence and extent of exercise-induced ischemic left ventricular dysfunction, ST-segment depression, angina pectoris and ventricular ectopic activity were also similar during the three test conditions. Direct and indirect measurements of systolic and diastolic blood pressure were highly correlated. The onset of ischemic ST-segment depression and angina pectoris correlated as strongly with heart rate alone as with the rate-pressure product during all three test conditions. The cardiovascular response to combined static-dynamic effort and to postprandial dynamic effort becomes more similar to that of dynamic effort alone as dynamic effort reaches a symptom limit. If significant ischemic and arrhythmic abnormalities are absent during symptom-limited dynamic exercise testing, they are unlikely to appear during combined static-dynamic or postprandial dynamic effort. This simplifies the task of formulating guidelines for physical effort in patients with chronic ischemic heart disease, especially in providing "clearance" to perform avocational and vocational tasks involving combined static-dynamic and postprandial dynamic effort.EXERCISE TESTING for the detection of ischemic ST-segment depression or angina pectoris is usually performed in the fasting state, with care to avoid the static effort involved in gripping of handrails or of handlebars. Although such testing accurately reflects the cardiovascular response to isolated dynamic effort, it does not simulate the superimposition of static on dynamic effort or of dynamic effort in the postprandial state -circumstances to which patients with ischemic heart disease are exposed during their customary activities.Patients with ischemic heart disease are usually advised to avoid dynamic activities in which there is a significant static component, but we' and others2' 3 have noted a lower incidence of exercise-induced ischemic ST-segment depression or angina pectoris when patients performed combined static-dynamic effort than when they performed dynamic effort alone. Haissly et al.2 measured a higher diastolic blood pressure during combined static-dynamic effort than during dynamic effort alone and attributed the lower...

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