COMPARATIVE-EVALUATION OF DOPAMINE INFUSION AND TREADMILL EXERCISE TESTS IN THE DIAGNOSIS OF CORONARY-ARTERY DISEASE

Dopamine infusion test (DIT) was compared with treadmill exercise test (TMT) in 20 patients of chronic stable angina (TMT +ve) for inducing reversible myocardial ischaemia so as to assess its efficacy as an alt ernative to TMT in patients who cannot perform exercise test due to ce rtain non-cardiac diseases. DIT was positive in 15 of the 20 patients studied; rive patients in whom DIT was negative had late onset, early offset changes in TMT. Haemodynamically the increase in heart rate (HR ) was less but rise in systolic blood pressure (SBP) was more with dop amine infusion in comparison to the corresponding stage of TMT. Howeve r, evidence of myocardial ischaemia (ST segment depression) appeared a t a lower rate pressure product (RPP) with dopamine infusion compared to exercise test. The test was tolerated well, in higher doses (stages III & IV) side effects like ventricular ectopic beats, palpitation an d angina not warranting stoppage of test, were seen in some patients. Dopamine infusion is a good chemical stress test, and can be used as a n alternative to TMT especially in situations where the latter cannot be performed. The test is simple, cost effective, non-invasive and wel l tolerated.