SAFETY AND FEASIBILITY OF DOBUTAMINE-ATROPINE STRESS-TESTING IN HYPERTENSIVE PATIENTS

Dobutamine stress testing is increasingly used for the diagnosis and f unctional evaluation of coronary artery disease. The aim of this study was to assess the hemodynamic profile, safety, and feasibility of dob utamine stress testing in hypertensive patients. Dobutamine (up to 40 mu g/kg per minute)-atropine (up to 1 mg) stress echocardiography was performed for the detection of myocardial ischemia in 1164 patients wi th limited exercise capacity (age, 60 +/- 12 years; 761 men); 446 pati ents were known to have hypertension. The test was considered feasible when 85% of the maximal heart rate and/or an ischemic end point (new or worsened wall motion abnormalities, ST segment depression, or angin a) was achieved. No myocardial infarction or death occurred during the test. Dobutamine induced a significant increase of heart rate in pati ents with and without hypertension (59 +/- 25 and 63 +/- 23 beats per minute, respectively). Peak rate pressure product was similar in patie nts with and without hypertension (18566 +/- 4584 and 18230 +/- 4508). Hypotension (systolic pressure drop >40 mm Hg) during the test was mo re frequent in hypertensive patients (7% versus 4% in normotensive, P< .05). Independent predictors of hypotension were baseline systolic pre ssure greater than 140 mm Hg (odds ratio, 6.9; 95% confidence interval , 3.4 to 14), older age (odds ratio, 1.04; 95% confidence interval, 1. 01 to 1.07), and medication with calcium channel blockers (odds ratio, 1.8; 95% confidence interval, 1.1 to 3.5). The prevalence of ventricu lar tachycardia was similar (4.1%) in both groups. Episodes of 10 beat s or more (0.06% of patients) were terminated promptly by intravenous metoprolol administration. Dobutamine stress testing was considered fe asible in 91% of patients with and 92% of patients without hypertensio n. Dobutamine-atropine stress echocardiography is a safe and feasible method for the assessment of hypertensive patients referred for evalua tion of myocardial ischemia. Despite the higher prevalence of dobutami ne-induced hypotension in these patients, the feasibility of the test is comparable to that in individuals without hypertension.