SAFETY OF DOBUTAMINE-ATROPINE STRESS MYOCARDIAL PERFUSION SCINTIGRAPHY

Dobutamine stress testing is increasingly used for the diagnosis and f unctional evaluation of coronary artery disease. However, the relation ship between myocardial perfusion abnormalities and complications of t he test has not been studied. Methods: We studied the hemodynamic prof ile, safety and feasibility of dobutamine (up to 40 mu g/kg/min)-atrop ine (up to 1 mg) stress myocardial perfusion SPECT imaging (with (TI)- T-201, Tc-99m-MIBI or tetrofosmin) in a consecutive series of 1076 pat ients (age = 59 +/- 11 yr, 50% with previous myocardial infarction) re ferred for evaluation of myocardial ischemia Results: No infarction or death occurred during the test. The test was considered feasible (ach ievement of 85% of the target heart rate or an ischemic endpoint) in 1 005 patients (94%). Hypotension (systolic blood pressure drop greater than or equal to 40 mm Hg) occurred in 37 patients (3.4%), Independent predictors were higher baseline systolic blood pressure (p < 0.0001), number of ischemic segments (p < 0.05) and age (p < 0.05). Supraventr icular tachyarrhythmias occurred in 48 patients (4.4%), Independent pr edictors were fixed perfusion defect (infarction) score (p < 0.005) an d age (p < 0.05). Ventricular tachycardia occurred in 41 patients (3.8 %), Independent predictors were infarction score (p < 0.01) and male g ender (p < 0.05), All arrhythmias terminated spontaneously or after me toprolol adminstration, Conclusion: Dobutamine-atropine myocardial per fusion scintigraphy is a feasible method for the evaluation of coronar y artery disease with a safety profile and feasibility comparable to t hose reported for dobutamine stress echocardiography, Patients with mo re severe fixed perfusion abnormalities are at a higher risk of develo ping tachyarrhythmias during the test.