CARDIAC IMAGING FOR RISK STRATIFICATION WITH DOBUTAMINE-ATROPINE STRESS-TESTING IN PATIENTS WITH CHEST PAIN - ECHOCARDIOGRAPHY, PERFUSION SCINTIGRAPHY, OR BOTH

Background Pharmacological stress echocardiography and myocardial perf usion scintigraphy are used frequently for risk stratification in pati ents with suspected myocardial ischemia. However, their relative progn ostic strength has never been explored. Methods and Results Two hundre d twenty consecutive patients with chest pain (mean age, 60+/-12 years ; 124 men, 115 with previous myocardial infarction) were studied with dobu tamine-atropine stress echocardiography (ECHO) and simultaneous T e-99m sestamibi single photon emission computed tomography imaging (MI BI). Ischemia was defined as deterioration in left ventricular wall mo tion and reversible perfusion defects, respectively. ECHO was positive for ischemia in 76 and MIBI in 91 patients (agreement, 77%; kappa=.51 ). During follow-up of 31+/-15 months, 24 patients had hard cardiac ev ents (nonfatal myocardial infarction or cardiac death). By univariate analysis, age, history of congestive heart failure, and any abnormalit y or ischemia on ECHO or MIBI were associated with cardiac events. Mul tivariate analysis revealed that age, abnormal ECHO (odds ratio [OR], 18.9; 95% CI, 2.5 to 146.0) or MIBI (OR, 12.8; 95% CI, 1.7 to 98.3), a nd ischemia on ECHO (OR, 4.0; 95% CI, 1.6 to 9.9) or MIBI (OR, 3.0; 95 % CI, 1.2 to 7.4) had independent predictive values. When ECHO was use d as a first option, the addition of MIBI to all nonischemic ECHO stud ies decreased the OR from 4.0 (95% CI, 1.6 to 9.9) to 3.8 (95% CI, 1.4 to 10.2). Addition of MIBI confined to nonischemic ECHO studies in wh ich target heart rate was not attained (nondiagnostic studies) increas ed the OR to a maximal 5.7 (95% CI, 2.2 to 15.0). In contrast, the add ition of ECHO to nondiagnostic MIBI studies was not useful. Conclusion s Dobutamine-atropine ECHO and MIBI provide comparable prognostic info rmation. The addition of MIBI to ECHO may be useful in patients with n ondiagnostic ECHO studies.