Comparison of Stress Perfusion MRI and SPECT for Detection of Myocardial Ischemia in Patients With Angiographically Proven Three-Vessel Coronary Artery Disease

OBJECTIVE. This study aims to evaluate the diagnostic value of stress perfusion MRI and SPECT for the detection of myocardial ischemia in patients with angiographically proven three-vessel coronary artery disease. MATERIALS AND METHODS. We retrospectively enrolled 78 patients with angiographically proven three-vessel coronary artery disease who underwent both stress perfusion MRI and SPECT within 4 weeks of each other. Image analysis was performed to compare the diagnostic value of stress perfusion MRI with that of SPECT; coronary angiography was used as the reference standard. The statistical significance of the difference between stress perfusion MRI and SPECT was evaluated by use of the paired McNemar test. RESULTS. Myocardial ischemia was detected significantly more often by stress perfusion MRI than by SPECT, with more abnormal segments (mean +/- SD, 10.1 +/- 3.6 vs 4.9 +/- 2.6; p < 0.001) and abnormal vascular territories (2.55 +/- 0.5 vs 1.64 +/- 0.7; p < 0.001) identified per patient. The overall sensitivity for identifying perfusion defects in three vascular territories was higher for stress perfusion MRI than for SPECT (84.6% vs 55.1%; p < 0.001). The sensitivity of stress perfusion MRI and SPECT for detecting any perfusion defect per patient was 100% and 96.2%, respectively. However, perfusion defects in all three vascular territories were detected in 57.7% of patients by stress perfusion MRI but in only 11.5% of patients by SPECT. CONCLUSION. Stress perfusion MRI is superior to SPECT for detecting myocardial ischemia in patients with angiographically proven three-vessel coronary artery disease.