Background:
CT coronary angiography with vasodilator stress might be of great value in detecting both myocardial ischemia and morphological stenoses of the coronary arteries. Stress myocardial perfusion MRI has been shown to provide accurate assessment of presence and extent of myocardial ischemia in patients with coronary artery disease(CAD). The aim of this study was to determine the value of stress myocardial perfusion CT for the detection of myocardial ischemia by using stress perfusion MRI as a reference method.
Methods:
The study protocol was approved by the institutional review board and all participants gave written informed consent. Cardiac CT was performed in 12 patients with suspected CAD by using a 64-detector MDCT scanner. Beta-blocker was orally administered prior to CT study. During continuous injection of adenosine, contrast enhanced CT images of the heart were acquired with retrospectively gated helical CT protocol. Adenosine stress myocardial perfusion MRI was performed within 2 weeks from CT perfusion study in all patients. Stress myocardial perfusion MDCT and MR images were qualitatively assessed by two observers using a 16-segment model.
Results:
All patients completed stress CT study protocol without significant side-effect. Averaged heart rate was 62+/−10 beats/min in the baseline state and 74+/−14 beats/min during adenosine stress. Perfusion abnormality during stress was observed in 83 (43.2%) of 192 segments by MDCT and in 89 (46.4%) of 192 segments by MRI. On a vessel based analysis, stress CT and stress MRI findings are concordant in 30 (83.3%) of 36 territories. The sensitivity, specificity and accuracy of adenosine stress myocardial perfusion CT for the predicting abnormal perfusion on stress perfusion MRI was 84.6%, 80% and 83.3%, respectively.
Conclusion:
Adenosine stress myocardial perfusion CT can be successfully performed in patients with CAD. Excellent agreement between stress myocardial perfusion CT and MRI observed in this study indicates the value of stress CT approach for comprehensive assessment of morphology and functional significance of CAD.
Comparison of the cost-effectiveness of stress myocardial perfusion MRI and SPECT in patients with suspected coronary artery disease