Prognostic value of normal stress myocardial perfusion imaging in diabetic patients: a meta-analysis

The prognostic value of normal stress myocardial perfusion single-photon emission computed tomography (MPS) in patients with diabetes has only been evaluated in single-center studies of relatively limited sample size. We performed a meta-analysis of published studies, including diabetic patients with known or suspected coronary artery disease (CAD), to assess the predictive value for adverse cardiac ischemic events of normal stress MPS. Studies published between January 1990 and December 2013 were identified by database search. We included studies using stress MPS to evaluate diabetic patients with known or suspected CAD and providing data on clinical outcomes of non-fatal myocardial infarction or cardiac death with a follow-up time ≥12 months. A total of 14 studies were finally included, recruiting 13,493 patients. The negative predictive value (NPV) for non-fatal myocardial infarction and cardiac death of normal MPS was 94.92% (95% confidence interval 93.67-96.05), during a weighted mean follow-up of 36.24 months, resulting in estimated event rate after a negative test equal to 5.08% (95% confidence interval 3.95-6.33). The corresponding annualized event rate after a negative test was 1.60% (95% confidence interval 1.21-2.04). Stress MPS has a high NPV for adverse cardiac events in diabetic patients with known or suspected CAD leading to define a “relatively low-risk” patients category.