Transient Ischemic Dilatation Ratio in Stress Myocardial Perfusion SPECT in Diabetic Patients-A Systematic Review and Meta-Analysis

Abnormal values of the transient ischemic dilation (TID) ratio are associated with severe and extensive coronary artery disease (CAD). TID can be used as a diagnostic and prognostic marker of CAD in diabetic patients. The aim of current study was to determine the pooled estimate of TID ratio in single myocardial perfusion scan in diabetic patients by a systematic review and meta-analysis. The electronic databases of PubMed/MEDLINE, Scopus (EMBASE), Web of Science, and Cochrane Library up to December 30, 2013 were searched. The reference lists of all included studies were searched for further studies. The search strategy was according to PICO characteristics. The heterogeneity between the studies was accounted with P<0.1. The random/fixed effect model was used according to the heterogeneity. Point estimates were pooled estimate of TID ratio with 95% confidence interval (CI) by pooling available data. Egger’s test was used to assess publication bias. The primary search contained 423 studies. Totally, 17 studies met the inclusion criteria and the critical appraisal scores. The TID ratio in four single pharmacological stress studies with angiographic evidence of low risk or normal coronary artery disease was 1.079 (95% CI: 1.07-1.089). Our findings were achieved according to the purpose of the study and the pooled estimate of TID±SD was calculated. The pooled estimate of TID was so smaller than the TID calculated in individual studies and so precise.