Medical therapy vs early revascularization in diabetics with chronic total occlusions: A meta-analysis and systematic review

BACKGROUND Management of chronic total occlusions (CTO) in diabetics is challenging, with a recent trend towards early revascularization [ER: Percutaneous coronary intervention (PCI) and bypass grafting] instead of optimal medical therapy (OMT). We hypothesize that ER improves morbidity and mortality outcomes in diabetic patients with CTOs as compared to OMT. AIM To determine the long term clinical outcomes and to compare morbidity and mortality between OMT and ER in diabetic patients with CTOs. METHODS Potentially relevant published clinical trials were identified in Medline, Embase, chemical abstracts and Biosis (from start of the databases till date) and pooled hazard ratios (HR) computed using a random effects model, with significant P value < 0.05. Primary outcome of interest was all-cause death. Secondary outcomes included cardiac death, prompt revascularization (ER) or repeat myocardial infarction (MI). Due to scarcity of data, both Randomized control trials and observational studies were included. 4 eligible articles, containing 2248 patients were identified (1252 in OMT and 1196 in ER). Mean follow-up was 45-60 mo. RESULTS OMT was associated with a higher all-cause mortality [HR: 1.70, 95% confidence interval (CI): 0.80-3.26, P = 0.11] and cardiac mortality (HR: 1.68, 95%CI: 0.96-2.96, P = 0.07). Results were close to significance. The risk of repeat MI was almost the same in both groups (HR: 0.97, 95%CI: 0.61-1.54, P = 0.90). Similarly, patients assigned to OMT had a higher risk of repeat revascularization (HR: 1.62, 95%CI: 1.36-1.94, P < 0.00001). Sub-group analysis of OMT vs PCI demonstrated higher all-cause (HR: 1.98, 95%CI: 1.36-2.87, P = 0.0003) and cardiac mortality (HR: 1.87, 95%CI: 0.96-3.62, P = 0.06) in the OMT group. The risk of repeat MI was low in the OMT group vs PCI (HR: 0.53, 95%CI: 0.31-0.91, P = 0.02). Data on repeat revascularization revealed no difference between the two (HR: 1.00, 95%CI: 0.52-1.93, P = 1.00). CONCLUSION In diabetic patients with CTO, there was a trend for improved outcomes with ER regarding all-cause and cardiac death as compared to OMT. These findings were reinforced with statistical significance on subgroup analysis of OMT vs PCI.