Role of deferred stenting in patients with ST elevation myocardial infarction treated with primary percutaneous coronary intervention: A systematic review and meta-analysis.

OBJECTIVES: We conducted a meta-analysis of studies comparing deferred stenting strategy versus the conventional approach with immediate stenting in patients with ST elevation myocardial infarction.

BACKGROUND: Deferring stent after mechanical flow restoration has been proposed as a strategy to reduce the risk of "no reflow" in patients with STEMI undergoing primary percutaneous coronary intervention (pPCI). Conflicting evidence is available currently, especially after the recent publication of three randomized clinical trials.

METHODS: Searches in electronic databases were performed. Comparisons between the two strategies were performed for both hard clinical endpoints (all cause-mortality, cardiovascular mortality, unplanned revascularization, myocardial infarction and readmission for heart failure) and surrogate angiographic endpoints (TIMI flow < 3 and myocardial blush grade (MBG) < 2).

RESULTS: Eight studies (three randomized and five non-randomized) were deemed eligible, accounting for a total of 2101 patients. No difference in terms of hard clinical endpoints was observed between deferred and immediate stenting (OR [95% CI]: 0.79 [0.54-1.15], for all-cause mortality; odds ratio (OR) [95% CI]: 0.79 [0.47-1.31] for cardiovascular mortality; OR [95% CI]: 0.95 [0.64-1.41] for myocardial infarction; OR [95% CI]: 1.37 [0.87-2.16], for unplanned revascularization and OR [95% CI]: 0.50 [0.21-1.17] for readmission for heart failure). Notably, the deferred stenting approach was associated with improved outcome of the surrogate angiographic endpoints (OR [95% CI]: 0.43 [0.18-0.99] of TIMI flow < 3 and OR [95% CI]: 0.25 [0.11-0.57] for MBG < 2.

CONCLUSIONS: A deferred stenting strategy could be a feasible alternative to the conventional approach with immediate stenting in "selected" STEMI patients undergoing pPCI.