Left dominant circulation increases mortality in acute coronary syndrome: A systematic review and meta-analysis of observational studies involving 255,718 patients.

ABSTRACT

BACKGROUND: The effect of coronary dominance on mortality in patients with acute coronary syndrome (ACS) remains unclear. We performed a meta-analysis to evaluate the effect of coronary dominance in patients with ACS. METHODS: Several data sources were searched for studies which compared studies that compared outcomes between right and left dominant coronary circulation in patients with ACS. The measured outcomes were in-hospital, 30-day or long-term mortality as reported in individual studies. The Generic inverse variance method was used in a random-effects model to pool mortality as an outcome. Odds ratio (OR) was calculated for mortality in the left dominant circulation relative to a right dominant one. Sub-group analysis was performed after stratification of mortality by duration. RESULTS: A total of 5 studies with 8 comparisons and 255,718 participants revealed an increased risk mortality (OR = 1.27 (95% CI 1.13 - 1.42; P < 0.0001; I(2) = 34%). Sub-group analysis revealed that the increased risk was evident at all time periods after the ACS; in-hospital (OR = 1.37; 95% CI 1.07 - 1.76; P = 0.01; I(2) = 50%), at 30 days (OR = 1.69; 95% CI 1.14 - 2.52; P = 0.009; I(2) = 18%) and long-term (OR = 1.15; 95% CI 1.03 - 1.28; P = 0.01; I(2) = 0%). CONCLUSIONS: In this meta-analysis we found that there is an increased risk of mortality with LD coronary circulation in patients with ACS. The knowledge of coronary dominance may not only be helpful as an incremental prognostic factor beyond pre-procedural risk scores in all patients with ACS, but may also aid in clinical decision making in a subset of these patients. © 2015 Wiley Periodicals, Inc.