title: 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.
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, University of Louisville, Kentucky.
authors.forename: Abdur R
authors.initials: AR
authors.lastname: Khan
authors.affiliation: Division of Cardiovascular Medicine, Mercy St Vincent Medical Center, Toledo, Ohio.
authors.forename: Faraz
authors.initials: F
authors.lastname: Khan Luni
authors.affiliation: Department of Cardiology, Mount Sinai St. Luke's & Roosevelt Hospitals, New York, New York.
authors.forename: Chirag
authors.initials: C
authors.lastname: Bavishi
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, University of Toledo Medical Center, Toledo, Ohio.
authors.forename: Sobia
authors.initials: S
authors.lastname: Khan
authors.affiliation: Division of Cardiovascular Medicine, Department of Internal Medicine, University of Toledo Medical Center, Toledo, Ohio.
authors.forename: Ehab A
authors.initials: EA
authors.lastname: Eltahawy
mesh_terms: D054058:Acute Coronary Syndrome / Q000175:diagnosis / Q000401:mortality* / Q000503:physiopathology* / Q000628:therapy; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D003326:Coronary Circulation; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D064887:Observational Studies as Topic; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011379:Prognosis; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors
keywords: acute coronary syndrome; coronary dominance; left dominant circulation; meta-analysis; mortality; right dominant circulation