Radial access in patients with acute coronary syndrome without persistent ST-segment elevation: Systematic review, collaborative meta-analysis, and meta-regression

Background Consistent evidence of benefit exists for radial access (RA) in ST-elevation acute myocardial infarction (STEMI). Patients with non ST-elevation acute coronary syndrome (NSTE-ACS) have a more varied ischemic and bleeding profile. No randomized trial of vascular access ever focused on NSTE-ACS and landmark studies did not provide conclusive results in this heterogeneous subset of patients. Methods We assessed in a meta-analysis whether RA is associated with improved outcomes in NSTE-ACS patients. Included studies had to meet the following criteria: 1) enrolling patients with NSTE-ACS undergoing invasive management; 2) reporting outcomes with respect to RA as compared with femoral access (FA); 3) reporting short-term (procedural, in-hospital and up to 30-day) or long-term clinical outcomes. Studies were pooled with fixed and random effects models and heterogeneity was investigated by weighted meta-regression. Results Eleven studies were included encompassing 131.339 patients, 46.451 receiving RA and 84.888 receiving FA. Thirty-day mortality and MACE were lower with RA (p < 0.001 with fixed effects, p = NS with random effects model), but these results depended on one large observational database. Major bleeding was consistently reduced by RA (p < 0.001), albeit an inverse relationship with the proportion of patients in each study receiving FA and experiencing major bleeding was evident. The association of RA with reduced long-term mortality was of borderline significance (p = 0.054 with random-effects, p = 0.001 with fixed-effect model) and also depended on major bleeding in FA patients. Conclusions RA is associated with better outcomes as compared with FA in NSTE-ACS, although this observation is influenced by nonrandomized comparisons. Large heterogeneity exists among studies. Registration This study is registered in the PROSPERO database (CRD42015029459).