Multiple vs single arterial grafting in coronary surgery among diabetic patients: a meta-analysis

Abstract Background and aim The use of more than one arterial conduit in coronary surgery has been widely associated with better long-term results. We sought to investigate the benefits of Multiple Arterial Grafts (MAG) over Single Arterial Grafts (SAG), among diabetic patients, in short and long-term results throughout a meta-analysis of propensity score matching (PSM) studies. Methods MEDLINE and ISI Web of Science were used to find relevant literature (1960–2018). We included cohort studies with at least 200 patients and that reported one of these outcomes: long-term survival, early mortality or sternal wound infection (SWI). Survival was collected through hazard ratio (HR) along with their variance and the other endpoints using frequencies or odds ratio (OR) from the matched sample. Fixed effect models were used to compute statistical combined measures and 95% confidence intervals (CI). Results Eleven studies were included performing a total of 9670 diabetic patients: 4833 MAG and 4837 SAG (1:1 PSM in all studies). MAG group consisted in bilateral internal mammary artery (BIMA) in 8 studies; single IMA (SIMA)+radial artery (RA) in 5 studies; and one study reported several MAG approaches: BIMA+RA+Gastroepiploic artery (GEA), SIMA+RA+GEA, SIMA+GEA or BIMA+GEA. SAG group consisted in SIMA with or without saphenous vein graft in all studies, except for one that included also patients with GEA instead of SIMA. Ten studies reported long-term survival and mean follow-up time ranged from 5 to 12 years (max. follow-up 30y). Overall, MAG had significantly improved long-term survival compared with SAG (pooled HR=0.79, 95% CI: 0.74–0.85, p<0.01). In-hospital mortality was reported by 6 studies (4202 patients: 2099 MAG and 2103 SAG) and occurred in 3.0% vs. 3.3% in MAG vs. SAG patients, respectively (pooled OR: 0.91, 95% CI: 0.65–1.29, p=0.60). SWI was reported by 6 studies (4432 patients: 2216 MAG and 2216 SAG) and occurred in 2.8% vs. 2.2% in MAG vs. SAG patients, respectively (pooled OR: 1.31, 95% CI: 0.90–1.92, p=0.15). Excluding one article in which MAG group consisted in IMA+RA, the remaining 5 BIMA vs. SIMA studies reported an higher risk of SWI in MAG group (pooled OR: 1.63, 95% CI: 1.07–2.49, p=0.02) Conclusion Considering PSM studies, MAG provides superior long-term survival compared to SAG in diabetic patients. This surgical technique does not implement additional risk regarding in-hospital mortality, but MAG with BIMA was associated with a higher risk of SWI in this specific subgroup of patients. Forest plot survival Funding Acknowledgement Type of funding source: Public grant(s) – EU funding. Main funding source(s): Universidade do Porto/FMUP e FSE-Fundo Social Europeu, NORTE 2020-Programa Operacional Regional do Norte,-Programas Doutorais