Medium and long-term patency results of distal anastomosis connectors: a meta-analysis

Background: The difficulty of suturing perfect anastomoses in limited-access conditions prevents the transition of traditional coronary artery bypass grafting (CABG) to sternal-sparing approaches, even in the robotic era. Automated coronary anastomotic connector technologies may address these difficulties, but to date, none have achieved broad adoption. Besides versatility, ease-of-use and cost-effectiveness, the key performance parameter of such technology is anastomotic patency. In this meta-analysis, we aim to evaluate published connector devices by examining their patency outcomes in distal anastomoses. Methods: The literature was systematically searched for studies comparing the angiographic patency of connector constructed coronary anastomoses to handsewn (HS) connections in adult patients undergoing CABG. The primary outcome was anastomosis patency across early (<30 days), mid-term (30 days to 1 year) and long-term (>1 year) follow-up. Random-effects meta-analyses were employed to analyze and compare patency using pooled risk ratios (RR) with 95% confidence intervals (CI). Results: The search yielded 14 studies concerning eight connector devices. In 4,311 patients, a total of 4,328 anastomoses were constructed, 674 with connector devices and 3,654 with a HS technique. The pooled device patency over all timeframes was non-inferior to the HS technique (RR 0.90, 95% CI: 0.56-1.44). Technologies having a relatively large blood-exposed non-intimal surface area (BENIS, >15 mm2) performed acceptably when applied to large target vessels [>2.0-2.5 mm inner diameter (ID)]. A tiny anastomotic orifice area (AOA, < ca. 4 mm2) appeared to adversely affect results. Technologies realizing a generous AOA in combination with a limited BENIS showed superior results and applicability by performing well across the entire range of target coronary artery diameters (>1.0-1.5 mm ID). Conclusions: The overall results suggest that connectors yield at least non-inferior anastomosis patency outcomes compared to HS techniques in all observed timeframes. Optimizing device characteristics like BENIS and AOA appear fundamental for broad applicability.