The main trunk of RCA may be the best choice of sequential vein graft distal end-to-side anastomosis

Abstract

Objective: The purpose of this study was to investigate the effect of different anastomotic positions on the early patency of the distal end-to-side anastomosis of sequential saphenous vein grafts (SVG) in off-pump coronary artery bypass grafting (OPCAB).

Methods: A total of 259 patients who underwent OPCAB between August 2014 and August 2019 and presented for coronary computed tomography angiography (CCTA) to evaluate graft patency at 1 year post-OPCAB were analyzed. There are two kinds of distal end-to-side anastomosis of SVG, to posterior descending artery (PDA) and main trunk of right coronary artery (RCA). In all, 1044 distal coronary anastomoses on 518 grafts which included 180 left internal mammary artery (LIMA) grafts, individual 79 SVG and 259 sequential SVG were assessed using CCTA. The blood flow (BF), pulsatility index (PI), and patency of every anastomosis were recorded. Besides, comprehensive data of SV-PDA and SV-RCA patients was also compared.

Results: The mean BF of SV-RCA was significantly higher than that of SV-PDA (31.71 ± 18.60 vs 22.62 ± 14.48, p = 0.001), and the PI value of SV-RCA was significantly lower than that of SV-PDA (2.57 ± 1.17 vs 3.50 ± 1.69, p = 0.001). The patency of RCA system was significantly lower than that of the LAD and the left circumflex system (79.25% vs 90.13%, 90.23% respectively, p = 0.001). In sequential SVG, the patency of SV-PDA was significantly lower than that of SV-RCA (74.01% vs 86.59%, p = 0.001). Although, there was no significant difference in left ventricular ejective fraction, the left ventricular end-diastolic diameter (LVDd) in SV-PDA group was significantly larger than that in SV-RCA (52.67 ± 8.72 mm vs 47.34 ± 7.55, p = 0.001). In addition, the target vessel diameter in SV-PDA group was smaller than that in SV-RCA group (1.52 ± 0.41 mm vs 3.17 ± 0.88 mm, p = 0.001).

Conclusion: The early patency of sequential SVG end to RCA after OPCAB is generally superior to that of to PDA, especially for patients with large LVDd.

Keywords: distal anastomosis; early patency; off-pump coronary artery bypass grafting; saphenous vein graft.