Efficacy comparison of mid-term patency rates between sequential and individual saphenous vein grafts after off-pump coronary artery bypass grafting

Objective To compare the mid-term patency rates between individual and sequential saphenous vein grafts after off-pump coronary artery bypass grafting (OPCAB) and evaluate the effect of sequential anastomosis technique on the graft patency after OPCAB. Methods Clinical data of 200 patients receiving OPCAB with individual and sequential saphenous vein grafts from June 2011 to June 2013 were retrospectively analyzed. The multislice spiral CT angiography (MSCTA) was performed at an average of (20.0±21.5) months after OPCAB. The patency rate of individual and sequential grafts and anastomoses were compared, and the effect of different locations on the patency rate of the anastomoses was analyzed. Results There was no significant difference in the patency rate between individual and sequential grafts (χ2=1.886, P=0.170). The anastomosis patency rates in different locations had no significant differences between individual and sequential grafts (χ2=4.567, P=0.102). There was no significant difference in the distal anastomosis patency rate between sequential and individual grafts (P>0.05). The anastomosis patency rate in sequential graft had no significant difference in the side-to-side anastomose versus end-to-side anastomose (P>0.05). The patency rate of side-to-side anastomose in the sequential graft was higher than that of distal anastomose in individual graft (χ2=4.653, P=0.031). There were no significant differences in the patency rate in sequential grafts among different coronary systems (including the anterior descending branch, the right coronary artery and the circumflex branch) and individual grafts among different coronary systems respectively (all P>0.05). The anastomosis patency rates had no difference between sequential and individual grafts in the anterior descending branch. There were significant difference in end-to-side anastomosis patency rates between sequential and individual grafts in different coronary systems (χ2=6.184, P=0.045), but the distal anastomosis patency rate had no difference (χ2=1.807, P=0.431). No significant difference in the patency rates between sequential and individual grafts in side-to-side versus end-to-side (all P>0.05). Conclusions There is no significant difference in the mid-term patency rate between individual and sequential saphenous vein grafts after off-pump coronary artery bypass grafting (OPCAB). The patency rate is related with the anastomotic mode, the location of anastomotic, and the quality of the target vessel, diameter, number of grafts and other factors. The mid-term patency rate can be improved by choosing the target vessel with better conditions as the most distal sequential bridge, when conducting sequential anastomosis technique. Key words: Coronary artery bypass grafting, off-pump; Saphenous vein; Surgical stomas