Influence of external stenting on venous graft flow parameters in coronary artery bypass grafting: A randomized study

Abstract

OBJECTIVES Long-term patency of saphenous vein grafts (SVGs) remains a concern after coronary artery bypass grafting. Interventions to overcome this problem include monitoring intraoperative flow profile and, more recently, external stenting of SVGs. It is not known to what extent external stenting changes the perioperative flow characteristics of SVGs. The aim of this study was to assess whether the presence of an external stent affects perioperative graft flow parameters as evaluated by transit time flowmetry. METHODS Thirty-five patients were included from 1 centre participating in a multicentre, randomized clinical trial of external stenting of SVGs. Patients were eligible if scheduled for on-pump multivessel coronary artery bypass grafting including planned SVGs to both the right and the left coronary territories. Each patient received external stenting of a single SVG randomly allocated intraoperatively to either coronary territory. The primary end-points were mean graft flow, pulsatility index, percentage of diastolic filling and percentage of backward flow in stented versus non-stented SVGs. RESULTS External stenting was performed in 17 SVGs supplying the left territory (20 non-stented SVGs for control) and in 18 SVGs supplying the right territory (18 non-stented SVGs for control). No significant difference was found in flow parameters between stented and non-stented SVGs in the overall group or between pre-defined groups of SVGs supplying the right and left territories, respectively. CONCLUSIONS External stenting of SVGs do not affect intraoperative flow parameters significantly. CLINICAL TRIAL REGISTRATION clinicaltrials.gov identifier: NCT02511834.