Early and late effects of coronary artery bypass grafting on cardiac haemodynamics during daily physical activities in patients with coronary artery disease

This study investigated the early and late effects of coronary artery bypass grafting (CABG) on left ventricular (LV) function during different physical daily activities in patients with multivessel coronary artery disease (CAD). In ten patients with multivessel CAD, cardiac haemodynamics were assessed during a 6-min walk test and during stair climbing 8±2 days before (study 1) and 15±3 days (study 2) and 120±3 days (study 3) after CABG. LV function was monitored by an ambulatory radionuclide system. In study 1, the walk test induced a significant increase in relative end-diastolic volume (EDV) and end-systolic volume (ESV) and no change in LV ejection fraction as compared to rest. In both study 2 and study 3, EDV increased significantly and ESV was unchanged. As a consequence, LV ejection fraction rose from 48%±8% to 52%±10% and from 48%±7% to 51%±6%, respectively (both P