Late results of CABG for postinfarction angina--relation to preoperative myocardial infarct size

We evaluated the late results of coronary bypass grafting (CABG) in 85 patients. The patients were divided into two groups according to preoperative MI size estimated by the Selvester QRS score; 24 with MI size of larger than 20% of LV muscle (group A; average 28 +/- 11%), and 61 with MI size smaller than 20% (group B; average 10 +/- 9%). New York Heart Association classes of both groups following CABG improved significantly (from 2.8 +/- 0.7 to 1.3 +/- 0.4 in group A; p less than 0.01, from 2.5 +/- 0.6 to 1.2 +/- 0.5 in group B; p less than 0.01). There was higher incidence of serious ventricular arrhythmias in group A than in group B (83% vs. 21%, p less than 0.01). In Group A, LVEF and LVESVI did not improve following CABG (from 17 +/- 9 to 16 +/- 8 mmHg, from 39 +/- 15 to 40 +/- 15%, from 66 +/- 28 to 69 +/- 40 ml/M2), while in Group B, those improved significantly (from 13 +/- 6 to 11 +/- 5 mmHg; p less than 0.01, from 53 +/- 14 to 58 +/- 10%; p less than 0.01, from 39 +/- 23 to 32 +/- 14 ml/M2; p less than 0.05). The exercise-to-rest LVSWI ratios increased significantly following CABG in both groups (from 86 +/- 25 to 160 +/- 56% in group A; p less than 0.05, from 92 +/- 31 to 140 +/- 37% in group B; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)