Objectives: This retrospective study attempted to relate surgical outcome with the extent and type of preoperative wall motion asynergy in patients with postinfarction myocardial scar who underwent endoventricular circular patch plasty repair and associated coronary grafting.
Background: Left ventricular (LV) pump function improvement is difficult to predict after aneurysmectomy, for either akinetic or dyskinetic scar, and previous studies have reported that the absence of paradoxic systolic motion correlates with higher operative mortality and no improvement in pump function.
Methods: Two hundred forty-five patients who underwent endoventricular circular patch plasty repair and associated coronary grafting were retrospectively selected if they had technically adequate right and left anterior LV angiograms before the operation. All had right and left cardiac catheterization. The centerline method was applied to preoperative right anterior oblique LV angiography to assess the absolute motion of the chords and the percent length of the perimeter showing a fractional shortening <2 SD from the normal mean value (extent of asynergy ([A%]).
Results: The overall perioperative mortality rate was 6%; 120 patients had akinetic and 125 had dyskinetic scar, and no differences were found among the groups in terms of all the clinical and hemodynamic variables collected in the study. Patients with a large scar (A% >60), either akinetic or dyskinetic, had a higher perioperative mortality rate (12%) than patients with a small scar (2.2%). After the operation, the ejection fraction (EF) increased from 36 +/- 13% to 50 +/- 13% (mean +/- SD), and pulmonary pressures significantly decreased. End-diastolic volume decreased from 199 +/- 75 to 89 +/- 36 ml/m2. Patients with a large akinetic scar had the most severely impaired preoperative function (largest ventricular volumes and highest pulmonary mean pressure); nevertheless, they had an impressive improvement in function (EF from 25 +/- 9% to 41 +/- 12%), not different from that observed with large dyskinetic scarring (EF from 26 +/- 7% to 46 +/- 11%).
Conclusions: Surgical outcome of endoventricular circular patch plasty repair for postinfarction myocardial scar relates to the extent of LV asynergy rather than to the presence or absence of dyskinesia. Patients with a large akinetic scar and severely depressed pump function benefit from a relatively simple surgical procedure previously reserved only for dyskinetic aneurysm. The reduction of wall tension and oxygen demand, owing to the marked decrease of volumes, and the increase in oxygen supply, owing to revascularization, may play a major role in improving pump function.