Pre- and postoperative left ventricular pressure-volume relationships in patients undergoing partial left ventriculectomy

Objective. The early effects of partial left ventriculectomy and mitral val vuloplasty (the Batista operation) were studied by analyzing pre- and posto perative left ventricular (LV) pressure-volume (PV) relationships. Methods. Between July and October 1996, 32 patients underwent the Batista p rocedure with PV relationship analysis immediately before and after surgery . Patients were 52 +/- 14 years of age with reduced functional capacity (3. 68 +/- 0.46, New York Heart Association) due to cardiomyopathy (13), ischem ic disease (13), valvular disease (3) and Chagas' disease (3). Results. The Batista operation required cardiopulmonary bypass for 44 +/- 2 5 min with the heart arrested in 10 patients for 27 +/- 22 min only for CAB G (8), AVR (2) and autotransplantation (2). Changes in the actual PV relati onship included a drastic reduction in the end-diastolic (EDV) and end-syst olic volume (ESV), resulting in no change in stroke volume (SV). Pulmonary artery wedge pressure (PAW) decreased despite elevated end-diastolic pressu re (EDP). Ejection fraction (EF), Emax, unstressed-ventricular volume (V-0) preload recruitable stroke work (Msw) and its volume intercept (Vsw) all i mproved and resulted in similar stroke work (SW) with less energy expenditu re, PVArea (PVA), improving myocardial energetic efficiency (EE = SW/PVA). When preload and afterload (arterial elastance) were standardized to avoid influence of perioperative changes in loading conditions, SV decreased more than 10% in 21 (65.6%) patients (deteriorated) and increased more than 10% in 6 (18.8%) patients (improved), with 5 (15.6%) showing no significant ch ange. Conclusion. The results suggest that the Batista procedure improves systoli c function but decreases diastolic compliance, resulting in reduced ventric ular function immediately after surgery. Thus, immediate hemodynamic improv ements appear to derive mainly from a reduced severity of the mitral regurg itation Improved myocardial energetics may ameliorate Ventricular function and improve the course of underlying myocardial disease.