The echocardiographic changes and functional outcome from mitral valve repair, combined with partial left ventriculectomy (PLV), the Batista procedure, were investigated. From May 1996 to August 1997 the operation was performed on 57 patients, primarily (95%) transplant candidates with idiopathic dilated cardiomyopathy. All had been Class IV (36.8% had improved to Class III by the time of surgery) on medical therapy, including 40% hospitalized on inotropes and 3 patients on intra-aortic balloon pumps. The mean cardiac index was 2.1+/-0.6 L/min/m2, with a wedge pressure of 24+/-8 mm Hg, and norepinephrine levels of 855+/-500 pg/mL (normal 80-526 pg/mL). There were 2 in-hospital mortalities (3.5%). At 3 months there were significant persistent changes in LV end-diastolic diameter (8.1+/-1.0 cm-6.3+/-0.9 cm) and ejection fraction (13.6+/-6%-23+/-7.7%). Subjective improvement included a mean change in NYHA functional class from 3.7 to 2.2, and objective changes included improvement in peak oxygen consumption from 10.6+/-4 mL/kg/min to 15.4+/-4.5 mL/kg/min. Actuarial survival at 1 year was 82.1%; and freedom from death, relisting for transplantation, and need for LVAD support was 58%. The earliest "learning curve" experience with this relatively unstudied operation warrants careful investigation. Many questions remain to be answered, but many patients have demonstrated early subjective and objective improvement.