PREDICTION OF IMPROVEMENT IN RECENT-ONSET CARDIOMYOPATHY AFTER REFERRAL FOR HEART-TRANSPLANTATION

Objectives. The purpose of this investigation was to determine how oft en left ventricular function improves in recent onset dilated cardiomy opathy of sufficient severity to cause referral for heart transplantat ion and how to predict this improvement at the time of evaluation for transplantation. Background. Improvement has been reported to occur fr equently in patients with acute dilated cardiomyopathy but has not bee n described specifically in these patients referred for transplantatio n. To avoid potentially needless transplantation, it would be useful t o know the frequency of improvement and how to predict it in these pat ients. Methods. A consecutive series of 297 patients with primary dila ted cardiomyopathy evaluated for heart transplantation was reviewed to identify those with onset of heart failure symptoms within the preced ing 6 months and to examine their outcome. The clinical, echocardiogra phic, hemodynamic and laboratory profiles of patients with improvement in left ventricular function (defined as an increase in left ventricu lar ejection fraction greater than or equal to 0.15 to a final ejectio n fraction of greater than or equal to 0.30) were compared with those of patients without improvement to assess which variables might predic t improvement. Results. Of 49 patients with recent onset dilated cardi omyopathy, 13 (27%) showed improvement, with an increase in mean left ventricular ejection fraction from 0.22 +/- 0.08 to 0.49 +/- 0.09. All patients with improvement had survived without heart transplantation at 43 +/- 29 months. Survival time was shorter in the remaining 36 pat ients without improvement with recent onset cardiomyopathy than in the 248 with chronic symptoms (p = 0.03) and in younger compared with old er patients with recent onset cardiomyopathy (p = 0.0001). By multivar iate analysis, predictors of improvement were shorter duration of symp toms, lower pulmonary wedge and right atrial pressures and higher seru m sodium levels. Conclusions. A minority of patients with dilated card iomyopathy and symptoms for less than or equal to 6 months will have m arked improvement in left ventricular function, after which prognosis is excellent despite previous referral for heart transplantation. Thos e with symptom duration >3 months and more severe initial decompensati on as reflected by higher filling pressures and lower serum sodium lev els are unlikely to show improvement and may require earlier considera tion for heart transplantation.