Long-term outcomes and reverse remodelling in recently diagnosed unexplained left ventricular systolic dysfunction.

Abstract

In patients with recently diagnosed non-ischaemic LV systolic dysfunction, left ventricular reverse remodelling (LVRR) and favourable prognosis has been documented in studies with short-term follow-up. The aim of our study was to assess the long-term clinical course and stability of LVRR in these patients. We prospectively studied 133 patients (37 women; 55 [interquartile range 46, 61] years) with recently diagnosed unexplained LV systolic dysfunction, with heart failure symptoms lasting <6months and LV ejection fraction <40% persisting after at least 1week of therapy. All patients underwent endomyocardial biopsy (EMB) at the time of diagnosis and serial echocardiographic and clinical follow-up over 5years. LVRR was defined as the combined presence of (1) LVEF≥50% or increase in LVEF≥10% points and (2) decrease in LV end-diastolic diameter index (LVEDDi)≥10% or (3) LVEDDi≤33mm/m2. LVRR was observed in 46% patients at 1year, in 60% at 2years and 50% at 5years. Additionally, 2% of patients underwent heart transplantation and 12% experienced heart failure hospitalization. During 5-year follow-up, 23 (17%) of the study cohort died. In multivariate analysis, independent predictors of mortality were baseline right atrial size (OR 1.097, CI 1.007-1.196), logBNP level (OR 2.02, CI 1.14-3.56), and PR interval (OR 1.02, CI 1.006-1.035) (P<0.05 for all). The number of macrophages on EMB was associated with overall survival in univariate analysis only. LVRR at 1year of follow-up was associated with a lower rate of mortality and heart failure hospitalization (P=0.025). In multivariate analysis, independent predictors of LVRR were left ventricular end-diastolic volume index (OR 0.97, CI 0.946-0.988), LVEF (OR 0.89, CI 0.83-0.96), and diastolic blood pressure (OR 1.04, CI 1.01-1.08) (P<0.05 for all). LVRR occurs in over half of patients with recent onset unexplained LV systolic dysfunction during first 2years of optimally guided heart failure therapy and then remains relatively stable during 5-year follow-up. Normalization of adverse LV remodelling corresponds to a low rate of mortality and heart failure hospitalizations during long-term follow-up.