Clinical features and prognosis associated with a preserved left ventricular systolic function in a large cohort of congestive heart failure outpatients managed by cardiologists. Data from the Italian Network on Congestive Heart Failure.

BACKGROUND: The aim of this study was to evaluate the clinical characteristics, 1-year prognosis and therapeutic approach of heart failure with a preserved left ventricular systolic function in a large multicenter registry of patients referred to specialized heart failure clinics.
METHODS: The study population consisted of 5164 outpatients (mean age 62 +/- 12 years, 78.8% male, 28.1% in NYHA functional class III-IV) with an available left ventricular ejection fraction (LVEF) measurement at the initial evaluation for enrollment in the Italian Network on Congestive Heart Failure. A 1-year follow-up was available for 2390 patients.
RESULTS: 2859 out of 5164 patients (55.4%) had an LVEF < 35%, 1618 (31.3%) had an LVEF between 35 and 45%, and 687 patients (13.3%) had an LVEF > 45%. Patients with an LVEF > 45% were significantly older, more often female and presented a significantly higher prevalence of a hypertensive etiology, obesity and atrial fibrillation. The severity of the clinical picture, as indicated by a lower prevalence of NYHA class III-IV (17.2 vs 35.6%, p = 0.001) and a third heart sound (14.8 vs 33.5%, p = 0.001), was less in patients with an LVEF > 45%. The therapeutic approach differed significantly, with a larger use of calcium antagonists and beta-blockers in patients with an LVEF > 45%, while ACE-inhibitors, diuretics and digoxin were more often prescribed to those with an impaired LVEF. The 1-year mortality and morbidity (all cause and congestive heart failure worsening hospitalizations) were significantly lower in patients with a preserved left ventricular systolic function compared to those with left ventricular systolic dysfunction (8.9 vs 18.8% for mortality, p = 0.001, and 8.3 vs 16.5% for hospital readmissions due to worsening congestive heart failure, p = 0.001, respectively).
CONCLUSIONS: Patients with congestive heart failure and a preserved left ventricular systolic function seem to constitute a distinct population not infrequently presenting even in the clinical setting of specialized heart failure clinics. Further studies are needed to establish a definitive and standardized diagnosis and the most appropriate therapy for congestive heart failure with a normal LVEF.