This analysis sought to evaluate the clinical characteristics and outcome in heart
failure with mild systolic dysfunction.
Although heart failure with mild systolic dysfunction occurs commonly, this is an
understudied area because clinical trials have usually excluded patients with ejection
fraction >35%.
The 422 patients with left ventricular ejection fraction </=35% were compared with
172 with a left ventricular ejection fraction >35% in the Vasodilator in Heart Failure
Trial (V-HeFT I), whereas in V-HeFT-II 554 patients with a left ventricular ejection
fraction </=35% were compared with 218 patients with a left ventricular ejection fraction
>35% for mortality and clinical care. For a left ventricular ejection fraction >35%,
treatment with hydralazine/isosorbide dinitrate was compared with prazosin and placebo
therapy in V-HeFT I, and hydralazine/isosorbide dinitrate was compared with enalapril
in V-HeFT II for mortality, clinical course and change in physiologic variables: ejection
fraction, plasma norepinephrine levels, ventricular tachycardia and echocardiographic
variables.
In both studies, patients with a left ventricular ejection fraction >35% differed
principally in hypertensive history, higher functional capacity and radiographic and
echocardiographic cardiac dimension from patients with a left ventricular ejection
fraction </=35%, and plasma norepinephrine levels differed in V-HeFT II (p < 0.01).
Patients with a left ventricular ejection fraction >35% had a lower cumulative mortality
than those with a left ventricular ejection fraction </=35% (p < 0.0001) and less
frequent hospital admissions for heart failure (p < 0.014, V-HeFT I; p < 0.005, V-HeFT
II). Although cumulative mortality and morbidity did not differ between treatment
groups in V-HeFT I, enalapril decreased overall mortality versus hydralazine/isosorbide
dinitrate (p < 0.035) in V-HeFT II. For physiologic variables in V-HeFT II, enalapril
decreased ventricular tachycardia at follow-up (p < 0.05).
In V-HeFT, heart failure with mild systolic dysfunction was associated with different
characteristics and a more favorable prognosis than heart failure with more severe
systolic dysfunction. Enalapril decreased overall mortality and sudden death compared
with hydralazine/isosorbide dinitrate. Prospective trials are needed to address therapy
for heart failure with mild systolic dysfunction.