Prognosis in patients with heart failure and preserved left ventricular systolic function.

BACKGROUND: It is recognized that heart failure patients with preserved left ventricular systolic function have better prognosis; nevertheless, there are some studies with conflicting results. Also, there is a paucity of data concerning the prognostic factors in this group of patients. OBJECTIVES: To determine possible variables with prognostic relevance in heart failure patients with preserved left ventricular systolic function (ejection fraction > 40%). METHODS: 157 consecutive ambulatory patients with heart failure were assessed; those patients with ejection fraction > 40% were included in the study (n = 46). All patients were evaluated by clinical interview and physical examination, ECG, echocardiogram (M-mode, 2D and pulsed Doppler of mitral flow), biochemical study and determination of type B natriuretic peptide (BNP). The patients were grouped according to the rhythm presented on ECG: Group I--patients with atrial fibrillation; Group II--patients in sinus rhythm Group II was further subdivided in two groups according to the presence or absence of restrictive left ventricular filling pattern. All patients had a clinical follow-up, with recording of events (death or hospitalization from cardiac cause). The mean follow-up time was 682.2 +/- 55 days. RESULTS: The mean age of the patients was 70.4 +/- 1.2 years; 54.3% were women; mean ejection fraction was 49.6 +/- 1%; mean BNP levels were 202.9 +/- 41.3 pg/ml. Mortality was 19.6% and the combined event death or hospitalization from cardiac cause) occurred in 26.1% of the patients. Among the clinical, demographic, biochemical, echocardiographic and neurohumoral parameters, only BNP levels had prognostic significance in the whole population. In Group II patients, BNP levels, heart rate and restrictive left ventricular filling pattern were identified as having prognostic significance. Kaplan-Meyer curve analysis showed that both BNP and restrictive left ventricular filling pattern seemed to be important prognostic markers. CONCLUSIONS: This preliminary study suggests thar neurohumoral activity (determined by plasma BNP levels) and a restrictive ventricular filling pattern may be important factors in prognostic stratification of heart failure patients with preserved left ventricular systolic function.