Abstract 18205: Changing Characteristics and Outcomes of Patients with Chronic Heart Failure due to Left Ventricular Systolic Dysfunction: a Study Across Therapeutic Eras
Background: Therapies for patients with chronic heart failure due to left ventricular systolic dysfunction have advanced substantially over the last 20 years. The overall impact of these therapies on mortality, symptoms and clinical characteristics is unclear.
Hypothesis: We hypothesised that changes in heart failure management during the past 20 years would result in improved outcomes.
Methods: Comparison of two United Kingdom prospective cohort studies of outpatients with chronic heart failure, performed between 1993 and 1995 (historic cohort), and 2006 and 2009 (contemporary cohort). After exclusion of patients with LV ejection fraction >45%, atrial fibrillation, diabetes mellitus and permanent pacemaker implant (due to differing study inclusion criteria), 280 (of an initial 533) patients were included in the historic group, and 357 (of 628) in the contemporary group. All clinical variables were assessed at study recruitment.
Results: Within the historic cohort, 83% were prescribed angiotensin converting enzyme inhibitors and 9% beta-adrenoceptor antagonists, compared to 89% and 80% respectively, in contemporary patients (p=0.02 and p<0.001 respectively). Mean NYHA functional class declined from 2.5(SEM 0.03) to 2.1(0.04) between study periods (P<0.001); mean furosemide dose requirement also fell from 79(4) to 47(3)mg (P<0.001). The prevalence of ischaemic cardiomyopathy declined from 79% to 62%, heart rate declined from 79(1) to 72(1), and left ventricular end diastolic dimension declined from 65(0.6) to 59(0.5)mm; all P<0.001. Dispersion of the QTc and QRS intervals on the 12 lead ECG declined from 85(2) to 34(1)ms, and 46(1) to 26(1)ms, respectively; both P<0.001. Crude mortality was 12.5% per annum compared to 7.8% per annum in the historic and contemporary groups respectively (P=0.04). Age-sex adjusted mortality was 49% lower in the contemporary group (P=0.01); further adjustment for ischaemic aetiology did not alter this finding (42% risk reduction; P=0.04)
Conclusion: In this cohort study of ambulant outpatients with chronic heart failure, crude and adjusted annual mortality has declined significantly. This has been accompanied by an improvement in symptoms and markers of adverse electrical and structural cardiac remodelling.
- © 2010 by American Heart Association, Inc.