Prevalence of left ventricular systolic dysfunction and heart failure in high risk patients: Community based epidemiological study
Davis RC., Hobbs FDR., Kenkre JE., Roalfe AK., Hare R., Lancashire RJ., Davies MK.
Objectives: To determine the prevalence of left ventricular systolic dysfunction, and of heart failure due to different causes, in patients with risk factors for these conditions. Design: Epidemiological study, including detailed clinical assessment, electrocardiography, and echocardiography. Setting: 16 English general practices, representative for socioeconomic status and practice type. Participants: 1062 patients (66% response rate) with previous myocardial infarction, angina, hypertension, or diabetes. Main outcome measures: Prevalence of systolic dysfunction, both with and without symptoms, and of heart failure, in groups of patients with each of the risk factors. Results: Definite systolic dysfunction (ejection fraction < 40%) was found in 54/244 (22.1%, 95% confidence interval 17.1% to 27.9%) patients with previous myocardial infarction, 26/321 (8.1%, 5.4% to 11.6%) with angina, 7/388 (1.8%, 0.7% to 3.7%) with hypertension, and 12/208 (5.8%, 3.0% to 9.9%) with diabetes. In each group, approximately half of these patients had symptoms of dyspnoea, and therefore had heart failure. Overall rates of heart failure, defined as symptoms of dyspnoea plus objective evidence of cardiac dysfunction (systolic dysfunction, atrial fibrillation, or clinically significant valve disease) were 16.0% (11.6% to 21.2%) in patients with previous myocardial infarction, 8.4% (5.6% to 12.0%) in those with angina, 2.8% (1.4% to 5.0%) in those with hypertension, and 7.7% (4.5% to 12.2%) in those with diabetes. Conclusion: Many people with ischaemic heart disease or diabetes have systolic dysfunction or heart failure. The data support the need for trials of targeted echocardiographic screening, in view of the major benefits of modern treatment. In contrast, patients with uncomplicated hypertension have similar rates to the general population.