The diagnosis of heart failure in general practice: implications for the UK National Service Framework.

BACKGROUND: The UK National Service Framework recommends patients with suspected heart failure undergo echocardiography. Selection of patients for this investigation in primary care is difficult. It is not clear which clinical features best identify patients with left ventricular systolic dysfunction.

AIM: Using echocardiography, to establish the accuracy of primary care diagnosis of left ventricular systolic dysfunction. To investigate the sensitivity, specificity and predictive values of clinical features in the diagnosis of left ventricular systolic dysfunction.

STUDY: A cross-sectional study of 621 patients from a population prescribed loop diuretics in 7 general practices.

METHOD: Clinical diagnoses were extracted from general practice records. Symptoms, clinical signs, ECG features, brain natriuretic peptide levels and echocardiographic findings were studied in a research clinic.

RESULTS: Left ventricular systolic dysfunction (ejection fraction <40%) was present in 50% of 621 patients prescribed loop diuretics in primary care. General practice diagnoses showed high false positive rates. Individual or combinations of clinical features did not accurately predict left ventricular systolic dysfunction.

CONCLUSION: These results suggest the clinical diagnosis of left ventricular systolic dysfunction is inaccurate in this population. General practitioners should have a low threshold for referring patients prescribed loop diuretics for echocardiography. Increased open access echocardiography facilities will be needed.