Ethnic differences in the prevalence and aetiology of left ventricular systolic dysfunction in the community: the Harrow heart failure watch.

To assess ethnic differences in the prevalence and aetiology of left ventricular systolic dysfunction (LVSD) in the community. Community cohort study. All patients underwent echocardiography and those found to have LVSD underwent myocardial perfusion imaging with or without coronary angiography to diagnose underlying coronary artery disease (CAD). Seven representative general practices in Harrow, UK, a community hospital, and a local district general hospital. 1392 patients >or= 45 years old randomly selected from the computer records of seven general practices. The prevalence and aetiology of LVSD in the community, assessing differences between white and non-white populations, and the proportion of patients with LVSD with undiagnosed CAD. 734 patients (53%) attended, 518 (71%) white and 216 (29%) non-white, the majority South Asian. Thirty nine patients (5.5%) had probable LVSD and 25 (3.5%) definite LVSD. No significant differences in prevalence were seen with ethnicity. CAD underlay most cases of LVSD. Non-white patients had a higher prevalence of CAD as the underlying aetiology of significant LVSD than white patients (100% v 56%, p = 0.04) and a trend towards less alcoholic cardiomyopathy. 8% of patients with LVSD had undiagnosed CAD. LVSD is common. White and non-white patients have a similar overall prevalence of LVSD. Non-white patients, the majority South Asians in this study, have a higher prevalence of CAD as the underlying cause for LVSD than white patients. CAD underlies most cases of LVSD in the community, although it may be undiagnosed unless formally assessed.