Left atrium size and the risk of cardiovascular death in middle-aged men

Abstract

Background: The echocardiographic identification of subclinical risk markers may enhance risk stratification for the development of cardiovascular outcomes in the general population. Although echocardiography is widely used in the evaluation of cardiac structures and function, the prognostic value of echocardiographic assessment of left atrium (LA) size for risk stratification of cardiovascular death is unknown.

Methods: Left ventricular (LV) mass and LA size were measured by using M-mode echocardiography in a representative population-based sample of 830 men (age, 42-61 years) from eastern Finland. There were 54 deaths due to cardiovascular disease during an average follow-up of 13 years.

Results: The strongest risk factors for cardiovascular death were smoking, family history of coronary heart disease, low exercise capacity, elevated blood pressure, exercise-induced myocardial ischemia, and large LA diameter. Men in the highest tertile of LA diameter (>43 mm) had a 2.3-fold (95% confidence interval, 1.1-5.0) risk of cardiovascular death compared with men in the lowest tertile of LA diameter (<39 mm), after adjusting for other risk factors and the use of antihypertensive medications. The excess risk for cardiovascular mortality appeared to reside largely in the highest tertile of LA size. After additional adjustment for LV mass, the relation between LA size and mortality did not remain statistically significant (relative risk, 1.5; 95% confidence interval, 0.8-4.1; P = .15) in this group.

Conclusions: This prospective population-based study shows that echocardiographically defined LA diameter was directly related to the risk of cardiovascular death. The association of LA enlargement to cardiovascular death appears to be partially related to LV hypertrophy.