Association of left atrial enlargement with left ventricular hypertrophy and diastolic dysfunction: A tissue Doppler study in echocardiographic practice

摘要

Background. Left atrial (LA) enlargement is a powerful risk factor for cardiovascular diseases; little information is available about its prevalence and correlates in subjects free of overt cardiac disease seen in echocardiographic practice. Aim. We evaluated the prevalence of LA enlargement (LAE) and the relationship with left ventricular (LV) mass and diastolic function in subjects with preserved LV systolic function referred to an echocardiographic study for routine clinical indications. Methods. 1104 subjects (mean age 58 +/- 16 years, 46% men, 57% hypertensives) underwent a comprehensive echo-Doppler examination. LAE and LV hypertrophy (LVH) were defined as LA volume index (LAVI) >29 ml/m(2) and LV mass index (LVMI) >50 g/h(2.7), respectively. Abnormalities of LV relaxation and LV filling were diagnosed by age-related thresholds of lateral annular velocity (Ei) and by early mitral flow velocity to Ei ratio (E/Ei) >= 16, respectively. Results. Overall, 10% of echocardiographic examinations fulfilled the criteria for LAE, 46% for LVH, 45% for altered LV relaxation and 5% for altered LV filling index. LVH progressively increased from 25% to 75% across LAVI quartiles. More patients in the highest quartile exhibited abnormal indexes of LV relaxation and LV filling compared with lower quartiles. In multi-variate analysis, LV mass index (beta = 0.408), age (beta = 0.188), E/Ei ratio (beta = 0.140) and Ei (beta = 0.140) emerged as major correlates of LAE (p at least <0.01 for all). Conclusions. LAE is a frequent finding in patients with preserved systolic function seen in current practice; this abnormality is strongly related to LVH and to diastolic dysfunction. Early detection of LAE may identify patients at higher cardiovascular risk and promote appropriate prevention strategies.