The Role of Left Atrial Function in Diastolic Heart Failure

ew heart failure affects 500 000 Americans yearly. Nearly 50% of these patients have a normal left ven- tricular ejection fraction (LVEF) or so-called diastolic heart failure (DHF). New onset symptomatic DHF is a lethal disease with a 5-year mortality that approaches 50%.1 Echo- Doppler techniques use LV filling patterns and tissue Doppler imaging of the mitral annulus to help identify and classify the degree of LV diastolic dysfunction, but work best in symp- tomatic patients with advanced disease.2 Therefore, the diag- nosis of early diastolic dysfunction, when asymptomatic and most treatable, remains problematic. A detailed causality-based, mechanistic understanding of what causes DHF, and how to most easily detect it, remains one of the most important unsolved problems in cardiovascular physiology and clinical cardiology.3 Article see p 10 Segmental LV deformation analysis for calculating con- tractile parameters such as strain and strain rate is now possible using noninvasive echo-Doppler techniques.2 It has been reported that LA systolic and diastolic function can also be assessed using these Doppler strain techniques.4-6 Al- though LA enlargement increases with the severity of dia- stolic dysfunction,7 the ability of LA volume measurements to discriminate asymptomatic LV diastolic dysfunction from early DHF heart failure has not been possible. However, the concept that an alteration in LA function or stiffness may indicate this change is appealing.