Echocardiographic assessment of left atrial ejection force and kinetic energy in chronic heart failure.

BACKGROUND: There is limited information regarding left atrial (LA) systolic adaptation to chronic heart failure (HF) in humans. Therefore, the aim of our study was to determine the LA ejection force (LAEF) and kinetic energy in patients with HF. METHODS AND RESULTS: 58 HF patients (63.8% in NYHA II) and 48 controls were studied. LA volumes were echocardiographically determined using the biplane area-length method. LA systolic function was assessed with the: (a) active emptying volume (ACTEV) and fraction (ACTEF), (b) ejection force (kdynes/m2), calculated with Manning's method [LAEF = 0.5 * rho * mitral orifice area * A2; rho: blood density, Alpha: late transmitral flow velocity] and a modification incorporating parameters of LA function [LAEFm = 0.5 * rho * LA volume at onset of atrial systole * ACTEF * A2/VTl A], and (c) kinetic energy [LA-ke (kdynes.cm/m2) = 0.5 * rho * ACTEV * A2]. LA maximal volume and ACTEV were lower (42.9 +/- 14.4 vs. 59.7 +/- 14.7 cm3, P < 0.0001; 10.9 +/- 3.3 vs. 13 +/- 3.3 cm3, P = 0.0001, respectively), whereas ACTEF (%) was higher (36.3 +/- 7 vs. 29.3 +/- 7.6 cm3, P < 0.0001) in controls than HF. LAEF, LAEFm, and LA-ke were lower in controls than HF (7.68 +/- 5.1 vs. 10.16 +/- 3.7 kdynes/m2, P = 0.006; 3.63 +/- 2.05 vs. 5.02 +/- 1.74 kdynes/m2, P = 0.0004; 2.41 +/- 1.91 vs. 3.99 +/- 2.1 kdynes.cm/m2, P < 0.0004, respectively). CONCLUSION: Despite the decreased LA systolic shortening, overall LA systolic performance is augmented in chronic HF due to LA dilation.

Left atrial remodeling in patients younger than 70 years with diastolic and systolic heart failure.

OBJECTIVE: We sought to determine left atrial (LA) volume and systolic function (LA remodeling) in younger (<70 years) patients with systolic and diastolic heart failure (HF). METHODS: In all, 32 patients with diastolic HF (left ventricular [LV] ejection fraction > or = 0.50), 26 patients with systolic HF (LV ejection fraction < 0.50), and 48 control subjects were studied. LAlpha volume (cm(3)/m(2)) was echocardiographically determined at mitral valve opening (maximal), mitral valve closure (minimal), and atrial systole (electrocardiographic Rho wave) using the biplane area-length method. The LA active emptying fraction (%) and ejection force (kdyne/m(2)) served as indices of LA systolic function. RESULTS: LA maximal volume was greater in systolic HF than diastolic HF and in the latter greater than control (68.6 +/- 13.8 vs 52 +/- 11.6 vs 42.9 +/- 14.4, respectively, P < .0001). Active emptying fraction was similar between diastolic HF and control, and greater than systolic HF (31.5 +/- 8.1 vs 36.3 +/- 7 vs 26.6 +/- 6.2, respectively, P < .0001), whereas LA ejection force was similar in diastolic and systolic HF and greater than control (5.05 +/- 1.3 vs 4.98 +/- 2.17 vs 3.63 +/- 2.05, respectively, P = .001). Vmax was related to body surface area, brain natriuretic peptide, and LV mass in diastolic HF (multiple R2 = 0.74) and to diastolic blood pressure, LV mass, and early to late transmitral flow velocity ratio in systolic HF (multiple R2 = 0.96). CONCLUSIONS: LA remodeling is more severe in systolic HF than diastolic HF and governed by different mechanisms. This may be of significant clinical relevance regarding the morbidity and mortality of these two conditions.