Influência da redução da pré-carga sobre o índice de desempenho miocárdico (índice de Tei) e outros parâmetros Doppler ecocardiográficos da função ventricular esquerda

Abstract

To assess the influence of preload reduction by hemodialysis on Doppler Tei Index of myocardial performance and other parameters of cardiac function. The Tei index and left ventricular (LV) systolic and diastolic function parameters were estimated, before and after a single hemodialysis session. Only subjects who were in sinus rhythm, without history of coronary artery disease, and no evidence of cardiac valve disease and pericardial effusion were included in the study. Fifteen patients (8 men, mean age 53 +/- 14 years) completed the study. After an ultrafiltration of 2.2 +/- 1.1 liters, peak mitral E velocity decreased (p < 0.05) and A velocity remained unchanged (p = ns), resulting in reduction of E/A ratio (p < 0.01). The Tei index increased (from 0.57 +/- 0.07 to 0.65 +/- 0.09, p < 0.01) because of significant prolongations in isovolumetric relaxation time (from 101 +/- 14 to 113 +/- 17 ms, p < 0.01) and ejection time (from 271 +/- 22 to 252 +/- 22, p < 0.05). The isovolumetric contraction time did not vary (p = ns). There was no change in diastolic tissue Doppler parameters, while systolic velocities increased (p < 0.05). The Tei index was affected by hemodialysis-induced preload alterations, as well as other mitral inflow Doppler-derived parameters. The diastolic parameters of mitral annulus Doppler tissue were independent of preload, while systolic velocities suggested improved systolic function.