Home-Based Exercise Training Improves Left Ventricle Diastolic Function in Survivors of Childhood ALL: A Tissue Doppler and Velocity Vector Imaging Study.

BACKGROUND

Advanced echocardiographic methods may reveal signs of late anthracycline cardiac toxicity (ACT) even in asymptomatic patients. We studied echocardiographic tissue Doppler imaging (TDI) and velocity vector imaging (VVI) in long-term survivors of childhood acute lymphoblastic leukemia (ALL) before and after an exercise intervention.

METHODS

Twenty-one asymptomatic, anthracycline-treated, long-term childhood ALL survivors with matched controls were studied at baseline. Seventeen of the survivors participated in a 3-month home-based exercise program. Echocardiography with TDI and VVI was performed.

RESULTS

At baseline, ejection fraction (60.7 ± 4.7% vs. 62.3 ± 3.7%, P = 0.22) and fractional shortening (32.6 ± 3.1% vs. 34.0 ± 2.8%, P = 0.13) were similar in survivors and controls. Lateral early diastolic mitral annulus velocity E' (32.81 ± 5.71 cm/sec vs. 38.03 ± 6.21 cm/sec, P = 0.01), E'/A' (1.60 ± 0.48 vs. 2.07 ± 0.63, P = 0.01), and E/E' (2.78 ± 0.35 vs. 2.42 ± 0.62, P = 0.04) were impaired compared to controls. Peak circumferential strain and strain rate were attenuated at apex (-24.50 ± 3.46% vs. -28.06 ± 4.39%, P = 0.01 and -1.47 ± 0.22 sec(-1) vs. -1.68 ± 0.33 sec(-1) , P = 0.02) compared to controls. After the intervention, early diastolic mitral inflow velocity E (87.76 ± 12.54 cm/s vs. 95.28 ± 10.48 cm/s, P = 0.04) and E' increased (31.78 ± 5.50 cm/s vs. 34.96 ± 5.41 cm/s, P < 0.01). Peak circumferential systolic and diastolic strain rates at mid-level (-1.22 ± 0.21 sec(-1) vs. -1.35 ± 0.24 sec(-1) , P = 0.04 and 1.25 ± 0.25 sec(-1) vs. 1.48 ± 0.35 sec(-1) , P < 0.01) improved after the exercise program.

CONCLUSIONS

A simple home-based exercise program improved cardiac function in asymptomatic childhood ALL survivors. Adding TDI in routine echocardiographic examination may improve the recognition of early signs of ACT, and VVI may bring additional information. The improvements in cardiac function after the exercise program emphasize the importance of physical activity in this population.