Exercise echocardiography revealed that high-risk asymptomatic childhood cancer survivors had lower resting E/A ratios than controls (1.4 vs. 2.0, P=0.008), but this difference resolved with exercise.
Cross-Sectional (n=80)
Does exercise echocardiography better detect subclinical cardiac dysfunction compared to resting echocardiography in asymptomatic childhood cancer survivors treated with anthracyclines?
Routine exercise echocardiography may not be a useful surveillance tool to assess anthracycline cardiotoxicity in asymptomatic pediatric cancer survivors, as they are able to compensate for mild resting diastolic dysfunction during exercise.
Absolute Event Rate: 1.4% vs 2%
p-value: p=0.008
BACKGROUND: Surveillance for anthracycline cardiotoxicity in cancer survivors typically utilizes resting M-mode and two-dimensional echocardiography, which are insensitive to detection of subtle myocardial changes. We examined childhood cancer survivors treated with anthracyclines during exercise using various echocardiography techniques to investigate if these tools can better detect subclinical cardiac dysfunction. PROCEDURE: We recruited asymptomatic survivors at least five years post treatment. Echocardiography was performed at rest and at termination of exercise utilizing tissue Doppler techniques and strain rate imaging. RESULTS: Eighty participants were characterized by cardiotoxicity risk status (high 12, moderate 23, low 24, no risk 21) as defined by the Children's Oncology Group Long Term Follow-Up Guidelines v3.0. The high-risk group had a higher resting heart rate than controls (100 vs. 88 bpm P for trend = 0.049). Peak aerobic capacity in all groups was similar. Compared to controls at rest, the high-risk group had evidence of diastolic dysfunction with lower E/A ratios (1.4 vs. 2.0, P = 0.008) and higher septal early diastolic velocities (E/E') of 11.7 versus 9.9 (P = 0.165). With exercise, this difference resolved and myocardial contractile reserve was preserved. CONCLUSIONS: Asymptomatic, pediatric cancer survivors at high-risk for anthracycline cardiotoxicity have some evidence of diastolic filling abnormalities at rest. With exercise, they augment their systolic and diastolic function to achieve normal maximal aerobic capacity suggesting they are able to compensate for mild cardiac dysfunction in the early years after exposure. Additionally, findings suggest that routine exercise echocardiography may not be a useful surveillance tool to assess anthracycline cardiotoxicity.
Ryerson et al. (2014) conducted a cross-sectional in Childhood cancer survivors treated with anthracyclines (n=80). Exercise echocardiography vs. Controls (no risk group) was evaluated on Resting E/A ratio (p=0.008). Exercise echocardiography revealed that high-risk asymptomatic childhood cancer survivors had lower resting E/A ratios than controls (1.4 vs. 2.0, P=0.008), but this difference resolved with exercise.