Cardiac Outcomes in Adult Survivors of Childhood Cancer Exposed to Cardiotoxic Therapy A Cross-sectional Study

Background: Studies of cardiac disease among adult survivors of childhood cancer have generally relied on self-reported or registry-based data. Objective: To systematically assess cardiac outcomes among survivors of childhood cancer. Design: Cross-sectional study. Setting: St. Jude Children's Research Hospital. Patients: 1853 adult survivors of childhood cancer, aged 18 years or older, who received cancer-related cardiotoxic therapy at least 10 years earlier. Measurements: Baseline history and physical examination, fasting metabolic and lipid panels, echocardiography, electrocardiography, and 6-minute walk test. Results: One half of the survivors (52.3%) were men with a median age of 8 years (range, 0 to 24 years) at cancer diagnosis and 31 years (range, 18 to 60 years) at evaluation. Cardiomyopathy was present in 7.4% survivors (newly identified at the time of evaluation in 4.7%), coronary artery disease in 3.8% (newly identified in 2.2%), valvular regurgitation or stenosis in 28.0% (newly identified in 24.8%), and conduction or rhythm abnormalities in 4.4% (newly identified in 1.4%). Nearly all survivors were asymptomatic. The prevalence of cardiac conditions increased with age at evaluation, ranging from 3% to 24% among survivors aged 30 to 39 years to 10% to 37% among those aged 40 years or older. In multivariable analysis, survivors exposed to anthracycline doses of 250 mg/m(2) or more had greater odds of cardiomyopathy (odds ratio, 2.7 [ 95% CI, 1.1 to 6.9]) than those who were not exposed. Survivors exposed to heart radiation also had increased odds of cardiomyopathy (odds ratio, 1.9 [ CI, 1.1 to 3.7]) compared with those who were not exposed. Radiation exposure greater than 1500 cGy with any anthracycline exposure conferred the greatest odds for valve findings. Limitations: Sixty-one percent of survivors exposed to anthracycline chemotherapy or cardiac-directed radiation participated. A comparison group and longitudinal assessments were not available. Conclusion: Cardiovascular screening identified considerable subclinical disease among adult survivors of childhood cancer.