Screening for coronary artery disease after mediastinal irradiation in Hodgkin lymphoma survivors.

Abstract

8568 Background: Cardiovascular diseases are the most common non-malignant cause of death in Hodgkin Lymphoma (HL) survivors, especially those who had mediastinal irradiation as part of their treatment. We investigated the role of CT coronary angiography (CTA) as a screening tool for coronary artery disease (CAD) in asymptomatic HL survivors, related findings to stress testing and subsequent interventions. We also evaluated acceptance of screening. Methods: Patients were eligible if at least 10 years disease-free and treated with mediastinal radiotherapy. All patients were screened with ECG, stress testing and CTA. Primary endpoint was significant CAD (stenosis >50%) on CTA. A sample size of 50 patients would achieve ≥80% power to detect a difference of 13% (≥20% vs a population proportion of 7%) using a two-sided binominal test. Allowing for non-evaluable and false-positive scans, we considered CTA screening to be indicated for testing in a larger population if in ≥six patients revascularization would be necessary. Results: Fifty-two patients were included, 48 patients underwent CTA. Median age was 47 years, time since HL diagnosis 21 years. Most patients had no risk factors for CAD. There were 45 evaluable scans. Prevalence of significant CAD on CTA was found in 20% (N=9), and significantly increased compared to the 7% expected abnormalities (p=0.01, 95% CI 8.3-31.7%). In 5 of the 8 patients who underwent conventional angiography, significant CAD was confirmed, and revascularization performed. Two patients were started on medication. Stress testing was inaccurate for determining CAD: all participants were asymptomatic and 1 patient with significant CAD had signs of ischemia. Ninety percent of the participants were content with the screening offered in this study, regardless whether the CTA showed abnormalities or not. Conclusions: Prevalence of significant CAD among HL survivors is high. In our participants even the most severe and life-threatening CAD was not preceded by typical symptoms. In symptomatic cardiac patients revascularization improves survival. This might justify both screening by CTA and intervention in this asymptomatic population, but needs to be further evaluated in a larger cohort. Clinical trial information: NCT01271127.