Effect of Radiotherapy on the Right Ventricular Function in Lung Cancer Patients

Background: Anticancer treatment is associated with many side effects, including those involving the cardiovascular system. While many studies are available on the effects of radiotherapy (RT) on the left ventricle (LV), studies are lacking on the early effects of RT on the structure and function of the right ventricle (RV). Our study aims to assess, using modern echocardiographic techniques, the effect of irradiation on RV systolic function in the mid-term follow-up of patients undergoing RT for lung cancer (LC). Methods: This single-center, prospective study included consecutive patients with LC who were referred for treatment with definite radiotherapy and chemotherapy (study group) or chemotherapy only (control group). Results: The study included 43 patients with a mean age of 64.9 ± 8.1 years. Cancer treatment-related RV toxicity (CTR-RVT) was found in 17 patients (40%). Early reductions in TAPSE values were observed among patients in the study group (20.3 mm vs. 22.1 mm, p = 0.021). Compared to baseline, there was a significant reduction in RV global longitudinal strain (RV GLS) in the study group immediately after the treatment (−21.1% vs. −18.4%, p = 0.02) and also at 3 months after RT (−21.1% vs. −19.1%, p = 0.021). A significant reduction in the RV FWLS value was also observed at 3 months after the end of the treatment (−23.8% vs. −21.8, p = 0.046). There were no significant changes in the three-dimensional right ventricular ejection fraction (3DRVEF) during the follow-up. We found a correlation (p = 0.003) between the mean dose of radiation to the RV and 3DRVEF when assessed immediately after RT. The mean dose of radiation to the heart correlated with RV free-wall longitudinal strain (RV FWLS) immediately after RT (p = 0.03). Conclusions: RV cardiotoxicity occurs in nearly half of patients treated for lung cancer. TAPSE is an important marker of deterioration of RV function under LC treatment. Compared to 3DRVEF, speckle tracking echocardiography is more useful in revealing deterioration of RV systolic function after radiotherapy.