Abstract Aims Hodgkin lymphoma is a highly curable disease, with survival rates around 85% at 5 years, thanks to its treatment, mainly based on radiation therapy alone or in association with chemotherapy. However, radiation therapy carries the risk of long-term complications, mainly represented by secondary malignancies or cardiovascular diseases. Indeed, patients treated with radiation remain at increased risk of coronary artery disease, congestive heart failure, valve disease, pericardial disease and sudden death. In particular, radiation-induced valve disease has been reported in approximately 10% of treated patients, with the most common being aortic or mitral regurgitation, followed by aortic stenosis. We describe the case of a very severe aortic valve stenosis developed 35 years after radiotherapy for Hodgkin Lymphoma. Methods A 60-years-old woman with history of Hodgkin Lymphoma treated with radiotherapy 35 years ago, no cardiovascular risk factors, complained progressive fatigue and worsening dyspnoea. She was referred to our centre from a spoke centre for congestive heart failure caused by aortic stenosis. At her arrival, we performed a transthoracic echocardiography finding a very-severe aortic stenosis (mean gradient 97 mmHg, AVA 0.3 cm2), a moderate functional mitral regurgitation and an important hypertrophy suspected of infiltrative pattern. No coronary artery disease was found at coronary angiography. Furthermore, she underwent a cardiac magnetic resonance showing a moderate left ventricular dilatation and hypertrophy with areas of non-ischaemic late gadolinium enhancement, significant for myocardial fibrosis with no specific pattern of infiltration. She was treated with surgical aortic valve replacement with biological prosthesis (Inspiris Resilia 21) with good results at the discharge echocardiography. Discussion Cardiovascular toxicity is nowadays the most common non-malignancy cause of death in radio-treated cancer survivors. At the level of the valvular apparatus, radiation damage is expressed with fibrosis of the myocardium and of the valvular endothelium, leading to thickening and calcification especially of the left-sided valves. Radio-treated patients have a 50% cumulative incidence of cardiovascular diseases at 40 years after treatment, and a clinically-relevant valve disease is found in approximately 6% of radio-treated patients at 20 years. Conclusions Thus, an early identification of the disease in a subclinical state is crucial. Nevertheless, there is still no consensus on the timing and the modality of cardiovascular screening after radiation therapy. Moreover, an elevated cardiovascular risk profile was found to be directly related to cardiotoxicity; this underlines the importance of identification and aggressive treatment of cardiovascular risk factors. Radiation dose reduction and the use of shields may further reduce the incidence of late cardiovascular complications in these patients.