The STOP-MED CTRCD Trial

Cancer therapy-related cardiac dysfunction (CTRCD) is when the heart's ability to pump oxygenated blood to the body is compromised. It is a side effect of cancer therapy which can occur as commonly as in 1 in 5 patients. When this occurs, heart failure medications are started to protect the heart from progressing to heart failure. With early detection and treatment, heart function recovers to normal in \>80% of patients. Unfortunately, heart failure medications are associated with an undesirable long-term pill burden, financial costs, and side-effects (e.g., dizziness and fatigue). As a result, cancer survivors frequently ask if they can safely stop their heart failure medications once their heart function has returned to normal. Currently there is no scientific evidence in this area of Cardio-Oncology. To address this knowledge gap, the investigators have designed a randomized control trial to assess the safety of stopping heart failure medication in patients with CTRCD and recovered heart function. The investigators will enrol patients who have completed their cancer therapy and are on heart medications for their CTRCD, which has now normalized. The investigators will randomize patients with no other reasons to continue heart failure medications (e.g., kidney disease) to continuing or stopping their heart medications safely. All patients will undergo a cardiac MRI at baseline, 1 and 5 years with safety assessments at 6-8 weeks, 6 months and 3 and 5 years. The investigators will determine if stopping medications is non-inferior to continuing medications by counting the numbers of patients who develop heart dysfunction by 1 year in each group.