This will be a cohort study of all patients receiving Cluster of Differentiation 19 (CD19)-specific CAR T cell therapy for relapsed/refractory B cell haematological malignancies. Patients will receive cardiac assessment and have serum cardiac biomarkers, ECG, transthoracic echocardiogram and cardiac magnetic resonance imaging performed at baseline prior to CAR T cell therapy, 7 days post CAR T cell infusion, and 3 months post CAR T cell infusion. Abnormalities in these cardiac investigations will be used to demonstrate cardiac injury and identify which patients are most at risk of developing cardiac injury related to CAR T cell therapy.

CD19-specific chimeric antigen receptor (CAR) T cells are a novel therapy for relapsing or refractory blood cancers, which have delivered a significant improvement in the rates of complete and partial remission. However, they are associated with toxicities, with some of early evidence suggestive of cardiovascular involvement. Despite this, the full extent of cardiovascular toxicity is poorly understood.

This research study seeks to understand the cardiac safety of CAR T cells in patients who receive this therapy as part of standard care for relapsed/refractory B-cell blood cancer. They will be assessed for cardiovascular risk factors via history, blood biomarkers, and cardiac imaging tests. These parameters will be repeated at 7 days following administration of the CAR T cells or if there are signs of cardiovascular deterioration, and again at 3 months follow up.

The aim is to predict the cohort most at risk of cardiovascular toxicity, and demonstrate evidence of cardiac injury on the cardiac imaging scans.

Inclusion Criteria:

• Patients with capacity, (aged 16 and older)
• Undergoing CAR T cells for treatment for relapsing or refractory haematological malignancies

Exclusion Criteria:

• Patients under 16 years

All patients receiving CD19-specific CAR T cell therapy for the management of relapsing or refractory haematological malignancy at the MacMillan Cancer Centre within the University College London Hospital will be considered for participation.