Cardiovascular magnetic resonance assessment of myocardial injury in patients treated with immune checkpoint inhibitors.

Abstract

Background: Immune checkpoint inhibitors (ICIs) are first-line treatments for various malignancies. Case studies represent fulminant myocarditis, and there is uncertainty in the prevalence of subclinical myocardial injury (MI) due to ICI. Therefore, this study sought to assess MI in patients treated with ICI utilising biochemical markers and advanced cardiac imaging. Methods: In this prospective, multicentre study, ICI treatment-naïve patients with no significant prior cardiovascular history were enrolled. Primary outcome was: prevalence and severity of cardiac Troponin I (cTnI) at 6 weeks following ICI. Secondary outcomes were: MI by cardiovascular magnetic resonance (CMR), ΔLV-GLS measured by 2D-transthoracic echocardiography (TTE), ΔNT-ProBNP, and major adverse cardiac events (MACE) 6 weeks post ICI. Results: Of 85 patients screened, 44 were excluded. Within the remaining 41 patients, mean age was 68 years (63% male). Four died before follow-up, 37 patients had baseline and follow-up data. Baseline and follow-up parameters are highlighted in Table 1. Twenty patients (54%) underwent CMR. Ten (50%) patients had CMR evidence of MI – 10 (50%) elevated T1 mapping, one (7%) elevated T2 mapping, and nine (45%) non-ischaemic mid-wall LGE. Nine of 10 (90%) participants with CMR evidence of MI had previously been treated with chemotherapy and/or radiotherapy. In segments with abnormal T1 mapping/LGE on CMR, there were matching LV-GLS abnormalities in the baseline TTE. These LV-GLS abnormalities persisted in the follow-up CMR (Table 3 (p=0.0023) in the basal anterior segment. Major adverse cardiovascular events occurred in one patient (2.4%) and one (2.4%) patient with ICI-induced pericarditis. Conclusion: These results suggest that CMR findings represent pre-existing subclinical myocardial dysfunction prior to ICI. The absence of significant cTnI increases support. Larger studies are warranted to confirm the cardiac safety of ICI.