Abstract 6918: Cardiovascular Magnetic Resonance Imaging Features and Prognostic Value in Immune Checkpoint Inhibitor-Induced Myocarditis

• Published in: Circulation (New York, N.Y.) Vol. 144; no. Suppl_1; p. A6918
• Main Authors: Cadour, Farah, Cautela, Jennifer, Rapacchi, Stanislas, Varoquax, Arthur, Habert, Paul, Arnaud, Francois, Jacquier, Alexis, Meilhac, Alexandra, Paganelli, Franck, Lalevee, Natalie, Scemama, Ugo, Thuny, Franck
• Format: Journal Article
• Language: English
• Published: Lippincott Williams & Wilkins 16-11-2021
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/circ.144.suppl_1.6918

IntroductionImmune checkpoint inhibitor (ICI)-induced myocarditis (ICI-M) is an emerging and severe complication of cancer treatment, for which diagnosis and risk stratification are challenging. Very few data exist on CMR findings and predictive value in ICI-M. HypothesisWe hypothesized that ICI-M would have specific CMR features, and we sought to explore the prognostic value of CMR. MethodsIn this case-control multicenter study, the clinical, biological, and CMR findings (including late gadolinium enhancement [LGE], T1/T2 mapping, and extracellular volume fraction [ECV] values) of adults with ICI-M (n=33) were compared with those of two other groups, including cancer patients without myocarditis scheduled to receive ICIs (w/o-M, n=21), and patients with non-ICI-induced myocarditis (NI-M, n=85). As secondary objective, we explored the potential value of LGE and T1/T2/ECV for predicting major adverse cardiovascular events (MACE) in ICI-M patients. ResultsCompared with w/o-M, the global native T1, ECV, and T2 z-scores were significantly higher in ICI-M (P<0.001 for T1, P=0.03 for ECV, and P=0.004 for T2). LGE was more frequently observed in ICI-M than in w/o-M (82% vs. 9%, P<0.001). The sensitivity of the main 2018-Lake Louise criteria was only 61% and the specificity was 100% in the diagnosis of ICI-M. No significant difference was found between ICI-M and NI-M in terms of the global native T1, ECV, and T2 z-scores. LGE was less frequent in ICI-M (82% vs. 100%, P<0.001) but was more likely to involve the midwall layer (P<0.001) and septal segments (P<0.001) than in NI-M. For ICI-M patients, septal LGE was the only CMR predictor of MACE even after adjustment for age, sex, risk factors, left ventricular ejection fraction<50%, and magnitude of increase in peak troponin I or T (adjusted hazard ratio, 3.57; 95% CI, 1.26-10.18; P=0.02). ConclusionsICI-M demonstrates specific features on CMR, and septal LGE may be a predictor of poor prognosis.