Transient Atrioventricular Block Secondary to Coronary Artery Embolism From Infective Endocarditis Following CAR T‐Cell Therapy

Figures

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  FIGURE 1. Serial Electrocardiograms Before and After CAR T‐cell Therapy. (A) Baseline electrocardiogram (ECG) showing normal sinus rhythm 3 days prior to admission. (B) ECG on hospital Day 45, demonstrating third‐degree atrioventricular (AV) block with a ventricular rate of 38 beats/min. (C) ECG on hospital Day 49, following the recovery of intrinsic rhythm, showing a newly developed incomplete right bundle branch block.

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  FIGURE 2. Cardiac Magnetic Resonance Imaging. Cardiac magnetic resonance imaging performed on the 51st hospital day, 6 days after the onset of atrioventricular block. (A) Native T1 map, (B) T2‐weighted black‐blood image, and (C) late gadolinium enhancement image at the mid‐ventricular short‐axis level. There is no myocardial edema on T1 and T2 imaging, and late gadolinium enhancement imaging demonstrates no enhancement, with no findings to suggest myocarditis or macroscopic infarction.

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  FIGURE 3. Postmortem Pathological Findings of the Heart and Conduction System. (A–D) Macroscopic view of the epicardial coronary arteries showing mild atherosclerosis without significant stenosis. (E) Macroscopic view of the right ventricular side; subendocardial hemorrhage is observed at the AV junction of the basal interventricular septum (yellow arrow). (F) Macroscopic view of the aortic valve demonstrating vegetations (bacterial colonies) at the commissure between the right coronary cusp (RCC) and non‐coronary cusp (NCC) (yellow arrow). (G) Histopathological image of the vegetation showing bacterial colonies entangled within fibrin and neutrophil clusters (Hematoxylin–eosin [H‐E] stain). (H) Gross sections of the AV conduction system, including the AV node (AVN) and the His bundle (HIS). (I, J) Microscopic examination of the conduction system at the level of right bundle branch revealing localized coagulative necrosis and bacterial aggregates concentrated around the His bundle area. In panel J, a septal branch artery supplying the proximal conduction system is occluded by septic embolic material (arrow). RVOT; right ventricular outflow tract. LV, left ventricle. The necrotic and…