Second Presentation:
Six-months after the initial presentation, the patient again presented
to the emergency department with severe, sharp, mid-substernal chest
pain with associated diaphoresis, and lightheadedness. He remained
physically active including frequent exercise. Physical exam including
orthostatic vitals was unremarkable. Electrocardiogram showed sinus
bradycardia at 40 bpm without ST elevation or depression and a right
ventricular conduction delay with an epsilon wave (Image 2), which were
new findings compared to prior. Troponins continued to rapidly and
markedly increase in addition to elevations of transaminases and
inflammatory markers (Table 1). Infectious work-up including covid-19
PCR was negative. Cardiac angiography revealed no coronary artery
disease but a very prominent mid LAD myocardial bridge with near
complete obliteration at resting HR in 70s. A repeat echocardiogram
showed a new reduction in EF to 40-45% and diffuse hypokinesis of the
LV (in comparison to six months earlier).
A repeat CMR three months after the previous scan (2ndCMR study) revealed new findings of mildly reduced LV systolic function
with mild-moderate hypokinesis of the mid to apical lateral wall, and
prominent epicardial fibrosis and an area of small, focal mid-myocardial
fibrosis in a non-ischemic pattern with elevated native T1 and T2 values
on mapping, respectively (Image 4). Of note, the study still did not
meet any CMR criteria for ARVC. The patient subsequently received an
endomyocardial biopsy without any significant histologic changes
reported. Genetic testing demonstrated one pathogenic variant in the JUP
gene in our patient, along with multiple genetic abnormalities for ARVC
in his mother including abnormal JUP, NEBL and ACTN2 genes. Given these
genetic results along with his family history, the patient was referred
for an ICD implant for primary prevention of sudden cardiac death along
with exercise limitation. A follow-up (3rd CMR scan)
was performed after 11 months after initial CMR scan, which showed
improvement in myocardial fibrosis (Image 5).