Refractory Arrhythmias as a Potential Indicator of Underlying Cardiac Amyloidosis: A Case Report

Primary (AL) amyloidosis is a rare multisystemic disorder that occurs approximately in 9.7-14.0 cases per million per year in the United States. A late diagnosis of amyloidosis can decrease the chance of survival to less than three years. With the intention to diagnose future cases of AL amyloidosis early in clinical presentation, we describe a case of a 64-year-old female who had presented to the hospital for a pre-liver transplant workup for presumed end-stage liver disease secondary to nonalcoholic steatohepatitis (NASH). Pre-transplant electrocardiogram (ECG) findings were significant for atrial fibrillation that was unable to resolve with synchronized cardioversion. Two previous cardioversions attempted in the preceding three years with amiodarone proved unsuccessful. Following her ECG, an endoscopy and colonoscopy were completed that demonstrated a lesion within the gastric mucosa along with two polyps in the transverse colon and ascending colon. Pathology for these lesions revealed amyloidosis in all biopsy sites, which was followed by a bone marrow biopsy also confirming AL amyloidosis and proliferative monoclonal B lymphocytes. A cardiac magnetic resonance imaging (MRI) proceeded to gather more information on the systemic extent of the patient's amyloidosis, which showed signs consistent with cardiac infiltration of amyloid. The patient was discharged with at-home hospice care and later decided to pursue chemotherapy, ultimately expiring from end organ failure. We conclude that failed cardioversion in a patient with persistent atrial fibrillation can be a clinical and diagnostic marker in suspecting a diagnosis of amyloidosis. Thus, we encourage clinicians to consider systemic amyloidosis in the assessment of unsuccessful cardioversion in these patient presentations for the initiation of treatment early on in the disease course.