Persistent Epsilon-Like Wave After Right Atrial Myxoma Resection: A Case Report.

Epsilon waves are a major electrocardiographic criterion of arrhythmogenic right ventricular cardiomyopathy (ARVC), but have also been described in inflammatory and infiltrative cardiomyopathies. Postoperative arrhythmias, most commonly atrial fibrillation, are well recognized following atrial myxoma resection; however, persistent epsilon-like activity in the absence of residual disease has not been previously documented. We report the case of a 46-year-old woman presenting with exertional dyspnea and vertigo who was found to harbor a large pedunculated right atrial myxoma on transthoracic echocardiography. Surgical excision yielded a 35-gram tumor, with histopathology revealing chronic inflammatory infiltrates and hemorrhagic foci. Postoperative imaging confirmed normalization of right-sided pressures with no residual mass, correlating with symptomatic resolution. Nevertheless, follow-up electrocardiography at eight months demonstrated a persistent epsilon-like deflection in lead V1, accompanied by right-sided conduction delay and T-wave inversion, while other nonspecific abnormalities resolved. The persistent ARVC-mimicking phenotype likely reflects localized fibrotic and inflammatory conduction system remodeling, aligning with mechanistic data that inflammation and matrix remodeling can delay right ventricular activation. This rare electrophysiological sequela of right atrial myxoma carries notable implications for rhythm surveillance and long-term risk stratification. Furthermore, future research should explore the role of immunophenotyping and advanced imaging in predicting postoperative recovery and facilitating targeted therapeutic strategies.