Isolated atrial myocarditis presenting with atrial arrhythmias and diffuse thickening of the atrial wall diagnosed via atrial biopsy: a case report.

ABSTRACT:

Background

Isolated atrial myocarditis is rarely diagnosed in non-open-heart surgical cases. We report a case of isolated lymphocytic atrial myocarditis presenting with atrial arrhythmias, syncope, and atrial wall thickening, confirmed histologically by transcatheter atrial biopsy and multimodality imaging.

Case summary

A 69-year-old woman presented to the emergency department with general fatigue and a syncopal episode. Electrocardiogram revealed sick sinus syndrome (SSS) with a heart rate of 40 beats/min. Laboratory tests indicated a mild inflammatory response without cardiac enzyme level elevation. Transthoracic echocardiography demonstrated left atrial wall thickening and mild pericardial effusion. Contrast-enhanced computed tomography revealed a thrombus in the left atr

SUBMITTER: Edayoshi M 

PROVIDER: S-EPMC12798813 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature