Severe and Reversible Left Ventricular Dysfunction Due to Slow Atrial Tachycardia Masquerading as Sinus Tachycardia.

ABSTRACT:

Background

Arrhythmia-induced cardiomyopathy is a reversible cause of heart failure but is often underrecognized, particularly with subtle or slow atrial tachycardia (AT) with 1:1 atrioventricular conduction.

Case summary

A 55-year-old man with prior mitral valve surgery and dual-chamber implantable cardioverter-defibrillator presented with fatigue and dyspnea. Echocardiography revealed ejection fraction decline from 40% to 45% to 20% to 25%. Device interrogation suggested abnormal atrial histograms. Electrophysiological study confirmed slow AT (tachycardia cycle length: 600-630 milliseconds), and activation mapping demonstrated a microreentrant circuit near the mitral valve. Radiofrequency ablation terminated the arrhythmia, and ejection fraction returned to baseline within

SUBMITTER: Alhaj E 

PROVIDER: S-EPMC12905689 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature