ECG CHALLENGE: Focal Atrial Tachycardia Mimicking Flutter: Diagnosis Clarified by Ladder Diagrams.

Abstract

We present the case of a 75-year-old man with a history of hypertension, type 2 diabetes, and concentric left ventricular hypertrophy who presented with palpitations. The initial electrocardiogram suggested atrial flutter; however, detailed analysis using a ladder diagram revealed a focal atrial tachycardia with alternating 2:1 and 3:1 conduction. Some deflections initially interpreted as flutter waves were identified as T waves, highlighting the importance of differentiating true atrial activity from ventricular repolarization. The presence of exit block further supported a focal origin. This case underscores the value of ladder diagrams in accurately interpreting complex supraventricular arrhythmias.