Cardiovascular flashlight. Atrial tachycardia in congenital left atrial appendage aneurysm: three-dimensional computed tomography imaging with electro-anatomical mapping.

A 29-year-old woman was admitted for the evaluation of atrial tachycardia (AT) associated with palpitation during exercise. She had been diagnosed with a left atrial appendage (LAA) aneurysm at the age of 19 years. She was followed by echocardiography annually because she was asymptomatic, and evidence of thrombus formation and/or atrial tachyarrhythmia was not found. She developed AT 2 months before admission. The 12-lead electrocardiogram (ECG) revealed AT with a 2:1 ventricular response ( Panel A ). The P-wave morphology indicated the origin of AT as the superior …