Intermittent PR Prolongation During Narrow QRS Complex Tachycardia.

BACKGROUND

The coexistence of focal atrial tachycardia (AT) originating from the left atrial appendage (LAA) with dual atrioventricular nodal pathways (DAVNP) is uncommon and presents distinct ablation challenges.

CASE SUMMARY: A 31-year-old female woman with intermittent palpitations for 1 year was referred to our medical center for catheter ablation after an abnormal electrocardiogram. There was no personal or family history of cardiovascular disease or congenital anomalies.

DISCUSSION: This case highlights the diagnostic complexity of a rare apical LAA-origin AT with DAVNP that required comprehensive electrophysiological study for confirmation. Successful focal ablation was achieved, prioritizing this strategy over LAA isolation given patient-specific factors and anatomical challenges.

TAKE-HOME MESSAGE: The diagnosis of apical LAA AT with DAVNP is extremely challenging on electrocardiogram, requiring comprehensive mapping for diagnosis and for guiding a successful, individualized ablation strategy.