Channelopathy linking KCNH2 mutation and primary aldosteronism: a case of life-threatening torsades de pointes.

Primary aldosteronism (PA) typically presents with hypertension and hypokalemia; however, its presentation as life-threatening ventricular arrhythmias is rare and often underrecognized. We report a case of a 30-year-old woman who presented with polymorphic ventricular tachycardia manifesting as torsades de pointes. Laboratory findings revealed persistent hypokalemia, metabolic alkalosis, suppressed renin, and inappropriately elevated aldosterone. Because recurrent malignant arrhythmia conferred a high immediate risk of sudden cardiac death, genetic testing for inherited arrhythmia syndromes was initiated, and an implantable cardioverter-defibrillator was implanted for secondary prevention before genetic confirmation became available. Endocrine evaluation proceeded concurrently and ultimately established the diagnosis of PA. Subsequent genetic analysis identified a pathogenic splice-site variant in KCNH2, consistent with congenital long QT syndrome type 2 (LQTS2). A review of the literature identified 16 previously reported cases of PA-associated ventricular arrhythmia, which showed a consistent association with hypokalemia and hypertension; however, none included genetic evaluation. This case highlights the need for parallel endocrine and arrhythmia evaluation in patients with unexplained ventricular arrhythmias.