BACKGROUND: Arrhythmias are one of the typical complications of primary aldosteronism (PA), is commonly characterized by hypertension and hypokalemia. CASE REPORT: In this report, we present 3 cases of subjects in whom primary aldosteronism manifested with life-threatening arrhythmias. In 2 subjects, after excluding organic heart disease, an implantable cardioverter defibrillator was inserted and, only after the second episode of polymorphic ventricular tachycardia accompanied with low plasma potassium levels, the diagnosis of primary aldosteronism was made. CONCLUSIONS: It is important to include diagnosis of primary aldosteronism in the diagnostic work-up of hypertensive subjects without any structural cardiovascular impairment who present with malignant arrhythmia and hypokalemia. Appropriate treatment of primary aldosteronism may avoid insertion of an implantable cardioverter defibrillator.

3rd Medical Department of the 1st Faculty of Medicine and General Teaching Hospital Prague Czech Republic