title: Electrical alternation.
abstract: ST segment alternans occurs relatively infrequently. However, it is seen in 30% of patients with Prinzmetal's angina, especially when the ST segment is markedly elevated. Ventricular arrhythmias occur frequently during ST segment alternation.
mesh_terms: D000328:Adult; D001145:Arrhythmias, Cardiac / Q000503:physiopathology*; D004562:Electrocardiography; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans