RT Book, Section A1 Kiefer, Todd A1 Granger, Christopher B. A1 Jackson, Kevin P. A2 Papadakis, Maxine A. A2 McPhee, Stephen J. A2 Rabow, Michael W. A2 McQuaid, Kenneth R. SR Print(0) ID 1193147651 T1 Mechanisms of Arrhythmias T2 Current Medical Diagnosis & Treatment 2023 YR 2023 FD 2023 PB McGraw-Hill Education PP New York, NY SN 9781264687343 LK accessmedicine.mhmedical.com/content.aspx?aid=1193147651 RD 2024/03/28 AB Susceptibility to arrhythmias may result from genetic abnormalities or acquired structural heart disease. Susceptibility may be increased by electrolyte abnormalities, hormonal imbalances (thyrotoxicosis, hypercatecholaminergic states), hypoxia, medication effects (such as QT interval prolongation or changes in automaticity, conduction, and refractoriness), and myocardial ischemia. Ongoing research has provided important information on the genetic basis of arrhythmias and knowledge in this arena is expanding rapidly. Most arrhythmias can be classified as (1) disorders of impulse formation or automaticity, (2) abnormalities of impulse conduction, (3) reentry, and (4) triggered activity.