HRS Board Review 2025 New Courses (Reviewers Copy)-Workshop 1_Electrocardio_London_2025

Workshop 1_Electrocardio_London_2025_case 9 answer

Video Transcription

Video Summary

Mutations in ryanodine receptors lead to delayed after depolarizations (DADs) by causing abnormal calcium leaks from the sarcoplasmic reticulum, triggering arrhythmias through the sodium-calcium exchanger. This process is linked to catecholaminergic polymorphic ventricular tachycardia (CPVT), characterized by arrhythmias during exercise or high catecholamine states. During these conditions, spontaneous calcium release occurs, creating inward currents that may trigger action potentials. In contrast, Long QT syndrome involves early after depolarizations (EADs) due to prolonged action potentials. Arrhythmogenic cardiomyopathy is associated with structural protein mutations and epsilon waves, not CPVT.

Keywords

ryanodine receptors

catecholaminergic polymorphic ventricular tachycardia

calcium leaks

delayed after depolarizations

arrhythmias