(FIT)-Module 1, Workshop 1: Electrocardiographic/Electrophysiologic Correlation-London Case 9 Answer

Video Transcription

Video Summary

The video explains that mutations in the ryanodine receptor cause delayed after depolarizations (DADs) and triggered activity due to abnormal calcium leakage from the sarcoplasmic reticulum (SR), leading to arrhythmias. During exercise or high catecholamine states, this results in spontaneous SR calcium release. Calcium is exchanged via the sodium-calcium exchanger, creating an inward current and potentially triggering action potentials. This process is linked to catecholaminergic polymorphic ventricular tachycardia (CPVT), characterized by arrhythmias during stress but a normal ECG at baseline. The video distinguishes CPVT from other conditions like Long QT syndrome and arrhythmogenic cardiomyopathy.

Keywords

ryanodine receptor mutations

delayed after depolarizations

calcium leakage

catecholaminergic polymorphic ventricular tachycardia

arrhythmias during stress