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

Workshop 1_Electrocardio_London_2025_case 1 answer

Video Transcription

Video Summary

The exercise stress test is useful in diagnosing long QT syndrome types 1 and 2 by showing QT interval prolongation during exercise and early recovery. Long QT type 1 results from KCNQ1 gene mutations affecting the potassium channel, leading to prolonged QT interval and risk of arrhythmias at fast heart rates. Type 2, due to KCNH2/ HERG mutations, shows T-wave abnormalities. Type 3 stems from SCN5A mutations affecting sodium channels. NADALOL is highly effective for preventing arrhythmias and sudden death in long QT1 patients, even those with asymptomatic gene mutations, and outperforms other beta blockers for primary prevention.

Keywords

Long QT syndrome

QT interval prolongation

KCNQ1 gene mutations

NADALOL effectiveness

arrhythmia prevention