Spontaneous alternans in Brugada ECG morphology
Amir Farjam Fazelifar1, Majid Haghjoo, Arash Arya
1Department of Pacemaker and Electrophysiology, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. fazelifar@rhc.ac.ir
Summary
Sick sinus syndrome can alter Brugada ECG patterns. Heart rate changes affect Brugada electrocardiogram morphology, suggesting ion current and autonomic tone influence.
Area of Science:
- Cardiology
- Electrophysiology
- Medical Diagnostics
Background:
- Sick sinus syndrome (SSS) is a cardiac arrhythmia affecting the heart's natural pacemaker.
- Brugada syndrome is a genetic disorder characterized by abnormal electrocardiogram (ECG) findings and an increased risk of sudden cardiac death.
- The interplay between SSS and Brugada ECG patterns requires further investigation.
Observation:
- A 23-year-old male patient presented with coexisting sick sinus syndrome and a Brugada-like ECG pattern.
- The Brugada ECG pattern exhibited dynamic changes based on heart rate variations.
- Specifically, a coved type (Type 1) ECG converted to a saddleback configuration (Type 2) with decreased R-R intervals (faster heart rate) and reverted to coved type with increased R-R intervals (slower heart rate).
Findings:
- The study observed a direct correlation between R-R interval length and Brugada ECG pattern morphology in a patient with SSS.
- These dynamic ECG changes were independent of stable heart rate conditions.
- The findings suggest that autonomic tone and the kinetics of cardiac ion currents play a significant role in modulating these Brugada-like patterns.
Implications:
- This case highlights the importance of considering heart rate variability in the interpretation of Brugada ECG patterns, especially in patients with arrhythmias like SSS.
- Understanding the influence of autonomic tone and ion channel kinetics can refine diagnostic approaches and risk stratification for Brugada syndrome.
- Further research is warranted to explore the mechanisms underlying these rate-dependent ECG changes in Brugada-like phenotypes.
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