Early repolarization with horizontal ST segment may be associated with aborted sudden cardiac arrest: a retrospective
Sung Hea Kim1, Do Young Kim, Hyun-Joong Kim
1Department of Internal Medicine, Konkuk University School of Medicine, Konkuk, South Korea.
BMC Cardiovascular Disorders
|December 12, 2012
Summary
Early repolarization pattern (ERP) with a horizontal ST segment is more common in sudden cardiac arrest survivors without structural heart disease. This finding suggests ST-segment morphology is valuable for identifying malignant early repolarization.
Area of Science:
- Cardiology
- Electrophysiology
- Sudden Cardiac Arrest Research
Background:
- Risk stratification of early repolarization pattern (ERP) is crucial for identifying malignant cases.
- A horizontal ST segment in J-point elevation has been proposed as a marker for malignant ERP.
- This study investigates the prevalence of ERP with a horizontal ST segment in sudden cardiac arrest (SCA) survivors without structural heart disease.
Purpose of the Study:
- To examine the prevalence of ERP with a horizontal ST segment in SCA survivors without structural heart disease.
- To evaluate the utility of ST-segment morphology in risk stratifying the ERP.
- To identify potential markers for malignant early repolarization.
Main Methods:
- Retrospective review of 83 SCA survivors (August 2005-August 2010), including 25 without structural heart disease.
- Control group of 60 healthy subjects matched for age, sex, and comorbidities (diabetes, hypertension).
- ERP defined as J-point elevation ≥0.1 mV in ≥2 inferior/lateral leads; horizontal ST segment defined as <0.1 mV within 100 ms post-J point.
Main Results:
- The prevalence of ERP with a horizontal ST segment was significantly higher in SCA survivors (20%) compared to controls (3.3%, p=0.021).
- J-point elevation >2 mm was also more frequent in SCA survivors (16%) than controls (1.7%, p=0.025).
- No significant difference in overall ERP prevalence or corrected QTc between groups.
Conclusions:
- The higher prevalence of ERP with a horizontal ST segment in SCA survivors suggests its utility as a marker for malignant early repolarization.
- ST-segment morphology, specifically a horizontal pattern, aids in recognizing high-risk ERP.
- This finding supports the use of ST morphology in risk stratification for patients with early repolarization patterns.
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