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The evolution of electrocardiographic changes in patients with Duchenne muscular dystrophies
Woo Hyun Yoo1, Min-Jung Cho1, Peter Chun1
1Department of Pediatrics, Biomedical Research Institute, Pusan National University Hospital, Busan, Korea.
Insights
Fragmented QRS (fQRS) on ECGs may be an early indicator of cardiac changes in Duchenne muscular dystrophy. These electrocardiographic abnormalities become more prominent with age in patients with this condition.
Area of Science:
- Cardiology
- Neuromuscular Disorders
- Medical Diagnostics
Background:
- Duchenne muscular dystrophy (DMD) inevitably leads to myocardial dysfunction and dysrhythmias.
- Early detection of cardiac involvement is crucial for managing DMD patients.
Purpose of the Study:
- To evaluate specific electrocardiographic (ECG) changes that indicate the progression of cardiomyopathy in Duchenne muscular dystrophy.
- To identify early markers of myocardial changes in DMD.
Main Methods:
- Retrospective analysis of 50 ECGs from 30 DMD patients (ages 1-27) and 116 age-matched healthy controls.
- Analysis of heart rate, fragmented QRS (fQRS), corrected QT, Tpeak-to-Tend, and Tpeak-to-Tend/QT intervals.
Main Results:
- DMD patients showed an increasing trend in fQRS prevalence, corrected QT, corrected Tpeak-to-Tend, and Tpeak-to-Tend/QT over time.
- Significant differences in fQRS were observed in younger patients (≤10 years).
- Multiple ECG parameters, including fQRS and heart rate, showed significant differences in older age groups (11-15 and ≥16 years).
Conclusions:
- Higher prevalence of fQRS in young DMD patients suggests it may be an early sign of myocardial changes.
- Depolarization and repolarization abnormalities become increasingly prominent in DMD patients over 10 years old.
- Further research is needed to validate these ECG findings in DMD cardiomyopathy.
Purpose:
Myocardial dysfunction and dysrhythmias are inevitable consequences of Duchenne muscular dystrophy. We aimed to evaluate specific trends of electrocardiographic changes that reflect the progress of cardiomyopathy in patients with Duchenne muscular dystrophy.
Methods:
Fifty electrocardiograms (ECGs) of 30 patients (ages 1 to 27 years) who had not been prescribed medications for heart failure treatment at the time of examination were retrospectively analyzed and compared with 116 ECGs of age-matched healthy 116 controls. Heart rate, leads with fragmented QRS (fQRS), corrected QT, Tpeak-to-Tend, and Tpeak-to-Tend/QT were analyzed.
Results:
The patients with Duchenne muscular dystrophy failed to show a normal age-related decline in heart rate but showed an increasing trend in the prevalence of fQRS, corrected QT, corrected Tpeak-to-Tend, and Tpeak-to-Tend/QT over time. In the ≤10-year-old patient group, a significant difference was found only in the prevalence of fQRS between the patients and the controls. The prevalence of fQRS, heart rate, Tpeak-to-Tend/QT, and corrected Tpeak-to-Tend demonstrated significant differences between the patients and the controls in the middle age group (11 to 15 years old). All the indexes were statistically significantly different in the ≥16-year-old patient group.
Conclusion:
The prevalence of lead with fQRS representing regional wall motion abnormalities was higher in the young patients than in the young healthy controls, and this might be one of the first signs of myocardial change in the patients. Markers of depolarization and repolarization abnormalities were gradually prominent in the patients aged >10 years. Further studies are needed to confirm these findings.
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