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[Cardiac rhythm and conduction disorders in polymyositis and dermatomyositis]
Klinicheskaia Meditsina
|December 29, 1998
Summary
Polymyositis and dermatomyositis (PM/DM) can cause heart rhythm and conductivity issues, particularly in acute phases. Early detection through exercise testing may reveal subtle myocardial contractility defects.
Area of Science:
- Cardiology
- Rheumatology
- Internal Medicine
Background:
- Polymyositis (PM) and dermatomyositis (DM) are idiopathic inflammatory myopathies.
- Cardiac involvement is a known complication, but its specific manifestations require further elucidation.
Purpose of the Study:
- To evaluate cardiac rhythm and conductivity in patients with PM and DM.
- To identify potential correlations between cardiac abnormalities and disease activity markers.
Main Methods:
- Electrocardiogram (ECG) and 24-hour Holter monitoring.
- Enzyme-linked immunosorbent assay (EIA) for creatine kinase MB-fraction (CK-MB) and myoglobin.
- Echocardiography and Doppler echocardiography.
- Assessment of intracardiac hemodynamics and myocardial contractility at rest and during exercise.
Main Results:
- Supraventricular and ventricular extrasystoles were maximal in acute PM/DM.
- Left anterior bundle branch block was most frequent in acute/subacute PM-DM, correlating with elevated CK-MB and myoglobin.
- No resting alterations in intracardiac hemodynamics or myocardial contractility were observed.
Conclusions:
- Cardiac rhythm and conductivity disturbances are present in PM/DM, especially during acute phases.
- Exercise testing is recommended to detect early myocardial contractility defects in these patients.
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