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Published on: June 16, 2020
Cardiac conduction disturbances in mixed connective tissue disease
Summary
Cardiac conduction disturbances affect approximately 20% of patients with mixed connective tissue disease. These disturbances, while common, do not appear to significantly impact the disease
Area of Science:
- Cardiology
- Rheumatology
- Internal Medicine
Background:
- Myocardial involvement is observed in approximately 20% of mixed connective tissue disease (MCTD) patients.
- Cardiac conduction disturbances are a potential manifestation of MCTD.
Purpose of the Study:
- To determine the prevalence of cardiac conduction disturbances in MCTD patients.
- To investigate the association between conduction disturbances and other MCTD manifestations.
Main Methods:
- A cohort of 113 MCTD patients was studied.
- Patients were categorized into groups with (n=23) and without (n=90) conduction disturbances.
- Clinical course, treatment, disease duration, conduction disturbance types, and systemic alterations were analyzed over a mean follow-up of 10.2 years.
Main Results:
- Conduction disturbances were present in about 20% of MCTD patients, predominantly women.
- Anterior hemiblock was the most common conduction alteration, associated with significant QRS axis differences.
- No significant differences in disease outcome were found between groups with and without conduction disturbances.
Conclusions:
- Cardiac conduction disturbances occur in 20% of MCTD patients, consistent with existing literature.
- These disturbances did not influence the overall disease outcome in this cohort.
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