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Sinoatrial conduction abnormalities - an underestimated cardiac complication in women with systemic sclerosis
Elżbieta Kramarz1, Lidia Rudnicka2, Zbigniew Samochocki2
1Internal Medicine and Cardiology Department, Military Institute of Medicine, Warsaw, Poland.
Insights
Systemic sclerosis (SSc) patients face higher risks of sinoatrial conduction abnormalities, including SA-block and prolonged SACT. Skin severity independently predicts these cardiac issues, necessitating focused ECG monitoring in SSc care.
Area of Science:
- Cardiology
- Rheumatology
- Electrophysiology
Background:
- Systemic sclerosis (SSc) is linked to cardiac arrhythmias and conduction disorders.
- The specific risk of sinoatrial conduction abnormalities in SSc remains unclear.
Purpose of the Study:
- To determine the incidence of sinoatrial conduction abnormalities in SSc patients.
- To investigate the relationship between these abnormalities and SSc clinical features.
Main Methods:
- Forty women with SSc underwent 24-hour ambulatory ECG monitoring.
- Evaluated sinoatrial conduction time (SACT) and type I second-degree sinoatrial block (SA-block).
- Assessed the impact of clinical descriptors on sinoatrial conduction.
Main Results:
- Prolonged SACT (>150 ms) occurred in 50% of patients (20/40).
- SA-block was observed in 35% of patients (14/40).
- SSc skin manifestation severity independently predicted SA-block and prolonged SACT.
Conclusions:
- SSc patients have an increased risk of SA-block and prolonged SACT.
- The severity of skin involvement is a key factor associated with these cardiac conduction abnormalities.
- 24-hour ambulatory ECG monitoring in SSc should include assessment for sinoatrial conduction disorders.
Introduction:
It has been claimed that patients with systemic sclerosis (SSc) have an increased risk of developing cardiac arrhythmias and atrioventricular conduction disorders, but it is unknown whether SSc may be a cause of sinoatrial conduction abnormalities.
Aim:
To establish the incidence of sinoatrial conduction abnormalities in patients with SSc and verify the relationship of these disorders with various clinical descriptors of SSc.
Material And Methods:
Forty women with systemic sclerosis of varying duration and severity underwent 24-hour ambulatory ECG monitoring. The occurrence of type I second-degree sinoatrial block (SA-block) and calculation of sinoatrial conduction time (SACT) were evaluated to establish the incidence of sinoatrial conduction abnormalities. The measurements of SACT were obtained using spontaneous atrial premature beats. The effect of various clinical descriptors on sinoatrial conduction abnormalities was assessed.
Results:
The mean ± SD SACT for the 40 patients was 150 ±15 ms. Prolonged (> 150 ms) SACT was found in 20 patients. In 14 (35%) patients SA-block occurred during ambulatory ECG monitoring. The discriminant analysis identified the severity of SSc cutaneous manifestation as an independent marker for developing SA-block (p < 0.005) and SACT prolongation (p < 0.0002).
Conclusions:
Patients with SSc are at an increased risk of developing type I second-degree sinoatrial block and prolonged sinoatrial conduction time. The occurrence of these abnormalities is related to the severity of skin involvement. Therefore, cardiological diagnosis using 24-hour ambulatory ECG in this group of patients should be focused also on this type of disorders. Prospective, controlled studies are needed to assess their prognostic role.
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