Electrocardiography in 110 patients with systemic sclerosis: a cross-sectional comparison with population-based controls

Abstract

Objectives: Patchy fibrosis of the myocardium is thought to cause conduction abnormalities in patients with systemic sclerosis (SSc). We compared the prevalence and type of rhythm/conduction disturbances in 74% of the SSc patients in Stockholm County and controls.

Method: A total of 110 SSc patients (age 62 ± 12 years) fulfilling the American College of Rheumatology (ACR) criteria for SSc and 105 gender- and age-matched controls participated in this study. A 12-lead resting electrocardiogram (ECG) was performed in all participants. The first 49 patients and 42 controls also underwent a 22–24-h Holter ECG recording. Associations with disease subsets, autoantibodies, cardiovascular risk factors, and left ventricular ejection fraction (LVEF), as estimated by echocardiography, were investigated.

Results: Abnormal ECGs were found in 28% of patients and 17% of controls (p = 0.05). Atrioventricular (AV) and/or intraventricular (IV) conduction abnormalities were found in 15% of patients and 5% of controls (p < 0.01). Four patients, but no controls, had low anteroseptal R-wave/septal Q-wave patterns with narrow QRS complexes, simulating a septal wall infarction pattern. Patients had more abnormal Holter ECG recordings than controls (38% vs. 17%, p = 0.05). All participants with a normal resting ECG had an LVEF ≥ 50%.

Conclusions: Although ECGs are inexpensive, commonly available screening tools, to detect arrhythmias, such as frequent ventricular extrasystoles (VES), Holter tracings should be performed. The frequencies of AV and/or IV conduction abnormalities and septal Q waves/low R waves have not changed since 1985. The unmet need of anti-fibrotic treatment in SSc is underscored by these findings.

Acknowledgements

Financial support was obtained through the Swedish Heart–Lung Foundation, the Swedish Research Council, the Swedish Rheumatism Association, King Gustaf V’s 80th Birthday Fund, the Swedish Society of Medicine, ALF funding from Stockholm County Council, and Karolinska Institutet.