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

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.