24-h ECG monitoring in patients with rheumatoid arthritis.

Although the main cardiac complication in patients with rheumatoid arthritis is subclinical pericarditis, mononuclear cell infiltrations into myocardium may cause cardiac arrhythmias and conduction defects. In order to examine these problems we evaluated 70 patients (53 women and 17 men) aged 18-83 years (average 56.7 +/- 11.2) with classic or definite rheumatoid arthritis, according to diagnostic criteria. Duration of the disease was 1-35 years (average 8.7 +/- 8.4). The control group comprised 70 patients admitted to hospital with degenerative joint disease, a duodenal ulcer, or who required treatment for ophthalmological or laryngeal reasons; these patients were matched for sex and age. In all patients standard 12-lead ECG investigations were performed, as well as 24-h ECG monitoring, using an Oxford Medical System device with two precordial leads CM5 and CS2, according to the Holter method. We analysed heart rate, conduction disturbances, and occurrence of arrhythmias, on the basis of generally assumed ECG criteria. Cardiac arrhythmias were found in 50% of patients with rheumatoid arthritis, and their occurrence was similar to that in the control group. Observed arrhythmias were independent of the progression of arthritis, the type of treatment administered, the familial occurrence of arthritis, the presence of manifestations pertaining to organs, the presence of rheumatoid factor, the stage of the disease according to Steinbrocker, or the presence of immune complexes in serum and HLA Dr antigens, which are regarded as fundamental in the pathogenesis of rheumatoid arthritis.