Assessment of the incidence of fragmented QRS in electrocardiography in patients with systemic sclerosis and systemic lupus erythematosus

Objective: In systemic sclerosis (SSc) and systemic lupus erythematosus (SLE) cardiac involvement is very com-mon, and it might be asymptomatic. We aimed to assess the presence of fragmented QRS (fQRS) - possible in-dicator of a scar, diffuse damage or conduction system disturbances in those patients.Methods: We examined 74 patients with SSc, 77 with SLE and 40 healthy controls. The incidence of fQRS in ECG was examined according to criteria by Das et al. Disease severity was estimated by Rodnan and SLICCC/ACRDI scores in SSc and SLE respectively. Results: Patients with SSc were slightly older than those with SLE (53 +/- 14 vs 46 +/- 14 yrs), women constituted 91% and 88% of studied groups (p = 0.80). The duration of disease in both groups was similar (p = 0.59). Median of Rodnan and SLICCC/ACR-DI scores were 5 and 4 points, respectively. Left ventricle ejection fraction in both groups was similar (65.5 vs 65.1%, p = 0.51), hypertension incidence was lower in SSc (24 vs 48%, p = 0.004), patients with SLE presented prolonged corrected QT interval (432 vs 424 ms, p = 0.03). Of note, fQRS were observed in 34 (46%) SSc and 29 (38%) SLE patients, p = 0.33. Notched S waves were significantly more frequent in SSc (in 26% vs 10%, p = 0.02). fQRS occurred in 3 (7.5%) of healthy subjects only.Conclusion: The incidence of fQRS is similar in SSc and SLE, but is much more common than in healthy subjects. It is possible that fQRS may be considered an additional marker of heart involvement in these rare diseases.