Introduction: Cardiac involvement in patients with systemic sclerosis represents an important cause of morbidity and mortality. Electrocardiographic abnormal findings are identified in 25-75% of SSc patients, being considered an independent predictor of mortality. In SSc, even without cardiac symptoms, QT and corrected QT (QTc) intervals appear prolonged, which can lead to life-threatening tachyarrhythmias. The aim of this study was to assess the QTc interval in SSc patients, and, on the other hand, the correlations between QTc and nailfold capillary findings in these patients.

Material and methods: This case control study was performed on a group of 22 patients with SSc, who fulfilled the 2013 ACR/EULAR Classification Criteria for Systemic Sclerosis and 22 healthy subjects, matched for age and gender, as controls. In all the SSc patients and controls were performed: 12-lead standard electrocardiographic recordings and nailfold capillaroscopy. QTc interval and nailfold capillaries density were recorded in SSc patients and controls. In SSc were determined: antinuclear antibodies, anti-topoisomerase I, anti-centromere and anti-RNA polymerase III antibodies, too. Data are presented as mean ± standard deviation. Statistical analyses were performed using the Student’s t-test, ANOVA test, and the Pearson’s correlation. Differences were considered statistically significant at the value of p < 0.05.

Results: The values of QTc interval were prolonged in SSc group than in controls (p<0.01). These values of QTc interval increased with the severity of the nailfold capillaroscopic pattern, the differences having statistical significance (p<0.001). It was demonstrated a statistically significant negative correlation between the values of QTc intervals and nailfold capillaries density, this correlation being stronger with the increase of the severity of nailfold capillaroscopic pattern.

Conclusion: SSc patients present prolonged QTc interval, even they are without any cardiac symptoms, requiring the ambulatory 24-hour ECG monitoring in order to identify ventricular arrhythmias and initiate appropriate therapy

Keywords: Corrected QT interval; Nailfold capillaroscopy; Systemic sclerosis