Assessment of cardiac arrhythmias, P wave and QT dispersion in systemic sclerosis

Abstract

Cardiac involvement in systemic sclerosis (SSc) is significant cause of SSc-related mortality. The objective of the study was to assess cardiac arrhythmias, P wave and QT dispersion in SSc patients. 40 SSc patients and 40 healthy participants who had similar sociodemographic characteristics with the patients were enrolled in the study. P wave dispersion (Pd), QT dispersion (QTd), and corrected QT (QTc) dispersion (QTcd) were calculated by measuring maximum (max) and minimum (min) of P wave, QT interval, QTc in 12-leads electrocardiography (ECG). Cardiac arrhythmias and conduction disorders were assessed by ECG and Holter-ECG. The mean age of SSc patients (92.5% of females) was 50.9±13.9 years similar with the healthy group (51.4±8.9). Abnormal ECG findings were found in 27.5% of SSc patients and remarkably higher in comparison to the healthy participants (p=0.019). The most frequently reported abnormal ECG findings were left anterior fascicular block (15%), ventricular premature beat (10%) and first-degree atrioventricular heart block (5%). The comparison of dispersion showed no statistically important difference in Pd between two groups (p=0.69) while QTd, QTc, QTcd, QTc min, and QTc max were markedly prolonged in patients with SSc (p=0.039; p<0.001; p=0.021; p<0.001; p<0.001, respectively). The assessment of Holter-ECG demonstrated that supraventricular tachycardia was frequently detected in patients with SSc (22.5% vs 2.5%; p=0.007). This study indicated a significantly elevated incidence of abnormal ECG results and SVT, an arrhythmia not typically identifiable through standard ECG but detectable via Holter monitoring, in patients with SSc. In the study, QTd, QTc, and QTcd intervals were significantly longer in SSc patients, which may indicate a susceptibility to arrhythmias.