Author + information
- Uğur Nadir Karakulak1,
- Naresh Maharjan1,
- Elifcan Aladağ2,
- Levent Kılıç2,
- Ali Akdoğan2,
- Ergün Barış Kaya1 and
- Lale Tokgözoğlu1
Scleroderma is a chronic, autoimmune disease that leads to fibrosis of the skin and visceral organs. Tp-e/QTc ratio, that reveals transmural repolarization and arrhythmogenesis, is a new, highly reliable parameter, that can be used to determine individuals with a high risk of ventricular arrhythmias. In this study, Tp-eQTc ratio was calculated in scleroderma patients with and without pulmonary hypertension and the difference between the two groups as well as the relation of this parameter with mortality was sought for.
A total of 160 scleroderma patients were includes in this study. From the 12-derivation ECG of each patient, the interval between the peak (Tp) and the end of the T wave (Te) was calculated and the difference was used to obtain a ratio with QTc. Independent t-test was used to determine difference between groups while Cox regression analysis was used to determine its significance as a predictor of mortality.
Pulmonary hypertension was present in 15% of the patients. The Tp-e/QTc ratio in scleroderma patients without pulmonary hypertension was 28.3±4.9 and that in patients with pulmonary hypertension was 31.4±5.7. The difference between the two groups was statistically significant (p=0.007). This ratio was found to be a predictor of mortality in those with pulmonary hypertension (p=0.029) but it did not predict mortality in those without pulmonary hypertension (p=0.489). The risk of mortality was found to be increased in patients with a Tp-e/QTc ratio > 0.35 as compared to those with a ratio of <0.35 (Fig. 1).
Non-invasive methods of determining arrhythmia risk has been receiving increased attention in recent years. Tp-e/QTc ratio is a new parameter that predicts arrhythmia risk in different spectrum of diseases. In this study, presence of pulmonary hypertension in scleroderma patients was found to be a risk factor for cardiac arrhythmias and a significant correlation was found between this simple and easy ECG parameter and mortality. Patients with a high Tp-e/QTc ratio must be closely and carefully followed-up for cardiac complications.