Abnormal spatial QRS-T angle, a marker of ventricular repolarisation, predicts serious ventricular arrhythmia in systemic sclerosis
E. Gialafos, P. Konstantopoulou, C. Voulgari, I. Giavri, S. Panopoulos, G. Vaiopoulos, M. Mavrikakis, I. Moyssakis, P. Sfikakis
First Department of Propaedeutic and Internal Medicine, Athens University Medical School, Athens, Greece. gialaf@yahoo.com
CER4816 
Full Paper
Abstract
OBJECTIVES:
Cardiac involvement may be under-diagnosed in asymptomatic patients with systemic sclerosis (SSc). Standard electrocardiography-derived spatial QRS-T angle (spQRS-Ta) is an established marker of ventricular repolarisation heterogeneity, and a strong independent predictor of cardiac morbidity and mortality, including sudden death, in the general population. We examined whether spQRS-Ta is abnormal in asymptomatic SSc patients and assessed its predictive value for possibly concurrent, serious ventricular arrhythmia.
METHODS:
SpQRS-Ta and 24-hour Holter recordings were obtained from 69 SSc patients (aged 51±13 years, 63 women) without clinically evident cardiac involvement and having left ventricular ejection fraction at least 50% by echocardiography. `Healthy` subjects matched 1:1 with patients for age, gender and body mass index served as controls.
RESULTS:
SpQRS-Ta was wider in SSc (median value 15.6°, interquartile range 10.6–24.3°) than controls (10.5°, 7.3–13.5°, p=0.0001) and not associated with skin fibrosis extent or specific clinical manifestations and autoantibodies. Twenty-four-hour Holter recordings revealed couplets of ventricular beats in six (Lown class IVa) and non-sustained ventricular tachycardia in five patients (Lown class IVb); spQRS-Ta was wider in those eleven patients with serious ventricular arrhythmia than the remaining patients (24.9°, 14.9–31.3° vs. 14.4°, 9.6–22.3°; p=0.02). A spQRS-Ta>19.3° demonstrated 80% sensitivity and 68% specificity (area under the curve 0.81, p=0.02) to predict the presence of non-sustained ventricular tachycardia in Holter monitoring.
CONCLUSIONS:
Ventricular repolarisation heterogeneity, as reflected by wider spQRS-Ta, is common in SSc. Increased spQRS-Ta could serve as a simple screening test for further investigation to identify patients at risk or prone to develop life-threatening ventricular arrhythmia.
PMID: 22510222 [PubMed]
Received: 09/06/2011 - Accepted : 26/10/2011 - In Press: 25/06/2012 - Published: 25/06/2012
