Role of signal-averaged electrocardiography and ventricular late potentials in patients with chronic obstructive pulmonary disease

Abstract

Patients with chronic obstructive pulmonary disease (COPD) have an increased risk for cardiac arrhythmias. Ventricular late potentials (VLP) on signal-averaged electrocardiography (SAECG) are associated with an increased risk for malignant ventricular arrhythmias. Our aim is to investigate the modifications of SAECG parameters and the presence of VLP as possible indicators of proarrhythmic substrate in patients with COPD. We prospectively enrolled 41 consecutive patients in the COPD group and 63 patients without any history of pulmonary disease, matched for age and hypertension history, in the control group. Pulmonary function tests, arterial blood gases, echocardiography, 24-hour Holter monitoring and SAECG were performed. We measured total filtered QRS duration (QRSf), duration of high frequency, low-amplitude signals < 40 V (HFLA40), and root mean square voltage in the last 40 ms (RMS40). VLP were considered if at least two of these parameters were abnormal. Results. We did not register any significant differences in QRSf, HFLA40 or RMS40 between the two groups. In the COPD group there was a non-significant higher percentage of patients with VLP in comparison with the control group. In the COPD patients we registered a significantly higher number of isolated premature ventricular beats and of combined complex ventricular arrhythmias, consisting of polymorphic PVC, couplets, triplets or nonsustained ventricular tachycardias. None of these arrhythmic parameters correlated with SAECG variables or with the presence of VLP. Conclusion. In COPD patients parameters measured on signal-averaged electrocardiography and ventricular late potentials analysis have little value in risk stratification for ventricular arrhythmias.

Signal-Averaged ECG: Basics to Current Issues

“…Yildiz et al [33] reported a signiicantly increased total QRS duration in patients with COPD compared to control subjects and LVPs but no signiicant association with premature ventricular contractions. Despite higher prevalence of LVPs, premature ventricular contractions, and complex ventricular arrhythmias in patients with COPD compared to healthy controls, SAECG had litle value in stratiication of ventricular arrhythmia risk in a study including 41 patients with COPD and 63 patients without any history of pulmonary disease [27]. …”

“…The association between LVPs and rejection of heart transplant is explained by occurrence of areas of myocardial ibrosis, due to cell changes caused by alloreactive T lymphocytes against graft antigens and ischemia-reperfusion injuries as soon as the blood low is reestablished [22]. 20 young heart transplant patients SAECG is not efective in detecting heart transplant rejection in young patients Horenstein et al [21] Extracardiac disorders were also associated with LVPs, especially hypertension, metabolic syndrome, obesity, eating disorders, diabetes mellitus, renal failure, chronic obstructive pulmonary disease (COPD), acromegaly, thalassemia, connective tissue diseases, epilepsy, and schizophrenia [6,[23][24][25][26][27]. Antiarrhythmic therapy, thrombolytic drugs, statins, steroids, and coronary interventions may inluence LVPs [6].…”

Ventricular late potential in cardiac syndrome X compared to coronary artery disease

“…QRS duration > 120 ms, RMS40 > 38 ms and LAS40 < 20 μV were considered abnormal [24]. Presence of two or more abnormal SAECG measurements was considered indicative of VLP [24, 25]. …”