Arrhythmia finding could enhance COPD management
MedWireNews: Arrhythmias could precede exacerbations in chronic obstructive pulmonary disease (COPD), raising the possibility of a new target for management and treatment, say researchers.
Arrhythmias have previously been associated with COPD but it has not been established whether they are a cause or a consequence of acute exacerbations.
Researchers used electrocardiography to show that P wave dispersion - which increases with arrhythmia - is greater in patients during acute periods of the disease than during stable periods. Furthermore, patients with frequent exacerbations have greater P wave dispersion than those with less frequent episodes.
Surya Bhatt (University of Iowa, USA) and colleagues say that their findings are "supportive of the hypothesis that unrecognized electrical remodeling and arrhythmias lead to, or cause a predisposition to, acute exacerbations of COPD."
The study included 30 COPD patients who had been admitted to hospital for an acute exacerbation. They were followed up for at least a year or until they had another exacerbation. Researchers compared patients' readings at the time of their acute episode with readings taken while they were stable in the 12 months before or after admission.
The authors, reporting in Respiratory Medicine, found that P wave dispersion was an average of 56.7 ms in the acute phase in contrast to 47.7 ms in the stable phase.
Furthermore, in patients who had two or more hospital admissions within a year, P wave dispersion was 52.6 ms, compared with 42.2 ms in patients with less frequent exacerbations; however, this difference did not reach statistical significance.
Regression analysis also showed that increased P wave dispersion shortened the time to readmission by a factor of 1.5.
Prolonged P wave dispersion has been shown to predict the development of paroxysmal atrial fibrillation and to predispose patients to supraventricular arrhythmias.
"Increased dispersion represents inhomogeneous conduction and electrical remodeling. This does not prove but is supportive of our hypothesis that unrecognized electrical remodeling and arrhythmias lead to, or cause a predisposition to, acute exacerbations of COPD," the researchers report.
They conclude that their study "suggests an intriguing possibility that P wave dispersion predates acute exacerbations. This might be a new target for prediction, prevention and therapy of acute exacerbations of COPD."
MedWire (www.medwire-news.md) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2012
By Kirsty Oswald