Imaging raises heart disease alarm in COPD
medwireNews: Using cardiac imaging, researchers have found that patients with chronic obstructive pulmonary disease (COPD) have significantly impaired myocardial perfusion reserve (MPR) – a powerful indicator of cardiac risk.
“Altered MPR indicates an early alteration in myocardial tissue and vascular properties in these subjects with COPD,” comment authors Katsuya Onishi (Mie University Graduate School of Medicine, Japan) and colleagues, who say the findings could help clinicians to detect atherosclerosis sooner in COPD patients.
The study involved 20 patients with mild–moderate COPD, 20 age-matched smoking controls, and 20 age-matched non-smoking controls. All participants had normal cardiac imaging results, indicating no regional myocardial ischemia or infarction.
Using stress–rest perfusion cardiovascular magnetic resonance, the authors found that resting myocardial blood perfusion (MBP) was comparable between the three groups.
However, stress MBP was significantly lower in patients with COPD than either control group, resulting in a significantly reduced MPR – the ratio of stress MBP to rest MBP – of 1.76 versus 3.09 and 3.17, respectively.
Among patients with COPD, this equated to a five-fold increased risk for an MPR of less than 1.5, which was shown in a recent study to be associated with a 16-fold increased risk for cardiac death compared with an MPR value of more than 2.0.
And, the researchers report that the increased risk for low MPR in COPD patients was independent of smoking status, after the number of pack–years showed no significant relationship with MPR in multivariate analysis.
Additionally, lower forced expiratory volume in 1 second was significantly associated with reduced MPR. And high levels of C-reactive protein were a significant and powerful predictor of reduced MPR, potentially indicating that systemic inflammation plays an important role in influencing MPR.
Onishi and colleagues conclude that their findings could have important implications for practice.
“The casual detection of COPD should alert the clinician to the potential coexistence of decreased MPR,” they write in the European Heart Journal Cardiovascular Imaging.
“This may represent early stages of atherosclerosis and warrant the evaluation and treatment for [coronary artery disease] as well as assessing the risk for advancing pulmonary disease.”
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013
By Kirsty Oswald, medwireNews Reporter