Reliability of symptoms suggestive of angina in patients with chronic obstructive pulmonary disease.

BACKGROUND Due to overlapping symptoms and inadequate exercise capacity, noninvasive diagnosis of coronary artery disease (CAD) may be under- or overestimated in patients with chronic obstructive pulmonary disease (COPD). OBJECTIVE To assess outcomes of coronary angiography in COPD patients depending on baseline clinical characteristics. METHODS Medical records of 157 patients with COPD and 157 patients without COPD matched for baseline clinical characteristics who had undergone diagnostic coronary angiography for the first time were reviewed retrospectively. RESULTS The frequency of significant CAD was significantly lower in COPD patients than in the control group (52.8% vs. 80.2%, p<0.001). Frequencies of CAD risk factors (older age, hypertension, diabetes, smoking history) were significantly more frequent among COPD patients having significant CAD. Among patients reporting stable angina pectoris, significant CAD was detected in 32.7% of COPD patients and 71.0% of non-COPD patients (p<0.001). However, among the patients with a diagnosis of unstable angina pectoris, significant CAD was detected in 87.5% of COPD patients and 90.2% of non-COPD patients (p=0.755). CONCLUSION Diagnosis of CAD in COPD patients by symptomatology may be difficult. However, clinical diagnosis of CAD in the setting of unstable angina is accurate in most of the COPD patients. Therefore, further noninvasive diagnostic methods or careful follow up may be more appropriate for COPD patients reporting stable angina pectoris.