Under-use of beta-blockers in patients with ischaemic heart disease and concomitant chronic obstructive pulmonary disease

Abstract
Background: Beta-blockers (BB) improve morbidity and mortality in ischaemic heart disease. There is a general reluctance to use BB, especially in patients with chronic obstructive pulmonary disease (COPD), which is perceived as an absolute contraindication. As large numbers of patients are labelled with COPD without objective evidence, they may miss out on the benefit from these drugs. Aim: To assess the use of BB in patients with COPD admitted with acute coronary syndrome (ACS), and to assess the supporting evidence for the diagnosis of COPD in these patients. Method: Case-note review and retrospective analysis of 457 consecutive patients admitted with troponin-positive ACS between October 2002 and October 2003. Results: Of 457 ACS patients studied, 246 (54%) were discharged on a BB. Cardiologists prescribed BB in ACS patients more frequently than did general physicians, (70% vs. 30%, respectively). The reasons for withholding BB were: not documented 27%, COPD 33%, heart failure 24%, others 16%. Ninety-four patients (21%) had a diagnosis of COPD; only 58 (62%) of these had been reviewed by a chest physician or had previous pulmonary function tests. Of the 94 patients with COPD, only 15 (16%) were prescribed BB during the admission: 9 by cardiologists and 6 by non-cardiologists. BB were discontinued in two patients due to an increase in dyspnoea. Conclusion: Many patients with a diagnosis of COPD have no objective evidence to support the diagnosis and are denied the prognostic benefits of BB when presenting with ACS. Before withholding beta-blockers, COPD and reversibility should be ascertained by pulmonary function testing. The overall use of beta-blockers remains sub-optimal and could be improved in this setting.