Elevation of cardiac troponins in exacerbation of chronic obstructive pulmonary disease

Objectives: To investigate the prevalence of serum troponin elevation in patients admitted to hospital with an exacerbation of chronic obstructive pulmonary disease (COPD). Methods: We examined the records of all patients admitted to hospital for treatment of COPD for serum troponin measurement, clinical features of myocardial ischaemia, oxygenation (pulse oximetry, arterial blood gas analysis), spirometry, and duration of admission. Results: Troponin elevation was observed in 58 of 235 (25%) presentations in which troponin was measured. Despite the troponin result, only seven of these 58 patients had been diagnosed with an acute coronary syndrome. New ECG evidence of ischaemia was uncommon. Patients with raised troponins tended to be older (75.7 vs 70.0 years, P = 0.001), had lower pulse oximetry (85.6% vs 89.6%, P = 0.003), were more acidotic (pH 7.34 vs 7.40, P= 0.002) and more hypercapnoeic (pCO₂ 58.0 vs 49.1, P = 0.04). There were no significant differences in serum creatine kinase. Patients with raised troponins had significantly longer admissions (5 vs 3 days, P = 0.001). Conclusions: Serum troponins are commonly raised in acute exacerbations of COPD and appear to reflect the severity of the exacerbation. In the majority of patients there is insufficient evidence to support the diagnosis of an acute coronary syndrome.