Postoperative outcome after coronary artery bypass grafting in chronic obstructive pulmonary disease

BACKGROUND:

It is uncertain if the presence and severity of airflow obstruction in chronic obstructive pulmonary disease (COPD) is predictive of surgical morbidity and mortality after coronary artery bypass grafting (CABG).

METHODS:

Retrospective study of patients who underwent CABG between 1998 and 2003 in a university-affiliated hospital for whom a preoperative spirometry was available. COPD was diagnosed in smokers or ex-smokers 50 years of age or older in the presence of irreversible airflow obstruction. Patients were divided into three groups depending on the spirometry: controls (forced expiratory volume in 1 s FEV₁] 80% or more, FEV₁/forced vital capacity FVC] greater than 0.7), mild to moderate COPD (FEV₁ 50% or more and FEV₁/FVC 0.7 or less) and severe COPD (FEV₁ less than 50% and FEV₁/FVC 0.7 or less).

RESULTS:

Among the 411 files studied, 322 (249 men, 68±8 years of age) were retained (controls, n=101; mild to moderate COPD, n=153; severe COPD, n=68). The mortality rate (3.0%, 2.6% and 0%, respectively) was comparable among the three groups. Patients with severe COPD had a slightly longer hospital stay than controls (mean difference 0.7±1.4 days, P<0.05). Pulmonary infections were more frequent in severe COPD (26.5%) compared with mild to moderate COPD (12.4%) and controls (12.9%), P<0.05. Atrial fibrillation tended to be more frequent in severe COPD than in the other two groups.

CONCLUSION:

Mortality rate associated with CABG surgery is not influenced by the presence and severity of airflow obstruction in patients with COPD. The incidence of pulmonary infections and length of hospital stay were increased in patients with severe COPD.