Long-term survival of patients with pulmonary disease undergoing coronary artery bypass surgery

Abstract

Objectives: We sought to investigate the long-term survival of patients with obstructive, restrictive and chronic obstructive pulmonary disease (COPD) as defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD).

Methods: A prospective database was retrospectively analysed and cross-correlated with the UK strategic tracking service to evaluate survival after primary coronary artery bypass grafts (CABG). Univariate and multivariate Cox regression analyses were performed. Three separate multivariate analyses were performed: COPD GOLD criteria for obstructive and/or restrictive lung disease, forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and the FEV1/FVC ratio to investigate the effect of FEV1 and FVC individually.

Results: We analysed 13 337 primary CABG procedures. The median follow-up was 7 years. Univariate analysis demonstrated that obstructive (P < 0.0001), restrictive (P < 0.0001) and mixed obstructive and restrictive pulmonary disease (P < 0.0001), and COPD as defined by the GOLD criteria (P < 0.0001), are all significant factors determining long-term survival. Cox regression analysis identified age, diabetes, moderate LV, poor LV, peripheral vascular disease, dialysis, left internal mammary artery (LIMA) usage, EuroSCORE, cardiopulmonary bypass and creatinine kinase muscle-brain isoenzyme as significant factors in addition to pulmonary disease that determine long-term survival. Moderate and severe COPD defined by GOLD criteria were significant factors determining long-term survival, but mild COPD had no significant effect. Obstructive and restrictive lung disease were both significant factors determining long-term survival. Restrictive lung disease, however, carried a greater prognostic significance (higher hazard ratio 2.2 vs 1.6) than obstructive. LIMA utilization in patients with COPD was not associated with an increased intensive care unit stay, re-intubation rate or in-hospital mortality rate.

Conclusions: Pulmonary disease is a significant factor determining long-term survival. Patients with severe COPD still have a relatively good long-term survival and should not be denied surgery. LIMA utilization in patients with COPD results in a significantly increased long-term survival, without an increased intensive care unit stay, re-intubation rate or in-hospital mortality rate.