Significance of Interstitial Lung Disease on Outcomes Following Cardiac Surgery

Interstitial lung disease (ILD) is a known risk factor for noncardiac surgery due to acute pulmonary exacerbations but its impact after cardiac surgery is not known. We examined perioperative outcomes and risk factors for long-term survival in ILD patients who underwent cardiac surgery. From January 2002 to June 2017, 294 cardiac surgery patients with a previous ILD diagnosis, including 75 patients with idiopathic pulmonary fibrosis (IPF), were identified. A comparison cohort of 1,481 non-ILD patients was selected based on a priori variables. Long-term survival was evaluated using Cox proportional hazard modeling. Median follow-up was 6.4 years. ILD patients had higher postoperative mortality, reintubation rates, longer intensive care unit stay, and higher 30-day readmission rates (all p <0.05). Kaplan-Meier estimates of survival at 1, 5, and 10 years were 89%, 62%, and 37% for the non-IPF ILD cohort, 89%, 50%, and 13% for the IPF cohort, and 95%, 82%, and 67% for the comparison cohort, respectively (overall p <0.001). These significant differences in survival persisted in our risk-adjusted survival analysis. Adjusted survival analysis identified IPF (hazard ratio 3.04) and ILD (non-IPF; hazard ratio 1.78) as significant contributors to all-cause mortality. However, there were no changes in pulmonary function tests after 48 months postprocedure. In conclusion, ILD patients who underwent cardiac surgery have increased operative mortality, reintubation rates, longer intensive care unit, and higher 30-day readmissions compared with non-ILD patients. Moreover, severity of ILD, especially in IPF, appears to be associated with shorter long-term survival. In these patients, pulmonary risk stratification and multidisciplinary team approach are crucial.