Purpose: This study investigated the association of COPD and postoperative cardiac arrhythmias, specifically supraventricular tachycardia (SVT), as well as mortality in patients undergoing pulmonary resection for non-small cell lung cancer (NSCLC).
Methods: A retrospective chart review of 244 patients who had undergone lung resection for NSCLC at Indiana University Hospital between 1992 and 1997 was undertaken. COPD, which was defined as an FEV(1) of < or = 70% predicted and an FEV(1)/FVC ratio of < or = 70% based on the results of a preoperative pulmonary function test (PFT), was diagnosed in 78 of the 244 patients (COPD group). In the remaining 166 patients, the results of preoperative PFTs did not meet these criteria (non-COPD group). Both groups were otherwise well-matched with respect to multiple variables, including age, comorbid conditions, extent of pulmonary resection, and final pathologic stage. The incidence of cardiac arrhythmias and operative mortality were compared between the two groups using univariate and multivariate analysis.
Results: Seventy-six patients (31.9%) experienced new onsets of postoperative SVT, with 58 of these patients (76.3%) demonstrating atrial fibrillation. The COPD group had a 58.7% incidence of SVT (n = 44) compared to a 27.0% incidence (n = 44) in the non-COPD group (p < 0.0 0 1). Moreover, following initial digoxin therapy, the COPD group required more second-line antiarrhythmic therapy than did the non-COPD group (66.7% vs 37.8%, respectively; p = 0.0 03). Overall, there were 16 operative deaths (6.6%), and the mortality rate was significantly higher in the COPD group (14.1%) than in the non-COPD group (3.0%; p = 0.0 04). Patients who developed SVT had a significantly longer hospital course than did patients who did not (p < 0.0001). Thirteen of the 16 patients who died experienced SVT; however, SVT was not an independent risk factor for death. Finally, of the 19 variables evaluated, major resection (ie, pneumonectomy and bilobectomy) and COPD were identified as independent risk factors for the development of cardiac arrhythmias (p = 0.0 033 and p = 0.0 009, respectively).
Conclusion: Patients with COPD, as defined by the results of preoperative PFTs, are at significantly higher risk for SVT, and in particular SVT refractory to digoxin, following pulmonary resection for NSCLC. Although SVT was not an independent risk factor for death, a significantly longer hospitalization was observed.