PURPOSE: Inflammatory mediators and therefore postoperative atrial arrhythmias may be reduced after video-assisted thoracic surgical (VATS) lobectomy. Propensity-weighted analysis balances covariates between cohorts and identifies significant differences. It is the most valid method short of a randomized clinical trial to compare outcomes from two clinical treatments.
METHODS: Prospectively collected patients undergoing VATS lobectomy for clinical stage I lung cancer were compared to controls who underwent thoracotomy and lobectomy. Inverse probability of treatment weighted estimators, with weights derived from propensity scores, were used to adjust cohorts for age, gender, preop FEV1, ASA class, and Charlson comorbidity index. Bootstrap methods provided standard errors. Postoperative atrial fibrillation rates were compared.
RESULTS: We analyzed the intraoperative data and postoperative outcomes of 100 patients who underwent lobectomy. Intraoperative conversion to open thoracotomy occurred during 3/37 (8.1%) VATS lobectomies. Operative mortality rate was 1/63 (1.5%) for open cases and 0/37 (0%) for VATS, P = NS. Unadjusted postoperative atrial fibrillation rates were 3/63 (4.7%) after open lobectomy and 4/37 (10.8%) after VATS lobectomy (adjusted rates 4.8% for open lobectomy versus 8.9% for VATS lobectomy)(P=NS). Unadjusted percentage of patients with at least one postoperative complication was 36.6% (open) and 21.6% VATS (p=NS). Unadjusted mean lymph node stations sampled / patient were 4.6 (open) and 4.2 (VATS), p=NS. 16/37 (43.2%) of patients undergoing VATS lobectomy were discharged on postoperative day 2 or 3.
CONCLUSION: Adjusted analysis indicates that postoperative atrial fibrillation rates after VATS lobectomy are not lower than after open lobectomy. Mortality, morbidity, and technique as judged by node removal were similar.
CLINICAL IMPLICATIONS: Postoperative atrial fibrillation rates are not reduced in patients undergoing VATS lobectomy compared to those undergoing thoracotomy and lobectomy. We must continue to be aware of patient risk factors, monitor patients for atrial arrythmias, and seek better methods for preventing postoperative arrythmias.
DISCLOSURE: Walter Scott, None.