Supraventricular arrhythmia following lung resection for non-small cell lung cancer and its treatment with amiodarone

Objective: From January 1998 to February 1999, 160 patients undergoing lung resection for non-small cell lung cancer were studied to define factors that increase the risk of postoperative supraventricular arrhythmia (SA) and to assess the effectiveness of amiodarone as an antiarrhythmic drug. Methods: All patients were monitored intraoperatively and postoperatively up to day 3. Onset of SA was documented with ECG. Amiodarone was administered to those who developed SA with a loading dose of 5 mg/kg in 30 min and a maintenance dose of 15 mg/kg in 24 h. Results: Mean age was 64 years (range 27-83 years). There were nine wedge resections, six segmentectomies, 127 lobectomies and 18 pneumonectomies. Twenty-two patients (13%) had SA, all of which were atrial fibrillations. The incidence of supraventricular arrhythmia with pneumonectomy and lobectomy was 33 and 12%, respectively (P = 0.02). None of the patients who had a minor resection developed SA. The peak incidence of onset of SA occurred on postoperative day 2 and lasted from 1 to 12 days (average 3.4 days). Sinus rhythm was achieved with amiodarone in 20 patients (90.9%) with no side effects. Two patients received electrical cardioversion because hemodynamically unstable. Mean preoperative pO₂ and pCO₂ were lower in patients with SA: pO₂ 80.8 vs. 85 mmHg (P = 0.04); pCO₂ 35.5 vs. 38 mmHg (P=0.01). Patients with concomitant cardiopulmonary diseases presented an odds ratio for postoperative arrhythmia of 12.4 (confidence interval 4.5- 34.1) (P <0.0001). Conclusion: Concomitant cardiopulmonary diseases, lower pO₂, pCO₂ and extent of surgery increase the risk of postoperative SA after lung resection for non-small cell lung cancer. Cardiac monitoring in patients at risk is recommended. Amiodarone was both safe and effective in establishing and maintaining sinus rhythm. (C) 2000 Elsevier Science B.V.