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 pO(2) and pCO(2) were lower in patients with SA: pO(2) 80.8 vs. 85 mmHg (P=0.04); pCO(2) 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 pO(2), pCO(2) 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.