Thoracoscopic completion thymectomy in refractory nonthymomatous myasthenia

Background. The aim of this study was to assess the efficacy of thoracoscopic completion thymectomy in patients with refractory nonthymomatous myasthenia. Methods. Eight patients were operated upon after transcervical (n = 6) or transsternal (n = 2) thymectomy. The mean interval between operations was 129 months. Every patient was completely disabled despite treatment with large dosages of prednisone in combination with pyridostigmine (n = 5) or azathioprine (n = 3) and with repeated plasma exchanges. Results. Gross (n = 5) or microscopic (n = 3) residual thymic tissue was found in all patients. There was no mortality, but morbidity included 2 patients with postoperative myasthenic crisis requiring reintubation and mechanical ventilation. The mean hospital stay was 4.75 days. The mean follow-up was 28.3 months. At the last follow-up, 6 patients had achieved symptomatic improvement as expressed by significant change in mean Osserman class (3.37 versus 2.12, p = 0.03), and prednisone dosage (43 versus 20 mg/d, p = 0.03). Conversely, there was no difference in dosage of pyridostigmine and azathioprine or in number of exchange cycles. Conclusions. Our results suggest that thoracoscopic completion thymectomy may be beneficial for selected patients with refractory nonthymomatous myasthenia. (Ann Thorac Surg 2000;70:918-23)