Comparison between video-assisted thoracoscopic thymectomy and transternal thymectomy for myasthenia gravis (analysis of 82 cases)

Video-assisted thoracoscopic surgery (VATS) provides a new approach to thymectomy for myasthenia gravis (MG). We compared the results of video-assisted thoracoscopic thymectomy (VATT) and transternal thymectomy (TT) in Taiwanese people with MG. From January 1997 to August 2002, we enrolled a total of 82 patients with MG who underwent TT and anterior mediastinal adipose tissue removal in our study. Of those, 51 patients underwent VATT, and 31 patients underwent TT. The men-to-women ratios were 18:33 and 15:16 in the VATT and TT groups, respectively. The mean age was 37.9 ± 17.56 years in the VATT group and 35.6 ± 16.8 years in the TT group (P = 0.55). Preoperative Osserman's classification revealed the following: class I: 11 (21.6%), 13 (41.9%); class IIA: 18 (35.3%), 11 (35.5%); class IIB: 18 (35.3%), 5 (16.1%); class III: 2 (3.9%), 0; and class IV: 2 (3.9%), 2 (6.5%), respectively, in the two groups (P = 0.06). During VATT, all but two patients were placed supine in the 45° left lateral decubitus position under double-lumen intubated anesthesia. Usually three 1-cm incision wounds over anterior axillary line at the third, fifth, and sixth intercostal spaces were necessary. A total of 82 patients (51 with VATT and 31 with TT) were studied. There were no statistical differences between the two groups of patients in terms of sex, age, and severity of MG. In VATT and TT groups, postoperative hospital stays were 6.1 ± 3.3 and 26.9 ± 14.1 days, respectively (P = 0.001). Intensive care unit stays were 1.5 ± 1.1 and 3.2 ± 2.3 days, respectively (P = 0.018). Operative times were 180.0 ± 53.4 and 248.2 ± 71.9 minutes, respectively (P = 0.004). Thymus weights were 43.7 ± 22.5 and 52.2 ± 29.6 g, respectively (P = 0.141). Fifty-one VATT procedures were performed through a right-side approach without conversion. Most patients were extubated in the operating room or recovery room. The harvested thymus glands had an average weight of 49.4 g (range, 21.4-90 g). There were no surgical mortality cases. There was no statistically significant difference (P = 0.574) in the post-operative improvement classification between the two groups, with a mean of 4 years of follow-up. In the VATT group, 14 (27.5%) patients had complete remission without any medication, 14 (27.5%) patients were in class II, 21 (41.1%) patients were in class III, 2 (3.9%) patients were in class IV, and 0 (0%) patients were in class V, according to postoperative classification of DeFilippi et al.⁴ We concluded that VATT is technically feasible and safe and is associated with a favorable postoperative outcome compared with the transsternal approach.