Braxton J H, Higgins R S, Schwann T A, Sanchez J A, Dewar M L, Kopf G S, Hammond G L, Letsou G V, Elefteriades J A
Section of Cardiothoracic Surgery, Yale University School of Medicine, New Haven, CT 06510, USA.
J Heart Valve Dis. 1996 Mar;5(2):169-73.
Reoperative mitral surgery via sternotomy can be associated with significant complications, including excessive blood loss and injuries to the heart, great vessels and patent coronary artery grafts. The right antero-lateral thoracotomy offers excellent exposure with less risk from re-entry.
Between 1982 and 1992, 221 patients had repeat mitral valve procedures at our institution. Fifteen of these 221 underwent mitral valve replacement via right thoracotomy. Indications for surgery in each group included bioprosthetic valve failure, paravalvular leak and bacterial endocarditis. Fifteen patients having reoperative mitral valve surgery via right thoracotomy approach were compared with a control group of 33 patient who underwent surgery via repeat sternotomy. All thoracotomy patients underwent mitral replacement or repair with ventricular fibrillation without aortic cross-clamping. Operative time, cardiopulmonary bypass time, requirement for inotropic support, blood loss within the first six postoperative hours, number of blood units transfused, length of ICU stay, days to discharge, and 30-day survival were compared between the two groups. In addition, the preoperative PaO2/FiO2 (P/F) ratio was evaluated as a prognostic indicator.
Bypass time (162 +/- 43 min thoracotomy group vs. 131 +/- 34 min sternotomy group), operative time (389 +/- 100 min thoracotomy group vs. 450 +/- 25 min sternotomy group), ICU stay (6 +/- 8 days thoracotomy group vs. 5 +/- 6 days sternotomy group), P/F ratio (352 +/- 142 thoracotomy group vs. 423 +/- 108 sternotomy group), and 30-day survival (93% thoracotomy group vs. 91% sternotomy group) were not found to be significantly different between groups. Of great significance was the reduction in blood loss (277 +/- 152 ml thoracotomy vs. 651 +/- 504 ml sternotomy, p < 0.05) and blood transfused (2.0 +/- 1.7 units thoracotomy vs. 6.5 +/- 3.3 units sternotomy, p < 0.01) with the thoracotomy approach. Also of significance was a reduction in frequency with which significant inotropic support was needed to separate from cardiopulmonary bypass (26% vs. 63%, p < 0.05). Despite decreased access to the heart for de-airing maneuvers, no cerebrovascular events whatsoever were noted with the thoracotomy approach.
The right thoracotomy approach is recommended for redo mitral valve surgery. Despite these advantages, severe pulmonary dysfunction (as indicated by a P/F ratio less than 300) correlated with a prolonged hospital course in four thoracotomy patients; such patients should have repeat sternotomy.
经胸骨切开术进行再次二尖瓣手术可能会引发严重并发症，包括失血过多以及对心脏、大血管和冠状动脉搭桥血管的损伤。右前外侧开胸术能提供良好的视野，再次开胸风险较低。
1982年至1992年间，我院有221例患者接受了再次二尖瓣手术。这221例患者中有15例通过右胸切开术进行二尖瓣置换。每组的手术适应症包括生物瓣膜功能衰竭、瓣周漏和细菌性心内膜炎。将15例通过右胸切开术进行再次二尖瓣手术的患者与33例通过再次胸骨切开术进行手术的对照组患者进行比较。所有开胸患者均在无主动脉交叉阻断的情况下，在心室颤动状态下进行二尖瓣置换或修复。比较两组患者的手术时间、体外循环时间、血管活性药物支持需求、术后首6小时内失血量、输血量、重症监护病房（ICU）住院时间、出院天数和30天生存率。此外，术前动脉血氧分压/吸入氧分数（P/F）比值被评估为一项预后指标。
两组间的体外循环时间（开胸术组162±43分钟，胸骨切开术组131±34分钟）、手术时间（开胸术组389±100分钟，胸骨切开术组450±25分钟）、ICU住院时间（开胸术组6±8天，胸骨切开术组5±6天）、P/F比值（开胸术组352±142，胸骨切开术组423±108）和30天生存率（开胸术组93%，胸骨切开术组91%）差异均无统计学意义。具有重要意义的是，开胸术组的失血量（277±152毫升，胸骨切开术组651±504毫升，p<0.05）和输血量（开胸术组2.0±1.7单位，胸骨切开术组6.5±3.3单位，p<0.01）减少。同样具有重要意义的是，开胸术组在脱离体外循环时需要显著血管活性药物支持的频率降低（26%对63%，p<0.05）。尽管开胸术组心脏排气操作的入路减少，但未发现任何脑血管事件。
建议采用右胸切开术进行再次二尖瓣手术。尽管有这些优点，但4例开胸术患者中出现严重肺功能障碍（以P/F比值低于300为指标）与住院时间延长相关；此类患者应采用再次胸骨切开术。
