Wan Benjamin, Rahnavardi Mohammad, Tian David H, Phan Kevin, Munkholm-Larsen Stine, Bannon Paul G, Yan Tristan D
The Systematic Review Unit, The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia;
The Systematic Review Unit, The Collaborative Research (CORE) Group, Macquarie University, Sydney, Australia; ; Department of Cardiothoracic Surgery, Royal Prince Alfred Hospital, University of Sydney, Sydney, Australia;
Ann Cardiothorac Surg. 2013 Nov;2(6):683-92. doi: 10.3978/j.issn.2225-319X.2013.11.02.
Mitral regurgitation (MR) is the second most common valvular heart disease after aortic stenosis. Without intervention, prognosis is poor in patients with severe symptomatic MR. While surgical repair is recommended for many patients with severe degenerative MR (DMR), as many as 49% of patients do not qualify as they are at high surgical risk. Furthermore, surgical correction for functional MR (FMR) is controversial with suboptimal outcomes and significant perioperative mortality. The percutaneous MitraClip implantation can be seen as a viable option in high surgical risk patients. The purpose of this meta-analysis is to compare the safety, clinical efficacy, and survival outcomes of MitraClip implantation with surgical correction of severe MR.
Six electronic databases were searched for original published studies from January 2000 to August 2013. Two reviewers independently appraised studies, using a standard form, and extracted data on methodology, quality criteria, and outcome measures. All data were extracted and tabulated from the relevant articles' texts, tables, and figures and checked by another reviewer.
Overall 435 publications were identified. After applying selection criteria and removing serial publications with accumulating number of patients or increased length of follow-up, four publications with the most complete dataset were included for quality appraisal and data extraction. There was one randomized controlled trial (RCT) and three prospective observational studies. At baseline, patients in the MitraClip group were significantly older (P=0.01), had significantly lower LVEF (P=0.03) and significantly higher EuroSCORE (P<0.0001). The number of patients with post-procedure residual MR severity >2 was significantly higher in the MitraClip group compared to the surgical group (17.2% vs. 0.4%; P<0.0001). 30-day mortality was not statistically significant (1.7% vs. 3.5%; P=0.54), nor were neurological events (0.85% vs. 1.74%; P=0.43), reoperations for failed MV procedures (2% vs. 1%; P=0.56), NYHA Class III/IV (5.7% vs. 11.3; P=0.42) and mortality at 12 months (7.4% vs. 7.3%; P=0.66).
Despite a higher risk profile in the MitraClip patients compared to surgical intervention, the clinical outcomes were similar although surgery was more effective in reducing MR in the early post procedure period. We conclude the non-inferiority of the MitraClip as a treatment option for severe, symptomatic MR in comparison to conventional valvular surgery.
二尖瓣反流（MR）是仅次于主动脉瓣狭窄的第二常见的心脏瓣膜疾病。若不进行干预，重度有症状的MR患者预后较差。虽然对于许多重度退行性二尖瓣反流（DMR）患者推荐进行手术修复，但多达49%的患者因手术风险高而不符合条件。此外，功能性二尖瓣反流（FMR）的手术矫正存在争议，其结果不理想且围手术期死亡率较高。经皮MitraClip植入术可被视为高手术风险患者的一种可行选择。本荟萃分析的目的是比较MitraClip植入术与重度MR手术矫正的安全性、临床疗效和生存结果。
检索了6个电子数据库，以查找2000年1月至2013年8月发表的原始研究。两名审阅者使用标准表格独立评估研究，并提取有关方法、质量标准和结果指标的数据。所有数据均从相关文章的文本、表格和图表中提取并制成表格，然后由另一名审阅者进行核对。
共识别出435篇出版物。在应用选择标准并剔除患者数量不断累积或随访时间延长的系列出版物后，纳入了4篇数据集最完整的出版物进行质量评估和数据提取。有1项随机对照试验（RCT）和3项前瞻性观察性研究。在基线时，MitraClip组患者年龄显著更大（P = 0.01），左心室射血分数（LVEF）显著更低（P = 0.03），欧洲心脏手术风险评估系统（EuroSCORE）显著更高（P < 0.0001）。与手术组相比，MitraClip组术后残余MR严重程度>2级的患者数量显著更多（17.2% 对0.4%；P < 0.0001）。30天死亡率无统计学差异（1.7% 对3.5%；P = 0.54），神经系统事件也无统计学差异（0.85% 对1.74%；P = 0.43），二尖瓣手术失败后的再次手术率无统计学差异（2% 对1%；P = 0.56），纽约心脏协会（NYHA）心功能III/IV级无统计学差异（5.7% 对11.3；P = 0.42），12个月时的死亡率也无统计学差异（7.4% 对7.3%；P = 0.66）。
尽管与手术干预相比，MitraClip组患者风险更高，但临床结果相似，不过手术在术后早期减少MR方面更有效。我们得出结论，与传统瓣膜手术相比，MitraClip作为重度有症状MR的一种治疗选择具有非劣效性。
