Department of Cardiovascular Surgery, Mayo Clinic, Rochester, MN, USA.
Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA.
Eur J Cardiothorac Surg. 2018 Mar 1;53(3):582-589. doi: 10.1093/ejcts/ezx398.
Patients with hypertrophic obstructive cardiomyopathy and basal septal thickness <18 mm are often considered unsuitable candidates for myectomy. Mitral valve (MV) replacement is frequently performed instead. We aimed to determine whether septal thickness affects outcomes and adequacy of myectomy.
Clinical and echocardiographic data were reviewed for 1486 consecutive adult patients with hypertrophic obstructive cardiomyopathy who underwent transaortic septal myectomy from January 2005 through December 2014. Comparisons between patients, grouped by septal thickness (<18 mm, n = 369; 18-21 mm, n = 612 and >21 mm, n = 505), were performed with the Kruskal-Wallis and the Pearson χ2 tests and semiparametric analysis of covariance.
Median group ages were 57, 57 and 54 years (P = 0.007); men comprised 50.4%, 56.7% and 62.0%, respectively (P = 0.003). Intrinsic MV disease was present in 5.9%, 5.2% and 4.6%, respectively (P = 0.80). All patients underwent transaortic septal myectomy. Additional mitral procedures were performed in 7.6%, 7.8% and 8.1%, respectively (P = 0.90). Reasons for MV surgery included intrinsic MV disease (66.7%), residual mitral regurgitation (30.8%) and residual gradient (2.6%). All groups had postoperative gradient relief (median reduction: 51, 54 and 50 mmHg; P = 0.11). Ventricular septal defect occurred in 4 patients (0.3%), and risk did not differ by group (P = 0.24).
Adequate relief of left ventricular outflow tract obstruction can be achieved via transaortic septal myectomy without concomitant MV procedures when septal thickness is < 18 mm, and the risk of ventricular septal defect is minimal. Concomitant MV repair/replacement should be reserved for patients with intrinsic MV disease or inadequate relief of mitral regurgitation/left ventricular outflow tract obstruction following adequate extended septal myectomy.
对于室间隔厚度＜18mm 的肥厚型梗阻性心肌病患者，通常认为其不适合进行心肌切除术。因此，常施行二尖瓣置换术。本研究旨在确定室间隔厚度是否会影响心肌切除术的结果和充分性。
回顾性分析 2005 年 1 月至 2014 年 12 月期间，1486 例接受经主动脉室间隔切除术的成人肥厚型梗阻性心肌病患者的临床和超声心动图数据。通过 Kruskal-Wallis 和 Pearson χ2 检验以及半参数协方差分析，比较按室间隔厚度（＜18mm，n=369；18-21mm，n=612；＞21mm，n=505）分组的患者。
中位年龄分别为 57、57 和 54 岁（P=0.007）；男性比例分别为 50.4%、56.7%和 62.0%（P=0.003）。固有二尖瓣病变的比例分别为 5.9%、5.2%和 4.6%（P=0.80）。所有患者均接受经主动脉室间隔切除术，分别有 7.6%、7.8%和 8.1%的患者接受附加二尖瓣手术（P=0.90）。二尖瓣手术的原因包括固有二尖瓣病变（66.7%）、残余二尖瓣反流（30.8%）和残余梯度（2.6%）。所有组的术后梯度均得到缓解（中位数降幅：51、54 和 50mmHg；P=0.11）。4 例（0.3%）患者发生室间隔缺损，各组间风险无差异（P=0.24）。
当室间隔厚度＜18mm 时，经主动脉室间隔切除术可充分缓解左心室流出道梗阻，且发生室间隔缺损的风险极小。当充分延长室间隔切除后仍存在固有二尖瓣病变或二尖瓣反流/左心室流出道梗阻未充分缓解时，应保留二尖瓣修复/置换术。
