Bach David S, Goldman Bernard, Verrier Edward, Petracek Michael, Wood Jeremy, Goldman Scott, David Tirone E
Department of Medicine, Division of Cardiology, University of Michigan, Ann Arbor, MI, USA.
J Heart Valve Dis. 2004 Jan;13(1):64-72; discussion 72.
Stentless aortic bioprostheses have excellent hemodynamics. Previous investigations of the Toronto SPV valve described a correlation between the occurrence of significant aortic regurgitation (AR) and dilation of the sinotubular junction. The study aim was to determine the long-term durability and determinants of AR at nine years in a large, multicenter study of the Toronto SPV valve.
The study included 447 patients from six centers. Clinical outcomes and echocardiographic data (gradients, effective orifice area index (EOA-I), left ventricular mass, aortic root dimensions, and presence and severity of AR) were collected prospectively. A multivariable logistic regression model was used to evaluate clinical and echocardiographic variables for impact on the occurrence of AR.
Total follow up was 2,660 patient-years (mean 6.0 +/- 2.5 years; range: 0 to 11.1 years). Mean gradient and EOA-I remained unchanged through nine years. There were 17 cases of structural deterioration, of which 15 underwent explantation. The mechanism of failure was predominantly leaflet tear in the setting of sinotubular dilation. Freedom from explant for structural failure was 90.1% at nine years (100% for patients aged > or = 65 years). Freedom from hemodynamically significant AR was 96.9% at five years and 82.5% at nine years. Determinants of AR were longer duration of follow up, larger valve size, and increase in the ratio of sinotubular junction to the size of valve implanted.
At nine years after implantation of the Toronto SPV valve, hemodynamics remained excellent. There was good freedom from structural deterioration through nine years, and structural failure occurred due to aortic root dilation and leaflet tear, without significant valve calcification. AR tends to occur with longer follow up, larger valve sizes, and dilation of the sinotubular junction.
无支架主动脉生物瓣膜具有出色的血流动力学性能。先前对多伦多SPV瓣膜的研究描述了严重主动脉瓣反流（AR）的发生与窦管交界扩张之间的相关性。本研究的目的是在一项关于多伦多SPV瓣膜的大型多中心研究中，确定9年时AR的长期耐久性和决定因素。
该研究纳入了来自6个中心的447例患者。前瞻性收集临床结局和超声心动图数据（压力阶差、有效瓣口面积指数（EOA-I）、左心室质量、主动脉根部尺寸以及AR的存在和严重程度）。使用多变量逻辑回归模型评估临床和超声心动图变量对AR发生的影响。
总随访时间为2660患者年（平均6.0±2.5年；范围：0至11.1年）。9年间平均压力阶差和EOA-I保持不变。有17例发生结构退化，其中15例接受了瓣膜置换。失败机制主要是在窦管扩张情况下的瓣叶撕裂。9年时因结构失败而进行瓣膜置换的自由度为90.1%（年龄≥65岁的患者为100%）。5年时无血流动力学显著AR的自由度为96.9%，9年时为82.5%。AR的决定因素是随访时间更长、瓣膜尺寸更大以及窦管交界与植入瓣膜尺寸之比增加。
多伦多SPV瓣膜植入9年后，血流动力学仍保持良好。9年间结构退化的自由度良好，结构失败是由于主动脉根部扩张和瓣叶撕裂，无明显瓣膜钙化。随着随访时间延长、瓣膜尺寸增大以及窦管交界扩张，AR倾向于发生。
