Botzenhardt F, Gansera B, Günzinger R, Kemkes B M
Krankenhaus München-Bogenhausen Abt. für Kardiovaskularchirurgie Englschalkinger Str. 77 81925 München, Germany.
Z Kardiol. 2003 May;92(5):407-14. doi: 10.1007/s00392-003-0927-2.
Aim of the study was to evaluate the hemodynamic and clinical performance of the Mosaic bioprosthesis in the aortic position.
The Mosaic bioprosthesis is a stented porcine heart valve for implantation in the aortic and mitral position, which combines zero pressure and root pressure fixation with glutaraldehyde, antimineralization treatment with alpha amino oleic acid (AOA) and a low profile stent, to optimize hemodynamic function and to minimize mechanical wear and thus to achieve longer tissue durability. Included in a multicenter study, 100 patients (49 females) underwent isolated aortic valve replacement with the Mosaic bioprosthesis between February 1994 and May 1999. Average age at implant was 73.4 +/- 7.3 years (range 31.3-86.8 years). Preoperative and operative clinical data are shown in Tables 1 and 2. Patients were followed-up within the first 30 postoperative days, after six months and at annual intervals, including transthoracic echocardiography and documentation of any adverse events. Mean follow-up was 3.8 years (range 0.1-7.1 years), total 383.1 patient-years. Follow-up is 100% complete.
One year after implantation of the bioprosthesis, mean systolic pressure gradient was 15.3 +/- 6.7 mmHg (21), 14.5 +/- 5.7 mmHg (23), 12.7 +/- 4.1 mmHg (25) and 13.0 +/- 4.8 mmHg (27); effective orifice area (EOA) was 1.4 +/- 0.4 cm2 (21), 1.7 +/- 0.4 cm2 (23), 1.8 +/- 0.4 cm2 (25) and 2.6 +/- 0.4 cm2 (27) (Table 3). One year postoperative, nine patients (10.8%) showed mild aortic regurgitation and one patient (1.2%) moderate. Left ventricular mass index decreased significantly for all sizes within the first postoperative year from 159.7 +/- 56.8 g/m2 to 137.3 +/- 40.8 g/m2. Separating the patients with regard to valve size, only the 21-group (154.1 +/- 51.2 g/m2 to 129.1 +/- 34.6 g/m2) and the 27-group (237.7 +/- 59.2 g/m2 to 146.7 +/- 20.6 g/m2) showed significant results. Freedom from event rates at seven years were 96.8 +/- 1.8% for thromboembolic events, 97.2 +/- 2.0% for thrombosed bioprosthesis, 96.6 +/- 2.6% for structural valve deterioration, 98.2% +/- 1.8% for nonstructural dysfunction, 95.9% +/- 2.0% for antithromboembolic hemorrhage, 98.9 +/- 1.1% for endocarditis and 93.9 +/- 3.2% for reoperation and explant (see Table 4). Early mortality (within 30 days) was 3.0%; late mortality was 4.6%/patient-year, including a valve-related mortality of 0.6%/patient-year. Of the patients, 96.5% showed an improvement of at least one NYHA class when comparing preoperative and one year status.
The hemodynamic performance and the frequency of adverse events of the Mosaic bioprosthesis in the aortic position were very satisfactory within the first seven postoperative years with excellent results, comparable to studies about other established bioprostheses and similar to the findings in other Mosaic series. Only the number of cases of antithromboembolic hemorrhage was noticeably high. One reason might be the high percentage of patients under continuous anti-coagulant therapy: Six months postoperative, still 52.2% of the patients received phenprocoumon, 6.7% acetylsalicylic acid. Concerning hemodynamics, patient-prosthesis mismatch appeared to be a common problem, especially in small valve sizes. Separating the sample in groups with EOA index < or = 0.75 cm2/m2 and EOA index > 0.75 cm2/m2 after one year, 51.6% in the 21-group had an EOA index < or = 0.75 cm2/m2, whereas it was 19.4% (23), 18.8% (25) and 0% (27) in the larger size groups. Generally, further data have to be collected to determine durability of the biological tissue, as the critical period has just started with the seventh year of the clinical trial.
The Mosaic bioprosthesis proved to be a reliable and well-functioning device for aortic valve replacement, especially in larger sizes.
本研究的目的是评估主动脉位镶嵌式生物瓣膜的血流动力学及临床性能。
镶嵌式生物瓣膜是一种带支架的猪心脏瓣膜，用于植入主动脉位和二尖瓣位，它将零压力和根部压力固定与戊二醛相结合，采用α-氨基油酸（AOA）进行抗钙化处理，并配备低轮廓支架，以优化血流动力学功能，减少机械磨损，从而实现更长的组织耐久性。在一项多中心研究中，1994年2月至1999年5月期间，100例患者（49例女性）接受了使用镶嵌式生物瓣膜的单纯主动脉瓣置换术。植入时的平均年龄为73.4±7.3岁（范围31.3 - 86.8岁）。术前及手术临床数据见表1和表2。术后前30天、6个月及每年对患者进行随访，包括经胸超声心动图检查及记录任何不良事件。平均随访时间为3.8年（范围0.1 - 7.1年），总计383.1患者年。随访率为100%。
生物瓣膜植入后1年，平均收缩压差为15.3±6.7 mmHg（21号瓣膜）、14.5±5.7 mmHg（23号瓣膜）、12.7±4.1 mmHg（25号瓣膜）和13.0±4.8 mmHg（27号瓣膜）；有效瓣口面积（EOA）为1.4±0.4 cm²（21号瓣膜）、1.7±0.4 cm²（23号瓣膜）、1.8±0.4 cm²（25号瓣膜）和2.6±0.4 cm²（27号瓣膜）（表3）。术后1年，9例患者（10.8%）出现轻度主动脉瓣反流，1例患者（1.2%）出现中度反流。术后第1年内，所有尺寸的左心室质量指数均显著下降，从159.7±56.8 g/m²降至137.3±40.8 g/m²。按瓣膜尺寸对患者进行分组，只有21号瓣膜组（从154.1±51.2 g/m²降至129.1±34.6 g/m²）和27号瓣膜组（从237.7±59.2 g/m²降至146.7±20.6 g/m²）有显著变化。7年无事件发生率为：血栓栓塞事件96.8±1.8%，生物瓣膜血栓形成97.2±2.0%，瓣膜结构恶化96.6±2.6%，非结构功能障碍98.2%±1.8%，抗血栓栓塞性出血95.9%±2.0%，心内膜炎98.9±1.1%，再次手术和瓣膜取出93.9±3.2%（见表4）。早期死亡率（30天内）为3.0%；晚期死亡率为4.6%/患者年，其中瓣膜相关死亡率为0.6%/患者年。与术前相比，96.5%的患者在术后1年时纽约心脏协会（NYHA）心功能分级至少改善了一级。
主动脉位镶嵌式生物瓣膜在术后前7年的血流动力学性能及不良事件发生率非常令人满意，结果优异，与其他已确立的生物瓣膜研究相当，也与其他镶嵌式系列研究结果相似。唯一显著较高的是抗血栓栓塞性出血的病例数。原因之一可能是持续接受抗凝治疗的患者比例较高：术后6个月时，仍有52.2%的患者接受苯丙香豆素治疗，6.7%的患者接受阿司匹林治疗。关于血流动力学，患者-人工瓣膜不匹配似乎是一个常见问题，尤其是在小尺寸瓣膜中。术后1年将样本分为有效瓣口面积指数≤0.75 cm²/m²和＞0.75 cm²/m²两组，21号瓣膜组中有51.6%的患者有效瓣口面积指数≤0.75 cm²/m²，而较大尺寸瓣膜组中这一比例分别为19.4%（23号瓣膜）、18.8%（25号瓣膜）和0%（27号瓣膜）。一般来说，由于临床试验的关键期才刚刚进入第7年，还需要收集更多数据来确定生物组织的耐久性。
镶嵌式生物瓣膜被证明是一种可靠且功能良好的主动脉瓣置换装置，尤其是在较大尺寸时。
