Borghetti V, Campana M, Scotti C, Domenighini D, Totaro P, Coletti G, Pagani M, Lorusso R
II Cardiac Surgery Division, Civil Hospital, Piazzale Spedali Civili n degrees 1, 25125, Brescia, Italy.
Eur J Cardiothorac Surg. 2000 Apr;17(4):431-9. doi: 10.1016/s1010-7940(00)00344-4.
The effects of different annuloplasty rings on mitral annulus dynamics and left-ventricular (LV) function after mitral-valve repair (MVR) are still controversial. This study sought to compare biological versus prosthetic rigid rings for annular remodelling in MVR at long term.
Forty-four consecutive patients were retrospectively enrolled. All patients had isolated posterior-leaflet prolapse and underwent identical surgical mitral-valve reconstruction (quadrangular resection of the posterior leaflet associated with annuloplasty). Twenty-three patients underwent mitral annuloplasty with an autologous pericardial ring (group I), whereas 21 patients had MVR with a Carpentier-Edwards rigid ring (group II). No differences existed between the groups in terms of pre-operative patient profile. Post-operative LV systolic indices have been assessed by two-dimensional echocardiography at rest and during supine bicycle exercise. Mitral annular motion has been examined by means of the extent of mitral annulus systolic excursion (MASE), as measured in four longitudinal LV segments (anterior, inferior, septal and lateral). Mean and peak trans-mitral flow velocities (TMFV) have been also evaluated by continuous-wave Doppler.
The mean follow-up did not differ between the groups, those being 41+/-12 months in group I (range17-65 months) and 46+/-15 months in group II (range 23-83 months), respectively. Post-operative echocardiographic study did not show significant mitral regurgitation at rest or at peak exercise in any patient. ANOVA analysis for repeated measures showed a significant interaction in peak TMFV (F((1,42))=5.23; P=0.03), and in left-ventricular ejection fraction (LVEF; F((1,42))=7.61, P=0.01). The analysis of contrasts showed a significant increase in TMFV in both groups (group I from 1.22+/-0.22 to 1.79+/-0.32 m/s, t=-8.8, P<0.0001; and group II from 1.19+/-0.17 to 1.96+/-0.33 m/s, t=-12.8, P<0.0001). Recruitment of LVEF reserve during exercise was observed only in group I (from 59.5+/-6 to 65.8+/-6%, t=-3.95, P<0.005), whereas no substantial change occurred in LV performance in group II. A trend towards better MASE at all the studied longitudinal segments at rest and during exercise was observed in group I. No minor or major calcifications have been observed on pericardial rings.
The autologous pericardium seems to be superior to rigid prosthetic rings for annuloplasty in MVR since it provides more favourable mitral annulus dynamics and preserves LV function during stress conditions. Effective and durable annular remodelling with the autologous pericardium is achieved up to 6 years from surgery, with no echocardiographic sign of degeneration in the long term. Further studies are required to compare biological versus flexible prosthetic rings in MVR.
不同瓣环成形环对二尖瓣修复术（MVR）后二尖瓣环动力学及左心室（LV）功能的影响仍存在争议。本研究旨在长期比较生物瓣环成形环与人工硬瓣环在MVR中对瓣环重塑的效果。
回顾性纳入44例连续患者。所有患者均为单纯后叶脱垂，并接受相同的二尖瓣手术重建（后叶四边形切除联合瓣环成形术）。23例患者采用自体心包环进行二尖瓣瓣环成形术（I组），而21例患者采用Carpentier-Edwards硬瓣环进行MVR（II组）。两组患者术前资料无差异。术后通过二维超声心动图在静息及仰卧位踏车运动时评估LV收缩指标。通过测量左心室四个纵向节段（前壁、下壁、间隔和侧壁）的二尖瓣环收缩期位移（MASE）来检查二尖瓣环运动。还通过连续波多普勒评估平均和峰值跨二尖瓣血流速度（TMFV）。
两组患者的平均随访时间无差异，I组为41±12个月（范围17 - 65个月），II组为46±15个月（范围23 - 83个月）。术后超声心动图检查未显示任何患者在静息或运动峰值时有明显二尖瓣反流。重复测量的方差分析显示，峰值TMFV（F((1,42)) = 5.23；P = 0.03）和左心室射血分数（LVEF；F((1,42)) = 7.61，P = 0.01）存在显著交互作用。对比分析显示两组TMFV均显著增加（I组从1.22±0.22 m/s增至1.79±0.32 m/s，t = -8.8，P < 0.0001；II组从1.19±0.17 m/s增至1.96±0.33 m/s，t = -12.8，P < 0.0001）。仅在I组观察到运动期间LVEF储备的恢复（从59.5±6%增至65.8±6%，t = -3.95，P < 0.005），而II组LV功能无实质性变化。I组在静息和运动时所有研究的纵向节段均有MASE改善的趋势。心包环上未观察到轻微或严重钙化。
自体心包在MVR瓣环成形术中似乎优于人工硬瓣环，因为它能提供更有利的二尖瓣环动力学，并在应激状态下保留LV功能。自体心包可实现有效且持久的瓣环重塑，术后长达6年，长期超声心动图检查无退变迹象。需要进一步研究比较MVR中生物瓣环与柔性人工瓣环。
