Generation of chordae tendineae with polytetrafluoroethylene stents. Results of mitral valve chordal replacement in sheep

Surgical repair of ruptured or elongated chordae tendineae of the mitral valve is one of the most complex reconstructive techniques in cardiac surgery. Various surgical procedures have been described to repair chordal abnormalities of the anterior leaflet of the mitral valve with unpredictable results. Mitral valve replacement is usually recommended in that situation. This report describes a simple repair technique that we have devised. We resected one or two marginal chordae of the anterior leaflet of the mitral valve in 35 sheep and replaced them with a double-armed, pledget-supported, expanded polytetrafluoroethylene suture. The 30 surviving animals were studied hemodynamically and were electively put to death 3, 6, 9, 18, and 24 months after the operation. Mitral insufficiency did not develop in any of the sheep. All specimens had a normal mitral valve without thrombosis. The polytetrafluoroethylene suture remained pliable and was incorporated into the anterior leaflet and papillary muscle. Scanning and transmission electron microscopy showed that the suture was completely covered by a sheath of tissue with a collagen structure remarkably similar to that of a native chorda. Calcification was not detected in the new chordae. This reproducible and safe technique may considerably simplify the difficult repair of chordal abnormalities.     

Replacement of Chordae Tendineae with Expanded Polytetrafluoroethylene Sutures

One or more primary chordae tendineae of the anterior leaflet of the mitral valve was replaced with expanded polytetrafluoroethylene (PTFE) sutures in 22 patients as part of mitral valve reconstructive procedure. One patient with flail anterior leaflet of the tricuspid valve also had replacement of chordae tendineae with a PTFE suture. These patients have been followed from 2 to 48 months, mean of 17 months. Valve function has been assessed annually by Doppler echocardiography. The PTFE chordae cannot be visualized by two- dimensional echocardiography but they seem to allow the leaflet to move normally during the cardiac cycle. The function of the repaired valve in these 23 patients has remained most satisfactory during the observed interval. We believe that PTFE sutures can be used safely to replace diseased chordae tendineae of the mitral and tricuspid valves when conventional techniques of chordal repair are not possible.     

Replacement of Mitral Valve Posterior Chordae Tendineae with Expanded Polytetrafluoroethylene Suture: A Finite Element Study

A bstract Background and Aims : Expanded polytetrafluoroethylene (ePTFE) suture has been used clinically for replacement of ruptured mitral valve chordae tendineae. The purpose of this study was to assess mitral valve function after posterior chordal replacement with ePTFE suture. Methods : A three-dimensional finite element computer model of the mitral valve was used, which incorporated geometry, regional tissue thickness, collagen fiber orientation, and anisotropic material properties for the leaflets, interface, and chordae tendineae. To simulate chordal rupture, four marginal and four basal chordae were removed from the posterior leaflet. Chordal replacement was simulated using two elements with the physical and material properties of 2–0 ePTFE suture. Systolic loading pressures were applied. Results : The chordal rupture model demonstrated posterior leaflet prolapse, abnormal stress concentrations, potential regurgitation, and elevated chordal stress. Conversely, the chordal replacement model corrected the prolapse and returned chordal stress to normal levels. However, stress concentrations were shown at suture attachment points. Conclusions : This integrated mitral valve finite element model provides a tool to investigate the performance of the valve system. In this study, we have shown that 2–0 ePTFE suture replacement of ruptured posterior chordae tendineae returns the valve to a near normal state, in terms of leaflet stress and coaptation, and chordal stresses.     

Comparison of Viscoelastic Properties of Suture Versus Porcine Mitral Valve Chordae Tendineae

Recent reports have advocated the use of polytetrafluoroethylene (PTFE) suture for replacement or reinforcement of ruptured or elongated mitral valve chordae tendineae. The mechanical properties of PTFE (Gore-Tex) and other sutures were determined and compared to those of porcine mitral valve chordae. The results were analyzed to assess how closely chordal mechanical function may be simulated by synthetic suture materials. Chordae tendineae and suture samples were tested in uniaxial tension using an INSTRON Model 1000 at strain rates of 5 and 10 mm/min. The stress (g/mm2) was plotted versus strain, and the elastic modulus determined as the slope of the curve. Chordae tendineae exhibited a nonlinear viscoelastic stress/strain behavior. The elastic modulus of both suture types tested was significantly higher than that of the chordae. However, the PTFE suture did exhibit some viscoelastic characteristics (hysteresis and creep) that begin to approach the chordal behavior. Chordal viscoelastic behavior results from the inherent composite structure (collagen, elastin, endothelium, water, and ground substance). As yet, no synthetic materials are able to imitate this behavior with the appropriate tensile strength and fatigue resistant characteristics. At present, PTFE appears to be the best synthetic alternative for chordal replacement, due to its limited viscoelastic capabilities. Nevertheless, the need to more nearly approximate the mechanical behavior of mitral valve chordae tendineae with synthetic material warrants further investigation.     

Mitral regurgitation due to ruptured chordae tendineae. Early and late results of valve repair

From 1958 through 1980, 131 patients had repair of ruptured chordae tendineae of the mitral valve; 62% were men. Ages ranged from 5 to 70 years (median 57). Chordae to the anterior mitral leaflet were ruptured in 44 patients (34%), to the posterior mitral leaflet in 85 (65%), and to both leaflets in two patients (1%). The mitral valve was repaired by leaflet plication without resection in 116 patients, plication after wedge resection of the unsupported leaflet in six, Ivalon sponge buttress of the posterior leaflet in three, resuspension of chordae in two, and annuloplasty alone in the remaining four. Mitral valve annuloplasty was performed in addition to leaflet repair in 115 patients (88%). Operative (less than 30 days) mortality was 6.1%. Survival rate of patients dismissed from the hospital was 92% at 5 years and 73% at 10 years. There were no differences in late survival or risk of reoperation for recurrent or residual mitral insufficiency between patients with ruptured chordae to the anterior leaflet and those with ruptured chordae to the posterior leaflet. Survival was significantly better for the group with repair than it was for a group that underwent mitral valve replacement for ruptured chordae during this same time interval (5 year survival rate, 92% versus 72%, p less than 0.003). The incidence of thromboembolism after repair was 1.8 episodes/100 patient-years compared with 8.0 episodes/100 patient-years after replacement. Our data indicate that valvuloplasty is the procedure of choice for most patients with mitral regurgitation owing to ruptured chordae tendineae, including selected patients with ruptured chordae to the anterior leaflet.     

Anterior mitral leaflet prolapse as a primary cause of pure rheumatic mitral insufficiency

BACKGROUND: This study was designed to revise the mechanisms and repair techniques of anterior mitral leaflet prolapse observed during the correction of pure rheumatic mitral regurgitation in children. METHODS: From March 1993 to May 1998, 36 children suffering from pure rheumatic mitral regurgitation due to anterior leaflet prolapse underwent mitral valve repair. The mean age was 12.5 years (range, 6 to 16 years). Anterior leaflet prolapse was due to chordal elongation in 25 patients (group A), chordal rupture in 6 patients (group B), and retraction of anterior secondary chordae tendineae, creating a V-shaped deformity in the middle of the anterior leaflet, thus moving the free edge of the anterior leaflet away from the coaptation plane, in 5 patients (group C). Chordal shortening, transposition, and resection of anterior secondary chordae tendineae were used to correct anterior leaflet prolapse according to the predominantly responsible mechanism. RESULTS: All patients were available for clinical follow-up, which ranged from 6 months to 5 years (mean follow-up, 3 years). Echocardiographic studies were obtained until the 3rd postoperative month, and all patients showed significant improvement in their left ventricular and atrial dimensions. There was one late death related to endocarditis. Two patients in group C who had mitral valve repair underwent mitral valve replacement on the 19th and 24th postoperative months, respectively, because of failure of mitral valve repair. CONCLUSIONS: Mitral valve repair for pure mitral regurgitation due to rheumatic anterior leaflet prolapse can be performed safely for all types of mechanisms. Although the techniques we used provide stable short-term results in each of these groups, midterm results are better in groups A and B, where tissue thickening is less important, recurrences of rheumatic carditis are lower, and the interval between the first rheumatic attack and the surgical procedure is shorter than in group C.     

Systolic anterior motion of the mitral valve despite the sliding leaflet technique for repair of the mitral valve

We report a systolic anterior motion of the anterior mitral leaflet despite employing the sliding leaflet technique for repair of mitral valve regurgitation. A 65-year-old man with chronic, symptomatic mitral regurgitation due to ruptured chordae tendineae underwent mitral valve repair by quadrangular resection of the posterior leaflet and sliding leaflet technique with ring annuloplasty. After weaning from cardiopulmonary bypass, left ventricular outflow obstruction developed and transesophageal echocardiography demonstrated systolic anterior motion of the mitral valve and severe mitral regurgitation. Non-operative treatment resolved the outflow tract obstruction, systolic anterior motion and mitral regurgitation. We conclude that post-repair systolic anterior motion can still occur after the sliding plasty procedure and that medical treatment can successfully resolve systolic anterior motion and outflow tract obstruction in most patients.     

Valve repair for mitral regurgitation due to ruptured chordae tendineae--repaired valve function and late results]

Among 21 consecutive patients with significant mitral regurgitation due to ruptured chordae tendineae operated by an author (K.M.) between March, 1980 and August, 1990, the 18 patients who underwent mitral valve repair were studied to assess the repaired valve function and late results of the repair. The chordal rupture was due to idiopathic degenerative disease in 14 patients, infective endocarditis in three and trauma in one. Patients' ages ranged from 35 to 70 years (mean age 52). Nine patients were in New York Heart Association class II and the remaining nine in class III. In three patients with ruptured chordae of the anterior mitral leaflet, reconstruction of the chordae with xenograft pericardium was performed in two patients and partial closure of a commissure in one. In 15 patients with ruptured chordae of the posterior leaflet, Kay's repair was performed in 13 patients and leaflet resection technique in two. In addition to the chordal and leaflet repairs, Kay's mitral annuloplasty was performed in all. There was no hospital death and all patients showed significant hemodynamic improvement (systolic pulmonary arterial pressure from 43 +/- 20 mmHg preoperatively to 24 +/- 4 mmHg postoperatively, and pulmonary arterial wedge pressure from 17 +/- 10 mmHg to 6 +/- 3 mmHg, p less than 0.001 respectively). The repaired valves showed mild pressure gradient of 3.1 +/- 1.2 mmHg which was significantly lower than the gradient of 6.6 +/- 3.5 mmHg of SJM prostheses. Residual murmur was documented in six patients, in three of whom, however, the murmur disappeared within one year following the operation.(ABSTRACT TRUNCATED AT 250 WORDS)     

实时三维超声在人工腱索二尖瓣成形术中的应用

目的 评价实时三维超声心动图在人工腱索植入行二尖瓣成形术中的应用价值.方法 31例二尖瓣脱垂病人,采用4-0 Goretex线为材料构建人工腱索行二尖瓣成形术,在术前、术中和术后分别行实时三维超声心动图检查.术前测量病人的正常腱索长度,通常测量二尖瓣前叶A1节段和后叶P1节段的腱索长度,以指导手术方案的制定.术中和术后采用实时三维超声检查以评价手术治疗效果.术中所有病人均同时植入人工二尖瓣成形环.结果 无手术死亡病例,体外循环(142.0±31.2)min、主动脉阻断(98.0±22.5)min.每例病人植入人工腱索1～3根,平均(2.0±1.5)根.术前三维超声测量的人工腱索的预期长度平均为(21.0±2.5)mm,术中实际植入的人工腱索的长度平均为(20.0±2.2)mm,二者比较差异无统计学意义.随访3～30个月,随访率98%.出现轻微反流15例,轻度反流1例,中度反流1例,无需再次手术治疗病例.未发现Goretex线人工腱索断裂,无后期死亡.结论 人工腱索植入二尖瓣成形术可获得良好的近、中期效果,实时三维超声可准确预测人工腱索的长度,对提高手术效果有重要帮助.     

Artificial chordae

Expanded polytetrafluoroethylene sutures have been used for replacement of chordae tendineae since 1985. They have been used for correction of prolapse of mitral and tricuspid valve leaflets as well as for resuspension of the papillary muscles during mitral valve replacement when the native chordae cannot be preserved to maintain continuity between the mitral annulus and papillary muscles. The sutures used were 5CV Gore-Tex for replacement of the chordae tendineae of the anterior leaflet and 6CV for the posterior leaflet and commissural areas of the mitral valve. Initially one suture was used to create two artificial chordae, but as experience increased, the technique was modified and multiple pairs of artificial chordae were created with a single suture by passing successively through the fibrous portions of the a papillary muscle and the free margin of the prolapsing segment of leaflet, and tying the tends together on the papillary muscle head. This technique creates artificial chordae that are interdependent and their lengths are self-adjusting when pressure is exerted on the leaflets. From 1985 to 1998, 288 patients had artificial chordae used during mitral valve repair for degenerative disease of the mitral valve. Prolapse of both leaflets was present in 51% of patients, isolated prolapse of the anterior leaflet in 28%, and posterior leaflet in 21%. The mean follow-up was 4.8 +/- 3.0 years and was complete. At 10 years, the freedom from mitral regurgitation >2+ was 88 +/- 6% and the freedom from reoperation was 92 +/- 2%. Failures of repair were unrelated to the artificial chordae. Gore-Tex sutures are an excellent material to replace chordae tendineae, appear to be free of adverse effects, and have become a valuable adjunct to the surgical armamentarium to treat mitral and tricuspid valve disease.     

Imbalanced chordal force distribution causes acute ischemic mitral regurgitation: mechanistic insights from chordae tendineae force measurements in pigs

BACKGROUND: Ischemic mitral regurgitation is caused by an imbalance of the entire mitral-ventricular complex. This interaction is mediated through the chordae tendineae force distribution, which may perturb several elements of the mitral valve apparatus. Our objective was to investigate the association between the mitral valvular 3-dimensional geometric perturbations and chordae tendineae force redistribution in a porcine model of acute ischemic mitral regurgitation. METHODS: In 9 pigs, acute ischemic mitral regurgitation was induced by repeated microembolization of the left circumflex coronary artery. Mitral leaflet coaptation geometry was determined by 2-dimensional echocardiography and reconstructed 3-dimensionally. Leading edge chordal forces were measured by dedicated miniature force transducers at control and during ischemic mitral regurgitation. RESULTS: During acute ischemic mitral regurgitation, there was a decreased tension of the primary chorda from the ischemic posterior left ventricular wall to the anterior leaflet (0.295 +/- 0.063 N vs 0.336 +/- 0.071 N [control]; P < .05). The tension of the chorda from the nonischemic anterior left ventricular wall to the anterior leaflet increased (0.375 +/- 0.066 N vs 0.333 +/- 0.071 N [control]; P < .05). In accordance, relative leaflet prolapse was observed at the ischemic commissural side, whereas there was an increase in the leaflet surface area at the nonischemic commissural side, indicating localized leaflet tethering. CONCLUSIONS: Acute ischemic mitral regurgitation due to posterior left ventricular wall ischemia was associated with focal chordal and leaflet tethering at the nonischemic commissural portion of the mitral valve and a paradoxical decrease of the chordal forces and relative prolapse at the ischemic site of the anterior mitral valve leaflet.     

Characteristics and treatment strategies of mitral regurgitation associated with undifferentiated papillary muscle

Purpose

In this report we review our experience of operations on mitral regurgitation associated with abnormal papillary muscles/chordae tendineae of the mitral valves and discussed the clinical characteristics, operative findings, and treatment strategies.

Methods

Undifferentiated papillary muscle was defined as a hypoplastic chordae tendineae with anomalous formation of papillary muscles attached to the mitral valves directly. Consecutive 87 patients undergoing surgery for mitral regurgitation at our institution were reviewed and 6 of them had undifferentiated papillary muscle.

Results

The underlying mechanism of regurgitation was prolapse at the center of the anterior leaflet in 3 cases and tethering, a wide area of myxomatous degeneration, and annular dilatation in one case, respectively. Five patients underwent mitral valve plasty and 1 patient received replacement. Anomalous formation of chordae tendineae was corrected by resection and suture with transplantation at the tip of the leaflet to which abnormal chordae were attached in 2 cases, while resection and suture with chordal shortening was performed in 1 case, and chordal reconstruction using artificial chordae was employed in 2 cases. There was no operative death, and postoperative echocardiography showed no residual regurgitation in any of the cases.

Conclusions

Mitral regurgitation associated with undifferentiated papillary muscle resulted from prolapse or tethering and impaired flexibility of leaflets. It was possible to successfully treat the patients by mitral valve plasty unless complex congenital cardiac malformation coexisted. Detailed examinations of attached papillary muscle by echocardiography and intraoperative inspection are necessary and surgical techniques should be selected appropriately in each case.

     

Mitral valve repair by replacement of chordae tendineae with polytetrafluoroethylene sutures

Expanded polytetrafluoroethylene sutures have been used for replacement of diseased chordae tendineae during reconstructive procedures on the mitral valve in 43 patients. There were 28 men and 15 women whose mean age was 55 years, range 21 to 76. Three fourths of the patients were in New York Heart Association class III or IV. Replacement of primary chordae tendineae of the anterior leaflet was performed with 4-0 or 5-0 polytetrafluoroethylene sutures. A double-armed suture was passed twice through the fibrous portion of the papillary muscle head and tied down. Each arm of the suture was brought up to the free margin of the leaflet and passed through the area where the native chorda was attached. After the lengths of the two arms were adjusted, the ends were tied together on the ventricular side of the leaflet. Thirty patients had degenerative disease of the mitral valve; the incompetence was due to prolapse of the anterior leaflet in 14 patients and prolapse of the anterior and posterior leaflets in 16. Eleven patients had rheumatic mitral valve disease: four had stenosis, three had regurgitation, and four had mixed lesions. Two patients had ischemic mitral regurgitation caused by rupture of a papillary muscle head. There were no operative deaths. Patients have been followed up from 5 to 61 months, mean 13. Doppler echocardiographic studies were performed at regular intervals after the operation and revealed normal mitral valve function in most patients There were two failures that necessitated mitral valve replacement: one because of acute mitral regurgitation and the other because of hemolysis. There have been two late deaths, neither one valve related. Replacement of chordae tendineae with polytetrafluoroethylene sutures is simple and allows for reconstruction of the mitral valve in many patients who would otherwise require mitral valve replacement. Because our patients have been followed up for a limited time, the long-term results of this procedure remain unknown.     

A case report of surgical correction for congenital mitral regurgitation with subvalvular apparatus abnormality

We report a successful complex mitral valve plasty using port access minimally invasive cardiac surgery for congenital mitral regurgitation that presented as an abnormality of the subvalvular apparatus. A 16-year-old male patient received a diagnosis of mitral regurgitation resulting from tethering of the anterior mitral leaflet and posterior mitral leaflet caused by an abnormality in papillary muscle insertion and a hypoplastic chordae tendineae. The posterior leaflet was closely tethered to the tips of the papillary muscle with essentially no chordae tendineae. The flexibility of the leaflet was restored by surgically removing the abnormal chordae, and reconstruction of chordae tendinae of the anterior leaflet was carried out using three loops and of the posterior leaflet using one loop with a loop technique method. As an additional procedure for persistent regurgitation, an edge-to-edge technique to the posterior commissure side was performed, after which the mitral regurgitation disappeared.     

Treatment of ruptured or elongated anterior mitral valve chordae by partial transposition of the posterior leaflet: experience with 29 patients

We report a series of 29 patients, 5 to 75 years of age (mean age, 31.8 +/- 21.4 [SD] years), with pure mitral regurgitation caused by ruptured or elongated chordae of the anterior mitral leaflet. These patients underwent mitral valve repair by segmental transposition of the posterior leaflet with its attached chordae sutured to the free edge of the flail anterior leaflet. There were 2 hospital deaths. Follow-up ranged from 1 to 35 months (mean follow-up, 14.9 +/- 8.5 months). One patient is lost to follow-up. Two patients are in New York Heart Association Functional Class II; all others are in Class I. In 17 patients there is no detectable murmur; in 5 patients a mild to moderate systolic murmur can be detected, while 4 have a marked systolic murmur. The adequacy of the repair could be confirmed by Doppler echocardiography, which has shown no evidence of prolapse in 22 patients. A mild regurgitation jet is present in 4 patients, and a marked jet, in 3. Postoperative cardiac catheterization performed in 5 patients has confirmed the Doppler echocardiographic findings. Although longer follow-up is necessary, this technique appears adequate for repairing a major prolapse of the anterior leaflet caused by multiple ruptured or elongated chordae, therefore obviating the need for a prosthetic valve substitute.     

Mitral-valve repair without annuloplasty rings: results after repair of anterior leaflet versus posterior-leaflet defects using polytetrafluoroethylene sutures for chordal replacement.

OBJECTIVE: Defects of the anterior mitral leaflet (AML), including ruptured chordae, are often regarded as difficult or even impossible to repair. Chordal replacement may also be an option in extensive disease of the posterior mitral leaflet (PML). It has not yet been clearly defined whether the repair of either mitral leaflet using chordal-replacement techniques is as safe as the standard repair of the mitral valve (MV) including quadrangular resection and ring reduction alone. METHODS: Between October 1995 and June 1999, 160 patients underwent MV repair for mitral regurgitation (MR) in our institution. Chordal replacement with polytetrafluoroethylene (PTFE) sutures for elongated or ruptured chordae was performed in 72 (45%) patients. These patients were divided into two groups according to the location of the MV lesions: 48 patients with prolapse of the anterior or both leaflets (AML group) received an average of 2.2+/-1. 1 PTFE sutures for repair; in 24 patients with isolated PML defects (PML group), we used an average of 1.5+/-0.8 PTFE sutures. No prosthetic annuloplasty rings were used. Dilatation of the posterior mitral ring was corrected by PTFE suture annuloplasty. The remaining 88 patients underwent a standard mitral repair without chordal replacement. There were no statistically significant (NS) differences between the two groups (AML/PML) regarding age (59/62 years, P=0.49), left ventricular (LV) ejection fraction (64/66%, P=0. 6) and preoperative NYHA class (2.9/2.9, P=0.36). Postoperatively, all patients were followed by serial transthoracic echocardiography at 1 week and after 3, 6, 12 and 24 months by the same investigator. RESULTS: In-hospital mortality was 4.2% (2/48) in the AML group and 0% (0/24) in the PML group (P=0.55). Three of the AML patients (6. 3%) and one PML patient (4.2%) underwent reoperation for recurrent MR (P=1.0). The 1- and 2-year freedom from MV reoperation was 95. 1+/-3.4 and 92.6+/-4.2% in the AML group versus 95.0+/-4.9 and 95. 0+/-4.9% (P=0.67). The 1- and 2-year freedom from residual or recurrent MR grade 2 or higher was 97.6+/-2.4 and 94.9+/-3.5% (AML) versus 95.8+/-4.0 and 95.8+/-4.0% (PML) (P=0.97). CONCLUSIONS: We were unable to find statistically significant differences concerning mortality, freedom from recurrent MR and MV reoperation between the AML and PML groups. Extensive prolapse or chordal pathology of the anterior and PML can be corrected by chordal replacement. Using these techniques, stable repair can be achieved in more than 90% of patients at mid-term follow-up. Long-term observations are necessary to confirm the durability of this type of MV repair.     

Partial tricuspid valve transfer for repair of mitral insufficiency due to ruptured chordae tendineae

BACKGROUND: A new technique is suggested for the reconstructive surgical treatment of mitral regurgitation. It involves partial transfer of the tricuspid valve of the patient to the mitral valve, in order to provide chordae to correct anterior leaflet prolapse of the mitral valve, secondary to rupture of the chordae tendineae. METHODS: From January 1991 to May 1997, 20 patients with mitral insufficiency due to rupture of the chordae were operated on. The prevailing cause was myxomatous degeneration (70%). Patients were in New York Heart Association functional class III and IV. RESULTS: There were no hospital deaths. Two patients were reoperated on. Eighteen patients (90%) are alive with their own valves (class I and II). Doppler echocardiogram mean values were: ejection fraction, 0.65; left atrial diameter, 4.2 cm; mitral area, 2.4 cm2; mitral transvalvular gradient, 3.3 mm Hg. No regurgitation or mild regurgitation was observed in 16 (94.1%) of the 17 cases evaluated. Mean tricuspid valvular area was 3.3 cm2. In all cases, no tricuspid regurgitation was present or it was mild. CONCLUSIONS: Partial transfer of the tricuspid valve to the mitral valve is an effective procedure for the surgical treatment of mitral valve insufficiency secondary to ruptured chordae tendineae of the anterior leaflet.     

Mitral valve repair with artificial chordae: a review of its history, technical details, long-term results, and pathology

Mitral valve repair is considered the procedure of choice for correcting mitral regurgitation in myxomatous disease, providing long-term results that are superior to those with valve replacement. The use of artificial chordae to replace elongated or ruptured chordae responsible for mitral valve prolapse and severe mitral regurgitation has been the subject of extensive experimental work to define feasibility, reproducibility, and effectiveness of this procedure. Artificial chordae made of autologous or xenograft pericardium have been replaced by chordae made of expanded polytetrafluoroethylene (PTFE), a material with the unique property of becoming covered by host fibrosa and endothelium. The use of artificial chordae made of PTFE has been validated clinically over the past 2 decades and has been an increasing component of the surgical armamentarium for mitral valve repair. This article reviews the history, details of the relevant surgical techniques, long-term results, and fate of artificial chordae in mitral reconstructive surgery.     

Transposition of posterior leaflet for treatment of ruptured main chordae of the anterior mitral leaflet

A 13-year-old girl with mitral regurgitation resulting from rupture of multiple chordae of the anterior leaflet had repair by transposition of a part of the posterior leaflet to the free edge of the anterior mitral cusp. Postoperative clinical hemodynamic, and angiographic studies showed perfect function of the mitral valve. This technique seems to be a good solution for mitral repair in the presence of ruptured anterior mitral chordae.     

Mitral valve repair for anterior leaflet prolapse: surgical techniques review and 16-year follow-up results

Abstract   Objective: Mitral valve repair is now the surgical treatment of choice for mitral regurgitation. However, the repair of anterior leaflet prolapse due to chordal rupture or elongation remains a technically challenging procedure. Here, we review our experience and present the long-term results of mitral valve repair for mitral regurgitation due to anterior leaflet prolapse. Methods: Between January 1988 and August 2006, 210 patients with mitral regurgitation underwent mitral valve reconstruction. We performed mitral valve repair in 49 patients with mitral regurgitation due to anterior leaflet prolapse. The preoperative degree of mitral regurgitation was moderate to severe in all patients. There were 36 patients (73.5%) with degenerative, eight (16.3%) with infective endocarditis, and five (10.2%) with rheumatic. Reconstructive techniques included chordal replacement in 13 patients, chordal shortening in 14, chordal transposition in five, chordal shortening and reinforcement with artificial chordae in four, leaflet folding plasty in six, and resection-suture in four. Results: Follow-up was complete with an average of 89 ± 59 months (range 1–201 months). In the early postoperative period, transthoracic echocardiography was performed in all patients. The grade of regurgitation was trivial (Grade I) in 17 patients (34.7%) and mild (Grade II) in seven patients (14.3%). Survival rate at 10 and 15 years was 95.2% and 88.9%, respectively. Freedom from reoperation at 10 and 15 years was 95.8% and 89.0%, respectively. Conclusions: The long-term results of mitral valve repair for anterior leaflet prolapse are satisfactory, with low mortality and morbidity. In particular, chordal replacement using temporary Alfieri stitch is a simple and effective procedure.