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1.
A bstract Since September 1991, 20 patients with mitral stenosis underwent mitral valve replacement and chordal replacement with expanded polytetrafluoroethylene (ePTFE) sutures. The continuity between the papillary muscles and the mitral annulus was maintained by four mattress sutures of ePTFE, which connected the stumps of the papillary muscle heads to the mitral annulus at the 2, 4, 8, and 10 o'clock positions. Low profile bileaflet prosthetic valves were inserted. There was no mortality either in-hospital or during follow-up. There was no valve related morbidity, such as valve structural failure, thromboembolism, anticoagulant related hemorrhage, prosthetic valve endocarditis, or posterior left ventricular rupture. The technique of replacing chordae tendineae is described in detail.  相似文献   

2.
OBJECTIVE: We sought to investigate whether annular or subvalvular interventions corrected chronic ischemic mitral regurgitation differently. METHODS: Sheep underwent placement of markers on the left ventricle, mitral annulus, papillary muscles (anterior and posterior), and both leaflet edges. A transannular suture (septal-lateral annular cinching) was anchored to the midseptal mitral annulus and externalized through the midlateral mitral annulus. Another suture (papillary muscle repositioning) from the posterior papillary muscle was passed through the mitral annulus near the posterior commissure and externalized. After 7 days, 3-dimensional marker data were obtained before inducing posterolateral myocardial infarction. After 7 weeks, animals in whom chronic ischemic mitral regurgitation developed (n = 10) were restudied before and after pulling septal-lateral annular cinching or papillary muscle repositioning sutures. End-systolic septal-lateral annular diameter and 3-dimensional displacement of the papillary muscles and leaflet edges were computed. RESULTS: Infarction increased mitral regurgitation (0.6 +/- 0.5 to 2.3 +/- 1.1); mitral annular septal-lateral dilation (4 +/- 1 mm); posterior papillary muscle displacement laterally (4 +/- 2 mm), posteriorly (9 +/- 3 mm), and toward the annulus (2 +/- 1 mm); posterior mitral leaflet apical tethering (3 +/- 1 mm); and interleaflet separation (+3 +/- 1 mm, P < .05 baseline vs chronic ischemic mitral regurgitation). Septal-lateral annular cinching reduced septal-lateral dimension (-9 +/- 3 mm), corrected lateral posterior papillary muscle displacement (4 +/- 1 mm) and septal-lateral interleaflet separation (-4 +/- 2 mm), and decreased mitral regurgitation (0.6 +/- 0.6, P < .05 septal-lateral annular cinching vs chronic ischemic mitral regurgitation) without affecting posterior leaflet restriction. Papillary muscle repositioning reduced septal-lateral diameter (-4 +/- 1 mm), moved the anterior papillary muscle closer to the annulus (2 +/- 1 mm), and relieved posterior leaflet apical restriction (2 +/- 1 mm, P < .05 papillary muscle repositioning vs chronic ischemic mitral regurgitation) but did not change lateral posterior papillary muscle displacement or decrease mitral regurgitation (1.9 +/- 1.2). CONCLUSIONS: Septal-lateral annular cinching moved the lateral annulus and the posterior papillary muscle closer to the septum and reduced mitral regurgitation unlike posterior papillary muscle repositioning, and thus the key mitral subvalvular repair component must correct posterior papillary muscle lateral displacement.  相似文献   

3.
BACKGROUND: Patients with chronic coronary artery disease have double the mortality rate if the condition is combined with functional mitral regurgitation. An understanding based on geometric alterations of the mitral apparatus in functional mitral regurgitation is desirable. METHODS: Twenty-nine subjects were enrolled in the study, including 9 healthy volunteers (control group), 12 patients with chronic coronary artery disease without functional mitral regurgitation (CAD group), and 8 patients with chronic coronary artery disease with functional mitral regurgitation (CAD+FMR group). Cine magnetic resonance imaging was performed to acquire multiple short-axis cine images from base to apex. Left ventricular end-systolic volume, left ventricular ejection fraction, mitral area, and vertices of the mitral tetrahedron, defined by medial and lateral papillary muscle roots and anterior and posterior mitral annulus, were determined from reconstructed images at end-systole. Anterior-posterior annular distance, interpapillary distance, and annular-papillary distance (the distance from the anterior or posterior mitral annulus to the medial or lateral papillary muscle roots) were calculated. RESULTS: Left ventricular end-systolic volume was inversely associated with left ventricular ejection fraction (R(2) = 0.778). Left ventricular end-systolic volume was highly associated with distances related to ventricular geometry (R(2) = 0.742 for interpapillary distance, 0.792 for the distance from the anterior mitral annulus to the medial papillary muscle root, and 0.769 for distance from the anterior mitral annulus to the lateral papillary muscle root) but was moderately associated with distances related to annular geometry (R(2) = 0.458 for anterior-posterior annular distance and 0.594 for mitral area, respectively). Moreover, interpapillary distance of greater than 32 mm and distance from the anterior mitral annulus to the medial papillary muscle root of greater than 64 mm readily distinguished the CAD+FMR group from the other groups. CONCLUSION: In patients with coronary artery disease, an increase in left ventricular end-systolic volume is associated with inadequate approximation of the mitral tetrahedron during systole, which consequently leads to functional mitral regurgitation. Our study suggests that interpapillary distance and distance from the anterior mitral annulus to the medial papillary muscle root are sensitive to the increase in left ventricular end-systolic volume and reliably indicate the presence of functional mitral regurgitation.  相似文献   

4.
OBJECTIVE: Although it is known that the papillary muscles ensure the continuity between the left ventricle (LV) and the mitral apparatus, their precise mechanism needs further study. We hypothesize that the papillary muscles function as shock absorbers to maintain a constant distance between their tips and the mitral annulus during the entire cardiac cycle. MATERIALS AND METHODS: Sonomicrometry crystals were implanted in five sheep in the mitral annulus at the trigones (T1 and T2), mid anterior annulus (AA) mid posterior annulus (PA), base of the posterior lateral scallops (P1 and P2), tips of papillary muscles (M1 and M2), and LV apex. LV and aortic pressures were simultaneously recorded and used to define the different phases of the cardiac cycle. RESULTS: No significant distance changes were found during the cardiac cycle between each papillary muscle tip and their corresponding mitral hemi-annulus: M1-T1, (3.5+/-2%); M1-P1 (5+/-2%); M1-PA (5+/-3%); M2-T2 (2.7+/-2%); M2-P2 (6.1+/-3%); and M2-AA (4.2+/-3%); (p>0.05, ANOVA). Significant changes were observed in distances between each papillary muscle tip and the contralateral hemi-mitral annulus: M1-T2 (1.7+/-3%); M1-P2 (23+/-6%); M1-AA (6+/-3%); M2-T1 (8+/-3%); M2-P1 (10.5+/-6%); and M2-PA (12.6+/-8%); (p<0.05 ANOVA). The distance changes between LV apex and each papillary muscle tip were significantly different: apex-M1 (12.9+/-1%) and apex-M2 (10.5+/-1%) and different from the averaged distance change between the LV apex and each annulus crystal (8.3+/-1%) with p<0.05. CONCLUSION: The papillary muscles seem to be independent mechanisms designed to work as shock absorbers to maintain the basic mitral valve geometry constant during the cardiac cycle.  相似文献   

5.
OBJECTIVE: Annuloplasty rings are used to treat ischemic mitral regurgitation (IMR), but their exact effects on 3-D geometry of the overall mitral valve complex during acute left ventricular (LV) ischemia remain unknown. METHODS: Radiopaque markers were sutured to the mitral leaflet edges, annulus, papillary muscle tips, and ventricle in three groups of sheep. One group served as control (n = 5), and the others underwent Duran (n = 6) or Physio (n = 5) ring annuloplasty. One week later, 3-D marker coordinates at end-systole were obtained before and during balloon occlusion of the circumflex artery. RESULTS: In all control animals, acute LV ischemia was associated with: (i) septal-lateral separation of the leaflet edges, which was predicted by lateral displacement of the lateral annulus during septal-lateral mitral annular dilatation; (ii) apical restriction of the posterior leaflet edge, which was predicted by displacement of the lateral annulus away from the non-ischemic anterior papillary muscle; (iii) displacement of the posterior papillary muscle, which was not predictive of either septal-lateral leaflet separation or leaflet restriction; and (iv) mitral regurgitation. In the Duran group during ischemia, the posterior leaflet edge shifted posteriorly due to posterior movement of the lateral annulus, but no IMR occurred. In the Physio group during ischemia, neither the posterior leaflet edge nor the lateral annulus changed positions, and there was no IMR. In both the Duran and Physio groups, displacement of the posterior papillary muscle did not lead to IMR. CONCLUSIONS: Either annuloplasty ring prevented the perturbations of mitral leaflet and annular--but not papillary muscle tip--3-D geometry during acute LV ischemia. By fixing the septal-lateral annular dimension and preventing lateral displacement of the lateral annulus, annuloplasty rings prevented systolic septal-lateral leaflet separation and posterior leaflet restriction, and no acute IMR occurred. The flexible ring allowed posterior displacement of the posterior leaflet edge and the lateral annulus, which was not observed with a semi-rigid ring.  相似文献   

6.
OBJECTIVE: Etiology-specific annular interventions and annuloplasty rings are now commercially available for the treatment of different types of mitral regurgitation; however, knowledge concerning the effects of local annular alterations on annular and left ventricular (LV) geometry is limited. METHODS: Seven adult sheep underwent implantation of eight radiopaque markers around the mitral annulus (MA) and eight markers on the LV (four each on two levels: basal and apical), and one on each papillary muscle tip. Trans-annular septal-lateral (SL) sutures were placed between the corresponding markers on the septal and lateral annulus at valve center (CENT) and near anterior (ACOM) and posterior (PCOM) commissures and externalized. Hemodynamic parameters and 4D marker coordinates were measured before and during SL annular cinching ('SLAC'; suture tightening 3-5 mm for 20s) at each suture location. Mitral annular SL diameter, annular area (MAA), and distance from the mid-septal annulus to the LV markers and papillary muscle tips were determined from marker coordinates every 17ms. RESULTS: End-systolic MAA decreased from 5.93+/-1.27 to 5.23+/-1.29(*)cm(2), 5.98+/-1.16 to 5.33+/-1.31(*)cm(2), and 6.30+/-1.65 to 5.61+/-1.37(*)cm(2) for SLAC(ACOM), SLAC(CENT), and SLAC(PCOM), respectively ((*)p<0.05 vs pre-cinching). Each SLAC intervention reduced the SL diameter at all three locations, while both SLAC(ACOM) and SLAC(CENT) affected ventricular geometry, and SLAC(PCOM) only slightly altered valvular-subvalvular distance. Only SLAC(CENT) altered papillary muscle position. CONCLUSIONS: Local annular SL reduction influences remote annular SL dimensions and affects LV geometry. The effect of local annular interventions on global annular geometry and LV remodeling should be considered in surgical or interventional approaches to mitral regurgitation and the design of new annular prostheses as well as supra-annular and sub-annular catheter interventions.  相似文献   

7.
We present a practical and accurate way to measure artificial chordae length in mitral valve repair. During preoperative transesophageal echocardiography, the distance between the head of the posterior papillary muscle and the mitral annulus plane at the coaptation of the leaflets is measured; this is the length of the new chorda. Every millimeter of braided 4-0 Gore-Tex (W.L. Gore & Assoc, Flagstaff, AZ) contains two tight reverse knots; therefore, the number of the knots determines the accurate length of the artificial chorda.  相似文献   

8.
OBJECTIVE: The mechanism of higher incidence of ischemic mitral regurgitation in patients with inferior compared with anterior myocardial infarction despite less global left ventricular remodeling and dysfunction is controversial. We hypothesized that inferior myocardial infarction causes left ventricular remodeling, which displaces posterior papillary muscle away from its normal position, leading to ischemic mitral regurgitation. METHODS: In 103 patients with prior myocardial infarction (61 anterior and 42 inferior) and 20 normal control subjects, we evaluated the grade of ischemic mitral regurgitation on the basis of the percentage of Doppler jet area, left ventricular end-diastolic and end-systolic volumes, midsystolic mitral annular area, and midsystolic leaflet-tethering distance between papillary muscle tips and the contralateral anterior mitral annulus, which were determined by means of quantitative echocardiography. RESULTS: Global left ventricular dilatation and dysfunction were significantly less pronounced in patients with inferior myocardial infarction (left ventricular end-systolic volume: 52 +/- 18 vs 60 +/- 24 mL, inferior vs anterior infarction, P<.05; left ventricular ejection fraction: 51% +/- 9% vs 42% +/- 7%, P <.0001). However, the percentage of mitral regurgitation jet area and the incidence of significant regurgitation (percentage of jet area of 10% or greater) was greater in inferior infarction (percentage of jet area: 10.1% +/- 7.5% vs 4.4% +/- 7.0%, P =.0002; incidence: 16/42 (38%) vs 6/61 (10%), P <.0001). The mitral annulus (area = 8.2 +/- 1.2 cm2 in control subjects) was similarly dilated in both inferior and anterior myocardial infarction (9.7 +/- 1.7 vs. 9.5 +/- 2.3 cm2, no significant difference), and the anterior papillary muscle-tethering distance (33.8 +/- 2.6 mm in control subjects) was also similarly and mildly increased in both groups (35.2 +/- 2.4 vs 35.2 +/- 2.8 mm, no significant difference). However, the posterior papillary muscle-tethering distance (33.3 +/- 2.3 mm in control subjects) was significantly greater in inferior compared with anterior myocardial infarction (38.3 +/- 4.1 vs 34.7 +/- 2.9 mm, P =.0001). Multiple stepwise regression analysis identified the increase in posterior papillary muscle-tethering distance divided by body surface area as an independent contributing factor to the percentage of mitral regurgitation jet area (r2 = 0.70, P <.0001). CONCLUSIONS: It is suggested that the higher incidence and greater severity of ischemic mitral regurgitation in patients with inferior compared with anterior myocardial infarction can be related to more severe geometric changes in the mitral valve apparatus with greater displacement of posterior papillary muscle caused by localized inferior basal left ventricular remodeling, which results in therapeutic implications for potential benefit of procedures, such as infarct plication and leaflet or chordal elongation, to reduce leaflet tethering.  相似文献   

9.
BACKGROUND: Chronic ischemic mitral regurgitation (CIMR) is poorly understood and repair operations are often unsatisfactory. This study elucidates the mechanism of CIMR in an ovine model. METHODS: Sonomicrometry array localization measured the three-dimensional geometry of the mitral annulus and subvalvular apparatus in five sheep before and 8 weeks after a posterior infarction of the left ventricle that produced progressive severe CIMR. RESULTS: End systolic annular area increased from 647 +/- 44 mm(2) to 1,094 +/- 173 mm(2) (p = 0.01). Annular dilatation occurred equally along the anterior (47.0 +/- 5.6 mm to 60.2 +/- 4.9 mm, p = 0.001) and posterior (53.8 +/- 3.1 mm to 68.5 +/- 8.4 mm, p = 0.005) portions of the annulus. The tip of the anterior papillary muscle moved away from both the anterior and posterior commissures by 5.2 +/- 3.2 mm (p = 0.021) and 7.3 +/- 2.2 mm (p = 0.002), respectively. The distance from the tip of the posterior papillary muscle to the anterior commissure increased by 11.0 +/- 5.7 mm (p = 0.032) while the distance from the tip of the posterior papillary muscle to the posterior commissure remained constant. CONCLUSIONS: Progressive dilatation of both the anterior and posterior mitral annuli, increased annular area, and asymmetric ventricular dilatation combine to cause CIMR by distortion of mitral valve geometry and tethering of leaflet coaptation. Therefore complete ring annuloplasty may be superior to partial annuloplasty in the treatment of CIMR.  相似文献   

10.
The surgical treatment of chronic ischemic mitral regurgitation remains a challenging issue. Several procedures have been developed to correct displacement of the papillary-ventricular complex and to reduce tethering-induced regurgitation. We report a geometric approach to relocate the laterally displaced posterior papillary muscle towards the mitral annulus. This procedure is believed to be technically easy and useful, especially in cases in which the displaced posterior papillary muscle contributes to tethering-induced regurgitation.  相似文献   

11.
Recently, ischemic mitral regurgitation (IMR) has been shown to be an individual risk factor for ischemic heart disease. The main mechanism of IMR is tethering of the leaflet secondary to left ventricular (LV) dilatation. In this situation, surgical treatment for IMR has been limited to ring annuloplasty with varying degrees of effectiveness. However, mid-term follow-up studies have shown that the results obtained with this approach are not satisfactory. Therefore, there has been a need to develop additional techniques to achieve more secure repair of IMR. The characteristics of the mitral leaflet configuration in IMR are apical displacement of the leaflets relative to the annulus, concavity of the leaflets, and a dilated annulus. Our basic strategy for a tethered mitral valve is rigid ring annuloplasty and inward correction of the outwardly displaced papillary muscle. For the latter correction, we employ the overlapping method or septal anterior ventricular exclusion (SAVE) procedure for LV volume reduction in cases of broad antero-septal infarction, or elevate the posterior papillary muscle by folding the LV wall at the root of the posterior papillary muscle via a small incision in the inferior wall in cases of infero-posterior infarction. An additional procedure is chordal cutting in combination with rigid ring annuloplasty and papillary muscle imbrication in combination with LV volume reduction. We have successfully combined these methods with the aid of detailed echocardiographic studies in individual patients. However, long-term follow-up will be necessary before this approach can be routinely adopted.  相似文献   

12.
In patients with ischemic left ventricular dysfunction and functional mitral regurgitation, surgical treatment of mitral insufficiency remains a challenging issue. Several procedures have been described to restore a near to natural alignment between the mitral annulus and the laterally displaced papillary muscles. We report a new approach to relocate the displaced papillary muscles toward the mitral annulus and to reduce tethering in 8 patients, providing satisfactory initial results. Echocardiography showed mild or no mitral regurgitation at the follow-up (mean, 11.4 +/- 3.6 months; range = 7 to 14 months). This procedure is believed to be technically easy and beneficial in terms of mitral repair.  相似文献   

13.
Few instruments are currently available to test mitral valve function in an ex vivo state due to the technical difficulties involved. To investigate the native ex vivo mitral valve or prosthetic mitral valve with chordae, we developed a mitral valve adapter with an annulus suturing portion and 2 papillary muscle suturing sites that can be changed in angle, direction, and length of chordae. We used this adapter to test an ex vivo mitral apparatus in beagle dogs and evaluated the morphology and function of the mitral apparatus by endoscopy. Our newly designed mitral valve adapter proved extremely useful for examining the ex vivo mitral valve anatomy and function and for testing stentless mitral prostheses with annular-papillary muscle continuity.  相似文献   

14.
Left ventricular papillary muscle geometry is distorted in dilated non-ischemic hearts, and following anterior infarction caused by a wrap around left anterior descending artery occlusion. Loss of the apex creates a spherical left ventricular (LV) chamber, and subsequent dilation causes secondary mitral insufficiency by stretching the annulus, altering tethering of the chords and widening the dimension between the bases of papillary muscles to impair leaflet coaptation. This report will describe an intraventricular way to narrow the widened inter papillary muscle distance toward normal.  相似文献   

15.
The case of a 52-year-old woman with subvalvular aortic stenosis and aortic regurgitation is presented. Mitral regurgitation was associated, due to insertion of two abnormal chordae tendineae at the apex of the anterior papillary muscle and at the free border of the subvalvular membranous annulus. This abnormality displaced the anterior papillary muscle, thus applying a traction at the mitral leaflet. The patient was operated on through a valve-sparing approach, in which the discrete subaortic stenosis was removed through aortotomy and the ectopic chordae were excised. Suture mitral annuloplasty completed the procedure. Aortic and mitral insufficiency almost disappeared at follow-up. From the examination of this case and from a review of pertinent literature it emerges that in event of similar complex congenital abnormalities without intrinsic valve disease, a conservative approach should be chosen so that valve replacement can be avoided.  相似文献   

16.
A 20-year-old female patient underwent urgent surgery for extensive mitral valve endocarditis. All marginal chordae and rough zone of A3 leaflet, posterior commissure leaflet, and P3 leaflet down to the annulus became defective after complete debridement of infected tissues. After annular plication, defective leaflets and chordae were reconstructed with a piece of triangular shaped autologous pericardium. Top of the pericardium was directly attached to the posterior papillary muscle, side edges to remnant leaflets, and the base to the annulus, thus substituting for chordae and leaflets at once. No mitral regurgitation was observed during 3 years of follow-up after the operation.  相似文献   

17.
Mitral valve replacement was performed in 21 patients using a surgical technique that preserves the entire papillary muscle and chordal apparatus. With this technique, the anterior mitral leaflet is split from the center of the free edge toward the annulus. Bilateral incisions are made from the proximal end of this split to the two mitral commissures, detaching the anterior leaflet from the annulus. These two halves of the leaflet, with all chordae intact (corresponding to the anterolateral and posteromedial papillary muscles), are judiciously trimmed to remove areas of leaflet untethered by chordae tendineae and (when necessary) fibrous thickening; then swung posteriorly and sutured to the posterior mitral annulus using mattress sutures with pledgets. This surgical technique is expected to favor the preservation of left ventricular function and avoid occurrence of irreversible left ventricular dilation/dysfunction, and has been used successfully for calcific and degenerative etiologies, using both tilting disc valves and porcine bioprostheses. It is especially useful in the implantation of tilting disc and bileaflet mechanical prostheses because anterior subvalvular chordae tissue may interfere with the disc excursion and relocated to the posterior leaflet annulus.  相似文献   

18.
We describe a technique for insertion of a mitral valve prosthesis in the presence of a heavily calcified annulus. The valve leaflets are used for securing the prosthesis, and both the anterior and posterior chordae tendineae and papillary muscle complexes are preserved.  相似文献   

19.
Artificial chordae   总被引:2,自引:0,他引:2  
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.  相似文献   

20.
In mitral valve surgery, preservation of continuity between the papillary muscles, chordae, and annulus is associated with preservation of left ventricular function and reduced risk of postoperative left ventricular rupture. However, at mitral valve replacement, extensive annulus and leaflet calcification can necessitate resection of the posterior mitral leaflet. We describe a technique in which the anterior mitral leaflet and its subvalvular apparatus are used to reinforce the posterior mitral annulus after extensive debridement of calcium along the same annulus.  相似文献   

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