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Background and Aims of the Study: Although many studies have found that preservation of the continuity between the mitral annulus and the papillary muscles during mitral valve replacement improves postoperative left ventricular performance in patients with mitral regurgitation, much less research has been done in this respect in patients with mitral stenosis. We reviewed our experience with mitral valve replacement combined with chordae tendineae replacement in 29 patients with mitral disease, 26 of whom had mitral stenosis., Methods: During mitral valve replacement, continuity between the papillary muscle and annulus was restored with expanded polytetrafluoroethylene (ePTFE) mattress sutures, which were threaded into the compact portion of each papillary muscle and placed at the 2, 4, 8 and 10 o'clock positions in the mitral annulus. Postoperatively, the patients were followed by echocardiographic assessment and exercise (stress) radionuclide angiography testing. The stress test results were compared with those in patients who had undergone traditional mitral valve replacement, and also those in normal people., Results: There were no hospital deaths, complications, or cardiac deaths or events during a median follow up of two-and-a-half years. Echocardiography showed no postoperative cardiac dilatation. The stress tests found no significant differences between the ejection fraction in mitral stenosis patients who underwent conventional mitral valve replacement and in those who had valve replacement combined with ePTFE chordae tendineae replacement., Conclusions: A direct advantage of chordae-preserving mitral valve replacement over conventional replacement with respect to postoperative global left ventricular performance in patients with mitral valve stenosis has not been demonstrated. However, postoperative regional left ventricular contraction in patients with mitral stenosis has been observed to be better among those who have undergone the chordae-preserving procedure. Additional investigations are needed to elucidate the effects of this procedure in mitral stenosis, but we believe that the technique improves left ventricular performance and may decrease the risk of left ventricular rupture.

The clinical significance of the chordae tendinae regarding postoperative left ventricular performance was evaluated in 148 patients with mitral regurgitation or mitral stenosis who underwent either mitral valve replacement using St. Jude Medical valve with complete chordal preservation, or with conventional mitral valve replacement, or valve repair. Mitral valve replacement preserving the autologous chordae tendinae (n = 28) or replacing them with Gore-Tex sutures (n = 16) was performed in 44 patients, 24 with mitral regurgitation and 20 with mitral stenosis. Their hemodynamic parameters were compared to those of patients who underwent conventional mitral valve replacement involving 25 with mitral regurgitation and 28 with mitral stenosis, or who underwent valve repair in 24 with mitral regurgitation, or commissurotomy in 27 patients with mitral stenosis. The LV performance was analyzed by cineangiography in the early (mean 1.2 months), and by multiple gated blood scintigraphy (MUGA), or echocardiography (UCG) in the late postoperative periods (mean 5.4 years) in the three groups of patients. In the mitral regurgitation group, the LV ejection fraction (EF) was unchanged in the chordal preserved group, but it was decreased in the conventional replacement and repair groups. The LV contractility index was better in the chordal preserved than in the conventional group. Both the LVEF by MUGA, and LV fractional shortening (FS) by UCG were significantly higher after chordal preservation or repair than after conventional valve replacement. The chordal preserved group exhibited superior LV performance than the conventional group, especially in those with mitral regurgitation and depressed preoperative left ventricular function (EF < 0.50). There were no significant difference between the three groups in patients with mitral stenosis. The results support the concept that maintenance of continuity between the mitral annulus and the papillary muscle has a beneficial effect on postoperative left ventricular performance, especially in patients with mitral regurgitation and depressed preoperative left ventricular function, but had no major effect in patients with mitral stenosis.

We successfully repaired an anticipated large laceration of the ascending aorta occurring during sternal re-entry in a 68-year old woman undergoing replacement of a prosthetic aortic valve. Cerebral protection was ensured by using continuous retrograde cerebral perfusion via femoro-femoral bypass with deep hypothermia. The cooling time was 20 minutes. The minimum nasopharyngeal temperature was 15 degrees C and the duration of the retrograde perfusion was 11 minutes at a rate of 600 ml per minute. The postoperative course was uneventful and no neurological deficits occurred.

The mitral valve was replaced with a collar-reinforced prosthetic valve in 6 patients with a disrupted mitral annulus, in 3 because of infective endocarditis, including 2 patients with prosthetic valve endocarditis, in 2 because of a severely calcified mitral annulus, and in 1 who had previously undergone mitral valve replacement twice. Four patients had undergone prior mitral operations; these consisted of mitral valve replacement in 3 patients and mitral valve repair in 1. In all patients, the prosthesis was secured by double-layered sutures, with the first row of buttressed sutures passing through the leaflet or sutured to the left ventricular muscle and through the sewing cuff of the prosthetic valve. The second row of running sutures was then placed through an extended annular equine pericardial cuff of the prosthetic valve and the supraannular left atrial wall. In 2 patients, all chordae tendineae were preserved to maintain annulopapillary muscle continuity. All patients survived and have remained well for a mean of 22.3 months. There has been no prosthetic valve dehiscence, except for minimal paraprosthetic leakage in 1 patient. These results demonstrate that mitral valve replacement in patients with a disrupted mitral annulus can be successfully accomplished with a collar-reinforced prosthetic valve.

Postoperative left ventricular performance was evaluated in patients with mitral stenosis who underwent mitral valve replacement with maintenance of the continuity of the mitral anulus and papillary muscles. Mitral valve replacement with preservation of autologous chordae tendineae (n = 7) or their replacement with expanded polytetrafluoroethylene sutures (n = 14) was performed in 21 patients with mitral stenosis. Hemodynamic parameters were compared with those of 28 patients who underwent conventional mitral valve replacement and 27 patients who underwent open mitral valve commissurotomy. No deaths occurred in the early or late follow-up period. All hemodynamic parameters were improved after the operation, and no significant differences were detected among the three groups with regard to postoperative cardiac index or mitral valve area. No significant differences were observed in left ventricular end-diastolic volume index, end-systolic volume index, or contractility index, but the postoperative left ventricular ejection fraction in the chordal preservation and open commissurotomy groups was greater than that in the group having conventional mitral valve replacement. Postoperative regional shortening was greatest at the diaphragmatic portion in the chordal preservation group and at the long axis in the open commissurotomy group. In the mid-term postoperative period, although no differences were noted among the three groups in echocardiographic data or global ejection fraction measured by multigated equilibrium radionuclide angiography, the regional shortening at the anterolateral portion of the left ventricle in the chordal preservation and commissurotomy groups was greater than that in the group having conventional mitral valve replacement. Postoperative radionuclide angiography during exercise failed to demonstrate any difference between the ejection fraction in the chordal preservation group and that in the group having conventional mitral valve replacement.

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.

The clinical importance of preserving the chordae tendineae during mitral valve replacement was assessed by comparing the postoperative left ventricular performances in 68 patients who underwent mitral valve replacement (MVR) with complete chordal preservation (n = 19), conventional MVR (n = 25) or mitral valve repair (n = 24) and had full hemodynamic assessment before and after surgery. The pre- and postoperative left ventricular performances were analyzed using cineangiography, multiple-gated cardiac blood pool scintigraphy (MUGA), and echocardiography. In the early postoperative period, cineangiography revealed that the end-systolic volume index (ESVI) and the end-diastolic pressure were significantly higher in the conventional MVR group. The left ventricular ejection fraction was unchanged in the chordal preservation group, but was decreased in the mitral repair and conventional MVR groups. The end-systolic circumferential left ventricular wall stress (ESS) was significantly decreased in the chordal preservation and mitral repair groups, but was unchanged, and thus higher, in the conventional MVR group. The postoperative left ventricular contractility index (ESS/ESVI) was better in the chordal preservation than in the conventional MVR group. In the late postoperative period, both the left ventricular ejection fraction as measured by MUGA and the left ventricular fractional shortening as measured by echocardiography were significantly higher in the mitral repair and chordal preservation groups than in the conventional MVR group. This study supports the concept that the maintenance of continuity between the mitral annulus and the papillary muscles has a beneficial effect on postoperative left ventricular performance.

The postoperative regional left ventricular motion of 22 patients with a diagnosis of mitral regurgitation, and who underwent mitral valve replacement with preservation of chordae tendineae, were retrospectively analyzed by cineangiography in the early postoperative period and by multiple-gated cardiac blood pool scintigraphy in the mid-to-late postoperative period. The operation consisted of the division of the anterior leaflet into anterior and posterior segments, the shifting and reattachment of the divided segments to the mitral ring of the respective commissural areas, and the use of a low-profile bileaflet prosthetic valve. Control groups consisted of 28 patients with mitral regurgitation who underwent mitral valve replacement with a conventional technique and 16 patients who underwent mitral valve repair. Compared with the conventional mitral valve replacement group, the radial shortening of the left ventricle of the chordae-preserved mitral valve replacement group was greater at the apical septal, inferoapical, anterobasal, and anterolateral portions, whereas the radial shortening of the repair group was greater than that of the chordae-preserved group only at the inferolateral portion. The ejection fraction of the whole left ventricle was statistically greater in the chordae-preserved group, and also regional ejection fraction of the chordae-preserved mitral valve replacement group was greater at the apical septal, inferoapical, inferolateral, anterobasal, and anterolateral portions than that of the conventional mitral valve replacement group at these portions. On the other hand, the postoperative regional and global motion was identical to that of the mitral valve repair group except at the inferolateral portion. The result of this study supports a concept that maintenance of continuity between the mitral anulus and the papillary muscle has a beneficial effect on postoperative left ventricular performance.

A 49-year-old man who had undergone repair of tetralogy of Fallot underwent replacement of a thrombosed St. Jude Medical prosthesis in pulmonary position after intravenous thrombolytic therapy. Dysfunction of the prosthetic valve was detected clinically by change of heart sound and the appearance of a new diastolic murmur. Cinefluoroscopy confirmed fixation of both leaflets. Although thrombolytic therapy using urokinase was successful twice, the prosthesis was replaced with a Carpentier-Edwards bioprosthesis due to recurrent prosthetic dysfunction.

Between 1987 to 1990, six patients underwent replacement of the ascending aorta and aortic valve with a composite graft which was not wrapped with aneurysmal aortic wall; annuloaortic ectasia in 4, aortitis with acute onset of aortic regurgitation in 1, and acute aortic dissection with aortic regurgitation in 1. In 2 patients, "open aortic anastomosis" under deep hypothermic systemic circulatory arrest and retrograde cerebral perfusion was utilized for distal anastomosis of the graft to the resected aortic arch. Three patients required no transfusion. One patient with annuloaortic ectasia and severely dilated left ventricle died from ventricular fibrillation in ICU. One patient with aortitis died from stroke due to occlusion of bilateral carotid arteries 3 years postoperatively. The other 4 patients are alive and favorable. It is our belief that this technique still maintains simplicity and facilitates the secured anastomosis and minimized bleeding.

Nine patients with intractable hemolysis caused by perivalvular leakage following mitral valve replacement with a St. Jude Medical prosthesis are presented. All patients had dark-colored hemoglobinuria, which appeared from 1 day to 44 days after the operation, with moderate or severe hepatorenal insufficiency. One patient died of multiorgan failure. The other 8 patients underwent reoperation, and all survived. Reoperation revealed that all leakages were tiny and had no adverse effect on hemodynamics. In all the patients having reoperation, hemoglobinuria disappeared immediately after the procedure. Surface-scanning electron microscopy of the sewing cuff of the St. Jude Medical prosthesis revealed the rough surface structure of the sewing ring. Because of this irregular, shaggy surface structure, greater shearing forces against erythrocytes can be generated when there is perivalvular leakage.

A total of 20 patients underwent mitral valve replacement (MVR) with preservation of the papillary muscles (PM) and chordae tendineae (CT) with the object of maintaining left ventricular contractility and decreasing the risk of left ventricular rupture after surgery. The patients comprised of 8 males and 12 females whose ages ranged from 33 to 67 years. In 8 patients, the posterior leaflet was left in place and in 12, the CT to the anterior leaflet were also preserved by excision of the central portion and reattachment of the rest of the leaflet to the appropriate commissural regions. St. Jude Medical valves were exclusively employed as a substitute. Reasons for MVR were isolated MR in 12 cases, MRs in 5 and MSr in 3. There were one operative, one hospital and one late death respectively. Postoperative C.I. increased from 2.65 +/- 0.48 to 3.8 +/- 0.75 ml/min./M2 and LVEF increased from 55.1 +/- 11.4 to 63.4 +/- 13.4%. The area method showed marked improvement of segmental wall motion in anterolateral regions. Chordal shortening also disclosed improvement in long axis. Preservation of papillary muscles and chordae tendineae during MVR has been found to have a beneficial effect on postoperative left ventricular contractility.

Five patients underwent reoperations because residual or recurrent aortic regurgitation occurred after aortic valvuloplasty for aortic regurgitation associated with ventricular septal defect. The mean age at reoperation was 22 years old, and the mean time interval between initial and second operation was 6 years, 10 months. The pathological findings of the aortic valves showed tears and perforation of repaired leaflets in four patients and a giant pseudoaneurysm of the Valsalva sinus in one. Aortic valvuloplasties were performed again in three patients, and aortic valves were replaced with prosthetic valves in two. Slight to moderate regurgitant murmurs are still audible in patients who underwent these valvuloplasties. Ventricular septal defects should be closed before aortic regurgitation develops. If it has developed, however, valvuloplasty should be considered as a first choice in young patients. For adult patients, aortic valve replacement is recommended.

An operative technique for mitral valve replacement (MVR) with preservation of the chordae tendineae to the anterior leaflet as well as the posterior leaflet is reported. This technique consists of the division of the anterior leaflet into anterior and posterior segments, the shifting and reattachment of the divided segments to the mitral ring of the respective commissural areas, and the use of a low-profile bileaflet prosthetic valve. A comparison of left ventricular function data between patients having operation with this technique and those having operation with the conventional method of MVR revealed significantly better improvement in cardiac index (p less than 0.06), left ventricular end-systolic volume index (p less than 0.05), and left ventricular ejection fraction (p less than 0.10) in the former group. Left ventricular wall motion improved in the anterolateral (p less than 0.01) and apical areas (p less than 0.02) in patients operated on with our technique. Maintenance of continuity between the mitral annulus and papillary muscles is expected to have a beneficial effect on postoperative left ventricular performance in spite of increased afterload.