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Midterm results after seamless patch mitral reconstruction

Open AccessPublished:October 12, 2022DOI:https://doi.org/10.1016/j.xjtc.2022.10.006

      Abstract

      Objectives

      Some pathologies, including infective endocarditis or sclerotic changes of the mitral leaflet, make the conventional mitral valve repair challenging. Our previously described technique for reconstruction with a seamless pericardial patch makes the repair feasible in some of such difficult pathologies. However, the extent of mitral leaflet segments that could be safely repaired using this technique remains unknown. We investigated the association between the midterm outcome and the extent of mitral leaflet segments replaced by a pericardial patch.

      Methods

      From January 2009 to January 2022, patients who underwent mitral valve repair with the seamless 1-patch reconstruction technique were included. The glutaraldehyde-treated pericardium was trimmed and anchored at the papillary muscle. The edge was sewn to the leaflet and the annulus.

      Results

      A total of 49 patients (aged 60 ± 15 years) underwent mitral valve repair with this technique. The totally endoscopic approach was used in 27 patients (55%). No patient's repair was converted to valve replacement. No operative mortality or disabling stroke was observed during the early postoperative period. In the midterm follow-up, redo surgery was required in 9 patients (18%). Freedom from mitral valve reintervention rates at 1, 5, and 10 years were 84%, 82%, and 82% for all patients, respectively. Freedom from reoperation at 5 years was 100%, 92%, and 46% for commissural lesion, 1- to 2-segment involvement, and 3-segment involvement, respectively. There was a significant difference among the 3 groups with regard to mitral valve reoperation rate (P = .002).

      Conclusions

      Mitral valve seamless patch reconstruction provides excellent midterm results if applied to commissural lesions or lesions involving up to 2 segments.

      Key Words

      Abbreviations and Acronyms:

      MR (mitral regurgitation), MS (mitral stenosis), SRT (seamless patch reconstruction technique)
      Figure thumbnail fx1
      Mitral valve reconstruction with seamless patch technique.
      Mitral valve reconstruction with the seamless patch technique provides an excellent long-term result when applied to the pathologies involving the commissure or up to 2 segments.
      Durable repair of mitral valves with active endocarditis, small leaflet, or restrictive leaflet remains challenging. This approach is easily accessible technically and augments the surgeon's armamentarium, especially in young patients to avoid valve replacement.
      See Commentary on page XXX.
      Mitral valve repair is the standard of care for degenerative mitral regurgitation (MR) meeting operative indications.
      • Vahanian A.
      • Beyersdorf F.
      • Praz F.
      • Milojevic M.
      • Baldus S.
      • Bauersachs J.
      • et al.
      2021 ESC/EACTS guidelines for the management of valvular heart disease.
      ,
      • Nishimura R.A.
      • O’Gara P.T.
      • Bavaria J.E.
      • Brindis R.G.
      • Carroll J.D.
      • Kavinsky C.J.
      • et al.
      2019 AATS/ACC/ASE/SCAI/STS expert consensus systems of care document: a proposal to optimize care for patients with valvular heart disease: a joint report of the American Association for Thoracic Surgery, American College of Cardiology, American Society of Echocardiography, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons.
      Numerous techniques for mitral repair have been reported with good long-term outcomes.
      • Pfannmueller B.
      • Misfeld M.
      • Verevkin A.
      • Garbade J.
      • Holzhey D.M.
      • Davierwala P.
      • et al.
      Loop neochord versus leaflet resection techniques for minimally invasive mitral valve repair: long-term results.
      • David T.E.
      • Armstrong S.
      • McCrindle B.W.
      • Manlhiot C.
      Late outcomes of mitral valve repair for mitral regurgitation due to degenerative disease.
      • David T.E.
      • David C.M.
      • Lafreniere-Roula M.
      • Manlhiot C.
      Long-term outcomes of chordal replacement with expanded polytetrafluoroethylene sutures to repair mitral leaflet prolapse.
      However, durable repair of mitral valves with active endocarditis, small leaflet, or restrictive leaflet remains challenging. The difficulties are often related to the lack of sufficient leaflet tissue to provide adequate coaptation. To repair such pathologies, we reported our technique of “seamless” patch reconstruction using a glutaraldehyde-treated autologous pericardium.
      • Ito T.
      • Maekawa A.
      • Aoki M.
      • Hoshino S.
      • Hayashi Y.
      • Sawaki S.
      • et al.
      Seamless reconstruction of mitral leaflet and chordae with one piece of pericardium.
      ,
      • Ito T.
      • Maekawa A.
      • Sawaki S.
      • Fujii G.
      • Hoshino S.
      • Hayashi Y.
      Reconstruction of mitral valve chordae and leaflets with one piece of autologous pericardium in extensively destructed mitral valve due to active infective endocarditis.
      This technique uses a single piece of pericardium patch to cover the defective or diseased mitral leaflet with a good early outcome. As we have broadened the application of our technique to more extensive valve pathologies, we aimed to characterize the association between the long-term outcome and the extent of segments repaired.

      Materials and Methods

      Patient Selection

      This report was approved by the Institutional Review Board of the Japanese Red Cross Nagoya First Hospital (2021-429) April 1, 2021. The individual informed consent was waived. We retrospectively reviewed our database and included all the patients who underwent the seamless patch reconstruction technique (SRT). All of the patients who were planned preoperatively to undergo SRT successfully underwent SRT and were included in this series. Patients were considered as a candidate for SRT when the defect or sclerotic mitral leaflet was limited to 1 leaflet (regardless of the number of involved segments). We excluded patients who received leaflet repair by means other than autologous pericardium. We did not attempt SRT when the lesions were in both anterior and posterior leaflets. We investigated our perioperative and long-term outcomes stratified by the extent of leaflet replaced with SRT. Patients were divided into 3 groups: commissure leaflets replaced, 1 to 2 segments replaced, and 3 segments replaced. We analyzed the long-term outcomes in terms of the valve function.

      Surgical Technique

      A median sternotomy or an endoscopic approach was chosen on the basis of the patient's anatomy. All patients underwent cardiopulmonary bypass. Totally endoscopic procedures were performed through a right minithoracotomy without rib spreading.
      • Ito T.
      • Maekawa A.
      • Hoshino S.
      • Hayashi Y.
      • Sawaki S.
      • Yanagisawa J.
      • et al.
      Three-port (one incision plus two-port) endoscopic mitral valve surgery without robotic assistance.
      The autologous pericardium was harvested at the time of pericardiotomy. The harvested pericardium was soaked in 0.6% glutaraldehyde solution for 10 minutes and rinsed twice with normal saline for 10 minutes.
      The left atrium was opened at the Waterson groove. The mitral valve was repaired using the harvested pericardium. The edge of the prepared pericardium is attached to the base of the papillary muscle with a pledgetted 4-0 Gore-Tex (WL Gore & Associates Inc) suture. We refer the length or width of the leaflet to the adjacent leaflets and try not to shorten the leaflet or the length to the annulus. The pericardium was sewn to the native leaflet with a single interrupted 5-0 polypropylene suture (Figure 1, A-D, and Video 1) according to the valve anatomy. The annuloplasty was made if there is an annular dilatation. The details of the technique are also described in our previous reports.
      • Ito T.
      • Maekawa A.
      • Aoki M.
      • Hoshino S.
      • Hayashi Y.
      • Sawaki S.
      • et al.
      Seamless reconstruction of mitral leaflet and chordae with one piece of pericardium.
      ,
      • Ito T.
      • Maekawa A.
      • Sawaki S.
      • Fujii G.
      • Hoshino S.
      • Hayashi Y.
      Reconstruction of mitral valve chordae and leaflets with one piece of autologous pericardium in extensively destructed mitral valve due to active infective endocarditis.
      Figure thumbnail gr1
      Figure 1A-D, Schema of SRT applied to 1- or 2-segment involvement.
      After confirming the valve competency with saline injection to the left ventricle, the left atrium was closed with single-layer polypropylene sutures. The cardiopulmonary bypass was weaned after the resumption of the heart rhythm.

      Patient Follow-up

      Transthoracic echocardiography was performed preoperatively and before the hospital discharge. All the studies were reviewed by a cardiologist specialized in cardiac imaging (Y.M.). The degree of MR was according to the American Society of Echocardiography guideline. Each measured parameter was recorded at preoperative and at the time of long-term follow-up. The patients are followed at our clinic with an annual echocardiography. All patients received warfarin and aspirin for the first 3 months after the procedure, and aspirin was continued thereafter.

      Statistical Analysis

      Data were summarized as means ± standard deviation for continuous variables and number (%) for categorical variables. Echocardiographic characteristics of the mitral valve were compared preoperatively and postoperatively in echocardiographic measurements using the 2-tailed paired t test for ejection fraction, MR degree, and mean gradient across the mitral valve. Overall survival, freedom from redo surgery, and freedom from significant MR (more than mild) were displayed in Kaplan–Meier plots, and statistical significances were tested using the log-rank test. We also performed competing-risk analysis for freedom from significant MR and freedom from redo surgery to account for the competing mortality risk. The analysis was performed using SPSS 21 (IBM Corp) and cmprsk package for R Studio 4.2.1 (R Foundation).

      Results

      Preoperative Variables

      From January 2009 to January 2022, 49 patients underwent SRT in our institution using the described technique. During the same time period, 831 mitral valve procedures (surgical repair or replacement) were performed in our institutions. Patients’ mean age was 60 ± 15 years at the index surgery. All patients had moderate or severe MR, and 1 patient (2.0%) had moderate mitral stenosis (MS). Preoperative variables are summarized in Table 1.
      Table 1Preoperative characteristics
      Age (y ± SD)60 ± 15
      Male, n (%)23 (47)
      BMI (mean ± SD)21 ± 3.7
      Hypertension, n (%)16 (33)
      Diabetes, n (%)15 (31)
      Dyslipidemia, n (%)10 (20)
      History of CVD, n (%)5 (10)
      Smoking, n (%)16 (33)
      Chronic kidney disease, n (%)8 (16)
      Hemodialysis, n (%)3 (6)
      History of atrial fibrillation, n (%)22 (45)
      Ejection fraction (mean ± SD)59 ± 14
      Low EF, n (%)2 (4.1)
      NYHA (mean ± SD)2.7 ± 0.6
      Previous cardiac surgery, n (%)3 (6)
      Endocarditis, n (%)14 (29)
      Active endocarditis, n (%)8 (16)
      Posterior leaflet lesion, n (%)28 (57)
      Anterior leaflet lesion, n (%)9 (18)
      Commissure lesion, n (%)12 (24)
      Degenerative MR, n (%)26 (53)
      Functional MR, n (%)23 (47)
      Atrial functional MR, n (%)6 (12)
      Ventricular functional MR, n (%)9 (18)
      Carpentier classification
       Type I, n (%)0
       Type II, n (%)26 (53)
       Type IIIa, n (%)8 (16)
       Type IIIb, n (%)15 (31)
      SD, Standard deviation; BMI, body mass index; CVD, cerebrovascular disease; EF, ejection fraction; MR, mitral regurgitation; NYHA, New York Heart Association.

      Mitral Valve Pathologies and Type of Patch

      Details of the mitral valve pathologies and the Carpentier classification are shown in Table 1. The most common pathology was type II disease (26 patients, 53%). Posterior leaflet involvement was the majority in the group (28 patients, 57%). A total of 38 patients (78%) had a triangle- or pentagon-shaped patch, and 11 patients (22%) received a double pentagon attached to both anterolateral and posteromedial papillary muscle. A total of 12 patients (24%) received the patch around the commissure. A total of 26 patients (53%) had 1 or 2 segments replaced with a triangle- or pentagon-shaped patch (Figure 1). A total of 11 patients (22%) had 3 segments covered with the double pentagon–shaped patch. Four patients (8.2%) were treated with a loop technique for the coexisting type II lesion in addition to SRT. All of the patients received glutaraldehyde-treated autologous pericardium described above in terms of the patch used.

      Perioperative Variables

      Intraoperative and early postoperative characteristics are shown in Table 2. Seven patients (14%) underwent concomitant aortic valve replacement with a standard stented bioprosthesis. One patient (2.0%) had a concomitant root replacement, and 2 patients (4.1%) had coronary artery bypass grafting simultaneously. Tricuspid repair, maze procedure, and left atrial appendage closure were performed in 18 patients (37%), 13 patients (27%), and 24 patients (49%), respectively. Annuloplasty was performed in 41 patients (84%), including 3 patients with an annuloplasty ring from the previous surgery.
      Table 2Perioperative variables
      Totally endoscopic surgery, n (%)27 (55)
      Mitral annuloplasty, n (%)41 (84)
      Concomitant aortic valve replacement, n (%)6 (12)
      Concomitant root replacement, n (%)1 (2.0)
      CABG, n (%)2 (4.1)
      Left ventricular restoration, n (%)2 (4.1)
      Tricuspid valve repair, n (%)18 (37)
      Maze procedure, n (%)13 (27)
      Left atrial appendage closure, n (%)24 (49)
      Cardiopulmonary bypass time, min (mean ± SD)198 ± 61
      Aortic crossclamp time, min (mean ± SD)143 ± 46
      30-d mortality, n (%)0
      Disabling stroke, n (%)0
      Reexploration for bleeding, n (%)2 (4.1)
      Prolonged ventilation >72 h, n (%)1 (2.0)
      ICU stay, d, median (IQR)2 (1-3)
      Hospital stay, d, median (IQR)11 (9-16)
      CABG, Coronary artery bypass grafting; ICU, intensive care unit; IQR, interquartile range.
      Mean aortic crossclamp time and cardiopulmonary bypass time were 143 ± 46 minutes and 198 ± 61 minutes, respectively. All patients underwent mitral valve repair without the need for replacement. There was no 30-day mortality. Ischemic stroke occurred in 1 patient (2.0%). There was no conversion to sternotomy in patients planned for totally endoscopic approach (27 patients, 55%).

      Midterm Result

      The mean duration of the follow-up from the index surgery was 69 ± 41 months (range, 1-159). Follow-up was completed in 100% of the patients. Postoperative transthoracic echocardiographic results at latest follow-up are shown in Table 3. The mean duration of the transthoracic echocardiography was 55 ± 40 months (range, 1-159, 96% completeness in the midterm follow-up).
      Table 3Last follow-up transthoracic echocardiographic findings
      VariablesPredischargeFollow-upP value
      Ejection fraction, % (mean ± SD)52 ± 1557 ± 15.03
      Mean pressure gradient, mm Hg (mean ± SD)3.8 ± 2.73.9 ± 3.1.87
      Mean pressure gradient >5mm Hg, n (%)5 (10)7 (14).76
      SD, Standard deviation.
      In the midterm follow-up, redo surgery was required in 9 patients (18%). Of those, a double pentagon patch for 3-segment lesion was used in 6 patients (67%) at the initial operation. The reasons for redo surgery were a tear in the patch in 2 patients (4.1%), sclerotic change in remnant leaflet tissue in 2 patients (4.1%), and hemolysis in 2 patients (4.1%). One patient had redo for MS 8 years after the repair. The details of the redo surgery are shown in Table E1. No recurrence of MR was found in the cases of commissural involvement. Three patients required reoperations (12%) among those who had 1 or 2 segments replaced, and 6 patients required reoperations (55%) among those who had 3 segments replaced.
      The 1-, 5-, and 10-year survivals were 96%, 80%, and 80% for all patients, respectively, and freedom from cardiac mortality was 96%, 90%, and 90% for all patients, respectively. Long-term survival was not significantly different in the 3 subgroups of commissural lesion, 1- to 2-segment involvement, and 3-segment involvement (P = .35, Figure 2).
      Figure thumbnail gr2
      Figure 2Actuarial overall survival and cardiac death after seamless patch mitral reconstruction in the commissural, up to 2-segment, and 3-segment involvement groups.
      Freedom from mitral valve reintervention rates at 1, 5, and 10 years were 84%, 82%, and 82% for all patients, respectively. There was a significant difference among the 3 groups with regard to mitral valve reoperation in competing risk of death and reoperation by the extent of leaflet involvement (P = .005, Figure E1). Freedom from reoperation rates at 5 years were 100%, 92%, and 46% for commissural lesion, 1- to 2-segment involvement, and 3-segment involvement, respectively. In terms of freedom from more than mild mitral valve regurgitation, there was a significant difference among the 3 groups in competing risk of death and reoperation by the extent of leaflet involvement (P = .019, Figure E2). Freedom from more than mild MR rates at 5 years were 100%, 84%, and 58% for commissural lesion, 1- to 2-segment involvement, and 3-segment involvement, respectively.

      Discussion

      We previously described our technique and early outcome of this seamless patch reconstruction.
      • Ito T.
      • Maekawa A.
      • Aoki M.
      • Hoshino S.
      • Hayashi Y.
      • Sawaki S.
      • et al.
      Seamless reconstruction of mitral leaflet and chordae with one piece of pericardium.
      ,
      • Ito T.
      • Maekawa A.
      • Sawaki S.
      • Fujii G.
      • Hoshino S.
      • Hayashi Y.
      Reconstruction of mitral valve chordae and leaflets with one piece of autologous pericardium in extensively destructed mitral valve due to active infective endocarditis.
      Our previous study demonstrated its effectiveness and reproducibility in the short-term. The results of our current study are consistent with previous reports of the fresh autologous pericardium.
      • Ng C.K.
      • Nesser J.
      • Punzengruber C.
      • Pachinger O.
      • Auer J.
      • Franke H.
      • et al.
      Valvuloplasty with glutaraldehyde-treated autologous pericardium in patients with complex mitral valve pathology.
      • Shomura Y.
      • Okada Y.
      • Nasu M.
      • Koyama T.
      • Yuzaki M.
      • Murashita T.
      • et al.
      Late results of mitral valve repair with glutaraldehyde-treated autologous pericardium.
      • Quinn R.W.
      • Wang L.
      • Foster N.
      • Pasrija C.
      • Ghoreishi M.
      • Dawood M.
      • et al.
      Long-term performance of fresh autologous pericardium for mitral valve leaflet repair.
      The rate of freedom from reoperation in patients who underwent SRT was 82% at 5 years, comparable to those previous studies ranging from 82% to 89% at 5 years. Our study represents one of the largest series of mitral repair using autologous pericardium.
      Our data demonstrated that the anatomic location of the SRT application was associated with midterm durability of the repair. The SRT patch implanted at the commissure had no recurrence in the midterm. The SRT patch covering 1 to 2 segments also had excellent midterm outcomes. On the other hand, if applied to more than 2 segments, SRT had a higher incidence of recurrence compared with the less-extensive repair. We applied this technique for patients who otherwise would have received a valve replacement, such as infective endocarditis or type III lesion. We consider the midterm result acceptable when applied to the limited lesion to salvage the native valve. A limitation of our study is that the included population is heterogenous and the variation in outcomes may partly be due to the variation in pathology. On the basis of the repair durability data presented, the extent of segments involved may be a unifying variable that could guide the patient selection for appropriate SRT candidates, regardless of the valve pathologies or etiologies. The study investigates a small number of patients retrospectively, and a larger number of patients are necessary to corroborate our findings. In addition, a learning curve effect may play a relevant role in this setting.

      Study Limitations

      A possible drawback of this technique is the potential inflow obstruction by the pericardial patch, as described in previous reports.
      • Ito T.
      • Maekawa A.
      • Aoki M.
      • Hoshino S.
      • Hayashi Y.
      • Sawaki S.
      • et al.
      Seamless reconstruction of mitral leaflet and chordae with one piece of pericardium.
      In our series, 3 patients had more than moderate MS in the midterm, including a patient with rheumatic mitral morphologies. In most of the patients (94%), the MS was negligible with a mean pressure gradient of 3.9 mm Hg. The use of fresh autologous pericardium in mitral repair has been reported to rarely incur calcification in the long-term.
      • Shomura Y.
      • Okada Y.
      • Nasu M.
      • Koyama T.
      • Yuzaki M.
      • Murashita T.
      • et al.
      Late results of mitral valve repair with glutaraldehyde-treated autologous pericardium.
      ,
      • Quinn R.W.
      • Wang L.
      • Foster N.
      • Pasrija C.
      • Ghoreishi M.
      • Dawood M.
      • et al.
      Long-term performance of fresh autologous pericardium for mitral valve leaflet repair.
      Our series corroborates this observation with no patients showing signs of calcification in the leaflet.

      Conclusions

      This approach is easily accessible technically and augments the surgeon's armamentarium, especially in young patients to avoid valve replacement. We have performed SRT in a totally endoscopic manner in the majority of the patients (55%) using a 3-port technique
      • Ito T.
      • Maekawa A.
      • Hoshino S.
      • Hayashi Y.
      • Sawaki S.
      • Yanagisawa J.
      • et al.
      Three-port (one incision plus two-port) endoscopic mitral valve surgery without robotic assistance.
      (Video 1) without any mortalities or major complications. We now routinely perform SRT with an endoscopic platform. Mitral valve reconstruction with the seamless patch technique provides an excellent midterm result when applied to the pathologies involving the commissure or up to 2 segments.

      Conflict of Interest Statement

      T.I. received a proctor fee from Edwards Lifescience, Inc, and a lecture fee from Medtronic, Inc, and Abbott, Inc (no direct conflict with this manuscript). All other authors reported no conflicts of interest.
      The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest.

      Supplementary Data

      • Video 1

        Totally 3-dimensional endoscopic mitral valve repair using SRT after converting the 2-dimensional view. A mitral valve repair for active endocarditis is shown. A 32-year-old man, previously diagnosed with moderate mitral valve regurgitation with anterior leaflet prolapse, presented with intractable fever after treatment for pyogenic spondylitis. Urgent surgery was carried out for the large vegetation after 1 week of antibiotic treatment. The infective tissue was found at the P3 to posterior commissure. After the debridement, a triangular-shaped autologous pericardium was prepared to cover the whole P3 to PC area. Myxomatous change in the anterior mitral leaflet was found and corrected with a loop technique. Video available at: https://www.jtcvs.org/article/S2666-2507(22)00529-6/fulltext.

      Appendix 1

      Figure thumbnail fx3
      Figure E1Freedom from reoperation after seamless patch mitral reconstruction in the commissural, up to 2-segment, and 3-segment involvement groups with competing risk of death and reoperation by the extent of leaflet involvement.
      Figure thumbnail fx4
      Figure E2Freedom from significant MR after seamless patch mitral reconstruction in the commissural, up to 2-segment, and 3-segment involvement groups with competing risk of death and reoperation by the extent of leaflet involvement. MR, Mitral regurgitation.
      Table E1Details of the mitral reinterventions
      Age, y, gender/reason for redo surgeryFindings in redo surgeryMonths from the index surgeryIndex procedureReoperation
      163 F/MRTorn patch9Double pentagon P1-2Replacement
      257 F/MRTorn patch5Double pentagon P1-3, A1-3Replacement
      366 F/MRTorn patch8Double triangle A1-3Replacement
      470 M/MRTorn patch/ring detachment27Double pentagon P1-3Replacement
      588 F/MRHemolysis7Pentagon, P1-3Re-repair
      683 F/MRSystolic anterior motion/hemolysis1Pentagon, P2-3Replacement
      767 F/MRUnknown8Double pentagon, A1-3Replacement
      869 F/MRRemnant leaflet sclerosis1Double pentagon, A1-3Replacement
      976 F/MSRemnant leaflet sclerosis91Pentagon, A2-3Replacement
      MR, Mitral regurgitation; MS, mitral stenosis.

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