Midterm Results of the Edge-to-Edge Technique for Complex Mitral Valve Repair

Echocardiographic Evaluation of Successful Mitral Valve Repair or Need for a Second Pump Run in the Operating Room

Detailed preoperative and intraoperative echocardiographic assessment of the mitral valve apparatus is critical for a successful repair. The recent advent of 3-dimensional transesophageal echocardiography has added an extra pivotal role to transesophageal echocardiography in the assessment of mitral apparatus and mitral regurgitation. Because surgeons must rapidly decide whether cardiopulmonary bypass should be continued to be weaned off or a second pump run should be selected, the echocardiographer conducting intraoperative transesophageal echocardiography is required to be trained according to a certain algorithm. This review summarizes the current clinical role of intraoperative transesophageal echocardiography in mitral valve repair in the operating room.

Alfieri versus conventional repair for bileaflet mitral valve prolapse

Objective

Mitral valve repair for bileaflet prolapse can be complex, involving multiple chords or resection. The Alfieri technique for bileaflet disease is simple but may be associated with mitral stenosis or recurrent mitral regurgitation. Outcomes of patients with bileaflet prolapse undergoing mitral valve repair using the Alfieri versus conventional chord/resection techniques were compared.

Methods

Adults undergoing mitral valve repair for bileaflet prolapse for degenerative disease from 2017 to 2023 were stratified by repair technique. Outcomes including operative mortality and echocardiogram data were compared. Time to event analysis was used to characterize freedom from recurrent mitral regurgitation (moderate or greater mitral regurgitation).

Results

Among 188 patients with bileaflet prolapse, 37% (70) were repaired with the Alfieri and the remaining patients were repaired with chords/resection. Compared with chords/resection, patients undergoing the Alfieri had shorter cardiopulmonary bypass and crossclamp times. Operative mortality (0% [0/70] vs 2% [2/118], P = .27) was similar between both techniques. The mean mitral gradient was low and similar for the Alfieri versus chords/resection (3 vs 3, P = .34). Development of recurrent mitral regurgitation at 2 years, incorporating the competing risk of death and mitral reintervention, was 4.3% (95% CI, 1.5%-9.3%) for the Alfieri technique and 5.8% (95% CI, 2.2%-11.8%) for chord/resection (P = .83).

Conclusions

Both the Alfieri and chord/resection techniques had low rates of recurrent mitral regurgitation at 2 years. The mitral valve gradient was low and similar regardless of technique; thus, those who received the Alfieri technique did not have an increased rate of mitral stenosis. The Alfieri may be an underused technique for bileaflet prolapse.

Comparison of meta-analytical estimates of outcomes after Alfieri or neochordal repair in isolated anterior mitral prolapse

OBJECTIVES

Repair of the isolated degenerative anterior mitral leaflet has been considered more challenging and associated with compromised durability compared with isolated posterior leaflet in major series. Implantation of neochordae or Alfieri edge-to-edge is the most employed repair technique for isolated anterior repair currently, but little data exist comparing their relative durability. We sought to investigate this issue with this meta-analysis.

METHODS

A literature search was performed (Ovid MEDLINE, Ovid Embase and The Cochrane Library). The primary outcome was the incidence rate (IR) of reoperation, the secondary outcomes were recurrent moderately severe/severe mitral regurgitation (MR), in-hospital/30-day reoperation and mortality and follow-up mortality. A random-effect model was used. Leave-one-out, subgroup analysis (Alfieri versus neochordae) and meta-regression were done.

RESULTS

Seventeen studies (including 1358 patients) were included. At a weighted mean follow-up of 5.56 ± 3.31 years, the IR for reoperation was 14.45 event per 1000 person-year and significantly lower in Alfieri than neochordae repair (9.40 vs 18.61, P = 0.04) on subgroup analysis. The IR of follow-up moderately severe/severe MR was 19.89 event per 1000 person-year and significantly lower in Alfieri than neochordae repair (10.68 and 28.63, P = 0.01). In a sensitivity analysis comparing homogenous studies, a significant difference in the recurrence of regurgitation in favour of the Alfieri approach remained. There were no differences in operative outcomes or survival. There were significant associations between increased incidence of late reoperation and New York Heart Association class III/IV and associated coronary artery bypass graft procedure for whole cohort.

CONCLUSIONS

Alfieri repair may be associated with a lower incidence of recurrent MR compared with neochordae-based repair in the setting of isolated degenerative anterior mitral pathology. This is the first such meta-analysis and further inquiry into this area is needed.

Surgical edge-to-edge repair for tricuspid regurgitation: Impact of the concomitant annuloplasty

BACKGROUND

Surgical edge-to-edge repair has been suggested for tricuspid regurgitation (TR) with complex tricuspid valve (TV) pathologies. Nevertheless, the impact of concomitant TAP has not been well established. This study aimed to compare the outcomes of tricuspid edge-to-edge repair according to the implementation of concomitant TAP.

METHODS

A total of 264 patients who underwent tricuspid edge-to-edge repair between January 2001 and December 2020 were enrolled in the study, and 23 patients who had undergone previous TV repair were excluded. The remaining 241 patients were categorized into two groups: TAP (n = 190) and non-TAP (n = 51). Inverse probability of treatment weighting (IPTW) was used to adjust the baseline differences between the two groups.

RESULTS

Early mortality and morbidity did not differ between the two groups. The mean follow-up duration was 111.5 ± 72.4 months. IPTW-adjusted survival analysis did not reveal a difference between the two groups in late significant tricuspid stenosis (trans-tricuspid pressure gradient ≥5 mmHg) and TV reoperations. However, freedom from overall mortality and late severe TR were significantly higher in the TAP group (p = 0.033 and 0.006, respectively). The sensitivity analysis, including propensity score matching, showed consistent results.

CONCLUSION

The long-term outcomes of surgical tricuspid edge-to-edge repair were better when performed with concomitant TAP.

Modified Transventricular and Transaortic Mitral Valve Edge-to-Edge Repair Mimicking MitraClip Overcorrection

Objective

In the current study, we present our mid-term experience with modified edge-to-edge repair technique through a transventricular and transaortic route in patients requiring left ventricular remodeling or aortic root/valve surgery.

Methods

From December 2006 through April 2015, 49 high-risk patients (median age: 69 years; median European System for Cardiac Operative Risk Evaluation II: 11.4 [6.54-14.9]) underwent transventricular (N = 7; 14%) or transaortic (N = 42; 86%) edge-to-edge mitral valve repair. The Alfieri stitch technique was modified by MitraClip type overcorrection and solid buttressing behind the posterior leaflet. Indication was grade 2+ functional mitral valve incompetence and dilated or impaired left ventricle (N = 25; 52%), or grade 3+ (N = 22; 45%) and grade 4+ functional mitral valve regurgitation (N = 2; 4%). Surgical procedure included aortic root surgery in 65%, aortic valve replacement with surgical revascularization in 18%, and Dor-plasty with surgical revascularization in 14%.

Results

Intraoperative mortality and early neurologic complications were absent in our series. Ninety-day mortality was 12.2% (N = 6). Median clinical and echocardiographic follow-up-time was 50.7 (21.5-44.1) and 39.2 (33.7-44.1) months, respectively. Median postoperative transvalvular gradient was low (2.72 [1.91-4.22] mm Hg) and did not increase during follow-up (P = .268), although peak gradient rose slightly from 7.41 to 8.12 mm Hg (P = .071). The actuarial reoperation free rate at the index valve was 96.8%.

Conclusions

Transventricular or transaortic Alfieri mitral repair mimicking mitral clip overcorrection represents a quick and safe technique in the setting of high-risk patients undergoing left ventricular remodeling or aortic root/valve surgery and can be performed with low risk of creating mitral stenosis at midterm. The technique is straightforward, with reliable identification of the center of the valve leaflets being the limitation.

Echocardiographic Evaluation of Successful Mitral Valve Repair or Need for a Second Pump Run in the Operating Room

Detailed preoperative and intraoperative echocardiographic assessment of the mitral valve apparatus is critical for a successful repair. The recent advent of 3-dimensional transesophageal echocardiography has added an extra pivotal role to transesophageal echocardiography in the assessment of mitral apparatus and mitral regurgitation. Because surgeons must rapidly decide whether cardiopulmonary bypass should be continued to be weaned off or a second pump run should be selected, the echocardiographer conducting intraoperative transesophageal echocardiography is required to be trained according to a certain algorithm. This review summarizes the current clinical role of intraoperative transesophageal echocardiography in mitral valve repair in the operating room.

Long-term results of the edge-to-edge repair for failed mitral valve repair as a bailout option

OBJECTIVE

We evaluate the long-term clinical and echocardiographic outcomes of edge-to-edge (E2E) repair combined with mitral annuloplasty in our institute with degenerative mitral regurgitation (MR) up to 10 years.

METHODS

Twenty-six consecutive patients undergoing E2E mitral repair after failure of other conventional mitral repair technique. There were 16 (61.5%) male and the mean age was 52.2 ± 10.4 years. Mitral regurgitation was due to anterior leaflet prolapse in 12 (46.2%) patients, bileaflet prolapse in 9 (34.6%), and multiple segment posterior leaflet prolapse in 5 (19.2%).

RESULTS

There were no perioperative deaths. Follow-up was 100% complete. The mean length of follow-up was 8.7 ± 0.9 years (median 8.4 years, 6.8-10.1 years). Two patients required reoperation of the MV. The freedom from reoperation and ≥ Moderate MR at 10 years was 69.9 ± 11.7%. The freedom from reoperation, ≥ Moderate MR and mitral stenosis (MS) at 10 years was (59.6 ± 10.0) %. The mean transmitral pressure gradient (TMPG) was 6.1 ± 2.5 mmHg, which was significantly elevated compared with preoperative TTE (P = 0.004). The freedom from ≥ Moderate MS at 10 years was 76.9 ± 8.3%. There were no differences between patients with and without MS at follow-up regarding the echocardiographic parameters and clinical status.

CONCLUSION

There is a slowly progressive elevation of TMPG after E2E mitral repair, while mildly elevated TMPG can be tolerated in most patients. In appropriate patients, the E2E repair combined with annuloplasty provides an effective "bailout" choice.

A Novel 3-Dimensional Approach for the Echocardiographic Evaluation of Mitral Valve Area After Repair for Degenerative Disease

BACKGROUND

Currently available 2-dimensional (2D) echocardiographic methods for accurately assessing the mitral valve orifice area (MVA) after mitral valve repair (MVr) are limited due to its complex 3-dimensional (3D) geometry. We compared repaired MVAs obtained with commonly used 2D and 3D echocardiographic methods to a 3D orifice area (3DOA), which is a novel echocardiographic measurement and independent of geometric assumptions.

METHODS

Intraoperative 2D and 3D transesophageal echocardiography (TEE) images from 20 adult cardiac surgery patients who underwent MVr for mitral regurgitation obtained immediately after repair were retrospectively reviewed. MVAs obtained by pressure half-time (PHT), 2D planimetry (2DP), and 3D planimetry (3DP) were compared to those derived by 3DOA.

RESULTS

MVAs (mean value ± standard deviation [SD]) after MVr were obtained by PHT (3 ± 0.6 cm), 2DP (3.58 ± 0.75 cm), 3D planimetry (3DP; 2.78 ± 0.74 cm), and 3DOA (2.32 ± 0.76 cm). MVAs obtained by the 3DOA method were significantly smaller compared to those obtained by PHT (mean difference, 0.68 cm; P = .0003), 2DP (mean difference, 1.26 cm; P < .0001), and 3DP (mean difference, 0.46 cm; P = .003). In addition, MVA defined as an area ≤1.5 cm was identified by 3DOA in 2 patients and by 3DP in 1 patient.

CONCLUSIONS

Post-MVr MVAs obtained using the novel 3DOA method were significantly smaller than those obtained by conventional echocardiographic methods and may be consistent with a higher incidence of MVA reduction when compared to 2D techniques. Further studies are still needed to establish the clinical significance of 3D echocardiographic techniques used to measure MVA after MVr.

Evolution of the concept and practice of mitral valve repair

The first successful mitral valve repair was performed by Elliot Cutler at Brigham and Women's Hospital in 1923. Subsequent evolution in the surgical techniques as well as multi-disciplinary cooperation between cardiac surgeons, cardiologists and cardiac anesthesiologists has resulted in excellent outcomes. In spite of this, the etiology of mitral valve pathology ultimately determines the outcome of mitral valve repair.

Pre-operative systolic anterior motion of the mitral valve in a patient undergoing mitral valve repair

A patient with myxomatous mitral valve prolapse underwent mitral mitral valve repair due to severe symptomatic mitral regurgitation. Preoperative echocardiography demonstrated systolic anterior motion of the mitral valve. This finding disappeared once spontaneous chordal rupture occurred, resulting in a flail posterior mitral leaflet. As the patient was considered at high risk of developing post-repair SAM, he was operated on using surgical techniques aimed at lowering the risk of this complication. Despite this, post-repair SAM did develop and could only be eliminated by a surgical edge-to-edge (Alfieri) repair.

Intraoperative evaluation of transmitral pressure gradients after edge-to-edge mitral valve repair

Objective

Edge-to-edge repair of the mitral valve (MV) has been described as a viable option used for the surgical management of mitral regurgitation (MR). Based on the significant changes in MV geometry associated with this technique, we hypothesized that edge-to-edge MV repairs are associated with higher intraoperative transmitral pressure gradients (TMPG) compared to conventional methods.

Methods

Patient records and intraoperative transesophageal echocardiography (TEE) examinations of 552 consecutive patients undergoing MV repair at a single institution over a three year period were assessed. After separation from cardiopulmonary bypass (CPB), peak and mean TMPG were recorded for each patient and subsequently analyzed.

Results

84 patients (15%) underwent edge-to-edge MV repair. Peak and mean TMPG were significantly higher compared to gradients in patients undergoing conventional repairs: 10.7±0.5 mmHg vs 7.1±0.2 mmHg; P<0.0001 and 4.3±0.2 mmHg vs 2.8±0.1 mmHg; P<0.0001. Only patients with mean TMPG ≥7 mmHg (n = 9) required prompt reoperation for iatrogenic mitral stenosis (MS). No differences in peak and mean TMPG were observed among edge-to-edge repairs performed in isolation, compared to those performed in combination with annuloplasty: 11.0±0.7 mmHg vs 10.3±0.6 mmHg and 4.4±0.3 mmHg vs 4.3±0.3 mmHg. There were no differences in TMPG between various types of annuloplasty techniques used in combination with the edge-to-edge repairs.

Conclusions

Edge-to-edge MV repairs are associated with higher intraoperative peak and mean TMPG after separation from CPB compared to conventional repair techniques. Unless gradients are severely elevated, these findings are not necessarily suggestive of iatrogenic MS. Thus, in the immediate postoperative period mildly elevated TMPG can be expected and tolerated after edge-to-edge mitral repairs.

Alfieri repair for post-repair mitral systolic anterior motion in a young child

An 11-year-old patient with Marfan syndrome presented with severe mitral and tricuspid regurgitation and underwent mitral valve repair consisting of a vertical folding plasty of a redundant and prolapsing A1, closure of a deep cleft-like A1-A2 indentation, and annuloplasty to 28 mm, and tricuspid valve repair. Post-bypass echocardiography showed significant systolic anterior motion of the mitral valve. The annuloplasty was upsized to 34 mm and the A1 folding plasty taken down. Echocardiography showed persistent systolic anterior motion. An edge-to-edge repair was placed at A1-P1, eliminating all systolic anterior motion. The patient had an uneventful postoperative course and 6-week follow-up.

Early Results of Edge-to-Edge Alfieri Mitral Repair Via Right Mini-Thoracotomy in 68 Consecutive Patients

OBJECTIVE

: To examine early outcomes of mitral valve repair using Alfieri repair via a right mini-thoracotomy approach.

METHODS

: Records were examined in 68 consecutive patients undergoing Alfieri mitral repair via 6 cm right mini-thoracotomy. Most repairs were performed under cardioplegic arrest, using percutaneous femoral cannulation and direct aortic cannulation through the right first intercostal space. All patients without hypertrophic cardiomyopathy received rigid ring annuloplasty. The indications for Alfieri repair were extensive prolapse with ring size at least 30 mm.

RESULTS

: Mean age was 56 ± 13 (range, 20-80). Mitral disease etiology was Barlow disease in 17 of 68 (25%) patients and myxomatous disease in 47 of 68 (69%). Concurrent procedures were performed in 29 of 68 (43%) patients. Median ring size was 34 mm. Despite extensive leaflet disease, 59 of 68 (87%) patients were repaired without leaflet resection. Chord pairs were inserted on the posterior leaflet in 18 of 68 (26%) patients and anterior leaflet in four patients. There were no 30-day or late deaths. Residual intraoperative mitral regurgitation was absent in 54 of 68 (79%) patients and trace in the remainder. Local echocardiography follow-up at a mean of 99 days showed median residual regurgitation to be trace. Only two patients developed moderate regurgitation. Mean mitral gradient at follow-up was 4 ± 2 mm Hg. Local follow-up showed 28 of 39 (72%) patients to be New York Heart Association class I.

CONCLUSIONS

: An edge-to-edge Alfieri repair via mini-thoracotomy can provide excellent short-term results in selected patients with complex myxomatous mitral disease when minimizing the need for leaflet resection.

Transaortic edge-to-edge mitral valve repair and left ventricular myectomy

Systolic anterior motion of mitral anterior leaflet is a serious clinical condition and it is hard to control medically. Alfieri edge-to-edge repair has been thought one of the useful techniques to improve abnormal anterior systolic motion with hypertrophic obstructive cardiomyopathy. Here, we present a 71-year-old lady who had the left ventricular outflow tract obstruction, severe mitral valve regurgitation with systolic anterior motion. The patient had a history of aortic valve replacement 5 years ago. She was successfully treated with transaortic edge-to-edge mitral valve plasty and myectomy of the left ventricle. Postoperative course was uneventful.

Asymmetric Alfieri's stitch to correct systolic anterior motion after mitral valve repair

Systolic anterior motion of the mitral valve is a feared complication after valve repair, with important implications in the postoperative period. Provocation with isoproterenol is valuable in the assessment of its mechanism and severity in high-risk patients. Surgical correction of this condition is sometimes difficult and may require valve replacement. We present a modification of Alfieri's edge-to-edge technique that adapts better to the mechanism of systolic anterior motion (SAM) after mitral repair in selected patients by placing the edge-to-edge suture between the A1-P1 segments and not in the midline.

Need for new materials, biofunctionalization and non-surgical heart valve technology

Transition from non-surgical heart valve defects repair from bench to bedside is a reality. Some biological material-based designs for transcatheter aortic valve implantation are ready for use. Their drawback, however is their unknown functional as well as structural durability. Moreover, research on new non-biological materials is essential to replace classical animal-derived sources of human heart valve prostheses.

Hemodynamics of the Mitral Valve Under Edge-to-Edge Repair: An In Vitro Steady Flow Study

Edge-to-edge repair (ETER) is a mitral valve repair technique that restores valvular competence by suturing together the free edges of two leaflets. This repair technique alters mitral valve inflow and thus left ventricle hemodynamics during diastole. Our objective was to investigate fluid mechanics immediately downstream of the mitral valve under ETER during diastole. Fresh porcine mitral valves of the annulus size M32 with chordae removed were installed into a steady flow loop simulating a peak diastolic inflow through the mitral valve. Digital particle image velocimetry was used to measure the velocity field immediately downstream of the mitral valve under normal and ETER conditions. First, to study the suture length effect, suture was applied in the central position of the leaflet edge with suture lengths of 3 mm, 6 mm, and 9 mm, respectively. Then, 3 mm suture was set in the central, lateral, and commissural positions of the leaflet edge to study the suture position effect. Flow rate was 15 l/min. Velocity, Reynolds shear stress (RSS), and effective orifice area were assessed. A total of five mitral valves were tested. The normal mitral valve without the ETER had one jet downstream of the valve, but the mitral valve with the central or lateral sutures under the ETER had two jets downstream of the valve with a recirculation region downstream of the suture. The maximum velocity, the maximum RSS in the jets, the pressure drop across the mitral valve, and the jet deflection angle increased with the increase in suture length in the central position. When the suture position effect was investigated with the 3 mm suture, the maximum velocity, the maximum RSS, and the pressure drop across the valve in the central suture position were greater than those of the lateral and the commissural suture positions. The lateral suture demonstrated major and minor jets with the greater maximum velocity and maximum RSS in the major jet. When the suture was in the commissural position, the flow field downstream of the mitral valve was similar to that of the normal mitral valve without the ETER. The effective orifice area was smallest when the suture was applied in the central position as compared with other suture positions. Both suture length and position have an important impact on fluid mechanics downstream of the mitral valve under the ETER in terms of flow pattern, maximum velocity, and RSS distribution. The altered hemodynamics of the mitral valve and thus of the left ventricle by the ETER may change mitral valve and left ventricle function.