Mitral Annular Forces and Their Potential Impact on Annuloplasty Ring Selection

Objectives: To provide an overview that describes the characteristics of a mitral annuloplasty device when treating patients with a specific type of mitral regurgitation according to Carpentier's classification of mitral regurgitation.Methods: Starting with the key search term “mitral valve annuloplasty,” a literature search was performed utilising PubMed, Google Scholar, and Web of Science to identify relevant studies. A systematic approach was used to assess all publications.Results: Mitral annuloplasty rings are traditionally categorised by their mechanical compliance in rigid-, semi-rigid-, and flexible rings. There is a direct correlation between remodelling capabilities and rigidity. Thus, a rigid annuloplasty ring will have the highest remodelling capability, while a flexible ring will have the lowest. Rigid- and semi-rigid rings can furthermore be divided into flat and saddled-shaped rings. Saddle-shaped rings are generally preferred over flat rings since they decrease annular and leaflet stress accumulation and provide superior leaflet coaptation. Finally, mitral annuloplasty rings can either be complete or partial.Conclusions: A downsized rigid- or semi-rigid ring is advantageous when higher remodelling capabilities are required to correct dilation of the mitral annulus, as seen in type I, type IIIa, and type IIIb mitral regurgitation. In type II mitral regurgitation, a normosized flexible ring might be sufficient and allow for a more physiological repair since there is no annular dilatation, which diminishes the need for remodelling capabilities. However, mitral annuloplasty ring selection should always be based on the specific morphology in each patient.

369 Mono-orifice mitral valve after transcatehter repair with mitraclip system

A 70 years old male with non-ischaemic dilated cardiomyopathy (left ventricular end-diastolic volume, LVEDV, 200 mL), reduced left ventricular ejection fraction (LVEF, 30%) and worsening dyspnoea was screened for transcatheter repair of severe mitral regurgitation (MR). Baseline echocardiogram showed marked symmetrical bi-leaflet tethering with a symmetrical central jet. Etiology was predominantly functional with organic features including partial flail scallop (A1) and a ruptured second order chorda (Figure 1A). Pre-operative strategy was to deploy a single MitraClip NT in the central position. After correct deployment of the first clip, we observed a remarkable reduction of regurgitant jets in the lateral position accompanied by a complete holosystolic lack of leaflet coaptation in the medial orifice which caused significant residual regurgitation. (Figure 1B) MitraClip deployment in the commissural position is associated with technical challenges, including limited maneuvering, risk of chordae rupture and inability to retrieve the device if entangled. (1) Therefore, after careful crossing of the medial neo-orifice and rapid positioning a second MitraClip NT was implanted medial to the first device in the commissural position (Figure 2). As a result, the medial orifice was obliterated resulting in an atypical mono-orifice morphology which resembles a commissural edge-to-edge plasty. Anterograde flow was normal (G med 2.5 mmHg) and the trivial residual jet of MR was lateral to the two clips implanted. At 1-year follow-up the patient was asymptomatic (NYHA functional class I) with a stable mild MR and no change in anterograde gradients; positive remodelling of the left ventricle (LVEDP: −48 ml) and increased LVEF (+8%) were observed. 369 Figure 1.

Transcatheter mitral valve repair using the Cardioband® system: Histopathological insights in device ingrowth and biocompatibility

Surgical implantation of a complete or incomplete ring to reduce the valve annulus and improve leaflet coaptation is the mainstay of mitral valve surgery. The Cardioband® system (Edwards Lifesciences, Irvine, CA, USA) was designed to address the pathophysiological mechanism of annular dilatation through a catheter-based approach. We present the histopathological workup of a Cardioband® device, which had been implanted 21 months earlier in a 34-year-old male with ischemic cardiomyopathy. Device examination demonstrate a well-positioned and securely anchored device. The described tissue reactions may have an impact on choice of device and timing in case of re-do surgery.

A Novel Transcatheter Edge-to-Edge Suturing Technique and Prototype for Repairing Tricuspid Valve Regurgitation

Tricuspid valve regurgitation is a major clinical issue that continues to attract interest from interventional cardiologists and medical device designers due to its rising prevalence and progressive nature. This disease impact is exacerbated among the aging population, considered as high risk of mortality for open-heart surgical procedures. Furthermore, early intervention for tricuspid regurgitation following left-sided heart procedures continues to increase. Thus, percutaneous or transcatheter interventions have emerged as the new frontier for tricuspid valve therapy. Specifically, tricuspid leaflet plication, or edge-to-edge repair, is a valvular procedure to enhance the coaptation of the leaflets and reduce regurgitation. The current landscape of approved transcatheter devices for leaflet coaptation are exclusive to the mitral valve or being investigated for tricuspid treatment. However, most of these transcatheter systems are designed with high procedure specificities, are expensive, and require extensive procedural training. Hence, there is an opportunity to percutaneously plicate the tricuspid leaflets using commonly available right-heart catheter equipment. This study details a novel transcatheter repair procedure that can plicate the tricuspid valve leaflets solely using current market released catheters and/or surgical equipment. Testing and evaluation of this prototype procedure was performed using Visible Heart® methodologies.

Epicardial Posterior Papillary Muscle Repositioning with Mitral Annular Reduction for FIMR Treatment: Initial Ex Vivo Heart Model Study

Background: High recurrent functional ischemic mitral regurgitation (FIMR) has been observed after annuloplasty. Since annuloplasty alone could not prevent late recurrent FIMR or improve the survival rate after CABG, adjunctive subvalvular opt for better treatment tailored for each individual patient. Methods: Ex vivo ovine heart models with annular dilatation and PPM displacement were used for analysis of mitral regurgitation (MR) flow, left ventricular and annular geometry after treatment by mitral annular reduction alone (MA, nMA = 12) or combined with epicardial PPM repositioning (MA+PPM, nMA+PPM=13). Results: MR significantly was reduced from baseline in both the MA (P = .03) and MA+PPM (P = .02) groups, but was not significantly different between the groups. The septo-lateral mitral annular distance decreased after applying both methods (MA group P = .005; MA+PPM group P = .05). The tethering α angle of the APM in the frontal plane significantly increased from baseline in the MA+PPM group (P = .027). Furthermore, the MA+PPM group had a larger APM and PPM α angle in the frontal plane compared with the MA group after reducing the MR (P = .04). There were no statistically significant changes in tethering angles found in the MA group compared with baseline. MR reduction correlated with percentage decrease of septo-lateral mitral annular distance (rs = 0.51, P = .01), the percentage decrease of fibrosa-PPM distance (rs = 0.43, P = .03), and the percentage increase of the PPM anterior displacement (rs = -0.41, P = .04). Conclusion: The decreased tethered angle of the PPM referred to the annulus, and the decreased interpapillary muscles distance suggested the PPM was repositioned inward and toward the septal annulus by the epicardial pushing pad. Epicardial repositioning of the PPM adjunct with mitral annular reduction facilitated leaflet coaptation without the risk of overlying restriction of the mitral annular orifice.

Functional and Degenerative Mitral Regurgitation: One Ring Fits All?

Background Three-dimensional saddle-shaped annuloplasty rings have been shown to create a larger surface of leaflet coaptation in mitral valve repair (MVR) for functional mitral regurgitation (FMR) and degenerative mitral regurgitation (DMR) which may increase repair durability. For the first time, this study reports mid-term results after MVR for DMR and FMR using a rigid three-dimensional ring (Profile 3D, Medtronic). Methods Between June 2009 and June 2012, 369 patients with DMR (n = 326) or FMR (n = 43) underwent MVR (mean age 62.3 ± 12.6 years). A total of 205 patients (55.6%) underwent isolated MVR and 164 patients (44.4%) a combined procedure. Follow-up examinations were performed in 94.9% (mean 4.9 ± 0.9 years). Echocardiographic assessment was complete in 93.2% (mean 4.3 ± 1.2 years). Results The 30-day mortality was 1.5% (5/326) for DMR (1.5% for isolated and 1.6% for combined procedures) and 9.3% (4/43) for FMR (0% for isolated and 10.5% for combined procedures). Survival at 6 years was 92.1 ± 1.9% for DMR (92.9 ± 2.6% for isolated and 90.7 ± 2.7% for combined procedures) and 66.4 ± 7.9% for FMR (80.0 ± 17.9% for isolated and 63.7 ± 8.9% for combined procedures). Cumulative risk for mitral valve-related reoperation at 6 years was 0% for FMR and 7.1 ± 1.5% for DMR. At echocardiographic follow-up, one patient presented with mitral regurgitation (MR) more than moderate. The only predictor of recurrent MR after MVR for DMR was residual mild MR at discharge. Conclusion Repair of FMR with the three-dimensional Profile 3D annuloplasty ring shows excellent mid-term results with regard to recurrence of MR. In cases of DMR, the results are conforming to the current literature.

Dynamic Modeling of Mitral Valve Annulus and Leaflet Coaptation by Splines

Visual and quantitative evaluation of the mitral valve is an important step in the clinicalworkflow according to experts as knowledge about mitral dynamics is crucial for interventionalplanning. We consider dynamic modeling of mitral valve annulus and leaflet coaptation by cubicB-splines, and the error of every tagging point is measured to the fitted curve to decide whether asecond round fitting is needed. After modeling, four clinically important points are identified. Thismodeling and identification are significantly important for further diagnosis and evaluation of thedynamic deformation of the mitral valve apparatus.