Advances in Mitral Valve Repair for Degenerative Mitral Regurgitation: Philosophy, Technical Details, and Long-Term Results

Proof of Concept: Development of a Mitral Annuloplasty Ring With Crosshatch Net

OBJECTIVE

Here we report our preclinical, proof-of-concept testing to assess the ability of a novel device to correct mitral regurgitation. The Milwaukee Heart device aims to enable any cardiac surgeon to perform high-quality mitral valve repair using a standard annuloplasty ring with a crosshatch of microporous, monofilament suture.

METHODS

Hemodynamic, echocardiographic, and videographic data were collected at baseline, following induction of mitral regurgitation, and after repair using porcine hearts in an ex vivo biosimulator model. A commercially available cardiac prosthesis assessment platform was then used to assess the hydrodynamic characteristics of the study device.

RESULTS

Porcine biosimulator pressure and flow metrics exhibited successful correction of mitral regurgitation following device implantation with similar values to baseline. Hydrodynamic results yielded pressure gradients and an effective orifice area comparable to currently approved prostheses.

CONCLUSIONS

The study device effectively reduced mitral valve regurgitation and improved hemodynamics in our preclinical model with similar biophysical metrics to currently approved devices. Future in vivo trials are needed to evaluate the efficacy, biocompatibility, and freedom from the most likely adverse events, such as device thrombosis, embolic events, and hemolysis.

Mitral valvuloplasty using real-time three-dimensional transesophageal echocardiography

OBJECTIVE

This study aimed to investigate the structure of the mitral valve in patients undergoing mitral valvuloplasty (MVP) using real-time three-dimensional transesophageal echocardiography (RT-3D-TEE). The main objective was to study the relationship between intraoperative annuloplasty ring size and mitral valve structure dimensions, with a focus on exploring the application value of RT-3D-TEE in MVP.

METHODS

A total of 28 patients with degenerative mitral regurgitation (DMR), who underwent MVP between February and September 2022, as well as 12 normal control cases, were enrolled in this study. The MV annulus and leaflets were quantitatively analyzed using MVN software.

RESULTS

The DMR group exhibited significantly greater dimensions in various parameters of the mitral valve, including the anterolateral-to-posteromedial diameter (DAlPm ), anterior-to-posterior diameter (DAP ), annulus height (HA ), three-dimensional annulus circumference (CA3D ), two-dimensional annulus area (AA2D ), anterior leaflet area (Aant ), posterior leaflet area (Apost ), anterior leaflet length (Lant ), posterior leaflet length (Lpost ), and tenting volume (Vtent ) compared to the control group.

CONCLUSION

Real-time three-dimensional transesophageal echocardiography provides valuable insights into the morphological structure of the mitral valve and lesion location. It can aid in surgical decision-making, validate the success of MVP, and potentially reduce mortality and complications associated with mitral valve repair procedures.

The evolution of technical prerequisites and local boundary conditions for optimization of mitral valve interventions-Emphasis on skills development and institutional risk performance

This viewpoint report describes how the evolution of transcatheter mitral valve intervention (TMVI) is influenced by lessons learned from three evolutionary tracks: (1) the development of treatment from mitral valve surgery (MVS) to transcutaneous procedures; (2) the evolution of biomedical engineering for research and development resulting in predictable and safe clinical use; (3) the adaptation to local conditions, impact of transcatheter aortic valve replacement (TAVR) experience and creation of infrastructure for skills development and risk management. Thanks to developments in computer science and biostatistics, an increasing number of reports regarding clinical safety and effectiveness is generated. A full toolbox of techniques, devices and support technology is now available, especially in surgery. There is no doubt that the injury associated with a minimally invasive access reduces perioperative risks, but it may affect the effectiveness of the treatment due to incomplete correction. Based on literature, solutions and performance standards are formulated with an emphasis in technology and positive outcome. Despite references to Heart Team decision making, boundary conditions such as hospital infrastructure, caseload, skills training and perioperative risk management remain underexposed. The role of Biomedical Engineering is exclusively defined by the Research and Development (R&D) cycle including the impact of human factor engineering (HFE). Feasibility studies generate estimations of strengths and safety limitations. Usability testing reveals user friendliness and safety margins of clinical use. Apart from a certification requirement, this information should have an impact on the definition of necessary skills levels and consequent required training. Physicians Preference Testing (PPT) and use of a biosimulator are recommended. The example of the interaction between two Amsterdam heart centers describes the evolution of a professional ecosystem that can facilitate innovation. Adaptation to local conditions in terms of infrastructure, referrals and reimbursement, appears essential for the evolution of a complete mitral valve disease management program. Efficacy of institutional risk management performance (IRMP) and sufficient team skills should be embedded in an appropriate infrastructure that enables scale and offers complete and safe solutions for mitral valve disease. The longstanding evolution of mitral valve therapies is the result of working devices embedded in an ecosystem focused on developing skills and effective risk management actions.

Mitral degenerative valve leaflets suspected as primary valvular tumor: a case report

BACKGROUND

Echocardiography plays an important role in the diagnosis of heart disease. Sometimes, however, it may also provide misdiagnosis information.

CASE PRESENTATION

We report a rare case of a misdiagnosis of primary mitral valvular tumor with severe regurgitation by preoperative echocardiography. During the surgery, the true lesion was found to be mitral valve leaflet prolapse due to degenerative mitral valve disease.

CONCLUSION

For individual patient, the best clinical decision not only needs the extensive application of echocardiography, but also needs the combination of clinical symptoms and more auxiliary examination.

Simple and Safe: Inverse Plication of the Posterior Mitral Leaflet in Everyday Mitral Valve Reconstruction with and without Concomitant Procedures

Objective: Cardiosurgical mitral valve repair (MVR) cannot be easily replaced by other interventional procedures due to the complexity of mitral valve regurgitation as well as physiologic and anatomic repair techniques. A wide variety of techniques have been adopted for proper reconstruction of posterior leaflet prolapse. We investigated the long-term results of quadrangular resections and compared them with a simplified reconstruction maneuver, the inverse plication. Methods: We retrospectively collected data from 1977 patients after mitral valve repair between 2004 and 2022. After considering inclusion and exclusion criteria, we analyzed data from 180 patients after MVR with and without concomitant procedures such as CABG and/or aortic valve replacement (AVR). All MVRs were performed with a semi-rigid annuloplasty ring. A total of 180 patients received quadrangular resection (QuadRes, N = 120)) or inverse plication (InvPlic, N = 60) of the posterior leaflet, among other measures. Demographic data, risk factors, procedure times, hospitalization time, early and long-term mortality as well as Kaplan-Meier survival were analyzed. Results: Age (65.3 vs. 63.1 years) and sex (28.8% female vs. 337.5% female) did not differ significantly, and the EuroSCORE was significantly higher in the InvPlic group (6.46 ± 2.75) than in the QuadRes group (5.68 ± 3.1). Procedural times did not differ for cardiopulmonary bypass, and were as follows: InvPlic 136 ± 44 min; QuadRes 140 ± 48 min; X-Clamp: InvPlic 91 ± 31 min; QuadRes 90 ± 32 min. Hospitalization time was slightly but insignificantly lower in the InvPlic group (15.5 days) than in the QuadRes group (16.1 days). Early mortality (5.08% vs. 8.33%) and re-do procedures (1.69% InvPlic; 6.67% QuadRes) did not differ significantly. However, long-term mortality was significantly lower in the InvPlic group (15.25% vs. 32.32%, p = 0.029). Conclusions: Among the surgical measures for the posterior leaflet, inverse plication appears to be non-inferior to quadrangular resection in unselected all-comer patients. Long-term results and absence of re-do procedures indicate very good stability. Thus, inverse plication not only allows correction of PML, but is also completely safe in the long term and can replace quadrangular resection, especially in patients where a reduction in technical challenges and procedure duration is desired.

Comparison of early and late postoperative outcomes between chordal reconstruction and quadrangular resection in patients with posterior mitral valve prolapse: a single-center retrospective study

BACKGROUND

To compare the early and late postoperative outcomes of chordal reconstruction (CR) and quadrangular resection (QR) in patients with posterior mitral valve prolapse (PMPL).

METHODS

Between January 2008 and December 2018, 305 patients with PMPL who underwent mitral valve plasty (MVP) were included in this retrospective analysis. The CR and QR procedures were performed in 169 patients (CR group) and 136 patients (QR group), respectively. Early and late postoperative outcomes were compared between the groups.

RESULTS

Follow-up was complete in 96.4% (294/305) of patients, with a mean follow-up of 81.2 ± 30.4 months. No 30-day mortality was observed in any of the patients. The success rate of the mitral valve repair was similar in both groups (99.4% vs. 98.5%, P = 0.850). The incidence of early postoperative hemolysis was lower in the CR group than in the QR group (0.00% vs. 3.0%, P = 0.024). Postoperative left ventricular end-diastolic diameter (LVEDD) decreased more significantly in the CR group than in the QR group at 3 months (8.15 [1.30,12.65] vs. 3.25 [- 0.05, 8.75] mm, P < 0.001). During follow-up, the overall survival rates were 95.1% and 94.6% in the CR and QR groups, respectively. The incidence of reoperation for moderate or severe mitral regurgitation (MR) was similar in both groups (4.3% vs.5.4%, P = 0.653), but the time interval between the initial operation and reoperation was shorter in the QR group than in the CR group (84.3 ± 36.1 vs. 120.9 ± 27.6 months, P = 0.026). The LVEDD enlargement was more significant in the QR group than in the CR group (4.5 [3.6, 4.5] vs. 2.4 [1.3, 2.8] mm, P < 0.001).

CONCLUSION

CR and QR are effective techniques for patients with PMPL. Both techniques resulted in a low incidence of recurrent MR. However, CR can reduce early postoperative hemolysis and LVEDD more significantly. During the long-term follow-up, reoperations due to recurrent MR were performed at a longer interval after the initial operation. LVEDD expansion was better avoided in the CR group.