MitraClip: an innovation for mitral regurgitation

In a normally functioning mitral valve, blood flows in a single direction from the left atrium to the left ventricle. Mitral regurgitation (MR) results from a lack of leaflet coaptation between the two leaflets of the mitral valve during the ventricular contraction. As a consequence, part of the ejected blood volume regurgitates to the left atrium. MR occurs when the mitral valve (for example, the leaflets), or one or more of the supporting structures, becomes damaged or dysfunctional. 

Moderate-to-severe MR is associated with an increased mortality: Estimates for one-year mortality among patients with severe MR range from 7.3% to 57%.(1) Mitral regurgitation progresses to heart failure and affects approximately one in ten people aged over 75 years.(2)

Mitral regurgitation is the most common type of heart valve insufficiency in the US:(2) 

 

Inspired by the Alfieri surgical edge-to-edge technique for mitral valve repair, the MitraClip system is the first-of-its-kind percutaneous mitral valve repair system for the treatment of moderate-to-severe or severe MR.

The MitraClip device received a CE Mark in 2008. In 2011, results from the landmark EVEREST II randomised control trial were published in the New England Journal of Medicine and, in 2012, MitraClip was recommended in the 2012 European Society of Cardiology (ESC) guidelines on management of valvular heart disease, indicating that the percutaneous edge-to-edge procedure may be considered in high-risk MR patients fulfilling the echo criteria. 

MitraClip is utilised during a percutaneous repair procedure (as opposed to open heart surgery offered by conventional surgery). The system allows physicians to conduct real-time MR assessment in the beating heart and to reposition the device multiple times until the desired reduction in MR is obtained.

• While the patient is under general anaesthesia, the clip is introduced percutaneously into the body through the femoral vein followed by trans-septal access to the mitral valve
• Mitral valve leaflets are grasped and coapted, resulting in a double orifice valve
• MR reduction is assessed with real-time trans-oesophageal echocardiography (two- or three-dimensional) to obtain optimal outcome
• The procedure neither requires arresting the heart nor cardiopulmonary bypass.

• The MitraClip procedure has the potential to be a valid treatment option for selected patients with significant MR. In particular, based on the current evidence, high-risk symptomatic, or otherwise inoperable patients with severe MR (organic or functional), seem the best candidates for the MitraClip, whenever the echocardiographic criteria of eligibility are met.(3) 
• Patient screening and selection are essential to the success of the procedure.

Abbott Vascular is committed to a multidisciplinary approach in order to optimise the quality of care and to support heart teams:

• A two-day training course followed by onsite support and expertise sharing from European centres of excellence are offered to the implanting team before the start-up of the program in their institution.
• The heart team comprises:

• To capitalise on the initial training and the learning curve of the team(4) and to try to maintain safety and therapeutic effectiveness, a minimum of two-to-three procedures per month is recommended
• Procedures are supported by experienced proctors.

At present, more than 7000 patients(5) have been treated with the MitraClip system worldwide and the body of clinical data and published articles (>210) continues to grow.

One-year follow-up results from ACCESS EU – real world registry in Europe on 567 patients – were presented at the ESC 2012 Congress.(6) More than half the patients in ACCESS-EU had an ejection fraction <40%, and 85% had NYHA class III or IV (Maisano et al, ACC 2012). Positive outcomes have been observed in multiple published cohorts. A critical observation from the real world registries was a shift from the EVEREST II patient population of primarily degenerative, surgical candidates toward mostly functional (77%), high surgical risk patients.

Several European implanters have published results(7–9) in patients with end-stage systolic heart failure (HF), and high STS and EuroSCORE. Their preliminary results with MitraClip system demonstrate significant reductions in MR, improvements in NYHA functional class, walk tests and pro-BNP levels.

Abbott Vascular is committed to pursuing the development of strong evidence demonstrating further the value of the therapy and supporting reimbursement efforts. Indeed, RESHAPE-HF, a large multicentre, randomised clinical trial, will enroll more than 800 patients in Europe to compare the clinical and economic value of MitraClip in patients with MR associated with heart failure to medical management.

MR is often associated with heart failure, which is one of the most common cardiovascular disorders worldwide and poses a significant economic burden(10) In the US, the estimated annual cost of heart failure in 2010 was $39.2 billion or ~2% of the total US healthcare budget. The main cost drivers of heart failure are hospitalisation, nursing home care, home health care and medications.

Hospitalisations account for approximately 60% of total heart failure costs in the US. Current therapeutic options include medical management, surgical repair or replacement and percutaneous interventions.

A significant reduction in the postprocedural hospital length of stay has been shown in the EVEREST II RCT. The average length of stay for the MitraClip group in the EVEREST randomised trial in surgical candidates was 2.6 days versus 7.5 days in the surgical control group. In the EVEREST II High Risk study, the average length of stay was three days for MitraClip patients. In the European ACCESS-EU cohort, the reported average length of stay was 7.7 days.(5,6)

Recipients of MitraClip are less likely to require home care or nurse rehabilitation post valve repair as home discharge is indicated in most cases.

A preliminary economic model (a ten-year UK-based cost-utility analysis) shows that MitraClip is a cost-effective treatment option for individuals with MR who are currently ineligible for surgical repair or replacement.(11)

Currently, the MitraClip is available for use in 15 European countries as well as in several other geographies (Australia, Asia, Middle-East and Canada). Reimbursement has been obtained in several countries, as, for example, in Germany where MitraClip is covered through DRG F98Z (Complex Mini-invasive Heart Valve procedures), Switzerland and Turkey.

1. Cioffi G et al. Functional mitral regurgitation predicts 1-year mortality in elderly patients with systolic chronic heart failure. Eur J Heart Fail 2005;7(7):1112–7.
2. American Heart Association. Heart disease and stroke statistics. Dallas, TX; 2003.
3. van den Heuvel A, Alfieri O, Mariani M. MitraClip in end-stage heart failure: a realistic alternative to surgery? Eur J Heart Fail 2011;13:472–4.
4. Schillinger W et al. Impact of the learning curve on outcomes after percutaneous mitral valve repair with MitraClip and lessons learned after the first 75 consecutive patients? Eur J Heart Fail 2011;13(12):1331–9.
5. Data on file: Abbott Vascular.
6. Schillinger, W. A post market study of the MitraClip System for the treament of significant MR in Europe: Analysis of outcomes at 1 year. ESC 2012; 25–29 August, Munich. 
7. Franzen O et al. MitraClip(R) therapy in patients with end-stage systolic heart failure. Eur J Heart Fail 2011;13(5):569–76.
8. Sven T et al. Acute safety and 30-day outcome after percutaneous edge-to-edge repair of mitral regurgitation in very high-risk patients, Am J Cardiol 2011;108(10):1478–82.
9. Treede H et al. A heart team’s perspective on interventional mitral valve repair: percutaneous clip implantation as an important adjunct to a surgical mitral valve program for treatment of high-risk patients. J Thorac Cardiovasc Surg 2011;143(1):78–84. 
10. Braunschweig F, Cowie MR, Auricchio A. What are the costs of heart failure? Europace 2011.
11. Mealing S et al. MitraClip for patients with mitral regurgitation who are ineligible for surgical repair: a UK based cost-utility analysis. Transcatheter Cardiovascular Therapeutics Annual Conference, November 2011; San Francisco, CA.