3 Committee discussion

The interventional procedures advisory committee considered evidence on off-pump minimal access mitral valve repair by artificial chordae insertion from several sources. This included evidence submitted by NeoChord, a review of efficacy and safety evidence, and responses from stakeholders. Full details are available in the project documents for this guidance.

NICE did a rapid review of the literature on the efficacy and safety of this procedure. The evidence included 7 prospective case series, 3 retrospective registry studies, 3 retrospective cohort studies, 2 retrospective case series and 2 case reports. It is presented in the summary of key evidence section in the interventional procedures assessment report. Other relevant literature is in the appendix of the assessment report. The evidence informing this guidance was from only 1 device. This is the only device currently used for this procedure in the UK.

The condition

3.1

The mitral valve allows blood to flow from the left atrium to the left ventricle. Mitral regurgitation happens when the valve does not close properly, allowing blood to flow back into the atrium from the ventricle during systole (when the heart contracts). The heart must work harder, resulting in an enlarged left ventricle. If untreated, this can lead to problems such as heart failure. Mitral regurgitation can be degenerative (primary or structural) or functional (secondary). Degenerative mitral regurgitation is caused by 'wear and tear' to the chordae and leaflets in the valve. In functional mitral regurgitation the chordae and leaflets are structurally normal but there is geometrical distortion of the subvalvular apparatus. This is caused by idiopathic cardiomyopathy or weakening of the cardiac walls because of coronary artery disease (ischaemic mitral regurgitation).

Current practice

3.2

Degenerative mitral regurgitation is typically managed with open-heart surgery to repair or replace the mitral valve. This requires a sternotomy to access the heart and the use of cardiopulmonary bypass. Functional mitral regurgitation can be managed conservatively with medical treatments for heart failure, but this approach is not curative. Surgical procedures such as undersized annuloplasty may also be an option. People with mitral regurgitation of either cause are usually older (typically over 70 years) and frailer, with multiple comorbidities.

Unmet need

3.3

Open-heart surgery may pose excessive risks for some people, particularly those who are older, frailer, or who have multiple or complex comorbidities. For people for whom open-heart surgery is prohibitively high risk, minimal access surgical approaches have been developed, such as artificial chordae insertion. These procedures can often be done through smaller incisions and without the need to stop the heart or use cardiopulmonary bypass. These options aim to reduce perioperative risk and improve recovery, although they may not be suitable for all anatomical presentations of mitral valve prolapse that cause mitral regurgitation.

The evidence

3.4

The professional experts and the committee considered the key efficacy outcomes to be:

quality of life
patient-reported outcomes
survival
mitral regurgitation grade reduction
echocardiographic outcomes.

3.5

The professional experts and the committee considered the key safety outcomes to be:

conversion to open-heart surgery
mortality
cardiovascular and cerebrovascular adverse events
sepsis
bleeding
pericardial and pleural effusion
kidney injury
heart rhythm conduction disturbances.

3.6

Patient commentary was sought but none was received.

Committee comments

3.7

The committee noted that if this procedure fails it does not preclude the use of further interventions. This procedure can also be used in people who have already had open-heart surgery.

3.8

Published evidence focused on process outcomes (such as procedural and technical success), with signals of efficacy not as strong.

3.9

A clinical expert emphasised the importance of mitral regurgitation reduction and echocardiographic outcomes associated with this procedure.

3.10

The committee noted the importance of an experienced multidisciplinary team being involved in decisions about suitability of this procedure or other procedures, including open-heart surgery. The team should include a cardiac surgeon and a 2D and 3D transoesophageal echocardiography operator with experience of this procedure. It also noted the need for proctoring to assist surgeons who are new to the procedure. Centres should follow any proctoring and training requirements associated with the device used.

3.11

This procedure should only be done by cardiac surgeons because of the need for thoracotomy, the risk of bleeding and the potential for urgent conversion to open-heart surgery with sternotomy.

3.12

A clinical expert noted that an isolated P2 prolapse is associated with the best outcomes for this procedure. For more complex anatomy, the experience of the surgeon must be taken into account when considering this procedure.

3.13

The committee noted that there is currently only 1 device used for this procedure in the UK. It also noted that the company reviews transoesophageal echocardiograms for every person who will have the procedure during the proctoring period and is available to provide advice about the procedure's technical feasibility.

3.14

The committee heard that this procedure may be a useful option for people who need re-repair because it avoids open-heart surgery. The committee noted that the evidence for the use of this procedure for re-repair is very limited and uncertain, and based on a carefully selected population. It acknowledged the need for targeted evidence collection to better identify the re-repair population, and to understand the size and balance of potential benefits and harms of the procedure in this group.

Equality considerations

3.15

The prevalence of mitral regurgitation increases with age.

3.16

The prevalence of valvular disease is similar in men and women.

3.17

The committee acknowledged that open-heart surgery and other mitral valve procedures may not be suitable for people who are older, frailer, or who have multiple or complex comorbidities. This procedure provides a treatment option for this group.

3.18

People with degenerative mitral valve disease may be considered disabled under the Equality Act 2010 if their condition has a substantial adverse impact on normal day-to-day activities for longer than 12 months.