Percutaneous mitral valve annuloplasty - interventional procedures consultation document
NATIONAL INSTITUTE FOR HEALTH AND CLINICAL EXCELLENCE
Interventional procedure consultation document
Percutaneous mitral valve annuloplasty
Mitral regurgitation occurs when one of the four valves in the heart – the mitral valve – does not close properly, allowing blood to leak backwards. It may lead to shortness of breath and eventually heart failure (where the heart cannot pump enough blood to meet the body’s needs). In this procedure, a catheter is inserted into a large vein in the groin or neck and passed through to the heart. A device is placed into a large vein that sits next to the mitral valve to constrict the valve, with the aim of making it close properly.
The National Institute for Health and Clinical Excellence (NICE) is examining percutaneous mitral valve annuloplasty and will publish guidance on its safety and efficacy to the NHS in England, Wales, Scotland and Northern Ireland. NICE’s Interventional Procedures Advisory Committee has considered the available evidence and the views of Specialist Advisers, who are consultants with knowledge of the procedure. The Advisory Committee has made provisional recommendations about percutaneous mitral valve annuloplasty.
This document summarises the procedure and sets out the provisional recommendations made by the Advisory Committee. It has been prepared for public consultation. The Advisory Committee particularly welcomes:
· comments on the provisional recommendations
· the identification of factual inaccuracies
· additional relevant evidence, with bibliographic references where possible.
Note that this document is not NICE’s formal guidance on this procedure. The recommendations are provisional and may change after consultation.
The process that NICE will follow after the consultation period ends is as follows.
· The Advisory Committee will meet again to consider the original evidence and its provisional recommendations in the light of the comments received during consultation.
· The Advisory Committee will then prepare draft guidance which will be the basis for NICE’s guidance on the use of the procedure in the NHS in England, Wales, Scotland and Northern Ireland.
For further details, see the Interventional Procedures Programme manual, which is available from the NICE website (www.nice.org.uk/ipprogrammemanual).
NICE is committed to promoting through its guidance race and disability equality and equality between men and women, and to eliminating all forms of discrimination. One of the ways we do this is by trying to involve as wide a range of people and interest groups as possible in the development of our guidance on interventional procedures. In particular, we aim to encourage people and organisations from groups in the population who might not normally comment on our guidance to do so. We also ask consultees to highlight any ways in which draft guidance fails to promote equality or tackle discrimination and give suggestions for how it might be improved. NICE reserves the right to summarise and edit comments received during consultations, or not to publish them at all, where in the reasonable opinion of NICE, the comments are voluminous, publication would be unlawful or publication would otherwise be inappropriate.
Closing date for comments: 22 April 2010
Target date for publication of guidance: July 2010
1 Provisional recommendations
1.1 Current evidence on the safety and efficacy of percutaneous mitral valve annuloplasty is inadequate in quality and quantity. Therefore, this procedure should only be used in the context of research, which should clearly describe patient selection, concomitant medical therapies and safety outcomes. Both objective measurements and clinical outcomes should be reported.
1.2 Percutaneous mitral valve annuloplasty should only be carried out by interventional cardiologists with specific training in the procedure.
1.3 NICE may review the procedure on publication of further evidence.
2 The procedure
2.1 Indications and current treatments
2.1.1 Mitral regurgitation is characterised by backward flow of blood from the left ventricle to the left atrium during systole. Causes include rheumatic heart disease and annular dilation as a result of cardiomyopathy. Left untreated, moderate to severe mitral regurgitation can cause progressive congestive heart failure and eventually lead to death. Its severity is usually graded by echocardiography on a scale from grade 1 (mild) to grade 4 (severe).
2.1.2 Mitral regurgitation results from failure of apposition of the mitral valve leaflets, which may be due to abnormalities of the mitral leaflets themselves or their support apparatus, or from dilation of the mitral annulus. Dilation of the mitral annulus is usually a consequence of left ventricular enlargement and is considered to be ‘functional’ in aetiology.
2.1.3 Treatment of severe mitral regurgitation may include surgical placement of a supporting ring around the base of the mitral valve to reduce annular dilation (annuloplasty), bringing the mitral valve cusps closer together so that valve competence can be restored.
2.2 Outline of the procedure
2.2.1 The aim of percutaneous mitral valve annuloplasty is to place an intravascular device percutaneously into the coronary sinus to reduce its diameter when contracted and allow approximation of the valve leaflets.
2.2.2 The procedure is carried out with the patient under general or local anaesthesia. Under fluoroscopic and transoesophageal echocardiographic guidance, the device is advanced on a catheter via the femoral or jugular vein towards the coronary sinus. It is deployed and anchored in the coronary sinus. Residual mitral regurgitation is assessed and further percutaneous manipulation of the device may be used to reduce mitral regurgitation by changing the shape and size of the mitral valve annulus.
2.2.3 Various devices can be used for this procedure.
| Sections 2.3 and 2.4 describe efficacy and safety outcomes from the published literature that the Committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the overview, available at www.nice.org.uk/IP739overview. |
2.3 Efficacy
2.3.1 A case series of 48 patients, of whom 18 patients were not suitable for the procedure and 30 were successfully treated with a mitral annuloplasty device, reported a significant increase in Kansas City Cardiomyopathy Questionnaire score (assesses physical function, symptoms, social function and knowledge, and quality of life on a scale from 0–100; higher scores better) from 47 at baseline to 69 at 6‑month follow-up (p < 0.001). The 30 treated patients also had significantly improved function as measured using the New York Heart Association (NYHA) classification, from an average of 2.9 at baseline to 1.8 at 6-month follow-up (p < 0.001). Six-minute walk test results also improved, from an average of 307 m at baseline to 403 m at 6-month follow-up (p < 0.001).
2.3.2 The Specialist Advisers considered key efficacy outcomes to include mitral valve competence in the short (1 year), medium (5 years) and long term (10 years) for patients with degenerative disease, reduction in mitral regurgitation and mitral annular area, improved left ventricular function, improved NHYA classification, increase in 6-minute walk distance, increased quality of life scores and survival and reduced hospital admissions for patients with advanced heart failure.
2.4 Safety
2.4.1 Death was reported in 1 patient with multiple comorbidities 22 days after the procedure, in the case series of 48 patients. Progressive heart failure resulting in death 148 days after the procedure was reported in 1 patient who was not eligible for surgical treatment because of morbid obesity and other comorbidities, in a case series of 5 patients (the device was shown to be well-positioned on postmortem examination).
2.4.2 Myocardial infarction not requiring hospital admission was reported in 7% (3/46) of patients within 24 hours after the procedure in the case series of 48 patients.
2.4.3 Coronary sinus dissection in 1 patient (resolved without treatment) and coronary sinus perforation in 2 patients (1 treated conservatively and the other requiring pericardial drainage) were reported in the case series of 48 patients. A case series of 5 patients reported anterior interventricular vein perforation and pericardial effusion in 1 patient, and transient atrial fibrillation during cannulation of the coronary sinus in another.
2.4.4 Atrioventricular block was reported in 1 patient after device implantation in a case report. This was successfully treated with a cardiac resynchronisation device.
2.4.5 The Specialist Advisers listed an anecdotal adverse event of cardiac tamponade. They considered theoretical adverse events to include compression of the coronary artery, rupture, erosion or thrombosis of the coronary sinus or its tributaries, cardiac perforation, progressive stenosis and deformation of the mitral valve orifice or its chordal apparatus, inability to remove the device, and device migration, embolisation or fracture.
3 Further information
3.1 For related NICE guidance see www.nice.org.uk
Bruce Campbell
Chairman, Interventional Procedures Advisory Committee
March 2010
Personal data will not be posted on the NICE website. In accordance with the Data Protection Act names will be anonymised, other than in circumstances where explicit permission has been given.
It is the responsibility of consultees to accurately cite academic work in order that they can be validated.
This page was last updated: 19 August 2015