Interventional procedure consultation document

Percutaneous laser coronary angioplasty

Treating blocked coronary arteries by using a laser with a minimally invasive technique

Blood vessels from the heart can become blocked by the build-up of deposits of fat on their inner surface. This can cause problems with the heart and circulation such as angina.

In this technique, a flexible plastic tube (a catheter), connected to a laser, is inserted though the leg and into the circulation. It is moved to the site of the blockage and the laser is then used to burn away the deposits. This procedure may be done on its own or with other techniques to help remove the deposits and/or keep the blood vessel open.

The National Institute for Health and Clinical Excellence (NICE) is examining percutaneous laser coronary angioplasty 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 laser coronary angioplasty.

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• The Advisory Committee will then prepare draft guidance which will be the basis for NICE’s guidance on the use of the procedure in the NHS in England, Wales, Scotland and Northern Ireland.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: 28 September

Target date for publication of guidance: January 2010

1 Provisional recommendations

1.1 Current evidence on the safety and efficacy of percutaneous laser coronary angioplasty is adequate to support the use of this procedure in carefully selected patients for whom conventional angioplasty would otherwise be technically difficult, provided that normal arrangements are in place for clinical governance, consent and audit.

2 The procedure

2.1 Indications and current treatments

2.1.1 Coronary artery disease (CAD) refers to the narrowing and occlusion of the coronary arteries as a result of atherosclerosis. This can cause angina, myocardial infarction and heart failure.

2.1.2 Treatment options for patients with CAD with severe stenosis or occlusion include thrombolysis, percutaneous balloon angioplasty, stent placement, percutaneous cutting balloon or coronary artery bypass grafting.

2.1.3 Percutaneous laser coronary angioplasty has been used for CAD with severe stenosis or atherosclerotic occlusion, when standard techniques for recannalisation are unlikely to succeed or have failed.

2.2 Outline of the procedure

2.2.1 Percutaneous laser coronary angioplasty aims to penetrate plaque within coronary arteries that is not amenable to standard techniques such as balloon angioplasty or stenting alone.

2.2.2 A thin, flexible fibre-optic catheter connected to a laser-generating source outside the body is introduced via the femoral artery. The catheter is advanced over a guidewire through the artery to the blockage in the coronary artery, under fluoroscopic guidance. The tip of the catheter system emits pulses of laser light to vaporise the plaque while being slowly advanced across the lesion.

2.2.3 Percutaneous laser coronary angioplasty has also been done using a laser guidewire system but that method is not now in regular use.

2.2.4 This procedure is often used with adjunctive balloon angioplasty and followed by angiography to document the results.

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/IP830overview

2.3 Efficacy

2.3.1 A randomised controlled trial (RCT) of 303 patients treated with laser guidewire or mechanical guidewire reported procedural success (defined as the ability to cross the target lesion at the first attempt) in 53% (76/144) and 47% (75/159) of patients respectively (p = 0.33). A non-randomised controlled study of 3733 procedures reported that ‘lesion success’ assessed angiographically was achieved in 89% and 94% of native vessels treated with laser angioplasty using 2 different laser devices, and in 91% and 95% of saphenous vein grafts for which laser treatment was attempted (absolute figures not stated). A case series of 958 patients reported that among 55 patients who underwent immediate postoperative angiographic assessment, coronary stenosis (assessed by the percentage of artery diameter blocked) decreased from 83% at baseline to 49% following laser angioplasty and to 38% following adjunctive balloon angioplasty (absolute figures not stated).

2.3.2 The RCT of 303 patients treated with laser guidewire or mechanical guidewire reported no major adverse cardiac events in 54% (78/144) and 67% (106/159) of patients respectively at 400-day follow-up (p = 0.026).

2.3.3 Major adverse cardiac events (death, myocardial infarction or revascularisation) were more frequent after laser angioplasty compared with balloon angioplasty in the meta-analysis of 9222 patients at up to 1-year follow-up (odds ratio [OR] 1.32; 95% CI 1.01 to 1.73).

2.3.4 A case series of 1862 patients reported that 71% of patients had an improvement in their angina symptoms, 13% had unchanged symptoms and 16% had worse symptoms at 6-month median follow-up (absolute figures not stated).

2.3.5 A meta-analysis of 16 studies including a total of 9222 patients reported that angiographically measured restenosis occurred more frequently after laser angioplasty than after balloon angioplasty (OR 1.55; 95% confidence interval [CI] 1.09 to 2.20) at follow-up of between 3 months and 1 year. An RCT of 96 patients treated by laser angioplasty and adjunctive balloon angioplasty or by balloon angioplasty alone reported restenosis in 52% and 47% of patients respectively at 163 days median follow-up (p = not significant; absolute figures not stated).

2.3.6 The case series of 1862 patients reported restenosis greater than 50% of the artery diameter in 54% (434/797) of eligible patients undergoing angiographic assessment at 6-month median follow-up. A case series of 495 stenosed saphenous vein grafts treated by laser angioplasty reported restenosis in 55% of the 161 patients who had angiographic assessment at 6-month follow-up (absolute figures not stated).

2.3.7 The Specialist Advisers listed key efficacy outcomes as procedural success, angiographic success, quality-of-life scores and target vessel revascularisation and cardiac enzyme level post procedure.

2.4 Safety

2.4.1 The meta-analysis of 9222 patients treated by laser angioplasty or balloon angioplasty reported no difference between the groups in the rate of myocardial infarction at 30-day follow-up (OR 1.39; 95% CI 0.69 to 2.82). A meta-analysis of 3012 patients being treated for in-stent restenosis reported that the pooled mean rate of major adverse cardiac events was 35% following laser angioplasty, 29% for balloon angioplasty and 31% for stent-in-stent treatment (absolute figures not stated).

2.4.2 A non-randomised controlled study of 8932 procedures reported that the rate of arterial perforation was 2% (5/242) for laser angioplasty less than 1% (11/7905) for balloon angioplasty and 0% (0/116) for mechanical rotational atherectomy.

2.4.3 The Specialist Advisers listed theoretical adverse events as death, coronary dissection, abrupt vessel closure, thermal damage to the vessel and restenosis.

3 Further information

3.1 For related NICE guidance see www.nice.org.uk

Bruce Campbell

Chairman, Interventional Procedures Advisory Committee

September 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.}