Endoaortic balloon occlusion for cardiac surgery (interventional procedures consultation)

NATIONAL INSTITUTE FOR HEALTH AND CLINICAL EXCELLENCE

Interventional Procedure Consultation Document

Endoaortic balloon occlusion for cardiac surgery

During major heart surgery, the flow of blood through the heart needs to be stopped temporarily. In endoaortic balloon occlusion, a flexible tube (catheter) with a balloon attached to its tip is inserted into an artery in the groin (femoral artery) and threaded up to the heart. When the catheter is in the correct position in the heart, the balloon is filled with saline. As the balloon expands it blocks the aorta, which is the largest artery in the body. With the aorta blocked, the heart surgery can be performed. After heart surgery, the balloon and catheter are removed and the blood flow is restored.

The National Institute for Health and Clinical Excellence is examining endoaortic balloon occlusion for cardiac surgery and will publish guidance on its safety and efficacy to the NHS in England, Wales, Scotland and Northern Ireland. The Institute'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 endoaortic balloon occlusion for cardiac surgery.

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 preliminary recommendations
the identification of factual inaccuracies
additional relevant evidence.

Note that this document is not the Institute's formal guidance on this procedure. The recommendations are provisional and may change after consultation.

The process that the Institute 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The Advisory Committee will then prepare draft guidance which will be the basis for the Institute's guidance on the use of the procedure in the NHS in England, Wales, Scotland and Northern Ireland.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 Institute's 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 how it might be improved.

Closing date for comments: 30 January 2008
Target date for publication of guidance: April 2008

Note that this document is not the Institute's guidance on this procedure. The recommendations are provisional and may change after consultation.

1	Provisional recommendations
1.1	Current evidence on the safety and efficacy of endoaortic balloon occlusion for cardiac surgery is adequate to support the use of this procedure provided that normal arrangements are in place for consent, audit and clinical governance.
1.2	The procedure should only be carried out by a highly experienced team and with the use of transoesophageal echocardiography.

The procedure

2.1

Indications and current treatments

2.1.1

Endoaortic balloon clamping is performed to achieve temporary obstruction of the aorta during cardiac surgery, including mitral valve repair or replacement, and coronary artery bypass grafting (CABG).

2.1.2

Occlusion of the aorta is required in a number of cardiac operations. This is normally achieved by external application of an aortic cross-clamp, either during conventional 'open' surgery, or during minimally invasive cardiac procedures.

2.2

Outline of the procedure

2.2.1

This procedure is usually employed during minimally invasive cardiac operations (known as port-access surgery) that require endovascular aortic occlusion, cardioplegia and left ventricular decompression.

2.2.2

A balloon catheter is inserted through the skin into an artery (normally the femoral artery in the groin) and manipulated towards the aortic root. The balloon at the tip of the catheter is filled with saline to occlude the aorta and prevent blood flow. Various devices can be used for this procedure.

2.2.3

Continuous echocardiographic monitoring is necessary to detect balloon migration.

Sections 2.3 and 2.4 describe efficacy and safety outcomes which were available in the published literature and which the Committee considered as part of the evidence about this procedure. For more details, refer to the sources of evidence (see appendix).

2.3

Efficacy

2.3.1

There were no outcomes reported in the literature that related directly to the efficacy of endoaortic balloon occlusion alone.

2.3.2

The Specialist Advisers considered key efficacy outcomes to include efficiency of cardioprotection, reduced length of hospital stay, reduced duration of cardiac arrest and avoidance of the use of a cross-clamp from outside, thus potentially reducing stroke risk in patients with very calcified aorta.

2.4

Safety

2.4.1

In a case series of 306 patients treated with endoaortic balloon occlusion, the 30-day mortality rate was 1% (3/306) and the rate of late deaths (mean follow-up 20 months) was 2% (6/306). A case series comparing 117 patients treated with endoaortic balloon occlusion with 117 matched controls treated with conventional aortic cross-clamping reported one perioperative death in each group. In four case series, 5% (11/209), 4% (6/151), 1% (1/127), and 25% (13/52) of patients who were treated with endoaortic balloon occlusion died in hospital.

2.4.2

The three case series of 306, 209, and 117 patients treated with endoaortic balloon occlusion reported aortic dissection in 1% (3/306), 1% (3/209), and 1% (1/117) of patients, respectively. One aortic dissection in the case series of 151 patients was judged by the authors to be unrelated to the endoaortic balloon occlusion device. In the case series that described 58, 120 and 127 patients, no aortic dissections occurred.

2.4.3

In the case series of 449 patients, there were no significant differences in the incidences of arrhythmias, pulmonary dysfunction, bleeding, renal failure or low cardiac output between those treated with endoaortic balloon occlusion and those treated with transthoracic clamping. However, the rates of neurological complications were higher in patients who had endoaortic balloon occlusion (p < 0.05). (Neurological complications were defined as stroke and transient hemiplegia; however, absolute numbers were not given).

2.4.4

In five case series, stroke or transient ischaemic attack was reported in 4% (2/52), 2% (2/127), 0.4% (1/306), 1% (1/117) and 1% (1/151) of patients.

2.4.5

In six case series, re-exploration for bleeding or tamponade was required in 10% (6/60), 9% (26/306), 7% (14/209), 6% (9/151), 4% (5/117), 4% (1/23) and 2% (3/127) of patients treated with endoaortic balloon occlusion.

2.4.6

In the case series of 306 and 151 patients, myocardial infarction was reported in 1 and 2 patients, respectively.

2.4.7

The Specialist Advisers reported anecdotal adverse events including aortic dissection, balloon puncture, balloon migration, damage to aortic intima, device movement causing loss of occlusion, femoral artery damage, difficulty positioning the balloon, death due to failure to deliver cardioplegia, and inability to complete planned surgery due to occlusion failure. Additional theoretical adverse events noted by the advisers were stroke, inadequate myocardial protection or cerebral ischaemia due to balloon misplacement and arterial embolism.

2.5	Other comments
2.5.1	The Committee noted that there have been technical modifications and evolution in the design of the endoaortic balloons, with the intention of improving their performance; and that newer designs may be associated with lower complication rates.

Bruce Campbell
Chairman, Interventional Procedures Advisory Committee
January 2008

Appendix:

Sources of evidence

The following document, which summarises the evidence, was considered by the Interventional Procedures Advisory Committee when making its provisional recommendations.

'Interventional procedure overview of endoaortic balloon occlusion for cardiac surgery', January 2008

Available from: http://www.nice.org.uk/guidance/index.jsp?action=download&o=38781.

This page was last updated: 30 March 2010