The benefits of mechanical thrombectomy 

Mechanical thrombectomy has several valuable attributes. First, it is by far the most advantageous intervention for selected patients with a large new acute ischaemic stroke. Second, mechanical thrombectomy is cost effective; saving bed days, complex medical rehabilitation and the expense of long-term social care facilities. Third, it can save lives or avert significant life-changing disability. Fourth, mechanical thrombectomy may be available for patients where contra-indications prevent use of thrombolysis. Finally it is a relatively quick intervention, typically taking a trained clinician less than one hour.

What is the research evidence for mechanical thrombectomy?

The clear advantage of mechanical thrombectomy over other available treatments, including thrombolysis alone, has been revealed with strong evidence from numerous randomised clinical trials. This evidence has been available from 2015. When treated within a 6 hourly time window, the number of patients that need to be treated to significantly decrease the dependency level measured on the commonly used scale of disability (modified Rankin scale) is estimated at between 3 to 5 patients. This is remarkable for an emergency intervention for a life-threatening or life-changing event. It is now believed that mechanical thrombectomy should be considered for selected patients up to 12 hours after the onset. This will significantly increase the numbers of patients suitable for this procedure.

How has this evidence been translated into planning and implementation in Scotland?

There was neither sufficiently effective planning nor timely implementation of this service in Scotland between 2014 and 2018. It is recognised that in the last 12 months detailed planning has now been taking place to provide this service in the future, initially in one hospital in Scotland.

What is the mechanical thrombectomy service in other European countries?

In contrast, European countries have been rapidly advancing mechanical thrombectomy services. A survey of European countries revealed rapidly increasing availability of stroke thrombectomies. In one year, 2016, Germany performed approximately 9000, France 4500, Spain, despite severe austerity measures within its health service, carried out 2400 1. Most European capital or major cities have a stroke mechanical thrombectomy service. Edinburgh and Scotland have none.

Initially slower to introduce mechanical thrombectomy than European healthcare services, England’s target for this year is 1000 with a plan and proposed funding for subsequent years to increase this to 8000 per year. Most NHS Trusts in England provide at least some access to stroke mechanical thrombectomy, even if transfer to another hospital is often required. Northern Ireland and the Republic of Ireland each have a centre actively offering this service.

What is the view of independent stroke national charities?

The two National Stroke Charities - The Stroke Association and Chest Heart & Stroke Scotland, have both voiced serious concern in 2019 about the lack of mechanical thrombectomy. The chief executive of Chest Heart and Stroke Scotland said: “Right now people with stroke across Scotland are missing out on their best chance of recovery simply because they live north of the border. That is the worst kind of situation for both doctors and their patients” 2.  

The chief executive of the Stroke Association, emphasising the benefits said: “Thrombectomy is the game changer” 3.

What is the view of other specialists in England?

A leading specialist who performs mechanical thrombectomy in England said: “We see many of our patients walking out of hospital after this procedure but that is not the case across the country, and that is a scandal. It is very frustrating when I hear of patients at other NHS centres, many of them young with the rest of their lives ahead of them, severely disabled by a stroke which could be treated with this procedure” 3.

A recent attempt to transfer a young new acute stroke patient from Edinburgh to England for mechanical thrombectomy in weekday business hours, was unsuccessful due to lack of co-ordinated air ambulance support.

What is the view of patients who have received this treatment?

One patient recently treated with mechanical thrombectomy said: “I’m able to look after myself now, get myself up and down the stairs, do the housework and take my dog for a walk. I now realise how fortunate I have been to live close to a hospital that performs this procedure.” 3.

Another patient treated with thrombectomy said: ”I remember the fear I felt whist waiting to find out if I was going to receive the procedure. I feel like I was one of the lucky ones” 2.

What is the future for thrombectomy in Scotland?

NHS Scotland National Planning board has recently estimated planning for a budget of 800 patients per year. NHS Scotland would need to gradually build up the numbers treated towards this target. 

A report by Chest Heart and Stoke Scotland, estimates that initially about 600 patients per year would be suitable for mechanical thrombectomy, estimating 300 would have significantly less disability and in 120 this would prevent dependence on others for daily care. There is also an economic benefit – called invest-to-save. For every pound spent on mechanical thrombectomy, it is estimated that about half is recouped in savings: complex medical care, stroke rehabilitation, unemployment, and subsequent social care including care homes.

In terms of solutions for Scotland, mechanical thrombectomy involves specialists skilled in neurovascular intervention in a specialised intervention suite, supported by trained radiographers, nurses and anaesthetists performing a procedure only a few hours after onset of the patient’s symptoms. A highly coordinated multi-specialist approach is required to select and transport the patient in time. This also requires support after the procedure for a safe environment and to maximise neurological recovery.  Delivering mechanical thrombectomy demands collaboration across specialities and hospitals and a 24/7 service is likely to require some innovative thinking for recruitment and training in the interventional procedure, working across traditional boundaries. Initially only radiologists performed mechanical thrombectomy. In Europe physicians from other backgrounds train in mechanical thrombectomy, in order to maintain a hybrid workforce for 24/7 rotas. Training in this technique of physicians from various backgrounds, is starting in England.

Previously, Scotland was proud to be at the forefront of the last significant advance in the late 1990’s, for a new emergency treatment for people having an ischaemic Stroke – thrombolysis. In the early 2000’s pioneering thrombectomies were performed in Edinburgh. Thrombectomy is now widely available elsewhere today, not only in Europe, but also Scandinavia, Australia and North America; most modern healthcare systems. Currently there is no service in Scotland. There remains no date set for starting this service. This inequality of provision between Scotland and other countries worldwide and even the other devolved nations across Britain, is clear. It is time this is addressed.




1.The Lancet Vol. 392, No. 10154, 2018.

2.Times, 14th January 2019.

3.The Guardian 2nd February 2019.

Paul Gillen

Contact: Paul Gillen 0131 247 3658