When blood vessels go wrong, why are we better at treating the heart than the head?

The strange discrepancies between how we treat strokes and heart attacks.

When I started practice in the early 1990s, medical attitudes to strokes and heart attacks couldn’t have contrasted more starkly.

Heart attacks were often dramatic and challenging; there were plenty of treatments to deploy, and much high-tech gadgetry to play with. Good outcomes were immensely satisfying, a confirmation that medicine made a difference. A stroke, on the other hand, felt like a depressing fait accompli. There was little to be done by way of treatment, survival was a matter of chance, and many patients were left with profound disabilities from which any recovery was painstaking and marginal.

The pathology underlying the two conditions is broadly similar. Every organ relies on uninterrupted perfusion of blood for its oxygen and nutrition. Clearly blood has to be liquid in order to circulate, yet it is also chock-full of tiny platelet cells, and a soluble chemical, fibrinogen, that will solidify into a clot at a moment’s notice. Blood vessels are lined with the biological equivalent of Teflon – the vascular endothelium – which ensures this clotting potential is held in check. Any breach in this endothelium activates the platelets, causing them to clump together in great numbers and to convert fibrinogen into its insoluble cousin, fibrin, which coagulates into a matted web.

This clotting cascade is vital in trauma, sealing damaged vessels and limiting blood loss; but when it is triggered in other circumstances, it can have catastrophic effects.

Cholesterol-rich plaques in arterial walls – the “furring up” of popular discourse – can swell and rupture the vascular endothelium. The ensuing clot may block the vessel entirely, causing death to the tissues downstream. If this occurs in a coronary artery, heart muscle dies – a myocardial infarction (MI), or heart attack. In the brain, the result is a stroke.

In the UK, deaths due to MI halved between 2002 and 2010. Some of this dramatic drop is because heart disease is becoming less common, thanks to the decline in smoking, and improvements in diet and exercise. The NHS has also become better at identifying and offering preventative medication to those at high risk. But around 50 per cent of the astounding increase in survival comes down to the transformation in treatment of those who have the misfortune to suffer a heart attack.

The management of MI has been revolutionised by techniques to unblock occluded coronary vessels, thereby salvaging as much of the blood-starved heart muscle as possible. The earliest attempts used “clot-buster” drugs known as thrombolytics, which cause the fibrin in the offending clot to dissolve. Thrombolytics still have an important place, but surgical approaches are ever more commonplace.

Angioplasty, where a wire is threaded up to the coronary vessels from an artery in the groin, has become the first-line emergency treatment for the most serious types of MI. A balloon at the end of the wire, or an implantable wire cage called a stent, can be deployed to reopen the blocked vessel.

Time is of the essence: the earlier that perfusion can be restored, the less heart muscle will die, and the better the outcome (in some cases, MI can actually be aborted). Ambulance services, and A&E and cardiology departments, have refined protocols for fast-tracking suspected MI sufferers, and “door-to-needle” or “door-to-balloon” times have been reduced substantially.

Stroke medicine has also undergone a revolution in recent years. Thanks to a sustained research effort led by the Stroke Association, much more is understood about maximising recovery following stroke, and most sufferers will now be treated in a dedicated stroke unit, which significantly improves outcomes.

The holy grail, though, would be comparable success in re-perfusing blood-starved tissue after stroke to what cardiologists are achieving in MI.

Stroke is different in a number of ways. Angioplasty is not useful in the majority due to the small size of the vessels within the brain. Thrombolysis should, in theory, be successful – but whereas re-perfusion can salvage heart muscle up to 12 hours after the onset of symptoms, brain tissue has a much narrower window of opportunity, probably around three to four hours.

And not all strokes are caused by clot. Around one in ten occur when a blood vessel ruptures and bleeds into the surrounding brain; you most certainly don’t want to give clot-busting drugs in those cases. They can be identified on a scan, but more challenging to predict are those patients suffering a clot-induced stroke who go on to bleed into the damaged neural tissue, something thrombolytics also make catastrophically worse.

The balance between benefit and harm is a fine one, and some experts have recently called for thrombolysis in stroke to be confined to clinical trials until the evidence to justify its use is clarified.

For now, at least, we continue to rescue the heart more successfully than the head.

Phil Whitaker is an award-winning novelist and a working doctor

Doctors treat a heart attack patient in Berlin, Germany. Image: Getty

This article first appeared in the 30 October 2013 issue of the New Statesman, Should you bother to vote?

Photo: Getty Images
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There are risks as well as opportunities ahead for George Osborne

The Chancellor is in a tight spot, but expect his political wiles to be on full display, says Spencer Thompson.

The most significant fiscal event of this parliament will take place in late November, when the Chancellor presents the spending review setting out his plans for funding government departments over the next four years. This week, across Whitehall and up and down the country, ministers, lobbyists, advocacy groups and town halls are busily finalising their pitches ahead of Friday’s deadline for submissions to the review

It is difficult to overstate the challenge faced by the Chancellor. Under his current spending forecast and planned protections for the NHS, schools, defence and international aid spending, other areas of government will need to be cut by 16.4 per cent in real terms between 2015/16 and 2019/20. Focusing on services spending outside of protected areas, the cumulative cut will reach 26.5 per cent. Despite this, the Chancellor nonetheless has significant room for manoeuvre.

Firstly, under plans unveiled at the budget, the government intends to expand capital investment significantly in both 2018-19 and 2019-20. Over the last parliament capital spending was cut by around a quarter, but between now and 2019-20 it will grow by almost 20 per cent. How this growth in spending should be distributed across departments and between investment projects should be at the heart of the spending review.

In a paper published on Monday, we highlighted three urgent priorities for any additional capital spending: re-balancing transport investment away from London and the greater South East towards the North of England, a £2bn per year boost in public spending on housebuilding, and £1bn of extra investment per year in energy efficiency improvements for fuel-poor households.

Secondly, despite the tough fiscal environment, the Chancellor has the scope to fund a range of areas of policy in dire need of extra resources. These include social care, where rising costs at a time of falling resources are set to generate a severe funding squeeze for local government, 16-19 education, where many 6th-form and FE colleges are at risk of great financial difficulty, and funding a guaranteed paid job for young people in long-term unemployment. Our paper suggests a range of options for how to put these and other areas of policy on a sustainable funding footing.

There is a political angle to this as well. The Conservatives are keen to be seen as a party representing all working people, as shown by the "blue-collar Conservatism" agenda. In addition, the spending review offers the Conservative party the opportunity to return to ‘Compassionate Conservatism’ as a going concern.  If they are truly serious about being seen in this light, this should be reflected in a social investment agenda pursued through the spending review that promotes employment and secures a future for public services outside the NHS and schools.

This will come at a cost, however. In our paper, we show how the Chancellor could fund our package of proposed policies without increasing the pain on other areas of government, while remaining consistent with the government’s fiscal rules that require him to reach a surplus on overall government borrowing by 2019-20. We do not agree that the Government needs to reach a surplus in that year. But given this target wont be scrapped ahead of the spending review, we suggest that he should target a slightly lower surplus in 2019/20 of £7bn, with the deficit the year before being £2bn higher. In addition, we propose several revenue-raising measures in line with recent government tax policy that together would unlock an additional £5bn of resource for government departments.

Make no mistake, this will be a tough settlement for government departments and for public services. But the Chancellor does have a range of options open as he plans the upcoming spending review. Expect his reputation as a highly political Chancellor to be on full display.

Spencer Thompson is economic analyst at IPPR