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
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George Osborne's mistakes are coming back to haunt him

George Osborne's next budget may be a zombie one, warns Chris Leslie.

Spending Reviews are supposed to set a strategic, stable course for at least a three year period. But just three months since the Chancellor claimed he no longer needed to cut as far or as fast this Parliament, his over-optimistic reliance on bullish forecasts looks misplaced.

There is a real risk that the Budget on March 16 will be a ‘zombie’ Budget, with the spectre of cuts everyone thought had been avoided rearing their ugly head again, unwelcome for both the public and for the Chancellor’s own ambitions.

In November George Osborne relied heavily on a surprise £27billion windfall from statistical reclassifications and forecasting optimism to bury expected police cuts and politically disastrous cuts to tax credits. We were assured these issues had been laid to rest.

But the Chancellor’s swagger may have been premature. Those higher income tax receipts he was banking on? It turns out wage growth may not be so buoyant, according to last week’s Bank of England Inflation Report. The Institute for Fiscal Studies suggest the outlook for earnings growth will be revised down taking £5billion from revenues.

Improved capital gains tax receipts? Falling equity markets and sluggish housing sales may depress CGT and stamp duties. And the oil price shock could hit revenues from North Sea production.

Back in November, the OBR revised up revenues by an astonishing £50billion+ over this Parliament. This now looks a little over-optimistic.

But never let it be said that George Osborne misses an opportunity to scramble out of political danger. He immediately cashed in those higher projected receipts, but in doing so he’s landed himself with very little wriggle room for the forthcoming Budget.

Borrowing is just not falling as fast as forecast. The £78billion deficit should have been cut by £20billion by now but it’s down by just £11billion. So what? Well this is a Chancellor who has given a cast iron guarantee to deliver a surplus by 2019-20. So he cannot afford to turn a blind eye.

All this points towards a Chancellor forced to revisit cuts he thought he wouldn’t need to make. A zombie Budget where unpopular reductions to public services are still very much alive, even though they were supposed to be history. More aggressive cuts, stealthy tax rises, pension changes designed to benefit the Treasury more than the public – all of these are on the cards. 

Is this the Chancellor’s misfortune or was he chancing his luck? As the IFS pointed out at the time, there was only really a 50/50 chance these revenue windfalls were built on solid ground. With growth and productivity still lagging, gloomier market expectations, exports sluggish and both construction and manufacturing barely contributing to additional expansion, it looks as though the Chancellor was just too optimistic, or perhaps too desperate for a short-term political solution. It wouldn’t be the first time that George Osborne has prioritised his own political interests.

There’s no short cut here. Productivity-enhancing public services and infrastructure could and should have been front and centre in that Spending Review. Rebalancing the economy should also have been a feature of new policy in that Autumn Statement, but instead the Chancellor banked on forecast revisions and growth too reliant on the service sector alone. Infrastructure decisions are delayed for short-term politicking. Uncertainty about our EU membership holds back business investment. And while we ought to have a consensus about eradicating the deficit, the excessive rigidity of the Chancellor’s fiscal charter bears down on much-needed capital investment.

So for those who thought that extreme cuts to services, a harsh approach to in-work benefits or punitive tax rises might be a thing of the past, beware the Chancellor whose hubris may force him to revive them after all. 

Chris Leslie is chair of Labour's backbench Treasury committee.