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BRITISH BROADCASTING CORPORATION
RADIO SCIENCE UNIT
CASE NOTES Programme no. 4 - Aneurysms
RADIO 4
TX DATE: TUESDAY 19TH AUGUST 2008 2100-2130
PRESENTER: MARK PORTER
CONTRIBUTORS: TRICIA BURKE
JOHN WOLFE
HANY HAFEZ
ANDY CLIFTON
PRODUCER: ERIKA WRIGHT
NOT CHECKED AS BROADCAST
PORTER
Blood circulates around the human body under surprisingly high pressure - enough to produce a two metre high fountain if an artery leaks. And that is exactly what can happen with aneurysms - swellings caused by a weakening in the arterial wall which, if left, can eventually burst leading to life threatening bleeding.
Aneurysms can occur in almost any artery in the body, but the bigger the vessel, the heavier the blood loss and they don't come any bigger than the aorta - the hosepipe sized artery leading away from the heart. The aorta arches down through the chest before running into the abdomen where it divides in two to form the arteries that supply the legs. And it's just above this division in the abdominal section that most aortic aneurysms occur.
Tricia Burke is vascular nurse specialist at St Mary's Hospital in London
BURKE
If you imagine the aorta is like a balloon but it's a balloon with another balloon inside it, so it's blowing off but there's a layer in between, so the inside layer will first burst but it's still held together by the outside. So that's what we would call a leak, so the blood is spurting out but the aorta hasn't fully burst yet, so it may be contained and that's the one where we have a little time window, so when that first goes if you get to us very quickly or you're already in hospital that's the one that we have the opportunity to fix. If the outside is gone as well, both layers, that's the one that's really not one that can be survived.
PORTER
I mean you can be dead within a couple of minutes, it's literally like having a hosepipe turned on in your belly.
BURKE
Not even a couple of minutes, it can be a minute, 30 seconds, if it bursts. It's blood that's supposed to be circulating in your body, coming from the heart, that's now just hosing out into your tummy, instead of all of your blood vessels.
WOLFE
It tends to occur in older people and mostly in men and that's the standard more common form of aneurysm.
PORTER
John Wolfe is one of the consultant vascular surgeons at St Mary's.
WOLFE
It's related to degeneration of the wall which is related to diet, it's related to smoking and some of those things but also there is a familial tendency. And there's an unlucky group which can affect both sexes equally who can be much younger and that is a disease of the aortic wall that is nothing to do with the degeneration that can happen as you get older.
PORTER
So these can be, in inverted commas, "quite clean living people" but still have a problem with an aneurysm?
WOLFE
Yes, yes.
PORTER
Looking at your typical clinic that you would run how do people get to know that they've got an aneurysm, how do they find out?
WOLFE
The most frequent reason nowadays is that they're having some form of test for something else and it's picked up incidentally during that test and that's the reason that we pick up more of the aneurysms nowadays. Some people will present with backache, but that's not very many, and some people will actually find that they've got a pulsating lump in their tummy, some people say - go to their doctor and say their heart's slipped because they can feel this pulsating mass in the abdomen - tummy.
PORTER
And presumably when the aneurysm's fairly extreme?
WOLFE
Yes.
PORTER
So most people will have been picked up by accident, is what you're saying effectively.
WOLFE
Yes.
PORTER
Which is why the Department of Health has introduced a new screening programme that uses ultrasound scans to pick up aneurysms early enough to do something about them before they rupture. A move that could save 1500 lives a year.
Vascular surgeon Hany Hafez is Director of the screening programme at St Richard's Hospital in Chichester.
HAFEZ
Mark is now laying - lying on a couch and pulled his shirt up. I'm going to put some gel just above his belly button.
PORTER
It's essentially the same technology you use for looking at a baby.
HAFEZ
Oh absolutely, it's exactly the same technology as you use in examining pregnant ladies. What I can see now on the screen is the aorta and if you look carefully it's actually pulsating.
PORTER
Yeah, so that's the aorta.
HAFEZ
That's the aorta and what we do is we can measure the size ...
PORTER
And a normal aorta would be what sort of size?
HAFEZ
A normal aorta in a man would be about 1.8 to 2 centimetres in diameter. And your aorta is 1.6 centimetres in diameter.
PORTER
Good.
HAFEZ
So it's perfectly normal. And it should remain so for many, many more years. Because once we have a normal aorta that chances of this aorta becoming or having an aneurysm in the future are very, very small.
PORTER
And in terms of measurement at what stage would you have started to say ooh this is looking a bit larger than normal, where's your cut off?
HAFEZ
At 3 centimetres at the moment, that's what we start to consider as an aorta that would need to be followed up.
PORTER
So the protocol in the UK is currently what?
HAFEZ
To screen men at the age of 65 because from work that's been done before we know that this is the best age to pick up these aneurysms. If you screen at the age of 75, for example, we found that the instance of aneurysms have almost tripled but you would be missing out on a number of aneurysms that have already caused problems before this age and that's what we want to avoid. So the safest age to start with is 65 where the majority of aneurysms would be still small and then you can follow them up. And the frequency of future scans depend on the size. So if the size of the aneurysm is between three and four and half centimetres then they need a scan every year, if it's above four and a half centimetres and less than five and a half centimetres they need a scan every three months because the growth of an aneurysm accelerates as the aneurysm gets bigger.
PORTER
Many patients have already benefited from the pilot screening programme at Chichester. Tony Hoskins is one of them
HOSKINS
It turned out that I had got a moderate aneurysm and was told to come back at yearly intervals so that they could keep an eye on it. About a year later he decided that it had enlarged sufficiently to have surgical treatment. And I was fitted up to go into hospital in November to have the operation. Having made such a remarkable recovery I find myself now, only a few months after the aneurysm operation, going for reasonably lengthy walks on the Downs. I think it is a wonderful idea and I only hope that as many people as possible will be restored to health as I have been.
HAFEZ
Not all aneurysms will grow big enough to warrant treatment.
PORTER
So if you come in and have a normal scan at 65 do you need to come back again?
HAFEZ
You don't need to come back again.
PORTER
What about women?
HAFEZ
Women do develop aneurysms but they're much less likely than men, the risk in a man is about six times more than it is in a woman to develop an aneurysm. They also develop aneurysms at the later age, about even 10 years difference in age for women and men, but certainly this is something that we will have to revisit in the future.
PORTER
This is an evidence based decision. My practice in Gloucester was one of the early ones for - looking at the pilot for this. What is the evidence that this intervention is useful? First of all, give me some idea of the proportion of men at 65 who might have a problem?
HAFEZ
It's about 3% of men aged 65 will turn out to have an aneurysm.
PORTER
And if we'd leave those three men, in other words we didn't scan them, we didn't know they had a problem, what would be the likely outcome?
HAFEZ
The likely outcome varies because we don't know how yet how to tell the difference between an aneurysm that will grow to require treatment and an aneurysm that will grow very, very slowly and will not. So we have no choice but to follow all of these aneurysms up. The chances of a person with an aneurysm at the age of 65 having an operation is probably about 30-50% in due course, usually over a period of about five - 10 years, it depends on the size of the aneurysm at the initial scan.
PORTER
So roughly half will need surgery ...
HAFEZ
Roughly, very roughly.
PORTER
.. presumably that's because those same half, if left, would rupture?
HAFEZ
Precisely yes.
PORTER
Until screening is more widely available - and it's likely to take at least five years to roll it out over England alone - most people with aneurysms will be blissfully unaware of the potential time bomb ticking away in their tummy. Some will be picked up incidentally during investigations for other problems, but for many the first sign of trouble is when they rupture. And that's often too late. Surgeon John Wolfe again.
WOLFE
The situation is extremely serious and unlike elective aneurysms we've not made a great deal of progress in doing better. With elective aneurysms our ability to get patients through the operation and reduce the risks has got dramatically better over the last decade or so.
PORTER
Is there a certain size that the aneurysm has to get to or ...?
WOLFE
Yes and I mean fortunately we're very lucky, we've got some very large studies with very, very good data on this now. And I think we can with some confidence leave aneurysms until they're five and a half centimetres with the knowledge that below that level they really aren't dangerous. And at about five and a half centimetres then we do need to consider surgery and in the majority of patients we'd operate but that also depends on the general problems that the patient has other than the aneurysm of course. For ruptured aneurysms a lot of the patients don't even get to hospital because obviously it's a major blood vessel and as soon as the blood starts pouring out of that they can die very quickly. If they get to hospital then the operation still carries approximately a 50% mortality rate and that is more to do with the state of the patient when you start the procedure than it is to do with the procedure itself. The procedure itself is very similar to the one we do electively, except we have to do it quite quickly. But the problem is that you're starting off with a patient who may already have had a cardiac arrest, they may not have any urine coming from their kidneys - they're very, very sick before you start the procedure.
PORTER
Because of a catastrophic blood loss.
WOLFE
Catastrophic blood loss - yes.
PORTER
And to put that into perspective: they might lose - how much blood can they lose internally?
WOLFE
Well they can lose their whole circulating volume, in which case then they won't survive or a bit less in which case we might be able to do something about it.
BURKE
Definitely people who are come in with a planned scenario do better - they're psychologically prepared for it and we've had the opportunity to optimise them beforehand, so we've checked your heart, checked your kidneys, checked your lungs and done everything we can possibly to make sure you're fit and healthy to undergo the procedure. If in an emergency scenario we don't have that opportunity to optimise your health so you will go to the intensive care, you'll be kept asleep, your kidneys if they had disease that we didn't know about might take longer to recover, similarly your lungs particularly in smokers, we would always encourage people to stop smoking before an operation, so people coming in an emergency scenario they tend to take longer to get through the intensive process and then also the longer process afterwards.
PORTER
And of course they've had - they might have had a period of sustained low blood pressure before they came in, when they were unconscious as an emergency, and that can have knock on effects on other parts of the body.
BURKE
Absolutely. The kidneys, the brain, the legs, lots of different problems and you know obviously they're more at risk of complications.
PORTER
Could you give me some idea of how the emergencies present, what they actually look like when they get here, presumably they're pretty poorly?
BURKE
Yeah very much so. So if - sometimes they're awake, sometimes they're not depending on how long it's taken them to get to us, usually a typical presentation will be a collapse, either with some sudden back pain, which is quite a sudden presentation, you'll feel it for a couple of minutes but if the aneurysm has burst it's very quick until you collapse. They'll be brought to us usually unconscious, very low blood pressure and it's a very, very dangerous time, I mean time is really of the essence in that scenario. So very, very quickly into the accident and emergency unit and if we know it's an aneurysm we'll take them straight to the operating theatre.
PORTER
Presumably if the patient's unconscious they can't tell you what's happened to them, so you're going purely by the clinical signs that you're seeing, you have a high index of suspicion?
BURKE
Definitely. I mean we do have certain tools, I mean there are like fast scanners in the accident and emergency unit where we can do quick ultrasounds - if there's blood in the belly it's a good indicator. Usually they'll need to be opened anyway in that sort of a scenario so...
PORTER
To find out what's going on.
BURKE
... we find what's in there. If they're stable enough, if their blood pressure is holding and we have say 10 minutes to play with that we can take them to the CT scanner and get much more detailed information it allows us a better opportunity as to what we may do.
PORTER
Of course this is major surgery and some patients won't go home at all, what are the differences in survival rates?
BURKE
It depends on how long it takes to get to us. If an aneurysm bursts when you're outside of the hospital environment statistically there's about an 80% mortality in that scenario, so about 80% of people do not survive a rupture whatsoever, that's whether they get to hospital or not. If you rupture in a hospital your rate is anywhere between 40-70%, even within a hospital. Here in our hospital our mortality rate for ruptures is less than 10%. So if you get to us in time you've got a good chance but it's the getting to us, it's - you know somebody finding you collapsed, if you're at home by yourself and your aneurysm bursts unfortunately it's unlikely you would get to us in time.
PORTER
There are two approaches to dealing with an aneurysm. The conventional open operation through a large incision in the abdomen, or the newer keyhole technique where surgeons go in through the groin. John Wolfe.
WOLFE
Well if we use the open technique, which is a well tried technique that's been used for 45-50 years, then we take a piece of Dacron, which is a form of nylon, and it's in the form of a tube and we sew that in to the area of the aorta that has degenerated and become an aneurysm and that's just sewn in with a piece of Prolene, which is like strong fishing line, on a standard stitching technique and that's conceptually a very straightforward thing to do. The problem with it is that you have to block the aorta in order to do it and therefore you put pressure on the heart and of course you have the added problem that you've had to do a large cut in the abdominal wall, in the tummy, in order to do the procedure in the first place.
PORTER
How long does it take for you to perform that operation in theatre?
WOLFE
About two hours.
PORTER
And that involves opening the patient with a vertical incision ...
WOLFE
Yes.
PORTER
... and then going right down to - because the aorta sits at the back in front of the spine.
WOLFE
So the patient takes quite a long time to recover. If you use the endovascular technique, that's what you would probably call the keyhole technique, then the procedure can be done through the groin and using a fairly fat plastic cannula you can insert the graft in through the groin. And again it's a form of nylon - Dacron - but it's thinner and therefore it can be squished into this cannula and passed up through the groin. And in order for it to come open in the correct place it's got metal struts in place within that Dacron that spring open, rather like an umbrella, once it's inside and in the correct position to be deployed.
PORTER
And we've got one here, I mean it's an inch and a bit - you'd never imagine you'd be able to get that into the groin but of course it all scrunches up. It reminds me of one of those tents that you can pull out of the bag and it instantly erects itself.
WOLFE
That's a very good analogy actually, that's a very good analogy.
PORTER
And that just remains fixed inside, so actually the aneurysm's still there, you're just laying this on the inside to take the pressure off it?
WOLFE
Yes and I mean if you think about it providing you've got a solid area of aortic wall, like a good area of hosepipe, then the fact that it's degenerated in between and been replaced by a piece of piping is all you require because you're taking the pressure off that area that is ballooning up and if you're taking pressure off the balloon then it won't burst.
PORTER
You are unlucky if you need to have one aortic aneurysm repaired, but this patient on the ward along the corridor at St Mary's was recovering from his second. Both aneurysms were picked up in time - albeit accidentally.
AGNELLI
The first time it was open surgery. I went to the hospital, it was something else, and they discover that I had an aneurysm. And he said to me quickly get up and go and see your doctor.
PORTER
So - and then 24 hours later you were having major surgery.
AGNELLI
Yes. I recover very quickly okay, very quickly and I think it was - I know it was more hurtful and everything but I recover successful.
PORTER
That was an open one, so you had a big sort of 10-12 inch scar down the front of your tummy.
AGNELLI
Yes.
PORTER
But had you ever heard of aneurysms before?
AGNELLI
Never, never.
PORTER
And they presumably replaced the damaged bit with a bit of pipe work and that was how long ago?
AGNELLI
Ten years exactly, exactly on the day when I come back again for this one.
PORTER
So what happened that meant that you needed more surgery?
AGNELLI
For this one? The same thing again - I went for a different story and they took us back and the doctor said us down and she said to us I'm sorry I have to tell you Mr Agnelli that your aneurysm is back.
WOLFE
It's not many years ago that the only procedure was an open procedure and it wasn't until the mid-'90s that really people started doing endovascular repairs of aneurysms and the technology involved with that is evolving very rapidly. So at the moment I think I would say that the jury is still out on whether it's safer and better to do an endovascular repair in somebody who's a bit younger, in an older person then there are clear advantages in the short term if you do an endovascular repair because of the risks of quite a major open operation. But in a younger person, at the moment, that seems to be counterbalanced by some of the longer term problems with the endovascular repair, simply because it's a newer technique. And as the technology changes so we're able to overcome some of the difficulties but nevertheless there are still areas where improvements need to be made with the endovascular technique and therefore in a younger patient some of us would be less confident about suggesting an endovascular graft because of the uncertainty in the long term future.
PORTER
And in good vascular units like the one at St Mary's, planned repairs have now become fairly routine, with at least a 95% success rate . But it's still a big operation to recover from. Vascular nurse specialist Tricia Burke.
BURKE
If you have the traditional sort of open repair probably about a week, maybe 10 days, just depending on the age and the general fitness of the patient. And then with the more - the less invasive surgery, like the stent grafts, usually it can be anywhere between four to six days, but again depending on the fitness of the patient.
PORTER
And the emergency's that little bit longer in each case?
BURKE
Yeah and that very much depends on how long they take to get off the intensive care unit. Once they're off intensive care you can kind of gauge but it's that hit that they take in the emergency scenario.
PORTER
What about once the patient gets home, everything's gone according to plan, what sort of follow up do these patients need?
BURKE
Again that will depend on the type of operation you have. We'll see everybody in the outpatient clinic because people who have aneurysms have cardiovascular disease, so we'll always be checking for other things and for new aneurysms. But if - we will always scan your aorta, so if you've had the old fashioned operation we'll scan it every couple of years just to check for new ones. But with stent grafts you have regular CT scans because again we haven't taken away the damaged part of the aorta, we've just reinforced it from the inside, so we need to always check that that stays how it should be and that there's no leaks or anything. So in those patients they will come every six months initially for a CT scan and then every year.
PORTER
But once the patient has made it home the outlook is pretty good, most of the dangers is around the operation?
BURKE
It's the biggest danger - danger period for them yes. So generally those that go home do very, very well.
PORTER
Aortic aneurysms may be the biggest type you can get but much smaller aneurysms, just a few millimetres across, can be just as lethal if they rupture in a confined space like the skull.
At least a million people in Britain are walking around with an intracranial aneurysm. The majority occur in women, who will never know they have a problem as long as the aneurysm remains intact - as most do. But the outlook is very different if it bursts. Andy Clifton is a consultant neuroradiologist at St George's Hospital in London, where he treats intracranial aneurysms.
CLIFTON
The person will be walking along the street, sometimes it's provoked by exercise, sudden exertion and it'll be like somebody's worst headache they've ever had, somebody hitting them on the back of the head with a sledgehammer. They will perhaps vomit, they'll collapse, go into coma or you may just get the bad headache and get a very stiff neck and photophobia. When that happens obviously the thing to do is to dial 999 and get yourself down to your nearest casualty.
PORTER
So the classic symptom of a burst intracranial aneurysm would be a sudden onset headache and depending on how severe the bleed everything from that right through to full unconsciousness. These people arrive in hospital, what happens next?
CLIFTON
Right. Very serious condition, 25% of patients, despite treatment, will die before they get to hospital. At the end of a series of treatments 25% will have a relatively normal life and the other 50% will vary from being heavily dependent to being able to live a relatively normal life.
PORTER
And what sort of people are more likely to develop these intracranial aneurysms?
CLIFTON
Well there's a female preponderance from between 60 and 70% of patients will be female. If you actually have got an aneurysm we know that there's a higher risk, perhaps 2:1, of the aneurysm bursting of the effects being worse if you smoke and also high blood pressure has about a 1.5% risk.
PORTER
So these bleeds can be pretty catastrophic. How big are these aneurysms that are bursting?
CLIFTON
You're talking the average size of the ones I treat are from two millimetres, which is very small, up to about one centimetre. And put that in perspective: if you look at the diameter of one of our pennies that's actually two centimetres. Studies have also shown, particularly a large one from the Mayo Clinic in the States, that aneurysms under five, six millimetres have a very, very low risk of rupture, perhaps less than 1.1% a year. So most patients will carry on with their aneurysm not knowing they've got it there and they'll die of something else such as heart disease or stroke or cancer, which are the commonest causes of death.
PORTER
But presumably it's not the size of the aneurysm that matters, it's the size of the bleed...
CLIFTON
Exactly.
PORTER
... they can produce large volumes of .. which presumably presses on the brain, surrounding brain?
CLIFTON
What it does is burst into the subarachnoid space, that's the space where the blood vessels live, where our brain fluid is and it increases the pressure dramatically on the surrounding brain structures and that's why the patient feels so unwell.
DOWNIE
It was a Sunday morning and I was playing in a tennis match at my local club and as I reached up to serve I felt a sudden ping in my head, which was like a thick elastic band snapping and then I suddenly became quite weak.
PORTER
Lauren Downie's aneurysm burst when she was 48.
DOWNIE
I started getting very shaky and I put my hand up to stop the game and call the others over to the net and as I walked to the net I realised my body was going into shock and the pain was absolutely excruciating....
PORTER
Headache.
DOWNIE
Yeah really unbelievable. My friends helped me into the clubhouse and all the light had become extraordinarily bright, my senses had completely changed in an instant. My neck had gone really, really stiff and I felt like I was going to be very, very sick in no time. I said my dad died of a brain haemorrhage and I think I'm having one. And they all looked at me completely aghast and in shock, unable to know what to do.
PORTER
Lauren's aneurysm was treated using a keyhole approach - the type of procedure performed by neuroradiologists like Andy Clifton.
CLIFTON
Patients stabilise, the next thing to do is to seal off the aneurysm.
PORTER
So a conventional approach would be to open the brain and clip or tie off that bleeding vessel?
CLIFTON
That's right but ...
PORTER
But you're going in through the artery. So how do you gain access to the artery?
CLIFTON
Under general anaesthetic because if you're talking about two millimetre aneurysms it's very, very sort of intricate stuff and if the patient moved more than about two millimetres the aneurysm might burst. So the patient's got to be very still. What I do is put a needle into the artery in the leg, the femoral artery, and then feed a tube or a catheter up into the target vessel, which is usually one of the vessels in the neck. We then use - using special road mapping - it's a bit like your Tom Tom but in the brain - I feed a very fine catheter into the aneurysm and then through that very fine catheter we've got various sort of tricks - we've got balloons, we've got stents but usually we just use coils - until the aneurysm's solidly packed and excluded from the circulation. Once it's excluded from the circulation it can't bleed again.
PORTER
And the success rate for that sort of procedure?
CLIFTON
Usually about 98%.
DOWNIE
I think it was Tuesday morning I came round and sat up in bed and my sister was there with my mother and they told me I'd had a brain operation and I thought they were all making it up. I couldn't make sense of anything.
PORTER
It was all a bit surreal.
DOWNIE
Totally surreal.
PORTER
Now how long ago was that?
DOWNIE
That was four years.
PORTER
I mean looking at you now if looks like you made a complete recovery ...
DOWNIE
I've been very fortunate.
PORTER
... have you been left with any form of deficit that you've noticed?
DOWNIE
No, I've been told that I haven't but you never quite know do you.
PORTER
Well it's one thing they told you, you haven't. Yeah but a lot of people complain of quite subtle changes but you've not noticed anything?
DOWNIE
Yes there were loads and they've taken quite a long time to overcome.
PORTER
Things like?
DOWNIE
Like concentration and actually being able to accept the situation and realise that you had to take it easy and actually listen to your brain.
PORTER
Lauren Downie, who has made an excellent recovery from her brain haemorrhage in 2004.
If you'd like to hear any part of the programme again then do visit the website at bbc.co.uk/radio4. Next week's programme is all about the kidney, including why blood in your urine is a serious symptom that should never be ignored.
ENDS
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