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BRITISH BROADCASTING CORPORATION
RADIO SCIENCE UNIT
CASE NOTES
Programme 2. - Heart Failure
RADIO 4
TUESDAY 17/01/06 2100-2130
PRESENTER:
MARK PORTER
CONTRIBUTORS:
MARTIN THOMAS
RACHEL JAMES
MALCOLM WALKER
JUDITH WALKER
MICHAEL FRENNEAUX
DAVID HILDICK SMITH
PRODUCER:
ADRIAN WASHBOURNE
NOT CHECKED AS BROADCAST
HEIDI
I got so bad that I could barely walk. The breathlessness I had and no energy and I couldn't sleep at night, I couldn't put my head down on the pillow, I had to sit up just to breathe. I'm on quite a lot of medication now but gradually it has improved. It's quite difficult to think back three years, I call it my previous life because lots of things have changed in my lifestyle.
PORTER
That was Heidi, one of 900,000 people in the UK thought to live with some degree of heart failure. In today's programme I'll be looking at how the latest technology is used to spot the condition - often before the patients themselves know there is anything wrong with their heart. And I'll be finding out how heart failure is treated - from simple but effective self-help measures like graded exercise, to a promising drug still in the pipeline, and a new type of pacemaker.
My guest today in the studio is Dr Martin Thomas, a specialist registrar at the Sussex Cardiac Centre.
Martin, before we talk about what goes wrong in heart failure perhaps we should start with what happens when the heart is beating normally. Talk me through a heart beat.
THOMAS
The heart is a muscle, it has four chambers, the two upper chambers which are called the atria, the two bottom chambers, which are called the ventricles. And the heart is split into two sides - the left and the right. The left side of the heart supplies oxygenated blood to the organs of the body and the right side of the heart supplies deoxygenated blood - that's blood with no oxygen in it - to the lungs to pick up its oxygen.
PORTER
So the atria are actually acting as priming pumps really for the large powerful ventricle.
THOMAS
They top up the filling of the bottom chambers.
PORTER
Now how's the - I mean it's a huge muscle, it has to contract in a coordinated fashion to make all that work properly - how's the contraction initiated?
THOMAS
There's a very fine network of essentially electrical cables through the heart which end up giving a coordinated electrical signal throughout the heart resulting in a coordinated contraction which is synchronised so the left and the right ventricles work at the same time, ensuring an adequate pump output to the heart.
PORTER
It's so complex, I mean in fact what's amazing is that it works as well as it does without letting us down. But what's actually happening when the heart fails?
THOMAS
Essentially the pump of the heart starts to fail and this just means that not enough oxygen is delivered to the tissues of the body. And as a result you end up with a lot of problems throughout different organs.
PORTER
So in a nut failure of the heart is not pumping enough, it's become inefficient, it's not meeting the demands of the body. What are the common causes?
THOMAS
The top one in the UK would be ischaemic heart disease, that's coronary disease, angina, heart attacks.
PORTER
Furring up of the blood supply to the heart.
THOMAS
Furring up of the blood supply resulting in not enough oxygen going to the muscle of the heart, so it becomes scarred, thinned and therefore cannot contract. The other major one would be hypertension - high blood pressure - which means that the heart becomes thickened and just can't pump so well.
PORTER
That's because it's having to work against the hard and normal pressure?
THOMAS
It's just the same as if you were trying to exercise and you're trying to push blood against greater resistance in the blood vessels and the muscle of the heart becomes thicker as a result.
PORTER
And that stops it working as efficiently.
THOMAS
Yep. And then there will be a more general batch, there's a group we call the idiopathic cardiomyopathies, which are a group of conditions where at present we don't know the exact nature of why the heart starts to fail. And then there are other causes, if you have valve disease, so that the chambers are separated by valves and if they start to fail you can get dysfunction of the heart muscle again. Things we do to ourselves, one of the major things would be over alcohol consumption and this essentially poisons the heart muscle.
PORTER
What about symptoms because at the lower extreme you might not have any symptoms at all but at the other extreme it can a very debilitating illness can't it?
THOMAS
To start off with I mean some people if you look at their heart the function of the heart is quite poor and they may have no symptoms at all. The most common symptom would be breathlessness when you exert yourself and also fatigue, tiredness and not being able to do what you would normally do and fluid retention.
PORTER
Swollen ankles.
THOMAS
Swollen ankles. And also if fluid retention starts to develop in the lungs you become more breathless as a result of that.
PORTER
And that classically presents at night initially, isn't it, people find it difficult when they lie flat they notice ...
THOMAS
Absolutely. And the reason for that is when you lie flat more blood sloshes back to your heart and your heart just can't cope with that and you become breathless.
PORTER
Now what about diagnosis, obviously we get a clue from the story, we can examine the patient, we can do an electrical test - an ECG - and we can do a chest x-ray all of which can point towards problems but the definitive way is to use ultrasound.
THOMAS
Yes, all the things you mentioned give us clues but the way to actually look to see whether the pump of the heart is working properly is by what's called an echocardiogram. Which is an ultrasound device that most people would recognise as pregnant ladies having a look at their babies that uses exactly the same techniques but slightly enhanced to look at the contraction of the heart and also flow dynamics ...
PORTER
Instead of looking at the baby we're looking at the heart.
Well Dr Rachael James is a consultant cardiologist at the Royal Sussex County Hospital. I joined her at a busy morning clinic where, before introducing me to someone with heart failure, she rather wisely decided to remind me what a healthy heart looks like.
JAMES
This is probably the most easily interpretable, this is the four chamber view, it's a bit like a valentine cut through the heart and these are the two chambers, the pumping chambers of the heart, the left and right ventricles with the two atria. And here we can see the normal elliptical egg shaped left ventricle with good function and all the walls are contracting equally.
PORTER
It's actually very easy to see isn't it, it's just a pure cross section right across the middle.
JAMES
And we can see a real time moving image with the heart in three dimensions. And this has been a major step forward in the field of echocardiography and this builds up a sort of cast, a mathematical model of the heart moving.
PORTER
There's a massive difference between - I mean that surprises me, I've never seen an image like that before. What sort of percent - the heart almost looks like it's almost doubling in size.
JAMES
Yes, this lady has an [indistinct words] 65%, that's a measure of the overall pumping action of the heart and it's pumping well. You can also look at little different segments of the heart and how they're moving in relation to one another. We've divided up the left ventricle, the main pump of the heart, into say 16 segments, we'd expect them to all contract at the same time and relax at the same time. And this is shown here graphically as a curve over time.
PORTER
So if part of the muscle is not contracting in a coordinated fashion that could be, presumably, either because there's some problem with the electrical supply to it or the muscle itself?
JAMES
Absolutely or a component of both.
Right, sir can you sit nice and well up on the coach, keep going.
PATIENT
More? That's made me breathless.
JAMES
I can tell. Right sir some cold jelly on the probes that may be a bit nippy and I do need to press. We look at the four chambers, the Valentine cut through the heart we saw compared to the normal, here we see first of all a dilated left ventricle, it's much bigger than the person with the normal function, it's also somewhat changed its shape - it's lost that elliptical and it's much more a sort of globular or football shape and the whole thing has a sort of rocking appearance rather than contracting down.
PORTER
There isn't a lot of contraction going on is there.
JAMES
No. One very common thing when the ventricle is so enlarged and abnormal is for there to be a leak on the valve that's related to that chamber which is the mitral valve and you get regurgitation which also can affect breathing.
PORTER
So that's effectively blood flowing backwards through the heart. So the valves there that when the ventricle contracts it shoots blood out of the heart rather than back up into the priming chamber, the atrium.
JAMES
So you've not only not got good flow from the ventricle due to the pump abnormality but you've also got a back flow of ...
PORTER
A proportion of that is going the wrong way.
JAMES
Absolutely.
Right, so this is 3D echo now, it's done in real time, we can see the ventricle beating but in three dimensions. And if we look at different areas of segments, so this is looking at the movement of different areas of the ventricle, the ventricle is arbitrarily divided into 16 segments. We're looking at the movement of one segment in relation to the other, the most notable thing is that compared to the other ventricle it's highly discordinate, so at times where you've actually got contraction we've got areas even moving in an out ways fashion rather than actually contracting.
PORTER
So while some fibres are being - contracting, some are being stretched.
JAMES
Absolutely.
PORTER
And can you tell the difference by looking at an echocardiogram as to the actual underlying cause of that disruption?
JAMES
We can sometimes if we see an area of thinning or scarring that would suggest that the patient's had a heart attack in that area or areas of muscle which are not working as well in a particular territory it may suggest underlying coronary disease.
PORTER
Dr Rachael James in the echocardiography suite in Brighton. You are listening to Case Notes, I'm Dr Mark Porter and I am discussing heart failure with my guest cardiologist Martin Thomas.
Martin, presumably, in most cases of heart failure, the underlying cause - such as damage to the heart wall from a heart attack - is irreversible so it can't be cured.
THOMAS
In some cases it can be cured and they're few cases but if you have valve disease, so there's a blockage between the two chambers of the heart causing a restriction to flow by surgically correcting that you can cure the condition. But in general it's not. So we have to do things to try and improve overall quality of life.
PORTER
Well let's start right at the beginning. I mean what can the patients do to help themselves?
THOMAS
There're very general things, they can reduce the amount of salt they take in their diet, they can cut down the amount of fluid they take in, they can improve their diets. And one of the good things that's coming along is some exercise, that will improve matters.
PORTER
And what's the evidence that those self-help measures make any difference?
THOMAS
There are definitely some studies coming along showing the benefits of exercise programmes in outcome from heart failure.
PORTER
Well Dr MalcolmWalker, consultant cardiologist at the London Heart Hospital, heads up such a study, and is currently investigating the benefits of exercise in people with heart failure.
WALKER
One of the non-medical aspects of care for patients with heart failure, with a pump that's not efficient, is to make them fitter - they do better.
PORTER
What sort of degree are we talking about?
WALKER
It's very variable but what's dramatic is that the patients most seriously affected are the ones that notice the biggest benefit and perhaps that's not surprising. Those individuals that could barely walk a few yards suddenly find that they're able to contemplate socialising, leaving their home, go out, do shopping - do the normal things of life. One particular patient involved in this study, who was a patient I was looking after, was on a waiting list for a cardiac transplantation, and at his own request was taken off that list because he felt perfectly well enough now to resume normal activities and life.
PORTER
What's actually going on, is it affecting the heart or is it the rest of the body that's benefiting from this?
WALKER
This is a difficult point but it's not fully established. I think clearly in the shorter term what's happening is that you're making the skeleton, the muscular skeletal system, the muscles in particular, stronger, so the body's more efficient, so it demands less of the heart for any degree of exercise. And that has a huge advantage to a heart that perhaps is not pumping efficiently.
ACTUALITY - EXERCISE CLASS
PORTER
Judith Walker is the Cardiovascular Health and Rehabilitation coordinator at University College Hospital where the exercise classes are held.
JUDITH WALKER
They come along to us for 12 weeks, they come once a week in the afternoon. And during that time they'll be, as you can see, doing things - very simple exercises. It all varies because some of them are more capable than others so that's very much down to the initial assessment that we do beforehand.
PORTER
So you can tailor the programme towards the individual.
JUDITH WALKER
Yes.
PORTER
The class, I know we've got 10 people here today or thereabouts, there's quite a lot of difference in what they can actually do and indeed in their ages as well.
JUDITH WALKER
That's very true and one way of actually being able to assess or putting patients into categories of risk is by performing something called a six minute walk test, which is very simple but we do at the beginning of a - patients coming on to the exercise programme. And a good guide is if they can do more than 200 metres on a six minute walk test then normally they're quite capable of doing an exercise class as you can see today.
ACTUALITY - EXERCISE CLASS
PORTER
So they're starting off over here, what are they doing there - they're just lifting - they're bending their legs at the knees basically, kickbacks.
JUDITH WALKER
Yes that's right, kickbacks, so this is actually strengthening the big quadriceps muscles on the top of your legs. So we teach them to do them in a gym but we'll actually teach them to incorporate them into their lifestyle at home, so they can watch the TV and do their leg raises.
PATIENT
I do an hour's exercise every morning now.
PORTER
So you come to the class once a week and you're doing something everyday at home as well?
PATIENT
I do an hour, yeah, I do between 7 and 8 in the morning.
PORTER
And now you're starting to do exercise are you finding that it's improving your stamina?
PATIENT
Yeah well definitely, yeah and I can sleep a lot better.
PATIENT
I just well yes - soon as I master the kickback it's a bit slow ...
PORTER
A bit of a coordination problem have you?
PATIENT
Yeah struggling with the back muscles.
PORTER
I'm glad you're benefiting from it.
PATIENT
Oh god yes, yes. I manage to run away from the wife, when she wants to [indistinct word] I run away.
WALKER
We did a national survey recently and most rehabilitation programmes which were set up primarily to deal with people following heart attack and heart surgery will aspire to provide the service but at the moment it's very, very patchy and there are very few units that have been able to build it in to standard care of heart failure patients. We hope that's going to change, as more and more information gets out there people become confident that this is safe, it's practical, yields very good results, then they will develop and be much more widely taken up.
PORTER
Do you retest them at the end of the programme to see whether their physical endurance has improved?
JUDITH WALKER
Yes we do, we do functional tests, we do a simple six minute walk tests. It's not a huge improvement and it may not be truly reflected in the six minute walk tests but what you will find is their physical activity diary that they're filling in at home they're actually doing a lot more than they did when they first came.
PORTER
What about the socioeconomic side, I mean looking at it from the hospital's point of view, investing in a programme like yours, I mean as well as the human benefit, in terms of symptom relief, is there actually any evidence that patients, for instance, are better, require less hospitalisation?
WALKER
There is some evidence to that, what we call in medical terms, morbidity, that is all the attendant problems that are associated with severe illnesses, that is the amount of time you have to visit your doctor, the number of times you're admitted to hospital with a worsening in your condition - those are significantly improved if people become fitter and are part of these programmes. They feel better and in some respects less of a drain on the resources, all in all it's a win/win situation.
PORTER
Cardiologist Dr Malcolm Walker.
Martin, we've heard about exercise there, what other treatments do we have?
THOMAS
The mainstay treatment is tablets and there are three main classes - either diuretics or water tablets and the other two are called ACE inhibitors and beta-blockers.
PORTER
Well let's start with diuretics. Are they simply working presumably by reducing the load on the heart by getting rid of excess water?
THOMAS
Yeah, they're nice simple drugs - get rid of the fluid. But unfortunately they have no improvement in mortality from the condition.
PORTER
So it might make people feel better but they're not doing a lot of good for the underlying condition, they're covering it up.
THOMAS
Not at all.
PORTER
Okay, moving on to ACE inhibitors.
THOMAS
ACE inhibitors were the new drug that came along, that made a significant impact into mortality from people with heart failure. And these work essentially by dilating the blood vessels so there's less pressure on the heart, so it can work better.
PORTER
And these are the drugs that end in il aren't they, so it's Captopril, Enalapril, Ramipril - those sorts of drugs. And last but not least beta-blockers. Now when I was at medical school beta-blockers is sort of like an anti-adrenaline drug, if you like, they actually slow the heart down and make beats - they make it weaker. Why would you be using those in heart failure?
THOMAS
Well it was a brave person that first introduced them and it was counterintuitive that these drugs which would slow the heart rate would do bad things for the heart muscle. But because of its anti-sympathetic activity, its anti-adrenaline activity, it calms the heart down. Most of its impact is from the reduction in arrhythmias, so funny heart rhythms that cause sudden death in people with heart failure.
PORTER
So looking at all of those treatments together, we talked about symptom relief versus mortality and morbidity, they obviously make people feel better, one would hope. What sort of impact do they have on things like hospital readmission rates and long term prognosis?
THOMAS
The ACE inhibitors and the beta-blockers have a clear reduction in mortality of around 30% which is a big figure in this group. However, we do know that the maximum benefit is gained from being on the top doses of all of these drugs.
PORTER
Which brings me nicely on to the fact that these, along with a number of other conditions now, heart failure is subject to strict protocols that are often managed by nurses rather than doctors and that's helped hasn't it.
THOMAS
Absolutely. The heart failure nurse specialists have become an integral part of the care team for people with heart failure. Not only from an educational point of view - telling the patients what they need to do - but making sure that the tablets are up titratus, so they get on to the top doses of all the drugs that they need. And this has a clear impact on readmissions with heart failure, morbidity, mortality and especially quality of life.
PORTER
Nurses are better at doctors than getting patients on to the right drugs at the right doses is often the case yeah. Well diuretics, ACE inhibitors and beta-blockers form the mainstay of treatment but there is at least one new drug in the pipeline. Michael Frenneaux is the British Heart Foundation Professor of Cardiology at Birmingham University, and leading research into perhexiline - a drug that works in a very different way to existing treatments.
FRENNEAUX
Perhexilene is a drug which works by switching the fuel that the heart uses to generate its energy. So it switches its fuel from fat to sugars. And that results in more energy production. And presumably that's why when we add it to these existing drugs it's so effective because it's working by a different mechanism.
PORTER
So it's basically improving the efficiency of the heart. What knock on effects have you noticed in your clinical trials?
FRENNEAUX
Well the study measured exercise capacity and there were very dramatic improvements in exercise capacity. A patient who could only walk slowly on the flat might expect to now be able to climb stairs without too much difficulty - that's the sort of magnitude of benefit.
PORTER
Where exactly in the pipeline are we, if the trials prove as exciting as you're suggesting, when might the drug be available?
FRENNEAUX
Well in order for a drug to be readily available to the average doctor in the street, as it were, it has to have been shown in a large trial to reduce either the death rate or the hospitalisation for heart failure, that's generally the criterion that's used, and that requires a very, very large study. So we're at the moment trying to negotiate for such a study and so that's the stage we're at at the moment.
PORTER
Professor Michael Frenneaux.
Drugs aren't the only way to treat heart failure. Advances in pacing techniques now mean that artificial pacemakers can override a diseased heart's natural rhythm and resynchronise poorly coordinated contractions of the ventricles. A technique called cardiac resynchronisation therapy. The Royal Sussex County is one of a growing number of hospitals using the technique. Cardiologist Dr David Hildick Smith.
HILDICK SMITH
In heart failure research over the last 10 years has shown that if patients have poor heart function overall, particularly if the left ventricle, the main pumping chamber which sends the blood round the body, if they have poor left ventricular function and an electrical abnormality on their basic heart tracing, which shows that the electrical impulse is not going down the normal channels, then they may be suitable for a type of therapy called biventricular pacing or alternatively called cardiac resynchronisation therapy whereby three leads are used in the heart in order to resynchronise the way the heart pumps. It's an extension of pacing technologies that have been around for 40 years, whereby we use instead of what is currently used at single or perhaps two leads to pace the right ventricle in biventricular pacing there'll be a third lead added to pace the left ventricle.
PORTER
Mr Harvey's come in for a biventricular pacemaker. He was diagnosed with severe heart failure eight months ago.
HARVEY
I was in Conquest Hospital, Hastings for 10 days and then I became alright. Then about a month later I was moved back in here again with the same complaint, that was four times I done that. But I can't walk like I used to, I can't go down the pub I have to get a taxi to take me down, though that ain't far, it's only about 500 yards.
HILDICK SMITH
We're all setting up now for the procedure of Mr Harvey's line now we're reasonably comfortable. So basically over the top of the shoulder there's a little vein there called the cephalic vein which runs in the shoulder groove. We'll be using that for one of the leads and the other leads will go into the subclavian vein which is just under the collar bone. There we've got on screen a silhouette of the heart, you can see, and the lead - the right ventricular lead there is just - at the moment it's in the right atrium, just being advanced down towards the right ventricle. So this bit is all just like it would be for a normal pacing procedure, this is no different. The different bit will come once we've put this lead in and go to try and find the coronary sinus to put that lead in but this is all as per a standard pacing procedure.
So you essentially have a triple pronged approach to electrical activation of the heart. And this means that instead of a creeping wave of muscular activity, which results in this discordinate and inefficient working of the heart, actually what you get is three points pretty much simultaneously asking the heart to pump and thereby you get a much more efficient overall output from the left ventricle in particular.
So we're looking for the coronary sinus, I think we've seen a hint of it there, and now we're taking a lubricious wire into the coronary sinus, higher on the lateral wall of the heart. And what we do now is we take a picture with some contrast to see what array of venous tributaries there are to this lead because we have to choose one of them. So this is one of those moments of truth in a biventricular procedure. Let's go on to monster mag. That's what's known as a dearth of suitable veins. What we're looking for is a big vein and that's sort of distinctly lacking there just at the moment, so we're going to have to search a bit further. Oh that's lovely, yeah that's good. Okay I was lying there's a good vein there. I think we'll try that now.
You'll see really quite a dramatic benefit, a sort of 30% improvement, in people's exercise capacity and six minute walk capacity when they've got the biventricular system in. Certainly we're very pleased locally with the results we've had, we've done this procedure on 90 patients in the last three years and these improvements seem to be well maintained over time. We're sort of waiting in a sense to see the more long term results.
Are you alright, are you comfortable?
HARVEY
I'm alright yeah.
HILDICK SMITH
Good. It's all gone very nicely, we've got all the leads in position and we're just finally sewing up the pocket now.
It's increasingly a technology which will be more widely available and there'll definitely be capacity for this to devolve out to the surrounding hospitals. I mean it's now got to the point where I'm very disappointed if I see somebody in clinic after they've had a biventricular pacemaker and it's really not made any significant difference to their symptoms.
PORTER
Cardiologist Dr David Hildick Smith.
Martin, that sort of pacing must be very exciting but it's only ever going to be offered to a small minority of patients isn't it?
THOMAS
At this point in time yes, but I think over the coming years it will be rolled out to far more people with heart failure.
PORTER
Do you think many more would benefit from it?
THOMAS
Absolutely.
PORTER
Martin, we haven't really discussed the long term outlook for people with heart failure, it can be pretty bleak can't it.
THOMAS
It is, anywhere between 10 and 60% of patients with heart failure will be dead at a year of their diagnosis, which is a grim figure.
PORTER
I mean that compares, probably worse actually, than most of the common cancers. When you're talking to people about heart failure do you think they realise how serious their symptoms are?
THOMAS
No because their symptoms are quite mild - they're just a bit tired or a little bit breathless - so it's a gradual process of informing your patient as to the severity of their condition.
PORTER
And what about care in the community, I mean if you've got cancer and you're not expected to survive a long time it's quite easy to get the sort of help that you need, the palliative care that you need, but someone with severe heart failure, in my experience, that can be tricky.
THOMAS
There is no palliative care network for heart failure patients at the moment. There are a few places that are developing this and it's very useful but it's not widespread throughout the country.
PORTER
On a lighter note, heart failure may be incurable in most cases, as we've heard, but a lot of the things that cause it, things like high blood pressure, the furring up of your coronary arteries, those are essentially preventable diseases, do you think that our current more aggressive intervention to things like diabetes and smoking and high cholesterol levels and treating high blood pressure will have a knock on effect that eventually we'll see a reduction in the number of people with heart failure?
THOMAS
I think we probably will alter the type of patient that we're getting with heart failure because at the end of the day heart failure is the end stage of all cardiac conditions. So although we might reduce the people with ischaemic heart disease as a cause, other things will come along and replace that.
PORTER
So one would hope though that people will be developing this condition much later in life than perhaps they are now?
THOMAS
Much later yeah.
PORTER
We must leave it there. Dr Martin Thomas thank you very much.
Don't forget if you would like to listen to any part of the programme again then do visit the website at bbc.co.uk/radio4.
Now at the end of the last series I asked you to send in ideas for this series - either by post or e-mail - and back pain proved a popular choice. So that's what we're doing next week. I'll be finding out when surgery can help, and when it can't, and why people who follow a holistic approach to their back pain tend to fair better.
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