Icy balloon to help calm a racing heart
MORE than a million Britons have a heart rhythm problem known as atrial fibrillation. Philip Cale, 36, a community mental health nurse from Worcester, in the West Midlands, underwent a new procedure for it, as he tells SOPHIE GOODCHILD.
THE day after my work Christmas party in December 2016, I woke up and noticed my chest was fluttering. I thought perhaps I had overdone it — I don’t drink but I had come home around midnight.
However, as I’m otherwise fit and healthy, I got on with the day as usual, getting my two daughters, aged nine and three, up and then sitting down for a cup of tea with my wife, Catherine. Like me, she is a mental health nurse and has advanced training in resuscitation. When I told her that my chest felt funny, she dialled 111 and they advised me to go to A&E.
My pulse was around 170 to 200 beats a minute, more than double the normal heart rate (60-100 at rest). Despite me not drinking or taking drugs, the A&E staff were convinced I must have done because heart rhythm issues are rare if you’re under 40, but blood tests showed I’d been telling the truth.
Next I had an electrocardiogram (ECG), which measures the heart’s electrical activity and I was diagnosed with atrial fibrillation. I knew this meant an abnormally fast heart rhythm, which was worrying.
They gave me a beta blocker to slow my heart but it made no difference, so I was admitted to the resuscitation unit. The colour drained from Catherine’s face when they told us: resus is for seriously ill patients.
I was sedated and the medical team then used a defibrillator to shock my heart into a normal rhythm. When I came round it was no longer racing.
A few weeks later I saw a cardiologist who said not to worry because people my age don’t get atrial fibrillation and that it was probably a one-off.
HoWEvEr, on Good Friday last year I woke up with the same strange sensation in my chest: we were on holiday in Norfolk and went to the local hospital. The symptoms lasted four hours but then stopped. Clearly it wasn’t a one-off.
My GP referred me back to the hospital in May. This time my pulse was constantly erratic, I had stabbing pains in my chest, lasting up to a couple of minutes, and my energy levels were so low that the ten-minute walk to my daughter’s school would take me 20. I had to be signed off work.
At my appointment, I was told about a new procedure where they freeze the area triggering the abnormal heart rhythm. The cardiac nurse said it was better than doing it with heat, which is the usual way, as this can damage blood vessels.
Hearing that something could be done made me feel better. The downside was a 12-month wait for treatment at a specialist centre in Coventry. But then, six months later, I was told that my local hospital could do it.
I had the procedure at the end of February. I had a local anaesthetic in my right thigh and then they pushed wires and tubes up through my groin: I could feel this happening, but it wasn’t painful. I was in hospital for 12 hours.
The next day, at home, I woke up sore at the top of my leg and it was purple with bruising.
My consultant said it would be six to eight weeks before I noticed any change as the heart is swollen from the procedure so it takes time to settle down to a normal rhythm. The palpitations gradually reduced and I hardly get them now. I’m still on medication but hope to be able to stop the beta blockers soon.
No one knows why I developed atrial fibrillation so young, but I feel back to my normal self and it takes me ten minutes, not 20, to take my daughter to school.
THE SPECIALIST
will FosTeR is a consultant cardiologist and electrophysiologist at worcestershire Royal Hospital. THE most common type of faulty heart rhythm, atrial fibrillation (AF), causes an irregular and often fast heartbeat. The resting heart rate can soar up to 400 beats a minute.
It’s rare in the under-40s. Increasing age is a factor, with a quarter of people in their 90s suffering from it. Wear and tear causes heart tissue to thin and stretch. Alcohol and high blood pressure are also factors: the theory is they stress the heart.
Being extremely fit, like a marathon runner, increases the risk by triggering damage and a build-up of scar tissue.
The heart’s natural pacemaker, the sinus node, is an area of cells in the upper right chamber. This fires off regular electrical impulses, causing the left and right top chambers (the atria) to contract and pump blood into the bottom chambers (the ventricles). These impulses spread from the top of the heart to the bottom, causing the muscle to contract and pump blood to the body.
With AF, abnormal rapid pulses fire off from one or all four (pulmonary) veins leading from the lungs to the heart. These rogue pulses originate in the ‘sleeves’ of muscle covering the base of the pulmonary veins.
The pulses override the heart’s natural rhythm, so the atria contract randomly and rapidly out of sync with the bottom chambers. This reduces the heart’s ability to pump blood, which then pools in the heart leading to clots that can break off and travel to the brain, increasing the risk of stroke.
Blood-thinning drugs or other medications combat clots effectively while beta-blockers, which block stress hormones like adrenaline, make the heart beat more slowly, reducing the palpitations.
Philip had a type of AF (paroxysmal or PAF) which occurs at weekly intervals or every few months, but causes extreme symptoms such as palpitations, crippling lethargy and chest pain. Most people start with this type, then it progresses to more frequent and more prolonged.
Cryoballoon therapy can transform those patients’ quality of life; they still need blood thinners for stroke prevention but they can stop medication such as beta-blockers (which can cause lethargy, and impotence in men).
ATINy balloon filled with gas that’s then cooled is used to freeze a ring of scar tissue around each pulmonary vein to block the rogue electrical signals. It’s quicker than existing techniques, where radiofrequency is used to burn the tissue. This takes three hours compared to 90 minutes for the cryoballoon.
With radiofrequency, you have to carefully steer the wire around the vein in a continuous line — effectively ‘drawing’ the line of scar tissue — and it’s easy to make a hole by burning or pushing too hard with a wire. While the complication rate is fairly similar, with the balloon any complications are less severe.
We sedate the patient then insert a long tube up to the left atrium via the vein at the top of the right leg. A 10mm balloon on the end of a tube goes into the heart. Attached to the end of the balloon is a circular wire coil with sensors to pinpoint the electrical signals in the pulmonary vein.
With the balloon in position, refrigerated gas is then pumped into it: the freezing takes 180 seconds. When cold, the curved middle of the balloon sticks to the surface of the vein walls.
We monitor the electrical signals in the vein using the circular coil, and if the signals disappear this indicates the vein has been successfully isolated. Then we stop pumping in the gas and the warmth of the blood flow thaws the ice. The freeze/ thaw creates a 1mm diameter circle of scar tissue and it’s this that blocks the rogue signals. We treat all four pulmonary veins.
A study published in the New England Journal of Medicine in 2016 concluded that cryoballoon therapy was safe and as effective as radiofrequency. It’s suitable for people who have not benefited from medication, who have intermittent AF with severe symptoms and whose condition is not long-standing. THe operation costs £6,000 on the nHs, £12,000 privately.