Metal tubes in your leg to stop fatal blood clots coming back
TREATMENT for a deep vein thrombosis (DVT) — a blood clot in a large vein — can involve taking drugs for life. Katalin Portik-Szabo, 36, a nanny from London, had a new surgical alternative, as she tells OONA MASHTA.
Three years ago, my left calf started swelling from time to time. But one day in November 2014, my entire leg suddenly swelled all the way from my foot to my groin. It was so swollen I couldn’t put on my boots and I could hardly walk as I also had terrible pain in my lower back. It was very scary.
My GP sent me for an X-ray and an ultrasound, but they found nothing. The swelling didn’t go and after six months I had to give up my job because I couldn’t walk and play with the children I was looking after as my leg was so painful.
Over the next year, I saw many doctors at several hospitals, but no one could explain my condition. eventually, I asked to be referred to University College hospital as it has such a good reputation.
In June 2015, I saw Professor Toby richards, a consultant vascular surgeon, who just from looking at my leg said he was 90 per cent sure I had May-Thurner syndrome, where a vein in the leg is compressed and blocked by an artery.
The swelling was a result of blood pooling in my legs — and this had led to a DVT. I had an ultrasound scan to be certain.
Professor richards offered me the chance to take part in a study for a new treatment that would hold open the damaged vein. This would allow blood to flow normally and help to prevent another DVT. I had the operation under general anaesthetic in January 2016. I saw and felt the difference straight away — I could walk without any pain and the swelling reduced dramatically.
I left hospital the next day. From then on, I had to walk a minimum of three miles a day and had to take anticoagulant medication for five months to thin my blood while the stent (the mesh tube holding the vein open) properly bedded.
My recovery has been incredible. I can go out, enjoy my life and wear boots again. I can go to work, too. I’ve got my life back.
THE SURGEON Professor Toby richards is a consultant vascular surgeon at University College London Hospitals NHs foundation Trust.
eVery year, more than 60,000 Britons develop a DVT — a blood clot that forms in one of the deep veins of the leg.
Typically it causes swelling, pain during exercise and sometimes leg ulceration.
DVTs usually affect one leg. In severe cases, the clot can break off and travel to the lungs, triggering a potentially fatal pulmonary embolism (where the clot blocks the pulmonary artery that carries blood from the heart to the lungs). Left untreated, about one in ten people with a DVT would develop a pulmonary embolism.
There are three main causes of a DVT: obstruction of blood flow, damage to the vein wall or sticky blood — brought about, for example, by certain medications, pregnancy or a genetic predisposition.
Immobility can also be a cause, because if you are not standing up and walking around, you are not pumping blood from your calves.
Katalin had a different problem: May-Thurner syndrome. It’s caused by the main blood vessel in the leg, the iliac vein, becoming squeezed between an artery and the spine — a problem that may be present from birth.
As a result, the flow of blood is obstructed and the vein wall is damaged, which increases the risk of a DVT. Usually, a DVT is treated with strong bloodthinning drugs, such as warfarin, which dissolve the clot and stop it blocking any more of the vein or moving to the lung.
But a DVT can leave permanent damage, causing an obstruction that could encourage further clots.
To avoid this, patients may be prescribed warfarin for several months or — if there was a large DVT — for life. But this requires regular blood tests to check that you’re receiving the correct dose.
My team is conducting a trial of a pioneering technique that can be used for all DVTs in which we use stents to hold open damaged veins.
The operation takes only 90 minutes and frees patients from life-long drug treatments.
Many people already have stents opening arteries in their hearts, but keeping a vein open is harder because it is so much bigger and collapses more easily. Now, thanks to improved imaging and surgical techniques, as well as newer types of stent, it is possible.
The stents we use are almost 5in long (heart versions are usually just a few millimetres) and are made from a titaniumnickel compound invented by NAsA. Patients need between one and three stents, depending on the extent of damage. Katalin had only one.
They are placed while the patient is under general anaesthetic, using keyhole surgery.
First, we insert a catheter (a thin, flexible tube) and a wire through the back of the knee and glide them to the blockage — the clot is normally between the belly button and groin.
Then we use a miniature machine called an intravascular ultrasound that goes inside the vein and scans it to show the damage. This helps to ensure we fully treat any problems.
Once that is done, we inflate a small balloon on the wire to open the blocked vein.
Then a stent is passed along the tube and released into the vein to keep it open after the balloon is deflated. This means that blood can flow normally into the vein.
Over the next six weeks, cells grow over the stent and hold it in place. We keep patients on blood-thinning drugs for up to 12 months.
University College hospital’s clinical trial is part of an international one, which has tested the stents on more than 200 patients.
The overall findings are due to be published next year, but they are expected to reveal successful results.
WHAT ARE THE RISKS? The operation can damage veins, weakening them. A sTeNT can stop the blood flow, causing other DVTs.
sAID ABIsI, a consultant vascular surgeon at Guy’s and st Thomas’ Nhs Foundation Trust, says: ‘The procedure is only for major DVTs, not minor ones. It is expected to benefit one in ten patients.
‘Not all DVTs need stents, as they can be treated with bloodthinning drugs. The main risk is bleeding.’ THe stents cost about £2,500 each.