At last! The implant that makes it safe for heart patients to have vital MRI scans
£20,000 device can be ‘switched off’ for lifesaving checks
A£20,000 heart implant that allows patients to have lifesaving MRI scans – which can damage traditional devices – is now being offered on the NHS. The technological advance means that thousands of people with abnormal heartbeats can now undergo these ‘gold-standard’ health checks without risk.
Previously, people with pacemakers and implantable cardioverter defibrillators (ICDs), which send electrical pulses to the heart to change a fatal rhythm into a normal one, were denied MRIs because they use a magnetic field that can stop the metal leads used in the devices working properly.
Currently, more than 6,000 people a year in the UK receive ICDs, although this figure is set to increase after the National Institute for Health and Care Excellence updated its guidelines meaning more people now qualify for one.
Of these, almost two-thirds will need an MRI scan within ten years of receiving a device. The scans allow doctors to view detailed images of internal organs and blood vessels, and are essential in diagnosing additional heart problems, cancer and even diseases such as Alzheimer’s.
Until now, the powerful magnetic fields and radio waves used by MRI scanners risked causing the implants to deliver an unnecessary shock or heat up and burn the heart tissue. Instead, people have been limited to less sophisticated screening such as X-rays and ultrasound scans, leading to delays in diagnosis.
But the new ICD – the Evera MRI SureScan – allows doctors to carry out MRIs on any part of the body including the heart.
Developed in the US over a decade, the battery-operated device has special software to protect the ICD from the scan’s magnetic field and buffers any interference. Using a wireless laptop, the doctor can reprogramme the 2in-long ICD before a scan, ‘blinding’ it from detecting abnormal heart rhythms during this time. The latest device costs twice as much as traditional implants.
Penelope Wybrow is one of the first patients in the world to benefit from the new-style implant, which is the size of a matchbox and sits just under the muscle below the collarbone.
The 41-year-old has cardiomyopathy, a condition that causes the heart muscle to thicken and weaken over time, making it less able to maintain a normal rhythm. This puts her at risk of the heart stopping suddenly.
The mother of two, who is a carer for the elderly and for disabled children, was diagnosed in 1996 after suffering blackouts, and she was put on drugs to decrease the activity of her heart.
Doctors considered her suitable for this new ICD as her condition is progressive, so she has a high chance of needing an MRI scan.
Penelope, who lives on a canal boat in Hillingdon, North-West London, said: ‘I feel I could live for ever now. It’s given me complete peace of mind. Before, I was scared of taking any exercise or even picking something up – I couldn’t live my life to the full.
‘But this is like having my own personal paramedic which will respond faster than an ambulance and restart my heart.
‘It also means doctors can perform an MRI, which is vital because they can check if my condition is getting worse and give me treatment at the earliest possible stage.
‘Without it, I would have been able to have an X-ray, for example, but these don’t give such a clear and detailed picture.’
Her operation was carried out in April by Dr Mark Mason, a consultant cardiologist at Harefield Hospital in London. Other hospitals now offering the device to patients include Wythenshawe Hospital in Manchester.
During the 45-minute procedure, carried out under local anaesthetic, a small incision is made in the left side of the chest to create a pocket in the muscle to hold the ICD. Two wires leading from it are threaded through the incision into a vein in the upper chest and through this into the top and bottom of the heart’s chambers, where they are embedded into the muscle.
The patient is sedated while the heart is stopped briefly to test the ICD. Finally, the incision is closed using dissolvable stitches.
Dr Mason said: ‘This device means patients can undergo MRI scans, which are the now the gold standard for diagnosing life-threatening or disabling conditions such as spinal problems. Thousands were denied these scans before, which led to delays in diagnosis and treatment. The NHS will also potentially save money through people being diagnosed earlier.’