Posted on Friday 27 January 2017
Tiny wireless heart device
The tiny wireless heart device is the same size as a grain of rice.
A cutting-edge device the size of a grain of rice is being used by experts at Guy’s and St Thomas’ to help patients with heart failure.
Unlike conventional devices, the innovative implant has no leads and is placed directly inside the heart tissue. This makes it work more efficiently and over time the heart’s lining grows over it, so it becomes part of the heart.
The team at St Thomas’ is one of only three around the country to use the implant, which is known as WiSE technology and developed by EBR Systems. Lead failures can cause complications so it is believed that the wireless device could be better for patients.
Experts at the hospital have worked with Siemens to create an image guidance system unique to the Trust which combines MRI (magnetic resonance imaging) and ultrasound imaging to create a detailed map of the heart. As a result, they can find the best place for the device to work as effectively as possible.
Professor Aldo Rinaldi, consultant cardiologist and professor of cardiac electrophysiology, said: “This type of device, known as a cardiac resynchronisation (CRT) device, is always placed inside the left ventricle which is the chamber that pumps oxygenated blood to organs around the body. Where we place it can affect how well it responds so our precise imaging system is very important. For example, some patients who have had a heart attack may have scarring inside the heart and the device won’t work well if it’s put there.”
Frances Rodgers was one of the first patients to have the new device implanted in September 2016. The grandmother-of-six from Dartford, Kent, has atrial fibrillation, a condition that causes an irregular and often abnormally fast heart rate.
Frances, 70, said: “I had another device fitted in 2000 but in 2015 I started to get very breathless so my doctor said I needed an upgrade which required another lead to be put in. But they couldn’t get it in because one of my heart valves had narrowed and although they tried their best, I was told nothing more could be done.
“By that point I was struggling to go up the steps to reach my front door and I was sleeping 18 hours a day. Then my doctor at Darent Valley Hospital told me that Professor Rinaldi was implanting a revolutionary device at St Thomas’, which I could have because it had no leads, and he put my name forward for it.
“I can’t believe how much difference the procedure has made. I’m not breathless, I sleep less, I can walk further and seeing friends and family is easier. It’s a miracle.”
Heart failure can mean that the pumping chambers (the left and right ventricles) inside patients’ hearts do not contract at the same time, reducing the amount of blood pumped around the body with every heartbeat.
CRT devices synchronise the contraction of both sides of the heart. Conventionally they are placed under the skin in the upper chest and are linked to wires that feed into the right and left ventricles. But it is thought that around a third of patients do not benefit from them, with lead failures being the main complication.
In order to implant the new device, patients first have a matchbox-sized generator implanted between their ribs, which sends out ultrasound impulses. In a separate procedure, a catheter (a long, thin tube) is inserted into an artery in the groin and is guided to the heart, where the device is positioned. It then converts the ultrasound waves into electrical pulses which keep the heart’s ventricles pumping in sync.
Professor Rinaldi added: “The new device seems very promising for patients so far. At the moment it’s being used for patients who haven’t responded to conventional CRT devices or who can’t have a standard device, but if studies prove it is better then it could be used more widely in future.”
Visit the NHS website for more information about heart failure.