Southampton heart experts first in the UK to implant new leadless pacemaker defibrillator system

Heart experts at University Hospital Southampton (UHS) are the first in the UK to implant a new leadless pacemaker defibrillator system to treat patients at risk of sudden cardiac arrest.

The procedure, which is part of a global clinical trial, involves having two devices fitted – a subcutaneous implantable cardioverter-defibrillator (S-ICD) and the new leadless pacemaker known as EMPOWER.

The combined devices, known as the modular Cardiac Rhythm Management (mCRM) Therapy System work together to prevent sudden cardiac arrest if a life-threatening abnormal heart rhythm (arrhythmia) is detected.

Pacemakers provide electrical stimulation to regulate a patient’s heartbeat while an S-ICD is implanted to constantly monitor the patient’s heart rhythm.

The system uses pacing in the first instance via a new leadless pacemaker which sends painless electrical signals to correct the heart of the abnormal rhythm.

It will then use shock therapy from the S-ICD only if required as this can be more painful and traumatic for patients.

Certain types of arrhythmia occur in people with severe heart conditions and can cause sudden cardiac death.

In the UK there are over 30,000 out-of-hospital cardiac arrests (OHCA) a year where emergency medical services attempt to resuscitate the patient, however, the survival rate is low – just 1 in 10 people in the UK survive an OHCA.

Annually, UHS implants more than 300 ICDs and follows up almost five thousand patients who have previously had the devices fitted.

Traditionally pacemakers are inserted under the skin via an incision in the chest and are connected to the heart via a lead threaded through the blood vessels.

However, these can be complicated with infections, obstruction of blood vessels and occasionally faults in the leads.

With this new procedure, the leadless device is placed inside the wall of the heart via a small tube passed up through a blood vessel in the groin which takes just one hour using keyhole surgery.

Previously, patients who have received an S-ICD alone have not had the capability to receive pacing for slow heart rhythms or termination of sudden cardiac arrest due to an elevated heart rate.

Patients who require a defibrillator and have evidence of an abnormal heart rhythm may be offered the new EMPOWER implant as part of the clinical trial at UHS, where clinicians have recently implanted the third device.

Professor Paul Roberts, consultant cardiologist at UHS, led the medical team and has extensive experience in implanting leadless devices. He was also involved in establishing the training course for this procedure.

“This first in the UK implant of a leadless pacemaker combined with a defibrillator that is able to deliver pacing to stop life-threatening heart rhythms prior to the need for shock treatment represents a major advance in treatment for patients,” he said.

“Previously, patients implanted with only an S-ICD will not have had the advantage of pacing or may have been offered a replacement transvenous device which can pace first and then shock but will have carried the associated risks of leads in the heart – movement, fracture, infection – as well as more invasive surgery.

“The mCRM Therapy System will benefit a much larger patient population and enable the majority of lethal arrhythmias to be painlessly terminated without long-term risks associated with both shocks and conventional pacemakers.”

David Mills, 56, a retired policeman from Southampton is the first patient in the UK to undergo this procedure.

He said: “I feel very honoured to be part of this clinical trial and to be the first person in the UK to have the device implanted as it has given me the confidence to carry on a normal life.

“I hope the results of this trial will help to provide important insights so that soon more people can benefit.

“The clinical team at UHS have been very reassuring and approachable throughout, responding to any questions I may have had along the way and supporting me so well – I can’t thank them enough for what they have done.”

The clinical trial is sponsored by Boston Scientific, manufacturer of the modular system, and will enrol up to 300 patients across 50 centres in Europe, the US and Canada including patients who require a new ICD or who already have a subcutaneous-ICD system implanted.

The trial will evaluate the safety, performance and effectiveness of the modular cardiac rhythm management system.

EMPOWER is an investigational device and not yet available for sale in Europe.