New ICD performs well in international study

11th May 2015

An internal defibrillator that does not use leads into the heart has shown itself to perform similarly to more traditional implantable cardioverter defibrillators (ICDs), says a large new study.

There has been limited data on the long-term performance of subcutaneous defibrillators (S–ICDs). Now the first international study of patients with S–ICDs shows “appropriate system performance with clinical event rates and inappropriate shock rates comparable with those reported for conventional ICDs”.

The data has come from a multi-centre registry looking at results in patients who have received the devices since June 2009.

S-ICDs are given to those who have had a cardiac arrest or doctors think are at risk of having one. They can detect a life-threatening heart rhythm and give a shock to restore your normal heart rhythm.

But unlike traditional ICDs they cannot also pace the heart. So they are not suitable for people who have heart failure or need a pacemaker. Because the leads are outside the heart, complications that can occur with ICD leads are reduced.

The EFFORTLESS S-ICD collected five year data, including quality of life information.

It covered 472 patients aged from nine to 88. They had a mean ejection fraction of 42 per cent (in a normal heart this figure is around 55-60 per cent). Seven in ten were men.

Centres taking part in the study included the Heart Hospital in London, Kings College London plus institutions in Holland, Germany, Denmark, the Czech Republic and New Zealand.