The
Cardiomyopathy
Association

A procedure that uses electrical energy to destroy heart tissue has shown some promise in the treatment of children who have hypertrophic cardiomyopathy (HCM) with obstruction.

The procedure, called radio frequency catheter ablation, is more commonly used to destroy - or ablate - tissues in the heart causing rhythm disturbances.

But research at two centres has shown it may also help children who have HCM with thickened heart muscle that obstructs blood flowing out of their hearts.

The procedure, performed via catheters inserted into the groin, demonstrated significant improvement in some children with HCM, said a new report in the Journal of the American College of Cardiology.

Those with HCM and obstruction can suffer from tiredness, breathlessness, chest pain, exercise related fainting and occasionally sudden death.

Adults can be offered a myectomy, open heart surgery that involves removing heart muscle that is causing the obstruction, or an alcohol septal ablation, when alcohol is injected in the heart muscle to try to kill off the area causing the obstruction.

The second technique is not feasible for children, so historically a myectomy has been the only option, said Dr Joseph de Giovanni, from Birmingham Children's Hospital.

But from June 1999 to January 2011, the researchers enrolled 33 HCM patients with a mean age of 11 in trials of radio frequency ablation at Birmingham and in Cologne, Germany.

The young patients had not responded to drug treatments and were offered the radio frequency ablation as an alternative to a myectomy.

In all, 32 underwent the alternative therapy. All but one patient reported symptomatic improvement in follow up over four years.

The researchers reported four children underwent a second catheter ablation procedure between six and 64 months after their initial ablation, although all had demonstrated a good acute response to the initial procedure.

One child underwent a myectomy when there was no change in outflow from the heart after catheter ablation.

One patient died in her sleep two and a half years after the ablation procedure. It was believed she died from heart rhythm problems.

Dr de Giovanni’s team said that if the safety and efficacy of radio frequency catheter ablation could be established in larger studies, it might result in the reduction of children needing a myectomy.