Researchers find current drug can treat rare heart disorder

New research has found that the answer to treating a rare inherited heart disorder could lie with a drug already on the market.

Associate Professor Derek Laver from the University of Newcastle and international colleagues have found that Flecainide – a drug used to treat heart arrhythmias – could also be used to treat Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT).

CVPT is a heart arrhythmia induced by emotional stress or exercise. It is estimated to cause 15 per cent of all unexplained sudden cardiac deaths in people under the age of 30.

Associate Professor Laver said CPVT was caused by too much calcium being released from calcium stores within the heart cells.

"Correct calcium flow within the heart cells is essential for the heart to function properly," he explained. "Calcium is released from the stores into the heart cells through specific channels and we have found that Flecainide reduces the ability of these channels to release calcium, thereby directly counteracting the cause of CPVT."

Currently, beta-blockers are used to treat CPVT but 37 per cent of patients are unresponsive and 24 per cent suffer sudden cardiac death within 10 years of beginning treatment.

Implantable defibrillators are used to prevent sudden death but these cause painful electric shocks that can trigger further stress-induced arrhythmias.

"Current treatments are largely ineffective and we need new and more effective anti-arrhythmic drugs," Associate Professor Laver said.

"We have now discovered something close to an ideal drug for this rare arrhythmia disorder."

The research is published in the latest edition of the Nature Medicine journal. It was funded by several research agencies including the University of Newcastle through the Gladys M. Brawn Memorial Fellowship; and the NSW government via an infrastructure grant to the Hunter Medical Research Institute (HMRI).

Associate Professor Laver works in collaboration with HMRI's Cardiovascular Health Research Program. HMRI is a partnership between the University of Newcastle, Hunter New England Health and the community.