There are 22 million people in the world suffering from heart failure. It occurs after heart muscle damage from a heart attack, viral infection or several other causes. Patients complain about shortness of breath, swelling of legs and general lack of energy. The heart muscle is weakened and the heart enlarges, pumping less effectively.

Cardiac Resynchronisation Therapy (CRT) is a form of pacing therapy where both the lower chambers of the heart (namely the left and right ventricles) are paced simultaneously. This highly effective form of therapy helps improve heart failure symptoms and can be used to delay and even replace cardia transplantation in some patients.

It can only be performed in selected patients as only 60% of patients benefit from this therapy.

The CRT implant is more complex than a pacemaker. A lead is first placed in the right ventricle. Then a specialized lead is placed in a vein called the coronary sinus, over the left ventricle. Finally, an atrial lead is inserted.