To contract with a regular beat, the heart follows electrical signals regulated by a natural pacemaker, the sinus node. Yet uncoordinated electrical impulses can arise in the atria, the heart’s upper chambers, causing atrial fibrillation: the atria twitch irregularly, ultimately facilitating the development of blood clots. The troublesome signals often originate around the pulmonary veins, which transport blood from the lungs. Some patients can be treated by blocking these signals with a procedure known as pulmonary vein isolation (PVI), but not all. To determine the likelihood of success, researchers have developed models of the atria and pulmonary veins (pictured). In simulations, varying electrical properties of the tissues (left to right) and the amount of fibrosis (excess connective tissue, increasing from top to bottom) alters the transmission of electrical signals and the response to PVI. Understanding these parameters to build patient-specific models could lead to more effective personalised treatments.
Written by Emmanuelle Briolat
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