Grant: Project Grant

Background: The atria are the two upper chambers of the heart. Irregular heartbeat initiated in the atria can occur in 20-40% of patients after receiving heart surgeries. This abnormal heartbeat can cause various adverse effects including death. It is imperative to find methods to prevent and treat such irregular heartbeats. Normally the heartbeat is controlled by electrical signals generated by specialized proteins called ion channels. There is a type of ion channel that is specifically present in the atria, and is involved in the development and treatment of atrial fibrillation. Research aims: This project aims to explore the possible causes of irregular heartbeat initiated in the atria after cardiac surgery and explore novel ways to prevent and treat it by targeting a type of ion channels localized in the atria. Description of the project: Heart surgeries are associated with inflammation in the cut regions of the heart. During inflammation, white blood cells release some special proteins called enzymes which can cut and breakdown other proteins. We believe that i) some released enzymes may break up some electric generating proteins (ion channels), thus altering electrical signals and causing irregular rhythm in atria. ii) drugs that inhibit these enzymes can prevent heart surgery-associated, atria-initiated irregular heartbeat. We will examine our theories in ion channel proteins grown in cultured cells and in myocytes from animal and human atria. We will use animals (rabbits) as well as collect information from patients receiving heart surgery at Kingston General Hospital to correlate the incidence of above-mentioned irregular heartbeat with the levels of the inflammation-associated enzymes. Significance: Irregular heartbeat initiated in atria is the most common problem in patients after heart surgery. This project tackles the issue based on a completely new concept with an aim to find drugs that can prevent and treat irregular heartbeats after surgery.