Calcium Mediated Triggered Activity in Cardiac Tissue

It is well known that various cardiac arrhythmias are initiated by an ill-timed excitation that originates from a focal region of the heart. However, up to now, it is not known what governs the timing, location, and morphology of these triggered beats. Recent studies have shown that these focal excitations can be caused by abnormalities in the calcium (Ca) cycling system. However, the cause and effect relationships linking subcellular Ca dynamics and triggered activity in cardiac tissue is not completely understood.