Abstract
Disruptions to normal bioelectric rate and rhythm profiles in the heart are cardiac arrhythmias. Their impacts range from minor discomforting symptoms to acute or chronic life-threatening events, with atrial fibrillation increasing the risk of stroke and heart failure, and ventricular arrhythmia associated with sudden cardiac death. To improve mechanistic understandings and advance potential approaches to treatment of arrhythmias, this Interface Focus themed issue on cardiac electrophysiology is a collection of recent studies. They investigate some of the molecular and cellular mechanisms or tissue substrates instigating and maintaining arrhythmia, and discover relevant imaging and signalling biomarkers that assess arrhythmic risks. The studies use imaging, computer simulations, machine learning and both human and animal models in their investigations exploring basic science and strategies for early recognition and improved treatment strategies.