Cardiology is the branch of medicine dealing with disorders of the heart and blood vessels. The field is commonly divided in the branches of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology. The normal electrical conduction in the heart allows the impulse that is generated by the sinoatrial node (SA node) of the heart to be propagated to (and stimulate) the myocardium (Cardiac muscle). Signals arising in the SA node stimulate the atria to contract and travel to the AV node. After a delay, the stimulus is conducted through the bundle of His to the Purkinje fibers and the endocardium at the apex of the heart, then finally to the ventricular epicardium. This stimulation of the myocardium allows efficient contraction of the heart, thereby allowing blood to be pumped throughout the body.

Cardiac arrhythmia is the conditions in which there is abnormal electrical activity in the heart. Some arrhythmias are life-threatening medical emergencies that can result in cardiac arrest and sudden death. In electrocardiology research, action potential propagation on heart surface has been used as a tool to study the source of cardiac arrhythmia, re-entry dystrhythmias, atrial flutter and artrial fibrillation.



Electrocardiac mapping system:
Our recent challenging project was to detect the epicardial action potential propagation delay (called 'activation time') in real-time mode in University Hospital in Cleveland of Case Western Reserve University. In this system, data acquisition from 512 electrodes and activation-time mapping in right atrium was performed in real-time, which provide instantaneous feedback of experimental condition and the effect of interventions such as radiofrequency (RF) ablation and drugs. This system can provide automatic detection of biopolar/unipolar action potential propagation and dominant frequencies in epicardial surface in right atrium. This mapping system (as a prototype) was already used successfully to acquire human data in the University Hospital in Cleveland. It will be applied to the electrophysiology (EP) study in human at the Cleveland Clinic.