Many noninvasive and invasive tests can delineate cardiac structure and function (see table ). Also, treatments can be administered during certain invasive diagnostic tests (eg, percutaneous coronary intervention during cardiac catheterization Cardiac Catheterization Cardiac catheterization is the passage of a catheter through peripheral arteries or veins into cardiac chambers, the pulmonary artery, and coronary arteries and veins. Cardiac catheterization... read more , radiofrequency ablation Ablation for Cardiac Arrhythmia The need for treatment of arrhythmias depends on the symptoms and the seriousness of the arrhythmia. Treatment is directed at causes. If necessary, direct antiarrhythmic therapy, including antiarrhythmic... read more during electrophysiologic testing Electrophysiologic Studies (EPS) In electrophysiologic studies (EPS), recording and stimulating electrodes are inserted into all 4 cardiac chambers via right- or left-sided cardiac catheterization. Atria are paced from the... read more ).