Abstract
Catheter-based ultrasonography is a widely used tool in cardiac electrophysiology practice, and intracardiac echocardiography is supplanting other forms of imaging to become the dominant imaging modality. Given advances in pericardial access, intrapericardial echocardiography can be performed using ultrasound catheters as well. Intrapericardial echocardiography and echocardiography from the coronary sinus, also an epicardial structure, allows interventionalists to obtain unique views from virtually any vantage point, compared with other forms of echocardiography. Both intrapericardial echocardiography and coronary sinus echocardiography are safe and important alternatives that can be used during complex procedures in the electrophysiology laboratory.