Recently, a new generation of transesophageal echocardiography (TEE) probes with a novel matrix array technique was introduced, allowing three-dimensional (3D) presentation of cardiac structures in real-time. This article aims to describe our first experiences with this new technique in the guidance of percutaneous cardiac interventions in the catheter laboratory. We used a matrix array 3D TEE probe connected to a 3D-capable echocardiographic system. The 3D TEE system provides exact imaging of the pathomorphology of cardiac structures as well as intracardiac catheters and devices in real-time. We applied this innovative technique to monitor percutaneous cardiac interventions in the catheter laboratory, such as atrial septal defect (ASD) or patent foramen ovale (PFO) closures, revalving procedures such as percutaneous transvenous mitral valve annuloplasty (PTMA), aortic valve replacements, and electrophysiological procedures. Our findings demonstrate that real-time 3D TEE provides a novel imaging technique to guide interventions in the catheter laboratory, providing fast and complete information about the underlying pathomorphology, improving spatial orientation, and additionally monitoring online the procedure without loss of image quality. These benefits may accelerate the learning curve and improve confidence of the interventional cardiologist in order to increase safety, accuracy, and efficacy of interventional cardiac procedures.