Anatomic insights for catheter ablation of ventricular tachycardia.

Safe maneuvering of catheters in and around the ventricles, and ablations for ventricular tachycardia, require knowledge of the anatomy of the cardiac and extracardiac structures. This review emphasises the three-dimensional spatial relationships between the right and left ventricles and highlights the important extracardiac structures in the vicinity of the ventricles. The spatial relationships between the right and left ventricles are intricate owing to the curvature of the ventricular septum. The crossover relationship between the right and left ventricular outflow tracts and different planes and angulations between the aortic and the pulmonary valves is particularly relevant to intervening in the ventricular outlets. Importantly, the central location of the aortic valve in the heart puts it in the vicinity of all four cardiac chambers, both for access and for reducing risk of damage to vital structures such as the atrioventricular conduction bundle. The locations of the cardiac chambers are not as simple as implied by the commonly used terms 'right heart' and 'left heart'.