Transseptal left heart catheterization for radiofrequency ablation of accessory pathways

In summary, I think it is important to state that transseptal left heart catheterization is a safe procedure when the operator pays meticulous attention to detail. Potential complications can be avoided if the operator: (1) heparinizes the sheath prior to catheterization, (2) fully heparinizes the patient when the catheter and sheath are across the septum, and (3) remembers that the left atrium in these patients is quite small and can be perforated easily by the tapered tip of the transseptal catheter. Transesophageal cardiac ultrasound makes this latter point very clear to anyone doing this procedure.