What is a potential consequence of performing a transseptal puncture through a patent foramen ovale (PFO)?

The potential consequence of performing a transseptal puncture through a patent foramen ovale (PFO) is indeed the unstable positioning of the catheter. When a PFO is present, the anatomical variability can make it challenging to achieve stable access to the left atrium. The PFO can allow for unwanted movement or shifting of the catheter, which may complicate the procedure and lead to difficulties in navigating and placing the device accurately. This instability can increase the risk of complications during the procedure, as it may prevent the operator from maintaining effective control and positioning of the catheter.

In contrast, other consequences, such as increased stability of the catheter, would not occur in the presence of a PFO. Additionally, the success of the procedure is not guaranteed merely because a transseptal puncture is performed, especially if stability and control are compromised. Finally, it's important to recognize that the presence of a PFO does have an impact on procedure outcomes, contradicting the idea that it would have no influence.