What is/are your preferred technique(s) for obtaining LV-Ao pressure gradients in the cath lab?

Two other ways to do this I learned while the Langston Cather was on back order to use a 6F 75 or 85 cm R2P sheath parked in the ascending aorta and a 4F pigtail in the LV. With two transducers (on off the side of R2P and one on pigtail) and a 2F difference in size of catheters, you get nice fidelity. One alternative to this is to use a swan with a balloon up in the LV and transduce from the distal and proximal ports. Many ways to skin a cat, they say.

With the Langston catheters unavailable, an R2P sheath in the aortic arch, and 4Fr pigtail in LV is a good option. A 5fr guide catheter and a 0.014” iFr/rFr/dPr wire in the LV is an even better option, with more accurate trans AV gradients, as the 0.014” wire occupies a tiny area in the AV orifice.