Anyone have right heart catheter under Exertion?

I had my ASD/PFO fixed in March 2019. I was able to get off day time oxygen for about 6 months, but still needed it at night. By Oct 2019, I was back on oxygen 24/7 at 2.5L-3L with 4L on exertion.

They have repeated the bubble echo in OCT 2020, and it did not show any leakage. They did a pulmonary cardo function test in Feb 2021. They ruled out traditional pulmonary hypertension in March 2019.

I have been passing out, lack of focus, memory loss, and word retrieval issues. My Syncope episodes are more frequent when not on Sildenafil Citrate. They are triggered normally by walking 3-10 minutes and dryness in the air.

Now they think it is a rare pulmonary hypertension under Exertion only or neurological. They have ordered a right heart catheter under Exertion (while riding a bike).
Just wondering if anyone has had to do this or similar conditions.