Hi
This is a typical example,

Hi

This is a typical example, where right systolic failure causes a drop in pressure gradient. This stenosis is certainly severe, but myocardial failure leads to a drop in systolic RV pressure. The severe TI hiere could as well be caused by tricuspid dysplasia – difficult to say here. Also, severe Ti leads to a drop in RV forward output and consequenty a loss in pressure gradient.

I cannot say anything about the coronaries here. Based on my experience with cardiac CT scans (<4 years, more than 100 cases), there are many different anomalies, with not all of them having been published so far. You can of course look out for coronary ostia on short axis views but even the fact that there are 2 of them does not rule out coronary anomaly!

Ballon valvuloplasty will certainly not lead to normalization of the RV. Many of these patients have a poor prognosis even with BVP once they are in failure like this one. Of course it can be attempted. If the dog has a coronary which encircles the PV, the effect of BVP will be low. This has to be ruled out using angio or CT.

Surgery can also be considered provided that the coronaries are ok. Surgery usually leads to a very good effect on PGs (they drop to normal or almost normal). Yet, there are only few data out and experience is limited. Luckily, we have not lost a case during surgery or the recovery time so far.

Re Butorphanol. The drop in PG after Butorphanol has been shown to be very limited.

Peter