Argon Option ELITE IVC Filter Placement Technique

[Michael Barraza]
I was hoping you could just start by telling me a little bit about your IVC filter placement and retrieval programs at Columbia.

[David Mobley]
It's pretty standard and it follows the recommendations by the Society of Interventional Radiology guidelines. It's put in when indicated and there are several indications for placement of a filter. We try to remove them as soon as possible when it's indicated and when the patients are able to have them removed.

[Michael Barraza]
Okay, and so I've read a poster you guys did on a placing the Option filter over the wire. Could you tell me a little bit about that?

[David Mobley]
Sure. For years we've been placing filters in the IVC and we've been placing them jugular and femoral like the rest of the country. The Argon Rep had come to me and said, ”Listen, we've got this filter which we had been using for awhile." And he said, "This filter is the only one that has a hole right through the middle.” He had this idea of placing it over the wire with the wire extended all the way into: either the femoral up into the SVC, or jugular down into the Iliac vein, and deploying it with that wire extended all the way distally.

There has been some contention with the placing and tilting of filters within the IVC. It's believed that tilting of the filter makes it less effective in its protection from DVTs creating pulmonary embolisms. Also, it's believed that the increased tilting makes it more difficult to remove depending on how long it's been in. We had placed many of our filters through jugular and transfemoral access points. When the rep came to me and made this suggestion, I listened to him and talked to him about the technique.

I tried it a few times and it worked out very nicely and I said, “alright, well let's take a look at this.” So we did. I believe it was around 39 patients and we looked retrospectively at those patients, and the 40 patients prior to that, that had been performed with transfemoral access. We looked to see if there was a difference in tilting and it showed a statistically significant difference in tilting between the filters placed over the wire and not over the wire.

[David Mobley]
The Option filter comes with a deployment sheath, a dilator, and a pusher that has a wire extending about 10 centimeters beyond the end of it. The wire already goes through the end of the filter’s end hole, so you already have a wire going through it. We get femoral vein access with ultrasound guidance with the Micropuncture set, and we put in a Bentson wire. Up and over the Bentson wire we place the Argon Sheath. We then do an IVC-gram, so that we see where our renal veins are, and confirm IVC placement.

After that, we put the Bentson wire back into the sheath with the dilator and we get the exchange length Bentson up into the SVC. We then move our sheath up into the appropriate level at the level of the renal veins while leaving SVC access with the exchange length Bentson. We remove the dilator from the sheath with the sheath in the proper positioning. That dilator then comes all the way off the wire. We then place the filter on the wire, being very careful to gently put the wire through the end of the filter deployer. You do this while holding your finger at the end filter deployer, so that when you push that wire through gently, it doesn't actually push the filter out the end of the deployer. Once you do that, you grab the wire, you put your fingernail on the end of that deployer, and you bring the deployer all the way up to the sheath. You place the deployer into the sheath until it locks. And instead of using the pusher, you actually use the original dilator that you put in the sheath with, and you run that over the wire and you use that as the pusher.

The original pusher has a wire coming out the distal end and it has a plastic sheath used as a pusher. What we're using instead of one piece of equipment is two. We're using an exchange length Bentson and we're using the original dilator as the pusher. We maintain back tension on the Bentson wire making sure it's still in the SVC, and that's a little bit of the added time, just making sure that wire hasn't moved anywhere. Once we confirm that that wire is still in the SVC, we look back down into the abdomen, we use the pusher to advance the filter up into the deployment area, and we maintain forward pressure on the dilator and the wire. We then unsheath the filter in the position that we originally wanted it to be.

[Michael Barraza]
Got it. So it's just the wire, it's like a stabilizer, that maintains the straight position?

[David Mobley]
Exactly. The dilator that we're using as a pusher is keeping it in the position as you're unsheathing it and the wire's keeping it stabilized in the longitudinal frame compared to the IVC.