Adrenal Vein Sampling: Tips for Cannulating the Right Adrenal Vein

[Dr. Aparna Baheti]
…Walk me through the Fritz Angle algorithm for how you get into that right adrenal vein.

[Dr. Fritz Angle]
Okay, well, first off, I do always do the left side first because it's easier and the catheter is really stable, but we could talk about that in a minute because you're right. The hard one is, what do you do with the right? I think most experienced operators agree that the C2 is the go-to catheter for this. That works probably 80% of the time.

[Dr. Aparna Baheti]
Just to interrupt you for a second, you're talking about a C2 that has the extra side holes in it, correct?

[Dr. Fritz Angle]
Yeah. Real important point, and we'll put a side hole, and I put that really close to the tip, like 2 mm from the tip because I want that side hole to be literally in that adrenal vein if I can. We'll punch a little side hole used to be the cook side hole punch set, which we used forever, but it is no longer available.

[Dr. Aparna Baheti]
Did it accidentally get tossed and can't reorder it?

[Dr. Fritz Angle]
That's right. You can't reorder it. Re-sterilized the same set of punches, probably for a decade, and finally, they got bent or dull or lost or whatever. But fortunately, you can use a biopsy that's used actually for skin so you can use a dermatologic biopsy, and this device, you get the 0.3-millimeter ones, really small, and you can punch a hole that's just the right size. It does almost always go through both sides, by the way, but don't worry about it. That's fine. We just double-wall it. I usually do it on the bottom of a plastic bowl so I don't ruin my sterile field. If it goes through both sides of the catheter and down into the bowl, that's fine. Just don't use the bowl because it'll leak all over.

[Dr. Aparna Baheti]
You got your catheter, your C2 made, your modified C2, and now how can you get into that right adrenal vein?

[Dr. Fritz Angle]
I've got a good idea from the CAT scan where it is, but the thing Dr. Matsumota taught me is that it's almost always exactly one vertebral body above the right renal vein. First thing I do is drop that catheter in the right renal vein, which is easy to find, and save a levity loop of that. So I've got a mental image of where that is. I'm focusing my attention just about exactly a vertebral body above, straight posterior.

[Dr. Aparna Baheti]
Okay, so you're straight AP with your II, or do you do an obliquity?

[Dr. Fritz Angle]
No, I almost never, that's a good point. I think most of the time, an AP view keeps you oriented. Once you're in it, lateral views or comb beams we can talk about that but just in terms of that catheter work. In fact, I always liken it to sort of mowing the lawn because what I do is I put the thing just about a vertebral body above, or pull it down slowly, puffing contrast, didn't see anything then I'll go back up, turning it a little bit, just going next to the previous path, and do again, and just keep going up and down, up and down, turning it just a few degrees.

So I get the whole back wall of that IVC searched looking for it. It's not something where you see it plop in, and you're like, "Oh, I'm clearly in something let's puff now." It's kind of a deal where you've got to keep puffing contrast. So doing this procedure as someone who has severe renal deficiency can be problematic.

[Dr. Aparna Baheti]
Sure sure. Okay, yeah, that's the part that takes forever is just trying to figure out exactly where that right is.

[Dr. Fritz Angle]
Yes. I'm doing half of vertebral body above and below where I think it is. It keeps the zone I'm mowing very small. Small yard. I got a small yard and if I don't find it, I start looking a little bit left of center and a little bit right of center. Usually, from the CAT scan, I've got an idea if the adrenal vein looks like it's a little bit off to the right or straight in the posterior.

[Dr. Aparna Baheti]
What do you do if you just keep selecting other veins, like hepatic veins, accessory hepatic veins, and you feel like you were talking about where the confluence of that vein is very close to one of the other veins?

[Dr. Fritz Angle]
Yeah, your biggest problem is you keep finding things that you're really confident are hepatic veins, and you can't find the thing that you're looking for and that's a usual frustration. My first piece of advice there is to switch to a different catheter pretty quickly what's that mean? Two minutes of fluoro, probably time to think about a different catheter. A lot of different operators use different catheters, but I find a Mickelson or maybe a Left Gastric or even a Simmons 1 is a good choice and they have varying degrees of pointing down this that you need to change. You try one of those and see and, of course, when you first start, you see how big a cava it is.

Sometimes you can just tell that the C2 is just rattling in that cava it's not even touching the back wall. Then I'll go straight to one of those reverse curved catheters. Sometimes the vein has got a real caudal tilt on it the C2 just slips over it every time and you never see it.

[Dr. Aparna Baheti]
I see. Yeah that's some very good technical points of how long you should flex around with one before switching.

[Dr. Fritz Angle]
Most of the time it's not like, "Oh, I've looked everywhere. It's got to be in a common trunk with this hepatic vein," that's not usually the case. Usually, it's just that you get into some trunk that you can't quite tell if it's just a hepatic vein or it's a hepatic vein and adrenal vein and that's where you got to, I think, break out the cone beam CT. That's so helpful. See, you get into something it's like, "Well, I think it's right where the adrenal should be but, boy, it sure looks like I'm filling in a hepatic vein." Maybe you don't see the collateral's running off into the right or middle hepatic vein. That's a good place to do a cone beam, then you really know you're in the right place or not.

[Dr. Aparna Baheti]
…One of the things you worry about when injecting the adrenal gland is injecting too forcefully or too much. What are your settings for your cone beam that you use to prevent that? Because when you're hand injecting, you can kind of control it but once you have your cone beam in place, what do you do?

[Dr. Fritz Angle]
Yes, super important point. You got to be really gentle, and going all the way back to the beginning of this talk, I always tell patients, complication I worry most about is if you over-inject the healthy adrenal gland, you box them out of getting the operation they need because if you blast, the good gland, give it a venous infarct. How would they know that? Well, unfortunately, you may not find it until post-op when they get adrenal insufficiency. It's just something you want to be really careful about. I don't ever want to inject hard enough that I'm seeing blush. I want to see that sort of ferny pattern, but I don't want to see a blush. So gentle injections.

Now, when it comes to the cone beam, fortunately, almost never have to stand in there and use contrast because I figured out and I'm sorry I can't give credit, but I heard this talk I saw years ago. You put an 0.014 wire through that catheter and push it into the branch you're interested in to be forced on the back then you do just a dry scan. It's really like the 0.014 wire. Is it pointing at the gland or is it pointing at the liver and you got your answer?

[Dr. Aparna Baheti]
Wow, that's amazing.

[Dr. Fritz Angle]
Yeah, because we've got one of these little electronics, safe badges now. We stand in there, you just can't believe how fast you eat the dose up standing in there. No matter how you do it, standing in there for cone beams is a bad idea so don't do it.

[Dr. Aparna Baheti]
Life tips.

[Dr. Fritz Angle]
We used to do this a little years ago, but not anymore. So if I got any questions, I just put a 0.014 wire in there. Actually, that trick often helps with the sampling because the second hardest thing about this procedure, besides selecting the right adrenal vein, is getting the blood out of the adrenal vein.