LAAEI

So a couple days ago I somehow had full access to the just released AHA journal article authored by Natale, Dibiase and Romero detailing and supporting the effect of electrically isolating the LAA. The full article is now behind a paywall, but there was a discussion that really caught my eye, and I'm hoping someone else may have read it and be able to explain it a little better for me. The article is posted here.

In particular, there was a discussion regarding continuing AC after having your LAAEI. The statement was that when blood flow in/out of the LAA was below a certain threshold (<=40 ml?), and the "A wave" was not discernible, the patient would need to remain on AC for life. The exception being if their LAA was occluded in a pericardial or endocardial way (Lariat or Watchman or similar). Many of us that have either an EI LAA and/or occluded LAA are aware of this information. My interpretation here is that with low flow and poor to non-existent electrical function (?) of the LAA, it is concluded that the LAA is "dead", and thus a prime location for the formation of thrombus and really bad things happening to you. Hence the advantage of the occluded LAA.

Now the part of the article that stopped me in my tracks, and I wasn't aware of, was that should your EI LAA show excellent blood flow and a "healthy" A wave, it is concluded that perhaps your LAA isn't EI after all, and functioning at a level (probably in conjunction with a chicken wing LAA morphology?) that would allow cessation of AC. Dr. Natale did an EI on my LAA, and after the follow-up TEE at 6 months my flow was at .45 (ml?), and the A wave was, I believe, questionable. I have since had the Watchman FLX placed, and I have been, I believe, arrhythmia-free since the Natale ablation (my 2nd, 1st by him). After the 6 month TEE I was told I could go off AC if I desired, and I chose to go on a reduced dose of Eliquis. I'm now only on dual anti-platelet strategy until February (as part of the Pinnacle FLX clinical trial).

So here's where I'm going, and where I'm lost. Is it safe to say my EI LAA reconnected because the flow is better than the minimum Natale looks for in the post ablation TEE? As I recall, the journal article says just that, that it is assumed the LAA is NOT isolated. And is it possible the afib/flutter circuit was killed while the LAA retained enough function to maintain flow? (It's also important to note that LAA morphology plays a huge role in flow and potential thrombus formation.) If that is the case, does this mean that there is a much higher probability of afib or flutter returning - originating from my now occluded LAA? I know I was told an LAA that has been occluded via a Watchman can still be ablated again if necessary. I suspect the number of people who have had LAA originated afib/flutter that also have a Watchman or similar AND undergone an ablation to silence it are a very, very small population. I'm afraid to ask what the potential risks are for ablating an LAA with an occlusion device, or are they really similar to any other "standard" Natale ablation that involves EI the LAA. Hopefully I'm concerned about nothing because, as I mentioned, I've been in NSR for 18 months now. It's comforting knowing that while some of us are living on the cutting edge of afib technology and treatment, it's reinforced by the skill and instinct of Dr. Natale and the best-in-class folks at TCAI and St. David's.

I'd be curious if anyone has any thoughts - thanks.



Edited 1 time(s). Last edit at 11/06/2018 01:02PM by AB Page.

No it is NOT automatically and inherently safe to say that just because your Electrically isolated LAA that means you can safely stop all OAC! The >40mm/sec metric refers to the LAA emptying velocity and it is only ONE of THREE metrics you must pass with flying colors to only 'potentially' earn the right to stop OAC therapy for good.

Now in your case Andy, since you made the smart move to include a Watchman FLX LAA Occlusion procedure (and with the good fortune to be enrolled in the Watchman FLX trial) you should easily be able to DC the OAC after the study phase of the trial is over.

And also be careful in over-or-under-interpreting study comments from a layman's perspective. Its easy to read into such comments that the authors may not have meant to convey in the way a layman might have assumed they meant.

What I dont want people reading the above synopsis of the excellent new LAAEI article by Drs. Di-Biase, Romero and Natale et. al, in Circulation I believe, to assume that simply passing the LAA emptying velocity test is enough to qualify you for stopping a blood thinner and even avoiding an LAA Occlusion device based solely on passing that one metric >40mm/sec to 45mm/sec minumum LAA emptying velocity.

You also have to have a consistently robust beat-by-beat Doppler A-Wave peak into the Mitral Inflow .... AND you must not show any at all 'Smoke' or SEC ( Spontaneous Echo Contrast) on a TEE test. All three tests must be passed before anyone gets a free ride without a blood thinner.

Check with Natale at the end of your Watchman-FLX trial for specific instructions on how he wants you to proceed, I'll fill in more nuances on this issue tomorrow but it's late night here and my eyes are closing after the long day of travel ..

Cheers!
Shannon



Edited 1 time(s). Last edit at 11/07/2018 01:56AM by Shannon.

Shannon,

Thank you for your informative and thoughtful reply during a difficult time.

I am of course a layman in understanding medical procedures etc. I never meant to pass on as fact my incomplete understanding of the circumstances under which someone can stop AC. What I was trying to say, and did it poorly, is if my LAA was a source of afib or flutter and was also electrically isolated, does the article say that with the flow numbers I have it is assumed to be reconnected? And if so, why have I not gone back into arrhythmia? Is that perhaps just an unknown or mystery at this time? Or maybe the bad pathways were burned and functional pathways left intact? As I recall, the article might have stated that the tissue around a chicken wing LAA, at the ostium, is thicker than other morphologies. Could that make it at the same time "easier" or safer to occlude while at the same time make it more challenging to fully isolate? Thanks for bearing with me. I'm obviously not a medical professional, but I try to understand the basics of this. And I know a little knowledge is dangerous too No matter what, the NSR I have enjoyed these past 18 months have enabled me to live life, and for that I am always grateful - to you and Dr. Natale and all the wonderful folks in Austin.

Andy

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AB Page
What I was trying to say, and did it poorly, is if my LAA was a source of afib or flutter and was also electrically isolated, does the article say that with the flow numbers I have it is assumed to be reconnected?

No, it's not safe to say that. Natale isolates the LAA only to the degree necessary to stop the arrhythmia. So one patient might have more LAA pumping ability after the procedure than another. You had a better flow velocity than I did, so that most likely means Natale had to isolate my LAA more completely than yours in order to stop the arrhythmia. Some of it could also just be simple individual differences. I don't think you're in any danger of your LAA reconnecting and afib returning because of that.

Could I piggy-back here with a related question? Would having a Watchman (FLX) in place complicate matters if one subsequently became in need of an additional ablation procedure? Or would it make not much difference?

Thanks!

--Lance

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Carey

What I was trying to say, and did it poorly, is if my LAA was a source of afib or flutter and was also electrically isolated, does the article say that with the flow numbers I have it is assumed to be reconnected?

No, it's not safe to say that. Natale isolates the LAA only to the degree necessary to stop the arrhythmia. So one patient might have more LAA pumping ability after the procedure than another. You had a better flow velocity than I did, so that most likely means Natale had to isolate my LAA more completely than yours in order to stop the arrhythmia. Some of it could also just be simple individual differences. I don't think you're in any danger of your LAA reconnecting and afib returning because of that.

Dr Natale ablated my LAA twice during my procedure as affib initiated at some point after his initial visit to the area. I'm interested to see how my LAA function is sometime early next year.

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Carey
No, it's not safe to say that. Natale isolates the LAA only to the degree necessary to stop the arrhythmia. So one patient might have more LAA pumping ability after the procedure than another. You had a better flow velocity than I did, so that most likely means Natale had to isolate my LAA more completely than yours in order to stop the arrhythmia. Some of it could also just be simple individual differences. I don't think you're in any danger of your LAA reconnecting and afib returning because of that.

Interesting. I hadn't really given it much thought until I read the article. Of course I just assumed he burned the bejesus out of it to prevent any and all activity. I think I was applying a generally accepted, everyday definition of the word isolate to a highly specific medical procedure. Yet another reason why someone like me probably shouldn't try to understand a medical/scientific journal article. I didn't think I was in danger of reconnection, but thought it worth asking after reading the article. Thanks for the clarification Carey.

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ln108
Could I piggy-back here with a related question? Would having a Watchman (FLX) in place complicate matters if one subsequently became in need of an additional ablation procedure? Or would it make not much difference?

I asked Natale that specific question before my ablation and he said he has to be more careful when working in that area, but it doesn't preclude another ablation at all.

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Carey
I asked Natale that specific question before my ablation and he said he has to be more careful when working in that area, but it doesn't preclude another ablation at all.

Interesting. Thanks, Carey!

--Lance