[HSF] Routine closure of the left atrial appendage?

[erdinç naseri]

Don,
I agree with you and Ben that most of the cases of POAF are reversible and benign but when not ,you end up with a patient who has been cured of his-her coronary stenoses but can' t either walk or talk or see"or....Sad end and I have experienced it in a young postCABG patient.
erdinc> From: donross at bigpond.com> Subject: Re: [HSF] Routine closure of the left atrial appendage?> Date: Fri, 20 Jul 2007 12:11:00 +1000> To: OpenHeart-L at lists.hsforum.com> CC: > > Ben,> Lovely stuff.> I know this exercise, like so many, involves hypotheses which will > never be proven by the iron pyrites standards of EBM.> I agree that transient post op AF is common and almost always benign > and I rarely expose these patients to anticoagulaton knowing that it > is not benign (EBM proven)> Then I have a young man who had transient AF, who went home in sinus > rhythm get big embolic (in AF ) stroke 10 days later.> I know it is the only one I am aware of in 27 years of practice but > because I am staring at the LA appendage contemptuously flapping at > me every day I decide to take revenge.> Such passion is rarely rewarded in science.> I tried to find a safe, reliable and cheap LAA decapitator but failed.> Thus, at peace with myself once more, I continue with my other non > EBM provable passion of anaortic cabg which has yet to fail.> Don> On 20/07/2007, at 7:41 AM, Ben Bidstrup wrote:> > > The aetiology of postoperative stroke is far from well defined. How > > many are embolic from AF is even less well understood.> > What do we know?> > AF often starts at day 2-5, is often self limiting. Rate control is > > as effective as use of more potent anti-arrhythmic agents (eg > > digoxin vs amiodarone) and SR ensues after a few days.> > It usually needs 48 hours of AF before the risk of emboli arises. > > i.e. clot can be seen in the LAA.> > Post cardiac surgery and I include OPCAB here, there are changes in > > the thrombotic potential - alterations in prothrombosis, in > > fibrinolysis such that DVT is increased in some series of OPCABs or > > at least in anecdotal reports (I have seen what i believe to be a > > higher than usual rate after OPCAB but that is relying on memory > > rather than a strict , critical review of my own data.)> > These changes act in opposite ways - pro and anti thrombotic.> > Patients with CAD have atheroma elsewhere and may have unstable > > plaque in the cerebral circulation or the supplying vessels.> > The possible mechanisms for clot formation in the arterial side is > > different to low flow situations. High shear vs low shear, platelet > > aggregation vs thrombus formation.> > out of the Hammersmith came multiple studies, Chris Blauth was the > > researcher who first looked at this (under Ken Taylor's watchful > > and inquiring eyes). He used intra-operative fluoroscein > > angiography to show multiple small filling defects in the retinal > > circulation, the window on the brain. In parallel animal studies, > > these were seen to be platelets - probably platelet white cell > > aggregates as these occur in a pro- inflammatory situation like CBP.> >> > There is then a milieu for later problems as noted above.> > Where does AF and LAA embolism fit into this picture.> > In my opinion, not enough to justify in the majority of cases > > ligation by whatever method the LAA. Far less to support the use of > > some expensive device that will achieve what a 20c piece of 0 black > > silk. That includes a linear stapler.> > Is ligation likely to be prophylactic against LAA embolism.> > Now in this ear of EBM, let us look at the prospective study to > > answer the question.> > (Don, please read on - this is science)> > 1. RCT: ligation vs no ligation> > 2. Detection of LAA thrombus. Needs daily TOE (TEE to you Yanks) - > > cost ? tolerability?> > 3. How to detect embolism - diffusion weighted MRI to exclude > > watershed injury vs other sources. Cost? availability? How frequent?> > 4. Now determine sample size. Rate of af varies enormously - rate > > of stroke of cerebral injury in AF patients might be say 4% in 25% > > of CABG so 1% of CABG. But AF alone is not an endpoint nor is > > stroke - we want to see if we have stopped LAA thrombus. What is > > the rate of this without an intervention - need a pilot study HM > > patients in that say 2-300.> > 5. So we have the bare bones to do this - write protocol - get > > funding. Cost Millions $$$$$$. Will the AF device company fund that > > - you tell me bit I think we all know the likely answer to that. > > NIH ? HM worthy proposals get funded by them in cardiac surgery.> > 6. We start and get a few problems with bleeding and maybe a few > > deaths. These get reviewed by the safety committee. Hard to blind > > this truly, so it will be easy for them to determine the treatment > > group. Study is stopped on patient safety grounds.> > 7. But I have not seen any problems with LAA ligation/stapling/ use > > of you-beaut device A. Well you haven't done it enough. And you are > > not doing all of them. There will be many hands of varying > > experience in this multi centre study (possibly world wide).> >> > Now many will say this nihilism. Yes maybe and if we think this way > > all the time, we will never see an RCT get to fruition. Not all are > > fraught with these issues, but I am trying to be realistic. The > > value of an 87 patient study with no Holter monitoring and > > selective use of TOE or MRI is virtually zip. It is likely to get > > published, many of us do not have the heart to outright reject > > these papers and many will end up in second tier journals. If they > > come from a prestigious institution, may get into a first tier.> > Will they answer the question?> > You tell me.> >> > Glossary:> > you-beaut - an Australian expression for bonzer or rather good or > > super> > Nihilism: (from the Latin nihil, nothing) is a philosophical > > position which argues that the world, especially past and current > > human existence, is without objective meaning, purpose, > > comprehensible truth, or essential value. (from Wikipedia). As John > > Pym pointed out so eloquently (quoting from Monty Python - > > Nietzsche and Heidegger have both opined on this)> > RCT: randomised controlled trial> > LAA: left atrial appendage> > MRI: magnetic resonance imaging> > CBP: cardiopulmonary bypas. (Still used by about 90% of surgeons > > for CABG)> >> >> >> >> >> >> >> >> Ani,> >> 1.LAA is the site of formation of thrombus nidus in patients with > >> LA clots .This is the source of cardiac emboli in patients with > >> otherwise normal LV endocardium and cavity.If ligated free of > >> complication there will be a prophylaxy against this type of CVA.I > >> ligate it externally with silk suture and to date there hasn't be > >> a catastrophic bleeding( hope this will be so forever)> >> 2.AF surgery is not in much use here so no anecdotal catastrophic > >> events known by me.> >> 3.Though there are not much medical suits here ,still we get > >> written consent of the patient for all the procedures.> >> 4.No statistically valuable data .> >> erdinc> From: anianyanwu at hotmail.com> To: openheart- > >> l at lists.hsforum.com> Subject: RE: [HSF] Routine closure of the > >> left atrial appendage?> Date: Thu, 19 Jul 2007 10:44:15 +0000> > > >> But Erdinc,> > What is the evidence (provide references if you) > >> can that> > 1. LAA clot is the cause of embolic strokes seen with > >> AF> 2. Ligation of this structure eliminates or reduces the risk.> > >> 3. A patent LA appendage is a cause of stroke after cardiac > >> surgery> 4. Obliteration of the LAA reduces stroke risk after > >> cardiac surgery> 5. Obliteration of the LAA is not without risk.> > >> 6. An LAA which has been patent and clot free for decades (even in > >> a patient with long history of AF) will suddenly develop clot > >> within because you did a heart operation.> > While I await the > >> data, In response to your statement that you would rather have a > >> patient neurologically intact, I would rather have one alive with > >> a theoretical risk of embolic stroke than one who haemorrhages to > >> death from this easy (or timorous!)> >> inconsequential procedure as many might believe. BTW ask around > >> about deaths after mini-invasive AF surgery and you will find > >> stories of disasters from interfering with this structure. A rep > >> told me of three such deaths in young patients.> > Again that we > >> can cut bits and pieces out the body, even if without risk for the > >> extraordinarily skilled surgeons amongst us, doesn't mean we > >> should - these bits and pieces belong to a human being's body and > >> we should respect that. BTW (and this goes to Hal's land of > >> medicine by lawyers) if a patient sued you for wrongfully > >> performing an operation and stealing tissue from his body (by > >> excising his LAA during a routnine OPCAB), I doubt you could > >> defend that in any court of legal or medical practice, but then > >> again you may have data to answer my questions which I eagerly > >> await.> > > > > Ani> > > > > From: enaseri at hotmail.com.tr> To: > >> openheart-l at lists.hsforum.com> Subject: RE: [HSF] Routine closure > >> of the left atrial appendage?> Date: Thu,> >> 19 Jul 2007 06:28:05 +0000> > > Ani,> I would prefer to have a > >> neurologicaly intact patient with loss of some unknown endocrine > >> fx rather than a completely normal endocrinologic patient with a > >> major stroke.( and I think the patient would also vote in favor of > >> the 1.st choice.> erdinc> From: anianyanwu at hotmail.com> To: > >> openheart-l at lists.hsforum.com> Subject: RE: [HSF] Routine closure > >> of the left atrial appendage?> Date: Wed, 18 Jul 2007 20:52:15 > >> +0000> > A few years ago as a resident at Harefield I was once > >> questioned by Yacoub as to why I was virtually obliterating the RA > >> appengae while repairing a cannulation site. "The appendage is a > >> delicate organ" he said .."it must be preserved at all costs - it > >> is there for a reason". The next question which followed was "what > >> are the endocrine functions of the atrial appendage?". Indeed if > >> you watched yacoub cannulate he barely ever touched or > >> instrumented the appendage and always left the patient with this > >> structure anatomically inta> >> ct. > > This stuck with me, not because of relevance or otherwise > >> of the appendage but the realization that human bodies are complex > >> and all parts have/had a part to play. We as surgeons should > >> therefore not mutilate the human body at will and just cut and tie > >> things because we > can. Cut and do only what is necessary and > >> leave others well alone, for we do not always know why they are > >> there.> > Why don't you set up a randomized trial? If you > >> demonstrate benefit and minimal risk to routine LAA exclusion then > >> I am sure many will consider it. On the contrary if you find no > >> benefit or harm then maybe Yacoub was right - the LA appendage is > >> there for a reason and best left untouched.> > Ani> > > > > > > > >> Date: Wed, 18 Jul 2007 12:16:23 -0500> From: > >> mwertheimer at mahealthcare.com> To: OpenHeart-L at lists.hsforum.com> > >> CC: > Subject: [HSF] Routine closure of the left atrial appendage? > >> > > Given the substantial incidence of atrial fibrillation > >> following cardiac> surgery, and the frequent ne> >> ed to place many of these patients on> Coumadin anticoagulation > >> to reduce the risks of embolic stroke, has> anyone gone to > >> routinely closing off the left atrial appendage with all> cardiac > >> surgeries? It can be easily done with the use of the noncutting> > >> endo- stapling device.> > _> > >> ______________________________________________> OpenHeart-L > >> mailing list> > Send postings to:> OpenHeart-L at lists.hsforum.com> > >> > To UNSUBSCRIBE, to CHANGE email address, or to view archives:> > >> http://mmp.cjp.com/mailman/listinfo/openheart-l> > All messages > >> transmitted by the OpenHeart-L are subject to the policies and > > >> disclaimers posted at:> http://www.hsforum.com/listdisclaim> > >> -----------------------------------------> > >> _________________________________________________________________> > >> The next generation of MSN Hotmail has arrived - Windows Live > >> Hotmail> http:// > >> www.newhotmail.co.uk_______________________________________________> > >> OpenHeart-L mailing list> > Send postings to:> OpenHeart-L at lists.hsf> >> orum.com> > To UNSUBSCRIBE, to CHANGE email address, or to view > >> archives:> http://mmp.cjp.com/mailman/listinfo/openheart-l> > All > >> messages transmitted by the OpenHeart-L are subject to the > >> policies and > disclaimers posted at:> http://www.hsforum.com/ > >> listdisclaim> ------------------> -----------------------> > >> _______________________________________________> OpenHeart-L > >> mailing list> > Send postings to:> OpenHeart-L at lists.hsforum.com> > >> > To UNSUBSCRIBE, to CHANGE email address, or to view archives:> > >> http://mmp.cjp.com/mailman/listinfo/openheart-l> > All messages > >> transmitted by the OpenHeart-L are subject to the policies and > > >> disclaimers posted at:> http://www.hsforum.com/listdisclaim> > >> -----------------------------------------> > >> _________________________________________________________________> > >> Try Live.com - your fast, personalised homepage with all the > >> things you care about in one place.> http://www.live.com/?mkt=en- > >> gb _______________________________________________> OpenHeart> >> -L mailing list> > Send postings to:> OpenHeart- > >> L at lists.hsforum.com> > To UNSUBSCRIBE, to CHANGE email address, or > >> to view archives:> http://mmp.cjp.com/mailman/listinfo/openheart- > >> l> > All messages transmitted by the OpenHeart-L are subject to > >> the policies and > disclaimers posted at:> http://www.hsforum.com/ > >> listdisclaim> -----------------------------------------> >> _______________________________________________> >> OpenHeart-L mailing list> >>> >> Send postings to:> >> OpenHeart-L at lists.hsforum.com> >>> >> To UNSUBSCRIBE, to CHANGE email address, or to view archives:> >> http://mmp.cjp.com/mailman/listinfo/openheart-l> >>> >> All messages transmitted by the OpenHeart-L are subject to the > >> policies and> >> disclaimers posted at:> >> http://www.hsforum.com/listdisclaim> >> -----------------------------------------> >> >> > -- > > Ben Bidstrup FRACS FRCSEd FEBCTS> > Consultant Cardiothoracic Surgeon> > _______________________________________________> > OpenHeart-L mailing list> >> > Send postings to:> > OpenHeart-L at lists.hsforum.com> >> > To UNSUBSCRIBE, to CHANGE email address, or to view archives:> > http://mmp.cjp.com/mailman/listinfo/openheart-l> >> > All messages transmitted by the OpenHeart-L are subject to the > > policies and disclaimers posted at:> > http://www.hsforum.com/listdisclaim> > -----------------------------------------> _______________________________________________> OpenHeart-L mailing list> > Send postings to:> OpenHeart-L at lists.hsforum.com> > To UNSUBSCRIBE, to CHANGE email address, or to view archives:> http://mmp.cjp.com/mailman/listinfo/openheart-l> > All messages transmitted by the OpenHeart-L are subject to the policies and > disclaimers posted at:> http://www.hsforum.com/listdisclaim> -----------------------------------------