[HSF] Redo Radical Mitral Valvuloplasty

Sat Jun 2 08:45:05 EDT 2007

Hal and Prasanna you raise interesting points.

Hal: 1) Was the pannus that you removed covering the polyester cloth of the ring? Had it involved the base of the posterior leaflet? When you describe the posterior scallops as "restricted". I presume you mean the leaflet tissue was tethered, so that when you lifted the edge of the leaflet with a leaflet retractor it was held down in the ventricular cavity. Theoretically this could occur from leaflet shrinkage (? pannus effect), chordal shrinkage (unknown in degenerative disease) or papillary displacement. I find the latter hard to attribute to correction of mitral insufficiency. If anything the ventricle should have gotten smaller with a lessening of the interpapillary and the papillary base to annular distances. (There was a study about 15 years ago of myopathic hearts in which mitral prolapse was shown to improve as the heart dilated and to get worse with improvement  in ventricular function). Is it possible that the ventricle suffered during the first operation, made enzymes or was needed  a lot of support coming off bypass? Annoying questions, I know, but it may be worth examining echo tapes from before the first op, shortly after the first op and now, and looking specifically for interpapillarydistance in systole and diastole.
2) I worry that you used autogenous pericardium in a redo. Presumably it had adhesions to the epicardium . I had bad experience with untanned pericardium that had formed adhesions due to rheumatic inflammation. There was a very rapid development of a severe sclerotic change. However the use of a brief glutaraldehyde exposure may well have eliminated a possible excessive inflammatory response.
3) I believe that leaflet enhancement was the right solution to this problem and could have been done without changing the ring.
Hal and Prasanna: Ring size in the presence of a myopathy secondary to degenerative valvular insufficiency presents interesting questions. First let me say that I do not think that a tight annuloplasty in a myopathic ventricle restores the increased  interpapillary distance to normal. To suggest, as has been done, that a tight annuloplasty restores ventricular dimensions is a hope not a fact. The problem with Barlow's is excess tissue and the reason for the very definite move by many surgeons to use larger rings is the recognition that, for years, by using intertrigonal distance as the criterion for ring choice the annulus was being reduced to a systolic dimension suitable for the leaflet dimension of a normal valve when what was needed was a larger dimension to accomodate the increased leaflet area of Barlow's pathology. Since most of the patient's with Barlow's operated these days have a compensated ventricular enlargement with good systolic function, if the ring chosen produces a systolic dimension that is the right one  to produce a proper amount of coaptation it does not matter if it  is a little larger than the dimension of systole in a normal heart. 
You have suggested that, if the heart in a Barlow's case is myopathic (and thus no longer compensated), there is a case to be made for a smaller annuloplasty.  I would suggest that smaller annuloplasties in ventricular mechanism mitral insufficiency are done because that is what is needed to produce partial compensation for the papillary displacement and leaflet tethering and reestablish at least some degree of coaptation. If ventricular improvement follows it is related to the correction of the insufficiency, but there is no evidence that annular narrowing by itself is a suitable correction for myopathy. ( What a bonanza it would be if mechanical annular reduction in the absence of mitral insufficiency was an accepted therapy for cardiomyopathy). 
Prasanna I think the paper you refer to on the better ventricular  function with larger rather than smaller prostheses was in the Asian Journal and referred to valvular prostheses, not rings. The point is appropriately made, but here we are talking about annuloplasty. I agree with you that the notion of fixing the annulus in a diastolic position is absurd. All annuloplasties that are doing their job of restoring coaptation have to be fixing the annulus in a systolic dimension. 
If in fact Barlow's is present with a severely myopathic ventricle then this would be the case for significant leaflet reduction or. perish the thought, for  backing away from the 100% repair rate  and placing a fairly small prosthesis within the native valve with due attention paid for keeping the anterior leaflet away from the septum,
Bob

:02 am
Subject: Re: [HSF] Redo Radical Mitral Valvuloplasty

I agree that downsizing is probably wise if it will not lead to SAM. The 
normal mitral circumference is 10cms and that means you would not need to 
have a diameter more than that. Also an MVOA of > 2.0 sq cm will always 
have acceptable gradients even with exercise.One important thing is that 
bigger is not necessarily better, Thus placing a large prosthesis in the 
mitral position may not be better (and an article in JVHD corroborates 
this). My reasoning is that having a smaller prosthesis or a ring will 
allow remodeling of the ventricle and will reduce its spherecity so 
implanting a large prosthesis (where leaflet weight versus flow will not 
necessarily reduce gradients (unlike in an aortic position where prostheses 
are generally smaller) and will "splint" the annulus in a "diastolic" 
position which will increase ventricular spherecity and would thus decrease 
ventricular function.The sphincteric function of the mitral annulus is lost 
with all rigid / semirigid repairs (I have pictures with radioopaque 
flexible rings showing annular motion being preserved - I think I showed 
them once in HSF) and so I think it is better to fix it at predicted 
systolic circumference/ dimensions compared to diastolic diastolic / flaccid 
dimensions. 

Myxomatous valves can be rerepaired and I congratulate you on this. 
Unfortunately the rheumatic ones which have progressed have all been due to 
posteromedial pericommissural (p3 retraction) which I have not been able to 
rerepair. 
Did you by any chance do a sliding plasty in your original repair ? One 
possible cause in my mind could due to fibrosis after a sliding 
plasty.Didthe pannusby any chance extend on to the leaflet ? 
Prasanna 

On 6/2/07, Hgrmd at aol.com <Hgrmd at aol.com> wrote: 
> 
> Dear Members, 
> Today's case was unusual. About 2 years ago, I repaired a myxomatous 
> mitral in a 38 yo lady. I placed 4 Goretex neochords in A1 and A2. I 
> closed the 
> P2-P3 interscallop leak, and performed a 
> postero-medial commissuroplasty. A 
> 32 mm Physio ring was used. She did well until a few months ago when she 
> was noted to have a recurrent MR murmur that was asymptomatic. TEE 
> revealed 
> mod-severe MR with a broad, largely central jet. I couldn't appreciate 
> any 
> recurrent prolapse. There was mod TR, normal coronaries, and an EF of 
> 40%. I 
> operated this morning and found the ring was intact and there was no 
> prolapse. 
> I removed the ring, debrided away the pannus, and inserted a 28 mm 
> Physio. 
> Saline test now revealed broad restriction of P2 and P3. I made a radial 
> slit, 2mm from the ring, along P2 and P3. Gluteraldehyde treated 
> autologous 
> pericardium was then used for posterior leaflet extension. This was done 
> with 
> continuous 5-0 Cardionyl. I also repaired the tricuspid (26mm MC3). The 
> post-CPB TEE showed no MR or TR with an EF of 30%. She was extubated on 
> the 
> table, and did well thus far. The main points are that rerepairing a 
> valve is 
> quite feasible. Certainly, with her already depressed LV function, a 
> replacement with a mechanical prosthesis would have severely clouded 
> her future. 
> Hopefully, this repair will hold up, though it worries me that 
> the posterior 
> leaflet restriction developed in the first place. I presume it was due 
> to 
> adverse ventricular remodeling. Also, Dave Adams recently had a paper in 
> Annals 
> in which he advocated using large rings for myxomatous repairs. However, 
> I 
> think this is potentially a mistake when doing myxomatous repairs in 
> hearts 
> with impaired LV's. For the myxomatous repairs in hearts with relatively 
> poor 
> LV function, you should probably undersize the ring much as you would for 
> MR 
> due to pure annular dilatation. 
> Hal 
> 
> 
> 
> ************************************** See what's free at 
> http://www.aol.com. 
> _______________________________________________ 
> 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 
> ----------------------------------------- 
> 

-- Prasanna Simha M 
_______________________________________________ 
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 
----------------------------------------- 

________________________________________________________________________
AOL now offers free email to everyone.  Find out more about what's free from AOL at AOL.com.