Worried about my Mechanic AVR's status

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Protimenow

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'What if' games, CAN drive you nuts -- but you have to know which issues you CAN play these games with, and what issues you CAN'T.

In another thread about recovery, a few instances when post-op, some patients were weak, or didn't feel right, or had other unexpected symptoms, thought enough about 'what if' (what if there's something wrong?) to call doctor or nurse, or go to E.R., and the 'what if' revealed serious post-op complications that, if not caught when they were caught, could have been fatal.). 'What if' about a minor leak in a mechanical valve is something that probably doesn't deserve playing, but other things really DO deserve second opinions. The problem - with heart valves, or any thing in life - is when playing 'what if' is a productive game, and when it's a waste of time, energy and, in some cases, emotional sanity.
 
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pellicle

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... I attribute the leaking to the leaflets being inflexible and not able to function as well as the exquisitely designed native valves.
probably not a good analogy, because inflexible ceramic valves don't typically leak (like in your bathroom or kitchen). Myself I'm unconcerned about the actual mechanism of why because:
  • I am not about to attempt a self fix
  • were there an even better new part, I know its is troublesome to re-fit a new one
  • it hasn't caused me any difficulty and the "dripping" doesn't keep my up at night ;-)
  • the "leak" is likely a small spurt and were that fixed I'd be some sort of ex-spurt ... something I've never wanted to be
 

Protimenow

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In an unpleasant experience, I've learned firsthand that, sometimes when you fix one leak, the next weakest part starts to leak. If it's my aortic valve that has a minor leak, I can live with it -- I'd certainly prefer a minor leak that I already know about to one that may pop up somewhere else.
 

carolinemc

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Modern Mechanical valves do leak by design, your st Jude does, as does mine

the hinges have a degree of regurgitation built in to help stop clots from forming.
This occurs at the periphery gap &
b-datum gap

this backwash ( leak ) is a design feature

(y)
Mine has not leaked since I got it in 2001. If it did, I would have hear the swooshing sound of a heart murmur.
 

nobog

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Mine has not leaked since I got it in 2001. If it did, I would have hear the swooshing sound of a heart murmur.
Trust me - it leaks. It is called regurgitation and it is divided into 2 parts:
1. Backflow - this is the fluid the leaflets "push back" during the closing phase.
2. Leakage - this is fluid flowing "the wrong way" during the closed part of the cycle. This is normal for the reasons stated above. The valves do not seal 100%.

So... backflow +leakage = regurgitation. This needs to be minimized because the heart just has to repeat pushing this fluid forward on the next beat. The industry measures this as a % of forward flow or ml per pulse at X condition. "X" condition is usually 70 bpm @ 5 liters per minute @ 120/80 mmHg pressure. At that condition your heart valve could typically have 5% to 15% regurgitation.

Small size mechanical valves (19mm) have much smaller backflow/leakage values than a larger (31mm) mechanical valves.

As mentioned previously, tissue valves do not have the leakage component of regurgitation (unless something is wearing out or "wrong").

JK
 

DachsieMom

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I have also been told by my surgeon that my 21mm st Jude aortic valve conduit leaks by design (my cardio freaked me out 6 weeks after surgery telling me I had a paravalvular leak and might need a redo, which wasn’t accurate but almost caused me a heart attack). I cannot recall the exact explanation, but due to it being one continuous unit it couldn’t leak, and was designed to backwash.
 

leadville

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In the interest of honesty i have removed 2 posts

during a moment of weakness i was
dragged into the net

After a coffee and a ponder normality has resumed
 
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Protimenow

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Leadville - I may have found where the term 'blood thinner' came from:

I saw some papers about the way that they tested INR years ago - and a few methods used tiny magnetic pieces in the reagent, a magnet was moving under the sample being tested. As the blood clotted, the movement of the magnetic pieces slowed, until the little magnetic shards stopped moving (the clot was formed). Strangely, they attributed the slowing of the movement of the magnetic pieces in the reagent to VISCOSITY - the blood got 'thicker' while the clot formed. Maybe if you look at a small droplet of blood, as it coagulates, you may be able to argue that the blood's viscosity rises, if the detection method moved small items in the sample. For blood with an INR of 1, it takes less time to form a clot (or slow the movement of those magnetic pieces) than it does for blood with a higher INR (it takes longer for the blood sample to get 'thick.' Normal' blood 'thickens' more rapidly than antiocoagulated blood, so it can be argued that anticoagulated blood must be 'thinner.'

Science has learned to get away from the 'thick' or 'thin' description of what an anticoagulant
(blood thinner?????) does. The 'blood thinner' description is based on an erroneous assumption made based on an early testing method.
 

leadville

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Trust me - it leaks. It is called regurgitation and it is divided into 2 parts:


So... backflow +leakage = regurgitation. This needs to be minimized because the heart just has to repeat pushing this fluid forward on the next beat. The industry measures this as a % of forward flow or ml per pulse at X condition. "X" condition is usually 70 bpm @ 5 liters per minute @ 120/80 mmHg pressure. At that condition your heart valve could typically have 5% to 15% regurgitation.

Great info Nobog

So during a Cardio workout the BP & HR will increase so would the
% of regurgitation too ?

Or would the regurgitation percentage stay the same ?
 
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leadville

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Leadville - I may have found where the term 'blood thinner' came from:

I saw some papers about the way that they tested INR years ago - and a few methods used tiny magnetic pieces in the reagent, a magnet was moving under the sample being tested. As the blood clotted, the movement of the magnetic pieces slowed, until the little magnetic shards stopped moving (the clot was formed). Strangely, they attributed the slowing of the movement of the magnetic pieces in the reagent to VISCOSITY - the blood got 'thicker' while the clot formed. Maybe if you look at a small droplet of blood, as it coagulates, you may be able to argue that the blood's viscosity rises, if the detection method moved small items in the sample. For blood with an INR of 1, it takes less time to form a clot (or slow the movement of those magnetic pieces) than it does for blood with a higher INR (it takes longer for the blood sample to get 'thick.' Normal' blood 'thickens' more rapidly than antiocoagulated blood, so it can be argued that anticoagulated blood must be 'thinner.'

Science has learned to get away from the 'thick' or 'thin' description of what an anticoagulant
(blood thinner?????) does. The 'blood thinner' description is based on an erroneous assumption made based on an early testing method.

Very interesting reading

Thanks Protime
 

nobog

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Great info Nobog

So during a Cardio workout the BP & HR will increase so would the
% of regurgitation too ?

Or would the regurgitation percentage stay the same ?
If cardiac output increases and BP and HR stay about the same, as a %, leakage will decrease but the absolute value will remain about the same.

If BP alone increases, as a % or absolute value, the leakage will increase

Backflow is design driven and will remain constant over most conditions.

It gets tricky because BP, HR, cardiac output (in liters per minute), systolic & diastolic ratios, and whether we are talking about aortic or mitral valves can make a significant difference - systolic and diastolic are "flipped" between the aortic and mitral valve.

Example - and this can vary:

Aortic at 70 bpm is about 350 ms systole and 500 ms diastole (500 ms leakage time per pulse)
Mitral at 70 bpm is about 500 ms systole and 350 ms diastole (350 ms leakage time per pulse)

So... the same valve, has a longer time period to "leak" in the aortic vs the mitral (70 bpm)

At 120 bpm its about 50/50 - 250 ms systole and 250 ms diastole.
Very low cardiac outputs mess up this formula for regurgitation as you can have as much as 30% reg and that's entirely normal (remember, the absolute value stays the same)

In the end this is about a bunch of tech stuff that has no matter to most people and your heart valve will continue to merrily tick along :)


JK
 

Agian

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I have a 27/29 On-X. Apparently, they have washjets. One banana reported it as a paravulvular leak and scared the crap out of me. So, I can empathize with DachieMom.
 

nobog

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I have a 27/29 On-X. Apparently, they have washjets. One banana reported it as a paravulvular leak and scared the crap out of me. So, I can empathize with DachieMom.
FYI, your On-X is really a 25mm valve with a larger cuff - its just the way they do things at On-X.
887168


JK
 
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