Atrial Fibrulation

This is a transcript of a talk given by Dr Andria Coley, CardioThorasic surgeon from the University of Texas, Cardiology Institute.  It deals with the present knowledge of Atrial Fibrillation as of 2022.  

Here is the URL if you prefer to watch the Video.

  https://www.youtube.com/watch?v=1-SWiGsBYqw&t=2072s

The transcript can serve as a useful check list.

1/ For decades the medical profession have had the impression that A-Fib is really not that serious.  You have an episode, get over it and carry on.

 

2/ From studies, following up on people with A-Fib it  became clear that A-Fib is a serious problem and it is becoming more and more common.  Recently a great deal of research has been carried out on A-fib, on its prognosis and how to treat it.

 

3/ People with A-Fib have a 5 times greater chance of a stroke, three times greater chance of heart failure and twice the chance of early cardiac caused death.

 

4/ A 5 year study of a group of patients who had A-fib for the first time, which was serious enough for them to be hospitalized, showed a huge increase in a whole range of conditions over the following years.  These included a high rate of heart failure, high rates of stroke, heart attacks, bleeding problems from being on blood thinners, and most serious, just under half of these patients passed away within the 5 year study period.

 

5/ A-Fib is 2 to 3 times as prevalent in the USAas in other 'western' countries.   She puts this down to the American diet, way of life and other medical problems that are common in America.

 

6/ There are a number of new options for sorting out A-Fib.

 

7/ In the healthy heart, the Sinus Node at the top of the Left Atrium starts the pulse.  The pulse is picked up by the AV node which sends it to the Ventricles.

 

Note: the blood enters the Atriums which pumps it to the ventricals which pumps it to the body (0ne side of the heart) or to the lungs (the other side).

 

8/ When a group of rogue cells 'decides' to send a false signal, it causes the Atrium to fibrillate - a little like the twitch you get in your eye sometimes.

 

9/ If this rogue signal hits the AV node it causes Rapid Ventricular Response.  ie.  The heart speeds up.  This is when people typically feel A-Fib.  When the Atrium is in A-fib, it can happen without the person being aware.  What we feel consciously is the ventricle pulsing away at a rapid rate. The complications (see below) from A-Fib occur even when only the Atrium is involved (even without the rapid Ventricular pulsing).

The Pathopysiology of A-fib

1/ AF is refractory (hard to treat).

 

2/ AF can cause heart scarring.  Electrical signals are transmited through muscle, not through scar tissue.  Scar tissue can disrupt normal signal transmission but can also be used by a surgeon to stop abnormal signal transmission.

 

3/ AF can cause the heart to stretch, further disrupting normal signalling leading to more A-Fib, leading to more stretching (and scarring).  A really bad cycle.

 

4/ Early A-Fib is called paroxysmal (comes and goes), usually from one wee cluster of cells that has gone rogue.  Usually this is on the back of the left  Atrium where the veins from the lungs enter the Atrium.

 

5/ About 6 months after this first stage, if it hasn't been taken care of, things change. Scarring and stretching begins to occur, messing up the signaling and starting what the Electro-Physiologists call a rotor.  This causes non-paroxysmal, or prolonged AF.  At this stage the new treatments that are coming on line, are useful. The old methods can't cure A-Fib at this stage in the progress of the disease.

 

6/ AF is responsible for a fifth of the strokes in the USA.

 

7/ The Atrial Appendix is one spot particularly indicated in forming clots since the blood tends to pool there, especially in someone who has AF and hence does not have a completely one-way flow of blood.

 

Note: The Atrial Appendix is a wee pocket in the wall of the heart of no known use.  A surgeon can put a plug in it if he is inside the heart or a clamp, if outside the heart.  This gets rid of the main source of blood clots. If a clamp is used, the wee pocket dies and ceases to be a problem.

 

8/ Of particular concern,  as the heart stretches, it pulls the sides of the vales apart and the valve can no longer close completely.  This allows back flow of blood and increases the chance of a clot forming and hence stroke.

  

9/ This whole process of stretching and scarring leading to more AF is a vicious downward cycle.

What can be done (in increasing order of intervention)

1/ As has been done for some time, anticoagulants are taken to avoid stroke.  Much better choices than Aspirin are available these days. Aspirin only affects the platelets and stops them clotting.  The medicine must be taken continually since one can not tell when one is in A-Fib if it doesn't trigger off the AV node, (causing the Ventricle to speed up).  Clots can form within 5 minutes of A-fib starting.

 

2/  Some people can not tolerate being on thinners.  For these folks a surgeon will often either block off or pinch off the Atrial Appendage/appendix since this is where 95% of the clots are created.  The AA isn't needed for proper heart function.

 

3/ Beta blockers are meant to stop the Ventricle from racing but they don't stop A-Fib or the complications that come with it.

 

4/  Other medications such as Amiodarone HCl are sometimes tried to re-establish normal cardiac rhythm but If AF continues, they can make one feel pretty bad.  These medicines can also affect the liver.

 

5/ Resetting the heart with a shock.  If you already have an advanced AF, the reset from a shock, likely won't last.  Shock is more effective in the very early stages of AF.

 

6/ Ablation(1), using scar tissue to stop bad signals.  Done by an Electro-Physiologist with a probe inserted through a  vein in the groin. This is for the paroxysmal (early) AF in which the rogue signal is being generated where the veins enter the Atrium from the lungs.  If AF is caught early,  it is highly effective.   When done for a later, more advanced case, success is only about 35%.

7/ Ablation (2) (when the surgeon is in your chest),  She scars a maize over your heart which only allows the good signals to propagate. Even for the really difficult cases, this technique is effective in 85 - 90% of cases.

 

8/ The best system - the Hybrid maze.

Cardio-surgeon goes in through a small incision just below the breast bone, and with a probe goes up to the heart and scars the appropriate part of the outside of the heart.  A few days later the electropysiologist goes in through a vein in the groin and finishes the job from inside.  Success is around 80%.

The Hauraki Gulf

Article in the New Zealand Press on April 19, 2022, p6, titled We're Eating the Hauraki Gulf to Death 

 

Of course we are destroying the fisheries of the Hauraki Gulf along with the fisheries resources of many other areas around New Zealand, just as we (humanity) has destroyed every other fisheries of the world. 

 

One of the most egregious, previous examples of destroying a fisheries resource was on the Grand Banks off the East Coast of Canada.  There is no one in Fisheries that isn't aware of that legendary fishing ground.  It was managed by the Canadian Fisheries Department, one of the most scientifically competent well funded fisheries departments of the world.  They allowed this huge resource to be destroyed.  

 

And in case you think, that was then and this is now, just look at our management of the Hauraki Gulf.  I challenge you to find one fisheries resource, anywhere in the world that has been properly, sustainably managed.

 

There is one way and  only one way of preserving our fisheries resources from our Hubris.  Large portions of our EEZ (Exclusive Economic Zone) must be set aside with no fishing what-so-ever being allowed in the area.  Our small existing reserves are great and seed outside areas with the young of many species but large areas seed outside areas with fully grown fish.  We must stop thinking that we know what we are doing in the ocean and simply do what has been shown to be effective. With such a system, the 'catch per unit effort' in the permitted areas will be so good that we can abandon destructive fishing methods and just use long lines. 

And don't let the scientists tell you which areas should be reserves and which areas should not.  Remember Hubris.  Remember that the scientists don't know what they are doing.  They have proven this time after time.

Here is a possibility.  You will note in the above diagram that the EEZ of New Zealand extends from about 25⁰S to about 55⁰S.  Start at the top.  From 25⁰S to 26⁰S, no fishing.  From 26⁰S to 27⁰S, fishing permitted.  From 27⁰S to 28⁰S, no fishing.  From 28⁰S to 29⁰S, fishing allowed.  And carry on like this right to the South end of our EEZ.  You could do this in 2 degree bites instead.  Whatever you do, don't let anyone manage it.  

Your only management tool is "If you fish in the no-fishing areas, your boat is confiscated and sunk.  Note that the most important aspect of any enforcement is it's inevitability.  We must pursue boats that fish in our reserves regardless of the cost and sink them.  In the not-so-long term, this will be, by far, the most economic policy.

 

And for heaven sake, ban all foreign fishing boats from our waters.  Let them destroy their own fisheries.  If we can't fish all our permitted areas then the fishing will just improve even more over our EEZ and the bottom line of our fishermen will greatly improve as their catch-per-unit-effort increases. 

 

If you do insist on licensing foreign fishing boats to fish our waters, note that the vital step is enforcement.  Any fishing boat that has it's tracker turned off is confiscated.   Any fishing boat, fishing in a forbidden area is confiscated.  Officers of these boats are jailed until a substantial fine has been paid.  Fishermen on the boats are treated really well, given a tour of New Zealand and sent home with their wages (paid by us) and memorabilia.  Imagine their attitude to their officers if they are caught again.  Fossil fuel is taken off the boats and they are sunk in no-fishing areas.  They form great reefs and will snag anyone trying to drag a net in these areas.

https://mtkass.blogspot.com/2010/12/fisheries-policy-lets-change-tacks.html

The actual warming effect of Methane

 

We often hear about the relative green house effect of Methane vs Carbon dioxide on a 20 year basis or 100 year basis.  This is a perfectly legitimate way of looking at the situation since methane is oxidized relatively rapidly in the atmosphere while Carbon dioxide remains much longer.  Carbon dioxide is taken up by various processes and notably by photosynthesis.  The half life of Methane in the atmosphere is about 7 years since it is oxidized to carbon dioxide, while the half life of Carbon dioxide is estimated at about 100 years.

 

What I'm talking about here is the relative green house gas forcing of the amount of Methane and Carbon dioxide in the atmosphere at a given moment. 

 

In this chart from1998 you can see  that the total radiative forcing of 365ppmv (parts per million by volume) of Carbon dioxide is 1.46 Watts per square meter of the earths surface.

The radiative forcing of 1.75ppmv of Methane is 0.48W per square meter.

So doing a simplistic calculation*, if Methane was 365ppmv it would have a forcing of 355/1.75 X 0.48 = 100.1Watts per square meter.

Since the forcing of the 365ppmv of Carbon dioxide is 1.46W/m2, Methane is 

100/1.46 = 68.6 times as powerful a green house gas as Carbon dioxide.

*The calculation is only a first approximation.  This has to do with the fact that the effect of green  house gasses increases a given amount for a doubling of the concentration.  It is not a linear function.  In other words the increase in the warming effect  would be the same from 100ppm to 200ppm as from 200ppm to 400ppm.

However, at present (April 2022) the concentration of Methane in the atmosphere is 1.91ppm while the concentration of Carbon dioxide is 418ppm.  The effect of Methane is equal to 1.91 X 68 = 130 ppm of Carbon dioxide.  It is, as if we had 418 + 130 = 548ppm of Carbon dioxide in the atmosphere.

What is the importance of this.  It looks as if we are destabilizing huge reservoirs of methane clatherates, both on the ocean bottom and below permafrost.  If we have major blow outs of methane, the effect on our climate could be truly catastrophic.  There will be no controlling the acceleration in warming.  The rate of rise of methane in the atmosphere is accelerating, suggesting that we have already begun to have such an effect.

Another worrying factor is that with a huge output of methane, we might overcome the mechanism in the atmosphere that is responsible for the oxidation of Methane into Carbon dioxide.  That would truly be catastrophic.

The cost of not Pyrolyzing

 Pyrolysis - heating various hydrocarbons to break them down into shorter molecules.  

Feed stock - wood, plastic, tires, used engine oil, electronic equipment etc.

Output - cooking gas, gasoline,diesel, jet fuel, road tar etc.

Let's say, for the sake of the argument, that you use renewable electricity to heat the feed stock and the energy content of the resulting products is only equal to the electrical energy that you used. ( like the processing of tar sands).  Would this be a worthwhile enterprise.  Let's look at the side benefits.

 

1/ You produce gaseous and liquid fuels which are very energy dense.  For quite a long time, we will need such fuels to power long range aircraft, heavy machinery, large trucks and so forth.

2/ You avoid the fee for sending the feed stocks to a land fill.  The pyrolysis company accepts them for free

3/  You avoid the cost of sending them overseas (plastic for instance)

4/ You avoid the cost of storing them somewhere

5/ You avoid the health costs of storing them (Piles of rubber tires breed disease carrying mosquitoes and leach poison into the environment.

6/ You avoid the cost of destroying our ocean fauna. (plastics in the ocean kill ocean animals in a range of ways).

7/ You avoid the health costs of microplastic in our environment.  The effects of microplastics are just now becoming apparent.

8/ You produce a range of valuable side products (steel and sulfur from tires, charcoal from wood)

9/ You reduce the amount of oil that must be pumped from the earth.  Pyrolyzing plastic, basically uses oil that has already been pumped (plastic is made from oil). 

10/ Pyrolyzing waste wood from the production of engineered wood, produces green fuel and sequesters carbon in buildings and in the charcoal which is incorporated into soils.  Using engineered wood, displaces concrete, a huge source of carbon dioxide.

11/ Pyrolyzing treated (tanelized) wood keeps this poisonous product from the environment and recovers the arsenic, copper and chromium.

12/ You recycle vital minerals, reducing the amount that must be mined. (electronic equipment is mostly plastic, with a range of valuable metals which can be refined ((separated)).

13/ You extend the life of waste dumps.

14/ You can pyrolyze, and thus dispose of the contents of old dumps that are problematic.

15/  We add to the amazing story of New Zealand.  We are known for such things as our amazing natural wonders, our stance on nuclear power, our grass fed meat (read The Omnivores Dilemma for the alternative - ug), how we look after visitors if they are injured while visiting, our lack of tipping and our almost unique response to Covid.    Solving our waste problems would add to this.  It all translates into cold hard cash as people want to visit and to buy our products in their own countries.

 

I'll add more as I think of them.  In actual fact, the energy content of the liquid and gaseous fuel produced is greater than the input energy by a considerable factor.  The devil is in the design of the pyrolysis units.  Have units that are designed to pyrolyze  each of the various feed stocks and it will be worthwhile having a fractionation tower to  separate the output of the units into their components.

Note that the energy content of alkanes is greater, the smaller the molecule so methane has the highest energy content than all the other alkanes.  In other words, you are adding energy to a substance as you break it down by pyrolysis.

The Omnivores Dilema

 This is a book-review of a small part of The Omnivore's Dilemma by Michael Pollan.  (starting on chapter 8).  It is the part where he describes how a farmer, Joel Salatin in the Shenandoah Valley, near Swoope, Virginia grows grass and that grass is the foundation of the whole farm.  Actually, to call it grass is a misnomer.  

 

What he is growing is a meadow of a variety of species, somewhat like what used to grow there before man arrived.  Some of the species in the Meadow are Grass, of course, both sweet and meadow, plus Fesque, Clover, Timothy, Millet, Plantain and a bunch more.  

 

Joel and others have described how the appropriate level of grazing (neither too often or too seldom) encourages the growth of a wide variety of plants and maximum total productivity.

 

The farming method is Joel's take on the theme of only grazing an area for a  short time in a  long time and then letting the meadow recover.  Typically the cows are allowed on any one area for a day and then moved to a new area. They are only allowed 'one bite'.  The rotation period varies with weather, season, rainfall and would be different in different parts of the world but it is more or less two weeks on this farm (until the cows are allowed back on a given patch of pasture).

He also 'grazes' pigs on grass (meadow) land.  The pigs are not allowed to totally trash a paddock and are moved from time to time.  Joel has found a neat way to decide when to move the pigs despite the fact that the pigs might be larger or smaller, more numerous or less numerous.  Through expenience, he has seen how much supplemental pig food to give for a given area of field.  If there are bigger pigs or more pigs, the feed will be finished quicker than if smaller or less numerous.  When the feed is finished, it is time to move the pigs.  Only experience will tell a farmer when is the best time, neither to often or too seldom, to move the pigs.

 

 In no particular order: (because one could start anywhere - the farming methods are circular going round and round).

Picture -  Fesque

 

 

Let's start with the beef cows.

First, he only grazes a given area with his beef cattle for one day, allowing only one bite of any plant at one time, never a second bite.  The plant in question balances its roots and top hamper so after being shorn/cropped, roots die back under ground*.  This is dead, energy rich, organic material which is soon consumed by the soil fauna, turning it ultimately into humus.  In other words it is building the organic content of the soil from down below.  As Joel says, the roots of some plants in a meadow go down meters so you are building a very deep soil**. 

*I knew this with respect to punning trees but never thought about it with respect to meadow plants.

**While, of course, sequestering carbon.

 

The plant then begins to grow new photosynthetic collectors (leaves) and begins to photosynthesize again.   As with all organisms, they tend to follow a sigma  growth curve.  This is a curve that starts at the origin (zero zero on a graph), rises slowly in an exponential fashion, straightens out in a very fast increase and then levels out. The following graph is about population growth but the growth of many individual species follows the same pattern.

Graph - The sigma curve

The farmer,  returns the cattle to the field in question when the plants are nearing the level-out-phase.  This way he gets the maximum  grass production possible.  Of course the plant builds new roots to balance thepart of the plant that is above ground.  Most plants exude energy rich compounds into the soil around their roots to feed the saprophytes (fungus) which bring nutrients to the plant.  Saprofites can mobilize nutrients which plants can not  (P* in particular) and which are outside the root zone of the plant.

*Some soils have a chemical make up that fixes the P that farmers put on the field into an unavailable form.  The fungus-es can mobilize this P and make it available to the plant. Some soils have huge,  stores of P which are not utilizable by plants.

 

Picture - Clover

 

 

Now we come to a neat part(one of many).  The cattle do what cattle do and leave big plate sized cow pats in the field.  Flies love to lay their eggs in this warm nutritious muck.  Apparently, the sort of fly where this farm is located has a 4 day cycle.  ie. The fly larvae (grubs) would hatch out into flies in 4 days.  So the eggmobile is brought in on day 3.  It is a trailer pulled by a tractor that houses 400 egg laying chickens.  They get to work, scattering the cow pats in every direction and picking out all those nutritious fly larvae. 

 

This farm apparently only has three external "nutrient" inputs.  One is chicken food, the second is pig food and the third is some green sand for it's mineral content.  Because of the grubs the chickens get from the cow pats plus some grass and insects, they only need three quarters as much bought-feed as would be needed for chickens that only get bought/bought-in-feed - a nice effect on the bottom line.

Picture - a beautiful eggmobile

 

The above image is not the eggmobile on Joel's farm but it is such a 'beaut', I couldn't resist including it.  Note the mobile fence in the background to confine the chickens to the area where you want them  Also note the lack of cow pats in this particular field.  This field hasn't been grazed by cows recently.  If you leave chickens on any area for an extended time, they will reduce the vegetation to zero.  Hence the advantage of having a mobile chicken house. And one last observation.  This field appears to be a monoculture, not a meadow with a wide range of plants for the grazers to eat.

 

Picture - Timothy

 

But we aren't finished with chickens yet.  Joel also raises meat chickens.  They are raised in mobile cages, each containing about 75 chickens and open on the bottom so that the chickens can access the pasture.  They are moved 'one foot print' each day so the chickens have access to fresh pasture and don't decimate a given patch.  Of course they leave their droppings on each area but not in such quantities that they 'burn' the pasture.  As you can imagine, with the above measures, the pasture growth is legendary.  Incidentally, Joel points out that if he increased his production, he would put too much organic fertilizer on his pasture and this would result in exceeding the ability of the pasture to utilize all the nutrients.  There would be a danger of runoff, polluting nearby streams.

  

Picture- Millet

 

 

Grazing has another beneficial effect.  If tall varieties are allowed to dominate, they shade out low growing plants such as clover and the variety of plants in the meadow decreases.  With this sort of management, all the plants have a chance and some farmers have observed that the variety of plants actually increases under 'proper' grazing.  

 

Of course, plants such as Clover are particularly important as they fix Nitrogen.  It is equally bad to graze too much as it is to graze too seldom.  With seldom grazing, tall plants will shade out low growing plants and the variety in the field will decrease.  With grazing too often, or grazing continually you don't take advantage of all of the growth spurt of the meadow plants and some varieties die under excessively intense grazing.  plant variety will decrease with grazing in intervals that are either too long or too short.

 

A good part of the farm is in trees, mainly on northern slopes, where they get wood for construction, fire wood and then chip all the waste wood.  These chips, are a very important part of the farm.  

 

In the three harsh months of winter the cows are housed indoors.  How neat is the following system....  Joel just keeps adding layers of either wood chip or straw for bedding but before each layer is added, he scatters a bucket of corn over the bedding.  The bedding rises up over the three months and the cows remain comfortable due to the heat generated by the bedding.  The bottom of the bedding, is, of course, anaerobic but as there is apparently no net generation of ammonia, the upper, aerobic layers are taking up this dangerous gas.  In the spring, when the cows go back out on pasture, he lets in the pigs.  He calls them his pigaerators.  They root around, mixing up the bedding, looking for those lovely ascoholic kernels of  corn and the bedding becomes aerobic, and heats up, killing any nasties that are in it.  After the pigs have finished he has some lovely fertilizer to use wherever he wants. 

 

Picture - Plantain

 

 

There is much more to The Omnivores Dilemma.   I suggest getting a copy.

 

Authors Notes

Sunshine doesn't reach into the soil.  Pretty obvious, no?  so the soil organisms have to get their energy somewhere else.  We have already described how when the top hamper of a plant is removed, the roots die down to match the top.  This energy rich organic material is available for the soil organisms.

In addition, most plants put out organic material from their roots.  Some estimates say that this is up to 30% of what they produce by photosynthesis.  They don't do this for nothing.  If it wasn't beneficial to the plant it wouldn't have evolved.  These energy rich materials feed the saprophites (fungus) that live in the soil.  In return, the saprophites can not only mobilize materials that the plant can not (notably P), but with their extensive network of hyphae, they can bring such materials from far beyond the root mass of the plant.

There is one more source of energy rich organic material.  This is any organic material that is laid down on the surface of the soil.  This includes mulch, compost and manure.  Earth worms and beetle and so forth use this material and bring it down into the soil where other organisms benefit from it or from the excrement of the worms and beetles.

 

Farm inputs

Besides a little fossil fuel for a tractor and an ATV, the only inputs to the farm are chicken feed, pig feed and Green sand. As the electric vehicle revolution proceeds, more different types of vehicle are being produced which run on electricity.  I wouldn't be surprised if eventually, Joel's tractor and ATV will run on electricity provided by solar panels on his roof.  His in-house battery will probably be a used battery from his electric car which no longer has the range he requires but is plenty grunty enough for his house. Perhaps he has already done this.  My information is far from up to date.

 

Chicken feed

When an animal eats, only 10% of the feed becomes the animal (or eggs).  The rest is excreted.  This may seem strange to you if you have fed animals and use about 2kg of feed to get 1kg of animal.  The apparent anomaly is only apparent.  It is  due to the fact that the feed is dry (typically below 7% moisture or it will spoil) while the animal is 80+% water.  

So the other 90% of the feed is excreted as Carbon dioxide, urine and feces.  This rich material is laid down on the surface of the soil and as mentioned above, is incorporated in the soil.

 

Green Sand

Also called "glauconite," greensand is a material from the ocean floor that is mined to be used as a soil conditioner or fertilizer.  It has a bluish-green color and is made of marine potash, silica, iron oxide, magnesia, lime, phosphoric acid, and about 30 other trace minerals.

In any farm, if you are continually removing  minerals from the farm as chicken and beef, you will eventually have to replace them.  In this farm, some of these minerals come in as chicken feed, some as pig feed and some as green sand.

Further reading

There are three other books that I would highly recommend.  All great reads.

1/ Dirt by David R Montgomery

In this book he describes what happens to a civilization that treats it's soil like dirt.

2/ Growing a Revolution by David R Montgomery

In this book  David describes his journey to realizing what is a better way of farming as he travels the world looking at farms in which the owner has come to this realization independently of each other. The same basic methods were arrived at from the tropics to temperate latitudes, from small holdings to huge ranches and for all sorts of crops.

3/ The Second Half of Nature by David R Montgomery

In this book he describes the inner working of a rich organic soil

4/  What your food eats.  I haven't got this one yet but it is on order.