Archive for the ‘Ventricle’ Category

A disturbing report

September 23, 2010

Funky Heart reader Cindy forwarded THIS .PDF FILE that you need to read. Titled Forty Years of the Fontan Operation: A Failed Strategy, this report contains information that you should consider. Download it, print it, and read it carefully. But I’ll warn you: this report will make your hair stand up.

Forty years ago a heart defect that eliminated the Right Ventricle was “uniformly lethal” but today that same patient is “not only likely – but expected – to survive.” One of the major weapons in our arsenal is the Fontan Operation, the the Fontan comes with its own set of difficulties. The author, Dr. Jack Rychik of the Children’s Hospital of Philadelphia, considers it “a failed strategy.”

Dr. Rychik lists detailed statistics concerning the decline of Fontan patients, then explains why they tend to deteriorate: elevated central venous pressure coupled with a reduction in cardiac output. He then explains three important issues for a Fontan patient: liver damage; Plastic Bronchitis, and Protein Losing Enteropathy (PLE).

This report may be disturbing to many readers, but please remember: outcomes aren’t pre-determined. Dr. Rychik states that 40 years ago single ventricle defects were “uniformly lethal” – but I just turned 44. Heart defects aren’t like math, the answers are not so cut and dried. 2 +2 =4; 4 x 4 = 16. That’s a constant. But each defect affects the patient slightly differently, and the “standard answers” may not apply. When you are talking about a defective heart, 2+2 may equal 66.4.

Just making a guess, I believe that I know 12 to 18 people who have had the Fontan. That includes close friends, people I have met just once or twice, and some I only know through email and blogs. These people are in all stages of health – a few are doing wonderfully, most of them are doing good with occasional Bad Days, and a few can barely go. When you rank test subjects based on general health, Fontan survivors won’t be grouped around one point. They’ll be all over the place. To quote almost every Cardiologist who has ever discussed future options with a patient: It’s certainly not perfect, but it is what we have to work with.

Rychik concludes that in the past, giving a single ventricle patient the ability to live 30+ years was a noble goal. Today, it is unacceptable. He contends that Cardiologists and surgeons need to think outside of the box, and come up with new options – either redesign the Fontan (again); scrap it in favor of something else; or develop a Right Ventricle Assist Device.

Either way, every heart deserves to live a lifetime.

Just in case…

August 26, 2010

I was very pleased – to say the least! – about my exam at the Emory Adult Congenital Heart Center yesterday. An Echocardiogram showed that my Left Ventricle is 6 Millimeters smaller than the original Echo done there in 2002. It was 82 Millimeters across in 2002; it is now 76. And in my case, a shrinking heart is a 100% Official Certified GOOD THING!

If there is trouble in the future, if my PulseOx numbers were to start dropping and I was feeling worn out all the time, there are a few options that we could try to help get me back on an even keel. A couple of them are invasive but do not involve heart surgery… surgery can be a risky (and quite possibly fatal) proposition for me.

First things first, remember that 1) I am not a doctor; I’m just trying to explain it to you as it was explained to me. 2) This applies only to my heart and my health situation. Every heart defect is different, and what works for me may not be such a good thing for you… and vice versa.

The general plan for me would be to increase the blood oxygenation… but when you do that, the heart is naturally going to work harder. The trick is to find a happy balance between a decently high PulseOx and the amount of work that the heart can do. Right now my PulseOx is in the low 80% range and I have that happy balance.

The first option I would have (and all this is way in the future, if at all!) is based on my unusual anatomy. Like many reading, I have the Glenn Shunt. But mine was done in 1967, and is a completely different operation. Let’s review the difference:

The Bi-directional Glenn Shunt, the operation usually performed today: The Superior Vena Cava is cut where it joins the heart and is sewn into the Pulmonary Artery. They usually try to sew it as close to the T formed by the Pulmonary Artery to deliver an equal amount of blood to both lungs.

The Classic Glenn Shunt, performed on me in 1967: The Superior Vena Cava stays where it is. Instead of being cut, it is sewn closed. The right branch of the Pulmonary Artery is cut and sewn into the side of the Superior Vena Cava, which means that all of the blood from the Superior Vena Cava is sent into the right lung.

Now in my case, the Vena Cava wasn’t sewn completely closed. I don’t know if that was an error or if a small opening was left to relieve pressure that got too high, but a small amount of blood gets through the chokepoint and into the Right Atrium. If I were to start having problems they could use a Catheter to plug that small hole. That would cause my PulseOx to climb but shouldn’t increase the heart’s workload too much, and would probably be my best option.

The second thing they could do would be to create a fistula in my right arm. Basically, they would “short-circuit” the circulatory system by connecting an artery directly to a vein. My blood would head down my right arm as usual, but would “turn around” and head back toward the heart before it normally would. (Don’t worry,there are lots of of arterial branches and veins…. my arm wouldn’t rot and fall off!) That would increase the PulseOx numbers… but would also increase the heart’s work load. It is probably my second best option.

The third option would be a combination of medications that could reduce the natural resistance inside my body. Part of the heart’s work comes from how far the blood travels – if you could take all of the blood vessels out of an average human child and place them end to end, you’d have about 60,000 miles of blood vessels! Part of the heart’s work is because of resistance – your blood also has to turn corners and flow through organs (“Scuse me! Comin’ through!”). The medication would “grease” my blood vessels and make the blood flow through them easier. This would cause my PulseOx to rise… but not as much as any other option. My heart would also work harder. With more effort but not as many benefits, this is my third and least attractive option.

But getting a good report now gives me something better than all three of these possibilities: time. Nothing has to be done now, nor for the foreseeable future. And if I do reach the point where something needs to be done, delaying it now means that another option  could be developed that might be even better than the three ideas currently on the table.

All part of the master plan to keep pushing that final day back!

UPDATE: See Heather’s comment below for a good laugh! 🙂  Thanks, Heather!

No more heart transplants?

July 13, 2010

Will heart transplants one day be a thing of the past?

I think the answer is yes – one day. Not today, and certainly not tomorrow. But there are a lot of options being worked on that hopefully one day will help patients avoid a heart transplant. One of these we have discussed before: The Ventricular Assist Device, or VAD. The VAD is a small pump that is surgically implanted into the body and connects the ventricle to the Aorta. Technically, they can assist either ventricle, but the majority of them are connected to the Left Ventricle, the name “Left Ventricle Assistance Device” and the acronym LVAD are sometime used to discuss any variety of the pumps.

The LVAD was originally thought of as a temporary device to be used to assist a heart until a transplant organ became available, a “bridge to transplant” option. But the units have improved so much that today they are also considered as a permanent implant – “Destination Therapy” that will allow the patient to resume his or her life. With that viewpoint in mind, two important tests have recently begun.

HeartWare International recently won approval from the Food and Drug Administration (FDA) to test their LVAD system as a Destination Therapy device. HeartWare has plans to select 450 patients at 50 U.S. hospitals for the study. Patients must be in “end stage heart failure who have not responded to standard medical management and who are ineligible for cardiac transplantation.” Every patient enrolled in the study will receive an LVAD. Two thirds of them will receive HeartWare’s system, while the rest receive any other FDA-approved LVAD. The study is expected to last at least two years.

Meanwhile, World Heart Corporation is testing its new LVAD, the Levacor VAD. The Levacor VAD unit is being tested as a bridge to transplant only right now, but it is a pretty amazing little machine. The Impeller (a rotor inside the unit; the part that actually pushes the blood through) doesn’t touch anything – it is suspended in place by magnets above and below it. It turns smoother, and since it doesn’t rub against another part it should never wear out. And it is small, too – the unit is about the size of a hockey puck.

The drawback is that both LVADs require battery packs that are outside the body. Unlike pacemakers, no one has been able to implant a LVAD battery unit in the body yet. But I think that is coming, though I can’t predict when.

I get by with a little help from my HeartMate II

May 28, 2010

I’ve written about Left Ventricular Assist Devices (LVADs) before – these are small (and getting smaller!) machines designed to be attached to the Left Ventricle and give a weak heart a needed boost. Usually it is used as a “bridge to transplant” – to keep a heart going until a donor heart can be found – but more and more often they are being used as a temporary measure. The LAVD is being inserted and left in long enough for the heart to rest; if the natural pump improves the artificial one can be removed.  Robert Jarvik and a team from the University of Maryland are even developing LVADs that can be used on children and infants!

Henry Ford Hospital in Detroit Michigan has been studying LVADs and they have discovered that they help improve the right side of the heart, too. They also show that a newer model of LVAD, the HeartMate II, has a significantly lower risk of infection than its predecessor.

The HeartMate II is a continuous flow pump – unlike the earlier model, which tried to simulate the beating of the heart. Because of this, someone using a HeartMate II LVAD has almost no pulse!

I ain’t got no money, honey!

April 14, 2010

Here’s my third article about the SQUID (Superconducting QUantum Interference Device, the first two are HERE and HERE) but for this post, I’ve found a photo of the machine at work. Here it is, with the “snout” pressed against the obviously pregnant patient. There’s just one problem: Read the article that accompanies the photograph, and you’ll learn that the company that built this particular unit is no longer in business.

This is one of the more painful things about living in a bad economy, and few people realize it. The economy slows down, people lose jobs, and money becomes scarce, Medical Research is one of the fields that suffers.

Assume a Hospital/University/Drug company has a surplus that can be used in any manner they choose. Most of the money will be spent, but the account is  replenished every month. What would you do with it?

If you are head of our fictious University, you’ll probably have a lot of different groups with their hands out. Security needs some of the money – we’re obligated to keep our students safe. Housing gets some, Athletics gets a chunk, the Science department needs some… and of course, some of it will go to Research. And since our University is affiliated with a medical school and a hospital, some of that cash will be earmarked for Medical Research.

Then suddenly there is an economic downturn and our surplus isn’t as large as it once was. Everybody has to make do with less. The economic downturn morphs in to a crisis and the surplus is even less. Now something has to give, and everybody has to figure out what they can live without. Some programs and plans get shifted to the back burner, and we’ll pick them up again when things are looking brighter.

And when the medical research has to be cut back, we all suffer. Take for example the Coapsys, which is a neat little idea. The Coapsys is two pads and a string, passed through the heart and then a little bit of tension applied. The idea was that the cord could reshape an enlarged heart and force a leaky Mitral Valve to work better.

Say what? That sounds pretty far-fetched.

The funny thing is, the bloomin’ thing works! A clinical trial showed that no one who received the device had a complication during the time they were in the hospital to receive the device, and the mortality rate was about half that of those who received the traditional valve replacement.

Sounds great! The bad news is, the company that developed the device went out of business during the trials. Another company bought the Coapsys device and all intellectual property associated with it – but has no plans to further develop the device or market it. The article doesn’t say, but it might be a fair guess to assume that the financial crunch has them down, too.  No one is immune.

Thankfully the Coapsys survives, and the trials look good. And anything that shows positive results with little to no side effects, AND with a lesser chance of passing away… that device will be on the market one day.

But right now, the people who need it have to wait.

… but there is still a lot to be done

April 13, 2009

In my last post, I wrote about the amazing advances in Congenital Cardiac Surgery and how Heart Defect mortality rates have dropped 38% from 1979 to 1997. But there is still one defect we don’t have a good answer for yet: Hypoplastic Left Heart Syndrome, or HLHS.

Hypoplastic Left Heart Syndrome is not a singular defect, and could have any number of variations. But all of them feature a small (or nonexistent) Left Ventricle and a small Ascending Aorta.

If you look at a cutaway view of a normal heart, you will notice right away that while they are roughly the same size, the Right Ventricle has a larger volume than the Left Ventricle. The Right Ventricle has a smaller pumping muscle: a larger one isn’t necessary because the Right Ventricle only pumps blood to the lungs and back. But the Left Ventricle features a large, thick pumping muscle. When it contracts, the blood is really going places: out into the Aorta, and from there all over the body.

So if the Right Ventricle is content to just drive around the block, the Left Ventricle is at the airport boarding a flight to London. But in a heart with HLHS, the left Ventricle and its pumping muscle are tiny and the Aorta is barely functional. After all, the  root word for hypoplastic means “underdeveloped”. Because of this, a right sided heart defect (like Tricuspid Atresia, which is what I have) is more survivable than a left sided heart defect. 95% of children with HLHS who receive no treatment die within one week.

Even with surgery,  in the mid 1980’s only 28% of HLHS patients survived. (See the 5th Paragraph of the above link.) Until the late 1980’s an HLHS repair involved only two surgeries – The Children’s Hospital of Philadelphia (CHOP) didn’t begin to use the intermediate operation until 1989. (The entire link is informative, but page down to the section labeled “Discussion” for a look at how the three surgery procedure developed.) Current survival rates for the three stage surgical procedure are roughly 75%, with almost no data for long term survival.

This is completely unacceptable.

So what can we do about it?

1) Pass the Congenital Heart Futures Act. The Congenital Heart Futures Act, currently under review by two Congressional committees, will authorize more National Institutes of Health funding for Congenital Heart Defect (CHD) Research. Research is already going on – this January 2008 report from the National Institutes of Health (NIH) states that families with a Bicuspid Aortic Valve in their medical background are more likely to have an infant born with HLHS – but more funding means more and better tools, and more people trying to find a solution.

The Act will also create a CHD Patient Registry, maintained in one location and accessible to physicians. A properly administered registry will assemble a massive amount of data for study. The Centers for Disease Control will also develop educational programs concerning Congenital Heart Defects and their effects on patients and their families.

2) Identify Major Surgical Hubs. You aren’t going to allow a 200 bed community hospital to attempt the three surgery repair needed for HLHS. And it’s not that they are not careful, caring people… they do not have the experience. Identify the large national centers that perform many difficult medical procedures and create regional pipelines that move patients to these hospitals as quickly as possible.

3) Test new surgical theories. Gone are the days when new surgical procedures were developed through the “try it and see” method. With today’s faster computers, surgery can be simulated. A surgeon can “practice” on a computer before performing the actual operation, which give him the chance to anticipate any problems that may occur. By creating a computer simulation of an HLHS heart (multiple variations of HLHS can be programmed in, as can other defects) and using it to test new surgical theories, surgeons can explore “what if…?” theories without actually harming a patient.

4) Create a HLHS-only Registry. As a subset of the National CHD Registry, create a registry dedicated to gathering data only from patients with Hypoplastic Left Heart Syndrome. Small databases already exist and have been valuable in research: for example, researchers have used a HLHS database to  analyze the surgical approaches to HLHS to determine which ones work better. Research and better surgical procedures reduced HLHS deaths in California nearly 50% between 1990 and 2004. But such studies draw on limited databases for their information. Create a national database, and you open even more avenues for study.

5) Determine if HLHS has a genetic or an environmental origin. As noted in the January 2008 NIH report, families with an occurrence of a certain heart defect are more likely to have HLHS occur in the family later. That points to a genetic cause. But there is also evidence of an environmental factor – a “cluster” of twice as many HLHS cases than would be normally expected in a certain section of  Baltimore, Maryland. We need to devote the time and resources needed to determine what exactly causes HLHS: Is it a genetic predisposition?  Or is the environment the trigger? If it is genetic, can we learn how to prevent it? If it is environmental, what is the cause, and can we eliminate it? Or perhaps certain environmental conditions cause the genetic changes that eventually lead to HLHS.

These are just some of the things that we could do to improve Congenital Heart Defect survivability in general, and HLHS survival in particular. Quite often, we have to “think outside the box” to see the problem from an entirely different angle, and then perhaps we could find the answer.

Because every heart deserves to live a lifetime.