"ACHD CHAT with Richard Donner, M.D."
- Written by:
- Richard M. Donner, M.D.
- Pediatric Cardiology
- The Children's Hospital of Philadelphia
- Philadelphia, PA
Edited by: Mona Barmash
Posted: October 20,1997
Hemoptysis
- Q. Definition and causes
- A. The word "hemoptysis" means coughing up blood from the lung (not throwing up blood from the stomach). There are many diseases of the lung in which this can occur and most have nothing to do with the heart. Two well known examples are tuberculosis and cancer of the lung.
When hemoptysis is due to heart disease, there are two major causes. The most common is the presence of large, abnormal "collateral" vessels which develop in diseases where the real lung vessels are not present. Examples are tetralogy of Fallot, pulmonary atresia and tricuspid atresia. Real lung vessels receive blood from the right side of the heart (right atrium and right ventricle) which pumps unoxygenated blood into the lungs. Collateral vessels arise from the aorta, the major blood vessel which carries oxygenated blood from the left side of the heart (left atrium and left ventricle) to the body's organs. There are two problems with these collateral vessels. First, the blood delivered to the lung through the collaterals already contains some oxygen, making this setup somewhat inefficient. Second, the left ventricle pumps blood into the aorta and the collaterals at a much higher pressure than the right ventricle pumps blood into the real lung vessels. This higher pressure (among other things) causes the vessels to bleed into the lung, resulting in hemoptysis.
- The second reason hemoptysis may occur from heart disease occurs in persons with "Eisenmenger's Syndrome". Although some collateral vessels may develop here, the major reason for hemoptysis is completely different. Individuals with Eisenmenger's Syndrome have plenty of real lung vessels but they have been "damaged" by the prolonged flow of blood from the high pressure left ventricle into these vessels (remember - only low pressure blood from the right ventricle should reach these vessels). Blood from the left ventricle may reach the real lung vessels in many ways: by holes between the atria (atria septal defect), ventricles (ventricular septal defect) or even between the aorta and the pulmonary vessels, themselves (patent ductus arteriosus, aortopulmonary window, truncus arteriosus). These damaged vessels are very abnormal and can bleed into the lung causing hemoptysis.
- Q. Why would the real lung vessels not be present?
- A. The absence of real lung vessels is part of many heart abnormalities, such as tetralogy of Fallot. It is a general principle in cardiology that the heart chambers and blood vessels grow when adequate amounts of blood travel through them. Genetic factors (not necessarily inherited), which we are only beginning to understand, sometimes cause the pathway from the right ventricle into the lungs to be underdeveloped in the fetus. As the baby grows before birth, not enough blood can reach the lungs and the vessels, therefore do not grow and are very small at birth. There are other factors which contribute to the small size or absence of real lung vessels.
- Q. Why are only "some" Eisenmenger's affected by hemoptysis, while others are not?
- A. To have "Eisenmenger's Syndrome" means that the real blood vessels in the lungs are being damaged. This process occurs at vastly different rates in different people. For instance, individuals with ventricular septal defect will develop this damage must faster than those with atrial seprtal defect. Therefore, some will develop hemoptysis much earlier in life than others.
Eisenmenger's Syndrome
- Q. What does Eisenmengers Syndrome come from and what is primary and secondary pulmonary hypertension?
- A. Blood vessels in the lungs of people with no heart disease are very numerous and offer very little resistance to the flow of blood. This is why the right ventricle can pump blood into the lungs at very low pressure. In contrast, blood vessels going to the other organs of the body are less numerous and offer much more resistance to the flow of blood. This is why the left ventricle must pump at high pressure to move blood into the aorta and out to all of the organs. When there is a communication between the left and right parts of the heart, the high pressure blood will want to flow into the lungs which offer much less resistance than the blood vessels which go to the other organs. All of this blood entering the lungs causes the pressure in the lung vessels to increase. When the naturally low pressure in the lung vessels increases, we say that "pulmonary hypertension" is present (pulmonary hypertension literally means high pressure in the lung vessels). Because the high pressure is due to the abnormally high flow of blood into the lung vessels, we also say this is "secondary pulmonary hypertension". This can happen in anyone with an ASD, VSD, etc. and is not Eisenmenger's Syndrome.
- Over many years, the prolonged presence of high flow and pressure in the pulmonary arteries causes the pulmonary vessels to constrict and thicken. This constriction damages the vessels and causes their resistance to increase. This increase in resistance is the process we call Eisenmenger's Syndrome. Now, if you can follow this - when the resistance increases, the high flow of blood from the left side of the heart into the lung vessels will decrease (because the blood will no longer find it easy to enter the lung vessels) but the pressure will remain high because the lung vessels remain in contact with the high pressure in the left side of the heart. These changes are irreversible and progress over time. So, secondary pulmonary hypertension caused by high flow into the lung vessels is the major cause of Eisenmenger's syndrome.
- There is also a very rare disease in which the resistance of the lung vessels in people without heart diseease (e.g. ASD, VSD, etc.) will increase without the presence of high flow from the left side of the heart. This is called primary pulmonary hypertension.
Nose Bleeds
- Q. Does a bloody nose have a connection with achd?
- A. A bloody nose may be connected to to achd indirectly if the platelets (cells responsible for clotting) are low. Low platelets and other abnormalities of the blood clotting system often occur in people who are very blue for a long period of time. Usually, nose bleeds have nothing to do with the heart disease. Occasionally, nose bleeds may be related to high blood pressure.
Atrial Arrhythmias
- Q. What are arrhythmias?
- A. The word arrhythmia means any type of abnormal heart rhythm. This may involve the speed of the heart (too fast or too slow) or just an irregular beet at a normal speed. There are many different causes of arrhythmias but all involve some abnormality or damage to the "electrical conduction system" of the heart. It is this electrical system which carries impulses through the heart muscle and makes it contract in the proper sequence. A slow arrhythmia is usually due to injury to the natural conduction system of the heart. Some causes of arrhythmias include dilated and stretched chambers, scars from surgery, drugs given for other problems, infection or inflammation of heart tissue,and problems with the formation of the conduction system before birth.
- Q. I've read that with ACHD there is some relationship between valvular abnormalities and atrial arrythmias. Is there any relationship between valvular (pulmonary specifically) abnormalities and the development of atrial arrythmias?
- A. Yes. A valvular abnormality causes one or more chambers to enlarge and be stretched. This is one of the mechanisms which causes arrhythmias. In the case of a pulmonary valve problem (for example - following tetralogy of Fallot repair in which the pulmonary valve leaks), it is usually the right ventricle that is stretched, causing arrhythmias to come from the electrical system in this chamber.
Ablation
- Q. What is ablation?
- A. Radiofrequency ablation is a procedure, (performed with a catheter in the heart very similar to a heart catheterization), that may destroy the source of an arrhythmia and may end the need for drugs.
- Q. Is ablation an option for those of us with atrial arrythmias which developed as a complication of surgery?
- A. Ablation can be performed for many, but not all arrhythmias. It has been used effectively to treat some arrhythmias that come from surgery but it depends upon the circumstances in the individual patient.
- Q. Can anti-arrhythmic drugs (used to treat atrial fib) cause secondary heart block?
- A. Yes. Certain drugs can do this, but the heart block is usually reversible. Sometimes, the need to control the arrhythmia is so important (for example, when ablation cannot be done) that heart block must be tolerated and a pacemaker is necessary to prevent the heart from beating too slowly.
Valve Replacement
- Q. What is a homograft, and what is it used for?
- A. A homograft is a pulmonary artery (with a pulmonary valve in it) or aorta (ith an aortic valve in it) taken from a person after death. It is preserved in a special way so it will not be rejected and can be implanted in another person to replace a pulmonary artery or aorta and their respective valves. For instance, in a person with tetralogy of Fallot who has enough natural arteries in the lung itself, a pulmonary homograft can be used to replace the underdevoloped connection between the right ventricle and the natural arteries. Because it is natural tissue, a homograft may last a long time but like all things, it has advantages and disadvantages.
- Q. Do homografts usually have to be replaced later on?
- A. Homografts may have to be replaced. Their longevity is variable - from 2 to 25 years. There are 2 reasons it may have to be replaced - it may wear out or if it is placed in a growing child, a larger one will be needed when the child is more fully grown.
- Q. Is it necessary to take anti-rejection meds after a homograft? If not, why since with other cadaver organs it is?
- A. No. The methods used to preserve the homograft kill most tissue that can be rejected.
Finding ACHD centers
- Q. As you probably know, it is very hard to find someone that knows what to do with us!
- A. That's really a problem. The best place to start in any community is to contact a university with a pediatric cardiology department. They may not have an established clinic for ACHD but if they do, it will be of good quality. A listing of ACHD centers can be found in the PC Department section of this website..
Coarctation Repair
- Q. What are the new trends for fixing coarctations of the aorta?
- A. Coarctation can often be "fixed" without surgery. This involves a technique called angioplasty which uses a balloon to expand the coarctation. Coarctation of the aorta is a constriction of the aorta, the major blood vessel which sends blood to the organs of the body. The heart must pump harder to get the blood through it.
Scoliosis
- Q. What about tetralogy of Fallot and severe scoliosis that requires surgery. I read that this is not uncommon.
- A. Yes, the two often occur together for reasons that we do not fully understand. However, they are treated as they would be in a person with only one of the two problems.
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- Comment
- That makes it especially hard on the person with enlargement of the heart and a cramped upper torso to hold it all.
- A. The problem is not primarily with the heart - it is very hard to "squash" the heart. Scoliosis mostly affects the lungs by limiting their expansion. In some cases, this may affect the heart indirectly. In general, the effects of scoliosis on the lungs worsen with age. However, that doesn't mean that it happens to everyone.
Pulmonary hypertension in TOF
- Q. Do you know the percentage of TOF repairs who subsequently develop pulmonary hypertension when they have pulmonary insufficiency after repair?
- A. Pulmonary hypertension in TOF is probably rare. It does not come from pulmonary regurgitation, but is related to factors which are not understood well.
- This article was reviewed prior to publication by:
- William B. Moskowitz, M.D.
- Director of Pediatric Cardiac Catheterization Laboratory
- Director of Pediatric Heart / Lung Transplantation
- Virginia Commonwealth University / Medical College of Virginia
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