This hypothetical consultation about pulmonary hypertension caused by pulmonary embolism is presented for purposes of general information. This hypothetical consultation is not medical advice. Please see your doctor to discuss your individual case and the exams and treatments that are best for you.
Doctor: Good morning. How are you?
Patient: I’m fine, thank you.
Doctor: What brings you here?
Patient: I have been referred by my primary care physician and by my pulmonary physician because I have pulmonary hypertension which has not responded to medical therapy and they think that I need some sort of surgery that you perform.
Doctor: Do you recall any time in the past having swelling or pain in your calves?
Patient: I had a deep venous thrombosis I think you call it.
Patient: It occurred on a particularly long airplane ride, I had some discomfort in my leg but the next day it was very painful and so I tried to walk it off. Then, that evening I all of a sudden got a horrible crushing chest pain and shortness of breath. My wife called the paramedics and I was brought to the hospital where they diagnosed something called a pulmonary embolus.
Doctor: As you know, a deep venous thrombosis, abbreviated DVT, is a blood clot that occurs in the deep veins of the leg and very commonly follows some sort of injury or something that leads to slow blood flow through the veins, such as sitting in the car for a long time or sitting in an airplane on a long flight. Most of the time, that deep venous thrombosis subsides by itself but occasionally the clot can break loose and go into the lungs. When it reaches the lungs, it becomes trapped in the small blood vessels of the pulmonary circulation, obstructs blood flow and causes what we term a pulmonary embolism. Now, what is unusual about the lung is that it has a double blood supply. It has a blood supply from the pulmonary arteries and the main part of the lung also has a blood supply from the aorta, blood vessels we call the bronchial arteries. The significance of this is that even though you block the pulmonary arteries the lungs will not die. Unlike if you have a blockage in your heart or brain where you have a stroke or a heart attack. That means that months or even years after this pulmonary embolism, we can open the artery and remove the blockage from the pulmonary arteries and restore flow to the lungs. Because of this unique anatomy and double blood supply the lungs will recover their function and once more will contribute to oxygenation. So, two things happen when you have a pulmonary embolism. One is that because it blocks the circulation of blood to the lungs, your heart has to work harder to push the same amount of blood through what is left of the lungs and you get a condition called pulmonary hypertension. This condition in turn leads to failure of the right side of the heart, which is the part that pumps blood to the lungs.
Patient: That’s what my doctor said that I have - pulmonary hypertension.
Doctor: Yes, well there are two very broad types of pulmonary hypertension. One, we call primary pulmonary hypertension which basically means that we don’t fully understand the cause. Albeit there are causes that we do understand such as when it runs in families or when it’s caused by certain drugs or a disease of the very fine capillaries of the lungs which can be treated with drugs or lung transplantation. But the other type is the type that you have which is caused by a mechanical obstruction, by a blood clot within the pulmonary arteries. In many people the blood clot is dissolved and they recover. In about ten percent of cases the clot is either too big or the clotting mechanism is impaired and the body can’t dissolve the blood clot, that is the embolus. With time the clot becomes fibrotic or scarred, becomes incorporated into the blood vessel wall and becomes a permanent fixed obstruction.
Patient: And you have an operation in which you remove that obstruction?
Doctor: Yes, we regularly perform an operation where we open the artery wall and remove this clot. We have one of the leading programs in the country for this treatment, and achieve unmatched outcomes of success.
Patient: What are the indications for the surgery?
Doctor: Generally, early on, somebody will go to a doctor and say, “I feel short of breath. When I sit down I’m fine but I can’t exercise anymore.” Only half the patients we see can point to having had a deep vein thrombosis or a pulmonary embolism in the past. So this can creep up on you, often without your knowing it. We call these “silent cases” and unfortunately they are difficult to diagnose in the early stages because the doctor who will examine you doesn’t have the history to go on and the examination is normal when you are sitting in his office. It’s not until you exercise that things become abnormal and it’s not until the late stages of the disease when the right side of your heart begins to fail that the disease becomes more obvious. When the right side of your heart begins to fail you get swelling of the ankles and sometimes your abdomen. There are other clinical signs that the doctor can pick up that make it more obvious, but because it’s difficult to diagnose, the average time for a patient to first go to their doctor and then eventually get referred to us is over two years.
Patient: When do I know that my problem is bad enough that I should be considering the surgery?
Doctor: Well, our strategy on that has changed over the years. Fifteen or twenty years ago, before we had our current experience in this operation, we would wait until you were really sick before we would recommend the surgery. But the operation has now become much safer. We have discovered that with time if you leave this condition unoperated, even if you are still relatively well, that you can get changes in your other arteries that become irreversible. Hence we now operate earlier when patients are still reasonably healthy. We now recommend operating as soon as you have symptoms and as soon as we can measure an increase in the blood pressure in the lungs.
Patient: How do I know that this operation is right for me at this time?
Doctor: Well, when you went to your doctor the first thing that he did was perform an echocardiogram of your heart which showed that you had high blood pressure in the right side of your heart. These tests are pretty sophisticated and we can even get a good estimate of the degree of high blood pressure. We know that once you get an elevated blood pressure, quite apart from your having symptoms, that it’s going to limit your life span and your life span becomes more limited the higher that pressure. Once we know that you have elevated right sided blood pressures there are two possibilities, the broad possibilities are either that you have primary pulmonary hypertension or that you have clots in your lungs.
Patient: Which do I have?
Doctor: Fortunately, you have clots in your lungs and I say fortunately because that is treatable.
Patient: How do you know I have clots?
Doctor: That was shown in the lung scan your doctor forwarded to me. When you have primary pulmonary hypertension there are no big defects, no big parts of the lung that don’t have perfusion. Whereas when you have clots in your lung, you can see these big air flow defects. Where the clots are, there is no air flow to the lungs in that area. So your doctor went on to the third test which is the pulmonary angiogram, which actually shows the anatomy of the pulmonary artery and the areas that are blocked.
Patient: Tell me more about the operation.
Doctor: What is necessary in the operation is that we look into the pulmonary arteries. We see where the clot is and we find a plane in the lining of the artery called the media and take out part of the lining together with the entire clot. It’s very precise work, we use special instruments and attempt to remove 100 percent of the clot. To do this we can’t have any blood flowing through the pulmonary arteries. To remove all the blood flow through the pulmonary arteries we stop the circulation completely. So we have to stop all blood flow in your body. The body does poorly with this so we cool your body and that allows us 40 or 45 minutes to operate safely. In order to cool you and to remove all the blood, we use the heart-lung machine. We use the heart lung machine every day in many heart surgery procedures. It’s a little different in this case, in that we use the heart lung machine to cool you. We cool you to 20 degrees centigrade; your normal temperature in centigrade is about 37. We operate first on one side of the lung, we start on the right side, and almost always complete the operation within about 20 minutes, which is well within our limits of safety. If it looks like we are encroaching on 30 minutes, still within the limits of safety, we’ll start the heart-lung machine for another 10 minutes until we are sure that the brain and other organs have been re-supplied with oxygen, then we stop it again. We do the same thing on the left lung and remove all the clots. The operation then involves re-warming you and letting the heart and the lungs take over the circulation.
Patient: How many of these surgeries have you performed?
Doctor: We’ve performed approximately three thousand of these operations. It’s almost an everyday event for us with about three cases a week
Patient: What happens after surgery?
Doctor: The postoperative care is much like that for other open heart surgery. You will go to the intensive care unit while we get your lungs used to the new blood supply. And then you will remain in hospital, if all goes well, for about a week to ten days. Sometimes, we send patients back home on oxygen, which is usually temporary, while the lungs get used to their new blood supply. So removing the blood clot from your lungs should result in you regaining a normal blood pressure in your right heart and allowing blood flow through your lungs so that you get oxygenation again, you can walk, exercise and not get short of breath.
Patient: When would I be able to return to my work, which is a desk job?
Doctor: We generally say about six weeks. That varies from patient to patient; it varies on your preoperative condition and your general conditioning.
Patient: And when can I return to exercise?
Doctor: About the same amount of time. As soon as you go home we would encourage you to get out of the house and walk outside the house and progressively build up the amount of exercise that you do every day with the aim of your being back to normal within about six weeks.
Patient: What are the risks and complications from this?
Doctor: They are the same as the risks as for any heart surgery, most significantly the risk of bleeding and infection. There is of course a risk of death. The risk is less for people who come to us in a relatively healthy condition. Of course when you talk about risk, you have to weigh the risk of not doing surgery, and the risk of not doing surgery depends on the severity of your pulmonary hypertension.
Patient: What do people die from as it relates to this surgery?
Doctor: People die because we can't get the blood pressure down again. When we look at the people whose blood pressure we get down adequately, the risk is significantly less. In the people that we can’t get the blood pressure down, the risk for death is greater. In those people, the reason we can’t get the pressure down is that it turns out that there was very little clot there and that all our tests have misled us and that the real cause of the problems was primary pulmonary hypertension.
I would add that sometimes we operate on people in whom we know we are not going to get perfect results. The reason we do that is there is no alternative to operation other than lung transplantation and not everybody is suitable for lung transplant or wishes to have a lung transplant and even if only part of your high blood pressure is due to blood clots we figure that if we can bring the pressure down enough it will improve your symptoms and your prognosis.
Patient: Well, I think that this is something that I need to do. How do I get this process started?
Doctor: We have a staff that will work with you. One of the issues that we often face is issues of insurance. The insurance companies often don’t know much about this condition or operation because it’s not that common. They feel that it can be done at any city or town that does heart surgery and that’s not the case. We are very accustomed to working with people and insurance companies to explain the condition, and to explain the necessity for you to come to San Diego to have the surgery. We will put you in touch with our team.
Patient: Great. Thank you.
Doctor: You’re welcome.
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