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Pulmonary Hypertension Program
Our program is the largest academic PH program in Wisconsin. While the program officially began in 2002, our PH physicians have over 20 years of combined experience diagnosing and treating this serious disease.
Given the complexity and potentially lethal nature of PH, most physicians who encounter a patient with suspected PH will refer the patient to an established pulmonary hypertension program such as ours. Our program offers consultative and continuing care services, diagnostic testing and treatment, both on an outpatient and inpatient basis.
The program is well-suited to address all complex conditions affecting the lung blood vessels including recurrent blood clots to the lungs, advanced liver disease leading to lung problems, late presentation of congenital heart disease (patients with an undiagnosed “hole in the heart”), sleep apnea, collagen vascular disease and many others.
Our board-certified pulmonary and cardiology physicians and our highly trained staff will perform an initial evaluation to determine the next steps in care. An individualized diagnostic and treatment program will be formulated, and patients will be closely monitored to make sure that a favorable response is achieved.
What tests are done to diagnose pulmonary hypertension?
Physical exam
A routine checkup will include:
- Listening for abnormal heart and lung sounds
- Examinations:
- of neck veins looking for engorgement
- of abdomen, legs and ankles looking for fluid retention
- of nail beds looking for bluish tint
- for signs of underlying diseases causing pulmonary hypertension
Blood tests
During the initial stage(s) of the diagnosis, several blood tests will likely be ordered. They include:
- Blood chemistries to examine kidney function
- Blood tests to assess liver function
- Complete blood count (CBC): tests for infection, elevated hemoglobin or anemia
- Autoantibody blood tests such as ANA, ESR and others to screen for autoimmune diseases (such as lupus or scleroderma)
- Blood tests to assess the thyroid function
- HIV to screen for human immunodeficiency virus
- Arterial blood gases (ABG) to measure oxygen levels in the blood
- Brain natriuretic peptide (BNP) to assess the level of “heart strain”
Echocardiogram
An outpatient test that uses sound waves to create a picture of the heart and its chambers. An estimate of the blood pressure in the lung blood vessels can be obtained. The test also shows whether the heart muscle contracts well or poorly and measures the amount of blood flowing through the heart valves. An arm vein may be accessed during the test to inject harmless “salty water” to better visualize heart structures and blood flow in the heart and lungs.
Chest X-ray
A chest X-ray can show whether there is an enlarged heart muscle and enlarged lung blood vessels.
Six-minute walk test
This test is used to determine the distance a person can walk during six minutes. It helps assess the exercise tolerance level and blood oxygen levels during activity. This test is repeated at most follow-up visits and is used as an objective marker of treatment response.
Pulmonary function tests
In an outpatient breathing test, a patient is asked to breathe in and out through a small mouth piece into a special machine that measures the lung capacity. This test determines how much air can go in and out of the lungs and whether the “air pipes” in the lungs are diseased.
Polysomnogram (“sleep study”) or overnight oximetry
These tests are done to screen for the presence of sleep apnea (narrowing or blockage of the windpipe). Patients with sleep apnea will either stop or develop shallow breathing during sleep. This typically leads to a drop in oxygen levels. Persistent low oxygen levels can, in turn, lead to PH after some time. The sleep study is conducted in our outpatient sleep lab. Patients arrive in the evening and spend the night in a comfortable bed while their sleep, heart rhythm, breathing pattern and oxygen levels are monitored by a technician outside the room. The data obtained during this study is reviewed by a sleep expert to determine if sleep apnea is present or not.
Chest CT scan
A special X-ray to look for the presence of blood clots, excess fluid, emphysema or fibrosis (“scarring”) of the lungs that may have caused PH. An IV dye is typically injected in this test to better highlight the blood vessels in the lungs.
Ventilation perfusion scan (V/Q scan)
A nuclear medicine test that looks for evidence of blood clots that could have moved to the lungs. A harmless contrast material is injected in the vein to view the blood vessels. Findings from this test are complementary to those obtained from the chest CT scan.
Pulmonary angiogram
This test may be done if either the chest CT scan or the V/Q scan is abnormal, or if there is a high suspicion of blockage of the lung blood vessels by blood clots. It requires injecting contrast dye into a peripheral vein to better view the lung blood vessels. Depending on test results, the treating physician may recommend a special type of surgery that removes blood clots from the lung blood vessels.
Heart catheterization
A heart catheterization is performed when the physician considers that the patient is likely to have PH. This is an outpatient procedure during which a catheter is inserted into a peripheral vein (typically a larger vein in the groin) and is advanced until it reaches the blood vessels of the lungs. This test is done to confirm the presence of PH and obtain crucial information to determine treatment options and long-term prognosis.
In the majority of cases, this is an uneventful procedure in which patients only experience minimal discomfort at the site of the catheter entrance. More detailed information is routinely provided to the patient before a catheterization is scheduled or performed. Both the cardiologist and the pulmonologist are present during the procedure to provide a more comprehensive diagnostic approach.
The procedure will help confirm if PH is present and determine the preferred therapies to treat it. Some medications may be given during the procedure to assess the degree of “stiffness” of the blood vessels and their potential to relax with medication. Such medications include intravenous prostacyclin (Flolan®), inhaled nitric oxide gas or intravenous nitroprusside.
The heart catheterization also measures the pressure coming from the left side of the heart, and measures the amount of blood the heart can pump each minute. During the test, we may also check for blood leaks between the right and left sides of the heart such as those found in patients born with abnormal “holes” in their heart. Depending on your risk factors, it might be necessary to check your coronary vessels during the same procedure.
It is possible that the catheterization will not show PH and no treatment will be indicated.
What medications are used to treat pulmonary hypertension?Once the diagnostic workup is finished, the physician will discuss the test results and will recommend possible treatment options. A specific therapy will be chosen based on several factors, including the severity of PH, the rate of disease progression and possible contraindications a patient may have to the treatment drugs.
Fortunately for patients with PH, many treatment options have been introduced in the last decade that appear to benefit even patients with more severe forms of the disease.
Therapies currently approved to treat PH include:
- Endothelin receptor antagonists — oral medications that have been shown to slow down the progression of disease (by relaxing the blood vessels in the lungs) and improve symptoms in a large percentage of patients. They include bosentan (commercially known as Tracleer®) and ambrisentan (commercially known as Letairis®). Both therapies are very safe. They carry a very small risk of liver toxicity that requires a monthly blood test to monitor the liver function to guarantee their safety.
- Phosphodiesterase-5 inhibitors — oral medications such as sildenafil (commercially known as Revatio®). It has the same component present in Viagra®, but the dose and regimen used for treatment of PH is different. They should not be used interchangeably without the approval of your treating physician.
- Prostanoids — a more complex and potent group of medications. They are usually reserved for the severe cases of PH. The group includes:
- Epoprostenol (commercially known as Flolan®) — given intravenously 24 hours a day through a permanent catheter inserted in one of the larger neck or chest veins. It requires some additional patient knowledge and involvement in the therapy to make sure the treatment is delivered safely. It was the first therapy approved for treatment of PH and the most potent so far.
- Treprostinil (commercially known as Remodulin®) — can be delivered intravenously using the same catheter used for epoprostenol (above) or through a very small plastic needle that is painlessly inserted into the skin of the abdomen. The medication is then pumped underneath the skin via the needle through an external small pump clipped to a person’s clothing.
- Iloprost (commercially known as Ventavis®) — an inhaled medication that uses a special inhalation device (medication delivery is self-triggered after each breath). It is given at least six to nine times a day, and ach treatment takes between 10-20 minutes.
Other medications that may be used in addition to the treatments mentioned above include:
- Oxygen to maintain oxygen levels above 90 percent at all times
- Anticoagulants (“blood thinners”) to decrease the formation of blood clots in lung blood vessels and improve the blood flow in the lungs
- Diuretics (“water pills”) to remove excess water from the body, allowing the heart muscle to pump easier and more efficiently
- Digoxin, an oral medication to improve the strength of the heart muscle
- Calcium channel blockers typically used for blood pressure control but may be used in a selective group of PH patients to relax the vessels in the lungs
Clinical TrialsPatients may have access to other treatment options by participating in ongoing clinical trials. Some of those trials involve experimental drugs that are in the process of being evaluated. Some studies, however, involve drugs already approved for use in PH. This is typically done when pharmaceutical companies want to obtain additional information for product safety and future development.
Fortunately for PH patients, research in this field is very active, and newer therapies are being explored and developed. During the development process, these products will be tested to confirm that they actually have a beneficial effect. Usually, pharmaceutical companies launch research studies involving people based on preliminary studies that have already suggested a potential benefit of the drug. However, this is not guaranteed, and it is important for a patient to clearly understand the risks and benefits of a research study before agreeing to participate.
In addition to providing the study medication, depending on the study, it is possible that the sponsor will pay for the basic diagnostic and follow-up tests during the duration of the study. Most of the PH studies typically run from a few months to a few years.
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