Diagnosis of Pulmonary Hypertension
Pulmonary hypertension is a complex disease. Patients have the opportunity for the best outcomes when in the care of physicians who are experts in the many aspects of the disease. Our Pulmonary Hypertension Program offers patients access to a full range of diagnostic capabilities for conditions from pulmonary fibrosis to COPD (chronic obstructive pulmonary disease).
At the time of your appointment, you will be introduced to our pulmonary hypertension nurse, who will be your contact person for future questions and pulmonary hypertension-related needs.
You will then be evaluated by one of our physicians with expertise in PH. Our advanced practice providers may also see you in conjunction with the physician. At the end of this visit, the physician will explain the diagnostic and treatment plan and discuss all relevant issues with you. Tests will be performed after the initial visit(s) to confirm if PH is present and to better define the type of PH you may have.
Tools to Diagnose Cause and Extent of PH
Many different approaches may be used to diagnose the cause and extent of PH, including:
Physical exam – During a patient visit, physicians will listen for abnormal heart and lung sounds and perform examinations to look for engorgement of the neck veins; fluid retention in the abdomen, legs and ankles; healthy nail color; and signs of underlying causes of PH.
Blood tests – May be ordered to assess for kidney and liver function, test for infection, look for anemia or an elevated red blood cell count (often found when oxygen levels are low, causing a condition called polycythemia), screen for autoimmune diseases (such as lupus or scleroderma), assess thyroid function, screen for HIV, measure oxygen levels in the blood and assess the level of “heart strain” through a brain natriuretic peptide (BNP) test.
Echocardiogram –This outpatient test uses sound waves to create a picture of the heart and its chambers. Echocardiograms are used to estimate the pressure in the lung blood vessels, show how efficiently the heart muscle is contracting and measure blood flow through the heart valves.
Chest X-ray – Used to determine if the heart muscle and lung blood vessels are enlarged or if there is lung disease present.
Six-minute walk test – Determining the distance a patient can walk in six minutes helps assess exercise tolerance and blood oxygen levels during activity. The test is often repeated at follow-up visits and is used as an objective marker of treatment response.
Pulmonary function tests – This outpatient breathing test determines how much air can go in and out of the lungs and whether the “air pipes” or “tissue” in the lungs are diseased. For the test, patients breathe in and out through a small mouth piece into a special machine that measures the lung capacity. The test is useful for gauging the severity of lung diseases such as COPD.
Polysomnogram (“sleep study”) or overnight oximetry – Sleep studies screen for sleep apnea (abnormal breathing during sleep). Patients with sleep apnea will stop breathing or develop shallow breathing during sleep, typically leading to a drop in oxygen levels. Persistent low oxygen levels can lead to pulmonary hypertension.
Pulmonary/chest CT scan – This special X-ray looks at the lungs for blood clots, excess fluid, emphysema or pulmonary fibrosis (“scarring”) that may have caused PH. An IV dye is typically injected during the test to better highlight the blood vessels in the lungs.
Ventilation perfusion scan (V/Q scan) – This nuclear medicine test looks for evidence of blood clots that have moved to the lungs. A safe protein material is injected in the vein to view the blood vessels.
Pulmonary angiogram – This test may be done if 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.
Heart catheterization – A heart catheterization is performed to confirm the presence of pulmonary hypertension and provide crucial information about optimal treatment options and long-term prognosis. Both the cardiologist and the pulmonologist discuss the results of the procedure to provide a comprehensive diagnosis. Medications may be given during the procedure to assess their effectiveness in alleviating PH.
Heart catheterization also measures pressure from the left side of the heart and the amount of blood the heart can pump each minute. Physicians may also check for blood leaks or “shunts” (such as those found in patients born with abnormal “holes” in their heart). The coronary vessels can be checked for blockage, too, only if patient needs dictate.
Follow-Up Visit Testing
During follow-up visits, your physician will order some routine tests to evaluate progression of the disease and response to the therapies. Such diagnostic tests include:
- Routine examination and labs
- Echocardiogram (performed at three- to six-month intervals)
- Six-minute walk test to measure the distance covered during a six-minute period
- Repeat heart catheterization, typically performed four to six months after initiation of treatment