Pulmonary hypertension: A different kind of high blood pressure

I was diagnosed with pulmonary hypertension this past year after experiencing intermittent shortness of breath after some light activity. It also occurred following long walks on the beach.

The shortness of breath continued occasionally with walks, so I made an appointment with my primary care physician (PCP) for an exam and she recommended further in-depth testing to find the cause.

When bloodwork and a normal electrocardiogram (EKG) didn’t solve the mystery, my PCP ordered an echocardiogram which showed I had pulmonary hypertension.

This condition makes the heart work harder to pump blood into the lungs and causes the blood pressure in the lungs to be higher than normal, according to the National Heart, Lung, and Blood Institute.

Pulmonary hypertension is different from high blood pressure, also called hypertension. High blood pressure occurs when the blood flowing from your heart causes higher than normal pressure against the walls of your arteries as it travels throughout your body. When the pressure remains consistently above normal as noted with a blood pressure cuff, then you may have hypertension, according to the Centers for Disease Control and Prevention (CDC).

My condition is not that unusual, according to Timothy W. Herrick, MD, FCCP, a Cape Cod Hospital pulmonologist.

“Most of the patients I see with pulmonary hypertension have pulmonary and/or cardiovascular disease. They may have a history of chronic obstructive pulmonary disease (COPD), emphysema, or interstitial lung disease or a history of heart failure or valvular heart disease,” he said.

The list of symptoms can include shortness of breath, which is the primary complaint, fatigue, and in more severe cases, dizziness, fainting, leg edema and low oxygen levels.

While patients may be referred to Dr. Herrick for evaluation of their symptoms, the referrals often come through a cardiologist who may have diagnosed the condition as part of their evaluation.

Diagnosis

“The typical way patients are diagnosed with pulmonary hypertension is by echocardiography,” said Dr. Herrick. “The echocardiogram will show elevated pulmonary artery pressures and, if the cardiologist is not convinced it is related to cardiac disease alone, then referral to a pulmonologist is appropriate to exclude a contributing pulmonary factor.”

Dr. Herrick will do an evaluation that may include pulmonary function tests. These are performed in the Cape Cod Hospital Pulmonary Lab and include checking for the ability to inhale and exhale, measuring lung volumes, studying the diffusion of gases, respiratory muscle strength, assessing airway responsiveness, and a six-minute walking test to assess exercise capacity.

Types of Tests

Other tests that may be ordered by Dr. Herrick or a cardiologist to diagnose conditions that can cause pulmonary hypertension include:

• Chest X-ray: X-ray of the chest, lungs, heart, large arteries, ribs and diaphragm.
• Chest CT scan: A medical imaging test that produces multiple pictures of the inside of the chest and provides greater detail than X-rays.
• Sleep study: Also called polysomnography, it is a test that is done while you sleep that records and measures breathing rate, blood oxygen levels, heart rate, brain waves, leg movements, and eye movements.
• Echocardiogram: An ultrasound of the heart.
• A right heart catheterization: A catheter is inserted into a large vein in your arm, groin, or neck, and threaded through the blood vessel to your heart to measure your blood pressure in the right side of your heart and lungs.

Treatment of Pulmonary Hypertension

“We need to address the underlying cause, if possible, and that can vary substantially depending on the disease process,” said Dr. Herrick. “From my standpoint, I would be addressing the lung problems. If a patient has COPD or emphysema, treating airway obstruction with inhalers may be beneficial. If someone has low oxygen levels based on lung problems or sleep apnea, then correcting the low oxygen levels with supplemental oxygen or treating sleep apnea with continuous positive airway pressure (CPAP) will be helpful. If there is a cardiac factor, we will try to optimize medical treatment for the cardiac condition.”

“Generally, we see pulmonary hypertension that is mild to moderate,” said Dr. Herrick. “Many times, pulmonary hypertension is not unexpected based on the underlying heart or lung conditions and not much additional treatment or diagnostic workup is required. Occasionally a right heart catheterization is needed to confirm the finding of the echocardiogram.

Types of Pulmonary Hypertension

The classification of pulmonary hypertension includes the following five groups:

Group 1 – Pulmonary arterial hypertension (PAH): This type has subgroups including idiopathic PAH, hereditary PAH, PAH that occurs with other medical conditions, and PAH with past or present drug use.

Group 2 – Pulmonary hypertension associated with left heart disease

Group 3 – Pulmonary hypertension associated with lung disease such as emphysema, COPD or pulmonary fibrosis

Group 4 - Chronic thromboembolic pulmonary hypertension (CTEPH): Pulmonary hypertension due to chronic blood clots in the lungs: The body has a problem dissolving the clots which block blood flow in the lungs and cause high blood pressure.

Group 5 - Pulmonary hypertension associated with unclear or multifactorial mechanisms such as renal failure, blood disorders or sarcoidoisis.

When pulmonary hypertension is idiopathic or out of proportion to what is expected, based on underlying lung or heart conditions, a more detailed evaluation at a tertiary care pulmonary hypertension clinic may be required.