Pulmonary Hypertension

The normal peak pulmonary artery pressure is approximately 25 mm Hg, while PH patients have pressures above 40 mm Hg. The pulmonary arteries deliver blood from the right side of the heart to the lungs to pick up oxygen; and the right side of the heart becomes enlarged, if it has to pump against high pressures in the pulmonary arteries. As PH progresses, the right heart may have increasing difficulty and ultimately may fail.

Symptoms
Symptoms of pulmonary hypertension include shortness of breath, tiredness, cough, dizziness or fainting spells, chest pain, and swelling in the ankles or abdomen. Since PH is such an unusual disease, often these symptoms have become quite severe before a diagnosis is made.

Diagnosis
Testing must be done to evaluate for secondary causes of pulmonary hypertension. Therefore, an electrocardiogram (EKG), chest x-ray, echocardiogram, ventilation perfusion scan, and pulmonary function tests help to eliminate other causes for pulmonary hypertension. Blood work including thyroid functions and serology for ANA and HIV also can help determine secondary causes. Often pulmonary angiography, computed tomography (CAT scan) or sleep studies may be beneficial in diagnosing the cause. Cardiac catherization is done to diagnose and determine the severity of the pressures in the pulmonary arteries, exclude congenital heart defects, and measure response to medications.

Treatment
Treating PH with medications that dilate the pulmonary arteries can improve symptoms and the strain on the right side of the heart. Medication that make the blood flow easier through the pulmonary arteries called anticoagulants, and that pull off fluid from the body called diuretics are also used. Calcium channel blockers are a medication taken by mouth that in some patients, lower the pressure in the pulmonary arteries. Oxygen can prevent further constriction of the pulmonary arteries when oxygen levels in the blood are low.

A medication called Flolan^® imitates a naturally occurring chemical in the body, called prostacyclin, that dilates blood vessels, including the pulmonary arteries. Flolan^® is an intravenous medication, which is infused through a permanent catheter in the chest, called a central line. A pump ensures this medication is delivered at a slow and continuous rate, because this medication can not be interrupted. Flolan^® can have effects of flushing, nausea, diarrhea, headaches, and jaw pain and can be complicated by central line infections. Since this medication is complex to administer, it needs to be given by health professionals with expertise in this area.

Further research is constantly looking for ways to treat PH without the risks of an intravenous medication. Bosentan^® is a pill which blocks a hormone called endothelin. Endothelin is made in the lung and is found in higher levels in PH patients, leading to resistance of blood flow through the lungs and higher pressures in the pulmonary arteries. Bosentan^® has recently been approved by the F.D.A., as an approved therapy for PH.

A medication given continually under the skin, (which eliminates the need for a central line) is called Remodulin^®. This medication requires less frequent mixing, and does not need to be kept chilled as does Flolan^®, but does not have as strong of dilating effects. Remodulin^® is being reviewed by the F.D.A., as an approved therapy for PH.

Iloprost^® is an inhaled form of prostacyclin, which dilates pulmonary arteries and lowers pulmonary artery pressures. It is still in the study phase and does not have F.D.A. approval.

Beraprost^® is a pill form of prostacyclin, which continues to be researched for it’s effects on PH, and is not approved by the F.D.A.

Visit UI Health Care on the web for more information about UI Heart and Vascular Center's Pulmonary Hypertension Program.

Last Reviewed 2005

Source: Traci Stewart, R.N., B.S.N.
UI Heart and Vascular Center, Pulmonary Hypertension Program
University of Iowa Hospitals and Clinics

Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.