Pulmonary Hypertension: David Badesch has spent more than 25 years chasing a disease, one so elusive that many physicians have trouble even recognizing it, much less knowing how to treat it.
It’s pulmonary arterial hypertension (PAH), a relatively rare, but extremely debilitating and even deadly disease that increases pressure in the blood vessels in the lungs, making the right side of the heart work harder. Patients suffer from shortness of breath, fatigue, heart palpitations, and limb swelling. Left untreated, it leads to right-side heart failure.
There is no cure for PAH, but that may one day change, thanks to the efforts of researchers like Badesch and his many colleagues in the Pulmonary Hypertension Center at the University of Colorado School of Medicine, a nationally recognized program specializing in research, education and treatment for PAH and the more common pulmonary hypertension, which includes left heart disease and chronic obstructive pulmonary disease (COPD).
The center’s impact extends well beyond Colorado and the Rocky Mountain region, said Badesch, professor of Medicine in CU’s Divisions of Pulmonary Sciences & Critical Care Medicine and Cardiology.
“Through our research and educational work, we’ve helped to develop guidelines for treatment of the disease,” Badesch said, “and we’ve helped to train new leaders in the field of pulmonary hypertension.” A number of other pulmonary hypertension centers around the U.S. are led by physicians who have been trained at the University of Colorado, he added.
Badesch also serves as medical director for the hospital’s Pulmonary Hypertension Clinic, where he and his colleagues follow about 1,000 patients with PAH and other forms of pulmonary hypertension. They include patients with underlying lung and heart disease.
In the 1980s, Badesch said, the median survival rate for patients with untreated idiopathic PAH – a diagnosis made when there is no identified underlying cause – was only 2.8 years. “It’s improved significantly since then,” he said, in large part because of advances in treatment.
“In 1990, there was no Food and Drug Administration-approved treatment for PAH,” Badesch said. “Now there are eight. That’s the result of clinical trials in the U.S. and internationally.”
The university and hospital have played a significant role in those discoveries, he added. “We have participated in the development of virtually every one of them,” he noted. “We often treat patients with therapies that we’ve helped to develop.” The Pulmonary Hypertension Clinic, he added, enrolls a portion of its patients in trials and treatment studies.
To fight or defeat an enemy, one must know it. To that end, the Pulmonary Hypertension Center has been a major contributor to the REVEAL (Registry to EValuate Early and Long-term pulmonary arterial hypertension disease management) Registry. REVEAL, a multi-center observational study that follows PAH patients for a minimum of five years, and collects data on demographics, underlying illnesses, treatment, and short- and long-term outcomes. The information helps to spur further research into the disease.
“We’re the second-highest enrolling center,” Badesch said, noting REVEAL patients come from throughout the Rocky Mountain region.
Badesch and his colleagues are closely involved with the Pulmonary Hypertension Assn. (PHA), which maintains a strong focus on educating medical providers about both PAH and pulmonary hypertension.
“Prompt recognition, timely diagnosis, and referral to a center of excellence are thought to be critical in ensuring effective care of the patient with PAH,” he said. Treatment delays of even a few months, he explained, may make it very difficult to stabilize the disease.
“We try to address late diagnosis with education and outreach locally and nationally,” he said. For example, the PHA sponsors preceptorships on the Anschutz Medical Campus, which give physicians from around the region a chance to increase their knowledge of the malady.
They need more information because PAH is a complex and difficult-to-recognize condition that may progress for months and even years without being detected.
“The symptoms of PAH often mimic those of other disorders,” Badesch noted. Screening for it requires an echocardiogram to get an image of the heart or a right-heart catheterization, which checks the pressure in the heart and lungs.
Following diagnosis, clinicians evaluate patients with pulmonary function tests, chest radiographs and labs to identify underlying contributing causes, including blood clots, lung disease (such as interstitial lung disease and COPD), cardiac disease, and connective tissue or autoimmune diseases.
Data from the registry have helped Badesch and others slowly sharpen the portrait of PAH. About half the patients have idiopathic pulmonary arterial hypertension, which strikes women disproportionately.
“It’s about three- or four-to-one,” Badesch noted. “And it tends to strike women who are in the prime of life.”
Some cases may be hereditary, and hormones may play a role in its targeting of women. There also appears to be a strong association between PAH and limited scleroderma, an autoimmune disease that causes, among other symptoms, tight, hardened skin.
Clinicians use three different types of therapies to treat PAH. Each targets a specific disease pathway or mechanism. In the most severe cases, patients wear a pump that delivers through an implanted catheter preset doses of a drug like epoprostenol, which dilates blood vessels. The regimen for these patients may also include oral medications.
“We’re also studying the effects of combinations of [the three targeted therapies],” Badesch said, adding the Pulmonary Hypertension Center has “multiple” clinical trials going on now. “At any one point in time, we’re involved in five to 10 or more trials,” he said.
Badesch knows the race with PAH is far from over. But he takes satisfaction in knowing he’s helped to close the gap. “It’s changed from a rapidly fatal disease to one that is treatable and controllable,” he said. “Our understanding of it is much better.”