A retrospective study sponsored by Bayer suggested that many patients who suffered from pulmonary embolism have a higher risk of developing chronic thromboembolic pulmonary hypertension (CTEPH), a life-threatening form of pulmonary hypertension (PH). The findings indicated there is insufficient follow-up, even though the majority of the pulmonary embolism-affected patients show PH symptoms, and the risk is often under-recognized.

The research paper, “Monitoring for Pulmonary Hypertension Following Pulmonary Embolism: The INFORM Study,” was published in The American Journal of Medicine.

PH and CTEPH are common complications that may occur after a pulmonary embolism event. When symptoms lead to suspicion of PH, a ventilation-perfusion scan is the recommended diagnostic tool. CTPEH, a curable condition, is often misdiagnosed and unrecognized mostly due to shared symptoms with other more common conditions, such as asthma and chronic obstructive pulmonary disease (COPD).

In the INFORM study, researchers investigated the prevalence of PH following pulmonary embolism, and the disease monitoring patterns in 7,068 pulmonary embolism patients. The data referred to cases from July 1, 2010, to Sept. 30, 2011, and the information was collected one year before and two years after the pulmonary embolism event.

The results indicated that, among the analyzed patients, 87 percent reported a PH-related symptom, and 7.6 percent had a diagnosis of PH during follow-up. Among the patients diagnosed with PH, about half of them were also diagnosed with left heart disease, suggesting that the incidence of CTEPH could be 3.8 percent. Only 55 percent of all the patients with pulmonary embolism had diagnostic exams after the event.

“These results demonstrate that if respiratory symptoms are nonspecific and persistent in a patient with a history of pulmonary embolism, you have to have a high index of suspicion for pulmonary hypertension,” said David Platt, M.D., the study’s co-author, director of U.S. medical affairs at Bayer, in a press release. “The implications are particularly important for the subset of pulmonary embolism patients who go on to develop CTEPH. Increased awareness and use of recommended diagnostic methods, such as V/Q scans, could dramatically improve prognosis, given the availability of potentially curative surgery.”