Acute treatment with Ventavis (iloprost) improves the heart’s right ventricular (RV) function in patients with idiopathic pulmonary arterial hypertension (IPAH) and PAH associated with connective tissue disease (CTD-PAH), according to a study.
The study, “Acute Iloprost Inhalation Improves Right Ventricle Function in Pulmonary Artery Hypertension: A Cardiac Magnetic Resonance Study,” was published in the journal Frontiers in Pharmacology.
Ventavis — an inhaled formation of iloprost marketed by Bayer in Europe and Actelion in the U.S. — is an effective treatment for severe pulmonary hypertension and acute RV failure. However, despite data indicating that it may lower mean pulmonary arterial pressure (mPAP) and vascular resistance, the acute effects of Ventavis on RV physiology have not been explored in detail.
Investigators at the Chinese Academy of Medical Sciences and Peking Union Medical College and Tianjin Medical University General Hospital in China aimed to address this shortcoming by using right heart catheterization (RHC) to diagnose PAH, and cardiac magnetic resonance imaging (CMR) to evaluate RV function, which is a known prognostic factor in people with PAH.
A total of 69 PAH patients were included (mean age 38 years, 53 women). All participants underwent RHC and CMR both before treatment and after receiving 5 micrograms of inhaled Ventavis. The hemodynamic (blood flow) profile of the patients indicated they all had severe PAH.
Of the participants, 23 had IPAH, 26 CTD-PAH, and 20 had PAH associated with congenital heart disease (CHD-PAH). Among patients with CTD-PAH, 15 cases were associated with systemic lupus erythematosus (SLE), four with scleroderma, and seven with mixed connective tissue disease — which has features of SLE, scleroderma, and polymyositis.
In both IPAH and CTD-PAH patients, Ventavis decreased mPAP on average by 7 mmHg, and pulmonary vascular resistance by 3 Wood units. Ventavis also reduced mPAP in a subset of CHD-PAH patients.
Furthermore, acute Ventavis inhalation immediately improved RV function, shown by increased stroke volume, ejection fraction — the amount of blood that is pumped out with each contraction — and decreased RV volume. Left ventricle systolic function also improved in patients with IPAH and CTD-PAH.
Regarding pulmonary arterial function, the only significant change seen was an improvement in pulmonary artery capacitance, an indication of the extent to which these blood vessels dilate with each contraction.
Then, the researchers found that, in patients with IPAH, the greater the improvement in RV ejection fraction, the more pronounced the reduction in pulmonary vascular resistance. No such association was found in those with CTD-PAH or CHD-PAH.
This indicated that in CTD-PAH and CHD-PAH patients, a modest decline in pulmonary vascular resistance would be associated with little to no RV ejection fraction improvement, promoting the need for more effective treatments, the team suggested.
Based on the results, the team concluded that “acutely inhaled iloprost [Ventavis] improves RV function … in patients with IPAH and CTD-PAH,” they wrote. “This knowledge is important for understanding the clinical pharmacology of Ventavis for the treatment of PAH.”