PAH Drug May Not Be of Added Benefit to Infants After Heart Surgery

Pulmonary arterial hypertension (PAH) is a common condition in infants undergoing surgery for congenital heart defects, and it is a main contributor to morbidity and death following surgery. For this reason, the drug iloprost is often given these infants after surgery, as it is known to induce blood vessel relaxation and decrease pulmonary vascular resistance. A new study, however, found that the drug offered these patients no added benefits compared to standard care.

The study, titled “The effect of intravenous iloprost on pulmonary artery hypertension after paediatric congenital heart surgery,“ was published in the journal Interactive CardioVascular and Thoracic Surgery.

Iloprost is a prostacyclin analog that is has been shown to be beneficial in PAH patients. In addition, the drug is considered safe, with very few systemic side effects. Its intravenous use in PAH secondary to congenital heart disease is, however, not well-studied, particularly in infants.

Led by Ismihan Selen Onan at Istanbul Mehmet Akif Ersoy Thoracic and Cardiovascular Surgery Education and Training Hospital, Turkey, the study enrolled 27 infants with severe PAH and scheduled for surgery. Fifteen infants were randomly chosen to receive iloprost as a continuous infusion for 72 hours postoperatively, while the others received customary care.

Researchers wanted to examine the effects, if any, that iloprost might have on PAH. The researchers found no statistical difference between the groups, with PAH occurring in two control infants and four treatment infants. Similarly, the lengths of stay in the intensive care unit and hospital did not differ between those receiving iloprost and those in the control.

The use of inotropic agents — changing the force of heart contractions — were similar in both groups, as were the rates of reintubation. The ratio of pulmonary artery over systemic pressure was also investigated after the procedure, with no differences observed. In fact, pulmonary artery pressure was not altered at all by the iloprost infusion. Pressure measured during follow-up examinations at one, seven or 30 days after surgery showed no difference among infants in the two groups.

The authors argued that the lack of benefits of iloprost treatment may be due to the fact that the drug has no additional efficacy on oxygenation in patients with PAH whose heart defect has already been corrected.

Overall, the study found that the use of intravenous iloprost is safe in infants undergoing heart surgery, but the treatment provided no benefits over standard care. The authors suggest clinicians should consider other options in infants at risk for postoperative PAH.