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Paradoxical increase of pulmonary vascular resistance during testing of inhaled iloprost

M Emmel1, B Keuth, S Schickendantz

  • 1University of Cologne, Cologne, Germany. mathias.emmel@medizin.uni-koeln.de

Heart (British Cardiac Society)
|December 17, 2003
PubMed

Insights

Inhaled iloprost, a treatment for primary pulmonary hypertension, unexpectedly caused a severe increase in pulmonary vascular resistance (PVR) in a young patient. This case highlights the potential for paradoxical reactions to this medication.

Area of Science:

  • Pediatric Cardiology
  • Pulmonary Hypertension Research
  • Pharmacology

Background:

  • Primary pulmonary hypertension (PPH) is a severe condition affecting children.
  • Domiciliary oxygen therapy is a common initial treatment.
  • Nitric oxide (NO) inhalation demonstrated a positive response, suggesting potential for vasodilator therapy.

Observation:

  • A 14-month-old girl with PPH was evaluated.
  • Inhaled nitric oxide showed a beneficial effect on pulmonary vascular resistance (PVR).
  • Subsequent testing with inhaled iloprost led to a paradoxical, severe increase in PVR.

Findings:

  • Pulmonary vascular resistance (PVR) increased from 392 to 1192 dynes x s x cm(-5) with the addition of iloprost.
  • Ventilatory and technical issues were ruled out as causes for the PVR increase.
  • This represents a rare "paradoxical" reaction to inhaled iloprost.

Implications:

  • While iloprost is generally effective for PPH, this case demonstrates a potential for adverse "paradoxical" reactions.
  • Clinicians should be aware of the possibility of severe PVR increase with iloprost in select patients.
  • Further investigation into the mechanisms of paradoxical reactions to pulmonary vasodilators is warranted.

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