[Inhalation of a prostacyclin analog (iloprost) in primary and secondary pulmonary hypertension].
BACKGROUND
Vasodilative therapy in the form of calcium channel blockers and, recently, continuous intravenous prostacyclin has improved exercise capacity and reduced mortality in primary pulmonary hypertension. Their clinical value is limited by either low rate of response or serious side effects. These shortcomings could be overcome by the use of iloprost, a stable prostacyclin analogue. Administering it by inhalation, we assessed its short-term efficacy in patients with primary and secondary pulmonary hypertension.


METHODS
We studied six patients with primary and six with secondary pulmonary hypertension, all with New York Heart Association functional class III or IV symptoms of congestive heart failure. Iloprost was nebulised with 8 l/min of oxygen and administered in increasing doses from 10 to 40 micrograms via a facemask. The haemodynamic effects of iloprost was assessed by right-heart catheterisation.


RESULTS
Inhalation of iloprost was well tolerated, and produced a median reduction in mean pulmonary artery pressure from 52 (42-63) to 41 (35-56) mm Hg (p < 0.05). Cardiac output increased from 3.5 (2.8-4.3) to 4.1 (3.1-5.1) l/min (p < 0.05) and pulmonary vascular resistance decreased from 1036 (722-1526) to 753 (446-1107) dyn.sek.cm-5 (p < 0.01). No changes occurred in heart rate, systemic blood pressure or pulmonary wedge pressure.


CONCLUSIONS
Drug testing with inhalation of iloprost is safe and causes beneficial haemodynamic changes with selective pulmonary vasodilatation. Since the long-term effect of medical intervention is based on the degree of acute pulmonary vascular reactivity, inhalation of iloprost may be a new therapeutic option for severe pulmonary hypertension.
Andreassen
A K
AK
Hjertemedisinsk avdeling, Rikshospitalet, 0027 Oslo. arne.andreassen@rikshospitalet.no
Madsen
S
S
Kjekshus
J
J
Simonsen
S
S
D000280:Administration, Inhalation; D000328:Adult; D000368:Aged; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006976:Hypertension, Pulmonary / Q000188:drug therapy* / Q000503:physiopathology; D016285:Iloprost / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage*; D014665:Vasodilator Agents / Q000008:administration & dosage*
D010975:Platelet Aggregation Inhibitors; D014665:Vasodilator Agents; D016285:Iloprost