Acute endothelin A receptor antagonism improves pulmonary and systemic haemodynamics in patients with pulmonary arterial hypertension that is primary or autoimmune and related to congenital heart disease.
OBJECTIVE
To evaluate the acute haemodynamic effect of BQ-123, a selective endothelin A receptor antagonist, in severe chronic pulmonary arterial hypertension (PAH) of primary or autoimmune origin or related to congenital heart disease.


METHODS
Prospective open clinical study.


METHODS
Cardiology tertiary referral centre.


METHODS
26 patients with chronic PAH were studied, with mean (SEM) age 29 (3) years (range 4-71 years), mean pulmonary artery pressure 68 (4) mm Hg, and pulmonary vascular resistance index 1694 (170) dyne x s x cm(-5). Patients were divided in three groups according to PAH aetiology: primary or autoimmune PAH (n = 12), and PAH associated with congenital heart defects with (n = 6) or without (n = 8) complete mixing.


METHODS
BQ-123 200 nmol/min was infused for 60 minutes in the right atrium with sequential haemodynamic measurements at 30 minute intervals.


RESULTS
BQ-123 improved mean pulmonary artery pressure from 68 (4) to 64 (4) mm Hg (p < 0.05), pulmonary vascular resistance index from 1694 (170) to 1378 (145) dyne x s x cm(-5) (p < 0.001), pulmonary cardiac index from 3.0 (0.2) to 3.4 (0.3) l/min/m2 (p < 0.001), and effective cardiac index from 2.5 (0.2) to 2.7 (0.2) l/min/m2 (p < 0.01). Haemodynamic response was similar in all groups except for systemic cardiac index where a different (p = 0.0001, F = 5.53) response was observed; systemic cardiac index increased from 2.7 (0.2) to 2.9 (0.2) l/min/m2 (p < 0.001) when patients with complete mixing were excluded, in whom systemic cardiac index tended to decrease from 3.4 (1.0) to 3.0 (0.6) l/min/m2 (p = 0.06).


CONCLUSIONS
Acute endothelin A receptor antagonism induces substantial haemodynamic improvement in severe chronic PAH of primary or autoimmune origin or related to congenital heart disease.
Apostolopoulou
S C
SC
Department of Paediatric Cardiology, Onassis Cardiac Surgery Centre, Athens, Greece. riapos@hol.gr
Rammos
S
S
Kyriakides
Z S
ZS
Webb
D J
DJ
Johnston
N R
NR
Cokkinos
D V
DV
Kremastinos
D Th
DT
D000293:Adolescent; D000328:Adult; D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001327:Autoimmune Diseases / Q000150:complications* / Q000503:physiopathology; D001794:Blood Pressure / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D065128:Endothelin Receptor Antagonists; D005260:Female; D006330:Heart Defects, Congenital / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D006976:Hypertension, Pulmonary / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000627:therapeutic use*; D011446:Prospective Studies; D044022:Receptor, Endothelin A; D014655:Vascular Resistance / Q000187:drug effects
D000959:Antihypertensive Agents; D065128:Endothelin Receptor Antagonists; D010456:Peptides, Cyclic; D044022:Receptor, Endothelin A; C072247:cyclo(Trp-Asp-Pro-Val-Leu)