Duration of right ventricular contraction predicts the efficacy of bosentan treatment in patients with pulmonary hypertension.
OBJECTIVE
In patients with pulmonary hypertension (PH), elevated endothelin-1 levels are associated with prolonged duration of right ventricular (RV) contraction, which induces leftward ventricular septal bowing with impaired left diastolic filling. We hypothesized that baseline RV contraction duration predicts efficacy of endothelin receptor antagonist, bosentan.


RESULTS
Eighteen PH patients (age 57, range 35-79 years, 33% male) received bosentan. Six minute walk distance (6-MWD) and echocardiography were performed at baseline and after 1 year follow-up. After 1 year of treatment, 6-MWD increased (mean 60 +/- 41 m) in 67% of patients (responders). Baseline RV contraction duration was longer in responders, compared with non-responders (612 +/- 66 vs. 514 +/- 23 ms; P < 0.01). A baseline RV contraction duration >550 ms was associated with improved 6-MWD (sensitivity 83%, specificity 83%; P < 0.01).


CONCLUSIONS
An improvement of 6-MWD during bosentan treatment was associated with a decrease in RV contraction duration and could be predicted by a baseline RV contraction duration >550 ms.
Duffels
Mariëlle G J
MG
Department of Cardiology, Academic Medical Center, Amsterdam, The Netherlands.
Hardziyenka
Maxim
M
Surie
Sulaiman
S
de Bruin-Bon
Rianne H A C M
RH
Hoendermis
Elke S
ES
van Dijk
Arie P J
AP
Bouma
Berto J
BJ
Tan
Hanno L
HL
Berger
Rolf M F
RM
Bresser
Paul
P
Mulder
Barbara J M
BJ
D000328:Adult; D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D000077300:Bosentan; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006976:Hypertension, Pulmonary / Q000000981:diagnostic imaging / Q000188:drug therapy; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D012189:Retrospective Studies; D013449:Sulfonamides / Q000627:therapeutic use*; D016896:Treatment Outcome; D014463:Ultrasonography; D016278:Ventricular Function, Right / Q000187:drug effects*; D016138:Walking
D000959:Antihypertensive Agents; D013449:Sulfonamides; D000077300:Bosentan