Treprostinil for severe inoperable chronic thromboembolic pulmonary hypertension.
BACKGROUND
Chronic thromboembolic pulmonary hypertension (CTEPH) results from non-resolving pulmonary thromboemboli that are resistant to plasmatic anticoagulation. Because of a secondary pulmonary arteriopathy accompanying major vessel obstruction, the disorder may be a target for vasodilator therapy.


OBJECTIVE
In an open-label uncontrolled study, we investigated the prostacyclin analog treprostinil given s.c. in patients with severe inoperable CTEPH.


METHODS
Between September 1999 and September 2005, 25 patients were included if their World Health Organization (WHO) functional class was III or IV, if their six-minute walking distance (6-MWD) <or= 380 m, and if they had undergone at least one hospitalization for right heart decompensation within the prior six months, albeit not within one month before treatment start. Right heart catheterization was performed at baseline and after a minimum of 12 months (range: 12-33 months) of treatment. Treprostinil plasma concentrations were determined after at least six months of treatment. A historical group of 31 patients at our center with inoperable CTEPH matched for disease severity was used for comparative analyses.


RESULTS
Treprostinil-treated patients demonstrated significant improvements in 6-MWD (P = 0.01), WHO functional class (P = 0.001), B-type brain natriuretic peptide plasma levels (P = 0.02), cardiac outputs (P = 0.007) and pulmonary vascular resistances (P = 0.01) after 19 +/- 6.3 months. Treprostinil plasma concentrations correlated with drug dose (P < 0.001), indicating stable absorption over time. Long-term survival was significantly better than in controls.


CONCLUSIONS
Treprostinil improves exercise capacity, hemodynamics and survival in patients with severe inoperable CTEPH. We speculate that the effects may be explained by a combined vasodilatory, platelet-antagonistic and potential antiproliferative action of the drug.
Skoro-Sajer
N
N
Division of Cardiology, Vienna General Hospital, Medical University of Vienna, Vienna, Austria. nika.skoro-sajer@meduniwien.ac.at
Bonderman
D
D
Wiesbauer
F
F
Harja
E
E
Jakowitsch
J
J
Klepetko
W
W
Kneussl
M P
MP
Lang
I M
IM
D000368:Aged; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000097:blood / Q000627:therapeutic use*; D002302:Cardiac Output / Q000187:drug effects; D016022:Case-Control Studies; D002908:Chronic Disease; D011464:Epoprostenol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006976:Hypertension, Pulmonary / Q000097:blood / Q000188:drug therapy* / Q000209:etiology / Q000401:mortality; D007260:Infusion Pumps; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D016017:Odds Ratio; D010146:Pain / Q000188:drug therapy / Q000209:etiology; D010147:Pain Measurement; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage / Q000097:blood / Q000627:therapeutic use*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000097:blood / Q000150:complications* / Q000188:drug therapy / Q000401:mortality; D018570:Risk Assessment; D012720:Severity of Illness Index; D013923:Thromboembolism / Q000097:blood / Q000150:complications* / Q000188:drug therapy / Q000401:mortality; D013997:Time Factors; D016896:Treatment Outcome; D014655:Vascular Resistance / Q000187:drug effects; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000097:blood / Q000627:therapeutic use*; D016138:Walking
D000959:Antihypertensive Agents; D010975:Platelet Aggregation Inhibitors; D014665:Vasodilator Agents; D020097:Natriuretic Peptide, Brain; D011464:Epoprostenol; C427248:treprostinil