Long-term recovery of exercise ability after pulmonary endarterectomy for chronic thromboembolic pulmonary hypertension.
BACKGROUND
The exercise capacity of patients with thromboembolic pulmonary hypertension was investigated to clarify the long-term effects of pulmonary endarterectomy. This capacity was assessed by measuring cardiopulmonary factors during cardiopulmonary exercise testing at the maximal level of exercise and a 6-minute walk test at the submaximal level. Their survival rate was also determined.


METHODS
We conducted a retrospective review of the clinical records of 102 patients who underwent pulmonary endarterectomy (63 women; median age, 53 years).


RESULTS
Eight (7.8%) hospital mortalities were encountered. Three late mortalities due to fulminant hepatitis, breast cancer, and pneumonia in a patient under steroid therapy were unrelated to pulmonary endarterectomy. The actual survival rate including hospital mortalities was 90.9% at 3 years and 84.0% at 5 years. All hemodynamic measurements significantly improved and reached a plateau 1-month after endarterectomy. The cardiopulmonary exercise test at the maximal exercise level revealed that peak oxygen uptake (V(O2)) baseline was 13.8 +/- 3.2 mL/min/kg, and at 1-month was 16.2 +/- 4.2 mL/min/kg (p = 0.0015) and ventilatory response to carbon dioxide production (V(E)-V(CO2)) slope baseline was 46.5 +/- 8.4 mL/min/kg, and at 1-month was 39.9 +/- 7.4 (p = 0.0006), which gradually and significantly improved during the first year after endarterectomy (peak V(O2), 19.9 +/- 3.9 mL/min/kg [p < 0.0001] and V(E)-V(CO2) slope, 33.2 +/- 5.4 mL/min/kg [p <0.0001]). The 6-minute walk test, which reflects the systemic response at the submaximal level of functional capacity, showed that the walking distance gradually and significantly increased for up to 1 year after endarterectomy (baseline, 358 +/- 102 meters [m]; at 1-month, 433 +/- 105 m; and at 1-year, 490 +/- 80 m [p < 0.0001]) and then reached a plateau.


CONCLUSIONS
After pulmonary endarterectomy, the hemodynamic recovery occurred immediately, and the patients' exercise capacity improved during the year. The 6-minute walk test was a good indicator to assess the recovery of exercise capacity.
Matsuda
Hitoshi
H
Department of Cardio-Vascular Surgery, National Cardio-Vascular Center, Suita, Osaka, Japan. hitmat@hsp.ncvc.go.jp
Ogino
Hitoshi
H
Minatoya
Kenji
K
Sasaki
Hiroaki
H
Nakanishi
Norifumi
N
Kyotani
Shingo
S
Kobayashi
Junjiro
J
Yagihara
Toshikatsu
T
Kitamura
Soichiro
S
D000328:Adult; D000368:Aged; D002908:Chronic Disease; D004691:Endarterectomy / Q000401:mortality; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology; D005260:Female; D006439:Hemodynamics; D006801:Humans; D006976:Hypertension, Pulmonary / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010102:Oxygen Inhalation Therapy; D011651:Pulmonary Artery / Q000601:surgery*; D011655:Pulmonary Embolism / Q000150:complications / Q000503:physiopathology / Q000601:surgery*; D020127:Recovery of Function; D012189:Retrospective Studies; D016019:Survival Analysis