Japanese single-center experience of surgery for chronic thromboembolic pulmonary hypertension

We review the outcome of surgery for chronic thromboembolic pulmonary hypertension (CTEPH).

Between 1995 and 2004, 88 patients underwent surgery for CTEPH. Mean pulmonary artery pressure and pulmonary vascular resistance were 46 mm Hg (range, 23 to 70 mm Hg) and 986 dynes.sec(-1).cm(-5) (298 to 2,231 dynes.sec(-1).cm(-5)). The pulmonary artery lesion was proximally located in 51 patients, subsegmental in 34 patients, and peripheral in 3 patients. Pulmonary endarterectomy was performed using cycles of 15-minute intermittent circulatory arrest followed by 10-minute reperfusion at 16 degrees C to 18 degrees C.

The median durations of circulatory arrest, cardiopulmonary bypass, and surgery were 58, 217, and 355 minutes, respectively. Percutaneous extracorporeal membrane oxygenation was used in 8 patients (9.1%) who had difficulty being weaning from cardiopulmonary bypass. Three recent patients for whom this was performed promptly were weaned and survived. There were 7 hospital deaths (8.0%, including 6 30-day deaths) from pulmonary bleeding in 2 patients, residual pulmonary hypertension in 3, rupture of bulla in 1, and empyema in 1. In the 81 survivors, mean pulmonary artery pressure and pulmonary vascular resistance fell significantly after surgery (p < 0.0001, each case). Age more than 60 years was a risk factor for hospital mortality on multivariate analysis. Although distal pulmonary artery disease including subsegmental and peripheral lesions was not a significant risk factor for mortality, it did influence patient recovery: the frequency of percutaneous extracorporeal membrane oxygenation was higher and hemodynamic improvement less pronounced in patients with distal disease. The actuarial survival rate was 90.7% at 3 years and 86.4% at 5 years. None of the patients have suffered recurrence. The event-free rate was 97.1% at 3 years and 93.5% at 5 years. Of the 68 patients surviving for more than 1 year after surgery, 67.6% were successfully weaned from home oxygen therapy and 13.2% required only occasional use of oxygen.

Pulmonary endarterectomy can be safely performed with relatively low mortality and favorable prognosis with long-term survival, although it should be performed carefully for patients with distal disease.