[Treatment of chronic thromboembolic pulmonary hypertension through pulmonary thromboendarterectomy and the effect of deep hypothermia circulation arrest thereon]

Abstract

Objective: To evaluate the role of the pulmonary thromboendarterectomy (PTE) in the treatment of chronic thromboembolic pulmonary hypertension (CTEPH) and the effect of the deep hypothermia circulation arrest (DHCA) thereon.

Methods: The clinical data of 40 cases of CTEPH, 25 cases of central type and 15 cases of peripheral type, 29 males and 11 females, aged 46 +/- 12 (20 - 70), underwent PTH, 17 under deep hypothermia circulatory arrest (DHCA, Group A) and 23 not under DHCA (Group B), from February 1995 to October 2006. Follow-up was conducted for 41.8 +/- 36.4 months.

Results: In the peri-operative period, no patient died in Group A and there were 6 deaths in Group B. 9 suffered with residual pulmonary hypertension and 18 with severe pulmonary reflux injury. 72 h after the PTE, the pulmonary artery systolic pressure (PASP) was 58.3 +/- 30.7 mm Hg, significantly lower than that before PTS (91.4 +/- 38.4 mm Hg, P < 0.05), the pulmonary vascular resistance (PVR) was 357 +/- 278.7 dynes x sec(-1) x cm(-5), significantly lower than that before PTE (978 +/- 675.6 dynes x sec(-1) x cm(-5), P < 0.01); the partial pressure of oxygen in the arterial blood (PaO(2)) was 89.9 +/- 7 mm Hg, significantly higher than that before the PTE (54.5 +/- 7.7 mm Hg, P < 0.01),; and the arterial oxygen saturation (SaO(2)) was 96.5 +/- 1.8%, significantly higher than that before the PTE (90 +/- 4.3%, P < 0.05). During the follow-up there were 2 late deaths, and the cardiac function was graded as NYHA class I in 22 patients, as NYHA class II in 9 patients, and as NYHA class III in 1 patient.

Conclusion: DHCA is a necessary and elementary condition for PTE, and it is a key factor in promoting the effect of PTE to treat the pulmonary reflux injury and residual pulmonary hypertension properly.