Pulmonary thromboendarterectomy using video-angioscopy : An alternative to cardiopulmonary transplant for post-embolic pulmonary arterial hypertension.
P Dartevelle, E Fadell, A Chapelier, P Macchiarini
Marie Lannelongue Surgical Center. Le Plessis Robinson. France
We describe an original technique of video-assisted pulmonary thromboendarterectomy, which can be used to treat occluded distal branches of the pulmonary artery.
The procedure is performed in 5 phases
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1/ After extra-pleural median sternotomy and vertical pericardotomy, extracorporeal circulation is set up between the two vena cava and the aorta. Deep hypothermia is immediately induced , and during this cooling down period, the upper vena cava is completely dissected so as to allow access to the right pulmonary artery. The left cavities are cleared so as to prevent their distension, taking into account the enormous venous return due to the bronchial hypervascularity. |
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2/ When a central temperature of 20° C is achieved, the ascending aorta is clamped. Crystaloid cardioplegia solution is infused into the root of the aorta, and repeated every 30 minutes. A longitudinal arteriotomy is carried out at the level of the right pulmonary artery in its inter-aortic and retrocaval portion. A rigid 5mm Ø endoscope is connected to a video camera and is inserted into the pulmonary artery. |
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The extracorporeal circulation is then interrupted to work in a bloodless field on the segmental and non-segmental branches of the middle and inferior lobar artery.
3/ While the arteriotomy is closed, the extracorporeal circulation is restarted so as to re-perfuse the patient for about 15 minutes, the time necessary to attain normal venous oxygen saturation.
4/ A longitudinal arteriotomy is carried out on the trunk of the pulmonary artery and extended to the left branch and the endarterectomy is performed on the left side in the same way as on the right.
5/ The patient is re-perfused during the closing of the arteriotomy, the cardiac cavities were purged, the aorta was unclamped and the patient is gradually heated to 37°C after a Swan-Ganz catheter has been placed in the trunk of the pulmonary artery.
Pulmonary endarterectomy is an endovascular procedure that can benefit from such modern technologies as video camera assistance. Apart from the illumination of the inside of the artery, the video camera provides the operator and his assistance aides access to the distal part of the artery where it divides into numerous branches. Video-assisted angioscopy allows us to improve the quality of the endarterectomy in terms of the number of unblocked branches, and in consequence, reduction of pulmonary vascular resistance. This surgical technique can replace cardiopulmonary transplant in most cases.The indications for this procedure are a function of the technical feasibility and the experience of the surgeon. The lesions have to be sufficiently proximal, that is to say, must start at the level of the trunks of the pulmonary arteries or at the level of the lobar arteries, so that an endarterectomy can be performed. When the haemodynamics correspond to the degree of obstruction, a good result is obtained in most cases. On the other hand in serious forms where the resistance is higher than the anatomic lesions seen on angiogram would suggest, endarterectomy should only be considered if one believes it is possible to reduce pulmonary resistance by 50%.
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EVOLUTION DES PARAMETRES HEMODYNAMIQUES (42 PATIENTS) |
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NYHA |
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PAP Moy (mmHg) |
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Q (L/min) |
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IC (L/min/m2) |
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Svo2 (%) |
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RVPT (dynes/s.cm-5) |
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