Intraoperative stents to rehabilitate severely stenotic pulmonary vessels

Patch enlargement of severe branch pulmonary artery stenosis (PAS) or pulmonary vein ostial stenosis (PVS) can be technically challenging. Recurrences are common and exposure may require long periods of cardiopulmonary bypass (CPB).

Since 1993, we performed 31 procedures on 27 patients with endovascular stents placed intraoperatively under direct surgical vision: 22 patients with tight PAS and 5 patients with PVS. Selection for intraoperative (vs catheterization laboratory) stent placement was prompted by: (1) the need for a concomitant cardiac surgical procedure (16 cases); (2) limited vascular access for catheterization laboratory stent placement (11 cases); or (3) "rescue" of patients with complications after attempted placement of stents (4 cases).

In this group of very complex and challenging patients there were 5 hospital deaths (hospital survival, 81%). Follow-up of survivors has ranged from 1 month to 7 years (mean 2.8 +/- 1.7 years). There have been 3 late deaths (late "series" survival, 70%). No complication or death was related to stent placement. Surviving patients have had significant clinical improvement. Mean pulmonary gradient (postoperative vs preoperative echo) has fallen in all survivors and has decreased from a mean of 66 mm Hg preoperatively to 28 mm Hg postoperatively (p = 0.01). All pulmonary arteries are appreciably enlarged and will be easier to deal with at a later date if necessary. One patient (DORV, HLHS ) with pulmonary vein stents has gone on to a successful Glenn procedure. The other two surviving patients with PV stents have occlusion of their proximal PVs on follow-up catheterization; thus only 1 of 5 patients with stents for PVS has had a successful outcome. Four patients have had repeat surgery. Stents have produced no impediment to subsequent surgical procedures, and the pulmonary arteries were easy to work with.

Intraoperative stenting provides an attractive option for "rehabilitation" of pulmonary vessels. Direct vision insertion on CPB is extremely quick and immediately effective, limiting the CPB exposure required to treat this problem. Once stented, vessels remain open and are amenable to future surgical intervention as necessary. Outcome is better for patients with PAS versus those with PVS.