Background: Restenosis occurs invariably within 1 year following balloon valvulopasty in aortic valve stenosis. The mechanism of restenosis seems to involve a dynamic cellular component that could be a target for drug inhibition. We investigated the feasibility of local drug delivery at the aortic valve tissues of healthy pigs with a paclitaxel-eluting balloon.
Methods: Aortic valvuloplasty was performed in eight anesthetized domestic pigs using paclitaxel-eluting balloons (3 micro2) balloon surface area). They were assigned to two or four times 15-second balloon inflations and were sacrificed 30 minutes after final balloon inflation.
Results: The aortic annulus to balloon diameter ratio was 1.15 +/- 0.07. The mean paclitaxel concentration in the aortic valve leaflets was 0.91 +/- 1.36 micro (0.34 +/- 0.05 micro in the two-inflation group, 1.48 +/- 1.86 micro in the four-inflation group, P = 0.23). The percentage of the total paclitaxel dose recovered in the aortic valve leaflets was 18 +/- 11(-6)% (13 +/- 6(-6)% and 25 +/- 14(-6)% in the two- and four-inflation group, P = 0.16).
Conclusion: Local drug delivery at the aortic valve leaflets of healthy pigs with a paclitaxel-eluting balloon is feasible and concentrations within the therapeutic window are detected 30 minutes after the procedure. The antirestenotic potential of this treatment should be studied.