Comparison of Implantation Techniques Using Freestyle Stentless Porcine Aortic Valve

Stentless porcine aortic valves demonstrate superior hemodynamic performance when compared with their stented counterparts. The technical considerations for implanting these valves can be demanding. The Medtronic Freestyle aortic root bioprosthesis resembles an allograft, has zero-pressure-fixed leaflets treated with an antimineralization agent, and can be implanted using a variety of techniques. In this study of that valve, total root replacement (TRR) was compared with a partial scallop aortic inclusion technique (PSI). Implantations were performed in 75 patients (49 PSI and 26 TRR). There were no significant differences with respect to age, sex, or incidence of concomitant procedures. Mean aortic cross-clamp times were significantly less in the PSI group than in the TRR group (51.8 ± 11.7 minutes versus 125.5 ± 19.7 minutes; p = 0.0001). At discharge, mean systolic gradients seen on color-flow Doppler echocardiography were less in the TRR group than in the PSI group (6.17 ± 3.66 versus 10.01 ± 4.83 mm Hg; p = 0.014). Discharge echocardiography revealed trivial valve regurgitation in 8.3% of the TRR group and in 41.7% of the PSI group (p = 0.004). No patient experienced any significant valvular regurgitation on discharge echocardiography. We conclude that early experience with the Medtronic Freestyle aortic root bioprosthesis shows excellent short-term function regardless of implantation technique. Shorter cross-clamp times, comparable with those of stented valve procedures, occurred with PSI implantation. We anticipate that effects on long-term durability will be beneficial.