Long-Term Results After Aortic Valve Replacement with Last-Generation Stentless Prostheses.

Introduction: The purpose of this study was to evaluate the long-term clinical and hemodynamic results in patients affected by severe aortic valve disease after aortic valve replacement with third-generation stentless aortic prostheses (3F® stentless equine pericardial [Medtronic plc, Minneapolis Minnesota] and Pericarbon Freedom™ stentless bovine pericardial [LivaNova plc, London, United Kingdom]) and to analyze the benefits and the drawbacks associated to their use.

Materials and methods: Between June, 2003 and Sept, 2015 a cohort of 548 consecutive patients affected by aortic valve disease received an aortic valve replacement using a last-generation stentless pericardial aortic prosthesis at our unit. Respectively, 322 patients received a Pericarbon Freedom™ and 226 received a 3F® aortic valve. Size ranged between 19 and 29, with prevalence of 23 and 25 devices. Mean age at operation was 71± 11 years, 57% of patients were males, the mean logistic EuroScore was 8.9 ± 7.2 and 44.2% received concomitant procedures. The mean extracorporeal circulation (ECC) time was 119.2 ± 40.6. The mean cross clamp time was 90.5' ± 21.4'. In 30 patients, the aortic prosthesis was included in a Dacron tube straight graft for a Bentall operation.

Results: Early/in-hospital mortality was 2.55% (14 cases) for the entire cohort. In patients receiving isolated aortic valve replacement (AVR), it was 0.91% (5 cases). Follow up ranged between six months and 12 years (median follow-up time: 6.77 years). During follow up, 137 patients died of all causes (25%), of whom 32 patients died of cardiac causes (5.8%). Cardiac survival probability was 91% at 12 years. All surviving patients were in NYHA class I at last follow up. Actuarial freedom from structural valve deterioration was 86% at 12 years. Freedom from endocarditis was 95% at 12 years. Freedom from a valve-related reoperation at 12 years follow up was 95%. Mean residual transprosthetic gradient at 12 years was 10.3 ± 4.8MmHg.

Conclusions: Last-generation stentless pericardial valves offer excellent hemodynamics and adequate durability and freedom from structural deterioration at 12 years follow up. The implantation technique of a stentless valve is a little more demanding when compared to a stented valve, but it can be easily reproduced after minimal training. Incidence of endocarditis and thromboembolic events is low and comparable to stented pericardial valves. Young and active patients, and patients with large BSA where a patient-prosthesis mismatch may be anticipated are, in our opinion, ideal candidates to receive these kinds of valves.