Surgical Aortic Valve Replacement in Small Aortic Roots for Aortic Stenosis

Objective: The aim of the present study was to analyze hemodynamic and clinical outcome of surgical aortic valve replacement (AVR) of various 19 and 21mm size stented aortic valve prosthesis.

Methods: We report a series of 572 consecutive patients with small aortic roots (mean age 75 ± 9 years, logistic predicted mortality LPM = 10.8 ± 9.3%; 1.3–78.5) undergoing AVR for aortic stenosis from 2005 to 2012. Patients received different types of porcine and bovine tissue valves. Size 19 mm and 21mm valve prostheses were used in 171 (30%) and 401 (70%) respectively. Implanted prostheses included Medtronic Mosaic (M, n = 47 (8%)), St. Jude Epic (E, n = 42 (7%)), Sorin Mitroflow (MF, 149 (26%)), Carpentier-Edwards Magna Ease (ME, n = 119 (21%)), Carpentier-Edwards Perimount Magna (PM, n = 98 (17%)), St. Jude Trifecta (TF, n = 90 (16%)) and Carpentier-Edwards Perimount (P, n = 27 (5%)) valve. Concomitant procedures such as coronary artery bypass grafting (CABG) or other valve procedures were done in 47.2% of all patients. Moderate patient prosthesis mismatch (PPM) was calculated and defined as mismatch with EOAI ≤ 0.85 cm²/m², severe mismatch with EOAI ≤ 0.65cm²/m².

Results: Moderate and severe PPM were observed in 39% and in 15% of all patients, respectively (M: 55 versus 43%, E: 74 versus 0%, MF: 49 versus 44%, ME: 16 versus 0%, M: 41 versus 0%, TF 21 versus 0%, P: 41 versus 0%). Porcine valves (M and E) revealed a significantly higher incidence of PPM than bovine valves (48 versus 87%, p < 0.001). In the bovine group severe mismatch was observed significantly more frequently in patients with the MF-prosthesis (44%) than in any other bovine valve. (p < 0.001) Five year follow-up data was available in 340 (51.2%) patients. Overall five-year survival was 31.5%. Of note, during follow-up mortality was significantly elevated in the porcine group versus the bovine group (46 vs. 21%; p < 0.001). In the prostheses sub-analysis five year mortality was significantly higher with the MF (50%) prosthesis than in any other bovine tissue valve (p < 0.05). There were no significant differences in survival rates between 19 mm and 21 mm valves after 5-years of observation.

Conclusion: The Carpentier-Edwards as well as the St. Jude Medical Trifecta valves showed the lowest incidence of PPM. While 30 days mortality was still comparable in all valve types, 5 year mortality was significantly reduced in bovine valves when compared with porcine valves.

No conflict of interest has been declared by the author(s).