Haemodynamic performance of a new pericardial aortic bioprosthesis during exercise and recovery: Comparison with pulmonary autograft, stentless aortic bioprosthesis and healthy control groups

Abstract

OBJECTIVES: Since blood flow impairment by aortic valve prosthesis is characteristically dynamic, this dynamic component is best and thoroughly appreciated by exercise Doppler echocardiography. We sought to determine the haemodynamics of a new pericardial aortic bioprosthesis [Trifecta™-aortic valve bioprosthesis (T-AVB), St Jude Medical, MN, USA] at rest and during exercise and a 10-min recovery period in comparison with alternative aortic valve prostheses, e.g. Ross operation (RO), stentless aortic valve [Medtronic freestyle-aortic valve bioprosthesis (MF-AVB)] and a healthy control group (CO). METHODS: Haemodynamics at rest and during supine exercise stress testing and a 10-min recovery period were evaluated in 32 patients (mean age: 70.8 ± 6.7 years) with T-AVB (mean follow-up: 5 ± 2 months), 49 with RO (mean age: 43.5 ± 13.7 years), 39 with an MF-AVB (mean age: 64.6 ± 9.4 years) and 26 healthy patients (mean age: 39 ± 9 years). Measurements included mean outflow tract gradient (δp mean, mmHg), effective orifice area index (EOAI, cm2/m2) and valvular resistance (vR, dyn s cm-5). RESULTS: Mean body surface area for T-AVB was 1.93 ± 0.24 m2 (median 1.97 m2). Mean δp mean at rest was 7.2 ± 3.4 mmHg, mean EOAI 0.86 ± 0.23 cm2/m2 and mean vR 50.7 ± 23.2 dyn s cm-5. Supine stress testing did increase the mean EOAI to 0.98 ± 0.27 cm2/m2, the mean vR to 62.6 ± 25.3 dyn s cm-5 and the mean δp mean to 10.21 ± 4.7 mmHg, respectively (P < 0.05 for all comparisons). During the post-exercise recovery period, δp mean, EOAI and vR showed a prompt normalization within 5 min of cessation of exercise. At all the three measurement points, T-AVB and MF-AVB revealed low gradients, satisfactory EOAI and low vR. Compared with the RO and a healthy control group, both groups showed significantly inferior performance throughout the exercise and post-exercise study protocol (P < 0.05). In comparison with T-AVB, patients with an MF-AVB only showed significant inferior performance throughout series with respect to a higher vR, indicating a smaller increase in the EOAI during exercise. During the 10-min post-exercise period, T-AVB recovered significantly earlier thanMF-AVB. CONCLUSIONS: When comparing two different types of aortic valve bioprostheses with a gold standard group (RO) and a healthy population, both aortic valve bioprostheses perform inferior but reveal promising haemodynamics during exercise. During post-exercise haemodynamic recovery, only the T-AVB revealed a nearly physiological recovery pattern compared with the RO and a healthy control group. © The Author 2013. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.