Early clinical and haemodynamic results after aortic valve replacement with the Freedom SOLO bioprosthesis (experience of Italian multicenter study)

OBJECTIVES: The present study investigates early clinical and haemodynamic results with the Freedom SOLO bioprosthesis (FSB) for aortic valve replacement (AVR) in eight Italian institutions. METHODS: From 2004 to 2008, a total of 229 patients [139 females (60.7%); mean age 74 ± 8 years, left ventricular (LV) ejection fraction >40%] underwent AVR with FSB. One hundred and four patients underwent preoperatively, at 1-3 and at 12 months after AVR resting transthoracic echocardiography with the effective orifice area index (EOAi) assessment, peak and mean transvalvular pressure gradients and the LV mass index (LVMi) measurement. A subset of 34 patients underwent exercise stress echocardiography at a mean of 9.6 months after AVR. RESULTS: Post-operative mortality was 3.1%. At 1-3 months, FSB showed a significant increase in the EOAi (0.39 ± 0.17 to 1.04 ± 0.17 cm(2)/m(2); P < 0.0001), a reduction in the mean gradient (43.2 ± 16.9 to 4.3 ± 2.3 mmHg; P < 0.0001) and a significant regression of the LVMi (147.6 ± 30.5 to 121.6 ± 27.4 g/m(2); P < 0.0001). During exercise stress echocardiography, the mean aortic gradients increased from 4.4 ± 1.7 at rest to 7.0 ± 2.7 mmHg at peak stress (P < 0.001). The EOA increased from 1.74 ± 0.33 to 1.80 ± 0.36 cm(2) (P = 0.0291). Mean gradients at peak stress had better correlation with resting EOAi (r = -0.74; P < 0.001) than with the prosthesis size (r = 0.43; P = 0.01). CONCLUSIONS: The supra-annular implantation of FSB offers excellent haemodynamic performance both at rest and during exercise and is associated with the rapid regression of the LV.