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

The present study investigates early clinical and haemodynamic results with the Freedom SOLO bioprosthesis (FSB) for aortic valve replacement (AVR) in eight Italian institutions. 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. 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). 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.