2 The condition, current treatments and procedure
2.1 Aortic valve disease (stenosis or regurgitation) is usually progressive, causing an increase in cardiac workload, left ventricular hypertrophy and heart failure. Symptoms can include palpitations, fatigue, shortness of breath, syncope and chest pain on exertion. Mortality rates are high in people who have symptoms.
2.2 Conventional treatment for a significantly diseased aortic valve is surgical replacement with an artificial (biological or mechanical) prosthesis, or transcatheter aortic valve implantation (TAVI) with a biological prosthesis. Bioprosthetic and mechanical valves do not perform as well as valves made from the person's own tissue. Their durability is also limited (although mechanical valves last longer than bioprosthetic valves), which may be an issue for younger people. People with mechanical valves need lifelong anticoagulation. This increases the risk of haemorrhagic complications, particularly for older people, and anyone with significant comorbidities or who wants to become pregnant. Aortic regurgitation can be treated by repairing the aortic valve with patches instead of replacing it.
2.3 Aortic valve reconstruction using glutaraldehyde-treated autologous pericardium is suitable for:
people who cannot or do not want to take anticoagulation
people with an aorta too narrow for a standard prosthetic valve
young people who want to avoid long-term anticoagulation.
2.4 Under general anaesthesia, the heart is accessed using a full or partial sternotomy, and the person is established on cardiopulmonary bypass. The heart is stopped with cardioplegic arrest. A section of the pericardium is removed and excess adipose tissue removed. The section of pericardium is treated with glutaraldehyde and rinsed with saline to avoid drying. The aorta is opened, the valve is inspected and the diseased valve cusps carefully removed. The intercommissural distances are measured using Ozaki sizers, and the treated pericardium is trimmed to the desired size and stitched to the aortic annulus to replace the removed valve leaflet(s). When aligned, the leaflets are stitched to the wall of the aorta to create a functional valve. The aorta is closed, the heart is de-aired and cardiopulmonary bypass is stopped. The circulation is restored and the chest is closed. The function of the valve is assessed intraoperatively by transoesophageal echocardiography.