Aortic Valve Replacement : Technique: Surgical technique is not much different from what has already been described for aortic stenosis. Care must be taken to avoid VF soon after connecting the patient to cardio pulmonary bypass. Because of free aortic regurgitation, fibrillating heart will distend and produce myocardial damage. To avoid fibrillation, cooling is not started until the surgeon is ready to cross clamp the aorta, open it and administer cardioplegia.
The presence of aorlic regurgitation means that cardioplegia cannot be administered lo the aortic root. For antegrade cardioplegia, aorta has to be opened and by special hand held cannula it has to be administered. A hypertrophied and dilated heart will require excess amount of cardioplegic solution. For better protection retrograde coronary sinus cardioplegia is also given.
When a patient requires mitral valve replacement also, that is done first. Then repeat assessment of the aortic annulus is done to choose the correct sized valve. Bioprosthetic valves come stented. The effective area (EOA) is much less in stented prosthesis. In the stentless group a commonly used variety is a porcine one - Toronto SPV (stentless prosthetic valve). This valve is inserted by 2 rows of sutures as is usually done for a homograft.