The approach can be a standard sternotomy or a mini sternotomy incision. The ascending aorta should be cannulated as distally as possible, at or above the pericardial aortic reflection, so as to maximise the space available for subsequent placement of the aortic cross-clamp as well as the aortotomy. A single two-stage venous cannula is placed into the right atrium. Cardiopulmonary bypass is commenced. To optimise visualisation during the operation, a vent may be placed through the right superior pulmonary vein via the left atrium and into the left ventricle. The aortic cross-clamp is applied as close to the aortic cannula as possible. In the absence of significant aortic regurgitation, antegrade cardioplegia may be delivered to arrest the heart prior to aortotomy. Retrograde cardioplegia can also be delivered if desired for continued myocardial protection. This may also be helpful in cases of aortic regurgitation.

The annulus is sized using valve obturators of the desired valve prosthesis. The valve should fit snugly onto the aortic annulus. Too loose a fit would suggest that the patient could benefit from a larger sized prosthesis while too tight a fit would make seating the prosthesis difficult and also risk disruption of the aortic annulus and closure of the aortotomy. In small aortic roots or where patient-prosthesis mismatch may occur, for example, in a large patient with a small aortic root, patch enlargement of the aortic root may be necessary, using either an anterior (Nick’s/Nunez, Manouguian procedure) or a posterior (Konno/Rastan) approach.