the coronary sinus. Some surgeons also opt to place a vent in the left ventricle through the right superior pulmonary vein, because this helps to prevent left ventricular distention before and after cardiac arrest. When the set-up is ready, the aorta is clamped shut with a cross-clamp to stop blood pumping through the heart and cardioplegia is infused. The surgeon incises the aorta a few milometers above the sinotubular junction (just above the coronary ostia, where the coronary arteries join the aorta) – a process known as aortotomy. After this, cardioplegia is delivered directly through the ostia. The heart is now still and the surgeon removes the patient's diseased aortic valve. The cusps of the aortic valve are excised, and calcium is removed (debrided) from the aortic annulus. The surgeon measures the size of the aortic annulus and fits a mechanical or tissue valve of the appropriate size. Usually the valve is fixed in place with sutures, although some sutureless valves are available. If the patient's aortic root is very small, the sutures are placed outside of the aortic root instead of at the annulus, to gain some extra space. Once the valve is in place and the aorta has been closed, patient is placed in a Trendelenburg position and the heart is de-aired and restarted. The patient is taken off the cardiopulmonary bypass machine. Transesophageal echocardiogram (an ultrasound of the heart done through the esophagus) can be used to verify that the new valve is functioning properly. Pacing wires are usually put in place, so that the heart can be manually controlled should any complications arise after surgery. Drainage tubes are also inserted, to drain fluids from the chest. These are usually removed within 36 hours, while the pacing wires are generally left in place until right before the patient is discharged from the hospital. Hospital stay and recovery time After surgical aortic valve replacement, the patient will usually stay in an intensive care unit for 12–36 hours. Unless complications arise, the patient is then able to go home after approximately four to seven days. Common complications include disturbances to the heart's rhythm (heart block), which typically require the permanent insertion of a cardiac pacemaker. Recovery from aortic valve replacement takes about three months if the patient is in good health. Patients are advised not to lift anything heavier than 10 lbs for several weeks, and not to do