421 - Aortic Valve Replacements

W H I C H T Y P E O F V A L V E I S B E T T E R ? The indications for using a tissue valve over a mechanical valve ultimately depends on the patient. The American Heart Association and American College of Cardiology recommend tissue valves for patients 70 years of age or older and mechanical valves for patients younger than 60 years of age. 10 Based on randomized trials, patient survival is the same up to 15 years post-operation in both mechanical and tissue valves, based on randomized trials. There is also no signifi- cant difference in stroke occur- rences between the two types of valves. 14 Mechanical valves, how- ever, show more mid-term mor- bidity than tissue valves due to blood clots. 10 In a retrospective study of 4,253 patients aged 50 to 69 from the years 1997 to 2004, 58 major bleeding events were recorded in patients with tissue valves, and 101 major bleeding events in patients with mechani- cal valves. 14 Mechanical valves require patients to continuously take blood thinners; therefore, mechanical valves are recom- mended for patients who can take or are already taking blood thinners. 11 Patients who have tis- sue valves do not need to take blood thinners, so a tissue valve is ideal for patients who cannot or do not want to be on blood thin- ners. 11 This is a consideration for a middle-aged patient who has an active lifestyle as being on blood thinners during the prime of one’s life can restrict or inhibit the patient’s lifestyle, especially if they are particularly active. If a patient would need a reoperation at some point, it may be necessary with a tissue valve. The St. Jude Medical Trifecta Valve, made with bovine peridardium, can last 8 to 20 years. 12 In older patients this may not be an issue; however, in younger patients, it is something to consider. According to the retrospective study previously men- tioned, in a follow-up time of 16.9 years, 79 patients with tissue valves required reoperation, while only 43 patients with mechanical valves required a second operation. 14 An aortic valve replacement is a good option for peo- ple with aortic regurgitation and/or aortic stenosis. A tissue valve may be ideal for an older patient who will not out- live the valve, but it also may be ideal for a younger, active, healthy patient, due to their likelihood of not needing blood thinners. A mechanical valve also would be better suited for a younger patient who takes blood thinners and not at risk for falls. The type of valve used depends on the patient’s age, health condition, lifestyle and surgeon recommendation. T H E P R O C E D U R E The patient is positioned onto the operating room (OR) table with the help of the OR staff. The OR staff uses the appropriate padding on the patient’s arms and uses a sheet to tuck the arms at the patient’s side. The circulator places the appropriate monitors on the patient. The anesthesiol- ogist inserts a radial arterial pressure line to monitor the patient’s blood pressure in real time and administers general anesthesia. The circulator will insert a Foley catheter while the anesthesiologist places a central line. Prior to perform- ing a scrub, the surgeon marks the incision site, and a time out is called to verify correct patient identity, correct surgi- cal site and procedure to be performed. The anesthesiolo- gist will perform a transesophageal echocardiogram (TEE) JANUARY 2019 | The Surgical Technologist | 15 Pulmonary veins Left atrium Pulmonary valve Aortic valve Right atrium Tricuspid valve