ABSTRACT
Coronary surgery performed on an arrested heart, using one internal mammary artery and a saphenous vein carries two main potential drawbacks: the known failure rate of vein grafts and the relatively high rate of neurologic injury. To address these concerns, we describe a technique that achieves complete revascularization without manipulating the ascending aorta (anaortic, off-pump) and utilizing total arterial grafts. All patients undergo thorough preoperative investigation, including bilateral carotid, vertebral and subclavian artery Duplex ultrasounds. A pulmonary artery catheter, transoesophageal echocardiography, and point-of-care coagulation testing are used in each case. The left and right internal mammary arteries and non-dominant radial artery are harvested using a fully skeletonised technique. Wide bilateral extrapleural retrothymic tunnels are developed and the pericardium is opened widely to facilitate cardiac positioning. A tandem graft is constructed with the right internal mammary artery (RIMA) in situ and radial artery using an end-to-end anastomosis. This graft is brought into the pericardium and through the transverse sinus in order to graft the lateral and inferior walls with multiple sequential distal anastomoses. The left internal mammary artery (LIMA) in situ is used to graft the anterior wall. Four main cardiac positions (high and low lateral walls, inferior and anterior walls) are obtained using a combination of off-pump stabilizer positioning, alternate tension on pericardial 'heart-strings', table tilting and folded wet sponges. All distal anastomoses are performed using silastic intracoronary shunts and an off-pump myocardial stabilizer. All grafts are checked using transit-flow time measurements. Milrinone is continued overnight and dual antiplatelet therapy is continued for 3 months postoperatively.
ABSTRACT
The choice of a bioprosthetic valve (BV) or mechanical valve (MV) in middle-aged adults undergoing aortic valve replacement is a complex decision that must account for numerous prosthesis and patient factors. A systematic review and meta-analysis was performed to compare long-term survival, major adverse prosthesis-related events, anticoagulant-related events, major bleeding, reoperation, and structural valve degeneration in middle-aged patients receiving a BV or MV. A comprehensive search from six electronic databases was performed from their inception to February 2016. Results from patients aged less than 70 years undergoing aortic valve replacement with a BV or MV were included. There were 12 studies involving 8,661 patients. Baseline characteristics were similar. There was no significant difference in long-term survival among patients aged 50 to 70 or 60 to 70 years. Compared with MVs, BVs had significantly fewer long-term anticoagulant-related events (hazard ratio [HR] 0.54, p = 0.006) and bleeding (HR 0.48, p < 0.00001) but significantly greater major adverse prosthesis-related events (HR 1.82, p = 0.02), including reoperation (HR 2.19, p < 0.00001). The present meta-analysis found no significant difference in survival between BVs and MVs in patients aged 50 to 70 or 60 to 70 years. Compared with MVs, BVs have reduced risk of major bleeding and anticoagulant-related events but increased risk of structural valve degeneration and reoperation. However, the mortality consequences of reoperation appear lower than that of major bleeding, and recent advances may further lower the reoperation rate for BV. Therefore, this review supports the current trend of using BVs in patients more than 60 years of age.
