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HbO 2 concentrations could be explained by a compensatory arterial dilation.We demonstrate that multichannel optical topographic analysis can provide information on regional cerebral hemodynamics and oxygenation in patients supported by ECMO. Simultaneous measurement of systemic and cerebral HbO 2 and HHb concentrations can help elucidate mechanisms related to the response of the brain during changes in ECMO and cardiopulmonary bypass flows.In this patient modest changes in ECMO flows appear to present a significant hemodynamic challenge to cerebral circulation. Further work is necessary to support application of this novel brain-monitoring technology in cardiac theaters and intensive care units, and we now have a protocol to further investigate regional brain oxygenation in these patients. References1. Nollert G, Shin'oka T, Jonas RA. Near infrared spectrophotometry of the brain in cardiovascular surgery.

OBJECTIVES The aim of this study was to elucidate the remodelling of the internal mammary artery (IMA)–left anterior descending artery anastomosis and compare 2 different anastomosis techniques (end-to-side versus side-to-side) using computational fluid dynamics. METHODS This study included 9 patients. Computed tomography (CT) angiography was performed immediately after coronary artery bypass grafting (CABG) and at 3–6 months later. The computational fluid dynamics models were made using the CT data. The pulsatile 3-dimensional blood flow was achieved with the finite volume method to evaluate the postoperative morphological and haemodynamic changes at the anastomosis in each patient. Flow velocity distribution, wall shear stress (WSS) and its fluctuation oscillatory shear index were measured. RESULTS No early or mid-term graft occlusion was observed in the study series. In the side-to-side anastomosis, pouch formation at the distal end of IMA caused a vortex flow with low WSS immediately after CABG. However, at 3–6 months after surgery, this pouch disappeared. As a result, the laminar straight flow with uniform WSS distribution was achieved inside the anastomosis. In the end-to-side anastomosis, the anastomosis shape was remodelled, resulting in a laminar flow pattern with uniform WSS distribution. A patchy high oscillatory shear index was detected at the IMA wall on the top of anastomosis in either anastomosis techniques immediately after the surgery, but it disappeared at 3–6 months after surgery. CONCLUSIONS Regardless of the anastomosis technique used, a successful remodelling of the IMA–left anterior descending artery anastomosis shape was achieved a few months after surgery, resulting in a straightforward flow streamline, with uniform WSS distribution and minimal oscillatory shear index.

A 75-year-old woman was referred to our hospital for dyspnea and edema of the lower limbs. Computed tomography angiography revealed a dilated left coronary artery from the left main trunk to the left circumflex branch and a dilated fistula originating from the left circumflex branch and draining into the persistent left superior vena cava. Physical examination revealed pulmonary hypertension and congestive heart failure. We performed closure of the fistula and left main coronary artery orifice and coronary artery bypass grafting.