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Background: Antithrombogenicity of extracorporeal membrane oxygenation (ECMO) devices, particularly oxygenators, is a current problem, with numerous studies and developments underway. However, there has been limited progress in developing methods to accurately compare the antithrombogenicity of oxygenators. Animal experiments are commonly conducted to evaluate the antithrombogenicity of devices; however, it is challenging to maintain a steady experimental environment. We propose an innovative experimental animal model to evaluate different devices in a constant experimental environment in real‐time. Methods: This model uses two venous–arterial ECMO circuits attached to one animal (one by jugular vein and carotid artery, one by femoral vein and artery) and real‐time assessment of thrombus formation in the oxygenator by indocyanine green (ICG) fluorescence imaging. Comparison studies were conducted using three pigs: one to compare different oxygenators (MERA vs. CAPIOX) (Case 1), and two to compare antithrombotic properties of the oxygenator (QUADROX) when used under different hydrodynamic conditions (continuous flow vs. pulsatile flow) (Cases 2 and 3). Results: Thrombi, visualized using ICG imaging, appeared as black dots on a white background in each oxygenator. In Case 1, differences in the site of thrombus formation and rate of thrombus growth were observed in real‐time in two oxygenators. In Case 2 and 3, the thrombus region was smaller in pulsatile than in continuous conditions. Conclusions: We devised an innovative experimental animal model for comparison of antithrombogenicity in ECMO circuits. This model enabled simultaneous evaluation of two different ECMO circuits under the same biological conditions and reduced the number of sacrificed experimental animals. [ABSTRACT FROM AUTHOR]

Objective: Saphenous vein grafts (SVGs) are widely used as bypass conduits in coronary artery bypass grafting. Compared with the conventional technique, the "no-touch" technique, wherein the saphenous veins are harvested with the surrounding tissue, may improve SVG patency; however, there are concerns regarding wound complications. To address this issue, we describe our novel no-touch technique with separate skin incisions using a long-shafted ultrasonic scalpel and report the clinical outcomes., Methods: We enrolled 66 male patients who underwent isolated coronary artery bypass grafting between April 2016 and April 2021. There were 30 and 36 patients treated using our no-touch technique and the conventional technique, respectively. The participants underwent coronary angiography before discharge and were followed clinically. SVG samples were taken for pathological examination., Results: SVGs harvested using our no-touch technique displayed preservation of the vessel wall structure and surrounding tissues. Our no-touch technique demonstrated no inferiority in patency compared with the conventional technique, and there was no SVG occlusion in the no-touch group. The frequency of leg wound complications was higher in the no-touch group than the conventional group, but no surgical site infections and severe complications occurred in the no-touch group., Conclusions: SVGs harvested using our novel no-touch technique had similar pathological characteristics to those harvested using the original no-touch technique reported previously. Our no-touch technique maintained SVG patency and caused no severe wound complications. However, a large-scale, longitudinal study is required to accurately assess the clinical outcomes of our no-touch technique.