Sinoatrial nodal artery posterior aspect of the interatrial septum. The origin of the sinoatrial node artery is not related to coronary artery dominance, which means the side (right or left) that provides the circulation to the back of the heart. In contrast, the atrioventricular nodal branch, that is the artery that brings blood to the atrioventricular node, depends on coronary artery dominance. The sinoatrial node surrounds the sinoatrial artery, which can run centrally (in 70% of individuals) or off center within the node. A left S-shaped sinoatrial artery, originating from the proximal left circumflex or LCx artery, has been described as a common
Node 4 Node 4 Node 4, also known as the Docking Hub System (DHS), is a proposed module of the International Space Station (ISS). As of 2011 NASA was considering a 40-month design and development effort for Node 4 that would result in its launch in late 2013. Node 4 would be built using the Node Structural Test Article (STA) and docked to the forward port of the Harmony module. The Structural Test Article was built to facilitate testing of ISS hardware and was intended to become Node 1. However, during construction, structural design flaws were discovered. The under-construction Node 2 was