Device-related infection is the result of the interaction between the device, the microbe, and the host. Initial attach- ment of bacteria to the device is mediated by physical- chemical properties, such as hydrophobicity, surface tension, and electrostatic charge, of the plastic surface of the device and the bacterial surface.50 Bacteria, particularly Gram- positive cocci, can also adhere to and be engulfed by endothelial cells that can cover an endothelialized lead over a period of time, which is thought to be an important mecha- nism of device infection by the hematogenous route. Device Factors Device-related factors, such as the type of plastic polymer, irregularity of its surface, and its shape, can affect bacterial adherence to the device.51 Plastic polymers that encase medical devices, as well as the pathogens that adhere to them, are hydrophobic. The greater the degree of hydrophobicity, the greater is the adherence.52 Polyvinyl chloride favors more adherence than Teflon (duPont, Wilmington, Del), polyeth- ylene more than polyurethane, silicone more than polytetra- fluoroethylene, and latex more than silicone; some metals (eg, stainless steel) favor adherence more than others (eg, titanium). An irregular surface of the device favors microbial adherence more than a smooth surface. Indirect device factors previously addressed in this document as risk factors associ- ated with CIED infection include subsequent invasive manip- ulation of an implanted CIED and a limited number of device implantations previously performed by the physician per- forming the procedure. Microbial Factors None of the major virulence factors or toxins of S aureus have been found in CoNS, and it seems clear that the development and persistence of CoNS infections, which are so often associated with foreign materials, are due to different mech- anisms, such as adherence. 