A Survey of Antibiotic Use During Insertion of Cardiovascular Implantable Devices Among United States Implanters.

Antibiotic use for cardiovascular implantable devices (CIED) prophylaxis is well-accepted despite a paucity of data. Pre-procedural prophylaxis lowers the rate of CIED infections; however, data is lacking for intra- or post-procedural antibiotic use. Antibiotic-eluting envelopes (ENVELOPE) [TYRX®TM] have been shown to reduce post-procedural infections. Understanding implanter practices may provide insight as to the need for antibiotic stewardship. The purpose of this survey was to assess the practices of implanters nationally. A survey was completed by 150 implanters across the US. Participants were board certificated, implanters of CIEDs, with varying experience (1-25 years), in various hospital settings. Of the respondents, 97% reported routine use of systemic antibiotics pre-operatively. About two-thirds of implanters continue systemic antibiotics post-operatively, with half continuing antibiotics for >24 h; 83% of implanters add antibiotic to saline for the purpose of irrigating the wound; 55% routinely use ENVELOPE on approximately 38% of patients. Common reasons cited for ENVELOPE use were infection concerns, significant risk factors, prior device infection, and immunosuppressed status. Two-thirds of respondents use systemic antibiotics during generator changes, with >50% continuing antibiotics for >24 h. This study suggests wide variations in practice among implanters. Additional attention to existing guidelines and evidence regarding appropriate use of ENVELOPE is still needed.

Complete Atrioventricular Block: A Rare Complication of MitraClip Implantation.

MitraClip (Abbott Vascular, Inc., Santa Clara, California) has emerged as a viable alternative for treatment of symptomatic severe mitral regurgitation. Conduction abnormalities are not a known complication of this procedure. We report a case of complete heart block without a ventricular escape rhythm immediately following MitraClip placement near the medial leaflets (A3-P3) in a patient with underlying trifascicular block. (Level of Difficulty: Intermediate.).

First layer compression and transition to standing second layer of terephthalic acid on Cu(100).

Terephthalic acid on metal surfaces is a system of high interest for interfacial layers as well as for use in generating surface nanostructures by supramolecular self-assembly. Here we demonstrate structural transitions upon compression of the first layer as well as a significant transition from a flat lying chemisorbed first monolayer to a standing second layer. The second layer structure is stable at 150 °C, but a weakly bound state is observed to desorb molecularly below that temperature, likely a transient mobile state during annealing. Molecular resolution scanning tunnelling microscopy is complemented by X-ray photoelectron spectroscopy and thermal desorption spectroscopy in this study. These results provide general insight in the development of self-assembled organic thin films at surfaces, especially with regard to the nature of the metal/organic interface and growth transitions to maximize first layer packing and obtain a second layer that bridges commensurability with the substrate and a more bulk-like structure.

Adsorption and bonding of first layer and bilayer terephthalic acid on the Cu(100) surface by high-resolution electron energy loss spectroscopy.

The self-assembled and highly ordered first layer of terephthalic acid on Cu(100) as well as its bilayer on the same surface are studied here using high-resolution electron energy loss spectroscopy (HREELS), Auger electron spectroscopy, and low energy electron diffraction. These experiments show completion of the first layer before growth of the second layer. HREELS measurements show that the first layer of the acid deprotonates, which is seen in the absence of the OH stretching mode for the acid groups. However, this mode is present in the bilayer structure, confirming that the deprotonation is due to a reaction with the Cu surface and suggesting that there is little mixing of the layers. It has been suggested previously that the TPA monolayer structure is stabilized by an intermolecular hydrogen bonding interaction, but we are not able to resolve any distortion of the CH stretching mode for such an interaction, but instead see evidence for direct bonding to the Cu surface.