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The complex nature of congenital heart disease (CHD) has hindered the establishment of management standards for peri-catheterization anticoagulation. We sought to describe anticoagulation practice variability among providers performing cardiac catheterization in children and adults with CHD. A web-based survey (http://www.surveymonkey.com) was distributed to pediatric and congenital interventional cardiologists. Respondents were queried on their training, practice setting, years in practice, and case volume. Clinical questions focused on general anticoagulation strategies and on five common clinical scenarios: two diagnostic (biventricular circulation, single ventricle physiology) and three interventional cardiac catheterizations (atrial septal defect closure, pulmonary artery stenting in Fontan circulation, stent placement for coarctation of aorta). Seventy-seven pediatric and congenital interventional cardiologists responded to the survey (81% in the United States). Twenty-six (36%) worked in a public medical institution; 57% worked in a free-standing children's hospital. Twenty-six percent had been in practice for < 5 years and 32% for > 15 years; 75% completed additional training in interventional congenital cardiology. The median number of cases performed was 200/year (IQR 110); median number of interventional cases was 100/year (IQR 100). Responses to general queries and specific clinical scenarios suggested significant variation in anticoagulation practices, including monitoring of anticoagulation during catheterization, protamine use, and outpatient anticoagulation after catheterization. Practices not only varied between providers but also between different clinical scenarios. Practice patterns did not correlate with provider experience or case volume. Management of anticoagulation in the congenital cardiac catheterization lab varies from operator to operator. Our study may provide some initial insight and context for discussion regarding anticoagulation in a field of increasingly heterogeneous interventional techniques and patient substrates. Future studies would be helpful to better define "best practices" for peri-procedural thromboprophylaxis in patients with congenital heart disease. [ABSTRACT FROM AUTHOR]

Abstract: Background: Although polytetrafluoroethylene (PTFE) is now used as a covering in a wide variety of vascular stents, little is known about the resultant pathologic and angiographic changes in the arterial and venous system after stent deployment. Methods: Atrium PTFE-covered stents were deployed in the abdominal aorta and the inferior vena cava (IVC) of two Yorkshire pigs. Angiograms were performed after deployment and at recatheterization. A complete histopathological exam was performed after sacrifice, and angiographic and histology findings were then compared between the two types of blood vessels. Results: The arterial stents demonstrated no stenosis on angiography and minimal in-stent intimal proliferation by histopathology. A uniform layer of neointima coated the inside of the stent by 1 month with no obvious thrombus formation. In contrast, the venous stents demonstrated angiographic evidence of significant in-stent stenosis of variable degrees and the histology showed increased intimal hyperplasia with fibrin deposition. PTFE from both the arterial and venous stents had variable amounts of tissue ingrowth with cells observed to be growing into and through the PTFE fibers. Conclusions: Atrium PTFE-covered stents have excellent short-term angiography and histopathology in the arterial system, while stents in the venous system developed rapid in-stent intimal hyperplasia. PTFE fibers from both types of vasculature permitted cells to grow through and within them. [Copyright &y& Elsevier]

We report the case of a 17-month-old female with tick paralysis presenting to an urban Los Angeles emergency department. The tick was later identified as the North American wood tick, Dermacentor andersoni, and was likely obtained while the family was vacationing on a dude ranch in Montana. We discuss the epidemiology of tick paralysis, a differential diagnosis for health care providers, and methods of detection and removal. Given the increasing popularity of outdoor activities and ease of travel, tick paralysis should be considered in cases of acute or subacute weakness, even in an urban setting. [Copyright &y& Elsevier]

Balloon-expandable stents, implanted in infants and children with congenital heart disease (CHD), often require redilation to match somatic growth. Small diameter stents may eventually require longitudinal surgical transection to prevent iatrogenic vascular stenosis. Intentional transcatheter stent fracture (TSF) is an emerging alternative approach to stent transection, but little is known about the optimal stent substrate and best protocol to improve the likelihood of successful TSF. Bench testing was performed with a stent dilation protocol. After recording baseline characteristics, stents were serially or directly dilated using ultra-high-pressure balloons (UHPB) until fracture occurred or further stent dilation was not possible. Stent characteristics recorded were as follows: cell design, metallurgy, mechanism, and uniformity of fracture. Stents tested included bare-metal coronary stents, premounted small diameter stents, and ePTFE-covered small diameter premounted stents. Ninety-four stents representing 9 distinct models were maximally dilated, with 80 (85%) demonstrating evidence of fracture. Comprehensive fracture details were recorded in 64 stents: linear and complete in 34/64 stents (53.1%), linear and incomplete in 9/64 stents (14.1%), transverse/complex and complete in 6/64 stents (9.4%), and transverse/complex and incomplete in 15/64 stents (23.4%). Stent fracture was not accomplished in some stent models secondary to significant shortening, i.e., 'napkin-ring' formation. Serial dilation resulted in evidence of fracture in 62/67 (92.5%) stents compared with 18/27 (66.7%) stents in the direct dilation group ( p = 0.003). Intentional TSF is feasible in an ex vivo model. Serial dilation more reliably expanded the stent and allowed for ultimate stent fracture, whereas direct large diameter dilation of stents was more likely to generate a 'napkin-ring' configuration, which may be more resistant to fracture. In vivo animal and human testing is necessary to better understand the response to attempted TSF for newly developed stents as well as those currently in use. [ABSTRACT FROM AUTHOR]