A computed tomography algorithm for crossing coronary chronic total occlusions: riding on the wave of the proximal cap and distal vessel segment.

With wider adoption of coronary computed tomography angiography (coronary CTA), chronic total occlusions (CTOs) are being increasingly identified and characterised by non-invasive angiography. In particular, the ability of coronary CTA to clearly delineate atherosclerotic plaque, as well as to display three-dimensional vessel trajectories, has garnered particular attention in the context of preprocedural planning and periprocedural guidance of CTO percutaneous coronary intervention (PCI). Single CTO features and combined scoring systems derived from CTA (mostly exceeding the diagnostic performance of the angiographic J­CTO score) have been used to predict time-efficient guidewire crossing, and thus grade the CTO difficulty level prior to PCI. In addition, the introduction of three-dimensional CTA/fluoroscopy co-registration for periprocedural navigation during CTO PCI offers the unprecedented opportunity to resolve proximal cap ambiguity and clearly visualise the distal CTO segment, thereby potentially influencing CTO PCI strategies and techniques. In this review, the potential advantages of non-invasive evaluation of CTO by coronary CTA are described, and a CTA-based hybrid algorithm is introduced for further enhancing the efficiency of CTO PCI. Further studies are clearly needed to verify the proposed approach. However, several luminary operators have already implemented coronary CTA for planning and periprocedural guidance of CTO interventions using the hybrid algorithm.

The eating-related behaviours, disorders and expectations of candidates for bariatric surgery.

It is important that clinicians and researchers understand the possible eating-related difficulties experienced by pre-bariatric surgery candidates, as well as their expectations of how their eating and hunger will change after surgery. This review examines English-language publications related to the eating-related behaviours, disorders and expectations of bariatric candidates. Seventy-five articles related to binge eating disorder, grazing, night eating syndrome, emotional eating, food cravings and addiction, and pre-surgical expectations of post-surgical eating in this population were critically reviewed. A variety of often problematic eating behaviours appear more common in bariatric candidates than in non-obese populations. The literature suggests that 4-45% of candidates may have binge eating disorder, 20-60% may graze, 2-42% may have night eating syndrome, 38-59% may engage in emotional eating and 17-54% may fit criteria for food addiction. Binge eating may also be more prevalent in bariatric candidates than in similarly obese non-surgical individuals. Expectations of surgery are high, with pre-surgical candidates believing their bariatric procedure will virtually guarantee significantly improved eating behaviours. Study replications are needed, and further investigation into prevalence, impacts and candidate characteristics related to disordered eating behaviours, as well as candidates' expectations of eating after surgery, will be important. Further comparisons of bariatric candidates to similarly obese non-bariatric populations will be important to understand eating-related characteristics of candidates beyond those related to their weight. Future research may be improved by the use of validated measures, replicable methodologies, minimization of data collected in circumstances where respondents may been motivated to 'fake good', use of prospective data and consistent definitions of key terminology.

Transgene delivery of plasmid DNA to smooth muscle cells and macrophages from a biostable polymer-coated stent.

Metallic stents coated with a polyurethane emulsion containing plasmid DNA were implanted in rabbit iliac arteries to evaluate transgene delivery and expression in the vessel wall. The expression of the plasmid-encoded marker genes, beta-galactosidase, luciferase and green fluorescence protein (GFP), were evaluated at 7 days after implantation. In all cases, plasmid transfer was confined to the vessel wall at the site of stent implantation, plasmid DNA was not observed in vessel segments immediately proximal or distal to the stent and dissemination of plasmid DNA to lung, liver or spleen was not observed. Expression of transgenes occurred only in vessel segments in contact with the stent and analysis of the GFP expression pattern revealed a high frequency of marker protein-positive cells occurring at or near the luminal surface. The extent of transgene expression was dependent upon the quantity of DNA loaded onto the stent and no signal was detected in vessel segments that received polymer-coated stents lacking plasmid DNA. Of significance, colocalization studies identified transgene expression not only in vascular smooth muscle cells but also in macrophages. Hence, polymer-coated stents provide a new capability for transgene delivery to immune cells that are believed to contribute to the development of in-stent restenosis.