U. Allahwala

Clinical utility of optical coherence tomography (OCT) in the optimisation of Absorb bioresorbable vascular scaffold deployment during percutaneous coronary intervention.

AIMS The Absorb everolimus-eluting bioresorbable vascular scaffold (BVS) represents an important advance in percutaneous coronary intervention (PCI) technology. With increasing use of BVS, it is important to understand its expansion characteristics to ensure optimal scaffold deployment. Optical coherence tomography (OCT) has been shown to improve detection of intraprocedural complications compared with conventional intravascular imaging modalities. This study aimed to determine whether or not OCT, post successful angiographic BVS implantation, influenced decision making with regard to the need for further scaffold optimisation. METHODS AND RESULTS Consecutive patients undergoing OCT-guided BVS implantation from August 2012 to March 2013 were reviewed to determine if further intervention was required to optimise BVS implantation, based on OCT performed after what was deemed to be an optimal angiographic result. Nineteen patients with 29 scaffolds were analysed. Mean age was 53.7, with 84% male. There was a range of lesion types with 12 (63%) type A and seven (37%) type B or C. Of 29 scaffolds analysed, 28% required further intervention after OCT review, three (37.5%) due to scaffold malapposition and five (62.5%) due to scaffold underexpansion. CONCLUSIONS Despite achieving angiographic success in all BVS implantations, further optimisation was required in over a quarter of patients on the basis of OCT findings.

Wikipedia use amongst medical students - new insights into the digital revolution.

Web2.0 resources are internet-based tools, such as ‘wikis’ and social networking sites, allowing users to actively participate in the creation and editing of information. Wikipedia is increasingly being used by medical students and physicians when actively searching for health information (Judd & Kennedy 2010). While the paucity of formal editorial review of such resources warrants scepticism, there is increasing evidence about its reliability and potential use (Rajagopalan et al. 2011). We sought to determine the prevalence of Wikipedia use amongst medical students at one institution, through a selfadministered 12-item online questionnaire. A total of 361 students participated in the study across six years of the course. The mean participant age was 21 with a non-significant over-representation of females (57%). Wikipedia was used by 341 students (94%) while studying medicine. The most common reasons reported for using Wikipedia were ease of access (98%) and ease of understanding (95%). A lack of confidence in performing literature reviews was cited by 10% of the respondents. In those students who did not use Wikipedia, 85% reported it as an unreliable resource. There was no significant correlation between the year of medical school and the use of Wikipedia (R1⁄4 0.67, p1⁄4 0.12). However, there was a significant correlation between the year of medical school and the use of Wikipedia as the first resource (R1⁄4 0.81, p5 0.02), with older years less likely to use Wikipedia as the initial resource. Similarly, there was an inverse correlation between the year of medical school and the use of Wikipedia as the only resource (R1⁄4 0.70, p5 0.05), as the most common resource (R1⁄4 0.67, p5 0.05) and its perceived reliability (R1⁄4 0.73, p5 0.05). Multivariate regression analysis models found the year of medical school to be an independent predictor of the use of Wikipedia as the first resource (p5 0.05), only resource (p5 0.005) and most common resource (p5 0.05). The use of Wikipedia is almost ubiquitous throughout medical school for medical education. The ease of access and understanding, as well as readily usable and consumer-friendly interfaces, means students often turn to this, rather than traditional authoritative resources. While the reliance on Wikipedia reduces throughout medical school, this is likely due to confidence and ability to concurrently use other resources as well as perceived reduced reliability. Medical school administrators would benefit from embracing and developing web2.0 resources and include their use in ongoing dynamic medical education.

The effect of coronary artery plaque composition, morphology and burden on Absorb bioresorbable vascular scaffold expansion and eccentricity — A detailed analysis with optical coherence tomography

AIMS Suboptimal stent expansion correlates with adverse cardiac events. There is limited information regarding Absorb bioresorbable vascular scaffold (BVS) expansion characteristics. Optical coherence tomography (OCT) allows for high-resolution assessment of plaque morphology, composition and assessment of BVS expansion. This study evaluates coronary plaque composition, morphology and burden and their effect on Absorb BVS expansion using OCT. METHODS AND RESULTS Two thousand three hundred and thirty four frames totalling 462.6 mm of BVS from twenty OCT-guided BVS implantations were examined. 200 μm longitudinal cross-sections of each BVS were analysed for lumen contours and plaque characteristics. The relationship between each plaque characteristic and scaffold expansion index (SEI) or scaffold eccentricity index (SEC) was analysed by repeated measures ANOVA. Forty-four fibrous and 265 calcific plaques were identified. Lower SEI was significantly (p<0.001) associated with greater calcific plaque (CP) area (mean SEI 78.9% vs. 80.0%), thickness (78.5% vs. 80.4%) and lower CP depth (78.3% vs. 80.2%). Lower SEC was significantly (p<0.001) associated with greater fibrous plaque (FP) area (0.84 vs. 0.85), thickness (0.83 vs. 0.86), arc angle (0.84 vs. 0.85), greater CP area (0.83 vs. 0.86), CP thickness (0.83 vs. 0.86), CP angle (0.84 vs. 0.85) and lower CP depth (0.84 vs. 0.85). Greater FP area was associated with greater SEI (81.0% vs. 80.0%, p<0.001), even after adjustment for target vessel size. Greater FP angle (80.7% vs 78.3%, p<0.001) and quadrants occupied were also associated (80.0% vs 78.5%, p<0.002) with greater SEI. CONCLUSION BVS expansion and eccentricity are significantly impacted by plaque composition, morphology and burden.

Transcatheter aortic valve implantation: current trends and future directions

Transcatheter aortic valve implantation (TAVI) has been increasingly utilized for the treatment of severe symptomatic aortic stenosis in inoperable and high surgical risk patients. Recent advances in valve technology include repositionable scaffolds and smaller delivery systems, as well as improvement in periprocedural imaging. These advances have resulted in reduction of vascular complications, rates of paravalvular aortic regurgitation and periprocedural stroke and improved overall outcomes. Increasingly, TAVI is the preferred treatment for high-risk surgical patients with severe aortic stenosis. Consequently, there is growing interest for the use of TAVI in lower surgical risk patients. Furthermore, the role of TAVI has expanded to include valve-in-valve procedures for the treatment of degenerative bioprosthetic valves and bicuspid aortic valves. Questions remain in regard to the optimal management of concurrent coronary artery disease, strategies to minimize valve leaflet restriction and treatment of conduction abnormalities as well as identifying newer indications for its use.

Comparison of two dimensional quantitative coronary angiography (2D-QCA) with optical coherence tomography (OCT) in the assessment of coronary artery lesion dimensions

Objectives There is limited data on how well 2D-QCA and OCT agree with each other for measurement of coronary artery lumen dimensions. We aimed to assess the agreement between the two modalities. Methods Patients undergoing OCT for assessment of coronary artery lesions were reviewed. Minimum luminal diameter (MLD), proximal reference diameter and distal reference diameter were measured for each lesion prior to stenting. Results OCT was performed in 64 patients and 40 lesions were suitable for analysis. There was a good correlation for proximal and distal reference diameters (r = 0.86, p < 0.0001 and r = 0.92, p < 0.0001 respectively). There was good agreement on Bland–Altman analysis; the proximal and distal reference diameters measured by QCA were on average 0.09 mm (95% CI, − 0.52 to 0.53 mm) and 0.1 mm (95% CI, − 0.59 to 0.6 mm) smaller than OCT respectively. There was a satisfactory correlation (r = 0.63, p = < 0.0001) between QCA and OCT for MLD. However, the MLD by QCA was 0.49 mm (95% CI, − 1.57 to 0.59 mm) smaller than OCT, suggesting a poor agreement for MLD. Conclusions There is a good correlation and agreement between QCA and OCT for measurement of proximal and distal reference diameters. However, the MLD was underestimated by QCA.

Optical coherence tomography: not quite ready

Intravascular imaging has revolutionised the way coronary intervention has been viewed. Both intravascular ultrasound (IVUS) and, to a greater degree, optical coherence tomography (OCT), allow exquisite assessment of the luminal wall and structure to a near-histological tissue assessment level. OCT also allows detailed assessment of stent characteristics and, in particular, of adequacy of deployment and early identifi cation of procedural complications, such as edge dissections. Although this level of imaging provides invaluable information for the interventionalist, data are scarce for its use in clinical practice to improve outcomes. Previously, fi ndings from retrospective observational studies have shown benefi ts with use of OCT compared with angiography alone; however, OCT has not been robustly challenged in the setting of a randomised trial until now. Ziad Ali and colleagues are to be congratulated for the ILUMIEN III: OPTIMIZE PCI trial, published in The Lancet, which was a considered and well conducted prospective, multicentre, randomised, controlled trial. It aimed to show non-inferiority of OCT to IVUS in achievement of a minimal stent area (MSA) and superiority to angiography alone. The rationale for the choice of MSA as the primary endpoint was based on fi ndings from previous studies showing lower IVUSderived MSA as being associated with greater in-stent stenosis (late lumen loss) in drug-eluting and baremetal stents. The study achieved its prespecifi ed non-inferiority result with regards to MSA compared with IVUS (onesided 97·5% lower confi dence interval –0·70 mm2; p=0·001); however, it did not show superiority to angiography alone (p=0·42). Ali and colleagues also found that OCT guidance was associated with fewer untreated major dissections than with IVUS (19 [14%] of 140 vs 35 [26%] of 135; p=0·009) and fewer major stent malappositions (15 [11%] vs 28 [21%]; p=0·02). Although this fi nding certainly appears to be important, the clinical signifi cance of these imaging-detected complications remains to be further elucidated. Indeed, use of potential surrogate measures of clinical outcomes (the primary measure and focus of this study) should be viewed with caution. The notion of changing management by a strategy such as OCT because of its ability to detect suboptimal stent deployment is based on perceived issues or problems rather than real validated prospective clinical outcomes. This putative advantage has been speculated as a benefi t for years, yet has not translated into any meaningful clinical result yet. This issue is coupled with fundamental design comparator issues, which form the basis of the noninferiority design—ie, no accepted standard to size vessels with IVUS (luminal or media-to-media) or angiography (so-called eyeballing vs quantitative coronary angiography). The basis of sizing of a vessel with use of the proposed external elastic lamina-based OCT technique was achieved by operators in 85% of cases and used only in 75% of cases. Furthermore, operators using this technique had considerable expertise in intravascular imaging, meaning its broad applicability is unknown. Although OCT represents a visually powerful tool, which can provide insights during situations of uncertainty or complex percutaneous coronary intervention, its safety in routine clinical practice remains paramount. Largely, this safety was substantiated in this trial, although OCT was associated with increased procedural time and contrast use than with angiography. Although the numbers of adverse events are too small for analysis, procedural major adverse cardiac events were increased in the OCT group (four [3%] compared with one [1%] each in the IVUS and angiography-alone groups; p=0·37 for OCT vs angiography). Furthermore, at 30 days, only one (1%) stent thrombosis occurred, in the OCT group, showing Published Online October 30, 2016 http://dx.doi.org/10.1016/ S0140-6736(16)32062-1

The Presence of a CTO in a Non–Infarct-Related Artery During a STEMI Treated With Contemporary Primary PCI Is Associated With Increased Rates of Early and Late Cardiovascular Morbidity and Mortality: The CTO-TOTAL Substudy

In patients with a ST-segment elevation myocardial infarction (STEMI), the prevalence of chronic total occlusion (CTO) in a non–infarct-related artery (non-IRA) is 8% to 15% [(1)][1] with 2-fold greater morbidity and mortality than in those with single-vessel disease (SVD) [(2)][2]. The TOTAL (

In vivo morphologic comparison of saphenous vein grafts and native coronary arteries following non-ST elevation myocardial infarction

OBJECTIVE This study aimed to assess the pathophysiological differences between saphenous vein grafts (SVG) and native coronary arteries (NCA) following presentation with non-ST elevated myocardial infarction (NSTEMI). BACKGROUND There is accelerated pathogenesis of de novo coronary disease in harvested SVG following coronary artery bypass (CABG) surgery, which contributes to both early and late graft failure, and is also causal in adverse outcomes following vein graft PCI. However in vivo assessment, with OCT imaging, comparing the differences between vein grafts and NCAs has not previously been performed. METHODS We performed a retrospective, observational, analysis in patients who underwent PCI with adjunctive OCT imaging following presentation with NSTEMI, where the infarct-related artery (IRA) was either in an SVG or NCA. RESULTS A total of 1550 OCT segments was analysed from thirty patients with a mean age of 66.3 (±9.0) years were included. The mean graft age of 13.9 (±5.6) years in the SVG group. OCT imaging showed that the SVG group had evidence of increased lipid pool burden (lipid pool quadrants, 2.1 vs 2.7; p = 0.021), with a reduced fibro-atheroma cap-thickness in the SVG group (45.0 μm vs 38.5 μm; p = 0.05) and increased burden of calcification (calcified lesion length = 0.4 mm vs 1.8 mm; p = 0.007; calcified quadrants = 0.2 vs 0.9; p = 0.001; arc of superficial calcium deposits = 11.6° vs 50.9°; p = 0.007) when compared to NCA. CONCLUSION This OCT study has demonstrated that vein grafts have a uniquely atherogenic environment which leads to the development of calcified, lipogenic, thin-capped fibro-atheromas, which may be pivotal in the increased, acute and chronic graft failure rate, and may underpin the increased adverse outcomes following vein graft PCI.

Contemporary Management of ST-Elevation Myocardial Infarction

Recent advances have caused a major shift in the way ST-elevation myocardial infarctions are managed. This review explores the pharmacological and interventional techniques that have evidence for improving outcomes and the landmark trials that have sparked change. The new P2Y12 inhibitors, ticagrelor and prasugrel, have been shown to be superior to clopidogrel in STEMI patients undergoing primary percutaneous coronary intervention. Concurrently, many technical aspects of percutaneous coronary intervention have been further clarified by trial data, with bare-metal stents, routine thrombus aspiration and femoral access showing evidence of inferiority. Ongoing trials will provide more information on the role of non-culprit lesion PCI, bioresorbable vascular scaffolds, mechanical devices in persistent ischaemia and early automatic implantable cardioverter-defibrillators for inducible ventricular tachycardia.

Impact of Multivessel Coronary Artery Disease on Serum Biochemical Markers and Clinical Outcomes Following Acute Myocardial Infarction Treated with Percutaneous Coronary Intervention

no disease. Future studies will investigate the underlying mechanisms of cytokines in CAD. http://dx.doi.org/10.1016/j.hlc.2013.05.102