Background-Experimental studies suggest that low wall shear stress (WSS) promotes plaque development and high WSS is associated with plaque destabilization. We hypothesized that low-WSS segments in patients with coronary artery disease develop plaque progression and high-WSS segments develop necrotic core progression with fibrous tissue regression. Methods and Results-Twenty patients with coronary artery disease underwent baseline and 6-month radiofrequency intravascular ultrasound (virtual histology intravascular ultrasound) and computational fluid dynamics modeling for WSS calculation. For each virtual histology intravascular ultrasound segment (nϭ2249), changes in plaque area, virtual histology intravascular ultrasound-derived plaque composition, and remodeling were compared in low-, Key Words: atherosclerosis Ⅲ coronary artery disease Ⅲ hemodynamics Ⅲ intravascular ultrasonography, interventional Ⅲ wall shear stress A lthough cardiovascular risk factors lead to systemic inflammation, oxidative stress, and endothelial dysfunction, it is recognized that coronary atherosclerotic plaques are focally distributed with highly variable rates of progression. However, prediction of regional plaque progression in an individual coronary segment remains elusive. Editorial see p 763 Clinical Perspective on p 788Alterations in wall shear stress (WSS) have been implicated in the focal distribution and pathophysiology of coronary atherosclerosis. [1][2][3][4][5] Low WSS leads to a proatherogenic endothelial cell phenotype 1-3 and focal development of atherosclerosis and vascular remodeling in experimental models 6 -8 and pilot clinical studies. 9,10 Both low WSS and high WSS have been implicated in the production of matrix metalloproteinases and plasmin by endothelial cells that can destabilize plaque fibrous caps. [11][12][13] In addition, high WSS has been shown to induce apoptosis of smooth muscle cells, 14,15 which might enhance plaque vulnerability.To date, the role of both low WSS and high WSS in the development of plaque progression, change in plaque com- Received January 23, 2011; accepted May 9, 2011 Methods Study PopulationTwenty patients presenting to the cardiac catheterization laboratory at Emory University Hospital between December 2007 and January 2009 with an abnormal noninvasive stress test or stable anginal syndromes and found to have a nonobstructive lesion requiring invasive physiological evaluation were enrolled. Exclusion criteria included myocardial infarction, cardiogenic shock or hemodynamic instability, lesion requiring percutaneous or surgical revascularization, coronary artery bypass surgery, severe valvular heart disease, presence of visual coronary collaterals, inability to provide informed consent, serum creatinine Ͼ1.5 mg/dL, liver disease, or significant hematologic disease. All patients underwent baseline and 6-month follow-up radiofrequency backscatter IVUS (VH-IVUS) and baseline computational fluid dynamics (CFD) modeling for WSS calculation. All patients underwent lipid profile assessm...

Background-Intravascular ultrasound of drug-eluting stent (DES) thrombosis (ST) reveals a high incidence of incomplete stent apposition (ISA) and vessel remodeling. Autopsy specimens of DES ST show delayed healing and hypersensitivity reactions. The present study sought to correlate histopathology of thrombus aspirates with intravascular ultrasound findings in patients with very late DES ST. Methods and Results-The study population consisted of 54 patients (28 patients with very late DES ST and 26 controls).Of 28 patients with very late DES ST, 10 patients (1020Ϯ283 days after implantation) with 11 ST segments (5 sirolimus-eluting stents, 5 paclitaxel-eluting stents, 1 zotarolimus-eluting stent) underwent both thrombus aspiration and intravascular ultrasound investigation. ISA was present in 73% of cases with an ISA cross-sectional area of 6.2Ϯ2.4 mm 2 and evidence of vessel remodeling (index, 1.6Ϯ0.3). Histopathological analysis showed pieces of fresh thrombus with inflammatory cell infiltrates (DES, 263Ϯ149 white blood cells per high-power field) and eosinophils (DES, 20Ϯ24 eosinophils per high-power field; sirolimus-eluting stents, 34Ϯ28; paclitaxel-eluting stents, 6Ϯ6; P for sirolimus-eluting stents versus paclitaxel-eluting stentsϭ0.09). The mean number of eosinophils per high-power field was higher in specimens from very late DES ST (20Ϯ24) than in those from spontaneous acute myocardial infarction (7Ϯ10), early bare-metal stent ST (1Ϯ1), early DES ST (1Ϯ2), and late bare-metal stent ST (2Ϯ3; P from ANOVAϭ0.038). Eosinophil count correlated with ISA cross-sectional area, with an average increase of 5.4 eosinophils per high-power field per 1-mm 2 increase in ISA cross-sectional area. Conclusions-Very

Structured Abstract Background Multiple scoring systems have been devised to quantify angiographic coronary artery disease (CAD) burden, but it is unclear how these scores relate to each other and which scores are most accurate. The aim of this study was to compare coronary angiographic scoring systems 1) with each other and 2) with intravascular ultrasound (IVUS) derived plaque burden in a population undergoing angiographic evaluation for CAD. Methods Coronary angiographic data from 3600 patients was scored using 10 commonly used angiographic scoring systems and inter-score correlations were calculated. In a subset of 50 patients, plaque burden and plaque area in the left anterior descending coronary artery was quantified using IVUS and correlated with angiographic scores. Results All angiographic scores correlated with each other (range for Spearman coefficient (ρ): 0.79-0.98, p<0.0001); the two most widely used scores, Gensini and CASS-70, had a ρ = 0.90, p<0.0001. All scores correlated significantly with average plaque burden and plaque area by IVUS (range ρ: 0.56-0.78, p<0.0001 and 0.43-0.62, p<0.01, respectively). The CASS-50 score had the strongest correlation (ρ: 0.78 and 0.62, p<0.0001) and the Duke Jeopardy score the weakest correlation (ρ: 0.56 and 0.43, p<0.01) with plaque burden and area, respectively. Conclusions Angiographic scoring systems are strongly correlated with each other and with atherosclerotic plaque burden. Scoring systems therefore appear to be a valid estimate of CAD plaque burden.

This is a prepublication version of an article that has undergone peer review and been accepted for publication but is not the final version of record. This paper may be cited using the DOI and date of access. This paper may contain information that has errors in facts, figures, and statements, and will be corrected in the final published version. The journal is providing an early version of this article to expedite access to this information. The American Academy of Pediatrics, the editors, and authors are not responsible for inaccurate information and data described in this version.

Patients with myocardial bridges are often asymptomatic but this anomaly may be associated with exertional angina, acute coronary syndromes, cardiac arrhythmias, syncope or even sudden cardiac death. This review presents our understanding of the pathophysiology of myocardial bridging and describes prevailing diagnostic modalities and therapeutic options for this challenging clinical entity.

РезюмеОсобую группу ятрогений составляют осложнения, связанные с различными диагностическими манипуляциями -от физикального об-следования больного до ангиографических исследований, диагностической лапароскопии или торакоскопии. В статье приводятся данные о частоте и характере диагностических ятрогений в клинической практике. Диапазон диагностических ятрогений по своим проявлениям, тяжести и прогнозу достаточно широк -от раздражения кожи гелем при проведении УЗИ до диссекции коронарной артерии во время коро-нароангиографии. В статье представлены примеры ятрогений диагностических процедур, начиная с процесса клинического обследования (сбор жалоб и анамнеза, физикальное исследование), и заканчивая сложными инвазивными обследованиями. Подробно рассмотрены ятро-гении, возникающие при применении препаратов, содержащих контраст (в частности йодсодержащих препаратов), которые достаточно ши-роко используются в клинической практике (КТ с контрастированием, ангиографии и др.) с диагностической целью. В статье рассказывается о факторах риска, знание которых и осведомленность об их наличии у пациента обязательны перед введением препаратов, содержащих контраст. Проведен обзор осложнений, возникающих при эндоскопических исследованиях. Автор напоминает, что ятрогенные события при эндоскопических процедурах могут проявляться не только осложнениями со стороны исследуемого органа (пищевод, желудок, кишечник), но зависят также и от состояния больного, его подготовки к проведению процедуры, владения специалистом техникой эндоскопии. В за-ключение автор приводит клиническое наблюдение, в котором фактором риска ятрогенного события было наличие у больной аномалии протоковых систем печени и поджелудочной железы. Автор статьи призывает коллег более внимательно относиться к процессу принятия решения о проведении диагностического исследования, всегда оценивать соотношение польза/риск с точки зрения реальной пользы диа-гностического исследования для больного и риска развития осложнения. Ключевые слова: ятрогения, контраст-индуцированная нефропатия, коронароангиография, эндоскопия, эзофагогастродуоденоско-пия, колоноскопия AbstractA special group of iatrogenic complications are associated with various diagnostic manipulations -from a physical examination of the patient to angiographic studies, diagnostic laparoscopy or thoracoscopy. The article presents data on the frequency and nature of diagnostic iatrogenic in clinical practice. The range of diagnostic iatrogenesis in terms of its manifestations, severity and prognosis is wide enough -from skin irritation with gel during ultrasound to dissection of the coronary artery during coronary angiography. The article presents examples of iatrogenic diagnostic procedures, starting with the clinical examination process (collection of complaints and anamnesis, physical examination), and ending with complex invasive examinations. Yatrogenia, which occur with the use of preparations containing contrast (in particular iodine-containing drugs), which are widely used in clinical practice (CT with contras...

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