Intracoronary Ultrasound Imaging Research Articles

Intracoronary Ultrasound Imaging Combined with Traditional Chinese Medicine Nursing Applied in the Treatment of Coronary Heart Disease Patients with Phlegm and Blood Stasis Syndrome

This study was to explore the effect of traditional Chinese medicine (TCM) nursing intervention based on intracoronary ultrasound imaging on patients with coronary heart disease (CHD) and phlegm and blood stasis syndrome (PBSS). 100 hospitalized patients with CHD with Qi deficiency and blood stasis syndrome (QDBSS) were rolled into the experimental (Exp) group (routine nursing intervention) and control (Ctrl) group (TCM nursing intervention, syndrome differentiation nursing), with 50 patients in each group. They underwent the intracoronary ultrasound imaging scanning. The results showed that after intervention, the plaque load (45.08 ± 6.02%), plaque eccentricity index (0.47 ± 0.08%), vascular remodeling index (0.53 ± 0.11%), and vascular external elastic membrane area (8.67 ± 3.06 mm2) of the Exp group were notably inferior to those of the Ctrl group (60.22 ± 5.82%, 0.59 ± 0.08%, 0.71 ± 0.09%, and 10.56 ± 2.31 mm2). The total effective rate in the Exp group (88%) was greatly superior to that of the Ctrl group (68%). In terms of TCM symptom scores, the TCM symptom scores of chest pain, chest tightness, and shortness of breath in the Exp group after intervention (1.07 ± 0.21 points, 0.75 ± 0.27 points, and 0.58 ± 0.12 points) were notably inferior to those in the Ctrl group (1.62 ± 0.28 points, 1.03 ± 0.21 points, and 0.79 ± 0.14 points). In the Exp group, after intervention, the degree of physical activity limitation (67.05 ± 5.08 points), the stable state of angina pectoris (65.28 ± 3.76 points), the frequency of angina pectoris attack (85.92 ± 2.97 points), the degree of treatment satisfaction (75.39 ± 5.94 points), the cognition score of disease (63.56 ± 5.84 points), the levels of triglyceride (1.27 ± 0.41 mmol/L), and total cholesterol (2.24 ± 0.41 mmol/L) were remarkably inferior to the Ctrl group (52.97 ± 4.31 points, 50.77 ± 4.69 points, 71.36 ± 3.77 points, 64.08 ± 5.64 points, 51.77 ± 6.33 points, 2.09 ± 0.57 mmol/L, and 3.06 ± 0.84 mmol/L) (P < 0.05). It suggested that intracoronary ultrasound imaging can clearly display the coronary plaques of patients and accurately evaluate the clinical efficacy of patients with CHD. The TCM nursing program can greatly improve the angina symptoms and quality of life of patients with CHD and PBSS, reduce blood lipid levels, and effectively improve the clinical efficacy of patients.

Basic interpretation of intracoronary ultrasound and optical coherence tomography images: examples

Basic interpretation of intracoronary ultrasound and optical coherence tomography images: examples

Automated detection of cardiac phase from intracoronary ultrasound image sequences.

Intracoronary ultrasound (ICUS) is a widely used interventional imaging modality in clinical diagnosis and treatment of cardiac vessel diseases. Due to cyclic cardiac motion and pulsatile blood flow within the lumen, there exist changes of coronary arterial dimensions and relative motion between the imaging catheter and the lumen during continuous pullback of the catheter. The action subsequently causes cyclic changes to the image intensity of the acquired image sequence. Information on cardiac phases is implied in a non-gated ICUS image sequence. A 1-D phase signal reflecting cardiac cycles was extracted according to cyclical changes in local gray-levels in ICUS images. The local extrema of the signal were then detected to retrieve cardiac phases and to retrospectively gate the image sequence. Results of clinically acquired in vivo image data showed that the average inter-frame dissimilarity of lower than 0.1 was achievable with our technique. In terms of computational efficiency and complexity, the proposed method was shown to be competitive when compared with the current methods. The average frame processing time was lower than 30 ms. We effectively reduced the effect of image noises, useless textures, and non-vessel region on the phase signal detection by discarding signal components caused by non-cardiac factors.

Lone aspiration thrombectomy without stenting for a patient with ST-segment elevation myocardial infarction associated with coronary ectasia

A 57-year-old male with a previous history of inferior myocardial infarction suffered from chest pain and diagnosed as ST-segment elevation myocardial infarction (STEMI). Coronary angiography revealed a thrombus with delayed filling in the distal right coronary artery. After an aspiration thrombectomy, TIMI 3 flow was restored successfully. An intracoronary ultrasound imaging revealed coronary ectasia. Stenting and ballooning were deferred. A successful lone aspiration thrombectomy was performed for a patient with STEMI associated with coronary ectasia.

Compensation of in-plane rigid motion for in vivo intracoronary ultrasound image sequence

Intracoronary ultrasound (ICUS) is an interventional imaging modality that is used to acquire a series of tomographic images from the vascular lumen, for diagnosis and treatment of coronary artery diseases in clinical settings. Motion artifacts caused by cardiac dynamics and the pulsatile blood flow within the vascular lumen, during continuous pullback (non-gated) ICUS image acquisition, hinder visualization of longitudinal cuts, assessment of arterial morphology and hemodynamics, and three-dimensional (3-D) vessel reconstruction. The aim of this study is to develop a method to compensate for in-plane rigid motion in non-gated in vivo ICUS sequences. The signals associated with cardiac motion are first detected from the gray-scale image sequence. They are represented with rigid motion parameters between luminal contours extracted from successive slices. Subsequently, the signals were filtered to separate the dynamic components caused by cardiac motion from those caused by the irregular morphology of the vascular lumen. Dynamic components were then compensated by performing a back transformation of related pixels within the vessel region in each frame. The method is validated by computer-simulation and using real ICUS image data. Possible sources of error are discussed based on the experimental results.

An off-line gating method for suppressing motion artifacts in ICUSsequence

Intracoronary ultrasound (ICUS) imaging, an invasive catheter-based imaging modality, has been widely used in clinical diagnosis of coronary artery diseases. Motion artifacts due to cyclic cardiac motion and pulsatile blood are the main factors that hinder the visualization of ICUS longitudinal cut and 3D vessel reconstruction from ICUS image sequence. The aim of this work is to propose an off-line gating method based on ICUS image properties to suppress motion artifacts for continuous pullback ICUS image sequences acquired in vivo covering several cardiac cycles without the help of ECG signals. Based on analysis of intensity features of each ICUS frame, a difference matrix is firstly constructed. Then, potential information about cardiac cycle is extracted from the matrix and the correspondence of each ICUS frame in successive cardiac cycles is obtained through finding a globally optimal path with the lowest cumulative difference value in the matrix. Finally, a subsequence of frames each acquired at the end-diastole of each cardiac cycle is selected to obtain the gated sequence. The main advantage of this method is that it is applicable to those ICUS sequences where the subject’s heart rate may be irregular during image acquisition. Also, any high-level image analysis performed to ICUS images is not needed. Results are given for clinical image data of patients in order to validate the proposed method.

Advances in Intravascular Imaging

Received March 25, 2009; accepted August 4, 2009. This review updates the role of various intravascular imaging techniques (1) in the detection of vulnerable plaque and (2) during percutaneous coronary intervention (PCI), especially drug-eluting stent (DES) implantation and follow-up—including intravascular ultrasound (IVUS), virtual histology (VH-IVUS) and integrated backscatter (IB-IVUS), optical coherent tomography (OCT), near-infrared (NIR) spectroscopy, angioscopy, and MRI. ### IVUS, IB-IVUS, and VH-IVUS The current intracoronary ultrasound imaging frequency range of 20 to 45 MHz provides 70 to 200 μm axial resolution with >5 mm penetration.1,2 Grayscale IVUS allows robust quantitative measurements including lumen, vessel, and plaque area; qualitative assessment of lesions preintervention; and quantitative assessment and complications of lesions postintervention; however, it has poor sensitivity for detecting lipid-rich plaque (67%).3 High-frequency IVUS transducers can produce better resolution that should also improve plaque characterization but at the trade off of greater ultrasound reflection from blood. Blood speckle with >40 MHz ultrasound can cause confusion when identifying the lumen-tissue border, detecting in-stent neointimal tissue, etc; but it is easily solved by saline (negative contrast) injection through the guiding catheter.4 Standard grayscale IVUS is limited, in part, because it uses only reflected ultrasound amplitude to formulate the image and requires significant postprocessing. In an effort to improve on the qualitative assessment of the reflected ultrasound signal, Kawasaki et al developed a plaque characterization algorithm called IB-IVUS using time domain information directly from the radiofrequency signal. This process has resulted in improved plaque characterization with a reported in vitro sensitivity of 90% and specificity or 92% for lipid-rich plaque.5,6 In a similar effort to improve plaque characterization, spectral analysis (VH-IVUS) combined frequency and amplitude analysis and used an algorithm developed from known tissue types to detect fibrous plaque, fibrofatty plaque, necrotic core (NC), and dense calcium (Figure 1A′, 1B′). Reported sensitivity and …

Late Stent Thrombosis After Drug-Eluting Stent

Following the inspiration of Dr S. Windecker, the team from Bern, Switzerland, has contributed >30 studies on drug-eluting stent efficacy and safety, several of which represent essential pieces in the puzzle. The article in this issue of Circulation by Cook et al1 belongs to that select group of key references. The series of robust and detailed reports on the Bern-Rotterdam cohort studies have coined the 0.6% yearly linear rate of definite late stent thrombosis associated with the permanent coronary implantation of first-generation drug-eluting stents.2 Intravascular ultrasound imaging of the thrombosed stents has revealed the strong association of incomplete strut apposition with the event.3 At the same time, collective analysis of all the available evidence4 demonstrated that a reduction in restenosis with drug-eluting stents prevented adverse events caused by the treatment of the more frequent recurrences with bare metal stents. With the former compensating for the latter, the net result of this balancing act between safety and efficacy resulted in no difference in death and myocardial infarction rates up to 4 years after the initial procedure. Article see p 391 In the present study, late hypersensitivity reaction was identified as a cause for late stent thrombosis, in association with stent malapposition caused by necrotizing vasculitis around the stent struts. Histopathological analysis of aspirated thrombus showed eosinophilic infiltration typical for type IVb hypersensitivity reaction following implantation of sirolimus-eluting stents. Macrophage infiltration typical for type IVc hypersensitivity was seen with paclitaxel-eluting stents. The biomarker gradient between coronary and peripheral blood was significant for high-sensitivity C-reactive protein and myeloid-related protein 8/14, both markers of local inflammatory reaction. These patterns were not observed with early drug-eluting stent thrombosis, early …

Myocardial Bridging

According to postmortem studies, coronary atherosclerosis can be substantial and reach a high prevalence of advanced lesions, including atheroma and fibroatheroma in young adults.1,2 Risk factors associated with coronary atherosclerosis such as dyslipidemia, smoking, diabetes mellitus, and hypertension have been identified. The development of atherosclerosis seems to be related to the magnitude and duration of exposure.3 Although research concentrates on identifying genetic markers in genome-wide association studies, there is still a lack of knowledge about the individual risk of developing coronary atherosclerosis.4 When atherosclerosis presents as acute coronary syndromes, mortality may be high.5 Plaque rupture and erosion have been identified as major underlying pathological-anatomic characteristics,6 but some suspect other mechanisms.7 In this issue of Circulation , Ishikawa et al8 present evidence that myocardial bridging may play a role as a congenital anatomic risk factor for coronary atherosclerosis and myocardial infarction. Article see p 376 Myocardial bridging results when myocardial tissue covers part of the left anterior descending coronary artery, resulting in a tunneled arterial segment, which can be regarded as a congenital variant.9–11 The prevalence is reported to be >50% at autopsy.12 Clinically, the diagnosis of myocardial bridging is established by coronary angiography demonstrating a systolic compression, described as a “milking effect,”13 but it was present in only <5% of cases recently in a large number of Chinese patients.14 When nitroglycerin was used as …

Instent neointimal hyperplasia after percutaneous intervention for ST-elevation myocardial infarction and treatment with granulocyte-colony stimulating factor. Results from the stem cells in myocardial infarction (STEMMI) trial

BackgroundRecombinant granulocyte-colony stimulating factor (G-CSF) mobilized pluripotent cells from the bone marrow are proposed to have a regenerative potential. Though, a report of excessive instent restenosis, in patients treated with G-CSF before percutaneous coronary intervention (PCI) warrants caution. MethodsPatients (n=59) enrolled in the STEMMI trial, a randomized and double blind study, comparing G-CSF and placebo after large ST-elevation myocardial infarctions, had an intracoronary ultrasound imaging at 6 months follow-up with a quantitative analysis of instent neointimal hyperplasia. ResultsDuring G-CSF treatment leukocyte counts, and CD34+ and CD45−/CD34− cell fractions in peripheral blood increased markedly (p<0.0001 vs. placebo). At follow-up, there were no differences in intracoronary late lumen loss, expressed as neointima volume per mm of stent (1.6 mm3±1.2 [G-CSF group] vs. 1.9 mm3±1.3 [placebo group]; p=0.38), and in minimal instent lumen area (5.4 mm2±2.4 vs. 5.3 mm2±2.6, p=0.90). In the placebo group, plasma concentration of stromal cell-derived factor-1 (SDF-1) increased significantly after STEMI. This SDF-1 response was completely suppressed during G-CSF treatment. A rebound increase of SDF-1 was observed after withdrawal of G-CSF (p=0.001). Plasma concentration of SDF-1 at the time of stent implantation correlated positively to neointimal hyperplasia (p=0.025). ConclusionsG-CSF treatment, initiated after PCI, does not lead to excessive instent neointimal hyperplasia or restenosis in patients with STEMI. The timing of G-CSF, in relation to the PCI, might be important, as G-CSF influences SDF-1.

Three‐dimensional and quantitative analysis of atherosclerotic plaque composition by automated differential echogenicity

To validate automated and quantitative three-dimensional analysis of coronary plaque composition using intracoronary ultrasound (ICUS). ICUS displays different tissue components based on their acoustic properties in 256 grey-levels. We hypothesised that computer-assisted image analysis (differential echogenicity) would permit automated quantification of several tissue components in atherosclerotic plaques. Ten 40-mm-long left anterior descending specimens were excised during autopsy of which eight could be successfully imaged by ICUS. Histological sections were taken at 5 mm intervals and analyzed. Since most of the plaques were calcified and having a homogeneous appearance, one specimen with a more heterogeneous composition was further examined: at each interval of 5 mm, 15 additional sections (every 100 microm) were evaluated. Plaques were scored for echogenicity against the adventitia: brighter (hyperechogenic) or less bright (hypoechogenic). Areas of hypoechogenicity correlated with the presence of smooth muscle cells. Areas of hyperechogenicity correlated with presence of collagen, and areas of hyperechogenicity with acoustic shadowing correlated with calcium. None of these comparisons showed statistical significant differences. This ex vivo feasibility study shows that automated three-dimensional differential echogenicity analysis of ICUS images allows identification of different tissue types within atherosclerotic plaques. This technology may play a role as an additional tool in longitudinal studies to trace possible changes in plaque composition.

Online PC-based integration of digital intracoronary ultrasound images into angiographic images during cardiac catheterization

In recent years, intravascular ultrasound (IVUS) has evolved as an important adjunct to angiography, providing insights that are significantly altering conventional paradigms in diagnosis and therapy. However, major drawbacks in the use of IVUS relied on the fact that a heavy console had to be moved from lab to lab, and extensive time for set up and image analysis. This additional time and the decrease in patients’ through-put has not been applicable in clinical practice for many labs. Our manuscript concerns a novel PC-based platform for IVUS that enables the online intergration of digital intracoronary ultrasound images into angiographic images. This new technique offers remote operation, multiple control devices and custom viewing options. The PC-based platform enables IVUS images to be viewed simultaneously from multiple vantage points in the lab, and allows for multiple user interfaces.

Regions of low endothelial shear stress are the sites where coronary plaque progresses and vascular remodelling occurs in humans: an in vivo serial study

We performed serial intracoronary studies of patients with stable coronary artery disease (CAD) to investigate the relationships among baseline endothelial shear stress (ESS), CAD progression, and vascular remodelling. Local haemodynamic factors are critical determinants of plaque progression, vascular remodelling, and clinical CAD manifestations. The 3-D anatomy of coronary arteries with lumen obstruction <50% was determined by fusing intracoronary ultrasound and angiographic images in 13 patients at baseline and 8 +/- 2 months later. Cross-sectional area of plaque, lumen, and external elastic membrane (EEM), and coronary flow were measured. Local ESS was calculated. Subsegments with similar ESS were categorized based on low (<12 dynes/cm(2)) and moderate/higher ESS (> or =12 dynes/cm(2)). There were 47 subsegments of similar baseline ESS: nine with low ESS and 38 with moderate/higher ESS. Median subsegment length was 6.9 mm (25th-75th percentiles = 4.2-12.0), and median area of similar ESS of 52.6 mm(2) (25th-75th percentiles = 26.9-88.0). Subsegments with low ESS exhibited plaque progression when compared with subsegments with moderate/higher ESS (33.3% vs. 7.9%, respectively, P = 0.009 adjusted for clustering of lesions within patients) and constrictive remodelling (44.0% vs. 5.3%, respectively, P = 0.16 adjusted for clustering of lesions within patients). Expansive remodelling occurred with similar frequency in subsegments with low vs. moderate/higher baseline ESS. Plaque progresses in subsegments with low ESS, associated with either constrictive or expansive remodelling. Different mechanisms are likely responsible for expansive remodelling in different local vascular environments. Early in vivo identification of arterial subsegments likely to develop high-risk plaque characteristics may allow for selective interventions to avoid adverse cardiac outcomes.

Issue Highlights

HomeCirculationVol. 113, No. 13Issue Highlights Free AccessIn BriefPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessIn BriefPDF/EPUBIssue Highlights Originally published4 Apr 2006https://doi.org/10.1161/circ.113.13.1633Circulation. 2006;113:1633CLINICAL FEATURES OF ARRHYTHMOGENIC RIGHT VENTRICULAR DYSPLASIA/CARDIOMYOPATHY ASSOCIATED WITH MUTATIONS IN PLAKOPHILIN-2, by Dalal et al.andPLAKOPHILIN-2 MUTATIONS ARE THE MAJOR DETERMINANT OF FAMILIAL ARRHYTHMOGENIC RIGHT VENTRICULAR DYSPLASIA/CARDIOMYOPATHY, by van Tintelen et al.Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) may be challenging to diagnose because of variable expressivity and penetrance. There are multiple gene mutations responsible for the disease, with overlapping clinical phenotypes, analogous to other inherited cardiac diseases with arrhythmia vulnerability. Most of the genes associated with ARVD/C encode for desmosomal proteins involved in cell-to-cell adhesion. In this issue of Circulation, 2 reports by Dalal et al and van Tintelen et al sought to determine the prevalence and clinical expression of mutations in the plakophilin-2 gene (PKP2) in ARVD/C patients. Both groups found a high frequency of PKP2 mutations in patients with familial ARVD/C. Dalal and colleagues found that patients with PKP2 mutations presented earlier in life. However, neither study could identify distinguishing clinical features associated with PKP2 mutations compared with other (non-PKP2) patients with ARVD/C. They conclude that molecular genetic testing for PKP2 mutations may allow presymptomatic identification of ARVD/C and may refine treatment strategies. See pp 1641 and 1650 (and editorial on p 1634).EFFECT OF CLOPIDOGREL PREMEDICATION IN OFF-PUMP CARDIAC SURGERY: ARE WE FORFEITING THE BENEFITS OF REDUCED HEMORRHAGIC SEQUELAE? by Kapetanakis et al.Dual antiplatelet therapy with aspirin and clopidogrel reduces major adverse cardiovascular events after unstable angina, enhances infarct-related artery patency after thrombolytic therapy in ST-elevation myocardial infarction, and decreases post--percutaneous coronary intervention thrombotic complications after both elective and urgent stenting procedures. However, the enhanced efficacy of dual antiplatelet therapy is associated with an increased risk of bleeding that is particularly troublesome for patients requiring surgical revascularization because of the irreversible nature of clopidogrel action. In this issue of Circulation, Kapetanakis and colleagues report on their retrospective study of 1572 patients undergoing isolated off-pump coronary artery bypass surgery (OPCAB) to evaluate the effect of preoperative clopidogrel administration on bleeding. Risk-adjusted logistic regression and matched pair propensity score analyses demonstrated that clopidogrel preadministration increased the risk for hemostatic reoperation and blood transfusion requirements during and after OPCAB surgery. The findings of this nonrandomized, nonblinded retrospective analysis add to the controversy surrounding the optimal timing of clopidogrel administration given the nonsignificant trends for only modest increases in bleeding observed in patients who continued clopidogrel within 5 days before surgery in prospective, double-blind, randomized trials (Clopidogrel in Unstable Angina to Prevent Recurrent Events [CURE] and Clopidogrel as Adjunctive Reperfusion Therapy [CLARITY]-Thrombolysis in Myocardial Infarction [TIMI] 28). See p 1667.MAGNESIUM INTAKE AND INCIDENCE OF METABOLIC SYNDROME AMONG YOUNG ADULTS, by He et al.The metabolic syndrome is defined as a constellation of risk factors that appear to directly promote the development of atherosclerotic cardiovascular disease. Owing to its potential to adversely affect cardiovascular health, much attention is now focused on strategies that may prevent and treat this condition. Prior studies suggest that increased magnesium intake is associated with a more favorable lipid profile and a lower risk of hypertension and diabetes. Accordingly, these data prompt the question of whether there is a relationship between dietary magnesium and the development of metabolic syndrome. In this issue, He and colleagues report the results of their carefully conducted observational study to assess the association of dietary magnesium and the incidence of metabolic syndrome among 4637 young adults, who were followed up for 15 years. Their provocative results suggest a promising role for dietary magnesium intake that can only be verified by the future performance of randomized controlled trials. Whether taking magnesium supplements can provide similar benefits requires further study as well. See p 1675.Visit http://circ.ahajournals.org:Cardiology Patient PageCatheter Ablation of Atrial Fibrillation. See p e666.Images in Cardiovascular MedicineAcute Myocardial Infarction Caused by Extension of a Proximal Aortic Dissection Flap Into the Right Coronary Artery: An Intracoronary Ultrasound Image. See p e669. Download figureDownload PowerPoint“Shock Advised”: Inappropriate Public Access Defibrillation. See p e672.Magnetic Resonance Imaging and Computed Tomography Findings in Arrhythmogenic Right Ventricular Cardiomyopathy. See p e673.CorrespondenceSee p e676. Previous Back to top Next FiguresReferencesRelatedDetailsCited By Joondeph B Federalism, the Rehnquist Court, and the Modern Republican Party, SSRN Electronic Journal, 10.2139/ssrn.1019648 April 4, 2006Vol 113, Issue 13 Advertisement Article InformationMetrics https://doi.org/10.1161/circ.113.13.1633 Originally publishedApril 4, 2006 PDF download Advertisement

Acute Myocardial Infarction Caused by Extension of a Proximal Aortic Dissection Flap Into the Right Coronary Artery

A 69-year-old man with a history of hypertension was referred to our institution for management of acute myocardial infarction (AMI) and cardiogenic shock. The ECG showed a marked ST-segment elevation in leads II, III, and aVF and a reciprocal ST-segment depression in leads V2 through V6, suggesting an inferior wall AMI (Figure 1). Immediately after admission, the patient went into sudden cardiac and respiratory arrest and received cardiopulmonary resuscitation (CPR). A temporary pacemaker and an intra-aortic balloon pump were inserted during the CPR procedure, and emergent coronary angiography was performed. The right coronary angiogram showed no …

In-stent neo-intimal hyperplasia after stem cell mobilization by granulocyte-colony stimulating factor: Preliminary intracoronary ultrasound results from a double-blind randomized placebo-controlled study of patients treated with percutaneous coronary intervention for ST-elevation myocardial infarction (STEMMI Trial)

Objective The influence of treatment with granulocyte-colony stimulating factor (G-CSF) on the development of in-stent intimal hyperplasia is not known. We aimed to study this phenomenon in patients who had stents implanted in the course of an acute ST-elevation infarction and successively were treated with G-CSF. Method We performed angiography and intracoronary ultrasound follow-up after 5 months in 41 consecutive patients in the STEMMI trial, which is a randomized double-blind placebo-controlled study on the effect of G-CSF injections on the myocardial function following acute myocardial infarction in patients treated with primary percutaneous coronary stent implantation. The intracoronary ultrasound images were analyzed by a blinded and independent core laboratory. Results There were no differences in in-stent neo-intimal hyperplasia determined by intracoronary ultrasound between patients treated with G-CSF compared to patients treated with placebo. Neo-intimal hyperplasia per mm of stent was 1.87 (± 1.41) and 1.89 (± 1.39), respectively ( p = 0.97). Angiographic in-segment restenosis (> 50% diameter stenosis) was found in 28% of patients (24% in the G-CSF group and 33% in the placebo group; p = 0.55). Conclusion G-CSF treatment following coronary stent implantation in primary PCI treated AMI patients does not increase in-stent restenosis excessively and it does not seem warranted to limit further study of effects of G-CSF for that reason.

Coronary resistance system in evaluation of microvascular dysfunction after intracoronary microembolization: an experimental study

To assess the microvascular function of coronary artery after intracoronary microembolization using coronary resistance system. The left anterior descending coronary artery (LAD) of 10 pigs weighing 21 kg-25 kg were embolized by repetitive injection of microspheres 45 micro m in diameter through a 2.8F Tracker catheter. Intra-vascular ultrasound (IVUS) images, intracoronary Doppler and pressure signals in the middle segment of LAD were acquired by use of intracoronary ultrasound imaging catheter, Doppler flow wire and pressure wire separately. Intracoronary bolus injection of 18 micro g adenosine was administered to maximally vasodilate the coronary arterial bed through the 2.8F Tracker catheter. The resting and hyperemic signals were acquired respectively before microembolization and in different levels of microembolization. Coronary resistance system reflecting the resistance to pulsatile coronary flow was established by a self-made software of PC system. The resting and hyperemic CR parameters included average resting coronary resistance (rCR) and average minimal coronary resistance (min-CR), the first-harmonic rCR and min-CR, the first-harmonic rCR orientation and min-CR orientation, and so on. Factor analysis was performed to extract the best coronary parameter from the coronary resistance parameters. Factor analysis showed that the first-harmonic rCR and first-harmonic min-CR were correlated better with the first component extracted from the resting and hyperemic CR parameters than rCR and min-CR, with the correlation coefficient being 0.913 and 0.950 in the first-harmonic CR and first-harmonic min-CR respectively. No significant difference in min-CR was found between the value at the dosage of 5 x 10(4) microspheres and that before microembolization. The min-CR value increased markedly from 271 mm Hg.ml(-1).s(-1) +/- 99 mm Hg.ml(-1).s(-1) at the dosage of injecting 5 x 10(4) microspheres to 361 mm Hg.ml(-1).s(-1) +/- 158 mm Hg.ml(-1).s(-1) at the dosage of injecting 10 x 10(4) microspheres (P < 0.05). The min-CR value remained almost unchanged from the dosage of 10 x 10(4) to 15 x 10(4) microspheres. There was no significant difference concerning the first-harmonic min-CR between the value at the dosage of 5 x 10(4) microspheres and that before microembolization. Along with the increase of number of microspheres injected the min-CR value increased gradually. The min-CR value was increased significantly than that before microembolization since the number of microspheres injected surpassed 14 x 10(4). The first-harmonic min-CR reflected the coronary microvascular dysfunction in different extents of microembolization better than min-CR. The extent of coronary microvascular dysfunction wasn't linearly related to the extent of microembolization.

P3226 Retrospective image-based gating of intracoronary ultrasound images for improved quantitative analysis: the intelligate method

P3226 Retrospective image-based gating of intracoronary ultrasound images for improved quantitative analysis: the intelligate method

Serial intracoronary ultrasound in children: Feasibility, reproducibility, limitations, and safety

Pediatric patients with heart transplants and Kawasaki disease are at risk to develop coronary artery disease. Selective coronary angiography underestimates vasculopathy in transplant patients and intimal changes in Kawasaki disease. Routine intracoronary ultrasound imaging in adults accurately identifies histopathologic features not visualized by angiography. Little data are available regarding safety and efficacy in children. This study provides sequential data and experience in children between the ages of 2½ and 22 years. Thirty-two patients underwent 62 intracoronary ultrasound examinations at the time of coronary angiography. Careful correlation of the ultrasound crystal locations with the angiographic images of the vessels was made. Images were analyzed for intimal hyperplasia and luminal diameters. Intracoronary ultrasound was more sensitive than angiography in detecting vessel wall disease. Coronary vasospasm occurred in 11 of 62 studies after the intracoronary ultrasound study. All but 1 episode were asymptomatic and resolved after intracoronary nitroglycerine. When a standard protocol is followed and current technology is used, intracoronary ultrasound is feasible, reproducible, efficacious, and safe in the young patient. It allows earlier detection of vasculopathy and intimal disease at angiographically normal sites. As technology improves and greater experience is gained, the long-term safety and prognostic value of these studies in children should be forthcoming. (J Am Soc Echocardiogr 2002;15:782-90.)

Bayesian contour detection in a time series of ultrasound images through dynamic deformable template models.

Deformable template models and Markov chain Monte Carlo methods are used for analysing a space-time process of intracoronary ultrasound images in order to detect the artery contour and various other characteristics as a function of time.