Coronary Lumen Research Articles

Virtual intravascular endoscopy visualization of calcified coronary plaques: a novel approach of identifying plaque features for more accurate assessment of coronary lumen stenosis.

This study was conducted to investigate the feasibility of using 3D virtual intravascular endoscopy (VIE) as a novel approach for characterization of calcified coronary plaques with the aim of differentiating superficial from deep calcified plaques, thus improving assessment of coronary stenosis.A total of 61 patients with suspected coronary artery disease were included in the study. Minimal lumen diameter (MLD) was measured and compared between coronary CT angiography (CCTA) (≥64-slice) and invasive coronary angiography (ICA) with regard to the measurement bias, whereas VIE findings were correlated with CCTA with respect to the diagnostic performance of coronary stenosis and the area under the curve (AUC) by receiver-operating characteristic curve analysis (ROC).In all 3 coronary arteries, the CCTA consistently underestimated the MLD relative to the ICA (P < 0.001). On a per-vessel assessment, the sensitivity, specificity, positive predictive value, and negative predictive value and 95% confidence interval (CI) were 94% (95% CI: 61%, 100%), 27% (95% CI: 18%, 38%), 33% (95% CI: 23%, 43%), and 92% (95% CI: 74%, 99%) for CCTA, and 100% (95% CI: 89%, 100%), 85% (95% CI: 75%, 92%), 71% (95% CI: 56%, 84%), and 100% (95% CI: 95%, 100%) for VIE, respectively. The AUC by ROC analysis for VIE demonstrated significant improvement in analysis of left anterior descending calcified plaques compared with CCTA (0.99 vs 0.60, P < 0.001), with better performance in the left circumflex and right coronary arteries (0.98 vs 0.84 and 0.77 vs 0.77, respectively; P = 0.07 and P = 0.96, respectively). There are no significant differences between 64-, 128-, and 640-slice CCTA and VIE in terms of sensitivity, specificity, positive and negative predictive value in the diagnosis of coronary stenosis.This study shows the feasibility of using VIE for characterizing morphological features of calcified plaques, therefore, significantly improving assessment of coronary stenosis.

Abstract 149: Relationship between Epicardial Fat Thickness and Underlying Coronary Atherosclerotic Plaque Size and Burden

A paracrine effect of epicardial fat in underlying coronary atherosclerosis has been proposed, due to the inflammatory role of adipose tissue. Most studies evaluate globally fat (by magnetic resonance) and atherosclerosis (by computerized tomography). We analyzed microscopically, segment by segment, the potential local influence of fat in atherosclerotic plaque size and burden. Thickness of epicardial fat, coronary lumen area, and area delimited by the internal elastic lamina were measured with an image analysis system coupled to a light microscope, and plaque size (area delimited by the internal elastic lamina less lumen area) and burden (plaque area/ area delimited by the internal elastic lamina) were calculated in 192 coronary artery segments from 9 hearts from necropsies of patients that died with coronary atherosclerosis. To compare epicardial and myocardial faces of the arteries, the measures were made in each half; total amounts were also calculated. The relationships between epicardial fat and underlying atherosclerosis, both considering epicardial half and the whole segment, and between total fat and the total arterial segment, were tested by Pearson’s test. Plaque size and burden in each half were compared by paired Wilcoxon signed rank test. We considered correlation strength as r =0.10 to 0.29- weak, r = 0.30 to 0.49- medium, and r = 0.50 to 1.0- strong correlation, and results significant if P &lt; or = 0.05. Results: Correlation coefficients: epicardial face fat thickness - 1) with plaque area at epicardial half - r = 0.22, P &lt;0.01; 2) with plaque burden at epicardial half- r = 0.18, P =0.02; 3) with total plaque area- r = 0.19, P &lt;0.01; 4) with total plaque burden- r = 0.10, P =0.18; total epicardial fat thickness - 1) with total plaque area - r = 0.22, p&lt;0.01; 2) with total plaque burden- r = 0.06, P =0.39. Comparison between halves: area size - mean 1.20 mm at epicardial face and 1.5 mm at myocardial face, P =0.96; plaque burden - mean 33.7% at epicardial face and 45.7% at myocardial face, P =0.98. Conclusion: the correlations were weak and/or non-significant, and the atherosclerotic process involves equally both halves of the coronary arteries; thus our data indicate that there is no significant effect of fat tissue in underlying coronary atherosclerosis.

Abstract 367: Measurement of Lumen Dimensions in Non-stented and Stented Coronary Arteries: A Meta-analysis of Frequency Domain Optical Coherence Tomography versus Intravascular Ultrasound

Background: Intraluminal coronary morphology is traditionally evaluated by Intravascular Ultrasound (IVUS). Frequency Domain Optical Coherence Tomography (FD-OCT) is a novel method for evaluation of coronary lumen dimensions. Current literature has paucity of data with limited sample size comparing FD-OCT to IVUS. The objective of this meta-analysis is to compare the FD-OCT versus IVUS in assessment of lumen dimensions in non-stented and stented coronary arteries. Methods: PubMed and the Cochrane Center Register of Controlled Trials were searched through January 2015. Seven studies (n=169 vessels) comparing FD-OCT versus IVUS procedures in assessing lumen dimensions in non-stented and stented coronary arteries were included. Outcomes were minimum lumen area, minimum lumen diameter and maximum lumen diameter. The mean difference (MD) with 95% confidence interval (CI) was computed and p&lt;0.05 was considered as a level of significance. Results: FD-OCT measured significantly smaller minimum lumen area and maximum lumen diameter compared to IVUS in non-stented vessels (MD: -0.86 mm 2 , CI: -1.18 to -0.55, p&lt;0.00001 and MD: -0.21 mm, CI: -0.35 to -0.06, p=0.006, respectively). Minimum lumen diameter was not significantly different between two groups in non-stented coronary arteries (p=0.21). In stented vessels, no significant difference was found in measurement of minimum lumen area (p=0.34) and minimum lumen diameter (p=0.41) between FD-OCT and IVUS. Conclusion: The results of this study suggest that FD-OCT maybe a better modality to evaluate the severity of stenosis in non-stented coronary arteries. FD-OCT is comparable to IVUS in measuring lumen dimensions in stented vessels.

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

ObjectivesThere 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. MethodsPatients 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. ResultsOCT 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 0.09mm (95% CI, −0.52 to 0.53mm) and 0.1mm (95% CI, −0.59 to 0.6mm) 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 0.49mm (95% CI, −1.57 to 0.59mm) smaller than OCT, suggesting a poor agreement for MLD. ConclusionsThere 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.

Computer Vision Techniques for Transcatheter Intervention

Minimally invasive transcatheter technologies have demonstrated substantial promise for the diagnosis and the treatment of cardiovascular diseases. For example, transcatheter aortic valve implantation is an alternative to aortic valve replacement for the treatment of severe aortic stenosis, and transcatheter atrial fibrillation ablation is widely used for the treatment and the cure of atrial fibrillation. In addition, catheter-based intravascular ultrasound and optical coherence tomography imaging of coronary arteries provides important information about the coronary lumen, wall, and plaque characteristics. Qualitative and quantitative analysis of these cross-sectional image data will be beneficial to the evaluation and the treatment of coronary artery diseases such as atherosclerosis. In all the phases (preoperative, intraoperative, and postoperative) during the transcatheter intervention procedure, computer vision techniques (e.g., image segmentation and motion tracking) have been largely applied in the field to accomplish tasks like annulus measurement, valve selection, catheter placement control, and vessel centerline extraction. This provides beneficial guidance for the clinicians in surgical planning, disease diagnosis, and treatment assessment. In this paper, we present a systematical review on these state-of-the-art methods. We aim to give a comprehensive overview for researchers in the area of computer vision on the subject of transcatheter intervention. Research in medical computing is multi-disciplinary due to its nature, and hence, it is important to understand the application domain, clinical background, and imaging modality, so that methods and quantitative measurements derived from analyzing the imaging data are appropriate and meaningful. We thus provide an overview on the background information of the transcatheter intervention procedures, as well as a review of the computer vision techniques and methodologies applied in this area.

基于光线投射法的冠脉血管腔壁分割算法

基于光线投射法的冠脉血管腔壁分割算法

Coronary CT Angiography in Coronary Artery Disease: from Diagnosis to Prevention

Coronary CT angiography has emerged as reliable imaging tool for the diagnosis of coronary artery disease. Coronary CT angiography has the ability to demonstrate excellent visualization of anatomical changes in coronary artery with high diagnostic value in the detection of lumen stenosis or occlusion, and characterization of coronary plaque composition. Furthermore, coronary CT angiography offers prognostic value in the prediction of adverse cardiac events. Although coronary CT angiography is limited to the assessment of coronary anatomy and lumen changes, coronary CT angiography-derived computer modeling and hemodynamic analysis has the potential to evaluate functional significance of coronary artery disease. This review article aims to provide an overview of both diagnostic and prognostic value of coronary CT angiography in coronary artery disease. Limitations of coronary CT angiography are briefly discussed, while functional assessment of coronary artery disease with use of coronary CT angiography-generated coronary artery models is highlighted.

Hand2 Is an Essential Regulator for Two Notch-Dependent Functions within the Embryonic Endocardium

The basic-helix-loop-helix (bHLH) transcription factor Hand2 plays critical roles during cardiac morphogenesis via expression and function within myocardial, neural crest, and epicardial cell populations. Here, we show that Hand2 plays two essential Notch-dependent roles within the endocardium. Endocardial ablation of Hand2 results in failure to develop a patent tricuspid valve, intraventricular septum defects, and hypotrabeculated ventricles, which collectively resemble the human congenital defect tricuspid atresia. We show endocardial Hand2 to be an integral downstream component of a Notch endocardium-to-myocardium signaling pathway and a direct transcriptional regulator of Neuregulin1. Additionally, Hand2 participates in endocardium-to-endocardium-based cell signaling, with Hand2 mutant hearts displaying an increased density of coronary lumens. Molecular analyses further reveal dysregulation of several crucial components of Vegf signaling, including VegfA, VegfR2, Nrp1, and VegfR3. Thus, Hand2 functions as a crucial downstream transcriptional effector of endocardial Notch signaling during both cardiogenesis and coronary vasculogenesis.

Mechanisms of balloon angioplasty and repeat stenting in patients with drug-eluting in-stent restenosis

BackgroundMechanisms of lumen gain during reinterventions in patients with drug-eluting stent (DES) in-stent restenosis (ISR) remain unsettled. MethodsWe sought to assess the mechanisms of acute lumen gain after balloon angioplasty (BA) and repeat drug-eluting stent (DES) implantation in patients with DES-ISR. Following a prospective protocol 29 consecutive patients with DES-ISR were sequentially treated with BA and new DES implantation under a multimodality intracoronary imaging assessment including intravascular ultrasound (IVUS) and optical coherence tomography (OCT). Imaging studies were systematically obtained, at baseline, after BA, and after DES. Results of interventions were compared using volumetric and morphometric (ISR pattern and injury score) analyses. ResultsIVUS and OCT demonstrated that acute lumen gain after BA and DES equally results from a reduction in intra-stent neointimal volume and further DES expansion. As compared with BA, repeat DES implantation not only increased final lumen (baseline 39.6±18.5mm3, post-BA 58.6±26.6mm3, post-DES 84.2±30.8mm3, all p<0.001) but also provided a smoother lumen (injury score 1.57±0.86 vs 0.22±0.26, p<0.001). At the 9th month of angiographic follow-up (86% patients) in-stent late loss was 0.44±0.5mm and 4 patients (16%) developed ISR. The ISR pattern on OCT was not associated with the injury score after interventions or late angiographic findings. Likewise, the injury score did not predict late angiographic outcome. ConclusionsIn patients with DES ISR, lumen gain equally results from a reduction in intra-stent neointimal volume and further DES expansion. As compared with BA, repeat DES implantation provides a larger and smoother coronary lumen.

Combined coronary lumen and vessel wall magnetic resonance imaging with i-T2prep: influence of nitroglycerin.

It has been shown that sublingual nitroglycerin (NTG) improves image quality of coronary lumen magnetic resonance angiography. Our aim was to investigate the influence of NTG on coronary lumen and vessel wall image quality using a combined, single sequence approach (i-T2prep), which is able to image both within the known time frame of action of NTG. Ten healthy volunteers underwent right coronary artery lumen and vessel wall imaging using the i-T2prep sequence before and after administration of NTG. Image quality was assessed qualitatively and quantitatively. Diameter, length and wall thickness were also measured using dedicated semi-automatic software. NTG induced coronary vasodilatation (lumen diameter increased from 2.16±0.32 to 2.52±0.59mm; p=0.036). As a result, visualized lumen length (9.8±2.6 to 11.4±3.3cm; p=0.025) and qualitative lumen image quality (median 3 (interquartile range 2-3.25) vs. median 3 (interquartile range 3-4); p=0.046) both improved. Vessel wall imaging also demonstrated a significant improvement in vessel wall sharpness after NTG (24.8 vs. 27.3%; p=0.036). This study demonstrates the benefits of NTG for coronary lumen and vessel wall imaging using a combined sequence, i-T2prep. The methodology described here has great potential for future pathophysiological studies.

TCT-273 Coronary Lumen Eccentricity is Associated with Amount of Drug Adhesion after Treatment with Drug Coated Balloon

TCT-273 Coronary Lumen Eccentricity is Associated with Amount of Drug Adhesion after Treatment with Drug Coated Balloon

Molecular imaging of plaques in coronary arteries with PET and SPECT.

Coronary artery disease remains a major cause of mortality. Presence of atherosclerotic plaques in the coronary artery is responsible for lumen stenosis which is often used as an indicator for determining the severity of coronary artery disease. However, the degree of coronary lumen stenosis is not often related to compromising myocardial blood flow, as most of the cardiac events that are caused by atherosclerotic plaques are the result of vulnerable plaques which are prone to rupture. Thus, identification of vulnerable plaques in coronary arteries has become increasingly important to assist identify patients with high cardiovascular risks. Molecular imaging with use of positron emission tomography (PET) and single photon emission computed tomography (SPECT) has fulfilled this goal by providing functional information about plaque activity which enables accurate assessment of plaque stability. This review article provides an overview of diagnostic applications of molecular imaging techniques in the detection of plaques in coronary arteries with PET and SPECT. New radiopharmaceuticals used in the molecular imaging of coronary plaques and diagnostic applications of integrated PET/CT and PET/MRI in coronary plaques are also discussed.

Patterns of Opacification in Coronary CT Angiography: Contrast Differences and Gradients.

Iodinated contrast delivery is a key component of coronary CT angiography. However, the purpose of contrast delivery has been limited to morphology alone. Specifically, iodine opacification of the coronary lumen has been used to separate it from the coronary artery wall and lesions within the coronary arteries. Because contrast is delivered to the coronary arteries according to the coronary blood flow, there is flow information encoded within the contrast opacification which, depending on CT hardware and acquisition protocol, can be recognized in coronary CT angiography. In addition, metrics related to flow have been identified and studied. They include coronary contrast opacification differences and contrast opacification gradients.

Cardiac magnetic resonance and computed tomography angiography for clinical imaging of stable coronary artery disease. Diagnostic classification and risk stratification.

Despite advances in the pharmacologic and interventional treatment of coronary artery disease (CAD), atherosclerosis remains the leading cause of death in Western societies. X-ray coronary angiography has been the modality of choice for diagnosing the presence and extent of CAD. However, this technique is invasive and provides limited information on the composition of atherosclerotic plaque. Coronary computed tomography angiography (CCTA) and cardiac magnetic resonance (CMR) have emerged as promising non-invasive techniques for the clinical imaging of CAD. Hereby, CCTA allows for visualization of coronary calcification, lumen narrowing and atherosclerotic plaque composition. In this regard, data from the CONFIRM Registry recently demonstrated that both atherosclerotic plaque burden and lumen narrowing exhibit incremental value for the prediction of future cardiac events. However, due to technical limitations with CCTA, resulting in false positive or negative results in the presence of severe calcification or motion artifacts, this technique cannot entirely replace invasive angiography at the present time. CMR on the other hand, provides accurate assessment of the myocardial function due to its high spatial and temporal resolution and intrinsic blood-to-tissue contrast. Hereby, regional wall motion and perfusion abnormalities, during dobutamine or vasodilator stress, precede the development of ST-segment depression and anginal symptoms enabling the detection of functionally significant CAD. While CT generally offers better spatial resolution, the versatility of CMR can provide information on myocardial function, perfusion, and viability, all without ionizing radiation for the patients. Technical developments with these 2 non-invasive imaging tools and their current implementation in the clinical imaging of CAD will be presented and discussed herein.

Vulnerable plaque: The biomechanics of matter

Despite the considerable progress that has been made in cardiology over the last four decades through intensive risk-factor modification and life-style changes, cardiovascular disease prevalence, morbidity andmortality remain high [1]. One coronary event occurs every 34 s leading to one death every 83 s in the United States [2]. A significant proportion of these coronary events occur totally unexpectedly in previously asymptomatic individuals and are frequently catastrophic or lead to significant morbidity. In most of the patients with acute coronary events, the culprit lesion is a ruptured atherosclerotic plaque associated with complete or partial atherothrombotic occlusion of the coronary artery lumen. Eroded plaques and plaques with calcified nodules are less frequent causes

Endothelial Cell Heparanase Taken Up by Cardiomyocytes Regulates Lipoprotein Lipase Transfer to the Coronary Lumen After Diabetes

After diabetes, the heart has a singular reliance on fatty acid (FA) for energy production, which is achieved by increased coronary lipoprotein lipase (LPL) that breaks down circulating triglycerides. Coronary LPL originates from cardiomyocytes, and to translocate to the vascular lumen, the enzyme requires liberation from myocyte surface heparan sulfate proteoglycans (HSPGs), an activity that needs to be sustained after chronic hyperglycemia. We investigated the mechanism by which endothelial cells (EC) and cardiomyocytes operate together to enable continuous translocation of LPL after diabetes. EC were cocultured with myocytes, exposed to high glucose, and uptake of endothelial heparanase into myocytes was determined. Upon uptake, the effect of nuclear entry of heparanase was also investigated. A streptozotocin model of diabetes was used to expand our in vitro observations. In high glucose, EC-derived latent heparanase was taken up by cardiomyocytes by a caveolae-dependent pathway using HSPGs. This latent heparanase was converted into an active form in myocyte lysosomes, entered the nucleus, and upregulated gene expression of matrix metalloproteinase-9. The net effect was increased shedding of HSPGs from the myocyte surface, releasing LPL for its onwards translocation to the coronary lumen. EC-derived heparanase regulates the ability of the cardiomyocyte to send LPL to the coronary lumen. This adaptation, although acutely beneficial, could be catastrophic chronically because excess FA causes lipotoxicity. Inhibiting heparanase function could offer a new strategy for managing cardiomyopathy observed after diabetes.

Coronary Artery Disease in Type 1 Diabetic Patients Long-Term After Simultaneous Pancreas and Kidney Transplantation Compared With Live Donor Kidney Transplantation Alone.

Background and aimsImproved long-term glycaemic control protects against development of cardiovascular disease and death in type 1 diabetic patients. We aimed to determine whether long-term normoglycaemia, as achieved by successful pancreas and kidney transplantation (SPK), would change the development of coronary artery disease (CAD) compared with successful live donor kidney transplantation alone (KTA). Materials and methodsTwenty-five type 1 diabetic patients who had received SPK grafts were compared with eighteen recipients of KTA (17 received kidneys from live donors). At follow-up the patients underwent coronary angiography, computed tomography (CT) examination to obtain coronary artery calcium scoring (CACS). ResultsRecipients of SPK grafts and KTA were similar in terms of age and diabetes duration at engraftment. Median length of follow-up was 10.1 (7.2, 20.5) years. HbA1c was 5.6±0.4 % and 8.5±1.8 % in the SPK and KTA group, respectively (p<0.001). At follow-up there was no difference in coronary artery lumen narrowing between the groups. Twenty out of twenty-one (95%) SPK and sixteen out of eighteen (89%) KTA recipients had coronary irregularities (p=0.59). Among those, thirteen (65%) SPK and eight (50%) KTA recipients (p=0.28) had significant coronary artery stenosis (>50% diameter stenosis). Median (range) Agatston score of coronary arteries with CT scan was 1766.5 (9, 7368) and 1003.5 (4, 5897) for the SPK and LDK groups, respectively (p=0.54). There was no significant correlation (OR 1.000, CI 1.000, 1.001; p=0.080) between high CACS and coronary lumen narrowing (>50% diameter stenosis). Conclusion The appearance of CAD as judged by coronary angiography as well as CACS was similar in SPK recipients compared with LDK recipients in spite of more than median 10 years with normoglycaemia in the SPK group. This pilot study may suggest that normoglycaemia is not sufficient to halt or reverse CAD in diabetic patients after transplantation.

THE POSSIBILITIES OF COMPUTED TOMOGRAPHY IN DIAGNOSE OF THE STATE OF CORONARY ARTERIES IN PATIENTS WITH ISCHEMIC HEART DISEASE

This research was aimed to study the possibilities of multislice computed (MSCT) tomography to diagnose status of coronary arteries at the patients with ischemic heart diseases. Material and methods. The research includes the results of complex study of 70 patients, which were send to the cardiology department for the verification of ischemic heart disease, as well as for examination and correction of provided therapy at this category. All patients had been provided traditional invasive coronary angiography and MSCT of coronary arteries. Results. At the 29 (76,3%) patients of 1 group stenosis of coronary arteries were not revealed, in 6 (15,8%) patients were revealed insignificant hemodynamic stenosis. In 3 (7,9%) patients revealed significant hemodynamic stenosis and in 1 (2,6%) critical stenosis (narrowing coronary artery lumen КА &gt; 90 %). By data of MSCT and coronary angiography was revealed strong correlative relationship in diagnosis of stenosis. These factors argue about high comparability of both methods. The greatest correlation relationship was revealed for trunk of left coronary artery, right descending artery and circumflex artery and was 9,2; 0,84 and 0,81 accordingly. Analogical indexes were less for the right coronary artery and was 0,71. Though, large part of the patients in main group was not needed in intracoronary intervention and surgical revascularization. Conclusion. MSCT can use as noninvasive alternative method of coronary angiography in patients with high risk of ischemic heart disease. Comparative analysis of MSCT of coronary arteries and invasive coronary angiography revealed that MSCT has sensitivity of 91%, specificity of 89%.

Corelation between glucose level, lipid profile and risk of coronary heart disease associated with organophosphorus pesticide poisoning

The aim of our research was to correlate blood glucose and serum lipid profile parameters with risk of coronary heart disease associated with organophosphorus pesticide poisoning. For the purpose of this, 50 patients of organophosphorus poisoning and 50 healthy controls were selected. Blood glucose and serum lipid profiles were estimated by using commercially available diagnostic kits. We found a significant decrease (p < 0.05) in serum TAG, serum HDL cholesterol and serum VLDL cholesterol. On other hand we found a significant increase (p < 0.05) in blood glucose, serum total cholesterol and serum VLDL cholesterol. Organophosphorus poisoning is also associated with increased free radical production. Free radicals oxidize LDL cholesterol and oxidized cholesterol is taken by macrophages to form foam cells. Foam cells are responsible for formation of atherosclerotic plaques. Such plaques reduce coronary artery lumen and thus blood supply to heart get reduced which enhances the chances of myocardial infarction. Here, decreased HDL and VLDL and increased LDL cholesterol in organophosphorus poisoning is associated with increased risk of coronary heart diseases. Hence, estimation of blood glucose and lipid profile play important role in the diagnosis of risk of coronary heart diseases in organophosphorus poisoning.

Coronary Intravascular Ultrasound (IVUS): Contemporary Applications and Bases for the Future

Despite the great innovations of non-invasive coronary imaging, coronary angiography still remains the gold standard for the assessment of coronary artery disease (CAD), even if with several limitations. In fact visual assessment of coronary stenosis is convenient and rapid, but often associated with large inter and intra-observer variability, above all in the setting of unstable CAD with complex lesions. Coronary intravascular ultrasound (IVUS) allows accurate tomographic assessment of the coronary lumen and wall. IVUS has several diagnostic applications and is useful for choosing the most appropriate interventional strategy as well as for optimizing percutaneous coronary interventions (PCI) results. The present review focuses on: (1) the role of IVUS to guide therapeutic strategies in complex lesions requiring PCI, (2) IVUS capacity to interrogate borderline coronary stenoses, (3) new perspectives and recent patents for the future of IVUS technology. Keywords: Coronary artery disease, intravascular ultrasound, IVUS, percutaneous coronary intervention, virtual histology IVUS.