Intravascular Ultrasound Imaging Research Articles

Progression of ultrasound plaque attenuation and low echogenicity associates with major adverse cardiovascular events.

Intravascular ultrasound (IVUS) imaging can visualize vulnerable plaque features including attenuation (AP) and echolucency (ELP). While IVUS-derived vulnerable plaque features associate with microvascular obstruction during percutaneous coronary intervention, the relationship between these plaque features and clinical outcomes has not been established. This analysis aimed to evaluate the association of AP/ELP with cardiovascular events. Serial IVUS imaging was reviewed in 1497 patients, followed for 18-24 months, with coronary artery disease from two clinical trials. Attenuated plaque and ELP were identified to measure each characteristics (AP arc, ELP area, and lengths), which permitted calculation of an AP index (API) and ELP volume. Attenuated plaque/ELP progression was defined as patients with any increase of API or ELP volume on serial imaging. The major cardiovascular events (MACEs) were defined as death, myocardial infarction, stroke, and coronary revascularization. AP or ELP was identified in 282 patients (18.8%) at baseline and 160 (10.7%) patients demonstrated an increase in AP or ELP at follow-up. The incidence of MACE was higher in patients with baseline AP/ELP than those without (8.2% vs. 3.9%, P = 0.002). Patients with AP/ELP progression were more likely to be acute coronary syndrome (41.9 vs. 33.2%, P = 0.03) and have greater baseline percent atheroma volume (40.0% vs. 35.8%, P < 0.001) than those without. On multivariable analysis, AP/ELP progression was more strongly associated with MACE [baseline AP/ELP: hazard ratio (HR) 1.76, 95% confidence interval (CI) 1.05-2.97, AP/ELP progression: HR 2.19, 95% CI 1.24-3.86]. Attenuation/ELP progression was associated with a higher prevalence of cardiovascular events, supporting a potential role for the identification of high-risk vulnerable plaques in patients with coronary artery disease.

Calcification detection using convolutional neural network architectures in Intravascular ultrasound images

&lt;p&gt;Cardiovascular disease is the highest leading to death for Non-Communicable disease. Coronary artery calcification disease is part of cardiovascular disease. The built-in of the plaques and the calcification in the coronary artery inner wall make the blood vessel cross-section area narrow. The standard practice by the radiologists and medical clinical are by visual inspection to detect the calcification in the intravascular ultrasound image. Deep learning is the current image processing methods that have high potential to detect calcification analysis using convolutional neural network architecture and classifiers. To detect the absence of calcification and presence calcification on the intravascular ultrasound image, using k-fold =10, we compared the three types of convolutional neural network architectures and the seven types of classifiers with the provided ground truth from MICCAI 2011. We used two types of images named as Cartesian Coordinates image and polar reconstructed coordinate image. The classifiers such as Support Vector Machine, Discriminant analysis, Ensembles and Error-Correcting Output Codes obtained the perfect result with value one for Area Under Curve and all the performance measure result, accuracy, sensitivity, specificity, positive predictive value and negative predictive value. Area Under Curve for Naïve Bayes classifier is 0.9967 and for Decision Tree classifier is 0.9994, obtained using the polar reconstructed coordinate image for InceptionresNet-V2 architecture.&lt;/p&gt;

Intravascular Ultrasound Imaging-Guided Versus Coronary Angiography-Guided Percutaneous Coronary Intervention: A Systematic Review and Meta-Analysis.

BackgroundIntravascular ultrasound (IVUS) guidance during percutaneous coronary intervention (PCI) offers tomographic images of the coronary vessels, allowing optimization of stent implantation at the time of PCI. However, the long‐term beneficial effect of IVUS over PCI guided by coronary angiography (CA) alone remains under question. We sought to investigate the outcomes of IVUS‐guided compared with CA‐guided PCI.Methods and ResultsWe performed a comprehensive search of PubMed, Medline, and Cochrane Central Register, looking for randomized controlled trials and observational studies that compared PCI outcomes of IVUS with CA. Data were aggregated for the primary outcome measure using the random‐effects model as pooled risk ratio (RR). The primary outcomes were the rate of cardiovascular death, need for target lesion revascularization, occurrence of myocardial infarction, and rate of stent thrombosis. A total of 19 studies met the inclusion criteria, comprising 27 610 patients divided into IVUS (n=11 513) and CA (n=16 097). Compared with standard CA‐guided PCI, we found that the risks of cardiovascular death (RR, 0.63; 95% CI, 0.54–0.73), myocardial infarction (RR, 0.71; 95% CI, 0.58–0.86), target lesion revascularization (RR, 0.81; 95% CI, 0.70–0.94), and stent thrombosis (RR, 0.57; 95% CI, 0.41–0.79) were all significantly lower using IVUS guidance.ConclusionsCompared with standard CA‐guided PCI, the use of IVUS imaging guidance to optimize stent implantation is associated with a reduced risk of cardiovascular death and major adverse events, such as myocardial infarction, target lesion revascularization, and stent thrombosis.

Detecting vulnerable plaque with vulnerability index based on convolutional neural networks

Plaque rupture and subsequent thrombosis are major processes of acute cardiovascular events. The Vulnerability Index is a very important indicator of whether a plaque is ruptured, and these easily ruptured or fragile plaques can be detected early. The higher the general vulnerability index, the higher the instability of the plaque. Therefore, determining a clear vulnerability index classification point can effectively reduce unnecessary interventional therapy. However, the current critical value of the vulnerability index has not been well defined. In this study, we proposed a neural network-based method to determine the critical point of vulnerability index that distinguishes vulnerable plaques from stable ones. Firstly, based on MatConvNet, the intravascular ultrasound images under different vulnerability index labels are classified. Different vulnerability indexes can obtain different accuracy rates for the demarcation points. The corresponding data points are fitted to find the existing relationship to judge the highest classification. In this way, the vulnerability index corresponding to the highest classification accuracy rate is judged. Then the article is based on the same experiment of different components of the aortic artery in the artificial neural network, and finally the vulnerability index corresponding to the highest classification accuracy can be obtained. The results show that the best vulnerability index point is 1.716 when the experiment is based on the intravascular ultrasound image, and the best vulnerability index point is 1.607 when the experiment is based on the aortic artery component data. Moreover, the vulnerability index and classification accuracy rate has a periodic relationship within a certain range, and finally the highest AUC is 0.7143 based on the obtained vulnerability index point on the verification set. In this paper, the convolution neural network is used to find the best vulnerability index classification points. The experimental results show that this method has the guiding significance for the classification and diagnosis of vulnerable plaques, further reduce interventional treatment of cardiovascular disease.

A post-market, multi-vessel evaluation of the imaging of peripheral arteries for diagnostic purposeS comparing optical Coherence tomogrApy and iNtravascular ultrasound imaging (SCAN)

BackgroundIntravascular imaging plays an important part in diagnosis of vascular conditions and providing insight for treatment strategy. Two main imaging modalities are intravascular ultrasound (IVUS) and optical coherence tomography (OCT). The objective of this study was to prove non-inferiority of OCT imaging to IVUS images in matched segments of peripheral vessels in patients with suspected peripheral vascular disease.MethodsThe SCAN study was a prospective, non-inferiority clinical study of matched IVUS and OCT images collected along defined segments of peripheral vessels from twelve subjects (mean age 68 ± 10.3 years; 10 men) displaying symptoms of vascular disease. Luminal diameters were measured by both imaging systems at the distal, middle, and proximal points of the defined segments. Three blinded interventional radiologists evaluated the quality of both imaging modalities in identifying layered structures (3-point grading), plaque (5-point grading), calcification (5-point grading), stent structure (3-point grading), and artifacts (3-point grading) from 240 randomly ordered images. Mean grading scores and luminal diameters were calculated and analyzed with Student’s t-Test and Mann-Whitney-Wilcoxon testing. Intrareader reproducibility was calculated by intraclass correlation (ICC) analysis.ResultsThe mean scoring of plaque, calcification, and vascular stent struts by the three readers was significant better in terms of image quality for OCT than IVUS (p < 0.001, p = 0.001, p = 0.004, respectively). The mean scores of vessel wall component visibility and artifacts generated by the two imaging systems were not significantly different (p = 0.19, p = 0.07, respectively). Mean vessel luminal diameter and area at three specific locations within the vessels were not significantly different between the two imaging modalities. No patient injury, adverse effect or device malfunction were noted during the study.ConclusionsImaging by OCT provides the physician with better visualization of some vessel and plaque chacteristics, but both IVUS and OCT imaging are safe and effective methods of examining peripheral vessels in order to perform diagnostic assessment of peripheral vessels and provide information necessary for the treatment strategy of peripheral artery disease.Trial registrationNCT03480685 registered on 29 March 2018.

The impact of helical flow on coronary atherosclerotic plaque development

Background and aimsAtherosclerosis has been associated with near-wall hemodynamics and wall shear stress (WSS). However, the role of coronary intravascular hemodynamics, in particular of the helical flow (HF) patterns that physiologically develop in those arteries, is rarely considered.The purpose of this study was to assess how HF affects coronary plaque initiation and progression, definitively demonstrating its atheroprotective nature. MethodsThe three main coronary arteries of five adult hypercholesterolemic mini-pigs on a high fat diet were imaged by computed coronary tomography angiography (CCTA) and intravascular ultrasound (IVUS) at 3 (T1, baseline) and 9.4 ± 1.9 (T2) months follow-up. The baseline geometries of imaged coronary arteries (n = 15) were reconstructed, and combined with pig-specific boundary conditions (based on in vivo Doppler blood flow measurements) to perform computational fluid dynamic simulations. Local wall thickness (WT) was measured on IVUS images at T1 and T2, and its temporal changes were assessed. Descriptors of HF and WSS nature were computed for each model, and statistically compared to WT data. ResultsHF intensity was strongly positively associated with WSS magnitude (p < 0.001). Overall, coronary segments exposed to high baseline levels of HF intensity exhibited a significantly lower WT growth (p < 0.05), compared to regions with either mid or low HF intensity. ConclusionsThis study confirms the physiological significance of HF in coronary arteries, revealing its protective role against atherosclerotic WT growth and its potential in predicting regions undergoing WT development. These findings support future in vivo measurement of coronary HF as atherosclerotic risk marker, overcoming current limitations of in vivo WSS assessment.

Spine stabilization is a risk factor for the development of pelvic iliac vein lesions

BackgroundOpen lumbar spine stabilization surgery often requires mobilization of the left and right common iliac veins (CIVs) and the placement of plates and screws that can impinge on them. We reviewed our venography experience of the past 3 years to determine whether there is an association between spine stabilization surgery and the development of symptomatic iliac vein outflow lesions. MethodsA retrospective chart review of prospectively collected data from our electronic medical record system was performed to identify patients who underwent venography with or without venous stenting and had a history of previous lumbar spine stabilization. Patients' demographics, medical comorbidities, venograms, and intravascular ultrasound (IVUS) data were collected and analyzed. The senior author reviewed all venograms and IVUS images of patients with previous spine stabilization procedures. ResultsFrom January 2014 to April 2018, venography was performed in 1713 limbs in 1245 patients at the Center for Vascular Medicine. Of the 1245 patients, 18 patients had a history of lumbar spine stabilization procedures: five anterior-posterior and 13 posterior. Nine had single-level and eight had two- or three-level fusions. All 18 patients demonstrated pelvic lesions. These included 1 left CIV aneurysm, 5 left CIV stenoses, 3 bilateral CIV stenoses, 2 left CIV and inferior vena cava occlusions, and 2 external iliac vein stenoses. The aneurysm patient was treated with anticoagulation, 8 patients underwent stenting, 1 patient refused stenting because of relocation to another country, 1 inferior vena cava-CIV occlusion could not be crossed, fear of dislodging a thrombus and the proximity to a protruding posteriorly placed screw prevented stenting in 2 patients, and 4 patients had a venoplasty alone because of undersizing of a stenosis or missed lesions with IVUS after review by a blinded reviewer. Lesions in anterior lumbar interbody fusion patients were extremely stenotic, required predilation, and resulted in a residual stenosis requiring venoplasty at a second setting in one patient. ConclusionsLumbar spine stabilization surgery may be a risk factor for development of symptomatic venous outflow obstruction lesions. During venography and stenting in patients with anterior lumbar interbody fusion approaches, significant scarring may be encountered, resulting in a residual stenosis after stent placement. Predilation venoplasty, before stent deployment, is recommended to prevent stent migration. Furthermore, a history of spine stabilization surgery in patients presenting with pelvic symptoms, lower extremity pain or swelling, or post-thrombotic symptoms should prompt consideration of a pelvic venous duplex ultrasound examination to determine whether an iliac venous outflow lesion is present.

CRT-300.01 Impact of Near-Infrared Spectroscopy Intravascular Ultrasound Imaging Evaluation on Major Adverse Cardiovascular Events in Patients With Chronic Renal Insufficiency

Chronic renal insufficiency (CRI) was reported as a residual independent risk and prognostic factor of coronary artery disease in the latest drug-eluting stent (DES) era with mature DES technology and developed medical treatment. Near infrared spectroscopy intravascular ultrasound imaging (NIRS-IVUS

Performance Assessment of K-Means and KNN Algorithm for the Detection of Borders and Extraction of Plaque Area from IVUS Images

The coronary artery vascular disease of atherosclerosis, which made the blood vessel artery wall harden and narrow. The vascular wall disease quantitatively analyzed and diagnosed by an intravascular ultrasound (IVUS) image. The quantitative investigations of coronary atherosclerosis by means of IVUS and manual recognition of wall and plaque borders are restricted by the need for observers with considerable understanding and the tedious environment of manual border detection. To improve and provide more detailed vessel and plaque information for better diagnosis and assessment go for an automated segmentation. An automated construction for the purpose of perceiving lumen and media-adventitia borders in IVUS images was effectively formulated. An effectual unsupervised K-Means clustering scheme refine the borders with morphological operations, later an IVUS data samples area classified using supervised KNN(K-Nearest Neighbor) classifier to extract the plaque feature. The performance of contour metric measurements in terms of Jaccard Index (JI), percentage area difference (PAD), area error (AE), dice index (DI), false positive ratio (RFP), in addition to false negative ratio (RFN) are computed for evaluation and variation.

Lipid-rich large plaques in a non-culprit left main coronary artery and long-term clinical outcomes.

An integrated backscatter (IB) intravascular ultrasound (IVUS) provides an information about tissue components and vulnerability of coronary plaques. The presence of vulnerable plaque in non-culprit lesion is associated with future clinical events. The purpose of this study was to assess the association between the characteristics of non-culprit left main coronary artery (LMCA) plaques evaluated by IB-IVUS and long-term clinical outcomes in patients undergoing percutaneous coronary intervention (PCI). Among the patients who underwent non-LMCA PCI, we studied 366 patients with adequate LMCA IVUS images. Conventional and IB-IVUS analyses of the LMCA segment were performed. Lipid-rich large plaque was defined as the presence of both a lager plaque volume and a higher percentage of the lipid component than the obtained median values. Major adverse cardiovascular events (MACE) included cardiac death, myocardial infarction, and unplanned revascularization. The mean age of the patients was 68.5±10.2years, 79.8% were men. Median follow-up period was 6.0years (IQR: 4.2-8.1years). The incidence of MACE was significantly higher in patients with lipid-rich large plaques (P=.006). The incidence rates of cardiac death, myocardial infarction, and unplanned revascularization were significantly higher in patients with lipid-rich large plaques (P=.02, 0.004, and 0.02, respectively). Multivariate Cox regression analysis showed that the presence of a lipid-rich large plaque was significantly associated with MACE (HR: 1.74; 95%CI: 1.17-2.58; P=.006). The presence of lipid-rich large plaques in a non-culprit LMCA can be associated with the long-term MACE in patients who have undergone PCI.

Intravascular ultrasound imaging for the optimization of dialysis access interventions.

Intravascular ultrasound allows for detailed imaging of the dialysis access anatomy. Accurate visualization and precise measurements of the anatomy can be obtained using intravascular ultrasound, while limiting contrast usage and radiation exposure. Intravascular ultrasound allows for a true appreciation of stenosis morphology and can further guide endovascular management decisions, with a particular benefit in management of central venous lesions. Here, we describe a series of cases that together highlight the advantages of using intravascular ultrasound in the evaluation and management of dialysis access care.

Vessel membrane segmentation and calcification location in intravascular ultrasound images using a region detector and an effective selection strategy

Background and objectiveSegmenting vessel membranes and locating the calcific region in intravascular ultrasound (IVUS) images aid physicians in the diagnosis of atherosclerosis. However, the manual extraction of the media adventitia (MA)/lumen border and calcification location are cumbersome due to the excessive number of IVUS frames. Moreover, most existing (semi-)automatic detection methods cannot achieve both vessel membrane extraction and calcification location simultaneously, and they are unable to detect vessel membranes in IVUS frames from different acquisition systems. MethodA fully automatic approach is proposed based on extremal regions and a flexible selection strategy to extract vessel membranes in different IVUS frames and locate the calcific region in high-frequency ones. Three main steps are included in the algorithm. First, a region detector is employed to extract extremal regions from an IVUS image. Then, according to the selection strategy, a part of the extracted regions is selected. At the same time, the calcification is located according to its special acoustic properties. Next, approximate MA and lumen border segmentation is achieved based on the selected extremal regions and the located calcification in polar coordinates. Finally, the final segmentation results are obtained by smoothing the approximate values. ResultTo demonstrate the feasibility of the method, it was evaluated based on a standard public dataset. Furthermore, to quantitatively evaluate the segmentation performance, the Hausdorff distance (HD), Jaccard measure (JM) and percentage of area difference (PAD) were used. The results show that a mean HD of 1.13/1.21 mm, a mean JM of 0.83/0.77 and a mean PAD of 0.11/0.23 are achieved for MA/lumen border detection in 77 40-MHz IVUS images. For MA/lumen border extraction in 435 20-MHz IVUS frames, the average HD, JM and PAD values are 0.47/0.28 mm, 0.84/0.89 and 0.13/0.10, respectively. In addition, the approach successfully achieves calcification location in 40-MHz IVUS frames. In comparison with other published methods, the method proposed in this study is competitive. ConclusionAccording to these results, our strategy can extract MA/lumen borders in different IVUS frames and effectively locate calcification in high-frequency IVUS frames.

Visibility of Bioresorbable Vascular Scaffold in Intravascular Ultrasound Imaging.

Bioresorbable vascular scaffold (BVS) has recently been spotlighted for its unique characteristics of absorbing into blood vessels and eventually disappearing. Although intravascular ultrasound (IVUS) is the most common guiding tool for stent deployment, the echogenicity of BVS struts has changed as the center of stent lumen and scanning rotation is not concentric, which may cause a critical erroneous measurement in practice. This study investigated the physical conditions for dimming the stent brightness in IVUS images using a finite-difference method (FDM) to numerically solve acoustic wave propagation through nonhomogeneous medium. The dimmed brightness is caused by an angled rectangular cross section of a strut and its similar acoustic impedance with water. Imaging frequency is not a major cause. However, the angle between the acoustic beam and the BVS surface is the major cause of the dimmed brightness. As a solution, an approach using a frequency compounding method with signal polarity comparator was proposed to recover the reduced brightness without sacrificing spatial resolutions. Based on the simulation study, the signal level from BVS can be attenuated down by 17 dB when the angle between the acoustic beamline and the surface of BVS is more than 45°. With the proposed frequency compounding approach, the reduced signal can be recovered by 6 dB. In the experimental BVS IVUS imaging, strut brightness was reduced by 18 dB with an angled strut position and recovered by 5 dB with the proposed frequency compounding method. A pig coronary was imaged to demonstrate the performance of the proposed method.

Black-pooling sign: A novel intravascular ultrasound imaging marker that predicts stent edge hematoma growth.

Black-pooling sign: A novel intravascular ultrasound imaging marker that predicts stent edge hematoma growth.

Coronary artery ectasia in acute myocardial infarction: To be culprit or not to be?

Coronary artery ectasia (CAE), is found in only 1% of acute myocardial infarction (AMI), but is a clinical challenge for percutaneous coronary intervention (PCI) of the culprit artery. Purpose We aim to assess the impact of CAE as culprit artery on management strategy. From 2010 to 2019, we analyzed the characteristics, and management of 70 consecutive patients admitted for an AMI with CAE at coronary angiography. Patients with ectatic infarcted-related artery (ERIA) were compared with patients without ectasia on infarcted-related (No ERIA). Most (67%) had ERIA. ERIA patients had more frequently diabetes (32 vs. 4%, P = 0.01). The rate of other CV risk factors, and chronic medications, including antiplatelet agents and anticoagulants were similar for the 2 groups. Moreover, no difference was observed between the 2 groups for clinical parameters and biological data. Whatever the group, the ectatic artery is mainly located on the right coronary artery (RCA) (73%), of which most were ERIA (77%). ERIA group had less frequently anterior wall location STEMI (18 vs. 65%, P < 0.001). The rate of diffuse coronary artery disease (91 vs. 92%) and maximum CAE diameter (6.36 (6.00–7.00) mm vs. 6.14 (5.53–7.64) mm, P = 0.571) were similar for the 2 groups. SYNTAX was lower in ERIA patients (9.5 (2.0–18.0) vs. 13.5 (7.0–23.0), P = 0.031). A complete reperfusion was more frequently achieved in no ERIA group (70vs47%, P = 0.073) ( Table 1 ). CAE management is strongly dependent on the presence of CAE on IRA. Although rare, the optimal treatment strategy of patients with AMI and CAE remains to be elucidated. The place of intravascular ultrasound imaging needs to be investigated.

Automated classification of dense calcium tissues in gray-scale intravascular ultrasound images using a deep belief network

BackgroundIVUS is widely used to quantitatively assess coronary artery disease. The purpose of this study was to automatically characterize dense calcium (DC) tissue in the gray scale intravascular ultrasound (IVUS) images using the image textural features.MethodsA total of 316 Gy-scale IVUS and corresponding virtual histology images from 26 patients with acute coronary syndrome who underwent IVUS along with X-ray angiography between October 2009 to September 2014 were retrospectively acquired and analyzed. One expert performed all procedures and assessed their IVUS scans. After image acquisition, the DC candidate and corresponding acoustic shadow regions were automatically determined. Then, nine image-base feature groups were extracted from the DC candidates. In order to reduce the dimensionalities, principal component analysis (PCA) was performed, and selected feature sets were utilized as an input for a deep belief network. Classification results were validated using 10-fold cross validation.ResultsThe dimensionality of the feature map was efficiently reduced by 50% (from 66 to 33) without any performance decrease using PCA method. Sensitivity, specificity, and accuracy of the proposed method were 92.8 ± 0.1%, 85.1 ± 0.1%, and 88.4 ± 0.1%, respectively (p < 0.05). We found that the window size could largely influence the characterization results, and selected the 5 × 5 size as the best condition. We also validated the performance superiority of the proposed method with traditional classification methods.ConclusionsThese experimental results suggest that the proposed method has significant clinical applicability for IVUS-based cardiovascular diagnosis.

Plaque Mass Border Detection and Classification in Intravascular Ultrasound Images Using Plaque Mass Weight-K-Nearest Neighbour Classifier

Plaque Mass Border Detection and Classification in Intravascular Ultrasound Images Using Plaque Mass Weight-K-Nearest Neighbour Classifier

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Intravascular ultrasound findings and stent implantation for a patient with coronary spastic angina at site of progressive atherosclerotic plaque and responded poorly to medical treatment: a case report

BackgroundMost coronary spastic angina patients are responsive to coronary vasodilators therapy, and stent implantation is not recommended for regular use. We reported the angiographic and intravascular ultrasound (IVUS) images of a rare case who responded poorly to medical treatment due to progressive atherosclerotic plaque at the spastic site.Case presentationA 60-year-old man complaining of 1-month history of episodic chest pain at rest was admitted to our hospital. The diagnosis of coronary spastic angina was made based on the angiographic evidence of vasospasm at the right coronary artery (RCA). The patient responded poorly to conventional medical treatment during the 1-year follow-up. The repeated angiography revealed totally occlusion of the proximal segment of the RCA at the same location as 1 year before, and IVUS demonstrated there was vulnerable plaque and thrombus at the site of spasm. Episodic chest pain ceased completely in the follow up period after stenting.ConclusionCoronary spasm might present at the vessel site with advanced atherosclerotic plaque. For patients with refractory vasospastic angina and significant occlusion, stenting might be a viable and valuable treatment strategy under the guidance of intracoronary imaging.

In vivo measurement of stent length by using intravascular ultrasound

BackgroundWhat happens to stent length when deployed in a coronary artery? It is the aim of this study.ResultsConsecutive 95 balloon-expandable stents (BES) were studied by intravascular ultrasound (IVUS) imaging. The stent length was measured from the longitudinal view in two ways: (1) edge-to-edge length (E-E) measured between distal and proximal stent frames located at one IVUS quadrant and (2) area-to-area length (A-A) measured between distal and proximal stent frames located at two or more IVUS quadrants. IVUS measurements were compared with the manufacturer-stated length (M-L). The median E-E length was significantly longer than M-L, 18.76 mm [interquartile range (IQR) 15.65–23.60] versus 18.00 mm (IQR 15.00–23.00), respectively, p < 0.0001. Also, the median A-A length was significantly longer, 18.36 mm (IQR 15.19–23.47), p < 0.0001, than M-L. Moreover, the E-E length was significantly different from A-A length, p < 0.0001. Among the stent groups, the differences were significantly present in all drug-eluting stent and bare metal stent (BMS) comparisons, p < 0.0001, except the A-A length versus M-L in BMS only. By multivariate analysis, the predictors of difference in stent length were as follows: lesion length, p = 0.01; pre-intervention minimal diameter of the external elastic membrane (EEM), p = 0.03; lesions present in the left anterior descending branch, p = 0.03; and M-L, p = 0.04.ConclusionsIn the present study, the length of BES measured by IVUS was significantly different from the manufacturer-stated length. In addition to the manufacturer length, other important factors such as lesion length, pre-intervention diameter of EEM, and affected vessel determine the stent length.