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Background: Segmental postpercutaneous coronary intervention (PCI) pressure gradients may detect residual disease and potential targets for optimization. However, universal definitions of relevant segmental gradients are lacking., Objectives: This study sought to evaluate the diagnostic performance of post-PCI fractional flow reserve (FFR), distal coronary pressure-to-aortic pressure ratio (Pd/Pa), and diastolic pressure ratio (dPR) gradients to detect residual focal lesions and stent underexpansion as observed by intravascular ultrasound (IVUS)., Methods: Patients from the IVUS-guided optimization arm of the FFR REACT (FFR-guided PCI Optimization Directed by High-Definition IVUS Versus Standard of Care) trial with complete IVUS and FFR pullback data were included. Patients with angiographically successful PCI and post-PCI FFR <0.90 underwent FFR, Pd/Pa, and IVUS pullbacks. dPR was calculated offline using dedicated software. Segmental pressure gradients (distal, in stent, and proximal) in segments ≥5 mm were evaluated against IVUS-detected residual disease (distal or proximal focal lesions and stent underexpansion)., Results: A total of 139 vessels were included (mean post-PCI FFR: 0.83 ± 0.05, range 0.56-0.89). Focal distal and proximal lesions were detected by IVUS in 23 (17.4%) of 132 and 14 (12.6%) of 111 vessels, respectively, whereas stent underexpansion was present in 86 (61.9%) vessels. Diagnostic ability of segmental FFR gradients to predict IVUS-detected distal and proximal lesions was moderate-to-good (area under the curve [AUC]: 0.69 and 0.84, respectively) and poor to moderate for segmental Pd/Pa and dPR gradients (AUC ranging from 0.58 to 0.69). In-stent gradients had no discriminative ability to detect stent underexpansion (FFR AUC: 0.52; Pd/Pa AUC: 0.54; dPR AUC: 0.55)., Conclusions: In patients with post-PCI FFR <0.90, segmental post-PCI pressure gradients have moderate discriminative ability to identify IVUS-detected focal lesions but no discriminative ability to identify IVUS-detected stent underexpansion., Competing Interests: Funding Support and Author Disclosures The Erasmus Medical Center received institutional research support from ACIST Medical Systems, Inc. Ms Neleman and Dr Diletti have received institutional grant support from ACIST Medical Systems. Dr Van Mieghem has received institutional research grant support from Abbott Vascular, Boston Scientific, Edwards Lifesciences, Medtronic, Daiichi Sankyo, PulseCath BV, and Abiomed. Dr Daemen has received institutional grant/research support from Abbott Vascular, Boston Scientific, ACIST Medical Systems, Medtronic, Pie Medical, and ReCor medical; and received consulting and lecture fees from Abbott Vascular, Abiomed, ACIST Medical Systems, Boston Scientific, Cardialysis BV, CardiacBooster, Kaminari Medical, ReCor Medical, PulseCath, Pie Medical, Sanofi, Siemens Health Care and Medtronic. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2023. Published by Elsevier Inc.)

Background: Severe coronary artery calcification is associated with stent underexpansion and subsequent stent failure., Aims: We aimed to identify optical coherence tomography (OCT)-derived predictors of absolute (minimal stent area [MSA]) and relative stent expansion in calcified lesions., Methods: This retrospective cohort study included patients who underwent percutaneous coronary intervention (PCI) with OCT assessment before and after stent implantation between May 2008 and April 2022. Pre-PCI OCT was used to assess calcium burden and post-PCI OCT was used to assess absolute and relative stent expansion., Results: A total of 361 lesions in 336 patients were analyzed. Target lesion calcification (defined as OCT-detected maximum calcium angle ≥ 30°) was present in 242 (67.0%) lesions. Following PCI, median MSA was 5.37 mm 2 in calcified lesions and 6.24 mm 2 in noncalcified lesions (p < 0.001). Median stent expansion was 78% in calcified lesions and 83% in noncalcified lesions (p = 0.325). In the subset of calcified lesions, average stent diameter, preprocedural minimal lumen area, and total calcium length were independent predictors of MSA in multivariable analysis (mean difference 2.69 mm 2 /mm 2 , 0.52 mm 2 /mm, and -0.28 mm 2 /5 mm, respectively, all p < 0.001). Total stent length was the only independent predictor of relative stent expansion (mean difference -0.465% per mm, p < 0.001). Calcium angle, thickness, and the presence of nodular calcification were not significantly associated with MSA or stent expansion in multivariable analyses., Conclusion: Calcium length appeared to be the most important OCT-derived predictor of MSA, whereas stent expansion was mainly determined by total stent length., (© 2023 The Authors. Catheterization and Cardiovascular Interventions published by Wiley Periodicals LLC.)

Lesion calcification is frequently encountered during percutaneous coronary intervention and has been directly linked to procedural complications and future cardiac events. Intravascular lithotripsy is a novel balloon-based modality that does not rely on barotrauma or debulking, but converts electrical energy into mechanical energy creating sonic pressure waves that selectively disrupt calcium. The present review provides an overview of its mechanism of action, the available evidence on its safety and efficacy and indications for use., Competing Interests: Declaration of Competing Interest Joost Daemen received institutional grant/research support from Astra Zeneca, Abbott Vascular, Boston Scientific, ACIST Medical Systems, Medtronic, Pie Medical, and ReCor Medical. The remaining authors have nothing to disclose., (Copyright © 2022. Published by Elsevier Inc.)

Background: Complete revascularization in patients with ST-segment elevation myocardial (STEMI) improves clinical outcome. Vessel fractional flow reserve (vFFR) has been validated as a non-invasive physiological technology to evaluate hemodynamic lesion significance without need for a dedicated pressure wire or hyperemic agent. This study aimed to assess discordance between vFFR reclassification and treatment strategy in intermediate non-culprit lesions of STEMI patients and to assess the clinical impact of this discordance., Methods: This was a single-center, retrospective cohort study. From January 2018 to December 2019, consecutive eligible STEMI patients were screened based on the presence of a non-culprit vessel with an intermediate lesion (30-80% angiographic stenosis) feasible for offline vFFR analysis. The primary outcome was the percentage of non-culprit vessels with discordance between vFFR and actual treatment strategy. The secondary outcome was two-year vessel-oriented composite endpoint (VOCE), a composite of vessel-related cardiovascular death, vessel-related myocardial infarction, and target vessel revascularization., Results: A total of 441 patients (598 non-culprit vessels) met the inclusion criteria. Median vFFR was 0.85 (0.73-0.91). Revascularization was performed in 34.4% of vessels. Discordance between vFFR and actual treatment strategy occurred in 126 (21.1%) vessels. Freedom from VOCE was higher for concordant vessels (97.5%) as compared to discordant vessels (90.6%)(p = 0.003), particularly due to higher adverse event rates in discordant vessels with a vFFR ≤0.80 but deferred revascularization., Conclusions: In STEMI patients with multivessel disease, discordance between vFFR reclassification and treatment strategy was observed in 21.1% of non-culprit vessels with an intermediate lesion and was associated with increased vessel-related adverse events., Competing Interests: Declaration of Competing Interest Nicolas Van Mieghem received institutional research grant support from Abbott Vascular, Abiomed, Boston Scientific, Daiichi-Sankyo, Edward Lifesciences, Medtronic, and PulseCath. Joost Daemen received institutional grant/research support from Abbott Vascular, ACIST Medical, Astra Zeneca, Boston Scientific, Medtronic, Pie Medical, and ReCor Medical. The remaining authors report no relationships that could be construed as a conflict of interest., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: In order to facilitate fractional flow reserve (FFR)-guided lesion assessment, several 3-dimensional (3D)-angiography-based physiological indices have been recently validated. Thus far, limited data are available on the association of these indices with conventional forms of ischemia testing., Aim: The aim of the study was to determine the association between 3D-angiography-based vessel-FFR (vFFR) and myocardial ischemia as assessed by exercise electrocardiography (ECG) testing, dobutamine stress echocardiography, single photon emission computed tomography myocardial perfusion imaging (SPECTMPI), and stress cardiovascular magnetic resonance imaging (stress CMR)., Methods: FAST ISCHEMIA is a retrospective, single-center cohort study including patients who underwent non-invasive myocardial ischemia testing and subsequent coronary angiography (≤3 months). A total of 145 patients (340 vessels) were analyzed. The overall patient-based sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+), and negative likelihood ratio (LR-) of vFFR ≤0.80 in any vessel for ischemia was 64% (95% confidence interval [CI], 53-74), 71% (95% CI, 54-84), 83% (95% CI, 72-91), 46% (95% CI, 33-60), 2.16 (95% CI, 1.25-3.74), and 0.52 (95% CI, 0.36-0.74), respectively. Multivariable logistic regression showed that vFFR ≤0.80 was significantly associated with ischemia on a patient level (odds ratio, 8.13; 95% CI, 2.51-30.06; P<.001) and on a vascular territory level (odds ratio, 2.75; 95% CI, 1.17-6.44; P<.01)., Conclusion: Our study suggests that vFFR ≤0.80 has a modest association with non-invasive myocardial ischemia testing using either exercise ECG or stress imaging modalities. After correcting for independent confounders, vFFR was independently associated with ischemia on a non-invasive myocardial ischemia detection test.

Objective: Thinner stent struts might lead to a higher risk of recoil and subsequently a smaller minimal stent area (MSA), which is known to be the strongest predictor of stent failure. We compared procedural performance between an ultrathin-strut biodegradable-polymer sirolimus-eluting stent (BP-SES) and a durable-polymer zotarolimus-eluting stent (DP-ZES) using intracoronary imaging., Methods: A consecutive cohort of patients underwent percutaneous coronary intervention (PCI) with either BP-SES or DP-ZES in a pseudorandomized fashion between July 2018 and October 2019. In the present subanalysis, we included cases in which post-PCI imaging with intravascular ultrasound (IVUS) or optical coherence tomography (OCT) was performed. The primary endpoint of the study was MSA. Secondary endpoints included percentage stent expansion and presence of residual edge disease, malapposition, tissue protrusion, submedial edge dissections, or edge hematoma., Results: A total of 141 treated lesions (78 BP-SES and 63 DP-ZES) in 127 patients were analyzed. Median age was 69.3 years (interquartile range [IQR], 57.3-75.6) and 74.0% of patients were male. All baseline and procedural characteristics were comparable between both groups. Median MSA was 5.80 mm² (IQR, 4.40-7.24) for BP-SES and 6.35 mm² (IQR, 4.76-8.31) for DP-ZES (P=.15). No significant differences in stent expansion, residual edge disease and presence of malapposition, tissue protrusion, submedial edge dissections, or edge hematomas were found. Stent diameter and stent length were found to be independent predictors of MSA., Conclusions: No significant differences in MSA were found between lesions treated with BP-SES vs DP-ZES. BP-SES and DP-ZES were comparable in terms of procedural performance.

Background: Angiography-based vessel fractional flow reserve (vFFR) demonstrated a strong correlation with invasive fractional flow reserve (FFR) in both a pre- and post-percutaneous coronary intervention (PCI) setting. However, the role of vFFR and its correlation with post-PCI FFR in chronic coronary occlusions (CTO) has not been evaluated yet. We sought to investigate the diagnostic performance of post-PCI vFFR with post-PCI FFR as a reference in patients undergoing successful CTO PCI., Methods: Between March 2016 and April 2020, a total of 80 patients from the FFR-SEARCH (prospective registry) and FFR REACT (randomized controlled trial) studies underwent successful CTO recanalization with post-PCI FFR measurements., Results: A total of 50 patients (median age 66 (interquartile range [IQR]: 56-74) years, 76% were male) were eligible for the analysis. Median post-PCI FFR was 0.89 (IQR: 0.84-0.94), while median post-PCI vFFR was 0.91 (IQR: 0.85-0.94) (p 0.10). Suboptimal physiological results, defined as FFR and vFFR <0.90, were identified in 26 (52%) and in 21 (42%) patients, respectively. A strong correlation (r = 0.82) was found between vFFR and FFR with a mean bias of 0.013 ± 0.051. Receiver-operating characteristics curve analysis revealed an excellent accuracy of vFFR in predicting FFR <0.90 (area under the curve: 0.97; 95% confidence interval: 0.93-1.00)., Conclusion: Post-PCI vFFR shows a good correlation with post-PCI FFR and a high diagnostic accuracy for post-PCI FFR ≤0.90 in patients undergoing successful PCI of a CTO lesion., (© 2022 The Authors. Catheterization and Cardiovascular Interventions published by Wiley Periodicals LLC.)

Objectives: To validate a simplified core laboratory intravascular ultrasound (IVUS) analysis method based on frames with visually determined minimal lumen areas (MLAs) as compared with a comprehensive (per frame) analysis method., Background: IVUS-guided percutaneous coronary intervention has proven to be superior to angiography-guided stenting. In clinical practice, cross-sections with visually determined MLA are measured to determine lesion severity or minimal stent area (MSA), however, its accuracy has not been compared with a comprehensive per frame analysis method., Methods: A total of 50 stented coronary segments of anonymized core lab datasets were analyzed using a comprehensive analysis method and reanalyzed by two core lab analysts using the simplified method including a maximum of seven frames to be analyzed (the visually determined MSA, the first and last frame, and the MLA of each reference segment). The main parameters of interest were MSA, MLA in the reference segments, and plaque burden., Results: The simplified method showed moderate agreement for measurement of the proximal MLA (7.51 ± 2.52 vs. 6.32 ± 1.88 mm 2 , intraclass correlation coefficient [ICC] = 0.73), good agreement for the distal MLA (5.41 ± 1.85 vs. 5.11 ± 1.38 mm 2 , ICC = 0.84) and plaque burden proximal (0.49 ± 0.12 vs. 0.50 ± 0.11, ICC = 0.88), and excellent agreement for the MSA (5.35 ± 1.05 vs. 5.32 ± 0.99 mm 2 , ICC = 0.94) and plaque burden distal (0.47 ± 0.14 vs. 0.47 ± 0.12, ICC = 0.92), when compared with the comprehensive analysis method. Inter- and intraobserver analysis revealed good-to-excellent agreement for all parameters., Conclusions: Measuring poststenting IVUS cross-sections with visually determined MLAs by experienced core lab analysts is an accurate and reproducible method to identify MLAs., (© 2022 The Authors. Catheterization and Cardiovascular Interventions published by Wiley Periodicals LLC.)

Background: Post-percutaneous coronary intervention (PCI) fractional flow reserve (FFR) <0.90 is common and has been related to impaired patient outcome., Objectives: The authors sought to evaluate if PCI optimization directed by intravascular ultrasound (IVUS) in patients with post-PCI FFR <0.90 could improve 1-year target vessel failure (TVF) rates., Methods: In this single-center, randomized, double-blind trial, patients with a post-PCI FFR <0.90 at the time of angiographically successful PCI were randomized to IVUS-guided optimization or the standard of care (control arm). The primary endpoint was TVF (a composite of cardiac death, spontaneous target vessel myocardial infarction, and clinically driven target vessel revascularization) at 1 year., Results: A total of 291 patients with post-PCI FFR <0.90 were randomized (IVUS-guided optimization arm: n = 145/152 vessels, control arm: n = 146/157 vessels). The mean post-PCI FFR was 0.84 ± 0.05. A total of 104 (68.4%) vessels in the IVUS-guided optimization arm underwent additional optimization including additional stenting (34.9%) or postdilatation only (33.6%), resulting in a mean increase in post-PCI FFR in these vessels from 0.82 ± 0.06 to 0.85 ± 0.05 (P < 0.001) and a post-PCI FFR ≥0.90 in 20% of the vessels. The 1-year TVF rate was comparable between the 2 study arms (IVUS-guided optimization arm: 4.2%, control arm: 4.8%; P = 0.79). There was a trend toward a lower incidence of clinically driven target vessel revascularization in the IVUS-guided optimization arm (0.7% vs. 4.2%, P = 0.06)., Conclusions: IVUS-guided post-PCI FFR optimization significantly improved post-PCI FFR. Because of lower-than-expected event rates, post-PCI FFR optimization did not significantly lower TVF at the 1-year follow-up., Competing Interests: Funding Support and Author Disclosures The Erasmus Medical Center received institutional research support from ACIST Medical Systems, Inc. Dr Diletti has received institutional research grant support from ACIST Medical Systems, Inc. Dr Van Mieghem has received institutional research grant support from Abbott Vascular, Boston Scientific, Edwards Lifesciences, Medtronic, Daiichi-Sankyo, PulseCath BV, and Abiomed. Dr Daemen has received institutional grant/research support from AstraZeneca, Abbott Vascular, Boston Scientific, ACIST Medical Systems, Inc, Medtronic, Pie Medical, and ReCor medical. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Vessel Fractional Flow Reserve (vFFR) as assessed by three-dimensional quantitative coronary angiography has high correlation with pressure wire-based fractional flow reserve in both a pre- and post-PCI setting. The present study aims to assess the prognostic value of post-PCI vFFR on the incidence of target vessel failure (TVF), a composite endpoint of cardiac death, target vessel myocardial infarction and target vessel revascularization (TVR) at 5-year follow up., Methods: Post-PCI vFFR was calculated after routine PCI in a total of 748 patients (832 vessels) with available orthogonal angiographic projections of the stented segment., Results: Median age was 65 (IQR 55-74) years, 18.2% were diabetic, and 29.1% presented with stable angina. Median post-PCI vFFR was 0.91 (IQR 0.86-0.95). Vessels were categorized into tertiles based on post-PCI vFFR: low (vFFR <0.88), middle (vFFR 0.88-0.93), and upper (vFFR ≥0.94). Vessels in the lower and middle tertile were more often LADs and had smaller stent diameters (p<0.001). Vessels in the lower and middle tertile had a higher risk of TVF as compared to vessels in the upper tertile (24.6% and 21.5% vs. 17.1%; adjusted HR 1.84 (95%CI 1.15-2.95), p = 0.011, and 1.58 (95%CI 1.02-2.45), p = 0.040) at 5-years follow-up. Additionally, vessels in the lower tertile had higher rates of TVR as compared to vessels in the higher tertile (12.6% vs. 6.5%, adjusted HR 1.93 (95%CI 1.06-3.53), p = 0.033)., Conclusion: Lower post-PCI vFFR values are associated with a significantly increased risk of TVF and TVR at 5-years follow-up., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Purpose of Review: Three-dimensional quantitative coronary angiography-based methods of fractional flow reserve (FFR) derivation have emerged as an appealing alternative to conventional pressure-wire-based physiological lesion assessment and have the potential to further extend the use of physiology in general. Here, we summarize the current evidence related to angiography-based FFR and perspectives on future developments., Recent Findings: Growing evidence suggests good diagnostic performance of angiography-based FFR measurements, both in chronic and acute coronary syndromes, as well as in specific lesion subsets, such as long and calcified lesions, left main coronary stenosis, and bifurcations. More recently, promising results on the superiority of angiography-based FFR as compared to angiography-guided PCI have been published. Currently available angiography -FFR indices proved to be an excellent alternative to invasive pressure wire-based FFR. Dedicated prospective outcome data comparing these indices to routine guideline recommended PCI including the use of FFR are eagerly awaited., (© 2022. The Author(s).)

Background: Intravascular ultrasound (IVUS) can overcome the intrinsic limitations of coronary angiography for lesion assessment and stenting. IVUS improves outcomes of patients presenting with stable or complex coronary artery disease, but dedicated data on the impact of IVUS-guided percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI) remains scarce., Methods: We systematically searched Embase, MEDLINE, Web of Science Core Collection, Cochrane Central Register of Controlled Trials and Google Scholar for studies that compared clinical outcomes for IVUS- versus angio-guided PCI in patients with AMI. The primary endpoint was all-cause mortality and the secondary endpoint major adverse cardiovascular events (MACE). Mantel-Haenszel random-effects model was used to calculate pooled risk ratios (RR) with 95% confidence intervals (CI)., Results: Nine studies (8 observational, 1 RCT) with a total of 838.902 patients (796.953 angio-guided PCI, 41.949 IVUS-guided PCI) were included. In patients with AMI, IVUS-guided PCI was associated with a significantly lower risk of all-cause mortality (pooled RR: 0.70; 95% CI, 0.59-0.82; p < 0.01), MACE (pooled RR: 0.86; 95% CI, 0.74-0.99; p = 0.04) and target vessel revascularization (TVR) (pooled RR: 0.83; 95% CI, 0.73-0.95; p < 0.01). In the subset of patients presenting with ST-segment elevation, IVUS-guided PCI remained associated with a reduced risk for both all-cause mortality (pooled RR: 0.79; 95% CI, 0.66-0.95, p = 0.01) and MACE (pooled RR: 0.86; 95% CI, 0.74-0.99, p = 0.04)., Conclusions: This is the first systematic review and meta-analysis comparing IVUS- versus angio-guided PCI in patients with AMI, showing a beneficial effect of IVUS-guided PCI on all-cause mortality, MACE and TVR. Results of ongoing dedicated prospective studies are needed to confirm these findings., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Coronary calcification has been linked to cardiovascular events. We developed and validated an algorithm to automatically quantify coronary calcifications on intravascular ultrasound (IVUS). We aimed to assess the prognostic value of an IVUS-calcium score (ICS) on patient-oriented composite endpoint (POCE)., Methods: We included patients that underwent coronary angiography plus pre-procedural IVUS imaging. The ICS was calculated per patient. The primary endpoint was a composite of all-cause mortality, stroke, myocardial infarction, and revascularization (POCE)., Results: In a cohort of 408 patients, median ICS was 85. Both an ICS ≥ 85 and a 100 unit increase in ICS increased the risk of POCE at 6-year follow-up (adjusted hazard ratio (aHR) 1.51, 95%CI 1.05-2.17, p value = 0.026, and aHR 1.21, 95%CI 1.04-1.41, p value = 0.014, respectively)., Conclusions: The ICS, calculated by a validated automated algorithm derived from routine IVUS pullbacks, was strongly associated with the long-term risk of POCE., (© 2021. The Author(s).)

Background: Patients with a low post PCI fractional flow reserve (FFR) are at increased risk for future adverse cardiac events. The aim of the present study was to assess the impact of specific intravascular ultrasound (IVUS) findings in patients with a low post percutaneous coronary intervention (PCI) FFR on long-term clinical outcome., Methods: In a subgroup analysis, 100 vessels with an FFR value ≤0.85 underwent post PCI IVUS to further assess the potential determinants for low post PCI FFR. No further action was taken to improve post PCI FFR. The primary endpoint of this study was the event free survival of target vessel failure (TVF) at two years in patients with a post PCI FFR ≤0.85, which was defined as a composite of cardiac death, target vessel myocardial infarction or target vessel revascularization., Results: In patients with a post PCI FFR ≤0.85, TVF free survival rates were 88.5% vs. 95.5% for patients with versus without residual proximal lesions and 88.2% vs. 95.5% for patients with versus without residual distal lesions respectively (HR = 2.53, 95% confidence interval (CI) 0.52-12.25, p = .25 and HR = 2.60, 95% CI 0.54-12.59, p = .24 respectively). TVF free survival was 92.8% vs. 93.5% in patients with versus without stent underexpansion >20% (HR = 1.01, 95% CI 0.21-4.88, p = .99) and 89.3% vs. 97.8% in patients with versus without any residual focal lesion including lumen compromising hematoma (HR = 4.64, 95% CI 0.55-39.22, p = .18)., Conclusion: Numerically higher TVF rates were observed in patients with a post PCI FFR ≤0.85 and clear focal residual disease as assessed with IVUS., Competing Interests: Declaration of Competing Interest LvZ received institutional research support from ACIST medical Inc. TN received institutional research support from ACIST medical Inc. JD reports to have received institutional research support from Pie Medical, ACIST Medical Inc., PulseCath, Medtronic, Boston Scientific, Abbott Vascular and speaker and consultancy fees from PulseCath, Medtronic, ReCor Medical, Acist Medical Inc. All other co-authors have no relevant conflict of interests to declare., (Copyright © 2020. Published by Elsevier B.V.)

Coronary calcification represents a challenge in the treatment of coronary artery disease by stent placement. It negatively affects stent expansion and has been related to future adverse cardiac events. Intravascular ultrasound (IVUS) is known for its high sensitivity in detecting coronary calcification. At present, automated quantification of calcium as detected by IVUS is not available. For this reason, we developed and validated an optimized framework for accurate automated detection and quantification of calcified plaque in coronary atherosclerosis as seen by IVUS. Calcified lesions were detected by training a supported vector classifier per IVUS A-line on manually annotated IVUS images, followed by post-processing using regional information. We applied our framework to 35 IVUS pullbacks from each of the three commonly used IVUS systems. Cross-validation accuracy for each system was >0.9, and the testing accuracy was 0.87, 0.89 and 0.89 for the three systems. Using the detection result, we propose an IVUS calcium score, based on the fraction of calcium-positive A-lines in a pullback segment, to quantify the extent of calcified plaque. The high accuracy of the proposed classifier suggests that it may provide a robust and accurate tool to assess the presence and amount of coronary calcification and, thus, may play a role in image-guided coronary interventions., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)