Culprit Lesions In Acute Coronary Syndromes Research Articles

The impact of SYNTAX score on culprit lesion morphology of acute coronary syndrome

Abstract Background The SYNTAX score quantifies the complexity of coronary artery morphology and is useful in determining the indication for CABG (Coronary Artery Bypass Grafting) or PCI (Percutaneous Coronary Intervention), which often reflect coronary artery disease severity. However, how SYNTAX score affects etiology of ACS (Acute Coronary Syndrome) patients observed by OCT (Optical Coherence Tomography) has been unclear. Methods This is a sub study of TACTICS OCT registry (n=702) which include ACS patients who underwent OCT guided PCI. Based on SYNTAX score, patients were divided into low-SYNTAX-group (1-22 points) and high-SYNTAX-group (23 points or higher). ACS culprit lesions were classified into plaque rupture (PR), plaque erosion (PE), and calcified nodule (CN). We compared patient characteristics and culprit lesions in low-group and high-group. Results High-SYNTAX-group was significantly younger with relatively greater prevalence of diabetes and lower body mass index. Peak CK, LVEF, Multi vessel and TIMI grade were also significantly greater in high-SYNTAX-group than low-SYNTAX-group. Although PR and PE were 2 most common etiologies of ACS in both groups, proportion of CN was much greater in high-SYNTAX-group than low-SYNTAX-group. Conclusion High-SYNTAX score was likely to have impact on ACS etiology increasing proportion of CN.

Poor prognosis of patients with acute coronary syndrome presenting optical coherence tomography-defined calcified nodule at culprit lesions after emergent percutaneous coronary intervention

Abstract Background Optical coherence tomography (OCT) enables the diagnosis of underlying causes of acute coronary syndrome (ACS). Calcified nodule (CN) is reported to be a rare but important cause of ACS, although its prognostic impact on clinical outcomes after emergent percutaneous coronary intervention (EPCI) remains undetermined. TACTICS registry is an investigator-initiated, prospective, multicenter, observational study to be conducted at 22 hospitals in Japan to clarify the prevalence of underlying causes of ACS defined by OCT (plaque rupture [PR], plaque erosion [PE] and CN) and its impact on clinical outcomes, and assess the feasibility of OCT-guided emergent PCI (UMIN-CTR, ID 000039050). Purpose This study aimed to clarify the prevalence of CN at the culprit lesions in ACS patients and its prognostication after EPCI in a large prospective registry. Methods We assessed 702 patients enrolled in TACTICS registry who underwent OCT assessment of the culprit lesion during EPCI. Advanced chronic kidney disease (CKD) was defined as those with creatinine clearance <30 ml/min/1.73m2. The prevalence of OCT-defined CN and occurrence of MACE, defined as a composite of cardiovascular death, myocardial infarction, heart failure, or ischemia-driven unplanned revascularization at 1 year were compared between patients with and without advanced CKD. Result Patients with advanced CKD was found in 5.4% of a total cohort. The prevalence of CN was 3.0% in patients with non-advanced CKD and 21.1% in those with advanced CKD (p<0.001). In advanced CKD, MACE occurred most frequently in patients with CN (87.5%), followed by plaque rupture (11.8%) and plaque erosion (10.0%) (p<0.001). In Cox hazard analysis, CN was a significant predictor for MACE in advanced CKD (hazard ratio [HR], 12.94 (3.31-50.67), p<0.001). In contrast, CN was not significant predictor for MACE in non-advanced CKD (HR1.931 (0.706-5.281), p=0.200). Conclusion CN is significantly more frequently found at the culprit lesions of ACS in advanced CKD patients. CN was associated with poor outcome in advanced CKD patients.

Predictors of Near-Infrared Spectroscopy-Detected Lipid-Rich Plaques by Optical Coherence Tomography-Defined Morphological Features in Patients With Acute Coronary Syndrome.

BackgroundNear-infrared spectroscopy (NIRS) provides the localization of lipid-rich components in coronary plaques. However, morphological features in NIRS-detected lipid-rich plaques (LRP) are unclear.MethodsA total of 140 de novo culprit lesions in 140 patients with the acute coronary syndrome (ACS) who underwent NIRS and optical coherence tomography (OCT) examinations for the culprit lesions at the time of percutaneous coronary interventions were investigated. We defined a NIRS-LRP as a lesion with a maximum lipid core burden index of 4 mm [LCBI4mm] > 500 in the culprit plaque. Clinical demographics, angiographic, and OCT findings were compared between the patients with NIRS-LRP (n = 54) vs. those without NIRS-LRP (n = 86). Uni- and multivariable logistic regression analyses were performed to examine the independent OCT morphological predictors for NIRS-LRP.ResultsClinical demographics showed no significant differences between the two groups. The angiographic minimum lumen diameter was smaller in the NIRS-LRP group than in the non- NIRS-LRP group. In OCT analysis, the minimum flow area was smaller; lipid angle, lipid length, the prevalence of thin-cap fibroatheroma, and cholesterol crystals were greater in the NIRS-LRP group than in the non-NIRS-LRP group. Plaque rupture and thrombi were more frequent in the NIRS-LRP group, albeit not significant. In a multivariable logistic regression analysis, presence of thin-cap fibroatheroma [odds ratio (OR): 2.56; 95% CI: 1.12 to 5.84; p = 0.03] and cholesterol crystals (OR: 2.90; 95% CI: 1.20 to 6.99; p = 0.02) were independently predictive of NIRS-LRP.ConclusionsIn ACS culprit lesions, OCT-detected thin-cap fibroatheroma and cholesterol crystals rather than plaque rupture and thrombi were closely associated with a great lipid-core burden.

Combined Use of Multiple Intravascular Imaging Techniques in Acute Coronary Syndrome.

Recent advances in intravascular imaging techniques have made it possible to assess the culprit lesions of acute coronary syndrome (ACS) in the clinical setting. Intravascular ultrasound (IVUS) is the most commonly used intravascular imaging technique that provides cross-sectional images of coronary arteries. IVUS can assess plaque burden and vessel remodeling. Optical coherence tomography (OCT) is a high-resolution (10 μm) intravascular imaging technique that uses near-infrared light. OCT can identify key features of atheroma, such as lipid core and thin fibrous cap. Near-infrared spectroscopy (NIRS) can detect lipid composition by analyzing the near-infrared absorption properties of coronary plaques. NIRS provides a chemogram of the coronary artery wall, which allows for specific quantification of lipid accumulation. These intravascular imaging techniques can depict histological features of plaque rupture, plaque erosion, and calcified nodule in ACS culprit lesions. However, no single imaging technique is perfect and each has its respective strengths and limitations. In this review, we summarize the implications of combined use of multiple intravascular imaging techniques to assess the pathology of ACS and guide lesion-specific treatment.

Abstract 10148: Prevalence, Clinical Characteristics and Cardiovascular Outcomes of Acute Coronary Syndrome Attributable to Coronary Subclavian Steal Syndrome in Patients with a History of Coronary Artery Bypass Grafting

Introduction: Coronary subclavian steal syndrome (CSSS) is coronary steal phenomenon due to subclavian artery stenosis (SAS) in patients with a history of CABG using internal mammary artery (IMA). While CSSS could cause acute coronary syndrome (ACS), its frequency, clinical characteristics and cardiovascular outcomes remain unknown. Methods: The current study was a retrospective multi-center analysis of 142 ACS patients who previously received CABG from January 2007 to October 2020. CSSS was defined as myocardial ischemia due to SAS. Clinical characteristics and cardiovascular events (=cardiac-cause death + myocardial infarction + stroke) were compared in subjects with and without CSSS. Results: CSSS was identified in 7.0% (=10/142) of study subjects. Of these, 1, 6 and 3 CSSS cases had SAS at right, left and both subclavian arteries, respectively. The averaged pressure gradient at SAS site was 31±13mmHg. ACS subjects attributable to CSSS were more likely to exhibit NSTEMI (90% vs. 52%, p=0.02), a history of hemodialysis (40% vs. 14%, p=0.03) and peripheral artery disease (70% vs. 20%, p<0.001). Of note, all of 4 CSSS subjects receiving hemodialysis had their arterial-venous fistula at the same side of SAS. With regard to revascularization procedure in CSSS subjects, primary endovascular treatment for SAS was performed in only 2 cases. Furthermore, despite SAS as a culprit lesion of ACS, primary PCI for native coronary lesion was conducted in other 6 cases. As a consequence, most of them (=5/6) required additional revascularization of SAS after primary PCI due to unresolved myocardial ischemia or chest pain. During 50-month observational period, CSSS was associated with a greater likelihood of cardiovascular (p=0.003) and stroke events (p<0.001, Figure). Conclusions: A substantially elevated cardiovascular risk was observed in ACS patients attributable to CSSS. This finding suggests clinical needs to meticulously evaluate SAS before and after CABG using IMA.

Abstract 12211: Water Hammer Shock Causing Rupture Of Vulnerable Cap Of Culprit Lesions In Acute Coronary Syndrome: An Angiographic And Machine Learning Analysis

Introduction: Acute coronary syndrome (ACS) is caused by rupture of coronary plaques. What triggers these ruptures? Hypothesis: In the field of hydraulics, in a setting of a tank and draining pipe, if the valve at the distal end of the pipe is open, the fluid flows normally. If the valve closes abruptly, the flow next to the valve stops. However the fluid from the tank continues to flow forward and can collide with the distal stationary fluid. This is called water hammer shock. Could the same event happen in coronary arteries? The contraction of the left ventricle (LV) is similar to the abrupt closure of a valve, stopping the myocardial capillary flow. Could the systolic LV contraction trigger water hammer shock? Methods: Angiograms with culprit lesions of ACS (recorded at 15 images/second or 0.06 second per image) were reviewed. The first image was of the artery completely filled with contrast. The subsequent images showed the blood in white color blood moving in over a background of black contrast. The normal flow was laminar. When there was retrograde on top of turbulent flow, this was evidence of a collision between antegrade and retrograde flow (or water hammer shock). The measurements by visual angiographic evaluation and by Machine Learning (ML) included (1) the duration and (2) size of coronary segment with turbulence. The ML program had 2 models (build on Python). Model 1 was built based on U-net and Densenet-121 for vessel segmentation. Model 2 was used for classification of flow. The model 2 was trained based on the convolutional neural network. Results: Angiograms of 20 ACS patients showed laminar flow (90%) in diastole. The flow became turbulent during systole with retrograde flow. The area of collision or water hammer shock showed diffuse coarse mixing of black (contrast) and white (blood). The presence of turbulence matched the location of 85% of ruptured plaques. The duration of turbulence lasted 80% of systole. Special protocols were used successfully to train AI to recognize the lesions, retrograde and turbulent flow. Conclusions: With the new angiographic technique, detailed images of water hammer shock matched the location of ruptured plaques in ACS patients. These results may help to understand the genesis and offer precise prevention and treatment for ACS

Coronary lipid-rich plaque characteristics with acute coronary syndrome and chronic coronary syndrome: a near infrared spectroscopy and intravascular ultrasound study

Abstract Background Asians have a much lower incidence of adverse coronary events than Caucasians, and the characteristics of vulnerable plaque might be different among the ethnics. Purpose The aim of this study was to investigate the clinical characteristics of lipid-rich plaque (LRP) in the Asian population and we also aimed to distinguish the characteristics of an acute coronary syndrome (ACS) culprit lesion and a chronic coronary syndrome (CCS) culprit lesion. Furthermore, we evaluated the association between lipid core burden index (LCBI) and cardiovascular risk factors, lipid profiles, and inflammatory biomarkers, as determined in vivo by near infrared spectroscopy intravascular ultrasound (NIRS-IVUS) imaging in patients undergoing percutaneous coronary intervention (PCI). Methods We evaluated 207 patients (ACS, n=75; CCS, n=132) who underwent PCI under NIRS-IVUS. Plaque characteristics and the extent of LRP [defined as a long segment with a 4-mm maximum LCBI (maxLCBI4mm)] on NIRS in de-novo culprit and non-culprit segments were analyzed. Results The mean age was 65 years old and 82% of patients were male. The ACS culprit lesions had a significantly higher maxLCBI4mm (median [interquartile range (IQR)]: 533 [385–745] vs. 361 [174–527], p<0.001) than the CCS culprit lesions. Whereas, no significant difference was seen in maxLCBI4mm between ACS and CCS non-culprit lesion segments (246 [53, 342] vs. 185 [37, 350], p=0.47) (Figure 1). Receiver-operating characteristic analysis showed that the NIRS maxLCBI4mm could distinguish the ACS culprit segment from the CCS culprit segment, with a sensitivity of 73% and a specificity of 69% (c-statistic = 0.69; p<0.001, cut-off value of max LCBI4mm = 408) (Figure 2). On multivariate logistic analysis, a large LRP (defined as maxLCBI4mm ≥400) was the strongest independent predictor of the ACS culprit segment (odds ratio, 3.87; 95% confidence interval, 1.95–8.02). In non-culprit segments, 19.8% of patients had at least one large LRP without a small lumen. No significant correlation was found between the extent of LRP and circulating lipid profiles and inflammatory makers biomarkers (hs-CRP, IL-6, TNF-α) in both the culprit and non-culprit lesion segments, whereas the extent of LRP was positively correlated with IVUS plaque burden (r=0.24, p<0.001). Conclusions We confirmed that NIRS-IVUS plaque assessment could be useful to differentiate ACS from CCS culprit lesions, and that a threshold maxLCBI4mm ≥400 was clinically suitable in Japanese patients. No systemic surrogate markers were found to be associated with the extent of LRP by NIRS in culprit and non-culprit segments. Consequently, we believe that direct intravascular evaluation of coronary plaque characteristics remains important for identification of high-risk LRP. Funding Acknowledgement Type of funding sources: None. Figure 1. The difference of maxLCBI4mmFigure 2. ROC curve

Plaque Character and Progression According to the Location of Coronary Atherosclerotic Plaque

Although acute coronary syndrome culprit lesions occur more frequently in the proximal coronary artery, whether the proximal clustering of high-risk plaque is reflected in earlier-stage atherosclerosis remains unclarified. We evaluated the longitudinal distribution of stable atherosclerotic lesions on coronary computed tomography angiography (CCTA) in 1,478 patients (mean age, 61 years; men, 58%) enrolled from a prospective multinational registry of consecutive patients undergoing serial CCTA. Of 3,202 coronary artery lesions identified, 2,140 left lesions were classified (based on the minimal lumen diameter location) into left main (LM, n=128), proximal (n=739), and other (n=1,273), and 1,062 right lesions were classified into proximal (n=355) and other (n=707). Plaque volume (PV) was the highest in proximal lesions (median, 26.1 mm3), followed by LM (20.6 mm3) and other lesions (15.0 mm3, p <0.001), for left lesions, and was lager in proximal (25.8 mm3) than in other lesions (15.2 mm3, p <0.001) for right lesions. On both sides, proximally located lesions tended to have greater necrotic core and fibrofatty components than other lesions (left: LM, 10.6%; proximal, 5.8%; other, 3.4% of the total PV, p <0.001; right: proximal, 8.4%; other 3.1%, p <0.001), with less calcified plaque component (left: LM, 18.3%; proximal, 30.3%; other, 37.7%, p <0.001; right: proximal, 23.3%, other, 36.6%, p <0.001), and tended to progress rapidly (adjusted odds ratios: left: LM, reference; proximal, 0.95, p=0.803; other, 0.64, p=0.017; right: proximal, reference; other, 0.52, p <0.001). Proximally located plaques were larger, with more risky composition, and progressed more rapidly.

Morphological Plaque Characteristics and Clinical Outcomes in Patients With Acute Coronary Syndrome and a Cancer History

BackgroundAlthough patients with a cancer history have a 2 to 3 times higher risk for acute coronary syndrome (ACS), the morphological characteristics of ACS culprit plaque in those patients and their relations with clinical outcomes remain unknown.Methods and ResultsThis retrospective, multicenter, observational cohort study included consecutive patients with ACS who underwent optical coherence tomography‐guided emergent percutaneous coronary intervention. Patients were categorized into those without a cancer history, those with a cancer history, and those currently receiving cancer treatment. ACS culprit lesions were classified as plaque rupture, plaque erosion, or calcified nodule using optical coherence tomography. Plaque erosion frequency was significantly higher in culprit lesions of patients with current cancer and patients with cancer history than in those of patients without cancer history (56.3% versus 61.7% versus 36.5%). Calcified nodule incidence was significantly higher in patients without cancer history than in patients with current cancer and patients without cancer history (patients with current cancer: 12.4% versus patients without cancer history: 25.5% versus patients without cancer history: 12.6%, P<0.001). Cancer history was independently associated with nonplaque rupture (plaque erosion or calcified nodule) in ACS culprit lesions (odds ratio, 4.00; P<0.001). Cancer history was independently associated with major adverse cardiovascular events (hazard ratio [HR], 1.98; P=0.002). Nonplaque rupture in ACS culprit lesions was independently associated with major adverse cardiovascular events (HR, 1.60; P=0.011).ConclusionsPatients with a cancer history had significantly worse clinical outcomes after ACS than those without a cancer history. Those with a cancer history had significantly higher plaque erosion and calcified nodule incidences in the ACS culprit lesions, which might partly explain their worse clinical outcomes.RegistrationURL: www.umin.ac.jp/ctr/index.htm. Unique Identifier: UMIN000038442.

Relationship among clinical characteristics, morphological culprit plaque features, and long-term prognosis in patients with acute coronary syndrome.

Culprit lesions of acute coronary syndrome (ACS) could be classified as plaque rupture (PR), erosion, or calcified nodule (CN). We aimed to determine the relationship among clinical characteristics, morphological plaque features, and long-term prognosis in ACS. Patients with ACS, who underwent pre-intervention optical coherence tomography between April 2013 and July 2018 were retrospectively enrolled, and classified into the three groups based on the culprit lesion morphology. In the 436 patients enrolled, incidences of PR, erosion, and CN in ACS culprit lesions were 46.1, 39.9, and 14.0%, respectively. Plaque erosion was more frequent in men aged < 60 years and CN was more frequent in older adults in both sexes (≥ 80 years) (P < 0.001). Patients with CN had a higher incidence of hemodialysis treatment (P < 0.001) and diabetes (P = 0.003). Multivariate analysis revealed that ST elevation myocardial infarction (STEMI) (P = 0.049) and presence of thin-cap fibroatheroma (TCFA) at the culprit lesion were independently associated with PR; in younger patients (< 60 year), preserved left ventricular ejection fraction and lower incidence of TCFA were correlated with plaque erosion; and older age, non-STEMI, or unstable angina pectoris, higher serum brain natriuretic peptide levels, and lower incidence of TCFA were independently associated with CN. Multivariable analysis revealed that CN (odds ratio [OR] 1.990, P = 0.005), male sex (OR 2.012, P = 0.004), and older age (OR 1.036, P < 0.001) were independently associated with future adverse events during a median follow-up of 757 days. Different patient characteristics and morphological features were associated with the type of culprit lesion in patients with ACS.

Coronary lipid-rich plaque characteristics in Japanese patients with acute coronary syndrome and stable angina: A near infrared spectroscopy and intravascular ultrasound study.

Asians have a much lower incidence of adverse coronary events than Caucasians. We sought to evaluate the characteristics of coronary lipid-rich plaques (LRP) in Asian patients with acute coronary syndrome (ACS) and stable angina (SA). We also aimed to identify surrogate markers for the extent of LRP. We evaluated 207 patients (ACS, n=75; SA, n=132) who underwent percutaneous coronary intervention under near infrared spectroscopy intravascular ultrasound (NIRS-IVUS). Plaque characteristics and the extent of LRP [defined as a long segment with a 4-mm maximum lipid-core burden index (maxLCBI4mm)] on NIRS in de-novo culprit and non-culprit segments were analyzed. The ACS culprit lesions had a significantly higher maxLCBI4mm (median [interquartile range (IQR)]: 533 [385-745] vs. 361 [174-527], p<0.001) than the SA culprit lesions. On multivariate logistic analysis, a large LRP (defined as maxLCBI4mm≥400) was the strongest independent predictor of the ACS culprit segment (odds ratio, 3.87; 95% confidence interval, 1.95-8.02). In non-culprit segments, 19.8% of patients had at least one large LRP without a small lumen. No significant correlation was found between the extent of LRP and systematic biomarkers (hs-CRP, IL-6, TNF-α), whereas the extent of LRP was positively correlated with IVUS plaque burden (r=0.24, p<0.001). We confirmed that NIRS-IVUS plaque assessment could be useful to differentiate ACS from SA culprit lesions, and that a threshold maxLCBI4mm≥400 was clinically suitable in Japanese patients. No surrogate maker for a high-risk LRP was found; consequently, direct intravascular evaluation of plaque characteristics remains important.

Morphological plaque characteristics and clinical outcomes of acute coronary syndrome patients with a cancer history

Abstract Background Although previous studies have reported that patients with a history of cancer have 2–3 times higher risks for acute coronary syndrome (ACS), morphological culprit plaque characteristics in ACS patients with a cancer history and their relations with clinical outcomes remain unknown. Methods The Kobe University ACS-OCT registry is a multi-center registry of consecutive ACS patients who underwent OCT-guided emergent PCI in Japanese four centers. All patients were categorized into the patients without a history of cancer (non-cancer), those with a history of cancer who diagnosed more than one year before ACS (historical), and those with ongoing cancer treatment or diagnosis within one year before ACS (current). ACS culprit lesions were classified into plaque rupture (PR), plaque erosion (PE), and calcified nodule (CN) according to morphological features by OCT and clinical events were collected after the onset of ACS. Results Among 436 patients, 63 patients (14.4%) had a history of cancer or ongoing treatment of cancer (cancer patients). Cancer patients were significantly older than non-cancer patients (73.4±9.4 vs. 66.9±12.9, p=0.001), and non-ST segment elevation ACS was more frequently observed in cancer patients than in non-cancer patients (57.1% vs. 43.2%, p=0.039). Regarding the ACS culprit lesion, the frequency of PR was significantly lower and the frequencies of PE and CN were significantly higher in the cancer patients than in the non-cancer patients (Figure A1). The cumulative incidence of major adverse cardiovascular event (MACE: composite of cardiac death, non-fatal myocardial infarction, and any revascularization, stroke, and heart failure with admission) after the onset of ACS in cancer patients was significantly higher than that in the non-cancer patients (Figure B1). When the cancer patients were categorized into the historical and the current cancer patients, the frequency of PE was higher in the current and the historical cancer patients than the non-cancer patients. Also, the incidence of CN was significantly higher in the historical cancer patients than others (Figure A2). The cumulative incidence of MACE was significantly higher in the current cancer patients, followed by historical and non-cancer patients (Figure B2). Cox regression analyses demonstrated that the non-PR lesion (hazard ratio (HR) 0.65, 0.46–0.94, p=0.021), patients with multivessel disease (HR 2.55, 1.79–3.64, p&amp;lt;0.001), older patients (HR 1.02, 1.00–1.03, p=0.043) were independently associated with MACE after ACS. Moreover, multivariate analysis demonstrated that cancer history (HR 4.64, 2.34–9.21, p&amp;lt;0.001) and non-ST segment elevation ACS (HR 0.66, 2.34–9.21, p=0.038) were independently associated with non-PR lesion. Conclusions The present study revealed the difference in morphological plaque characteristics between cancer and non-cancer patients, which might explain potential underlying mechanisms for worse outcomes in cancer patients. Funding Acknowledgement Type of funding source: None

Intracoronary polarimetry for characterizing coronary plaque vulnerability in patients with coronary artery disease

Abstract Background Intracoronary polarimetry with polarization-sensitive (PS-) optical frequency domain imaging (OFDI) measures polarization properties, including birefringence and depolarization, in parallel with structural features of conventional OFDI (Figure 1A). Collagen, which imparts mechanical integrity to fibrous caps, and collagen-synthesizing smooth muscle cells exhibit elevated birefringence. Depolarization is increased by the presence of macrophages and lipid/necrotic cores. Purpose This study aimed to compare conventional OFDI and polarimetric signatures of coronary lesions between patients with acute coronary syndrome (ACS) and chronic coronary syndrome (CCS). Furthermore, we aimed to determine a birefringence cut-off value for identifying which fibrous caps belong to ACS culprit lesions. Methods This study consisted of 37 patients with ACS (n=23) or CCS (n=14). ACS culprit lesions (ACS-lesions) and CCS stenotic lesions (CCS-lesions) were included in the analysis (820 mm). Qualitative and quantitative conventional OFDI analysis included the presence of plaque rupture, macrophage infiltration, micro-vessels, thrombus, stenosis severity, fibrous cap thickness (FCT), lipid arc, lipid-burden and calcium-burden index. Birefringence and depolarization of the coronary lesions and fibrous caps were measured in the cross-sectional images showing the minimum FCT or minimum luminal area. Predictors of ACS-lesions were investigated by multivariate regression analysis. Receiver operating characteristic (ROC) analysis was used to determine the birefringence cut-off value identifying ACS fibrous caps (ACS-caps). Results There were no significant differences in clinical characteristics between the two groups, except for previous history of coronary artery disease. Compared to CCS-lesions, ACS-lesions featured higher lipid-burden index and maximum lipid arc (both p&amp;lt;0.05). ACS-lesions featured lower birefringence and higher depolarization than CCS-lesions (p&amp;lt;0.05). Multivariable regression demonstrated an independent association of birefringence with ACS-lesions (p&amp;lt;0.05), even after adjusting for the conventional OFDI findings. Limiting the analysis to the fibrous caps, ACS-caps exhibited significantly lower birefringence (p&amp;lt;0.05) and higher depolarization (p&amp;lt;0.05) that CCS-caps. ROC analysis for differentiating ACS-caps from CCS-caps found that a birefringence value of 0.0004 results in a sensitivity and specificity of 88% and 82%, respectively (Figure 1B, AUC = 0.82). Conclusions Intracoronary polarimetry provides quantitative assessment of coronary lesions related to their composition. Birefringence was an independent robust predictor of ACS-lesions. Decreased birefringence and pronounced depolarization within the ACS-caps may indicate increased collagenolytic activity and macrophage infiltration, respectively. These results suggest that polarization properties may serve as quantitative imaging markers for assessing plaque vulnerability. Figure 1 Funding Acknowledgement Type of funding source: Other. Main funding source(s): This work was supported by the National Institutes of Health and by Terumo Corporation.

TCT-9 Quantitative Assessment of Lipid Composition by NIRS-IVUS Is Helpful for Differentiating Among Plaque Rupture, Plaque Erosion, and Calcified Nodule in the Culprit Lesion of ACS

In vivo precise differentiation among plaque rupture (PR), plaque erosion (PE), and calcified nodule (CN) in the culprit lesion of acute coronary syndrome (ACS) is a major challenge for intravascular imaging. We performed both optical coherence tomography (OCT) and near-infrared spectroscopy

TCTAP A-081 Quantitative Assessment of Vulnerable Plaque by NIRS-IVUS Is Helpful for Differentiating Among Plaque Rupture, Plaque Erosion and Calcified Nodule in the Culprit Lesion of ACS.

In vivo, precise differentiation among plaque rupture (PR), plaque erosion (PE) and calcified nodule (CN) in the culprit lesion of an acute coronary syndrome (ACS) is a major challenge for intravascular imaging. We perfumed both optical coherence tomography (OCT) and near-infrared spectroscopy

In vivo vulnerability grading system of plaques causing acute coronary syndromes: An intravascular imaging study

BackgroundAutopsy studies shed light on the interplay between fatal acute coronary syndromes (ACS) and features of plaque vulnerability. This is a prospective pilot study designed for generating a new in vivo imaging grading system of plaque vulnerability. MethodsWe studied 87 coronary vessels in 63 consecutive patients: 48 with Acute Coronary Syndrome (ACS) and 15 with stable coronary artery disease using IntraVascular-Ultrasound Near-Infrared-Spectroscopy (IVUS-NIRS) and Optical Coherence Tomography (OCT). We identified 99 lesions: 21 were the ACS culprit lesions (18 ulcerations and 3 with intact fibrous cap), 78 were non-culprit lesions including plaques located in the same ACS culprit vessel (N12), plaques located in a non-culprit vessel in patients with ACS (28) and target lesions of stable patients (N 38). A second analysis focused on lipid plaques, comparing the 18 ACS culprit ulcerated lesions and the 55 non-culprit lesions. ResultsThe co-presence of the following three features of vulnerability [Minimal Luminal Area (MLA) <4 mm2, Fibrous Cap Thickness (FCT) < 75 μm and superficial macrophages] was by far more frequent in ACS culprit lesions than in controls (OR 40.6 for all lesions and OR 45.7 for ulcerated culprit lesions only). The triple-feature OCT grading identified vulnerable plaques with a much higher accuracy than that obtained applying each single feature of vulnerability. ConclusionsThe co-presence of the 3 OCT features of vulnerability (MLA < 4 mm2, FCT < 75 μm and superficial macrophages) identifies culprit ACS lesions with a very high odd ratio. This finding could set the basis for a new OCT vulnerability grading system including superficial macrophages.

Differences in the association of total versus local coronary artery calcium with acute coronary syndrome and culprit lesions in patients with acute chest pain: The coronary calcium paradox

Background and aimsTotal coronary artery calcium (CAC) burden is associated with an increased cardiovascular risk, while local CAC may represent stable plaques. We determined differences in relationship of total CAC with acute coronary syndrome (ACS) and local CAC with culprit lesions in patients with suspected ACS. MethodsWe performed computed tomography (CT) for CAC and CT angiography to assess the presence of significant stenosis and high-risk plaque (positive remodeling, low CT attenuation, napkin-ring sign, spotty calcium) in 37 patients with ACS and 223 controls. Total and segmental Agatston scores were measured. Culprit lesions were assessed in subjects with ACS. ResultsPatients (n = 260) with vs. without ACS had higher total CAC score (median 229, 25th-75th percentile 75–517 vs. 27, 25th-75th percentile 0–99, p<0.001), higher prevalence of significant stenosis (78% vs. 7%, p<0.001) and high-risk plaque (95% vs. 59%, p<0.001). In those with ACS, culprit (n = 41) vs. non-culprit (n = 200) lesions, had similar segmental CAC score (median 22, 25th-75th percentile 4–71 vs. 14, 25th-75th percentile 0–51; p=0.37), but higher prevalence of significant stenosis (81% vs. 11%, p<0.001) and high-risk plaque (76% vs. 51%, p=0.005). Significant stenosis (odds ratio 40.2, 95%CI 15.6–103.9, p<0.001) and high-risk plaque (odds ratio 3.4, 95%CI 1.3–9.1, p=0.02), but not segmental CAC score (odds ratio 1.0, 95%CI 1.0–1.0, p=0.47), were associated with culprit lesions of ACS. ConclusionsTotal CAC burden was associated with ACS but segmental CAC was not associated with culprit lesions. Our findings suggest that total but not local CAC is a marker of ACS risk and support the hypothesis that extensive local CAC is a marker of plaque stability.

Association between cholesterol crystals and culprit lesion vulnerability in patients with acute coronary syndrome: An optical coherence tomography study

BackgroundCholesterol Crystals (ChCs) are recognized as a hallmark of advanced atherosclerotic lesions. Previous animal and histopathology studies have revealed that Cholesterol crystallization trigger a local inflammatory response and plaque rupture. We sought to investigate the in vivo relationship between ChCs and culprit lesion vulnerability in patients with acute coronary syndrome (ACS). Methods206 culprit lesions from 206 patients with ACS who underwent optical coherence tomography (OCT) imaging were divided into 2 groups based on the presence or absence of ChCs. Culprit lesions characteristics were compared between ChCs and Non-ChCs groups. ResultsFor overall ACS patients, culprit lesions with ChCs had higher incidence of macrophages accumulation (77.8% vs. 40.0%, p < 0.001), microchannel (67.9% vs. 24.8%, p < 0.001), plaque rupture (58.0% vs. 36.0%, p = 0.001), thrombosis (66.7% vs. 49.6%, p = 0.016) and spotty calcification (35.8% vs. 10.4%, p < 0.001). In addition, the mean lipid arc (274.2 ± 57.6° vs. 228.1 ± 66.3°, p < 0.001) was larger and the lipid index (3826.1 ± 2111.4 vs. 2855.0 ± 1753.0, p = 0.001) was greater. The frequency of ChCs was significantly higher in patients with STEMI, as compared with NSTEACS (50.8% vs. 34.7%, p = 0.032). Larger lipid arc, higher incidence of macrophages accumulation and that of microchannel were observed in culprit lesions with ChCs in both STEMI (p = 0.028, p < 0.001, and p = 0.002 respectively) and NSTEACS (p < 0.001, p < 0.001, and p < 0.001 respectively) subgroups. ConclusionChCs were frequently associated with characteristics of vulnerable plaques in ACS culprit lesions as well as in STEMI and NSTEACS subgroups. ChCs and vulnerable plaque features were more often observed in culprit lesions of STEMI patients compared to NSTEACS patients.

Characteristics of high-risk coronary plaques identified by computed tomographic angiography and associated prognosis: a systematic review and meta-analysis.

To clarify the potential role of coronary computed tomographic angiography (CCTA) in characterizing and prognosticating high-risk coronary plaques. A systematic review and meta-analysis were conducted to compare high-risk vs. low-risk plaques and culprit vs. non-culprit lesions in patients with acute coronary syndrome (ACS) vs. stable angina (SA). High-risk plaques were defined by at least one of the following features: non-calcified plaque (NCP), the presence of spotty calcified plaque (SCP), or increased remodelling index (RI). Results of included studies were pooled as odds ratios (OR) or weighted mean differences (WMD) with 95% confidence interval (CI). Eighteen eligible studies provided data to compare plaque types, plaque volume, and RI. Six studies provided data on ACS events in vulnerable high-risk vs. low-risk calcified plaques after 35 ± 2 months of follow-up. ACS patients had significantly higher number of NCP and SCP compared with SA patients with OR = 1.96 (1.47-2.60; 95% CI) P = 0.0001 and OR = 4.5 (2.98-6.83; 95% CI) P = 0.0001, respectively. Total plaque volume in ACS was not larger than SA: WMD = 22.9 (-22.1 to 67; 95% CI) mm(3), P = 0.32, but NCP volume was significantly larger: WMD = 28.8 (10.9-46.7; 95% CI) mm(3), P = 0.002. RI was higher in culprit lesions in ACS compared with SA and compared with non-culprit lesions in ACS patients: WMD = 0.48 (0.25-0.70; 95% CI) P = 0.0001 and 0.19 (0.07-0.30) P = 0.0001, respectively. The associated risk of future ACS was significantly higher in high-risk than in low-risk plaques: OR = 12.1 (5.24-28.1; 95% CI) P = 0.0001. CCTA can non-invasively characterize high-risk vulnerable coronary plaques and can predict future ACS events in patients with high-risk plaques.

Age- and sex-related differences in coronary plaque high-risk features in patients with acute coronary syndrome assessed by computed tomography angiography

Age- and sex-related differences in the pathological features of acute coronary syndrome (ACS) culprit lesions (CLs) have been reported [1,2]. Coronary computed tomography angiography (CCTA) has the potential to detect high-risk coronary plaques by characterizing non-calcified coronary atherosclerotic plaques (NCPs), including pure non-calcified plaques and non-calcified plaques associated with coronary calcium [3–6]. In this study, we investigated whether CCTA differentiated age- and sex-specific characteristics of ACS CLs by analyzing NCPs.