Association of Coronary Computed Tomography-Defined Myocardial Bridge With Pre- and Post-Procedural Fractional Flow Reserve in Patients Undergoing Elective Percutaneous Coronary Intervention.

BACKGROUND: Myocardial bridge (MB) is a common coronary anomaly characterized by a tunneled course through the myocardium. Coronary computed tomography angiography (CCTA) can identify MB. The impact of MB detected by CCTA on coronary physiological parameters before and after percutaneous coronary intervention (PCI) is unknown.Methods and Results: We investigated 141 consecutive patients who underwent pre-PCI CCTA and fractional flow reserve (FFR)-guided elective PCI for de novo single proximal lesions in the left anterior descending artery (LAD). We compared clinical demographics and physiological parameters between patients with and without CCTA-defined MB. MB was identified in 46 (32.6%) patients using pre-PCI CCTA. The prevalence of diabetes was higher among patients with MB. Median post-PCI FFR values were significantly lower among patients with than without MB (0.82 [interquartile range 0.79-0.85] vs. 0.85 [interquartile range 0.82-0.89]; P=0.003), whereas pre-PCI FFR values were similar between the 2 groups. Multivariable linear regression analysis revealed that the presence of MB and greater left ventricular mass volume in the LAD territory were independently associated with lower post-PCI FFR values. Multivariable logistic regression analysis also revealed that the presence of MB and lower pre-PCI FFR values were independent predictors of post-PCI FFR values ≤0.80. CONCLUSIONS: CCTA-defined MB independently predicted both lower post-PCI FFR as a continuous variable and ischemic FFR as a categorical variable in patients undergoing elective PCI for LAD.

Noninvasive transthoracic doppler flow velocity and invasive thermodilution to assess coronary flow reserve.

Background: Coronary flow reserve (CFR) provides prognostication and coronary physiological information, including epicardial coronary stenosis and microvascular function. The relationship between stress transthoracic Doppler echocardiography (TDE)-derived coronary flow velocity reserve (CFRS-TDE) and thermodilution-derived coronary flow reserve (CFRthermo) before and after elective percutaneous coronary intervention (PCI) remains unclear. Methods: This single-center prospective registry study evaluated patients who underwent fractional flow reserve (FFR)-guided elective PCI for left anterior descending artery (LAD) lesions with wire-based invasive physiological measurements and pre- and post-PCI stress TDE examinations. Results: A total of 174 LAD lesions from 174 patients were included in the final analysis. A modest correlation was detected between the pre-PCI CFRS-TDE and the pre-PCI CFRthermo (r=0.383, P<0.001). The frequently used CFRS-TDE threshold of 2.0 corresponded to a pre-PCI CFRthermo of 2.18. Pre-PCI CFRS-TDE underestimated pre-PCI CFRthermo [1.89 (1.44-2.31) vs. 2.05 (1.38-2.93), P<0.001]. Both CFRS-TDE and CFRthermo increased significantly post-PCI [pre-PCI CFRS-TDE 1.89 vs. post-PCI CFRS-TDE 2.33, P<0.001; pre-PCI CFRthermo 2.05 (1.38-2.93) vs. post-PCI CFRthermo 2.59 (1.63-3.55), P<0.001]. In contrast, there was no significant relationship between changes in CFRS-TDE and changes in CFRthermo after PCI (r=0.008, P=0.915) or between post-PCI CFRS-TDE and post-PCI CFRthermo (r=0.054, P=0.482). Conclusions: Pre-PCI CFRS-TDE and CFRthermo are modestly correlated, but post-PCI CFRS-TDE and CFRthermo have no correlation. CFRS-TDE and CFRthermo are not interchangeable, particularly post-PCI, suggesting that the two metrics represent different coronary physiologies after PCI.

Higher Noncalcified Plaque Volume Is Associated With Increased Plaque Vulnerability and Vascular Inflammation.

BACKGROUND: Recently, it was reported that noncalcified plaque (NCP) volume was an independent predictor for cardiac events. Pericoronary adipose tissue (PCAT) attenuation is a marker of vascular inflammation and has been associated with increased cardiac mortality. The aim of this study was to evaluate the relationships between NCP volume, plaque vulnerability, and PCAT attenuation. METHODS: Patients who underwent preintervention coronary computed tomography angiography and optical coherence tomography were enrolled. Plaque volume was measured by computed tomography angiography, plaque vulnerability by optical coherence tomography, and the level of coronary inflammation by PCAT attenuation. The plaques were divided into 2 groups of high or low NCP volume based on the median NCP volume. RESULTS: Among 704 plaques in 454 patients, the group with high NCP volume had a higher prevalence of lipid-rich plaque (87.2% versus 75.9%; P<0.001), thin-cap fibroatheroma (38.1% versus 20.7%; P<0.001), macrophage (77.8% versus 63.4%; P<0.001), microvessel (58.2% versus 42.9%; P<0.001), and cholesterol crystal (42.0% versus 26.7%; P<0.001) than the group with low NCP plaque volume. The group with high NCP volume also had higher PCAT attenuation than the group with low NCP volume (-69.6±10.0 versus -73.5±10.6 Hounsfield unit; P<0.001). In multivariable analysis, NCP volume was significantly associated with thin-cap fibroatheroma and high PCAT attenuation. In the analysis of the combination of PCAT attenuation and NCP volume, the prevalence of thin-cap fibroatheroma was the highest in the high PCAT attenuation and high NCP volume group and the lowest in the low PCAT attenuation and low NCP volume group. CONCLUSIONS: Higher NCP volume was associated with higher plaque vulnerability and vascular inflammation. The combination of PCAT attenuation and NCP volume may help identify plaque vulnerability noninvasively. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04523194.

Detection of unrecognized myocardial infarction by preprocedural transthoracic echocardiography in patients undergoing elective percutaneous coronary intervention.

BACKGROUND: Previous studies showed that unrecognized myocardial infarction (UMI) identified on cardiac magnetic resonance (CMR) was related to worse prognosis. We aimed to investigate the efficacy of preprocedural transthoracic echocardiography (TTE) to detect the presence of UMI in patients undergoing percutaneous coronary intervention (PCI). METHODS: A total of 138 patients with chronic coronary syndrome (CCS) and preserved left ventricular ejection fraction (LVEF) without history of myocardial infarction or revascularization were retrospectively studied. UMI was evaluated with pre-PCI late gadolinium enhancement (LGE)-CMR. TTE and two-dimensional speckle-tracking echocardiography (2D-STE) were performed before PCI. All patients were divided into two groups according to the presence or absence of UMI, and clinical and echocardiographic findings were compared between these two groups. RESULTS: UMI was detected in 43 patients (31.2%). Multivariable logistic regression analysis revealed that higher SYNTAX score, the presence of wall motion abnormalities (WMAs) and lower global longitudinal strain (GLS) were independent predictors of the presence of UMI. Furthermore, GLS provided incremental efficacy for the detection of UMI over abnormal Q waves, SYNTAX score and WMAs. CONCLUSIONS: Preprocedural TTE in combination with 2D-STE could help identify patients with UMI regardless of the presence or absence of ECG findings and WMAs.

Combined Assessment of Fractional Flow Reserve and Coronary Flow Velocity Reserve after Drug-Eluting Stent Implantation.

BACKGROUND: Coronary flow velocity reserve (CFVR) can be measured noninvasively using stress transthoracic Doppler echocardiography (S-TDE). The prognostic significance of S-TDE-derived CFVR after percutaneous coronary intervention (PCI) remains unknown. The aim of this study was to investigate the prognostic value of post-PCI CFVR and its additional efficacy to fractional flow reserve (FFR) in patients undergoing elective PCI. METHODS: A retrospective study was conducted involving 187 consecutive patients with chronic coronary syndrome who underwent elective PCI guided by FFR for the left anterior descending coronary artery. Pre- and post-PCI wire-based FFR and CFVR assessments of the left anterior descending coronary artery using S-TDE were performed in all patients. The association between post-PCI clinical and physiologic parameters and major adverse cardiac events (MACE), defined as a composite of cardiac death, myocardial infarction, heart failure, and unplanned remote target vessel revascularization, was evaluated. RESULTS: Three-quarters of patients exhibited CFVR increase after PCI, while all patients showed FFR improvement. During a median follow-up period of 1.5 years, MACE occurred in 21 patients (11.2%). Among clinical demographics, patients with MACE had higher levels of N-terminal pro-brain natriuretic peptide compared with those without MACE (median, 615 pg/mL [interquartile range, 245-1,500 pg/mL] vs 180 pg/mL [interquartile range, 70-559 pg/mL]; P = .010). Post-PCI S-TDE-derived CFVR was lower in patients with MACE, while post-PCI FFR showed a nonsignificant tendency to be lower in patients with MACE. In a multivariable analysis, higher NT-proBNP (adjusted hazard ratio, 1.33; 95% CI, 1.02-1.74; P = .038), post-PCI CFVR ≤ 2.0 (adjusted hazard ratio, 2.93; 95% CI, 1.16-7.40; P = .023), and post-PCI FFR ≤ 0.82 (adjusted hazard ratio, 3.93; 95% CI, 1.52-10.18; P = .005) were independently associated with MACE. CONCLUSIONS: In patients with chronic coronary syndrome who underwent successful elective PCI for left anterior descending coronary artery, the combined assessment of S-TDE-derived post-PCI CFVR and post-PCI FFR provided a significant association with the occurrence of MACE.

Diagnostic value of computed tomography myocardial perfusion imaging to detect coexisting microvascular dysfunction in patients with obstructive epicardial coronary artery disease.

Background: Computed tomography myocardial perfusion (CT-MP) has reported usefulness in assessing hemodynamically significant epicardial coronary artery lesions. However, the diagnostic ability of the absolute coronary flow using CT-MP to detect coronary microvascular dysfunction (CMD) remains elusive. This prospective cohort study aimed to assess the diagnostic value of CT-MP in evaluating coexisting CMD in patients with functionally significant epicardial coronary stenosis and to analyze the predictive factors of lesions with CMD. Methods: Sixty-eight patients with chronic coronary syndrome (CCS) and de novo single functionally significant stenosis [fractional flow reserve (FFR) ≤0.80] were studied. CMD was defined as an index of microcirculatory resistance ≥25. We compare clinical background and CT-MP findings between patients with and without CMD (CMD, n=29; non-CMD, n=39). CT-MP, and quantitative and qualitative plaque assessments were included in computed tomography angiography assessment. Logistic regression analysis was performed to predict CMD. Results: FFR, invasive wire-derived coronary flow reserve (CFRwire) and index of microcirculatory resistance were 0.68 [interquartile range (IQR), 0.59-0.74], 1.71 (IQR, 1.24-2.88), and 22.6 (IQR, 15.1-34.5), respectively. The rest and hyperemic-myocardial blood flow (MBF) and CT-MP-derived CFR (CFRCT-MP) were 0.83 (0.64-1.03) mL/min/g, 2.14 (1.30-2.92) mL/min/g, and 2.19 (1.44-3.37), respectively. In the territories with CMD, hyperemic-MBF was significantly lower than in those without [1.68 (IQR, 0.84-2.44) vs. 2.31 (IQR, 1.67-3.34) mL/min/g, P=0.015] and the prevalence of CFRCT-MP <2.0 was higher in the lesions with CMD than in those without (62.1% vs. 28.2%, P=0.011), while FFR values were similar. Fibrofatty and necrotic core component volume was greater in the vessels with CMD than in those without [31.8 (IQR, 19.0-48.9) vs. 25.1 (IQR, 17.2-32.1) mm3, P=0.045]. Multivariable logistic regression analysis showed that hyperemic-MBF and fibrofatty and necrotic core component volume were independent predictors of CMD territories [odds ratio (OR) =0.583; 95% confidence interval (CI): 0.355-0.958; P=0.033 and OR =1.040; 95% CI: 1.010-1.070; P=0.011]. Conclusions: Quantitative assessment of absolute coronary flow using pre-percutaneous coronary intervention (PCI) CT-MP, and comprehensive plaque analysis using computed tomography angiography may help detect coexisting subtended microvascular dysfunction in territories with functionally significant epicardial coronary lesions. Further studies are required to elucidate the clinical significance of coexisting CMD in patients with CCS undergoing PCI.

Diagnosis and Prognostic Value of the Underlying Cause of Acute Coronary Syndrome in Optical Coherence Tomography-Guided Emergency Percutaneous Coronary Intervention.

Background The prognostic impact of optical coherence tomography-diagnosed culprit lesion morphology in acute coronary syndrome (ACS) has not been systematically examined in real-world settings. Methods and Results This investigator-initiated, prospective, multicenter, observational study was conducted at 22 Japanese hospitals to identify the prevalence of underlying ACS causes (plaque rupture [PR], plaque erosion [PE], and calcified nodules [CN]) and their impact on clinical outcomes. Patients with ACS diagnosed within 24 hours of symptom onset undergoing emergency percutaneous coronary intervention were enrolled. Optical coherence tomography-guided percutaneous coronary intervention recipients were assessed for underlying ACS causes and followed up for major adverse cardiac events (cardiovascular death, myocardial infarction, heart failure, or ischemia-driven revascularization) at 1 year. Of 1702 patients with ACS, 702 (40.7%) underwent optical coherence tomography-guided percutaneous coronary intervention for analysis. PR, PE, and CN prevalence was 59.1%, 25.6%, and 4.0%, respectively. One-year major adverse cardiac events occurred most frequently in patients with CN (32.1%), followed by PR (12.4%) and PE (6.2%) (log-rank P<0.0001), primarily driven by increased cardiovascular death (CN, 25.0%; PR, 0.7%; PE, 1.1%; log-rank P<0.0001) and heart failure trend (CN, 7.1%; PR, 6.8%; PE, 2.2%; log-rank P<0.075). On multivariate Cox regression analysis, the underlying ACS cause was associated with 1-year major adverse cardiac events (CN [hazard ratio (HR), 4.49 [95% CI, 1.35-14.89], P=0.014]; PR (HR, 2.18 [95% CI, 1.05-4.53], P=0.036]; PE as reference). Conclusions Despite being the least common, CN was a clinically significant underlying ACS cause, associated with the highest future major adverse cardiac events risk, followed by PR and PE. Future studies should evaluate the possibility of ACS underlying cause-based optical coherence tomography-guided optimization.

Prognostic Implications of Fractional Flow Reserve and Coronary Flow Reserve After Drug-Eluting Stent Implantation.

BACKGROUND: Fractional flow reserve (FFR) after percutaneous coronary intervention (PCI) provides prognostic information, but limited data are available regarding prognostication using post-PCI coronary flow reserve (CFR). In this study we aimed to assess the prognostic value of post-procedural FFR and CFR for target vessel failure (TVF) after PCI.Methods and Results: This lesion-based post-hoc pooled analysis of previously published registry data involved 466 patients with chronic coronary syndrome with single-vessel disease who underwent pre- and post-PCI FFR and CFR measurements, and were followed-up to determine the predictors of TVF. The prognostic value of post-PCI CFR and FFR was compared with that of FFR or CFR alone. Post-PCI FFR/CFR discordant results were observed in 42.5%, and 10.3% of patients had documented TVF. Receiver-operating characteristic curve analysis revealed that the optimal cutoff values of post-PCI FFR and CFR to predict the occurrence of TVF were 0.85 and 2.26, respectively. Significant differences in TVF were detected according to post-PCI FFR (≤0.85 vs. >0.85, P=0.007) and post-PCI CFR (<2.26 vs. ≥2.26, P<0.001). Post-PCI FFR ≤0.85 and post-PCI CFR <2.26 were independent prognostic predictors. CONCLUSIONS: After PCI completion, discordant results between FFR and CFR were not uncommon. Post-PCI CFR categorization showed incremental prognostic value for predicting TVF independent of post-PCI FFR risk stratification.

Prognostic utility of the pericoronary fat attenuation index in patients with takotsubo cardiomyopathy.

BACKGROUND: The etiology of takotsubo cardiomyopathy (TCM) remains poorly understood and no optimal management strategy has been established. Identification of features associated with poor outcomes may improve the prognosis of patients with TCM. We aimed to identify the predictors of poor prognosis in patients with TCM using coronary computed tomography angiography (CCTA). METHODS: We enrolled consecutive patients with TCM who underwent CCTA during the acute disease phase. The pericoronary fat attenuation index (FAI) of adipose tissue was obtained from CCTA images. Major adverse cardiac and cerebrovascular events (MACCE) were defined as all-cause death, non-fatal myocardial infarction, stroke, rehospitalization due to congestive heart failure, and TCM recurrence. The relationships between patient characteristics and CCTA findings were compared between patients with and without MACCE. RESULTS: A total of 52 patients were included (10 men [19.2%]; mean age, 71 years). After a median follow-up of 23 months, MACCE had developed in 10 patients (19.2%). There were significant differences in clinical characteristics [including the three-vessel mean FAI (FAI-mean)] between patients with and without MACCE. Univariate Cox regression analyses showed that FAI-mean â€‹≥ â€‹-68.94 Hounsfield units (cut-off value derived from receiver operating characteristic curve analysis) (hazard ratio [HR], 13.52; 95% confidence interval [CI], 1.705-107.2; p â€‹= â€‹0.014) and NT-proBNP (HR, 1.000; 95% CI, 1.000-1.000; p â€‹= â€‹0.022) were significant predictors of MACCE. FAI-mean â€‹≥ â€‹-68.94 HU was significantly associated with MACCE (chi-squared statistic â€‹= â€‹10.3, p â€‹= â€‹0.001). CONCLUSION: In patients with TCM, a higher FAI-mean was significantly associated with poorer outcomes independent of the conventional risk factors.

Cardiovascular Risk Factors and Culprit Plaque Characteristics in Women With Acute Coronary Syndromes.

Outcomes after myocardial infarction in women remain poor. The number of cardiovascular risk factors in women increase with age, however the relation between risk factors and culprit plaque characteristics in this population is poorly understood. The aim of the study was to investigate the relation between risk factors and culprit plaque characteristics in women with acute coronary syndrome (ACS). A total of 382 women who presented with ACS and underwent pre-intervention optical coherence tomography imaging of the culprit lesion were included in this analysis. The culprit plaques were categorized as plaque rupture, plaque erosion or calcified plaque, and then stratified by age and risk factors. The predominant pathology of ACS was plaque erosion in young patients (<60 years), which decreased with age (p <0.001). Current smokers had a high prevalence of plaque rupture (60%) and lipid plaque (79%). Women with diabetes tended to have more lipid plaque (70%) even at a young age. In women with hyperlipidemia, the prevalence of lipid plaques was modest in younger ages, but rose gradually with age (p <0.001). An increasing age trend for lipid plaque was also observed in women with hypertension (p = 0.03) and current smokers (p = 0.01). In conclusion, early treatment of risk factors such as diabetes in young women might be important before accelerated progression of atherosclerosis begins as age advances. Clinical trial registration: http://www.clinicaltrials.gov, NCT01110538, NCT03479723 and NCT02041650.

Prognostic implications of unrecognized myocardial infarction and periprocedural myocardial injury on cardiac magnetic resonance imaging in patients with chronic coronary syndrome.

This study sought to evaluate the prognostic implications of the presence of preprocedural unrecognized myocardial infarction (UMI) and periprocedural myocardial injury (PMI) evaluated by delayed gadolinium enhancement cardiac magnetic resonance (DE-CMR) in patients with chronic coronary syndrome (CCS) undergoing elective percutaneous coronary intervention (PCI). We enrolled 250 CCS patients scheduled for elective PCI. UMI was defined as the presence of late gadolinium enhancement (LGE) detected by pre-PCI CMR in the region without medical history of revascularization and/or MI. Periprocedural new occurrence or increased volume of LGE in the target territory detected by post-PCI CMR (PPL) were used to assess PMI. In the final analysis of 235 patients, UMI and PPL were detected in 43 patients (18.3%) and 45 patients (19.1%), respectively. During follow-up for a median of 2.2 years, major adverse cardiac events (MACE) occurred in 31 (13.2%) patients. On multivariable analysis, UMI and PPL remained as significant predictors of MACE after adjusting confounding factors (HR 4.62, 95% CI 2.24-9.54, P < 0.001, HR 2.33, 95% CI 1.11-4.91, P = 0.026). In patients with CCS who underwent elective PCI, UMI and PPL were independent predictors of worse outcomes. UMI and PPL on DE-CMR might provide additional potential insight for the risk stratification of patients undergoing elective PCI.

Optical Coherence Tomography-Guided Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction: Rationale and Design of the ATLAS-OCT Study.

Even after successful revascularization with primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI), subsequent adverse events still occur. Previous studies have suggested potential benefits of intravascular imaging, including optical coherence tomography (OCT). However, the feasibility of OCT-guided primary PCI has not been systematically examined in these patients. The ATLAS-OCT (ST-elevation Acute myocardial infarcTion and cLinicAl outcomeS treated by Optical Coherence Tomography-guided percutaneous coronary intervention) trial was designed to investigate the feasibility of OCT guidance during primary PCI for STEMI in experienced centers with expertise on OCT-guided PCI as a prospective, multicenter registry of consecutive patients with STEMI who underwent a primary PCI. The sites' inclusion criteria are as follows: (1) acute care hospitals providing 24/7 emergency care for STEMI, and (2) institutions where OCT-guided PCI is the first choice for primary PCI in STEMI. All patients with STEMI who underwent primary PCI at participating sites will be consecutively enrolled, irrespective of OCT use during PCI. The primary end point will be the rate of successful OCT imaging during the primary PCI. As an ancillary imaging modality to angiography, OCT provides morphologic information during PCI for the assessment of plaque phenotypes, vessel sizing, and PCI optimization. Major adverse cardiac events, defined as a composite of all-cause death, myocardial infarction, and target vessel revascularization at 1 year, will also be recorded. The ATLAS-OCT study will clarify the feasibility of OCT-guided primary PCI for patients with STEMI and further identify a suitable patient group for OCT-guided primary PCI.

Sex Differences in Coronary Atherosclerotic Phenotype and Healing Pattern on Optical Coherence Tomography Imaging.

BACKGROUND: Layered plaque, a signature of previous plaque disruption, is a known predictor of rapid plaque progression. Layered plaque can be identified in vivo by optical coherence tomography. Studies have reported differences in plaque burden between women and men, but sex differences in the pattern of layered plaque are unknown. METHODS: Preintervention optical coherence tomography images of 533 patients with chronic coronary syndromes were analyzed. Detailed plaque characteristics of layered and nonlayered plaques of the target lesion were compared between men and women. RESULTS: The prevalence of layered plaque was similar between men (N=418) and women (N=115; 55% versus 54%; P=0.832). In men, more features of plaque vulnerability were identified in layered plaque than in nonlayered plaque: lipid plaque (87% versus 69%; P<0.001), macrophages (69% versus 56%; P=0.007), microvessels (72% versus 39%; P<0.001), and cholesterol crystals (49% versus 30%; P<0.001). No difference in plaque vulnerability between layered and nonlayered plaques was observed in women. Layered plaque in men had more features consistent with previous plaque rupture than in women: interrupted pattern (74% versus 52%; P<0.001) and a greater layer index (1198 [781-1835] versus 943 [624-1477]; P<0.001). CONCLUSIONS: In men, layered plaques exhibit more features of vascular inflammation and vulnerability as well as evidence of previous plaque rupture, compared with nonlayered plaques, whereas in women, no difference was observed between layered and nonlayered plaques. Vascular inflammation (plaque rupture) may be the predominant mechanism of layered plaque in men, whereas a less inflammatory mechanism may play a key role in women. REGISTRATION: URL: http://www. CLINICALTRIALS: gov; Unique Identifier: NCT01110538, NCT04523194.

Multimodality coronary imaging to predict non-culprit territory unrecognized myocardial infarction in Non-ST-Elevation acute coronary syndrome.

PURPOSE: Unrecognized myocardial infarction (UMI) detected by cardiac magnetic resonance (CMR) imaging is associated with adverse outcomes in patients with acute and chronic coronary syndrome. This study aimed to assess the predictors of optical coherence tomography (OCT) and coronary computed tomography angiography (CCTA) findings for non-infarct-related (non-IR) territory UMI in patients presenting with non-ST-elevation acute coronary syndrome (NSTE-ACS). METHODS: We investigated 69 patients with a first clinical episode of NSTE-ACS who underwent pre-percutaneous coronary intervention (PCI) 320-slice CCTA, uncomplicated urgent PCI with OCT assessment within 24 h of admission, and post-PCI CMR. UMI was assessed using late gadolinium enhancement to identify regions of hyperenhancement with an ischemic distribution pattern in non-IR territories. RESULTS: Non-IR UMI was detected in 11 patients (15.9%). Lower ejection fraction, higher Gensini score, higher Agatston score, high pericoronary adipose tissue attenuation (PCATA), OCT-defined culprit lesion plaque rupture, and OCT-defined culprit lesion cholesterol crystal were significantly associated with the presence of non-IR UMI. On dividing the total cohort was divided into five groups according to the numbers of two OCT-derived risk factors and two CCTA-derived risk factors, the frequency of non-IR UMI frequency significantly increased according to the number of these relevant risk features (p < 0.001). Patients with all of the non-IR UMI risk factors showed 50% prevalence of non-IR UMI, compared with 2.2% of patients with low risk factors (≤ 2). CONCLUSIONS: Integrated CCTA and culprit lesion OCT assessment may help identify the presence of non-IR UMI, potentially providing prognostic information in patients with first NSTE-ACS episode.

Prognostic implications of non-infarct-related territory unrecognized myocardial infarction in patients with non-ST-segment-elevation acute coronary syndrome.

BACKGROUND: Prognostic value of non-infarct-related territory (non-IR) unrecognized myocardial infarction (UMI) in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) remains to be elucidated. We sought to evaluate the prognostic impact of non-IR UMI in patients with first NSTE-ACS presentation. METHODS: This retrospective single-center analysis was conducted in patients with NSTE-ACS without prior history of coronary artery disease, who underwent uncomplicated urgent percutaneous coronary intervention (PCI) within 48 h of admission between August 2014 and January 2018. All patients underwent postprocedural cardiac magnetic resonance imaging (CMR) within 30 days after PCI. Non-IR UMI was defined as the presence of non-IR delayed gadolinium enhancement with an ischemic distribution pattern. We investigated the association of non-IR UMI, other CMR findings and baseline clinical characteristics with major adverse cardiac events (MACE), defined as death, non-fatal myocardial infarction, stroke, late revascularization, and hospitalization for congestive heart failure. RESULTS: A total of 168 NSTE-ACS patients were included [124 men (73.8 %); 66 ±â€¯11 years]. Non-IR UMI was detected in 28 patients (16.7 %). During a median follow-up of 32 (15-58) months, MACE occurred in 10 (35.7 %) patients with non-IR UMI, and 20 (14.3 %) patients without (p = 0.013). Cox's proportional hazards analysis showed that the presence of non-IR UMI was an independent predictor of MACE (hazard ratio [HR], 2.37, 95 % confidence interval [CI], 1.09-5.18, p = 0.030). In patients with NSTE-ACS undergoing urgent PCI, the prevalence of non-IR UMI was 16.7 %. CONCLUSIONS: Non-IR UMI provided prognostic information independent of conventional risk factors and the extent of myocardial injury caused by NSTE-ACS.

Identification of Optical Coherence Tomography-Defined Coronary Plaque Erosion by Preprocedural Computed Tomography Angiography.

Background A previous coronary computed tomography (CT) angiographic study failed to discriminate optical coherence tomography-defined intact fibrous cap culprit lesions (IFC group) from those with ruptured fibrous caps (RFC group) in patients with coronary artery disease. This study aimed to evaluate the diagnostic efficacy of preprocedural coronary CT imaging in identifying subsequently performed optical coherence tomography-defined plaque rupture or erosion at culprit lesions in patients with non-ST-segment-elevation acute myocardial infarction. Methods and Results This study used data from 2 recently published studies that tested the hypothesis that coronary CT angiography (CCTA) before percutaneous coronary intervention may provide diagnostic information on the high-risk atherosclerotic burden in patients with non-ST-segment-elevation acute myocardial infarction. In the analysis of 186 patients, optical coherence tomography identified 106 RFC plaques and 80 IFC plaques as the culprit lesions. On CT, the prevalence of low-attenuation plaque, positive remodeling, napkin-ring sign, and spotty calcification were all significantly lower in the IFC group. The culprit vessel pericoronary adipose tissue inflammation and coronary artery calcium scores were significantly lower in the IFC group than in the RFC group. The absence of low-attenuation plaque, napkin-ring sign, zero coronary artery calcium, and low pericoronary adipose tissue inflammation were independent predictors of IFC. When stratified into 5 subgroups according to the number of these 4 CT factors, the prevalence of IFC was 8.3%, 20.8%, 44.6%, 75.6%, and 100% (P<0.001), respectively. Conclusions Preprocedural comprehensive coronary CT imaging, including coronary artery calcium and pericoronary adipose tissue inflammation assessment, can accurately and noninvasively identify optical coherence tomography-defined IFC or RFC culprit lesions.

Relationship of OCT-defined plaque characteristics with CCTA-derived coronary inflammation and CMR-derived global coronary flow reserve in patients with acute coronary syndrome.

BACKGROUND: The relationship of layered plaque detected by optical coherence tomography (OCT) with coronary inflammation and coronary flow reserve (CFR) remains elusive. We aimed to investigate the association of OCT-defined layered plaque with pericoronary adipose tissue (PCAT) inflammation assessed by coronary computed tomography angiography (CCTA) and global (G)-CFR assessed by cardiac magnetic resonance imaging (CMR) in patients with acute coronary syndrome (ACS). METHODS: We retrospectively investigated 88 patients with first ACS who underwent preprocedural CCTA, OCT imaging of the culprit lesion prior to primary/urgent percutaneous coronary intervention (PCI), and postprocedural CMR. All patients were divided into two groups according to the presence and absence of OCT-defined layered plaque at the culprit lesion. Coronary inflammation was assessed by the mean value of PCAT attenuation (-190 to -30 HU) of the three major coronary vessels. G-CFR was obtained by quantifying absolute coronary sinus flow at rest and during maximum hyperemia. CCTA and CMR findings were compared between the groups. RESULTS: In a total of 88 patients, layered plaque was detected in 51 patients (58.0%). The patients with layered plaque had higher three-vessel-PCAT attenuation value (-68.58 ± 6.41 vs. -71.60 ± 5.21 HU, P = 0.021) and culprit vessel-PCAT attenuation value (-67.69 ± 7.76 vs. -72.07 ± 6.57 HU, P = 0.007) than those with non-layered plaque. The patients with layered plaque had lower G-CFR value (median, 2.26 [interquartile range, 1.78, 2.89] vs. 3.06 [2.41, 3.90], P = 0.003) than those with non-layered plaque. CONCLUSIONS: The presence of OCT-defined layered plaque at the culprit lesion was associated with high PCAT attenuation and low G-CFR after primary/urgent PCI in patients with ACS. OCT assessment of culprit plaque morphology and detection of layered plaque may help identify increased pericoronary inflammation and impaired CFR, potentially providing the risk stratification in patients with ACS and residual microvascular dysfunction after PCI.