Plaque Rupture,Compared With Plaque Erosion,Is Associated With a Higher Level of Pancoronary Inflammation

ObjectivesThe aim of this study was to compare the level of coronary inflammation between plaque rupture and plaque erosion using pericoronary adipose tissue (PCAT) attenuation.BackgroundVascular inflammation plays a key role in plaque rupture, while the role of inflammation in plaque erosion remains less well defined. PCAT attenuation determined using computed tomography has emerged as a marker specific for coronary artery inflammation.MethodsPatients with non–ST-segment elevation acute coronary syndromes who underwent preintervention coronary computed tomographic angiography and optical coherence tomographic culprit lesion imaging were enrolled. PCAT attenuation was measured around the culprit lesion and in the proximal 40 mm of all coronary arteries.ResultsAmong 198 patients, plaque rupture was the underlying mechanism in 107 (54.0%) and plaque erosion in 91 (46.0%). Plaque rupture had higher PCAT attenuation than plaque erosion both at the culprit plaque level (?65.8 ± 7.5 HU vs ?69.5 ± 11.4 HU; P = 0.010) and at the culprit vessel level (?67.1 ± 7.1 HU vs ?69.6 ± 8.2 HU; P = 0.024). The mean PCAT attenuation of all 3 coronary arteries was also significantly higher in patients with plaque rupture than in plaque erosion, indicating a higher level of inflammation (?67.9 ± 5.7 HU vs ?69.9 ± 6.8 HU; P = 0.030). In multivariable analysis, plaque rupture was significantly associated with high PCAT attenuation.ConclusionsPCAT attenuation in culprit plaque, culprit vessel, and all 3 coronary arteries was higher in plaque rupture than in plaque erosion. The results suggest that pancoronary inflammation plays a more significant role in plaque rupture than in plaque erosion. (Massachusetts General Hospital and Tsuchiura Kyodo General Hospital Coronary Imaging Collaboration; NCT04523194)     

Plaque Burden and 1-Year Outcomes in Acute Chest Pain: Results From the Multicenter RAPID-CTCA Trial

BackgroundIn patients with stable chest pain, computed tomography (CT) plaque burden is an independent predictor of future coronary events.ObjectivesThe purpose of this study was to determine whether plaque burden and characteristics can predict subsequent death or myocardial infarction in patients with acute chest pain.MethodsIn a post hoc analysis of a multicenter trial of early coronary CT angiography, the authors performed quantitative plaque analysis to assess the association between primary endpoint of 1-year all-cause death or nonfatal myocardial infarction and the GRACE (Global Registry of Acute Coronary Events) score, presence of obstructive coronary artery disease, and plaque burden in 404 patients with suspected acute coronary syndrome.ResultsFollowing the index event, 25 patients had a primary event that was associated with a higher GRACE score (134 ± 44 vs 113 ± 35; P = 0.012), larger burdens of total (46% [IQR: 43%-50%] vs 36% [IQR: 21%-46%]; P < 0.001), noncalcified (41% [IQR: 37%-%47] vs 33% [IQR: 20%-41%]; P < 0.001), and low-attenuation plaque (4.22% [IQR: 3.3%-5.68%] vs 2.14% [IQR: 0.5%-4.88%]; P < 0.001), but not obstructive coronary artery disease (P = 0.065). Total, noncalcified, and low-attenuation plaque burden were the strongest predictors of future events independent of GRACE score and obstructive coronary artery disease (P ≤ 0.002 for all). Patients with a low-attenuation burden above the median had nearly an 8-fold increased risk of the primary endpoint (HR: 7.80 [95% CI: 2.33-26.0]; P < 0.001), outperforming either a GRACE score of >140 (HR: 3.80 [95% CI :1.45-6.98]; P = 0.004) or obstructive coronary artery disease (HR: 2.07 [95% CI: 0.94-4.53]; P = 0.07).ConclusionsIn patients with suspected acute coronary syndrome, low-attenuation plaque burden is a major predictor of 1-year death or recurrent myocardial infarction. (Rapid Assessment of Potential Ischaemic Heart Disease With CTCA [RAPID-CTCA]; NCT02284191)     

Peri-Coronary Adipose Tissue Density Is Associated With 18F-Sodium Fluoride Coronary Uptake in Stable Patients With High-Risk Plaques

ObjectivesThis study aimed to assess the association between increased lesion peri-coronary adipose tissue (PCAT) density and coronary ¹⁸F-sodium fluoride (¹⁸F-NaF) uptake on positron emission tomography (PET) in stable patients with high-risk coronary plaques (HRPs) shown on coronary computed tomography angiography (CTA).BackgroundCoronary ¹⁸F-NaF uptake reflects the rate of calcification of coronary atherosclerotic plaque. Increased PCAT density is associated with vascular inflammation. Currently, the relationship between increased PCAT density and ¹⁸F-NaF uptake in stable patients with HRPs on coronary CTA has not been characterized.MethodsPatients who underwent coronary CTA were screened for HRP, which was defined by 3 concurrent plaque features: positive remodeling; low attenuation plaque (LAP) (<30 Hounsfield units [HU]) and spotty calcification; and obstructive coronary stenosis ≥50% (plaque volume >100 mm³). Patients with HRPs were recruited to undergo ¹⁸F-NaF PET/CT. In lesions with stenosis ≥25%, quantitative plaque analysis, mean PCAT density, maximal coronary motion−corrected ¹⁸F-NaF standard uptake values (SUVmax), and target-to-background ratios (TBR) were measured.ResultsForty-one patients (age 65 ± 6 years; 68% men) were recruited. Fifty-one lesions in 23 patients (56%) showed increased coronary ¹⁸F-NaF activity. Lesions with ¹⁸F-NaF uptake had higher surrounding PCAT density than those without ¹⁸F-NaF uptake (−73 HU; interquartile range −79 to −68 HU vs. −86 HU; interquartile range −94 to −80 HU; p < 0.001). ¹⁸F-NaF TBR and SUVmax were correlated with PCAT density (r = 0.63 and r = 0.68, respectively; all p < 0.001). On adjusted multiple regression analysis, increased lesion PCAT density and LAP volume were associated with ¹⁸F-NaF TBR (β = 0.25; 95% confidence interval: 0.17 to 0.34; p < 0.001 for PCAT, and β = 0.07; 95% confidence interval: 0.03 to 0.11; p = 0.002 for LAP).ConclusionsIn patients with HRP features on coronary CTA, increased density of PCAT was associated with focal ¹⁸F-NaF PET uptake. Simultaneous assessment of these imaging biomarkers by ¹⁸F-NaF PET and CTA might refine cardiovascular risk prediction in stable patients with HRP features.     

Myocardial Infarction Associates With a Distinct Pericoronary Adipose Tissue Radiomic Phenotype: A Prospective Case-Control Study

ObjectivesThis study sought to determine whether coronary computed tomography angiography (CCTA)-based radiomic analysis of pericoronary adipose tissue (PCAT) could distinguish patients with acute myocardial infarction (MI) from patients with stable or no coronary artery disease (CAD).BackgroundImaging of PCAT with CCTA enables detection of coronary inflammation. Radiomics involves extracting quantitative features from medical images to create big data and identify novel imaging biomarkers.MethodsIn a prospective case-control study, 60 patients with acute MI underwent CCTA within 48 h of admission, before invasive angiography. These subjects were matched to patients with stable CAD (n = 60) and controls with no CAD (n = 60) by age, sex, risk factors, medications, and CT tube voltage. PCAT was segmented around the proximal right coronary artery (RCA) in all patients and around culprit and nonculprit lesions in patients with MI. PCAT segmentations were analyzed using Radiomics Image Analysis software.ResultsOf 1,103 calculated radiomic parameters, 20.3% differed significantly between MI patients and controls, and 16.5% differed between patients with MI and stable CAD (critical p < 0.0006); whereas none differed between patients with stable CAD and controls. On cluster analysis, the most significant radiomic parameters were texture or geometry based. At 6 months post-MI, there was no significant change in the PCAT radiomic profile around the proximal RCA or nonculprit lesions. Using machine learning (XGBoost), a model integrating clinical features (risk factors, serum lipids, high-sensitivity C-reactive protein), PCAT attenuation, and radiomic parameters provided superior discrimination of acute MI (area under the receiver operator characteristic curve [AUC]: 0.87) compared with a model with clinical features and PCAT attenuation (AUC: 0.77; p = 0.001) or clinical features alone (AUC: 0.76; p < 0.001).ConclusionsPatients with acute MI have a distinct PCAT radiomic phenotype compared with patients with stable or no CAD. Using machine learning, a radiomics-based model outperforms a PCAT attenuation-based model in accurately identifying patients with MI.     

Prognostic Value of RCA Pericoronary Adipose Tissue CT-Attenuation Beyond High-Risk Plaques,Plaque Volume,and Ischemia

ObjectivesThis study was designed to assess the prognostic value of pericoronary adipose tissue computed tomography attenuation (PCATa) beyond quantitative coronary computed tomography angiography (CCTA)–derived plaque volume and positron emission tomography (PET) determined ischemia.BackgroundInflammation plays a crucial role in atherosclerosis. PCATa has been shown to assess coronary-specific inflammation and is of prognostic value in patients with suspected coronary artery disease (CAD).MethodsA total of 539 patients who underwent CCTA and [¹⁵O]H₂O PET perfusion imaging because of suspected CAD were included. Imaging assessment included coronary artery calcium score (CACS), presence of obstructive CAD (≥50% stenosis) and high-risk plaques (HRPs), total plaque volume (TPV), calcified/noncalcified plaque volume (CPV/NCPV), PCATa, and myocardial ischemia. The endpoint was a composite of death and nonfatal myocardial infarction. Prognostic thresholds were determined for quantitative CCTA variables.ResultsDuring a median follow-up of 5.0 (interquartile range: 4.7 to 5.0) years, 33 events occurred. CACS >59 Agatston units, obstructive CAD, HRPs, TPV >220 mm³, CPV >110 mm³, NCPV >85 mm³, and myocardial ischemia were associated with shorter time to the endpoint with unadjusted hazard ratios (HRs) of 4.17 (95% confidence interval [CI]: 1.80 to 9.64), 4.88 (95% CI: 1.88 to 12.65), 3.41 (95% CI: 1.72 to 6.75), 7.91 (95% CI: 3.05 to 20.49), 5.82 (95% CI: 2.40 to 14.10), 8.07 (95% CI: 3.33 to 19.55), and 4.25 (95% CI: 1.84 to 9.78), respectively (p < 0.05 for all). Right coronary artery (RCA) PCATa above scanner specific thresholds was associated with worse prognosis (unadjusted HR: 2.84; 95% CI: 1.44 to 5.63; p = 0.003), whereas left anterior descending artery and circumflex artery PCATa were not related to outcome. RCA PCATa above scanner specific thresholds retained is prognostic value adjusted for imaging variables and clinical characteristics associated with the endpoint (adjusted HR: 2.45; 95% CI: 1.23 to 4.93; p = 0.011).ConclusionsParameters associated with atherosclerotic burden and ischemia were more strongly associated with outcome than RCA PCATa. Nonetheless, RCA PCATa was of prognostic value beyond clinical characteristics, CACS, obstructive CAD, HRPs, TPV, CPV, NCPV, and ischemia.     

Impact of Diabetes on Outcome With Drug-Coated Balloons Versus Drug-Eluting Stents: The BASKET-SMALL 2 Trial

ObjectivesThe study sought to evaluate the impact of diabetes mellitus on 3-year clinical outcome in patients undergoing drug-coated balloon (DCB) or drug-eluting stent (DES) treatment for de novo lesions.BackgroundFor treatment of de novo coronary small vessel disease, DCBs are noninferior to DES.MethodsIn this prespecified analysis of a multicenter, randomized, noninferiority trial, including 758 patients with de novo lesions in coronary vessels <3 mm who were randomized 1:1 to DCB or DES and followed over 3 years for major adverse cardiac events (MACE) (cardiac death, nonfatal myocardial infarction [MI], and target vessel revascularization [TVR]), outcome was analyzed regarding the presence or absence of diabetes mellitus.ResultsIn nondiabetic patients (n = 506), rates of MACE (DCB 13.0% vs DES 11.5%; hazard ratio [HR]: 1.24; 95% confidence interval [CI]: 0.73-2.09; P = 0.43), cardiac death (2.8% vs 2.9%; HR: 0.97; 95% CI: 0.32-2.92; P = 0.96), nonfatal MI (5.1% vs 4.8%; HR: 1.00; 95% CI: 0.44-2.28; P = 0.99), and TVR (8.8% vs 6.1%; HR: 1.64; 95% CI: 0.83-3.25; P = 0.16) were similar. In diabetic patients (n = 252), rates of MACE (19.3% vs 22.2%; HR: 0.82; 95% CI: 0.45-1.48; P = 0.51), cardiac death (8.8% vs 5.9%; HR: 2.01; 95% CI: 0.76-5.31; P = 0.16), and nonfatal MI (7.1% vs 9.8%; HR: 0.55; 95% CI: 0.21-1.49; P = 0.24) were similar in DCB and DES. TVR was significantly lower with DCBs vs DES (9.1% vs 15.0%; HR: 0.40; 95% CI: 0.17-0.94; P = 0.036; P = 0.011 for interaction).ConclusionsThe rates of MACE are similar in DCBs and DES in de novo coronary lesions of diabetic and nondiabetic patients. In diabetic patients, need for TVR was significantly lower with DCB versus DES. (Basel Stent Kosten Effektivitäts Trial Drug Eluting Balloons vs Drug Eluting Stents in Small Vessel Interventions [BASKET-SMALL2]; NCT01574534)     

Thoracic Aortic 18F-Sodium Fluoride Activity and Ischemic Stroke in Patients With Established Cardiovascular Disease

BackgroundAortic atherosclerosis represents an important contributor to ischemic stroke risk. Identifying patients with high-risk aortic atheroma could improve preventative treatment strategies for future ischemic stroke.ObjectivesThe purpose of this study was to investigate whether thoracic ¹⁸F-sodium fluoride positron emission tomography (PET) could improve the identification of patients at the highest risk of ischemic stroke.MethodsIn a post hoc observational cohort study, we quantified thoracic aortic and coronary ¹⁸F-sodium fluoride activity in 461 patients with stable cardiovascular disease undergoing PET combined with computed tomography (CT). Progression of atherosclerosis was assessed by change in aortic and coronary CT calcium volume. Clinical outcomes were determined by the occurrence of ischemic stroke and myocardial infarction. We compared the prognostic utility of ¹⁸F-sodium fluoride activity for predicting stroke to clinical risk scores and CT calcium quantification using survival analysis and multivariable Cox regression.ResultsAfter 12.7 ± 2.7 months, progression of thoracic aortic calcium volume correlated with baseline thoracic aortic ¹⁸F-sodium fluoride activity (n = 140; r = 0.31; P = 0.00016). In 461 patients, 23 (5%) patients experienced an ischemic stroke and 32 (7%) a myocardial infarction after 6.1 ± 2.3 years of follow-up. High thoracic aortic ¹⁸F-sodium fluoride activity was strongly associated with ischemic stroke (HR: 10.3 [95% CI: 3.1-34.8]; P = 0.00017), but not myocardial infarction (P = 0.40). Conversely, high coronary ¹⁸F-sodium fluoride activity was associated with myocardial infarction (HR: 4.8 [95% CI: 1.9-12.2]; P = 0.00095) but not ischemic stroke (P = 0.39). In a multivariable Cox regression model including imaging and clinical risk factors, thoracic aortic ¹⁸F-sodium fluoride activity was the only variable associated with ischemic stroke (HR: 8.19 [95% CI: 2.33-28.7], P = 0.0010).ConclusionsIn patients with established cardiovascular disease, thoracic aortic ¹⁸F-sodium fluoride activity is associated with the progression of atherosclerosis and future ischemic stroke. Arterial ¹⁸F-sodium fluoride activity identifies localized areas of atherosclerotic disease activity that are directly linked to disease progression and downstream regional clinical atherothrombotic events. (DIAMOND–Dual Antiplatelet Therapy to Reduce Myocardial Injury [DIAMOND], NCT02110303; Study Investigating the Effect of Drugs Used to Treat Osteoporosis on the Progression of Calcific Aortic Stenosis [SALTIRE II], NCT02132026; Novel Imaging Approaches To Identify Unstable Coronary Plaques, NCT01749254; and Role of Active Valvular Calcification and Inflammation in Patients With Aortic Stenosis, NCT01358513)     

Coronary 18F-Sodium Fluoride Uptake Predicts Outcomes in Patients With Coronary Artery Disease

BackgroundReliable methods for predicting myocardial infarction in patients with established coronary artery disease are lacking. Coronary ¹⁸F-sodium fluoride (¹⁸F-NaF) positron emission tomography (PET) provides an assessment of atherosclerosis activity.ObjectivesThis study assessed whether ¹⁸F-NaF PET predicts myocardial infarction and provides additional prognostic information to current methods of risk stratification.MethodsPatients with known coronary artery disease underwent ¹⁸F-NaF PET computed tomography and were followed up for fatal or nonfatal myocardial infarction over 42 months (interquartile range: 31 to 49 months). Total coronary ¹⁸F-NaF uptake was determined by the coronary microcalcification activity (CMA).ResultsIn a post hoc analysis of data collected for prospective observational studies, the authors studied 293 study participants (age: 65 ± 9 years; 84% men), of whom 203 (69%) showed increased coronary ¹⁸F-NaF activity (CMA >0). Fatal or nonfatal myocardial infarction occurred only in patients with increased coronary ¹⁸F-NaF activity (20 of 203 with a CMA >0 vs. 0 of 90 with a CMA of 0; p < 0.001). On receiver operator curve analysis, fatal or nonfatal myocardial infarction prediction was highest for ¹⁸F-NaF CMA, outperforming coronary calcium scoring, modified Duke coronary artery disease index and Reduction of Atherothrombosis for Continued Health (REACH) and Secondary Manifestations of Arterial Disease (SMART) risk scores (area under the curve: 0.76 vs. 0.54, 0.62, 0.52, and 0.54, respectively; p < 0.001 for all). Patients with CMA >1.56 had a >7-fold increase in fatal or nonfatal myocardial infarction (hazard ratio: 7.1; 95% confidence interval: 2.2 to 25.1; p = 0.003) independent of age, sex, risk factors, segment involvement and coronary calcium scores, presence of coronary stents, coronary stenosis, REACH and SMART scores, the Duke coronary artery disease index, and recent myocardial infarction.ConclusionsIn patients with established coronary artery disease, ¹⁸F-NaF PET provides powerful independent prediction of fatal or nonfatal myocardial infarction.     

Association of Sex,Reduced Myocardial Flow Reserve,and Long-Term Mortality Across Spectrum of Atherosclerotic Disease

BackgroundCoronary vasomotor dysfunction (defined by reduced myocardial blood flow reserve [MBFR]) is associated with high cardiac risk in both men and women in absence of significant coexisting epicardial disease. Whether there is a sex-specific difference in prognostic value of reduced MBFR in patients with a greater burden of coexisting epicardial atherosclerotic disease is not well understood.ObjectivesThe purpose of this study was to examine the association of sex, MBFR, and mortality in consecutive patients with suspected or known coronary artery disease undergoing positron emission tomography myocardial perfusion imaging.MethodsUnique consecutive patients undergoing rubidium (Rb)-82 rest/stress positron emission tomography myocardial perfusion imaging from 2010-2016 were followed for a median of 3.2 years. Multivariable Cox models were built to describe the interaction of sex and MBFR on all-cause and cardiac death for the overall population and stratified by extent of calcified atherosclerosis (none: coronary artery calcium score = 0, subclinical: coronary artery calcium >0, clinical: prior myocardial infarction/percutaneous coronary intervention) and abnormal perfusion (no significant obstructive disease: summed stress score = 0, 1%-9.9%, and ≥10%) at baseline.ResultsAmong 12,594 patients, 52.8% were women. Compared with men, women had a lower prevalence of known coronary artery disease (16.5% vs 29.5%; P < 0.001) and were less likely to undergo revascularization after myocardial perfusion imaging (4.9% vs 9.7%; P < 0.001), but were more likely to have a reduced MBFR of <2 (56.2% vs 50.6%; P < 0.001). There were 1,699 (13.5%) all-cause and 490 (3.9%) cardiac deaths. In fully adjusted Cox models, reduced MBFR was independently associated with higher risk of death (HR per 0.1-U decrease: 1.09 [95% CI: 1.08-1.10]; P < 0.001), but female sex was not (HR: 0.95 [95% CI: 0.85-1.05]; P = 0.27). There was no significant interaction between sex and MBFR on death (P = 0.22) and cardiac death (P = 0.35) overall or in subgroups of patients with clinical, subclinical, and no atherosclerosis or across categories of perfusion abnormality at baseline.ConclusionsThe association between reduced MBFR and higher risk of all-cause and cardiac death did not differ by sex, regardless of extent of coexisting atherosclerosis or perfusion abnormality.     

Coronary Atherosclerosis,Cardiac Troponin,and Interleukin-6 in Patients With Chest Pain: The PROMISE Trial Results

BackgroundIncreased inflammation and myocardial injury can be observed in the absence of myocardial infarction or obstructive coronary artery disease (CAD).ObjectivesThe authors determined whether biomarkers of inflammation and myocardial injury—interleukin (IL)-6 and high-sensitivity cardiac troponin (hs-cTn)—were associated with the presence and extent of CAD and were independent predictors of major adverse cardiovascular events (MACEs) in stable chest pain.MethodsUsing participants from the PROMISE trial, the authors measured hs-cTn I and IL-6 concentrations and analyzed computed tomography angiography (CTA) images in the core laboratory for CAD characteristics: significant stenosis (≥70%), high-risk plaque (HRP), Coronary Artery Disease Reporting and Data System (CAD-RADS) categories, segment involvement score (SIS), and coronary artery calcium (CAC) score. The primary endpoint was a composite MACE (death, myocardial infarction, or unstable angina).ResultsThe authors included 1,796 participants (age 60.2 ± 8.0 years; 47.5% men, median follow-up 25 months). In multivariable linear regression adjusted for atherosclerotic cardiovascular disease (ASCVD) risk, hs-cTn was associated with HRP, stenosis, CAD-RADS, and SIS. IL-6 was only associated with stenosis and CAD-RADS. hs-cTn above median (1.5 ng/L) was associated with MACEs in univariable analysis (HR: 2.1 [95% CI: 1.3-3.6]; P = 0.006), but not in multivariable analysis adjusted for ASCVD and CAD. IL-6 above median (1.8 ng/L) was associated with MACEs in multivariable analysis adjusted for ASCVD and HRP (HR: 1.9 [95% CI: 1.1-3.3]; P = 0.03), CAC (HR: 1.9 [95% CI: 1.0-3.4]; P = 0.04), and SIS (HR: 1.8 [95% CI: 1.0-3.2]; P = 0.04), but not for stenosis or CAD-RADS. In participants with nonobstructive CAD (stenosis 1%-69%), the presence of both hs-cTn and IL-6 above median was strongly associated with MACEs (HR: 2.5-2.7 after adjustment for CAD characteristics).ConclusionsConcentrations of hs-cTn and IL-6 were associated with CAD characteristics and MACEs, indicating that myocardial injury and inflammation may each contribute to pathways in CAD pathophysiology. This association was most pronounced among participants with nonobstructive CAD representing an opportunity to tailor treatment in this at-risk group. (PROspective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550)     

Ischemic Burden Reduction and Long-Term Clinical Outcomes After Chronic Total Occlusion Percutaneous Coronary Intervention

ObjectivesThe authors sought to evaluate the impact of ischemic burden reduction after chronic total occlusion (CTO) percutaneous coronary intervention (PCI) on long-term prognosis and cardiac symptom relief.BackgroundThe clinical benefit of CTO PCI is questioned.MethodsIn a high-volume CTO PCI center, 212 patients prospectively underwent quantitative [¹⁵O]H₂O positron emission tomography perfusion imaging before and three months after successful CTO PCI between 2013-2019. Perfusion defects (PD) (in segments) and hyperemic myocardial blood flow (hMBF) (in ml · min^?1 · g^?1) allocated to CTO areas were related to prognostic outcomes using unadjusted (Kaplan-Meier curves, log-rank test) and risk-adjusted (multivariable Cox regression) analyses. The prognostic endpoint was a composite of all-cause death and nonfatal myocardial infarction.ResultsAfter a median [interquartile range] of 2.8 years [1.8 to 4.3 years], event-free survival was superior in patients with ≥3 versus <3 segment PD reduction (p < 0.01; risk-adjusted p = 0.04; hazard ratio [HR]: 0.34 [95% confidence interval (CI): 0.13 to 0.93]) and with hMBF increase above (Δ≥1.11 ml · min^?1 · g^?1) versus below the population median (p < 0.01; risk-adjusted p < 0.01; HR: 0.16 [95% CI: 0.05 to 0.54]) after CTO PCI. Furthermore, event-free survival was superior in patients without versus any residual PD (p < 0.01; risk-adjusted p = 0.02; HR: 0.22 [95% CI: 0.06 to 0.76]) or with a residual hMBF level >2.3 versus ≤2.3 ml · min^?1 · g^?1 (p < 0.01; risk-adjusted p = 0.03; HR: 0.25 [95% CI: 0.07 to 0.91]) at follow-up positron emission tomography. Patients with residual hMBF >2.3 ml · min^?1 · g^?1 were more frequently free of angina and dyspnea on exertion at long-term follow-up (p = 0.04).ConclusionsPatients with extensive ischemic burden reduction and no residual ischemia after CTO PCI had lower rates of all-cause death and nonfatal myocardial infarction. Long-term cardiac symptom relief was associated with normalization of hMBF levels after CTO PCI.     

Lung Ultrasound and Pulmonary Congestion During Stress Echocardiography

ObjectivesThe purpose of this study was to assess the functional and prognostic correlates of B-lines during stress echocardiography (SE).BackgroundB-profile detected by lung ultrasound (LUS) is a sign of pulmonary congestion during SE.MethodsThe authors prospectively performed transthoracic echocardiography (TTE) and LUS in 2,145 patients referred for exercise (n = 1,012), vasodilator (n = 1,054), or dobutamine (n = 79) SE in 11 certified centers. B-lines were evaluated in a 4-site simplified scan (each site scored from 0: A-lines to 10: white lung for coalescing B-lines). During stress the following were also analyzed: stress-induced new regional wall motion abnormalities in 2 contiguous segments; reduced left ventricular contractile reserve (peak/rest based on force, ≤2.0 for exercise and dobutamine, ≤1.1 for vasodilators); and abnormal coronary flow velocity reserve ≤2.0, assessed by pulsed-wave Doppler sampling in left anterior descending coronary artery and abnormal heart rate reserve (peak/rest heart rate) ≤1.80 for exercise and dobutamine (≤1.22 for vasodilators). All patients completed follow-up.ResultsAccording to B-lines at peak stress patients were divided into 4 different groups: group I, absence of stress B-lines (score: 0 to 1; n = 1,389; 64.7%); group II, mild B-lines (score: 2 to 4; n = 428; 20%); group III, moderate B-lines (score: 5 to 9; n = 209; 9.7%) and group IV, severe B-lines (score: ≥10; n = 119; 5.4%). During median follow-up of 15.2 months (interquartile range: 12 to 20 months) there were 38 deaths and 28 nonfatal myocardial infarctions in 64 patients. At multivariable analysis, severe stress B-lines (hazard ratio [HR]: 3.544; 95% confidence interval [CI]: 1.466 to 8.687; p = 0.006), abnormal heart rate reserve (HR: 2.276; 95% CI: 1.215 to 4.262; p = 0.010), abnormal coronary flow velocity reserve (HR: 2.178; 95% CI: 1.059 to 4.479; p = 0.034), and age (HR: 1.031; 95% CI: 1.002 to 1.062; p = 0.037) were independent predictors of death and nonfatal myocardial infarction.ConclusionsSevere stress B-lines predict death and nonfatal myocardial infarction. (Stress Echo 2020–The International Stress Echo Study [SE2020]; NCT03049995)     

Prognostic Value of Stress CMR Perfusion Imaging in Patients With Reduced Left Ventricular Function

ObjectivesThe aim of this study was to investigate the prognostic value of stress cardiac magnetic resonance imaging (CMR) in patients with reduced left ventricular (LV) systolic function.BackgroundPatients with ischemic cardiomyopathy are at risk from both myocardial ischemia and heart failure. Invasive testing is often used as the first-line investigation, and there is limited evidence as to whether stress testing can effectively provide risk stratification.MethodsIn this substudy of a multicenter registry from 13 U.S. centers, patients with reduced LV ejection fraction (<50%), referred for stress CMR for suspected myocardial ischemia, were included. The primary outcome was cardiovascular death or nonfatal myocardial infarction. The secondary outcome was a composite of cardiovascular death, nonfatal myocardial infarction, hospitalization for unstable angina or congestive heart failure, and unplanned late coronary artery bypass graft surgery.ResultsAmong 582 patients (mean age 62 ± 12 years, 34% women), 40% had a history of congestive heart failure, and the median LV ejection fraction was 39% (interquartile range: 28% to 45%). At median follow-up of 5.0 years, 97 patients had experienced the primary outcome, and 182 patients had experienced the secondary outcome. Patients with no CMR evidence of ischemia or late gadolinium enhancement (LGE) experienced an annual primary outcome event rate of 1.1%. The presence of ischemia, LGE, or both was associated with higher event rates. In a multivariate model adjusted for clinical covariates, ischemia and LGE were independent predictors of the primary (hazard ratio [HR]: 2.63; 95% confidence interval [CI]: 1.68 to 4.14; p < 0.001; and HR: 1.86; 95% CI: 1.05 to 3.29; p = 0.03) and secondary (HR: 2.14; 95% CI: 1.55 to 2.95; p < 0.001; and HR 1.70; 95% CI: 1.16 to 2.49; p = 0.007) outcomes. The addition of ischemia and LGE led to improved model discrimination for the primary outcome (change in C statistic from 0.715 to 0.765; p = 0.02). The presence and extent of ischemia were associated with higher rates of use of downstream coronary angiography, revascularization, and cost of care spent on ischemia testing.ConclusionsStress CMR was effective in risk-stratifying patients with reduced LV ejection fractions. (Stress CMR Perfusion Imaging in the United States [SPINS] Study; NCT03192891)     

Sex-Related Differences in Thrombus Burden in STEMI Patients Undergoing Primary Percutaneous Coronary Intervention

BackgroundWomen have a worse prognosis after ST-segment elevation myocardial infarction (STEMI) than men. The prognostic role of thrombus burden (TB) in influencing the sex-related differences in clinical outcomes after STEMI has not been clearly investigated.ObjectivesThe aim of this study was to assess the sex-related differences in TB and its clinical implications in patients with STEMI.MethodsIndividual patient data from the 3 major randomized clinical trials of manual thrombus aspiration were analyzed, encompassing a total of 19,047 patients with STEMI, of whom 13,885 (76.1%) were men and 4,371 (23.9%) were women. The primary outcome of interest was 1-year cardiovascular (CV) death. The secondary outcomes of interest were recurrent myocardial infarction, heart failure, all-cause mortality, stroke, stent thrombosis (ST), and target vessel revascularization at 1 year.ResultsPatients with high TB (HTB) had worse 1-year outcomes compared with those presenting with low TB (adjusted HR for CV death: 1.52; 95% CI: 1.10-2.12; P = 0.01). In unadjusted analyses, female sex was associated with an increased risk for 1-year CV death regardless of TB. After adjustment, the risk for 1-year CV death was higher only in women with HTB (HR: 1.23; 95% CI: 1.18-1.28; P < 0.001), who also had an increased risk for all-cause death and ST than men.ConclusionsIn patients with STEMI, angiographic evidence of HTB negatively affected prognosis. Among patients with HTB, women had an excess risk for ST, CV, and all-cause mortality than men. Further investigations are warranted to better understand the pathophysiological mechanisms leading to excess mortality in women with STEMI and HTB.     

Association of Tube Voltage With Plaque Composition on Coronary CT Angiography: Results From PARADIGM Registry

ObjectivesThis study sought to investigate the impact of low tube voltage scanning heterogeneity of coronary luminal attenuation on plaque quantification and characterization with coronary computed tomography angiography (CCTA).BackgroundThe impact of low tube voltage and coronary luminal attenuation on quantitative coronary plaque remains uncertain.MethodsA total of 1,236 consecutive patients (age: 60 ± 9 years; 41% female) who underwent serial CCTA at an interval of ≥2 years were included from an international registry. Patients with prior revascularization or nonanalyzable coronary CTAs were excluded. Total coronary plaque volume was assessed and subclassified based on specific Hounsfield unit (HU) threshold: necrotic core, fibrofatty plaque, and fibrous plaque and dense calcium. Luminal attenuation was measured in the aorta.ResultsWith increasing luminal HU (<350, 350-500, and >500 HU), percent calcified plaque was increased (16%, 27%, and 40% in the median; P < 0.001), and fibrofatty plaque (26%, 13%, and 4%; P < 0.001) and necrotic core (1.6%, 0.3%, and 0.0%; P < 0.001) were decreased. Higher tube voltage scanning (80, 100, and 120 kV) resulted in decreasing luminal attenuation (689 ± 135, 497 ± 89, and 391 ± 73 HU; P < 0.001) and calcified plaque volume (59%, 34%, and 23%; P < 0.001) and increased fibrofatty plaque (3%, 9%, and 18%; P < 0.001) and necrotic core (0.2%, 0.1%, and 0.6%; P < 0.001). Mediation analysis showed that the impact of 100 kV on plaque composition, compared with 120 kV, was primarily caused by an indirect effect through blood pool attenuation. Tube voltage scanning of 80 kV maintained a direct effect on fibrofatty plaque and necrotic core in addition to an indirect effect through the luminal attenuation.ConclusionsLow tube voltage usage affected plaque morphology, mainly through an increase in luminal HU with a resultant increase in calcified plaque and a reduction in fibrofatty and necrotic core. These findings should be considered as CCTA-based plaque measures are being used to guide medical management and, in particular, when being used as a measure of treatment response. (Progression of Atherosclerotic Plaque Determined by Computed Tomographic Angiography Imaging [PARADIGM]; NCT02803411)     

High triglyceride-glucose index is associated with adverse cardiovascular outcomes in patients with acute myocardial infarction

Background and aimsTriglyceride glucose (TyG) index is considered a new surrogate marker of insulin resistance that associated with the development of vascular disease. The aim of this study was to evaluate the prognostic value of TyG index in patients with acute myocardial infarction (AMI).Methods and resultsA total of 3181 patients with AMI were included in the analysis. Patients were stratified into 2 groups according to their TyG index levels: the TyG index <8.88 group and the TyG index ≥8.88 group. The incidence of major adverse cardiovascular events (MACEs) during a median of 33.3-month follow-up were recorded. Multivariable Cox regression models revealed that the TyG index was positively associated with all-cause death [HR (95% CI): 1.51 (1.10,2.06), p = 0.010], cardiac death [HR (95% CI): 1.68 (1.19,2.38), p = 0.004], revascularization [HR (95% CI): 1.50 (1.16,1.94), p = 0.002], cardiac rehospitalization [HR (95% CI): 1.25 (1.05,1.49), p = 0.012], and composite MACEs [HR (95% CI): 1.19 (1.01,1.41), p = 0.046] in patients with AMI. The independent predictive effect of TyG index on composite MACEs was mainly reflected in the subgroups of male gender and smoker. The area under the curve (AUC) of the TyG index predicting the occurrence of MACEs in AMI patients was 0.602 [95% CI 0.580,0.623; p < 0.001].ConclusionHigh TyG index levels appeared to be associated with an increased risk of MACEs in patients with AMI. The TyG index might be a valid predictor of cardiovascular outcomes of patients with AMI.Trial registrationRetrospectively registered.     

Direct Risk Assessment From Myocardial Perfusion Imaging Using Explainable Deep Learning

BackgroundMyocardial perfusion imaging (MPI) is frequently used to provide risk stratification, but methods to improve the accuracy of these predictions are needed.ObjectivesThe authors developed an explainable deep learning (DL) model (HARD MACE [major adverse cardiac events]-DL) for the prediction of death or nonfatal myocardial infarction (MI) and validated its performance in large internal and external testing groups.MethodsPatients undergoing single-photon emission computed tomography MPI were included, with 20,401 patients in the training and internal testing group (5 sites) and 9,019 in the external testing group (2 different sites). HARD MACE-DL uses myocardial perfusion, motion, thickening, and phase polar maps combined with age, sex, and cardiac volumes. The primary outcome was all-cause mortality or nonfatal MI. Prognostic accuracy was evaluated using area under the receiver-operating characteristic curve (AUC).ResultsDuring internal testing, patients with normal perfusion and elevated HARD MACE-DL risk were at higher risk than patients with abnormal perfusion and low HARD MACE-DL risk (annualized event rate, 2.9% vs 1.2%; P < 0.001). Patients in the highest quartile of HARD MACE-DL score had an annual rate of death or MI (4.8%) 10-fold higher than patients in the lowest quartile (0.48% per year). In external testing, the AUC for HARD MACE-DL (0.73; 95% CI: 0.71-0.75) was higher than a logistic regression model (AUC: 0.70), stress total perfusion deficit (TPD) (AUC: 0.65), and ischemic TPD (AUC: 0.63; all P < 0.01). Calibration, a measure of how well predicted risk matches actual risk, was excellent in both groups (Brier score, 0.079 for internal and 0.070 for external).ConclusionsThe DL model predicts death or MI directly from MPI, by estimating patient-level risk with good calibration and improved accuracy compared with traditional quantitative approaches. The model incorporates mechanisms to explain to the physician which image regions contribute to the adverse event prediction.     

Prognostic Value of Computed Tomography-Derived Fractional Flow Reserve Comparison With Myocardial Perfusion Imaging

ObjectivesThe aim of this study was to compare the incremental prognostic value of coronary computed tomography (CT) angiography (CCTA)-derived machine learning fractional flow reserve CT (ML-FFRct) versus that of ischemia detected on single-photon emission-computed tomography (SPECT) myocardial perfusion imaging (MPI) on incident cardiovascular outcomes.BackgroundSPECT MPI and ML-FFRct are noninvasive tools that can assess the hemodynamic significance of coronary atherosclerotic disease.MethodsWe studied a retrospective cohort of consecutive patients who underwent clinically indicated CCTA and SPECT MPI. ML-FFRct was computed using a ML prototype. The primary outcome was all-cause mortality and nonfatal myocardial infarction (D/MI), and the secondary outcome was D/MI and unplanned revascularization, percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) occurring more than 90 days postimaging. Multiple nested multivariate cox regression was used to model a scenario wherein an initial anatomical assessment was followed by a functional assessment.ResultsA total of 471 patients (mean age: 64 ± 13 year; 53% males) were included. Comorbidities were prevalent (78% hypertension, 66% diabetes, 81% dyslipidemia). ML-FFRct was <0.8 in at least 1 proximal/midsegment was present in 41.6% of patients, and ischemia on MPI was present in 13.8%. After a median follow-up of 18 months, 7% of patients (n = 33) experienced D/MI. On multivariate Cox proportional analysis, the presence of ischemia on MPI but not ML-FFRct significantly predicted D/MI (HR: 2.3; 95% CI: 1.0-5.0; P = 0.047; or HR: 0.7; 95% CI: 0.3-1.4; P = 0.306 respectively) when added to CCTA obstructive stenosis. Furthermore, the model with SPECT ischemia had higher global chi-square result and significantly improved reclassification. Results were similar using the secondary outcome and on several sensitivity analyses.ConclusionsIn a high-risk patient cohort, SPECT MPI but not ML-FFRct adds independent and incremental prognostic information to CCTA-based anatomical assessment and clinical risk factors in predicting incident outcomes.     

Sex-Specific Stress Perfusion Cardiac Magnetic Resonance Imaging in Suspected Ischemic Heart Disease: Insights From SPINS Retrospective Registry

BackgroundCardiovascular disease (CVD) remains the leading cause of mortality in women, but current noninvasive cardiac imaging techniques have sex-specific limitations.ObjectivesIn this study, the authors sought to investigate the effect of sex on the prognostic utility and downstream invasive revascularization and costs of stress perfusion cardiac magnetic resonance (CMR) for suspected CVD.MethodsSex-specific prognostic performance was evaluated in a 2,349-patient multicenter SPINS (Stress CMR Perfusion Imaging in the United States [SPINS] Study) Registry. The primary outcome measure was a composite of cardiovascular death and nonfatal myocardial infarction; secondary outcomes were hospitalization for unstable angina or heart failure, and late unplanned coronary artery bypass grafting.ResultsSPINS included 1,104 women (47% of cohort); women had higher prevalence of chest pain (62% vs 50%; P < 0.0001) but lower use of medical therapies. At the 5.4-year median follow-up, women with normal stress CMR had a low annualized rate of primary composite outcome similar to men (0.54%/y vs 0.75%/y, respectively; P = NS). In contrast, women with abnormal CMR were at higher risk for both primary (3.74%/y vs 0.54%/y; P < 0.0001) and secondary (9.8%/y vs 1.6%/y; P < 0.0001) outcomes compared with women with normal CMR. Abnormal stress CMR was an independent predictor for the primary (HR: 2.64 [95% CI: 1.20-5.90]; P = 0.02) and secondary (HR: 2.09 [95% CI: 1.43-3.08]; P < 0.0001) outcome measures. There was no effect modification for sex. Women had lower rates of invasive coronary angiography (3.6% vs 7.3%; P = 0.0001) and downstream costs ($114 vs $171; P = 0.001) at 90 days following CMR. There was no effect of sex on diagnostic image quality.ConclusionsStress CMR demonstrated excellent prognostic performance with lower rates of invasive coronary angiography referral in women. Stress CMR should be considered as a first-line noninvasive imaging tool for the evaluation of women. (Stress CMR Perfusion Imaging in the United States [SPINS] Study [SPINS]; NCT03192891)     

Global Circumferential and Radial Strain Among Patients With Immune Checkpoint Inhibitor Myocarditis

BackgroundGlobal circumferential strain (GCS) and global radial strain (GRS) are reduced with cytotoxic chemotherapy. There are limited data on the effect of immune checkpoint inhibitor (ICI) myocarditis on GCS and GRS.ObjectivesThis study aimed to detail the role of GCS and GRS in ICI myocarditis.MethodsIn this retrospective study, GCS and GRS from 75 cases of patients with ICI myocarditis and 50 ICI-treated patients without myocarditis (controls) were compared. Pre-ICI GCS and GRS were available for 12 cases and 50 controls. Measurements were performed in a core laboratory blinded to group and time. Major adverse cardiovascular events (MACEs) were defined as a composite of cardiogenic shock, cardiac arrest, complete heart block, and cardiac death.ResultsCases and controls were similar in age (66 ± 15 years vs 63 ± 12 years; P = 0.20), sex (male: 73% vs 61%; P = 0.20) and cancer type (P = 0.08). Pre-ICI GCS and GRS were also similar (GCS: 22.6% ± 3.4% vs 23.5% ± 3.8%; P = 0.14; GRS: 45.5% ± 6.2% vs 43.6% ± 8.8%; P = 0.24). Overall, 56% (n = 42) of patients with myocarditis presented with preserved left ventricular ejection fraction (LVEF). GCS and GRS were lower in myocarditis compared with on-ICI controls (GCS: 17.5% ± 4.2% vs 23.6% ± 3.0%; P < 0.001; GRS: 28.6% ± 6.7% vs 47.0% ± 7.4%; P < 0.001). Over a median follow-up of 30 days, 28 cardiovascular events occurred. A GCS (HR: 4.9 [95% CI: 1.6-15.0]; P = 0.005) and GRS (HR: 3.9 [95% CI: 1.4-10.8]; P = 0.008) below the median was associated with an increased event rate. In receiver-operating characteristic (ROC) curves, GCS (AUC: 0.80 [95% CI: 0.70-0.91]) and GRS (AUC: 0.76 [95% CI: 0.64-0.88]) showed better performance than cardiac troponin T (cTnT) (AUC: 0.70 [95% CI: 0.58-0.82]), LVEF (AUC: 0.69 [95% CI: 0.56-0.81]), and age (AUC: 0.54 [95% CI: 0.40-0.68]). Net reclassification index and integrated discrimination improvement demonstrated incremental prognostic utility of GRS over LVEF (P = 0.04) and GCS over cTnT (P = 0.002).ConclusionsGCS and GRS are lower in ICI myocarditis, and the magnitude of reduction has prognostic significance.