Comparison of oral anticoagulation by vitamin-K antagonists and non-vitamin-K antagonists for treatment of leaflet thickening after transcatheter aortic valve implantation (TAVI)

INTRODUCTION

Hypoattenuated leaflet thickening (HALT), as identified by CT imaging, is not infrequent after transcatheter aortic valve implantation (TAVI). The best choice of oral anticoagulation is unknown. We compared the effectiveness of Direct Oral AntiCoagulants (DOAC) and Vitamin-K Antagonists (VKA) to resolve HALT in patients with serial CT aquisitions.

METHODS

A total of 46 consecutive TAVI patients in whom anticoagulation had been initiated because of HALT and who underwent follow-up CT were identified. Indication and type of anticoagulation was according to physician discretion. Patients on DOAC were compared to VKA therapy regarding resolution of HALT.

RESULTS

Mean age of the 46 patients was 80 ± 6 years (59% men), and the mean duration of anticoagulation was 156 days. Overall, 41 patients (89%) showed resolution of HALT with anticoagulation therapy, whereas HALT persisted in 5 patients (11%). Resolution of HALT was seen in 26 out of 30 (87%) patients receiving VKA and in 15 out of 16 (94%) patients receiving DOAC, respectively. Groups did not differ regarding age, cardiovascular risk factors, TAVI prosthesis type and size or duration of anticoagulation (all p > 0.05).

CONCLUSION

Anticoagulation therapy resolves leaflet thickening after TAVI in most patients. Non-Vitamin-K antagonists seem to be an effective alternative to Vitamin-K antagonists. This finding needs to be confirmed in larger prospective trials.

Risk factors for cardiovascular disease among individuals with hepatic steatosis

Cardiovascular disease (CVD) is the leading cause of mortality in adults with hepatic steatosis (HS). However, risk factors for CVD in HS are unknown. We aimed to identify factors associated with coronary artery disease (CAD) and incident major adverse cardiovascular events (MACE) in individuals with HS. We performed a nested cohort study of adults with HS detected on coronary computed tomography in the PROspective Multicenter Imaging Study for Evaluation of chest pain (PROMISE) trial. Obstructive CAD was defined as ≥50% coronary stenosis. MACE included hospitalization for unstable angina, nonfatal myocardial infarction, or all-cause death. Multivariate modeling, adjusted for age, sex, atherosclerotic CVD (ASCVD) risk score and body mass index, identified factors associated with obstructive CAD. Cox regression, adjusted for ASCVD risk score, determined the predictors of MACE. A total of 959 of 3,756 (mean age 59.4 years, 55.0% men) had HS. Obstructive CAD was present in 15.2% (145 of 959). Male sex (adjusted odds ratio [aOR] = 1.83, 95% confidence interval [CI] 1.18-1.2.84; p = 0.007), ASCVD risk score (aOR = 1.05, 95% CI 1.03-1.07; p < 0.001), and n-terminal pro-b-type natriuretic peptide (NT-proBNP; aOR = 1.90, 95% CI 1.38-2.62; p < 0.001) were independently associated with obstructive CAD. In the 25-months median follow-up, MACE occurred in 4.4% (42 of 959). Sedentary lifestyle (adjusted hazard ratio [aHR] = 2.53, 95% CI 1.27-5.03; p = 0.008) and NT-proBNP (aOR = 1.50, 95% CI 1.01-2.25; p = 0.046) independently predicted MACE. Furthermore, the risk of MACE increased by 3% for every 1% increase in ASCVD risk score (aHR = 1.03, 95% CI 1.01-1.05; p = 0.02). Conclusion: In individuals with HS, male sex, NT-pro-BNP, and ASCVD risk score are associated with obstructive CAD. Furthermore, ASCVD, NT-proBNP, and sedentary lifestyle are independent predictors of MACE. These factors, with further validation, may help risk-stratify adults with HS for incident CAD and MACE.

Differences in Cardiovascular Risk, Coronary Artery Disease, and Cardiac Events Between Black and White Individuals Enrolled in the PROMISE Trial

IMPORTANCE

Race and ethnicity have been studied as risk factors in cardiovascular disease. How risk factors, epicardial coronary artery disease, and cardiac events differ between Black and White individuals undergoing noninvasive testing for coronary artery disease is not known.

OBJECTIVE

To assess differences in cardiovascular risk burden, coronary plaque, and major adverse cardiac events between Black and White individuals assigned to receive coronary computed tomography angiography (CCTA) or functional testing for stable chest pain.

DESIGN, SETTING, AND PARTICIPANTS

A nested observational cohort study within the PROMISE trial was conducted at 193 outpatient sites in North America. A total of 1071 non-Hispanic Black (hereafter Black) and 7693 non-Hispanic White (hereafter White) participants with stable chest pain undergoing noninvasive cardiovascular testing were included. This analysis was conducted from February 13, 2015, to November 2, 2021.

MAIN OUTCOMES AND MEASURES

The primary end point was the composite of death, myocardial infarction, or hospitalization for unstable angina over a median follow-up of 24.4 months.

RESULTS

Among 1071 Black individuals (12.2%) (women, 646 [60.3%]; mean [SD] age, 59 [8] years) and 7693 White individuals (87.8%) (women, 4029 [52.4%]; mean [SD] age, 61.1 [8.4] years), Black participants had a higher cardiovascular risk burden (more hypertension and diabetes), yet there was a similarly low major adverse cardiovascular events rate over a median 2-year follow-up (32 [3.0%] vs 243 [3.2%]; P = .84). Sensitivity analyses restricted to the 79.8% (6993 of 8764) individuals with a normal or mildly abnormal noninvasive testing result and the 54.3% (4559 of 8396) not receiving statin therapy yielded similar findings. In comparison of Black and White individuals in the CCTA group (n = 3323), significant coronary stenosis (hazard ratio [HR], 7.21; 95% CI, 1.94-26.76 vs HR, 4.30; 95% CI, 2.62-7.04) and high-risk plaque (HR, 3.47; 95% CI, 1.00-12.06 vs HR, 2.21; 95% CI, 1.37-3.57) were associated with major adverse cardiovascular events in both Black and White patients. However, with respect to epicardial coronary artery disease burden, Black individuals had a less-prevalent coronary artery calcium score greater than 0 (45.1% vs 63.2%; P < .001), coronary stenosis greater than or equal to 50% (32 [8.7%] vs 430 [14.6%]; P = .001), and high-risk plaque (139 [37.6%] vs 1547 [52.4%]; P < .001).

CONCLUSIONS AND RELEVANCE

The findings of this study suggest that, despite a greater cardiovascular risk burden in Black persons, rates of coronary artery calcium, stenosis, and high-risk plaque observed via CCTA were lower in Black persons than White persons. This result suggests differences in cardiovascular risk burden and coronary plaque in Black and White individuals with stable chest pain.

Influence of reconstruction kernels on the accuracy of CT-derived fractional flow reserve

OBJECTIVES

We evaluated the influence of image reconstruction kernels on the diagnostic accuracy of CT-derived fractional flow reserve (FFR_CT) compared to invasive FFR in patients with coronary artery disease.

METHODS

Sixty-nine patients, in whom coronary CT angiography was performed and who were further referred for invasive coronary angiography with FFR measurement via pressure wire, were retrospectively included. CT data sets were acquired using a third-generation dual-source CT system and rendered with medium smooth (Bv40) and sharp (Bv49) reconstruction kernels. FFR_CT was calculated on-site using prototype software. Coronary stenoses with invasive FFR ≤ 0.80 were classified as significant. Agreement between FFR_CT and invasive FFR was determined for both reconstruction kernels.

RESULTS

One hundred analyzed vessels in 69 patients were included. Twenty-five vessels were significantly stenosed according to invasive FFR. Using a sharp reconstruction kernel for FFR_CT resulted in a significantly higher correlation with invasive FFR (r = 0.74, p < 0.01 vs. r = 0.58, p < 0.01; p = 0.04) and a higher AUC in ROC curve analysis to correctly identify/exclude significant stenosis (AUC = 0.92 vs. AUC = 0.82 for sharp vs. medium smooth kernel, respectively, p = 0.02). A FFR_CT value of ≤ 0.8 using a sharp reconstruction kernel showed a sensitivity of 88% and a specificity of 92% for detecting ischemia-causing lesions, resulting in a diagnostic accuracy of 91%. The medium smooth reconstruction kernel performed worse (sensitivity 60%, specificity 89%, accuracy 82%).

CONCLUSION

Compared to invasively measured FFR, FFR_CT using a sharp image reconstruction kernel shows higher diagnostic accuracy for detecting lesions causing ischemia, potentially altering decision-making in a clinical setting.

KEY POINTS

• Image reconstruction parameters influence the diagnostic accuracy of simulated fractional flow reserve derived from coronary computed tomography angiography. • Using a sharp kernel image reconstruction algorithm delivers higher diagnostic accuracy compared to medium smooth kernel image reconstruction (gold standard invasive fractional flow reserve).

Risk Stratification With the Use of Coronary Computed Tomographic Angiography in Patients With Nonobstructive Coronary Artery Disease

OBJECTIVES

The purpose of this study was to develop a risk prediction model for patients with nonobstructive CAD.

BACKGROUND

Among stable chest pain patients, most cardiovascular (CV) events occur in those with nonobstructive coronary artery disease (CAD). Thus, developing tailored risk prediction approaches in this group of patients, including CV risk factors and CAD characteristics, is needed.

METHODS

In PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) computed tomographic angiography patients, a core laboratory assessed prevalence of CAD (nonobstructive 1% to 49% left main or 1% to 69% stenosis any coronary artery), degree of stenosis (minimal: 1% to 29%; mild: 30% to 49%; or moderate: 50% to 69%), high-risk plaque (HRP) features (positive remodeling, low-attenuation plaque, and napkin-ring sign), segment involvement score (SIS), and coronary artery calcium (CAC). The primary end point was an adjudicated composite of unstable angina pectoris, nonfatal myocardial infarction, and death. Cox regression analysis determined independent predictors in nonobstructive CAD.

RESULTS

Of 2,890 patients (age 61.7 years, 46% women) with any CAD, 90.4% (n = 2,614) had nonobstructive CAD (mean age 61.6 yrs, 46% women, atherosclerotic cardiovascular disease [ASCVD] risk 16.2%). Composite events were independently predicted by ASCVD risk (hazard ratio [HR]: 1.03; p = 0.001), degree of stenosis (30% to 69%; HR: 1.91; p = 0.011), and presence of ≥2 HRP features (HR: 2.40; p = 0.008). Addition of ≥2 HRP features to: 1) ASCVD and CAC; 2) ASCVD and SIS; or 3) ASCVD and degree of stenosis resulted in a statistically significant improvement in model fit (p = 0.0036; p = 0.0176; and p = 0.0318; respectively). Patients with ASCVD ≥7.5%, any HRP, and mild/moderate stenosis had significantly higher event rates than those who did not meet those criteria (3.0% vs. 6.2%; p = 0.007).

CONCLUSIONS

Advanced coronary plaque features have incremental value over total plaque burden for the discrimination of clinical events in low-risk stable chest pain patients with nonobstructive CAD. This may be a first step to improve prevention in this cohort with the highest absolute risk for CV events.

Association of Hepatic Steatosis With Major Adverse Cardiovascular Events, Independent of Coronary Artery Disease

BACKGROUND & AIMS

Hepatic steatosis has been associated with increased risk of major adverse cardiovascular events (MACE) but it is not clear whether steatosis is independently associated with risk of MACE. We investigated whether steatosis is associated with risk of MACE independently of the presence and extent of baseline coronary artery disease, assessed by comprehensive contrast-enhanced computed tomography angiography (CTA).

METHODS

We conducted a nested cohort study of 3756 subjects (mean age, 60.6 years; 48.4% men) who underwent coronary CTA at 193 sites in North America, from July 2010 through September 2013, as part of the PROMISE study, which included noninvasive cardiovascular analyses of symptomatic outpatients without coronary artery disease. Independent core laboratory readers measured hepatic and splenic attenuation, using non-contrast computed tomography images to identify steatosis, and evaluated coronary plaques and stenosis in coronary CTA images. We collected data on participants' cardiovascular risk factors, presence of metabolic syndrome, and body mass index. The primary endpoint was an adjudicated composite of MACE (death, myocardial infarction, or unstable angina) during a median follow-up time of 25 months.

RESULTS

Among the 959 subjects who had steatosis (25.5% of the cohort), 42 had MACE (4.4%), whereas among the 2797 subjects without steatosis, 73 had MACE (2.6%) (hazard ratio [HR] for MACE in subjects with steatosis, 1.69; 95% CI, 1.16-2.48; P = .006 for MACE in subjects with vs without steatosis). This association remained after adjustment for atherosclerotic cardiovascular disease risk scores, significant stenosis, and metabolic syndrome (adjusted HR, 1.72; 95% CI, 1.16-2.54; P = .007) or obesity (adjusted HR, 1.75; 95% CI, 1.19-2.59; P = .005). Steatosis remained independently associated with MACE after adjustment for all CTA measures of plaques and stenosis.

CONCLUSIONS

Hepatic steatosis is associated with MACE independently of other cardiovascular risk factors or extent of coronary artery disease. Strategies to reduce steatosis might reduce risk of MACE. ClinicalTrials.gov no: NCT01174550.

Association of Metabolic Phenotypes With Coronary Artery Disease and Cardiovascular Events in Patients With Stable Chest Pain

OBJECTIVE

Obesity and metabolic syndrome are associated with major adverse cardiovascular events (MACE). However, whether distinct metabolic phenotypes differ in risk for coronary artery disease (CAD) and MACE is unknown. We sought to determine the association of distinct metabolic phenotypes with CAD and MACE.

RESEARCH DESIGN AND METHODS

We included patients from the Prospective Multicenter Imaging Study for Evaluation of Chest Pain (PROMISE) who underwent coronary computed tomography (CT) angiography. Obesity was defined as a BMI ≥30 kg/m² and metabolically healthy as less than or equal to one metabolic syndrome component except diabetes, distinguishing four metabolic phenotypes: metabolically healthy/unhealthy and nonobese/obese (MHN, MHO, MUN, and MUO). Differences in severe calcification (coronary artery calcification [CAC] ≥400), severe CAD (≥70% stenosis), high-risk plaque (HRP), and MACE were assessed using adjusted logistic and Cox regression models.

RESULTS

Of 4,381 patients (48.4% male, 60.5 ± 8.1 years of age), 49.4% were metabolically healthy (30.7% MHN and 18.7% MHO) and 50.6% unhealthy (22.3% MUN and 28.4% MUO). MHO had similar coronary CT findings as compared with MHN (severe CAC/CAD and HRP; P > 0.36 for all). Among metabolically unhealthy patients, those with obesity had similar CT findings as compared with nonobese (P > 0.10 for all). However, both MUN and MUO had unfavorable CAD characteristics as compared with MHN (P ≤ 0.017 for all). A total of 130 events occurred during follow-up (median 26 months). Compared with MHN, MUN (hazard ratio [HR] 1.61 [95% CI 1.02-2.53]) but not MHO (HR 1.06 [0.62-1.82]) or MUO (HR 1.06 [0.66-1.72]) had higher risk for MACE.

CONCLUSIONS

In patients with stable chest pain, four metabolic phenotypes exhibit distinctly different CAD characteristics and risk for MACE. Individuals who are metabolically unhealthy despite not being obese were at highest risk in our cohort.

Relationship between changes in pericoronary adipose tissue attenuation and coronary plaque burden quantified from coronary computed tomography angiography

AIMS

Increased attenuation of pericoronary adipose tissue (PCAT) around the proximal right coronary artery (RCA) from coronary computed tomography angiography (CTA) has been shown to be associated with coronary inflammation and improved prediction of cardiac death over plaque features. Our aim was to investigate whether PCAT CT attenuation is related to progression of coronary plaque burden.

METHODS AND RESULTS

We analysed CTA studies of 111 stable patients (age 59.2 ± 9.8 years, 77% male) who underwent sequential CTA (3.4 ± 1.6 years between scans) with identical acquisition protocols. Total plaque (TP), calcified plaque (CP), non-calcified plaque (NCP), and low-density non-calcified plaque (LD-NCP) volumes and corresponding burden (plaque volume × 100%/vessel volume) were quantified using semi-automated software. PCAT CT attenuation (HU) was measured around the proximal RCA, the most standardized method for PCAT analysis. Patients with an increase in NCP burden (n = 51) showed an increase in PCAT attenuation, whereas patients with a decrease in NCP burden (n = 60) showed a decrease {4.4 [95% confidence interval (CI) 2.6-6.2] vs. -2.78 (95% CI -4.6 to -1.0) HU, P < 0.0001}. Changes in PCAT attenuation correlated with changes in the burden of NCP (r = 0.55, P < 0.001) and LD-NCP (r = 0.24, P = 0.01); but not CP burden (P = 0.3). Increased baseline PCAT attenuation ≥-75 HU was independently associated with increase in NCP (odds ratio 3.07, 95% CI 1.4-7.0; P < 0.008) and TP burden on follow-up CTA.

CONCLUSION

PCAT attenuation measured from routine CTA is related to the progression of NCP and TP burden. This imaging biomarker may help to identify patients at increased risk of high-risk plaque progression and allow monitoring of beneficial changes from medical therapy.

Pretest probability for patients with suspected obstructive coronary artery disease: re-evaluating Diamond-Forrester for the contemporary era and clinical implications: insights from the PROMISE trial

AIMS

To update pretest probabilities (PTP) for obstructive coronary artery disease (CAD ≥ 50%) across age, sex, and clinical symptom strata, using coronary computed tomography angiography (CTA) in a large contemporary population of patients with stable chest pain referred to non-invasive testing.

METHODS AND RESULTS

We included patients enrolled in the Prospective Multicenter Imaging Study for Evaluation of Chest Pain (PROMISE) trial and randomized to CTA. Exclusively level III-certified readers, blinded to demographic and clinical data, assessed the prevalence of CAD ≥ 50% in a central core lab. After comparing the recent European Society of Cardiology-Diamond and Forrester PTP (ESC-DF) with the actual observed prevalence of CAD ≥ 50%, we created a new PTP set by replacing the ESC-DF PTP with the observed prevalence of CAD ≥ 50% across strata of age, sex, and type of angina. In 4415 patients (48.3% men; 60.5 ± 8.2 years; 78% atypical angina; 11% typical angina; 11% non-anginal chest pain), the observed prevalence of CAD ≥ 50% was 13.9%, only one-third of the average ESC-DF PTP (40.6; P < 0.001 for difference). The PTP in the new set ranged 2-48% and were consistently lower than the ESC-DF PTP across all age, sex, and angina type categories. Initially, 4284/4415 (97%) patients were classified as intermediate-probability by the ESC-DF (PTP 15-85%); using the PROMISE-PTP, 50.2% of these patients were reclassified to the low PTP category (PTP < 15%).

CONCLUSION

The ESC-DF PTP overestimate vastly the actual prevalence of CAD ≥ 50%. A new set of PTP, derived from results of non-invasive testing, may substantially reduce the need for non-invasive tests in stable chest pain.

Prognostic Value of Coronary CTA in Stable Chest Pain: CAD-RADS, CAC, and Cardiovascular Events in PROMISE

OBJECTIVES

The purpose of this study was to compare Coronary Artery Disease Reporting and Data System (CAD-RADS) to traditional stenosis categories and the coronary artery calcium score (CACS) for predicting cardiovascular events in patients with stable chest pain and suspected coronary artery disease (CAD).

BACKGROUND

The 2016 CAD-RADS has been established to standardize the reporting of CAD on coronary CT angiography (CTA).

METHODS

PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) trial participants' CTAs were assessed by a central CT core laboratory for CACS, traditional stenosis-based categories, and modified CAD-RADS grade including high-risk coronary plaque (HRP) features. Traditional stenosis categories and CAD-RADS grade were compared for the prediction of the composite endpoint of death, myocardial infarction, or hospitalization for unstable angina over a median follow-up of 25 months. Incremental prognostic value over traditional risk factors and CACS was assessed.

RESULTS

In 3,840 eligible patients (mean age: 60.4 ± 8.2 years; 49% men), 3.0% (115) experienced events. CAD-RADS (concordance statistic [C-statistic] 0.747) had significantly higher discriminatory value than traditional stenosis-based assessments (C-statistic 0.698 to 0.717; all p for comparison ≤0.001). With no plaque (CAD-RADS 0) as the baseline, the hazard ratio (HR) for an event increased from 2.43 (95% confidence interval [CI]: 1.16 to 5.08) for CAD-RADS 1 to 21.84 (95% CI: 8.63 to 55.26) for CAD-RADS 4b and 5. In stepwise nested models, CAD-RADS added incremental prognostic value beyond ASCVD risk score and CACS (C-statistic 0.776 vs. 0.682; p < 0.001), and added incremental value persisted in all CACS strata.

CONCLUSIONS

These data from a large representative contemporary cohort of patients undergoing coronary CTA for stable chest pain support the prognostic value of CAD-RADS as a standard reporting system for coronary CTA.

P3376Software-based automated CT analysis for planning TAVI-Procedures: Systematic validation against expert and novice human interpretation

Introduction

Cardiac computed tomography (CT) is an established modality for planning TAVI procedures.

We validated CT parameters measured by automated software analysis and by newly trained readers against expert readers.

Methods

Consecutive patients with symptomatic severe aortic valve stenosis referred for CT assessment of the aortic root prior to TAVI were included in this analysis. Measurements were performed manually by an expert reader, a newly trained reader as well as semi-automatically using a commercially available workstation. Manual measurements were performed as per clinical standard. For semi-automatic analysis, CT data sets were exported to a dedicated workstation with fully automated detection of the aortic annulus plane.

Results

Out of 159 consecutive patients, 146 patients were included in this analysis (83+10 years). The median annulus area for expert reader, newly trained reader and software measurement was 468 mm2, 511 mm2 and 513 mm2, respectively (p=0.28) whereas the mean annulus diameter showed a mean±SD of 25.6±2 mm, 25.5±2 mm and 25.6±2 mm, respectively, p=0.47. Agreement between expert and newly trained reader for annulus area was good with Bland-Altman analysis showing a systematic overestimation of the annulus area for the newly trained reader of 16 mm2 (95% limits of agreement 42 to −74 mm2) and for automatic software of 20 mm2 (95% limits of agreement 60 to −99 mm2). Assuming an annulus area-based recommendation for a balloon-expandable Sapien 3 prosthesis (23, 26 or 29 mm prosthesis), kappa statistics revealed moderate agreement between expert measurement, newly trained reader and software measurement (κ 0.60 for newly trained reader, κ 0.58 for software measurement, p<0.0001 for all). The time needed for annulus adjustment measurement for the newly trained reader compared to software measurement was 2±0.6 minutes vs. 1±0.5 minutes, respectively, p<0.0001). The software correctly identified the annulus plane without reader correction in 49% of cases and in 51% of cases manual correction of the cusp insertion point or annular tracing had to be performed. Agreement between expert predicted angulation and software predicted angulation was excellent in 55%, good in 29% vs. 31%, moderate in 11% vs. 6% and fair in 5% vs. 8% for LAO/RAO orientation, CAU/CRA orientation, respectively (assuming excellent agreement when difference: <5°, good agreement: 5–10°, moderate agreement: 10–15° and fair agreement: >15°).

Conclusion

Novice human interpretation manually and with semi-automatic assessment of the aortic root for planning TAVI procedures is feasible with good agreement with expert measurement for annulus dimensions and prediction of implantation angles, however with a trend for systematic overestimation of the annulus area. For semi-automatic assessment, reader correction of cusp insertion point and annular dimensions have to corrected for in 50% of cases

P6164High level of EPA is associated with lower perivascular coronary attenuation as measured by coronary CTA

Introduction

Pericoronary adipose tissue (PCAT) composition has been recently shown to be a potential novel marker of coronary inflammation with higher PCAT attenuation shown to indicate increased cardiac mortality. Polyunsaturated fatty acids (PUFAs), especially Omega-3 fatty acids (n3), are thought to alter inflammatory response and intake of high dose Eicosapentaenoic acid (EPA, C20_5 n3) was shown to decrease mortality, however exact pathophysiological mechanisms are unclear. Therefore, we sought to determine whether blood levels of PUFAs are associated with differences in pericoronary fat attenuation.

Methods

In 64 symptomatic patients with intermediate pretest-likelihood for coronary artery disease presenting with atypical angina, coronary CTA was performed. PCAT attenuation was measured in Hounsfield Units (HU) around the proximal 40mm of the right coronary artery (RCA) using semi-automated software. Erythrocyte membrane fatty acid composition (in percentage) was analyzed with a standardized analytical methodology, displaying a variety of fatty acids including n-3 fatty acids using gas chromatography.

Results

Patients were divided into two groups (each n=32) using the median PCAT attenuation of −78.1 Hounsfield units (HU), resulting in one group with low (−95.58 to −78.17 HU) and one with high (−78.06 to −62.92 HU) PCAT attenuation. Among both groups, no differences were seen in age, sex, BMI, traditional cardiovascular risk factors or the number of cardiovascular risk factors (all p>0.05). In univariate analysis, significantly higher values of EPA (1.00% [0.78; 1.26] vs. 0.78% [0.63; 0.99]; p=0.02) were seen in patients with lower PCAT attenuation. All other fatty acids showed no significant differences (all p>0.05). Moreover, a significant negative correlation was seen between PCAT attenuation and EPA (Pearson correlation coefficient −0.38; p=0.002), but not for age, sex, BMI or number of cardiovascular risk factors (all p>0.1). Multivariable linear regression analysis confirmed this association and showed a significant inverse association of EPA to PCAT attenuation (β=−0.31, p=0.017), independent of age, gender, BMI and number of CV risk factors (all p>0.1).

Conclusion

High levels of EPA are associated with lower PCAT attenuation on coronary CTA indicating different composition of pericoronary adipose tissue potentially caused by a lesser degree of coronary inflammation.

Use of High-Risk Coronary Atherosclerotic Plaque Detection for Risk Stratification of Patients With Stable Chest Pain: A Secondary Analysis of the PROMISE Randomized Clinical Trial

Importance

Coronary computed tomographic angiography (coronary CTA) can characterize coronary artery disease, including high-risk plaque. A noninvasive method of identifying high-risk plaque before major adverse cardiovascular events (MACE) could provide practice-changing optimizations in coronary artery disease care.

Objective

To determine whether high-risk plaque detected by coronary CTA was associated with incident MACE independently of significant stenosis (SS) and cardiovascular risk factors.

Design, Setting, and Participants

This prespecified nested observational cohort study was part of the Prospective Multicenter Imaging Study for Evaluation of Chest Pain (PROMISE) trial. All stable, symptomatic outpatients in this trial who required noninvasive cardiovascular testing and received coronary CTA were included and followed up for a median of 25 months.

Exposures

Core laboratory assessment of coronary CTA for SS and high-risk plaque (eg, positive remodeling, low computed tomographic attenuation, or napkin-ring sign).

Main Outcomes and Measures

The primary end point was an adjudicated composite of MACE (defined as death, myocardial infarction, or unstable angina).

Results

The study included 4415 patients, of whom 2296 (52%) were women, with a mean age of 60.5 years, a median atherosclerotic cardiovascular disease (ASCVD) risk score of 11, and a MACE rate of 3% (131 events). A total of 676 patients (15.3%) had high-risk plaques, and 276 (6.3%) had SS. The presence of high-risk plaque was associated with a higher MACE rate (6.4% vs 2.4%; hazard ratio, 2.73; 95% CI, 1.89-3.93). This association persisted after adjustment for ASCVD risk score and SS (adjusted hazard ratio [aHR], 1.72; 95% CI, 1.13-2.62). Adding high-risk plaque to the ASCVD risk score and SS assessment led to a significant continuous net reclassification improvement (0.34; 95% CI, 0.02-0.51). Presence of high-risk plaque increased MACE risk among patients with nonobstructive coronary artery disease relative to patients without high-risk plaque (aHR, 4.31 vs 2.64; 95% CI, 2.25-8.26 vs 1.49-4.69). There were no significant differences in MACE in patients with SS and high-risk plaque as opposed to those with SS but not high-risk plaque (aHR, 8.68 vs. 9.31; 95% CI, 4.25-17.73 vs 4.21-20.61). High-risk plaque was a stronger predictor of MACE in women (aHR, 2.41; 95% CI, 1.25-4.64) vs men (aHR, 1.40; 95% CI, 0.81-2.39) and younger patients (aHR, 2.33; 95% CI, 1.20-4.51) vs older ones (aHR, 1.36; 95% CI, 0.77-2.39).

Conclusions and Relevance

High-risk plaque found by coronary CTA was associated with a future MACE in a large US population of outpatients with stable chest pain. High-risk plaque may be an additional risk stratification tool, especially in patients with nonobstructive coronary artery disease, younger patients, and women. The importance of findings is limited by low absolute MACE rates and low positive predictive value of high-risk plaque.

Trial Registration

clinicaltrials.gov Indentifier: NCT01174550.

Coronary Computed Tomography Angiography-Specific Definitions of High-Risk Plaque Features Improve Detection of Acute Coronary Syndrome

Background High-risk plaque (HRP) features as detected by coronary computed tomography angiography (CTA) predict acute coronary syndrome (ACS). We sought to determine whether coronary CTA-specific definitions of HRP improve discrimination of patients with ACS as compared with definitions from intravascular ultrasound (IVUS). Methods and Results In patients with suspected ACS, randomized to coronary CTA in the ROMICAT II (Rule Out Myocardial Infarction/Ischemia Using Computer Assisted Tomography II) trial, we retrospectively performed semiautomated quantitative analysis of HRP (including remodeling index, plaque burden as derived by plaque area, low computed tomography attenuation plaque volume) and degree of luminal stenosis and analyzed the performance of traditional IVUS thresholds to detect ACS. Furthermore, we derived CTA-specific thresholds in patients with ACS to detect culprit lesions and applied those to all patients to calculate the discriminatory ability to detect ACS in comparison to IVUS thresholds. Of 472 patients, 255 patients (56±7.8 years; 63% men) had coronary plaque. In 32 patients (6.8%) with ACS, culprit plaques (n=35) differed from nonculprit plaques (n=172) with significantly greater values for all HRP features except minimal luminal area (significantly lower; all P<0.01). IVUS definitions showed good performance while minimal luminal area (odds ratio: 6.82; P=0.014) and plaque burden (odds ratio: 5.71; P=0.008) were independently associated with ACS but not remodeling index (odds ratio: 0.78; P=0.673). Optimized CTA-specific thresholds for plaque burden (area under the curve: 0.832 versus 0.676) and degree of stenosis (area under the curve: 0.826 versus 0.721) showed significantly higher diagnostic performance for ACS as compared with IVUS-based thresholds (all P<0.05) with borderline significance for minimal luminal area (area under the curve: 0.817 versus 0.742; P=0.066). Conclusions CTA-specific definitions of HRP features may improve the discrimination of patients with ACS as compared with IVUS-based definitions. CLINICAL TRIAL REGISTRATION URL: https://www.clinicaltrials.gov . Unique identifier: NCT01084239.

Subclinical Burden of Coronary Artery Calcium in Patients With Coarctation of the Aorta

Coronary computed tomography (CT) angiography is often performed in adults with coarctation of the aorta (CoA) for anatomic assessment. As this population ages, assessment of atherosclerotic cardiovascular disease burden is important. Thus, quantitative and qualitative coronary artery calcium (CAC) scores were assessed for patients with CoA ≥16 years of age, who were seen at a referral center. CoA patients had either coronary CT angiography or chest CT with interpretable coronary information performed for clinical indications (follow-up, preoperative, or for symptoms) from 2004 to 2017. Qualitative CAC was determined based on low-dose CT and lung cancer screening protocols. Quantitative CAC scores were compared with an age- and gender-matched control cohort of patients chosen from an emergency department database of patients who received coronary CT angiography for chest pain evaluation. Atherosclerotic cardiovascular disease 10-year predicted risk scores were calculated for both cohorts. Out of 131 patients with CoA (mean age 46.1 ± 15.3 years), 22 patients (17%) had multivessel atherosclerotic disease on qualitative assessment. In the subgroup of patients ≥40 years, those with CoA were more likely to have a quantitative CAC score ≥400 compared with those without CoA (14% vs 4%, p = 0.02). Median atherosclerotic cardiovascular disease risk score was 8% (interquartile range 2% to 12%) for CoA patients ≥40 years, and 5% (interquartile range 2% to 9%) for patient without CoA ≥40 years. In conclusion, we determined that CoA patients have subclinical atherosclerosis identifiable on CT in high rates when compared with patients without CoA. Atherosclerotic cardiovascular disease should be assessed in these patients for prevention and treatment.

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 AIMS

Total 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.

METHODS

We 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.

RESULTS

Patients (n = 260) with vs. without ACS had higher total CAC score (median 229, 25^th-75^th percentile 75-517 vs. 27, 25^th-75^th 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, 25^th-75^th percentile 4-71 vs. 14, 25^th-75^th 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.

CONCLUSIONS

Total 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.

Perivascular Epicardial Fat Stranding at Coronary CT Angiography: A Marker of Acute Plaque Rupture and Spontaneous Coronary Artery Dissection

Purpose To evaluate the frequency and implications of perivascular fat stranding on coronary computed tomography (CT) angiograms obtained for suspected acute coronary syndrome (ACS). Materials and Methods This retrospective registry study was approved by the institutional review board. The authors reviewed the medical records and images of 1403 consecutive patients (796 men, 607 women; mean age, 52.8 years) who underwent coronary CT angiography at the emergency department from February 2012 to March 2016. Fat attenuation, length and number of circumferential quadrants of the affected segment, and attenuation values in the unaffected epicardial and subcutaneous fat were measured. "Cases" were defined as patients with perivascular fat stranding. Patients with significant stenosis but without fat stranding were considered control subjects. Baseline imaging characteristics, ACS frequency, and results of subsequent downstream testing were compared between cases and control subjects by using two-sample t, Mann-Whitney U, and Fisher tests. Results Perivascular fat stranding was seen in 11 subjects, nine with atherosclerotic lesions and two with spontaneous coronary artery dissections, with a mean fat stranding length of 19.2 mm and circumferential extent averaging 2.9 quadrants. The mean attenuation of perivascular fat stranding, normal epicardial fat, and normal subcutaneous fat was 17, -93.2, and -109.3 HU, respectively (P < .001). Significant differences (P < .05) between cases and control subjects included lower Agatston score, presence of wall motion abnormality, and initial elevation of serum troponin level. ACS frequency was 45.4% in cases and 3.8% in control subjects (P = .001). Conclusion Recognition of perivascular fat stranding may be a helpful additional predictor of culprit lesion and marker of risk for ACS in patients with significant stenosis or spontaneous coronary artery dissection. ^© RSNA, 2018 Online supplemental material is available for this article.

Identification of coronary artery calcification can optimize risk stratification in patients with acute chest pain

BACKGROUND

The number of patients presenting to the emergency department (ED) with suspected acute coronary syndrome (ACS) is substantial. We tested whether identification of coronary artery calcium (CAC) can improve the negative predictive value (NPV) of clinical risk assessment for ACS in patients with acute chest pain.

METHODS AND RESULTS

We included 826 consecutive patients (mean age: 53±11years; 42% female) without known coronary artery disease (CAD) or initially elevated serum biomarkers, whom underwent non-contrast CT, to assess the CAC score, and CT angiography (CTA), to detect coronary stenosis. We analyzed the diagnostic performance of CAC and the Thrombolysis In Myocardial Infarction (TIMI) risk score for our primary outcomes (ACS and obstructive CAD). No CAC was found in 54% (n=444) of all patients, 63% (n=524) had a TIMI score of 0 and 40% (n=328) had both. The prevalence of obstructive CAD was 16% for ≥50% stenosis and 8.7% for ≥70% stenosis. The incidence of ACS was 7.9%, (MI=11, UAP=54). The NPV of CAC=0 was 99.5% for ACS. The NPV of a combination of TIMI score=0 and no CAC was 89% for any CAD (any plaque or stenosis) and 99.7% for ≥50% stenosis. A 100% NPV was found for ≥70% stenosis and ACS, correctly identifying 328 (40%) patients.

CONCLUSIONS

The exclusion of CAC, in combination with clinical risk assessment, has high clinical value in patients with acute chest pain, as it identifies patients at low risk for ACS and obstructive CAD more accurately as compared to clinical risk assessment alone.

Central Core Laboratory versus Site Interpretation of Coronary CT Angiography: Agreement and Association with Cardiovascular Events in the PROMISE Trial

Purpose To assess concordance and relative prognostic utility between central core laboratory and local site interpretation for significant coronary artery disease (CAD) and cardiovascular events. Materials and Methods In the Prospective Multicenter Imaging Study for Evaluation of Chest Pain (PROMISE) trial, readers at 193 North American sites interpreted coronary computed tomographic (CT) angiography as part of the clinical evaluation of stable chest pain. Readers at a central core laboratory also interpreted CT angiography blinded to clinical data, site interpretation, and outcomes. Significant CAD was defined as stenosis greater than or equal to 50%; cardiovascular events were defined as a composite of cardiovascular death or myocardial infarction. Results In 4347 patients (51.8% women; mean age ± standard deviation, 60.4 years ± 8.2), core laboratory and site interpretations were discordant in 16% (683 of 4347), most commonly because of a finding of significant CAD by site but not by core laboratory interpretation (80%, 544 of 683). Overall, core laboratory interpretation resulted in 41% fewer patients being reported as having significant CAD (14%, 595 of 4347 vs 23%, 1000 of 4347; P < .001). Over a median follow-up period of 25 months, 1.3% (57 of 4347) sustained myocardial infarction or cardiovascular death. The C statistic for future myocardial infarction or cardiovascular death was 0.61 (95% confidence interval [CI]: 0.54, 0.68) for the core laboratory and 0.63 (95% CI: 0.56, 0.70) for the sites. Conclusion Compared with interpretation by readers at 193 North American sites, standardized core laboratory interpretation classified 41% fewer patients as having significant CAD. ^© RSNA, 2017 Online supplemental material is available for this article. Clinical trial registration no. NCT01174550.

Age- and sex-based resource utilisation and costs in patients with acute chest pain undergoing cardiac CT angiography: pooled evidence from ROMICAT II and ACRIN-PA trials

OBJECTIVES

To determine resource utilisation according to age and gender-specific subgroups in two large randomized diagnostic trials.

METHODS

We pooled patient-specific data from ACRIN-PA 4005 and ROMICAT II that enrolled subjects with acute chest pain at 14 US sites. Subjects were randomized between a standard work-up and a pathway utilizing cardiac computed tomography angiography (CCTA) and followed for the occurrence of acute coronary syndrome (ACS) and resource utilisation during index hospitalisation and 1-month follow-up. Study endpoints included diagnostic accuracy of CCTA for the detection of ACS as well as resource utilisation.

RESULTS

Among 1240 patients who underwent CCTA, negative predictive value of CCTA to rule out ACS remained very high (≥99.4%). The proportion of patients undergoing additional diagnostic testing and cost increased with age for both sexes (p < 0.001), and was higher in men as compared to women older than 60 years (43.1% vs. 23.4% and $4559 ± 3382 vs. $3179 ± 2562, p < 0.01; respectively). Cost to rule out ACS was higher in men (p < 0.001) and significantly higher for patients older than 60 years ($2860-5935 in men, p < 0.001).

CONCLUSIONS

CCTA strategy in patients with acute chest pain results in varying resource utilisation according to age and gender-specific subgroups, mandating improved selection for advanced imaging.

KEY POINTS

• In this analysis, CAD and ACS increased with age and male gender. • CCTA in patients with acute chest pain results in varying resource utilisation. • Significant increase of diagnostic testing and cost with age for both sexes. • Cost to rule out ACS is higher in men and patients >60 years. • Improved selection of subjects for cardiac CTA result in more resource-driven implementation.

Impact of Coronary Calcification on Clinical Management in Patients With Acute Chest Pain

BACKGROUND

Coronary artery calcification (CAC) may impair diagnostic assessment of coronary computed tomography angiography (CTA). We determined whether CAC affects efficiency of coronary CTA in patients with suspected acute coronary syndrome (ACS).

METHODS AND RESULTS

This is a pooled analysis of ACRIN-PA (American College of Radiology Imaging Network-Pennsylvania) 4005 and the ROMICAT-II trial (Rule Out Myocardial Infarction/Ischemia Using Computer Assisted Tomography) comparing an initial coronary CTA strategy to standard of care in acute chest pain patients. In the CTA arms, we investigated appropriateness of downstream testing, cost, and diagnostic yield to identify patients with obstructive coronary artery disease on subsequent invasive coronary angiography across CAC score strata (Agatston score: 0, >0-10, >10-100, >100-400, >400). Out of 1234 patients (mean age 51±8.8 years), 80 (6.5%) had obstructive coronary artery disease (≥70% stenosis) and 68 (5.5%) had ACS. Prevalence of obstructive coronary artery disease (1%-64%), ACS (1%-44%), downstream testing (4%-72%), and total (2337-8484 US$) and diagnostic cost (2310-6678 US$) increased across CAC strata (P<0.001). As the increase in testing and cost were lower than the increase of ACS rate in patients with CAC>400, cost to diagnose one ACS was lowest in this group (19 283 US$ versus 464 399 US$) as compared with patients without CAC. The diagnostic yield of invasive coronary angiography was highest in patients with CAC>400 (87% versus 38%).

CONCLUSIONS

Downstream testing, total, and diagnostic cost increased with increasing CAC, but were found to be appropriate because obstructive coronary artery disease and ACS were more prevalent in patients with high CAC. In patients with acute chest pain undergoing coronary CTA, cost-efficient testing and excellent diagnostic yield can be achieved even with high CAC burden.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01084239 and NCT00933400.

Influence of Cardiovascular Risk Factors on the Prevalence of Coronary Atherosclerosis in Patients with Angiographically Normal Coronary Arteries

RATIONALE AND OBJECTIVES

Cardiovascular (CV) disease is predominately influenced by CV risk factors and coronary computed tomography angiography (CTA) is capable of detecting early-stage coronary artery disease. We sought to determine the influence of CV risk factors on the prevalence of nonobstructive atherosclerosis in patients with normal-appearing coronary arteries in invasive coronary angiography (ICA).

MATERIALS AND METHODS

In this retrospective analysis, we included 60 consecutive symptomatic patients, having undergone ICA and coronary CTA. Coronary dual source CTA was performed using electrocardiogram-triggered retrospective gated image acquisition at 40%-70% of RR interval (tube voltage 100-120 kV, tube current time product 320-440 mAs, 60 mL contrast, and flow rate 6 mL/s).

RESULTS

Out of 60 patients (32 men, mean age 61 ± 11 years) with a normal coronary artery appearance in ICA, 45 (75%) patients showed atherosclerotic plaque in CTA. Plaque was present in 14 of 60 (23%) left main, 41 of 60 (68%) left anterior descending, 21 of 60 (35%) circumflex coronary arteries, and 24 of 60 (40%) right coronary arteries. More than 15% of all coronary artery segments showed detectable plaques. Interobserver agreement ranged from good to very good on a per-patient, per-vessel, and per-segment level. Patients with presence of plaque were significantly older (P = 0.005) and showed higher incidence of arterial hypertension (P = 0.019) as compared to individuals without coronary plaque in dual source computed tomography.

CONCLUSIONS

The prevalence of coronary atherosclerosis by CTA is substantial in symptomatic patients with normal invasive coronary angiogram. Hypertension and older age significantly influence the prevalence of atherosclerotic plaque and highlight the importance of risk-modifying therapy.