The value of coordinated analysis of multimodal atherosclerotic plaque imaging in the assessment of cardiovascular and cerebrovascular events

Background

Although atherosclerosis (AS) can affect multiple vascular beds, previous studies have focused on the analysis of single-site AS plaques.

Objective

The aim of this study is to explore the differences or similarities in the characteristics of atherosclerotic plaque found in the internal carotid artery, cerebral artery, and coronary artery between patients with atherosclerotic cardiovascular disease (ASCVD) and those without events.

Methods

Patients aged ≥ 18 years who underwent both high-resolution vessel wall imaging (HR-VWI) and coronary computed tomography angiography (CCTA) were retrospectively collected and categorized into the ASCVD group and the non-event group. The plaques were then categorized into culprit plaques, non-culprit plaques, and non-event plaques. Plaque morphological data such as stenosis, stenosis grades, plaque length (PL), plaque volume (PV), minimal lumen area (MLA), enhancement grade, and plaque composition data such as calcified plaque volume (CPV), fibrotic plaque volume (FPV), fibro-lipid plaque volume (FLPV), lipid plaque volume (LPV), calcified plaque volume ratio (CPR), fibrotic plaque volume ratio (FPR), fibro-lipid plaque ratio (FLPR), lipid plaque volume ratio (LPR), intraplaque hemorrhage volume (IPHV), and intraplaque hemorrhage volume ratio (IPHR)were recorded and analyzed.

Results

A total of 44 patients (mean age 66 years, SD 9 years, 28 men) were included. In cervicocephalic plaques, the ASCVD group had more severe stenosis grades (p = 0.030) and demonstrated significant differences in LPV, LPR, and CPV (p = 0.044, 0.030, 0.020) compared with the non-event group. In coronary plaques, the ASCVD group had plaques with greater stenosis (p < 0.001), more severe stenosis grades (p < 0.001), larger volumes (p = 0.001), longer length (p = 0.008), larger FLPV (p = 0.012), larger FPV (p = 0.002), and higher FPR (p = 0.043) compared with the non-event group. There were significant differences observed in stenosis (HR-VWI, CCTA: p < 0.001, p < 0.001), stenosis grades (HR-VWI, CCTA: p < 0.001, p < 0.001), plaque length (HR-VWI, CCTA: p = 0.028, p < 0.001), and plaque volume (HR-VWI, CCTA: p = 0.013, p = 0.018) between the non-event plaque, non-culprit plaque, and culprit plaque. In the image analysis of HR-VWI, there were differences observed between IPHR (p < 0.001), LPR (p = 0.001), FPV (p = 0.011), and CPV (p = 0.015) among the three groups of plaques. FLPV and FPV were significantly different among the three different plaque types from the coronary artery (p = 0.043, p = 0.022).

Conclusion

There is a consistent pattern of change in plaque characteristics between the cervicocephalic and coronary arteries in the same patient.

Insulin resistance is associated with high-risk coronary artery plaque composition in asymptomatic men between 65 and 75 years and no diabetes: A DANCAVAS cross-sectional sub-study

BACKGROUND AND AIMS

Insulin resistance (IR) and pre-diabetes are associated with an increased risk of cardiovascular disease (CVD). We aimed to investigate vulnerable plaque composition in relation to IR and pre-diabetes in asymptomatic non-diabetic men.

METHODS

All participants underwent a contrast-enhanced coronary computed tomography angiography (CCTA) to evaluate coronary artery plaque burden and plaque composition (necrotic core, dense calcium, fibrotic and fibrous-fatty volume). Homeostasis model assessment of IR (HOMA-IR) was used, and participants were stratified into tertiles. Participants underwent a standard oral glucose tolerance test (OGTT) and were categorized into 2 groups (normal glucose tolerance (NGT) or pre-diabetes). A multivariable linear regression model was used to evaluate the association between vulnerable plaque composition and IR or glycemic group.

RESULTS

Four-hundred-and-fifty non-diabetic men without known CAD were included. The mean age was 70 ± 3 years. Participants in the higher HOMA-IR tertile (H-IR) had higher median necrotic plaque volume compared to the lower HOMA-IR tertile (L-IR) (18.2 vs. 11.0 mm3, p = 0.02). H-IR tertile (β 0.37 [95% CI 0.10-0.65], p = 0.008), pack-years (β 0.07 [95% CI 0.007-0.14], p = 0.03) and total atheroma volume (TAV) (β 0.47 [95% CI 0.36-0.57], p < 0.001) remained associated with necrotic plaque volume in the multivariable linear regression model.

CONCLUSIONS

IR was associated with necrotic plaque volume in asymptomatic men without diabetes. Thus, even in asymptomatic men without diabetes, IR seems to have an incremental effect on necrotic plaque volume and vulnerable plaque composition.

Role of computed tomography cardiac angiography in acute chest pain syndromes

Use of CT coronary angiography (CTCA) to evaluate chest pain has rapidly increased over the recent years. While its utility in the diagnosis of coronary artery disease in stable chest pain syndromes is clear and is strongly endorsed by international guidelines, the role of CTCA in the acute setting is less certain. In the low-risk setting, CTCA has been shown to be accurate, safe and efficient but inherent low rates of adverse events in this population and the advent of high-sensitivity troponin testing have left little room for CTCA to show any short-term clinical benefit.In higher-risk populations, CTCA has potential to fulfil a gatekeeper role to invasive angiography. The high negative predictive value of CTCA is maintained while also identifying non-obstructive coronary disease and alternative diagnoses in the substantial group of patients presenting with chest pain who do not have type 1 myocardial infarction. For those with obstructive coronary disease, CTCA provides accurate assessment of stenosis severity, characterisation of high-risk plaque and findings associated with perivascular inflammation. This may allow more appropriate selection of patients to proceed to invasive management with no disadvantage in outcomes and can provide a more comprehensive risk stratification to guide both acute and long-term management than routine invasive angiography.

Characteristics of conventional high-risk coronary plaques and a novel CT defined thin-cap fibroatheroma in patients undergoing CCTA with stable chest pain

BACKGROUND

Coronary computed tomography angiography (CCTA) can identify high-risk coronary plaque types. However, the inter-observer variability for high-risk plaque features, including low attenuation plaque (LAP), positive remodelling (PR), and the Napkin-Ring sign (NRS), may reduce their utility, especially amongst less experienced readers.

METHODOLOGY

In a prospective study, we compared the prevalence, location and inter-observer variability of both conventional CT-defined high-risk plaques with a novel index based on quantifying the ratio of necrotic core to fibrous plaque using individualised X-ray attenuation cut-offs (the CT-defined thin-cap fibroatheroma - CT-TCFA) in 100 patients followed-up for 7 years.

RESULTS

In total, 346 plaques were identified in all patients. Seventy-two (21%) of all plaques were classified by conventional CT parameters as high-risk (either NRS or PR and LAP combined), and 43 (12%) of plaques were considered high-risk using the novel CT-TCFA definition of (Necrotic Core/fibrous plaque ratio of >0.9). The majority (80%) of the high-risk plaques (LAP&PR, NRS and CT-TCFA) were located in the proximal and mid-LAD and RCA. The kappa co-efficient of inter-observer variability (k) for NRS was 0.4 and for PR and LAP combined 0.4. While the kappa co-efficient of inter-observer variability (k) for the new CT-TCFA definition was 0.7. During follow-up, patients with either conventional high-risk plaques or CT-TCFAs were significantly more likely to have MACE (Major adverse cardiovascular events) compared to patients without coronary plaques (p value 0.03 & 0.03, respectively).

CONCLUSION

The novel CT-TCFA is associated with MACE and has improved inter-observer variability compared with current CT-defined high-risk plaques.

Coronary low-attenuation plaque and high-sensitivity cardiac troponin

OBJECTIVE

In patients with acute chest pain who have had myocardial infarction excluded, plasma cardiac troponin I concentrations ≥5 ng/L are associated with risk of future adverse cardiovascular events. We aim to evaluate the association between cardiac troponin and coronary plaque composition in such patients.

METHODS

In a prespecified secondary analysis of a prospective cohort study, blinded quantitative plaque analysis was performed on 242 CT coronary angiograms of patients with acute chest pain in whom myocardial infarction was excluded. Patients were stratified by peak plasma cardiac troponin I concentration ≥5 ng/L or <5 ng/L. Associations were assessed using univariable and multivariable logistic regression analyses.

RESULTS

The cohort was predominantly middle-aged (62±12 years) men (69%). Patients with plasma cardiac troponin I concentration ≥5 ng/L (n=161) had a higher total (median 33% (IQR 0-47) vs 0% (IQR 0-33)), non-calcified (27% (IQR 0-37) vs 0% (IQR 0-28)), calcified (2% (IQR 0-8) vs 0% (IQR 0-3)) and low-attenuation (1% (IQR 0-3) vs 0% (IQR 0-1)) coronary plaque burden compared with those with concentrations <5 ng/L (n=81; p≤0.001 for all). Low-attenuation plaque burden was independently associated with plasma cardiac troponin I concentration ≥5 ng/L after adjustment for clinical characteristics (adjusted OR per doubling 1.62 (95% CI 1.17 to 2.32), p=0.005) or presence of any visible coronary artery disease (adjusted OR per doubling 1.57 (95% CI 1.07 to 2.37), p=0.026).

CONCLUSION

In patients with acute chest pain but without myocardial infarction, plasma cardiac troponin I concentrations ≥5 ng/L are associated with greater burden of low-attenuation coronary plaque.

Subclinical Coronary Atherosclerosis and Risk for Myocardial Infarction in a Danish Cohort : A Prospective Observational Cohort Study

BACKGROUND

Coronary atherosclerosis may develop at an early age and remain latent for many years.

OBJECTIVE

To define characteristics of subclinical coronary atherosclerosis associated with the development of myocardial infarction.

DESIGN

Prospective observational cohort study.

SETTING

Copenhagen General Population Study, Denmark.

PARTICIPANTS

9533 asymptomatic persons aged 40 years or older without known ischemic heart disease.

MEASUREMENTS

Subclinical coronary atherosclerosis was assessed with coronary computed tomography angiography conducted blinded to treatment and outcomes. Coronary atherosclerosis was characterized according to luminal obstruction (nonobstructive or obstructive [≥50% luminal stenosis]) and extent (nonextensive or extensive [one third or more of the coronary tree]). The primary outcome was myocardial infarction, and the secondary outcome was a composite of death or myocardial infarction.

RESULTS

A total of 5114 (54%) persons had no subclinical coronary atherosclerosis, 3483 (36%) had nonobstructive disease, and 936 (10%) had obstructive disease. Within a median follow-up of 3.5 years (range, 0.1 to 8.9 years), 193 persons died and 71 had myocardial infarction. The risk for myocardial infarction was increased in persons with obstructive (adjusted relative risk, 9.19 [95% CI, 4.49 to 18.11]) and extensive (7.65 [CI, 3.53 to 16.57]) disease. The highest risk for myocardial infarction was noted in persons with obstructive-extensive subclinical coronary atherosclerosis (adjusted relative risk, 12.48 [CI, 5.50 to 28.12]) or obstructive-nonextensive (adjusted relative risk, 8.28 [CI, 3.75 to 18.32]). The risk for the composite end point of death or myocardial infarction was increased in persons with extensive disease, regardless of degree of obstruction-for example, nonobstructive-extensive (adjusted relative risk, 2.70 [CI, 1.72 to 4.25]) and obstructive-extensive (adjusted relative risk, 3.15 [CI, 2.05 to 4.83]).

LIMITATION

Mostly White persons were studied.

CONCLUSION

In asymptomatic persons, subclinical, obstructive coronary atherosclerosis is associated with a more than 8-fold elevated risk for myocardial infarction.

PRIMARY FUNDING SOURCE

AP Møller og Hustru Chastine Mc-Kinney Møllers Fond.

Does Coronary Plaque Morphology Matter Beyond Plaque Burden?

PURPOSE OF REVIEW

Imaging of adverse coronary plaque features by coronary computed tomography angiography (CCTA) has advanced greatly and at a fast pace. We aim to describe the evolution, present and future in plaque analysis, and its value in comparison to plaque burden.

RECENT FINDINGS

Recently, it has been demonstrated that in addition to plaque burden, quantitative and qualitative assessment of coronary plaque by CCTA can improve the prediction of future major adverse cardiovascular events in diverse coronary artery disease scenarios. The detection of high-risk non-obstructive coronary plaque can lead to higher use of preventive medical therapies such as statins and aspirin, help identify culprit plaque, and differentiate between myocardial infarction types. Even more, over traditional plaque burden, plaque analysis including pericoronary inflammation can potentially be useful tools for tracking disease progression and response to medical therapy. The identification of the higher risk phenotypes with plaque burden, plaque characteristics, or ideally both can allow the allocation of targeted therapies and potentially monitor response. Further observational data are now required to investigate these key issues in diverse populations, followed by rigorous randomized controlled trials.

Computed tomography coronary angiography in non-ST-segment elevation myocardial infarction

Electrocardiography and high-sensitivity cardiac troponin testing are routinely applied as the initial step for clinical evaluation of patients with suspected non-ST-segment elevation myocardial infarction. Once diagnosed, patients with non-ST-segment elevation myocardial infarction are commenced on antithrombotic and secondary preventative therapies before undergoing invasive coronary angiography to determine the strategy of coronary revascularisation. However, this clinical pathway is imperfect and can lead to challenges in the diagnosis, management, and clinical outcomes of these patients. Computed tomography coronary angiography (CTCA) has increasingly been utilised in the setting of patients with suspected non-ST-segment elevation myocardial infarction, where it has an important role in avoiding unnecessary invasive coronary angiography and reducing downstream non-invasive functional testing for myocardial ischaemia. CTCA is an excellent gatekeeper for the cardiac catheterisation laboratory. In addition, CTCA provides complementary information for patients with myocardial infarction in the absence of obstructive coronary artery disease and highlights alternative or incidental diagnoses for those with cardiac troponin elevation. However, the routine application of CTCA has yet to demonstrate an impact on subsequent major adverse cardiovascular events. There are several ongoing studies evaluating CTCA and its associated technologies that will define and potentially expand its application in patients with suspected or diagnosed non-ST-segment elevation myocardial infarction. We here review the current evidence relating to the clinical application of CTCA in patients with non-ST-segment elevation myocardial infarction and highlight the areas where CTCA is likely to have an increasing important role and impact for our patients.

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

BACKGROUND

In patients with stable chest pain, computed tomography (CT) plaque burden is an independent predictor of future coronary events.

OBJECTIVES

The 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.

METHODS

In 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.

RESULTS

Following 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).

CONCLUSIONS

In 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).

Distinguishing Type 1 from Type 2 Myocardial Infarction by Using CT Coronary Angiography

Purpose

To determine whether quantitative plaque characterization by using CT coronary angiography (CTCA) can discriminate between type 1 and type 2 myocardial infarction.

Materials and Methods

This was a secondary analysis of two prospective studies (ClinicalTrials.gov registration nos. NCT03338504 [2014-2019] and NCT02284191 [2018-2020]) that performed blinded quantitative plaque analysis on findings from CTCA in participants with type 1 myocardial infarction, type 2 myocardial infarction, and chest pain without myocardial infarction. Logistic regression analyses were performed to identify predictors of type 1 myocardial infarction.

Results

Overall, 155 participants (mean age, 64 years ± 12 [SD]; 114 men) and 36 participants (mean age, 67 years ± 12; 19 men) had type 1 and type 2 myocardial infarction, respectively, and 136 participants (62 years ± 12; 78 men) had chest pain without myocardial infarction. Participants with type 1 myocardial infarction had greater total (median, 44% [IQR: 35%-50%] vs 35% [IQR: 29%-46%]), noncalcified (39% [IQR: 31%-46%] vs 34% [IQR: 29%-40%]), and low-attenuation (4.15% [IQR: 1.88%-5.79%] vs 1.64% [IQR: 0.89%-2.28%]) plaque burdens (P < .05 for all) than those with type 2. Participants with type 2 myocardial infarction had similar low-attenuation plaque burden to those with chest pain without myocardial infarction (P = .4). Low-attenuation plaque was an independent predictor of type 1 myocardial infarction (adjusted odds ratio, 3.44 [95% CI: 1.84, 6.96]; P < .001), with better discrimination than noncalcified plaque burden and maximal area of coronary stenosis (C statistic, 0.75 [95% CI: 0.67, 0.83] vs 0.62 [95% CI: 0.53, 0.71] and 0.61 [95% CI: 0.51, 0.70] respectively; P ≤ .001 for both).

Conclusion

Higher low-attenuation coronary plaque burden in patients with type 1 myocardial infarction may help distinguish these patients from those with type 2 myocardial infarction.Keywords: Ischemia/Infarction, CT Angiography, Quantitative CTClinical trial registration nos. NCT03338504 and NCT02284191 Supplemental material is available for this article. © RSNA, 2022.

Quantitative assessment of atherosclerotic plaque, recent progress and current limitations

An important advantage of computed tomography coronary angiography (CCTA) is its ability to visualize the presence and severity of atherosclerotic plaque, rather than just assessing coronary artery stenoses. Until recently, assessment of plaque subtypes on CCTA relied on visual assessment of the extent of calcified/non-calcified plaque, or visually identifying high-risk plaque characteristics. Recent software developments facilitate the quantitative assessment of plaque volume or burden on CCTA, and the identification of subtypes of plaque based on their attenuation density. These techniques have shown promise in single and multicenter studies, demonstrating that the amount and type of plaque are associated with subsequent cardiac events. However, there are a number of limitations to the application of these techniques, including the limitations imposed by the spatial resolution of current CT scanners, challenges from variations between reconstruction algorithms, and the additional time to perform these assessments. At present, these are a valuable research technique, but not yet part of routine clinical practice. Future advances that improve CT resolution, standardize acquisition techniques and reconstruction algorithms and automate image analysis will improve the clinical utility of these techniques. This review will discuss the technical aspects of quantitative plaque analysis and present pro and con arguments for the routine use of quantitative plaque analysis on CCTA.

Clinical Relevance of Coronary Computed Tomography Angiography Beyond Coronary Artery Stenosis

BACKGROUND

 The capabilities of coronary computed tomography angiography (CCTA) have advanced significantly in the past decade. Its capacity to detect stenotic coronary arteries safely and consistently has led to a marked decline in invasive diagnostic angiography. However, CCTA can do much more than identify coronary artery stenoses.

METHOD

 This review discusses applications of CCTA beyond coronary stenosis assessment, focusing in particular on the visual and quantitative analysis of atherosclerotic plaque.

RESULTS

 Established signs of visually assessed high-risk plaque on CT include positive remodeling, low-attenuation plaque, spotty calcification, and the napkin-ring sign, which correlate with the histological thin-cap fibroatheroma. Recently, quantification of plaque subtypes has further improved the assessment of coronary plaque on CT. Quantitatively assessed low-attenuation plaque, which correlates with the necrotic core of the thin-cap fibroatheroma, has demonstrated superiority over stenosis severity and coronary calcium score in predicting subsequent myocardial infarction. Current research aims to use radiomic and machine learning methods to further improve our understanding of high-risk atherosclerotic plaque subtypes identified on CCTA.

CONCLUSION

 Despite rapid technological advances in the field of coronary computed tomography angiography, there remains a significant lag in routine clinical practice where use is often limited to lumenography. We summarize some of the most promising techniques that significantly improve the diagnostic and prognostic potential of CCTA.

KEY POINTS

  · In addition to its ability to determine severity of luminal stenoses, CCTA provides important prognostic information by evaluating atherosclerotic plaque.. · Simple scoring systems such as the segment involved score or the CT-adapted Leaman score can provide more prognostic information on major adverse coronary events compared to traditional risk factors such as presence of hypertension or diabetes.. · CT signs of high-risk plaque, including positive remodeling, low-attenuation plaque, spotty calcification, and the napkin-ring sign, are significantly more likely to predict acute coronary syndromes.. · Quantitative plaque assessment can provide precise description of volume and burden of plaque subtypes and have been found to predict subsequent myocardial infarction better than cardiovascular risk scores, calcium scoring and severity of coronary artery stenoses.. · Machine learning techniques have the potential to automate risk stratification and enhance health economy, even though present clinical applications are limited. In this era of "big data" they are an exciting avenue for future research..

CITATION FORMAT

· Meah MN, Williams MC. Clinical Relevance of Coronary Computed Tomography Angiography Beyond Coronary Artery Stenosis. Fortschr Röntgenstr 2021; 193: 1162 - 1170.

Prognostic Value of Coronary CT Angiography in Patients With Non-ST-Segment Elevation Acute Coronary Syndromes

BACKGROUND

Severity and extent of coronary artery disease (CAD) assessed by invasive coronary angiography (ICA) guide treatment and may predict clinical outcome in patients with non-ST-segment elevation acute coronary syndrome (NSTEACS).

OBJECTIVES

This study tested the hypothesis that coronary computed tomography angiography (CTA) is equivalent to ICA for risk assessment in patients with NSTEACS.

METHODS

The VERDICT (Very Early Versus Deferred Invasive Evaluation Using Computerized Tomography in Patients With Acute Coronary Syndromes) trial evaluated timing of treatment in relation to outcome in patients with NSTEACS and included a clinically blinded coronary CTA conducted prior to ICA. Severity of CAD was defined as obstructive (coronary stenosis ≥50%) or nonobstructive. Extent of CAD was defined as high risk (obstructive left main or proximal left anterior descending artery stenosis and/or multivessel disease) or non-high risk. The primary endpoint was a composite of all-cause death, nonfatal recurrent myocardial infarction, hospital admission for refractory myocardial ischemia, or heart failure.

RESULTS

Coronary CTA and ICA were conducted in 978 patients. During a median follow-up time of 4.2 years (interquartile range: 2.7 to 5.5 years), the primary endpoint occurred in 208 patients (21.3%). The rate of the primary endpoint was up to 1.7-fold higher in patients with obstructive CAD compared with in patients with nonobstructive CAD as defined by coronary CTA (hazard ratio [HR]: 1.74; 95% confidence interval [CI]: 1.22 to 2.49; p = 0.002) or ICA (HR: 1.54; 95% CI: 1.13 to 2.11; p = 0.007). In patients with high-risk CAD, the rate of the primary endpoint was 1.5-fold higher compared with the rate in those with non-high-risk CAD as defined by coronary CTA (HR: 1.56; 95% CI: 1.18 to 2.07; p = 0.002). A similar trend was noted for ICA (HR: 1.28; 95% CI: 0.98 to 1.69; p = 0.07).

CONCLUSIONS

Coronary CTA is equivalent to ICA for the assessment of long-term risk in patients with NSTEACS. (Very Early Versus Deferred Invasive Evaluation Using Computerized Tomography in Patients With Acute Coronary Syndromes [VERDICT]; NCT02061891).

The year 2019 in the European Heart Journal-Cardiovascular Imaging: Part I

The European Heart Journal-Cardiovascular Imaging was launched in 2012 and has during these years become one of the leading multimodality cardiovascular imaging journals. The journal is now established as one of the top cardiovascular journals and is the most important cardiovascular imaging journal in Europe. The most important studies published in our Journal in 2019 will be highlighted in two reports. Part I of the review will focus on studies about myocardial function and risk prediction, myocardial ischaemia, and emerging techniques in cardiovascular imaging, while Part II will focus on valvular heart disease, heart failure, cardiomyopathies, and congenital heart disease.

Coronary Atherosclerosis Imaging

Identifying patients at increased risk of coronary artery disease, before the atherosclerotic complications become clinically evident, is the aim of cardiovascular prevention. Imaging techniques provide direct assessment of coronary atherosclerotic burden and pathological characteristics of atherosclerotic lesions which may predict the progression of disease. Atherosclerosis imaging has been traditionally based on the evaluation of coronary luminal narrowing and stenosis. However, the degree of arterial obstruction is a poor predictor of subsequent acute events. More recent techniques focus on the high-resolution visualization of the arterial wall and the coronary plaques. Most acute coronary events are triggered by plaque rupture or erosion. Hence, atherosclerotic plaque imaging has generally focused on the detection of vulnerable plaque prone to rupture. However, atherosclerosis is a dynamic process and the plaque morphology and composition may change over time. Most vulnerable plaques undergo progressive transformation from high-risk to more stable and heavily calcified lesions, while others undergo subclinical rupture and healing. Although extensive plaque calcification is often associated with stable atherosclerosis, the extent of coronary artery calcification strongly correlates with the degree of atherosclerosis and with the rate of future cardiac events. Inflammation has a central role in atherogenesis, from plaque formation to rupture, hence in the development of acute coronary events. Morphologic plaque assessment, both invasive and non-invasive, gives limited information as to the current activity of the atherosclerotic disease. The addition of nuclear imaging, based on radioactive tracers targeted to the inflammatory components of the plaques, provides a highly sensitive assessment of coronary disease activity, thus distinguishing those patients who have stable disease from those with active plaque inflammation.

Reproducibility of quantitative coronary computed tomography angiography in asymptomatic individuals and patients with acute chest pain

Purpose

Quantitative computed tomography (QCT) provides important prognostic information of coronary atherosclerosis. We investigated intraobserver and interobserver QCT reproducibility in asymptomatic individuals, patients with acute chest pain without acute coronary syndrome (ACS), and patients with acute chest pain and ACS.

Methods

Fifty patients from each cohort, scanned between 01/02/2010-14/11/2013 and matched according to age and gender, were retrospectively assessed for inclusion. Patients with no coronary artery disease, previous coronary artery bypass graft surgery, and poor image quality were excluded. Coronary atherosclerosis was measured semi-automatically by 2 readers. Reproducibility of minimal lumen area (MLA), minimal lumen diameter (MLD), area stenosis, diameter stenosis, vessel remodeling, plaque eccentricity, plaque burden, and plaque volumes was assessed using concordance correlation coefficient (CCC), Bland-Altman, coefficient of variation, and Cohen’s kappa.

Results

A total of 84 patients (63 matched) were included. Intraobserver and interobserver reproducibility estimates were acceptable for MLA (CCC = 0.94 and CCC = 0.91, respectively), MLD (CCC = 0.92 and CCC = 0.86, respectively), plaque burden (CCC = 0.86 and CCC = 0.80, respectively), and plaque volume (CCC = 0.97 and CCC = 0.95, respectively). QCT detected area and diameter stenosis ≥50%, positive remodeling, and eccentric plaque with moderate-good intraobserver and interobserver reproducibility (kappa: 0.64–0.66, 0.69–0.76, 0.46–0.48, and 0.41–0.62, respectively). Reproducibility of plaque composition decreased with decreasing plaque density (intraobserver and interobserver CCC for dense calcium (>0.99; 0.98), fibrotic (0.96; 0.93), fibro-fatty (0.95; 0.91), and necrotic core tissue (0.89; 0.84). Reproducibility generally decreased with worsening clinical risk profile.

Conclusions

Semi-automated QCT of coronary plaque morphology is reproducible, albeit with some decline in reproducibility with worsening patient risk profile.