All-cause mortality benefit of coronary revascularization vs. medical therapy in patients without known coronary artery disease undergoing coronary computed tomographic angiography: results from CONFIRM (COronary CT Angiography EvaluatioN For Clinical Outcomes: An InteRnational Multicenter Registry)

Computed Tomography Evaluation of Coronary Atherosclerosis: The Road Travelled, and What Lies Ahead

Coronary CT angiography (CCTA) is now endorsed by all major cardiology guidelines for the investigation of chest pain and assessment for coronary artery disease (CAD) in appropriately selected patients. CAD is a leading cause of morbidity and mortality. There is extensive literature to support CCTA diagnostic and prognostic value both for stable and acute symptoms. It enables rapid and cost-effective rule-out of CAD, and permits quantification and characterization of coronary plaque and associated significance. In this comprehensive review, we detail the road traveled as CCTA evolved to include quantitative assessment of plaque stenosis and extent, characterization of plaque characteristics including high-risk features, functional assessment including fractional flow reserve-CT (FFR-CT), and CT perfusion techniques. The state of current guideline recommendations and clinical applications are reviewed, as well as future directions in the rapidly advancing field of CT technology, including photon counting and applications of artificial intelligence (AI).

Analysis of Coronary Angiography and Revascularization Rates Made Over 5 Years in Public Institutions in Türkiye

BACKGROUND

Coronary angiography is currently the gold standard anatomic imaging method used to diagnose obstructive epicardial coronary artery disease. In patients with critical coronary stenosis, surgical or percutaneous revascularization is provided. Normal coronary artery ratio in coronary angiography is an indirect indicator of patient selection quality. The aim of our study is to evaluate the efficiency of coronary angiography by examining the revascularization rates according to years in patients who underwent coronary angiography.

METHODS

Revascularization rates will be determined by analyzing retrospectively the number of patients who underwent coronary angiography in our country between 2016 and 2021 and were revascularized interventionally or surgically. The number of patients who underwent percutaneous, surgical, and total revascularization were proportioned to the number of coronary angiography, and their percentages were determined.

RESULTS

From 2016 to 2019, there was a continuous increase in the number of coronary angiography. In 2020, the lowest coronary angiography numbers (n = 222.159) of the last 6 years were seen with the effect of the COVID-19 pandemic. In 2021, it was observed that the number of coronary angiography increased again with the relaxation of pandemic measures and the approaching of hospital admissions to old levels. It is seen that revascularization is performed in up to one-third of the patients who underwent coronary angiography.

CONCLUSION

Similar to the rest of the world, revascularization rates as a result of coronary angiography procedures performed in our country are low. With this result, it should not be concluded that coronary angiography is not used effectively; on the contrary, the efficiency of coronary angiography can be increased by more effective use of noninvasive tests.

Non-invasive Global and Regional Myocardial Work Predicts High-Risk Stable Coronary Artery Disease Patients With Normal Segmental Wall Motion and Left Ventricular Function

Background: Previous studies suggested that myocardial work (MW) may identify abnormalities in the left ventricular (LV) function and establish a more sensitive index for LV dysfunction at the early stage. This study aimed to explore the value of global and regional MW parameters in predicting high-risk stable coronary artery disease (SCAD) patients with normal wall motion and preserved LV function. Patients and Methods: A total of 131 patients, who were clinically diagnosed as SCAD with normal wall motion and LV function, were finally included in this study. Global MW parameters, including global work index (GWI), global constructive work (GCW), global waste work (GWW), and global work efficiency (GWE) were measured with non-invasive LV pressure-strain loops constructed from speckle-tracking echocardiography. Regional myocardial work index (RWI) and work efficiency (RWE) were also calculated according to the perfusion territory of each major coronary artery. All patients underwent coronary angiography and were divided into the high-risk SCAD group, the non-high-risk SCAD group, and the No SCAD group according to the range and degrees of coronary arteries stenosis. Results: The global longitudinal strain (GLS), GWI and GCW were statistically different (P < 0.001) among the three groups. In the high-risk SCAD group, GLS, GWI, and GCW were significantly lower than the other two groups (P < 0.05). Receiver operating characteristic analysis demonstrated GWI and GCW could predict high-risk SCAD at a cutoff value of 1,808 mm Hg% (sensitivity, 52.6%; specificity, 87.8%; predictive positive value, 76.3%; predictive negative value, 69.9%) and 2,308 mm Hg% (sensitivity, 80.7%; specificity, 64.9%; predictive positive value, 63.3%; predictive negative value, 80.0%), respectively. Multivariate analyses showed that carotid plaque, decreased GWI, and GCW was independently related to high-risk SCAD. The cutoff values of RWI_LAD, RWI_LCX, and RWI_RCA were 2,156, 1,929, and 1,983 mm Hg% in predicting high-risk SCAD, respectively (P < 0.001). When we combined RWI in two or three perfusion regions, the diagnostic performance of SCAD was improved (P < 0.001). Conclusions: Both global and regional MW parameters have great potential in non-invasively predicting high-risk SCAD patients with normal wall motion and preserved LV function, contributing to the early identification of high-risk patients who may benefit from revascularization therapy.

SIRM-SIC appropriateness criteria for the use of Cardiac Computed Tomography. Part 1: Congenital heart diseases, primary prevention, risk assessment before surgery, suspected CAD in symptomatic patients, plaque and epicardial adipose tissue characterization, and functional assessment of stenosis

In the past 20 years, Cardiac Computed Tomography (CCT) has become a pivotal technique for the noninvasive diagnostic work-up of coronary and cardiac diseases. Continuous technical and methodological improvements, combined with fast growing scientific evidence, have progressively expanded the clinical role of CCT. Recent large multicenter randomized clinical trials documented the high prognostic value of CCT and its capability to increase the cost-effectiveness of the management of patients with suspected CAD. In the meantime, CCT, initially perceived as a simple non-invasive technique for studying coronary anatomy, has transformed into a multiparametric "one-stop-shop" approach able to investigate the heart in a comprehensive way, including functional, structural and pathophysiological biomarkers. In this complex and revolutionary scenario, it is urgently needed to provide an updated guide for the appropriate use of CCT in different clinical settings. This manuscript, endorsed by the Italian Society of Medical and Interventional Radiology (SIRM) and by the Italian Society of Cardiology (SIC), represents the first of two consensus documents collecting the expert opinion of Radiologists and Cardiologists about current appropriate use of CCT.

Clinical risk factors and atherosclerotic plaque extent to define risk for major events in patients without obstructive coronary artery disease: the long-term coronary computed tomography angiography CONFIRM registry

AIMS

In patients without obstructive coronary artery disease (CAD), we examined the prognostic value of risk factors and atherosclerotic extent.

METHODS AND RESULTS

Patients from the long-term CONFIRM registry without prior CAD and without obstructive (≥50%) stenosis were included. Within the groups of normal coronary computed tomography angiography (CCTA) (N = 1849) and non-obstructive CAD (N = 1698), the prognostic value of traditional clinical risk factors and atherosclerotic extent (segment involvement score, SIS) was assessed with Cox models. Major adverse cardiac events (MACE) were defined as all-cause mortality, non-fatal myocardial infarction, or late revascularization. In total, 3547 patients were included (age 57.9 ± 12.1 years, 57.8% male), experiencing 460 MACE during 5.4 years of follow-up. Age, body mass index, hypertension, and diabetes were the clinical variables associated with increased MACE risk, but the magnitude of risk was higher for CCTA defined atherosclerotic extent; adjusted hazard ratio (HR) for SIS >5 was 3.4 (95% confidence interval [CI] 2.3-4.9) while HR for diabetes and hypertension were 1.7 (95% CI 1.3-2.2) and 1.4 (95% CI 1.1-1.7), respectively. Exclusion of revascularization as endpoint did not modify the results. In normal CCTA, presence of ≥1 traditional risk factors did not worsen prognosis (log-rank P = 0.248), while it did in non-obstructive CAD (log-rank P = 0.025). Adjusted for SIS, hypertension and diabetes predicted MACE risk in non-obstructive CAD, while diabetes did not increase risk in absence of CAD (P-interaction = 0.004).

CONCLUSION

Among patients without obstructive CAD, the extent of CAD provides more prognostic information for MACE than traditional cardiovascular risk factors. An interaction was observed between risk factors and CAD burden, suggesting synergistic effects of both.

Coronary CT angiography: a guide to examination, interpretation, and clinical indications

INTRODUCTION

The introduction of Cardiac Computed Tomography (CCT) has changed the paradigm in the field of diagnostic cardiovascular medicine. CCT is the primary tool in the assessment of suspected Coronary Artery Disease (CAD) and should be followed by functional assessment when needed to stratify disease and to plan potential interventional or surgical therapy.

AREAS COVERED

We provided the current state of the knowledge on the main aspects of technique of examination, image interpretation and clinical indications. We have focused our attention on the basic routine applications and activities.

EXPERT OPINION

The primary role of CCT in suspected CAD will progressively become the standard approach. In general, any situation in which anatomy of the heart and thoracic vessels/structures is mandatory must be approached using CT first, whenever possible. The quantity and quality of information that can be provided by CCT is big and the operators should learn how to deal with this information. On the other hand, CCT is only apparently a straightforward and simple examination. It is actually the most complex diagnostic procedure that can be performed on CT and requires highly skilled operators and state-of-art-technology.

Coronary atherosclerosis as the main endpoint of non-invasive imaging in cardiology: a narrative review

The change of paradigm determined by the introduction of cardiac computed tomography (CCT) in the field of cardiovascular medicine has allowed new evidence to emerge. These evidences point towards a major role, probably the most important one in terms of prognostic impact, in the detection, characterization and quantification of atherosclerosis as the main driver and endpoint for the management of coronary artery disease (CAD). Extensive literature has been published in the last decade with large numbers and patients' populations, investigating several aspects and correlations between atherosclerotic plaque features and risk factors; also, the relationship between plaque features, both with qualitative and quantitative approaches, and cardiovascular events has been investigated. More recent studies have also pointed out the relationship between the knowledge and classification of sub-clinical atherosclerosis and the induced modification of medical therapy (both aggressiveness and compliance) that is most likely able to increase the effect of anti-atherosclerotic drugs, hence significantly improving prognosis. Non-invasive assessment of CAD by means of CCT is becoming the primary tool for management and also the most important parameter for the comprehension of natural history of CAD and how the therapies we adopt are affecting plaque burden as a whole. In this review we will address the modern concepts of CAD driven understanding and management of cardiovascular disease.

Implementation of coronary computed tomography angiography as nationally recommended first-line test in patients with suspected chronic coronary syndrome: impact on the use of invasive coronary angiography and revascularization

AIMS

To investigate the impact of applying coronary computed tomography angiography (CCTA), as the recommended first-line diagnostic test in patients with suspected chronic coronary syndrome (CCS) on the use of invasive coronary angiography (ICA) and revascularization practice.

METHODS AND RESULTS

We included all patients undergoing a first-time CCTA (n = 53555) and first-time ICA (n = 41451) from 2008 to 2017 due to suspected CCS in Western Denmark (3.3 million inhabitants). The number of CCTA procedures increased from 352 (2008) to 7739 (2017) (2098%), ICA examinations declined from 4538 to 3766 (17%). The average proportion of no- or non-obstructive coronary artery disease by CCTA was 77.5%. Referral to ICA after CCTA occurred in 16.9% of patients in 2008-10 vs. 13.9% in 2014-17 (P < 0.0001). Revascularization in patients referred to ICA after CCTA increased from 33.8% in 2008-10 vs. 44.4% in 2014-17 (P < 0.0001). The revascularization proportion in patients undergoing ICA with no preceding CCTA was 32.3% in 2008-10 vs. 33.3% in (2014-17) (P = 0.1063). Stratified by age, the overall revascularization proportion increased in the younger age groups and was unchanged or decreased in older age groups: <50 years: 60% increase, 50-59 years: 33% increase, 60-69 years: 0%, and >70 years: 9.5% decrease.

CONCLUSION

The introduction of CCTA as a first-line diagnostic test in patients with suspected CCS does not associate with increased use of invasive angiography and seems to have facilitated a more appropriate revascularization practice.

Association of gamma-glutamyl transferase with subclinical coronary atherosclerosis and cardiac outcomes in non-alcoholics

In an asymptomatic population, we determined the relationship between serum gamma-glutamyl transferase (GGT) and subclinical atherosclerosis, using coronary computed tomography angiography (CCTA). This was a retrospective observational cohort study which analyzed 5120 consecutive asymptomatic individuals with no prior history of coronary artery disease or significant alcohol intake who voluntarily underwent CCTA as part of a general health examination. All subjects were stratified into tertiles based on GGT levels. Degree and extent of subclinical coronary atherosclerosis were evaluated using CCTA. Cardiac events were a composite of all-cause death, myocardial infarction, unstable angina, and coronary revascularization. After adjustment for cardiovascular risk factors, there were no significant differences among GGT tertiles in terms of adjusted odds ratios for non-calcified and mixed plaques. The risk of any atherosclerotic and calcified plaques, significant stenosis, multi-vessel disease, and significant stenosis in the left main or proximal left anterior descending artery was higher in the third GGT tertile than in the first tertile (all p < 0.05). Over a median 5.4-year follow-up, the third GGT tertile had significant adjusted hazards ratios for cardiac events than did the first GGT tertile, even after stepwise adjustment for cardiovascular risk factors (all p < 0.01). In asymptomatic individuals, elevated GGT was independently associated with high-risk feature atherosclerosis and poorer cardiac outcomes.

Complete versus incomplete coronary revascularization: definitions, assessment and outcomes

Coronary artery disease is the leading cause of morbidity and mortality worldwide. Selected patients with obstructive coronary artery disease benefit from revascularization with percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG) surgery. Many (but not all) studies have demonstrated increased survival and greater freedom from adverse cardiovascular events after complete revascularization (CR) than after incomplete revascularization (ICR) in patients with multivessel disease. However, achieving CR after PCI or CABG surgery might not be feasible owing to patient comorbidities, anatomical factors, and technical or procedural considerations. These factors also mean that comparisons between CR and ICR are subject to multiple confounders and are difficult to understand or apply to real-world clinical practice. In this Review, we summarize and critically appraise the evidence linking various types of ICR to adverse outcomes in patients with multivessel disease and stable ischaemic heart disease, non-ST-segment elevation acute coronary syndrome or ST-segment elevation myocardial infarction, with or without cardiogenic shock. In addition, we provide practical recommendations for revascularization in patients with high-risk multivessel disease to optimize their long-term clinical outcomes and identify areas requiring future clinical investigation.

Impact of Diabetes Control on Subclinical Atherosclerosis: Analysis from Coronary Computed Tomographic Angiography Registry

BACKGROUND

There are limited data on the impact of diabetes control on the risk of subclinical coronary atherosclerosis.

METHODS

We analyzed 6,434 consecutive asymptomatic individuals without previous history of coronary artery disease who underwent coronary computed tomographic angiography (CCTA) (mean age, 53.7±7.6 years and 4,694 men [73.0%]). The degree and extent of subclinical coronary atherosclerosis were assessed by CCTA, and ≥50% diameter stenosis was defined as significant. A cardiac event was defined as a composite of all-cause death, myocardial infarction, unstable angina, or coronary revascularization. Study participants were categorized as normal (n=5,319), controlled diabetes (glycosylated hemoglobin [HbA1c] <7%, n=747), or uncontrolled diabetes (HbA1c ≥7%, n=368), respectively.

RESULTS

Compared with normal individuals, there were no statistically significant differences in the risk of for any atherosclerotic plaque (odds ratio [OR], 1.16; 95% confidence interval [CI], 0.98 to 1.38; P=0.086) and significant coronary artery stenosis (OR, 1.08; 95% CI, 0.82 to 1.42; P=0.583) in controlled diabetic individuals. In contrast, uncontrolled diabetic individuals had consistently higher risks of any atherosclerotic plaque (OR, 2.16; 95% CI, 1.70 to 2.75; P<0.001) and significant coronary artery stenosis (OR, 3.34; 95% CI, 2.52 to 4.43; P<0.001) than normal individuals. During a follow-up of median 5.4 years, there was no significant difference in cardiac events between normal and controlled diabetic individuals (P=0.365). However, uncontrolled diabetes was associated with an increased risk of cardiac events compared with normal individuals (P<0.001) and controlled diabetic individuals (P=0.023).

CONCLUSION

Asymptomatic uncontrolled diabetes was associated with significant subclinical coronary atherosclerosis with subsequent high risk for cardiac events.

Association between perivascular inflammation and downstream myocardial perfusion in patients with suspected coronary artery disease

Aims

To investigate the association between pericoronary adipose tissue (PCAT) computed tomography (CT) attenuation derived from coronary computed tomography angiography (CTA) and coronary flow reserve (CFR) by positron emission tomography (PET) in patients with suspected coronary artery disease (CAD).

Methods and results

PCAT CT attenuation was measured in proximal segments of all major epicardial coronary vessels of 105 patients with suspected CAD. We evaluated the relationship between PCAT CT attenuation and other quantitative/qualitative CT-derived anatomic parameters with CFR by PET. Overall, the mean age was 60 ± 12 years and 93% had intermediate pre-test probability of obstructive CAD. Obstructive CAD (≥50% stenosis) was detected in 37 (35.2%) patients and impaired CFR (&lt;2.0) in 32 (30.5%) patients. On a per-vessel analysis (315 vessels), obstructive CAD, non-calcified plaque volume, and PCAT CT attenuation were independently associated with CFR. In patients with coronary calcium score (CCS) &lt;100, those with high-PCAT CT attenuation presented significantly lower CFR values than those with low-PCAT CT attenuation (2.47 ± 0.95 vs. 3.13 ± 0.89, P = 0.003). Among those without obstructive CAD, CFR was significantly lower in patients with high-PCAT CT attenuation (2.51 ± 0.95 vs. 3.02 ± 0.84, P = 0.021).

Conclusion

Coronary perivascular inflammation by CTA was independently associated with downstream myocardial perfusion by PET. In patients with low CCS or without obstructive CAD, CFR was lower in the presence of higher perivascular inflammation. PCAT CT attenuation might help identifying myocardial ischaemia particularly among patients who are traditionally considered non-high risk for future cardiovascular events.

Variation in Revascularization Practice and Outcomes in Asymptomatic Stable Ischemic Heart Disease

OBJECTIVES

The aims of this study were to assess variation in revascularization of asymptomatic patients with stable ischemic heart disease, identify the predictors of variation, and determine if it was associated with clinical outcomes.

BACKGROUND

Management of stable ischemic heart disease in asymptomatic patients with obstructive coronary artery disease is controversial, potentially leading to practice variation.

METHODS

A retrospective observational cohort study was performed using population-based data from Ontario, Canada, in patients with asymptomatic stable ischemic heart disease and obstructive coronary artery disease. The cohort was divided on the basis of treatment strategy: revascularization or medical therapy. Hospitals were allocated into tertiles of their revascularization ratio. Outcomes included death and nonfatal myocardial infarction. Hierarchical logistic regression was used to assess the predictors of revascularization, with median odds ratios used to quantify variation. Proportional hazards models were used to determine the association between management strategy and outcomes.

RESULTS

The cohort included 9,897 patients, 47% treated with medical therapy and 53% with revascularization. Between hospitals, 2-fold variation existed in the ratio of revascularized to medically treated patients. However, the variation across hospitals was not explained by patient, physician, or hospital factors (median odds ratio in null model: 1.25; median odds ratio in full model: 1.31). Revascularization was associated with a hazard ratio of 0.81 (95% confidence interval: 0.69 to 0.96) for death and a hazard ratio of 0.58 (95% confidence interval: 0.46 to 0.73) for myocardial infarction, with this benefit consistent across tertiles of revascularization ratio.

CONCLUSIONS

Wide variation was observed in revascularization practice that was not explained by known factors. Despite this variation, a clinical benefit was observed with revascularization that was consistent across hospitals.

Superior Risk Stratification With Coronary Computed Tomography Angiography Using a Comprehensive Atherosclerotic Risk Score

OBJECTIVES

This study was designed to assess the prognostic value of a new comprehensive coronary computed tomography angiography (CTA) score compared with the stenosis severity component of the Coronary Artery Disease-Reporting and Data System (CAD-RADS).

BACKGROUND

Current risk assessment with coronary CTA is mainly focused on maximal stenosis severity. Integration of plaque extent, location, and composition in a comprehensive model may improve risk stratification.

METHODS

A total of 2,134 patients with suspected but without known CAD were included. The predictive value of the comprehensive CTA score (ranging from 0 to 42 and divided into 3 groups: 0 to 5, 6 to 20, and >20) was compared with the CAD-RADS combined into 3 groups (0% to 30%, 30% to 70% and ≥70% stenosis). Its predictive performance was internally and externally validated (using the 5-year follow-up dataset of the CONFIRM [Coronary CT Angiography Evaluation for Clinical Outcomes: An International Multicenter Registry], n = 1,971).

RESULTS

The mean age of patients was 55 ± 13 years, mean follow-up 3.6 ± 2.8 years, and 130 events (myocardial infarction or death) occurred. The new, comprehensive CTA score showed strong and independent predictive value using the Cox proportional hazard analysis. A model including clinical variables plus comprehensive CTA score showed better discrimination of events compared with a model consisting of clinical variables plus CAD-RADS (0.768 vs. 0.742, p = 0.001). Also, the comprehensive CTA score correctly reclassified a significant proportion of patients compared with the CAD-RADS (net reclassification improvement 12.4%, p < 0.001). Good predictive accuracy was reproduced in the external validation cohort.

CONCLUSIONS

The new comprehensive CTA score provides better discrimination and reclassification of events compared with the CAD-RADS score based on stenosis severity only. The score retained similar prognostic accuracy when externally validated. Anatomic risk scores can be improved with the addition of extent, location, and compositional measures of atherosclerotic plaque. (Comprehensive CTA risk score calculator is available at: http://18.224.14.19/calcApp/).

Temporal Trends in Fractional Flow Reserve Use in Patients Undergoing Coronary Angiography: A Population-Based Study

Background

Invasive fractional flow reserve (FFR) has emerged as an important tool to identify a subset of patients in whom coronary revascularization may be beneficial. Our objective was to evaluate temporal trends in FFR use.

Methods

We identified all coronary angiograms in the CorHealth Ontario Cardiac Registry between the years 2010 and 2015. The primary and secondary outcomes were the age- and sex-adjusted monthly rate of FFR per 100,000 population and per 100 angiograms, respectively. Piecewise regression analyses were used to evaluate the temporal trends in FFR use for the entire cohort, and then stratified by indication (stable coronary artery disease [CAD]) vs acute coronary syndrome [ACS]).

Results

The study cohort included 379,688 angiograms, of which 122,571 were for stable CAD (32%) and 134,769 were for ACS (36%). Monthly age- and sex-adjusted FFR use rates increased significantly over the study period, from 0.4 to 2.3 per 100,000 people per month. The monthly FFR use rate per 100 angiograms increased from 0.9 to 4.9 per 100 angiograms per month; however, the proportion of positive FFR (< 0.8) results was relatively constant at 28%. There was a more dramatic increase in the use of FFR in the population with stable CAD (1.1 to 8.0 per 100 angiograms/month) compared with the population with ACS (0.6 to 4.5 per 100 angiograms/month).

Conclusions

There was a > 5-fold increase in the use of FFR in patients across Ontario, which was predominantly driven by use in stable CAD. Case selection for FFR use was relatively unchanged with approximately one-quarter of FFR cases being positive over time.

Hypertension Is an Independent Predictor of Multivessel Coronary Artery Disease in Young Adults with Acute Coronary Syndrome

Background

Risk factors of multivessel coronary artery disease (CAD) among young acute coronary syndrome (ACS) patients remain elusive now.

Methods

This retrospective study analyzed data from 187 consecutive young (age ≤45 years) ACS patients (75 STEMI, 30 NSTEMI, and 72 unstable angina) hospitalized in our hospital from January 2012 to December 2016. Thirty-six young male patients with normal coronary angiography (CAG) findings (no-CAD), who underwent CAG due to suspected chest pain in this period, served as control group. There were 83 patients with single-vessel disease (SVD) and 104 patients with multiple-vessel disease (MVD) among ACS patients. Patients were followed up for a mean of 267±124 days by clinical visit or telephone calls.

Results

All included patients were male. Prevalence of hypertension (57.2% vs. 30.6%, p=0.002) and smoking (70.6% vs. 52.8%, p=0.049) was significantly higher in ACS patients than in no-CAD patients. Prevalence of hypertension (72.1% vs. 38.6%, p<0.001) and body mass index (BMI) were significantly higher in MVD group than in SVD group. Multivariable analysis revealed that hypertension was an independent risk factor for MVD after adjustment for age, gender, BMI, smoking, family history of premature CAD, hyperlipidemia, left ventricular ejection fraction, and brain natriuretic peptide (odds ratio=3.71, 95% confidence interval=1.84-7.46, p<0.001). Rate of major adverse cardiovascular events (MACE) during follow-up (20.2% vs. 4.8%) was significantly higher in MVD group compared with SVD group.

Conclusions

Hypertension is an independent predictor of MVD and MVD is associated with increased MACE rate compared to SVD in young ACS patients during the short-term follow-up.

Diabetes and Subclinical Coronary Atherosclerosis

It is well known that diabetic patients have a high risk of cardiovascular events, and although there has been a tremendous effort to reduce these cardiovascular risks, the incidence of cardiovascular morbidity and mortality in diabetic patients remains high. Therefore, the early detection of coronary artery disease (CAD) is necessary in those diabetic patients who are at risk of cardiovascular events. Significant medical and radiological advancements, including coronary computed tomography angiography (CCTA), mean that it is now possible to investigate the characteristics of plaques, instead of solely evaluating the calcium level of the coronary artery. Recently, several studies reported that the prevalence of subclinical coronary atherosclerosis (SCA) is higher than expected, and this could impact on CAD progression in asymptomatic diabetic patients. In addition, several reports suggest the potential benefit of using CCTA for screening for SCA in asymptomatic diabetic patients, which might dramatically decrease the incidence of cardiovascular events. For these reasons, the medical interest in SCA in diabetic patients is increasing. In this article, we sought to review the results of studies on CAD in asymptomatic diabetic patients and discuss the clinical significance and possibility of using CCTA to screen for SCA.

Coronary revascularization vs. medical therapy following coronary-computed tomographic angiography in patients with low-, intermediate- and high-risk coronary artery disease: results from the CONFIRM long-term registry

Aims

To identify the effect of early revascularization on 5-year survival in patients with CAD diagnosed by coronary-computed tomographic angiography (CCTA).

Methods and results

We examined 5544 stable patients with suspected CAD undergoing CCTA who were followed a median of 5.5 years in a large international registry. Patients were categorized as having low-, intermediate-, or high-risk CAD based on CCTA findings. Two treatment groups were defined: early revascularization within 90 days of CCTA (n = 1171) and medical therapy (n = 4373). To account for the non-randomized referral to revascularization, we developed a propensity score by logistic regression. This score was incorporated into Cox proportional hazard models to calculate the effect of revascularization on all-cause mortality. Death occurred in 363 (6.6%) patients and was more frequent in medical therapy. In multivariable models, when compared with medical therapy, the mortality benefit of revascularization varied significantly over time and by CAD risk (P for interaction 0.04). In high-risk CAD, revascularization was significantly associated with lower mortality at 1 year (hazard ratio [HR] 0.22, 95% confidence interval [CI] 0.11–0.47) and 5 years (HR 0.31, 95% CI 0.18–0.54). For intermediate-risk CAD, revascularization was associated with reduced mortality at 1 year (HR 0.45, 95% CI 0.22–0.93) but not 5 years (HR 0.63, 95% CI 0.33–1.20). For low-risk CAD, there was no survival benefit at either time point.

Conclusions

Early revascularization was associated with reduced 1-year mortality in intermediate- and high-risk CAD detected by CCTA, but this association only persisted for 5-year mortality in high-risk CAD.

Elective Coronary Revascularization Procedures in Patients With Stable Coronary Artery Disease: Incidence, Determinants, and Outcome (From the CORONOR Study)

OBJECTIVES

The authors sought to describe the incidence, determinants, and outcome of elective coronary revascularization (ECR) in patients with stable coronary artery disease (CAD).

BACKGROUND

Observational data are lacking regarding the practice of ECR in patients with stable CAD receiving modern secondary prevention.

METHODS

The authors analyzed coronary revascularization procedures performed during a 5-year follow-up in 4,094 stable CAD outpatients included in the prospective multicenter CORONOR (Suivi d'une cohorte de patients COROnariens stables en région NORd-Pas-de-Calais) registry.

RESULTS

Secondary prevention medications were widely prescribed at inclusion (antiplatelet agents 96.4%, statins 92.2%, renin-angiotensin system antagonists 81.8%). A total of 481 patients underwent ≥1 coronary revascularization procedure (5-year cumulative incidences of 3.6% [0.7% per year] for acute revascularizations and 8.9% [1.8% per year] for ECR); there were 677 deaths during the same period. Seven baseline variables were independently associated with ECR: prior coronary stent implantation (p < 0.0001), absence of prior myocardial infarction (p < 0.0001), higher low-density lipoprotein cholesterol (p < 0.0001), lower age (p < 0.0001), multivessel CAD (p = 0.003), diabetes mellitus (p = 0.005), and absence of treatment with renin-angiotensin system antagonists (p = 0.020). Main indications for ECR were angina associated with a positive stress test (31%), silent ischemia (31%), and angina alone (25%). The use of ECR had no impact on the subsequent risk of death, myocardial infarction, or ischemic stroke (hazard ratio: 1.04; 95% confidence interval: 0.76 to 1.41).

CONCLUSIONS

These real-life data show that ECR is performed at a rate of 1.8% per year in stable CAD patients widely treated by secondary medical prevention. ECR procedures performed in patients without noninvasive stress tests are not rare. Having an ECR was not associated with the risk of ischemic adverse events.

Propensity Score-Based Methods in Comparative Effectiveness Research on Coronary Artery Disease

This review examines the conduct and reporting of observational studies using propensity score-based methods to compare coronary artery bypass grafting (CABG), percutaneous coronary intervention (PCI), or medical therapy for patients with coronary artery disease. A systematic selection process identified 48 studies: 20 addressing CABG versus PCI; 21 addressing bare-metal stents versus drug-eluting stents; 5 addressing CABG versus medical therapy; 1 addressing PCI versus medical therapy; and 1 addressing drug-eluting stents versus balloon angioplasty. Of 32 studies reporting information on variable selection, 7 relied exclusively on statistical criteria for the association of covariates with treatment, and 5 used such criteria to determine whether product or nonlinear terms should be included in the propensity score model. Twenty-five (52%) studies reported assessing covariate balance using the estimated propensity score, but only 1 described modifications to the propensity score model based on this assessment. The over 400 variables used in the 48 propensity score models were classified into 12 categories and 60 subcategories; only 17 subcategories were represented in at least half of the propensity score models. Overall, reporting of propensity score-based methods in observational studies comparing CABG, PCI, and medical therapy was incomplete; when adequately described, the methods used were often inconsistent with current methodological standards.

Evaluation of Atherosclerotic Plaque in Non-invasive Coronary Imaging

Coronary artery disease (CAD) is the leading cause of morbidity and mortality worldwide. Over the last decade coronary computed tomography angiography (CCTA) has gained wide acceptance as a reliable, cost-effective and non-invasive modality for diagnosis and prognostication of CAD. Use of CCTA is now expanding to characterization of plaque morphology and identification of vulnerable plaque. Additionally, CCTA is developing as a non-invasive modality to monitor plaque progression, which holds future potential in individualizing treatment. In this review, we discuss the role of CCTA in diagnosis and management of CAD. Additionally, we discuss the recent advancements and the potential clinical applications of CCTA in management of CAD.

Long-Term Prognostic Value of Coronary Computed Tomography Angiography

OPINION STATEMENT

Coronary CT angiography (CTA) is a highly accurate test for the diagnosis of coronary artery disease (CAD), with its use guided by numerous contemporary appropriate use criteria and clinical guidelines. Unique among non-invasive tests for CAD, coronary CTA provides direct visualization of coronary atherosclerosis for the assessment of angiographic stenosis, as well as validated measures of plaque vulnerability. Long-term studies now clearly demonstrate that the absence of CAD on coronary CTA identifies a patient that is at very low risk for future cardiovascular events. Conversely, the presence, location, and severity of CAD as measured on coronary CTA provide powerful prognostic information that is superior to traditional risk factors and other clinical variables. Observational studies and data obtained from clinical trials suggest that the anatomic information derived from coronary CTA significantly increases the utilization of statins and aspirin. Furthermore, these changes are associated with reductions in the risk for mortality, revascularizations, and incident myocardial infarctions among subjects with coronary atherosclerosis. As a result, current societal consensus statements have attempted to standardize coronary CTA reporting, to include incorporation of vulnerable plaque features and recommendations on the use of preventive therapies, such as statins, so to more consistently link important prognostic findings on coronary CTA to appropriate preventive and therapeutic interventions. Automated measures of total coronary plaque volume, machine learning, and CT-derived fractional flow reserve may further refine the prognostic accuracy of coronary CTA. Herein, we summarize recently published literature that reports the long-term (≥ 5 years of follow-up) prognostic usefulness of coronary CTA.

Downstream resource utilization following SPECT: Impact of age and gender

BACKGROUND

Previous studies have identified a downstream referral age and gender bias for invasive coronary anatomy evaluation after single-photon emission computed tomography myocardial perfusion imaging (SPECT MPI). The present study evaluates if such bias still persists despite advancements in SPECT MPI and angiography. We hypothesized that women and patients ≥80 years old are less likely to undergo invasive coronary angiography after adjusting for clinical and scan variables.

METHODS

Patients (n = 3824) who referred to a nuclear cardiology laboratory at a tertiary medical center were retrospectively identified. Regression analysis tested age (<55; 55-69; 70-79; ≥80 years) and gender as predictors of diagnostic angiogram at 90 days post-SPECT after adjustment for known CAD, CAD risk equivalent, SSS, SDS, and LVEF.

RESULTS

Younger patients were more likely to undergo an angiogram as compared to octogenarians (77% more likely if <55 years old, 69% if 55-69 years old, and 52% if 70-79 years old). No effect was found for gender.

CONCLUSIONS

Older patients were less likely to be referred for angiogram as compared to their younger counterparts. Further study is needed to determine which factors guide this decision-making process in older adults and the influence of these factors on the referral bias.

Testing in Patients With Stable Coronary Artery Disease - The Debate Continues

The major guidelines on stable coronary artery disease recommend revascularizing patients with large areas of myocardium at risk. The algorithms on how to prove that such high risk is present differ considerably. The opinions on the use of coronary CT (calcium scoring and angiography) vary widely. This review aims to summarize the recommendations of the major guidelines, commenting on differences between the guidelines and discussing whether extending the role of coronary CT angiography should be considered in the light of new CT data.

Coronary Computed Tomographic Angiography Does Not Accurately Predict the Need of Coronary Revascularization in Patients with Stable Angina

PURPOSE

To evaluate the ability of coronary computed tomographic angiography (CCTA) to predict the need of coronary revascularization in symptomatic patients with stable angina who were referred to a cardiac catheterization laboratory for coronary revascularization.

MATERIALS AND METHODS

Pre-angiography CCTA findings were analyzed in 1846 consecutive symptomatic patients with stable angina, who were referred to a cardiac catheterization laboratory at six hospitals and were potential candidates for coronary revascularization between July 2011 and December 2013. The number of patients requiring revascularization was determined based on the severity of coronary stenosis as assessed by CCTA. This was compared to the actual number of revascularization procedures performed in the cardiac catheterization laboratory.

RESULTS

Based on CCTA findings, coronary revascularization was indicated in 877 (48%) and not indicated in 969 (52%) patients. Of the 877 patients indicated for revascularization by CCTA, only 600 (68%) underwent the procedure, whereas 285 (29%) of the 969 patients not indicated for revascularization, as assessed by CCTA, underwent the procedure. When the coronary arteries were divided into 15 segments using the American Heart Association coronary tree model, the sensitivity, specificity, positive predictive value, and negative predictive value of CCTA for therapeutic decision making on a per-segment analysis were 42%, 96%, 40%, and 96%, respectively.

CONCLUSION

CCTA-based assessment of coronary stenosis severity does not sufficiently differentiate between coronary segments requiring revascularization versus those not requiring revascularization. Conventional coronary angiography should be considered to determine the need of revascularization in symptomatic patients with stable angina.

Clinical Outcomes After Evaluation of Stable Chest Pain by Coronary Computed Tomographic Angiography Versus Usual Care: A Meta-Analysis

BACKGROUND

Limited data exist on how noninvasive testing options compare for evaluating patients with suspected stable coronary artery disease. In this study, we have performed a meta-analysis of randomized controlled trials comparing the use of coronary computed tomographic angiography (CTA) with usual care.

METHODS AND RESULTS

We systematically searched databases for randomized clinical trials comparing coronary CTA with usual care for the evaluation of stable chest pain with follow-up for cardiovascular outcomes. The primary outcomes were myocardial infarction and all-cause mortality. We identified 4 randomized clinical trials, including a total of 7403 patients undergoing coronary CTA and 7414 patients undergoing usual care with various functional testing approaches. When compared with usual care, the use of coronary CTA was associated with a significant reduction in the annual rate of myocardial infarction (rate ratio, 0.69; 95% confidence interval, 0.49-0.98; P=0.038), but no difference was found in all-cause mortality. There was a trend toward more invasive coronary angiographies among patients undergoing coronary CTA (odds ratio, 1.33; 95% confidence interval, 0.95-1.84; P=0.09) and higher use of coronary revascularizations (odds ratio, 1.77; 95% confidence interval, 1.14-2.75). Significant heterogeneity for invasive coronary angiography and revascularization was noted, which was attributable to the Scottish Computed Tomography of the HEART (SCOT-HEART) study. We found no difference in the rate of admission for cardiac chest pain (rate ratio, 1.21; 95% confidence interval, 0.95-1.54).

CONCLUSIONS

In comparison to usual care, an initial investigation of suspected stable coronary artery disease using coronary CTA resulted in a significant reduction in myocardial infarction, an increased incidence of coronary revascularization, and no effect in all-cause mortality. Future studies should further define whether the potential reduction in myocardial infarction identified justifies the increased resource utilization associated with coronary CTA.

[Recommendations of the ESC guidelines regarding cardiovascular imaging]

Cardiac imaging plays a key role in the diagnosis and risk stratification in the ESC guidelines for the management of patients with stable coronary artery disease. Demonstration of myocardial ischaemia guides the decision which further diagnostic and therapeutic strategy should be followed in these patients. One should, however, not forget that there are no randomised studies supporting this type of management. In patients with a low pretest probability coronary CT angiography is the optimal tool to exclude coronary artery stenoses rapidly and effectively. In the near future, however, better data is needed showing how much cardiac imaging is really necessary and how cost-effective it is in patients with stable coronary artery disease.

Predictors of high-risk coronary artery disease in subjects with normal SPECT myocardial perfusion imaging

BACKGROUND

While uncommon, normal stress SPECT myocardial perfusion imaging (MPI) can be seen in patients with high-risk coronary artery disease (CAD) by invasive coronary angiography (ICA).The predictors of high-risk CAD in patients with normal SPECT-MPI have not been described.

METHODS

We studied 580 patients (age 64 ± 12 years, 49% men) without known CAD who underwent stress-gated SPECT-MPI [exercise (41%) or vasodilator (59%)] <2 months before ICA and had summed stress score (SSS) <4. High-risk CAD was defined as 3 vessels with ≥70% stenosis, 2 vessels with ≥70% stenosis including proximal left anterior descending, or left main with ≥50% stenosis. Obstructive non-high-risk CAD was defined by the presence of a ≥70% stenosis but without having other high-risk criteria. Tenfold cross-validated receiver operating characteristic (ROC) estimates were obtained to assess the predictors of high-risk CAD.

RESULTS

Forty-two subjects (7.2%) had high-risk CAD and 168 (29.0%) had obstructive non-high-risk CAD. Variables associated with high-risk CAD were pretest probability of CAD ≥66% (Odds ratio [OR] 3.63, 95% CI 1.6-8.3, P = .002), SSS > 0 (OR 7.46, 95% CI 2.6-21.1, P < 0.001), and abnormal TID (OR 2.16, 95% CI 1.0-4.5, P = 0.044). When substituted for TID, EF change was also predictive of high-risk CAD (OR 0.93, 95% CI 0.9-1.0, P = 0.023). The prevalence of high-risk CAD increased as the number of these predictors increased. In a sub-analysis of patients in whom quantitative total perfusion deficit (TPD) was available, TPD > 0 was also a predictor of high-risk CAD (OR 6.01, 95% CI 1.5-22.2, P = 0.011).

CONCLUSION

Several clinical, stress, and SPECT-MPI findings are associated high-risk CAD among patients with normal SPECT-MPI. Consideration of these factors may improve the overall assessment of the likelihood of high-risk CAD in patients undergoing stress SPECT-MPI.

Medical Therapy With Versus Without Revascularization in Stable Patients With Moderate and Severe Ischemia: The Case for Community Equipoise

All patients with stable ischemic heart disease (SIHD) should be managed with guideline-directed medical therapy (GDMT), which reduces progression of atherosclerosis and prevents coronary thrombosis. Revascularization is also indicated in patients with SIHD and progressive or refractory symptoms, despite medical management. Whether a strategy of routine revascularization (with percutaneous coronary intervention or coronary artery bypass graft surgery as appropriate) plus GDMT reduces rates of death or myocardial infarction, or improves quality of life compared to an initial approach of GDMT alone in patients with substantial ischemia is uncertain. Opinions run strongly on both sides, and evidence may be used to support either approach. Careful review of the data demonstrates the limitations of our current knowledge, resulting in a state of community equipoise. The ongoing ISCHEMIA trial (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches) is being performed to determine the optimal approach to managing patients with SIHD, moderate-to-severe ischemia, and symptoms that can be controlled medically. (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches [ISCHEMIA]; NCT01471522).

Fasting but not changes of plasma metabolome during oral glucose tolerance tests improves the diagnosis of severe coronary arterial stenosis

BACKGROUND

Noninvasive stress tests for the diagnosis of significant coronary arterial stenosis requiring intervention are not perfect. We investigated whether plasma metabolome during the oral glucose tolerance test (OGTT) can improve the diagnosis.

METHODS

A total of 117 subjects with positive stress test results who received coronary angiography were recruited. After excluding subjects with a history of myocardial infarction and subjects who did not receive OGTT, the 18 subjects without significant stenosis were selected as controls. Another 18 age- and sex-matched subjects with significant stenosis were selected as cases. Plasma metabolome from samples obtained in fasting, 30 and 120 min after OGTT was measured using liquid chromatography combined with time-of-flight mass spectrometry.

RESULTS

We found five metabolites which can identify patients with significant stenosis independent to clinical risk factors, including diabetes, hypertension, hypercholesterolaemia, smoking and history of percutaneous coronary intervention (all P < 0·05). The area under the receiver operating characteristic (AUROC) curve of these metabolites was 0·799-0·818 at fasting and 30 min after OGTT. The addition of metabolites to clinical factors increases the AUROC (0·616, 95%CI 0·429-0·803 for model with clinical factors only; 0·824, 95%CI 0·689-0·959 for model with four metabolites and clinical factors). The changes of plasma metabolite levels during OGTT did not significantly improve the diagnostic performance.

CONCLUSIONS

Fasting plasma metabolome, but not change of plasma metabolome during OGTT, can improve the diagnosis of significant stenosis in patients with positive noninvasive stress test results.

Coronary Computed Tomography Angiography Versus Radionuclide Myocardial Perfusion Imaging in Patients With Chest Pain Admitted to Telemetry: A Randomized Trial

BACKGROUND

The role of coronary computed tomography angiography (CCTA) in the management of symptomatic patients suspected of having coronary artery disease is expanding. However, prospective intermediate-term outcomes are lacking.

OBJECTIVE

To compare CCTA with conventional noninvasive testing.

DESIGN

Randomized, controlled comparative effectiveness trial. (ClinicalTrials.gov: NCT00705458).

SETTING

Telemetry-monitored wards of an inner-city medical center.

PATIENTS

400 patients with acute chest pain (mean age, 57 years); 63% women; 54% Hispanic and 37% African-American; and low socioeconomic status.

INTERVENTION

CCTA or radionuclide stress myocardial perfusion imaging (MPI).

MEASUREMENTS

The primary outcome was cardiac catheterization not leading to revascularization within 1 year. Secondary outcomes included length of stay, resource utilization, and patient experience. Safety outcomes included death, major cardiovascular events, and radiation exposure.

RESULTS

Thirty (15%) patients who had CCTA and 32 (16%) who had MPI underwent cardiac catheterization within 1 year. Fifteen (7.5%) and 20 (10%) of these patients, respectively, did not undergo revascularization (difference, -2.5 percentage points [95% CI, -8.6 to 3.5 percentage points]; hazard ratio, 0.77 [CI, 0.40 to 1.49]; P = 0.44). Median length of stay was 28.9 hours for the CCTA group and 30.4 hours for the MPI group (P = 0.057). Median follow-up was 40.4 months. For the CCTA and MPI groups, the incidence of death (0.5% versus 3%; P = 0.12), nonfatal cardiovascular events (4.5% versus 4.5%), rehospitalization (43% versus 49%), emergency department visit (63% versus 58%), and outpatient cardiology visit (23% versus 21%) did not differ. Long-term, all-cause radiation exposure was lower for the CCTA group (24 versus 29 mSv; P < 0.001). More patients in the CCTA group graded their experience favorably (P = 0.001) and would undergo the examination again (P = 0.003).

LIMITATION

This was a single-site study, and the primary outcome depended on clinical management decisions.

CONCLUSION

The CCTA and MPI groups did not significantly differ in outcomes or resource utilization over 40 months. Compared with MPI, CCTA was associated with less radiation exposure and with a more positive patient experience.

PRIMARY FUNDING SOURCE

American Heart Association.

Comparison of Coronary Computed Tomographic Angiographic Findings in Asymptomatic Subjects With Versus Without Diabetes Mellitus

There are limited data on the impact of diabetes mellitus (DM) on the risk of subclinical atherosclerosis. Therefore, we sought to investigate the impact of DM on the risk of subclinical atherosclerosis in asymptomatic subjects. We analyzed 2,034 propensity score-matched asymptomatic subjects who underwent coronary computed tomographic angiography (mean age 55.9 ± 8.2 years; men 1,725 [84.8%]). Coronary artery calcium score, degree and extent of coronary artery disease (CAD), and clinical outcomes were assessed. High-risk CAD was defined as at least 2-vessel coronary disease with proximal left anterior descending artery involvement, 3-vessel disease, or left main disease. Compared with subjects without DM, those matched with DM had higher coronary artery calcium score (89.9 ± 240.4 vs 62.8 ± 179.5, p = 0.004) and more significant CAD (≥50% diameter stenosis, 15.2% vs 10.2%, p = 0.001), largely in the form of 1-vessel disease (10.8% vs 7.3%, p = 0.007). However, there were no significant differences between matched pairs in significant CAD in the left main or proximal left anterior descending artery (5.3% vs 3.8%, p = 0.138), multivessel disease (4.4% vs 2.9%, p = 0.101), and high-risk CAD (4.3% vs 2.7%, p = 0.058). During the follow-up period (median 21.8, interquartile range 15.2 to 33.4 months), there was no significant difference in the composite of all-cause death, myocardial infarction, acute coronary syndrome, and coronary revascularization between 2 groups (hazard ratio 1.438, 95% confidence interval 0.844 to 2.449, p = 0.181). In asymptomatic subjects, those matched with DM have more subclinical atherosclerosis, mainly confined to non-high-risk CAD, than those matched without DM, and there are no differences in high-risk CAD and clinical outcomes.

Diagnostic and Therapeutic Usefulness of Coronary Computed Tomography Angiography in Out-Clinic Patients Referred for Chest Pain

Coronary computed tomography angiography (CCTA) is widely used to exclude coronary artery disease (CAD) in patients with low-to-intermediate pretest probability (PTP) of obstructive CAD. The aim of our study was to investigate the reclassification by CCTA and the implications of CCTA results on management because limited studies exist on these subjects; 1,560 patients with chest pain without a history of CAD and with low or intermediate PTP of CAD referred for CCTA from the out-patient clinic were prospectively included. PTP was defined by the Duke Clinical Score as either low (<15%), low-intermediate (15% to 50%), or high-intermediate (50% to 85%). Distribution of CCTA results among the categories of PTP of CAD and the influence of CCTA results on management were analyzed. CCTA revealed obstructive CAD in 7%, 15%, and 23% of cases, in patients with low, low-intermediate, and high-intermediate PTP, respectively; 855 of 1,031 patients (83%) with intermediate PTP of CAD showed no obstructive CAD on CCTA and were consequently reclassified. Management changes after CCTA occurred in 689 patients (44%). In 633 patients (41%), medication was altered and 135 (9%) were referred for invasive coronary angiography. Treatment with statin was initiated in 442 (28%) and stopped in 71 patients (5%). Aspirin was initiated in 192 (12%) and stopped in 139 patients (9%). In conclusion, in a routine clinical cohort, CCTA resulted in reclassification in most patients. Furthermore, our study suggests that the Duke Clinical Score overestimates the probability of obstructive CAD compared with CCTA findings. Finally, CCTA results have implications on patient management, with medication changes in 41% of patients.

Finding the Gatekeeper to the Cardiac Catheterization Laboratory: Coronary CT Angiography or Stress Testing?

Functional capacity is a robust predictor of clinical outcomes, and stress testing is used in current practice paradigms to guide referral to invasive coronary angiography. However, invasive coronary angiography is driven by ongoing symptoms, as well as risk of adverse outcomes. The limitations of current functional testing-based paradigms might be avoided by using coronary computed tomographic angiography (CCTA) for exclusion of obstructive coronary artery disease. The growth of CCTA has been supported by comparative prognostic evidence with CCTA and functional testing, as well as radiation dose reduction. Use of CCTA for physiological evaluation of coronary lesion-specific ischemia may facilitate evaluation of moderate stenoses, designation of the culprit lesion, and prediction of benefit from revascularization. The potential of CCTA to serve as an effective gatekeeper to invasive coronary angiography will depend, in part, on the adoption of these new developments, as well as definition of the benefit of detecting high-risk plaque for guiding the management of selected patients.

Management of Coronary Artery Calcium and Coronary CTA Findings

Coronary artery calcium (CAC) testing and coronary computed tomography angiography (CTA) have significant data supporting their ability to identify coronary artery disease (CAD) and classify patient risk for atherosclerotic cardiovascular disease (ASCVD). Evidence regarding CAC use for screening has established an excellent prognosis in patients with no detectable CAC, and the ability to risk re-classify the majority of asymptomatic patients considered intermediate risk by traditional risk scores. While data regarding the ideal management of CAC findings are limited, evidence supports statin consideration in patients with CAC > 0 and individualized aspirin therapy accounting for CAD risk factors, CAC severity, and factors which increase a patient's risk of bleeding. In patients with stable or acute symptoms undergoing coronary CTA, a normal CTA predicts excellent prognosis, allowing reassurance and disposition without further testing. When CTA identifies nonobstructive CAD (<50 % stenosis), observational data support consideration of statin use/intensification in patients with extensive plaque (at least four coronary segments involved) and patients with high-risk plaque features. In patients with both nonobstructive and obstructive CAD, multiple studies have now demonstrated an ability of CTA to guide management and improve CAD risk factor control. Still, significant under-treatment of cardiovascular risk factors and high-risk image findings remain, among concerns that CTA may increase invasive angiography and revascularization. To fully realize the impact of atherosclerosis imaging for ASCVD prevention, patient engagement in lifestyle changes and the modification of ASCVD risk factors remain the foundation of care. This review provides an overview of available data and recommendations in the management of CAC and CTA findings.

Risk score model for the assessment of coronary artery disease in asymptomatic patients with type 2 diabetes

No model has been developed to predict significant coronary artery disease (CAD) on coronary computed tomographic angiography (CCTA) in asymptomatic type 2 diabetes. Therefore, we sought to develop a model for the prediction of significant CAD on CCTA in these patients. We analyzed 607 asymptomatic patients with type 2 diabetes who underwent CCTA. The cardiac event was defined as a composite of cardiac death, nonfatal myocardial infarction, acute coronary syndrome, and coronary revascularization. Significant CAD (diameter stenosis ≥50%) in at least one coronary artery on CCTA was observed in 188 (31.0%). During the follow-up period (median 4.3 [interquartile range, 3.7-4.8] years), 71 patients had 83 cardiac events. Clinical risk factors for significant CAD were age, male gender, duration of diabetes, hypertension, current smoking, family history of premature CAD, previous history of stroke, ratio of total cholesterol to high-density lipoprotein cholesterol, and neuropathy. Using these variables, we formulated a risk score model, and the scores ranged from 0 to 17 (area under the curve = 0.727, 95% confidence interval = 0.714-0.739, P < 0.001). Patients were categorized into low (≤3), intermediate (4-6), or high (≥7) risk group. There were significant differences between the risk groups in the probability of significant CAD (12.6% vs 29.4% vs 57.7%, P for all < 0.001) and 5-year cardiac event-free survival rate (96.6% ± 1.5% vs 88.9% ± 1.8% vs 73.8% ± 4.1%, log-rank P for trend < 0.001). This model predicts significant CAD on CCTA and has the potential to identify asymptomatic type 2 diabetes with high risk.