Prevalence Of Obstructive Coronary Artery Disease Research Articles

Long-term prognostic impact of fasting plasma glucose and myocardial flow reserve beyond other risk factors and heart disease phenotypes

Abstract Background Cardiometabolic risk factors, including high fasting plasma glucose (hFPG), are emerging determinants of residual mortality risk in patients with coronary artery disease (CAD) or heart failure (HF). Coronary microvascular dysfunction, encompassing a broad spectrum of traditional and emerging risk factors, might be a comprehensive risk predictor in these patients. Purpose To assess whether hFPG and global myocardial blood flow (MBF) reserve measured by positron emission tomography (PET), expressing global coronary function, may predict long-term prognosis beyond other risk factors and the presence of obstructive CAD or left ventricular (LV) dysfunction associated with HF. Methods Among 281 consecutive patients undergoing cardiac PET/CT because of stable chest pain or dyspnea we retrospectively collected long-term follow-up data in 103 patients (mean age 61±10 years, 74 males) in whom MBF measurements, coronary angiography and clinical data were available. Disease phenotypes included obstructive CAD (35%), LV dysfunction without obstructive CAD (43%) or none (22%). Results The mean age was 61±10 years (74 males, 72%). Among CVD risk factors, high LDL-cholesterol (hypercholesterolemia under treatment or LDL-C> 130 mg/dL) was present in 72%, high systemic blood pressure (hypertension under treatment or SBP>130/85 mmHg) in 51%, smoking habits in 49%, obesity (BMI>30 Kg/m2) in 22%, type 2 diabetes under treatment in 17%, low HDL-cholesterol (HDL-C< 40 mg/dL in males and <50 mg/dL in females) in 51%, high triglycerides (TG>150 mg/dL) in 27% and high fasting plasma glucose (FPG>100 mg/dL) in 33%. Global MBF reserve was <2 in 68% of patients. In a median follow-up of 10.9 years (7.8-13.9 IQR), 39 patients (37.8%) died (13.6% cardiac death). At multivariable Cox analyses including all risk factors and MBF reserve, age (HR 1.06, 95% CI 1.02-1.11), high FPG (HR 2.28, 95% CI 1.09-4.79) and depressed MBF reserve (HR 4.79, 95% CI 2.14-10.69) were the only independent predictors of death (Global χ2 36.74, P=0.0001). When disease phenotypes were added to the model, age (HR 1.07, 95% CI 1.02-1.12), high FPG (HR 2.18, 95% CI 1.02-4.63) and depressed MBF reserve (HR 4.47, 95% CI 1.96-10.18) remained independent predictors of death (Global χ2 37.41, P=0.0004) (Figure 1). Figure 2 plots the observed all cause death rate in patients with different disease phenotypes stratified for absence/presence of high FPG or MBF reserve <2. Death rate progressively increases according to disease phenotypes and is significantly associated with high FPG (P=0.049) or impaired MBF reserve (P=0.012) in each patient group. Conclusions These results suggest a strong long-term prognostic role of high FPG and depressed MBF reserve in a selected high-risk population of patients with high prevalence of obstructive CAD or HF.Figure 1 Figure 2

ClinicAl verSus algorIthmic predictioN of Obstructive Coronary Artery Disease - the CASINO study

Abstract Background The estimation of pretest probability (PTP) is a key step when evaluating patients with suspected coronary artery disease (CAD). Current European guidelines recommend using an algorithm based on age, sex, and symptom typicality. However, many cardiologists do not regularly use this method, relying instead on overall clinical impression. The aim of this study was to compare clinical and algorithmic prediction of obstructive CAD in a set of symptomatic patients with suspected chronic coronary syndrome (CCS). Methods In this survey study, 10 cardiologists from were asked to estimate the probability of obstructive CAD (on a scale of 1-99% and without the aid of any score or algorithm) for 120 anonymized clinical vignettes of outpatients who underwent diagnostic workup for suspected CCS. The provided information included age, sex, symptom description, cardiovascular risk factors, and know comorbidities. Whenever non-invasive tests had been performed, physicians were also asked to estimate the probability of obstructive CAD after knowing that results. Obstructive CAD was defined as diameter stenosis ≥50% confirmed by invasive coronary angiography. Results Among the 120 included patients (62 women, mean age 61±10 years), symptoms consisted of chest pain in 104 and dyspnea in the remainder. The median PTP of obstructive CAD was 15% (IQR 10-25%) according to the ESC algorithm, and 30% (IQR 15-50%) according to cardiologists’ estimates (p<0.001). The observed prevalence of obstructive CAD was 20% (n=24), yielding suitable calibration for the ESC model (predicted vs. observed p=0.631), and significant overestimation for clinicians’ assessments (predicted vs. observed p=0.014) – Figure 1A. Despite using the same data, cardiologists’ PTP estimates varied widely within the same patients (mean inter-observer coefficient of variation 56%±22%). In a subset of 29 patients whose PTP was appraised twice by the same physicians, the mean absolute difference between assessments (intra-observer variability) was 22%±8%. The ESC algorithm showed fair discriminative power to identify patients with obstructive CAD (C-statistic 0.68, 95% CI 0.58-0.79, p=0.005), whereas the C-statistic for clinicians ranged from 0.53 to 0.72 (average 0.62±0.05, p values for comparisons 0.001-0.677) – Fig 1B. In the subset of 70 patients with prior non-invasive tests, clinicians significantly changed their predictions after knowing test results (mean absolute difference 22%±12%, p<0.001), improving their discriminative power significantly (mean change in C-statistic of 0.08±0.09, p=0.020). Conclusion Clinicians’ assessments of PTP in symptomatic patients display high inter- and intra-observer variability, and tend to overestimate the likelihood of obstructive CAD. Despite using more clinical data, cardiologists fail to outperform the ESC algorithm. The systematic use of this tool should be promoted in order to improve disease prediction and guide non-invasive testing.

Long-term prognostic impact of fasting plasma glucose and myocardial flow reserve beyond other risk factors and heart disease phenotypes.

Cardiometabolic risk factors, including high fasting plasma glucose (hFPG), are emerging prognostic determinants in patients with coronary artery disease (CAD) or heart failure (HF). Coronary microvascular dysfunction might be a comprehensive risk predictor in these patients. The purpose of this study was to assess whether hFPG and global myocardial blood flow (MBF) reserve measured by positron emission tomography (PET), expressing global coronary function, predict long-term prognosis beyond other risk factors and presence of obstructive CAD or left ventricular (LV) dysfunction associated with HF. We retrospectively collected long-term follow-up data in 103 patients (mean age 61 ± 10 years, 74 males) with stable chest pain or dyspnoea who underwent cardiac PET/computerized tomography and coronary angiography. Disease phenotypes included obstructive CAD (35%), LV dysfunction without obstructive CAD (43%), or none (22%). At multivariable logistic regression analysis, MBF reserve lower than the median value (OR 1.8, 95% CI 1.5-2.2) was significantly associated with male gender (OR 3.45, 95% CI 1.21-9.83) and hFPG (OR 3.87, 95% CI 1.17-12.84) among all risk factors. In a median follow-up of 10.9 years (interquartile range 7.8-13.9), 39 patients (37.8%) died (13.6% cardiac death). At multivariable Cox analyses including all risk factors and disease phenotypes, age (HR 1.07, 95% CI 1.02-1.12), hFPG (HR 2.18, 95% CI 1.02-4.63), and depressed MBF reserve (HR 4.47, 95% CI 1.96-10.18) were independent predictors of death (global χ 2 37.41, P = 0.0004). These results suggest a strong long-term prognostic role of hFPG and depressed MBF reserve in a high-risk population of patients with a high prevalence of obstructive CAD or HF.

Subclinical Coronary Artery Disease in Patients with Idiopathic Inflammatory Myopathy: An Evaluation by CT Coronary Angiography

Idiopathic inflammatory myopathy (IIM) poses elevated risk of cardiovascular event and mortality, similar to other autoimmune rheumatic diseases. We conducted a cross-sectional study to examine the prevalence and risk factor of subclinical coronary artery disease (CAD) in patients with IIM, using CT coronary angiogram (CTCA). The prevalence of obstructive CAD and CAD in IIM (13.3% and 66.7%, respectively) were significantly higher than age and sex-matched controls (0% and 30%, respectively, both [Formula: see text]). Diabetes mellitus and calcium calcification score [Formula: see text] units were found to be the independent predictors of obstructive CAD. Screening of high-risk patients with aggressive treatment of cardiovascular risk factors should be considered in managing IIM patients.

Relationship between peri-coronary inflammation and coronary vascular function in patients with suspected coronary artery disease.

In this study, we aim to investigate the relationship between the attenuation of peri-coronary adipose tissue (PCAT) in patients with suspected coronary artery disease (CAD) and the assessment of coronary vascular functions using coronary flow reserve (CFR). We included 364 patients who underwent 13N-NH3 positron emission tomography/computed tomography and coronary computed tomography angiography (CCTA). We determined the relationship between fat attenuation index (FAI), PCAT volume, and other qualitative CT-derived anatomic parameters with CFR. We detected a decrease in CFR (<2.5) in 206 (57%) patients. At the patient level, those with reduced CFR showed a significantly higher prevalence of diffused atherosclerosis (41% vs. 23%; P < 0.001) and higher FAI (-75.5 HU vs. -77.1 HU; P = 0.014). In patients without obstructive CAD, FAI was significantly higher in those with reduced CFR (-75.5 HU vs. -77.7 HU, P = 0.026). On the vessel level, 1,092 vessels were analyzed, and 642 (59%) exhibited reduced CFR. The vessels with reduced CFR presented a significantly higher prevalence of obstructive CAD (37% vs. 26%; P < 0.001), diffused atherosclerosis (22% vs. 11%; P < 0.001), low-attenuation plaque (6% vs. 3%; P = 0.030), and positive remodeling (7% vs. 2%; P = 0.001). FAI was higher in vessels with reduced CFR (-80.8 HU vs. -81.8 HU; P = 0.045) than in normal CFR. In the patient-level analysis, obstructive CAD, diffused atherosclerosis, and FAI were independently linked with CFR. FAI was still associated with global CFR after adjusting for traditional risk factors (age, hypertension, diabetes, hyperlipidemia, and smoking). FAI remained independently associated with reduced CFR in patients without obstructive CAD. Coronary perivascular inflammation evaluated by CCTA was independently associated with coronary vascular function. In patients without obstructive CAD, FAI was higher in the presence of reduced CFR. Altogether, FAI can help reveal microcirculatory damage in patients who do not exhibit epicardial artery stenosis.

Age- and sex-based heterogeneity in coronary artery plaque presence and burden in familial hypercholesterolemia: A multi-national study

ObjectivesIndividuals with familial hypercholesterolemia (FH) are at an increased risk for coronary artery disease (CAD). While prior research has shown variability in coronary artery calcification (CAC) among those with FH, studies with small sample sizes and single-center recruitment have been limited in their ability to characterize CAC and plaque burden in subgroups based on age and sex. Understanding the spectrum of atherosclerosis may result in personalized risk assessment and tailored allocation of costly add-on, non-statin lipid-lowering therapies. We aimed to characterize the presence and burden of CAC and coronary plaque on computed tomography angiography (CTA) across age- and sex-stratified subgroups of individuals with FH who were without CAD at baseline. MethodsWe pooled 1,011 patients from six cohorts across Brazil, France, the Netherlands, Spain, and Australia. Our main measures of subclinical atherosclerosis included CAC ranges (i.e., 0, 1–100, 101–400, >400) and CTA-derived plaque burden (i.e., no plaque, non-obstructive CAD, obstructive CAD). ResultsNinety-five percent of individuals with FH (mean age: 48 years; 54% female; treated LDL-C: 154 mg/dL) had a molecular diagnosis and 899 (89%) were on statin therapy. Overall, 423 (42%) had CAC=0, 329 (33%) had CAC 1–100, 160 (16%) had CAC 101–400, and 99 (10%) had CAC >400. Compared to males, female patients were more likely to have CAC=0 (48% [n = 262] vs 35% [n = 161]) and no plaque on CTA (39% [n = 215] vs 26% [n = 120]). Among patients with CAC=0, 85 (20%) had non-obstructive CAD. Females also had a lower prevalence of obstructive CAD in CAC 1–100 (8% [n = 15] vs 18% [n = 26]), CAC 101–400 (32% [n = 22] vs 40% [n = 36]), and CAC >400 (52% [n = 16] vs 65% [n = 44]). Female patients aged 50–59 years were less likely to have obstructive CAD in CAC >400 (55% [n = 6] vs 70% [n = 19]). ConclusionIn this large, multi-national study, we found substantial age- and sex-based heterogeneity in CAC and plaque burden in a cohort of predominantly statin-treated individuals with FH, with evidence for a less pronounced increase in atherosclerosis among female patients. Future studies should examine the predictors of resilience to and long-term implications of the differential burden of subclinical coronary atherosclerosis in this higher risk population.

Influence of socioeconomic status on the presence of obstructive coronary artery disease and cardiovascular outcomes in patients undergoing invasive coronary angiography

Abstract Background Although it has been documented that low socioeconomic status (SES) is associated with increased risk of mortality and cardiovascular disease (CVD), this issue has not been addressed in patients at high CVD risk. This study was performed to investigate the association of the patient’s SES with the presence of obstructive coronary artery disease (CAD) and long-term cardiovascular outcomes who undergo invasive coronary angiography (ICA). Methods A total of 9,530 patients who underwent ICA for the evaluation and treatment of CAD (66.0 ± 12.3 years and 60.2% male) were retrospectively reviewed. The patients were divided into two groups according to the health insurance type: those with low SES who had the Medical aid program (Medical aid beneficiary [MAB] group; n = 1,436) and those with high SES who had the National Health Insurance program (National Health Insurance beneficiary [NHIB] group; n = 8,094). The primary outcome was a composite of cardiac death, acute myocardial infarction, coronary revascularization, and ischemic stroke. Results Of the study patients, 1,436 (15.1%) were in the MAB group. The prevalence of cardiovascular risk factors was higher in the MAB group compared to the NHIB group. However, the prevalence of obstructive CAD was similar between the two groups (62.8% vs. 64.2%; p = 0.306). During a median follow-up period of 3.5 years (interquartile range, 1.0-5.9 years), the incidence of the composite cardiovascular event was significantly higher in the MAB group than in the NHIB group (20.2% vs. 16.2%, p &amp;lt; 0.001). In multivariable Cox regression analysis, compared to the NHIB group, the MAB group was independently associated with worse clinical outcomes even after controlling for potential confounders (adjusted odds ratio, 1.28; 95% confidence interval, 1.07-1.54; p = 0.006). Conclusions Although CAD prevalence was similar, MABs showed an increased risk of composite cardiovascular events than NHIBs in Korean adults undergoing ICA. This provides additional evidence for the association between low SES and an increased risk of CVD, even in high-risk subjects.

The incremental value of coronary artery calcium in predicting obstructive coronary artery disease in a symptomatic mixed Asian cohort: external validation of RF-CL and CACS-CL

Abstract Background Estimating the pre-test probability (PTP) of coronary artery disease (CAD) is an essential step in the evaluation of patients with stable chest pain. Risk factor-weighted clinical likelihood (RF-CL) and coronary artery calcium score-weighted clinical likelihood (CACS-CL) are two simple models recently proposed to estimate the probability of obstructive CAD. However, these tools were predominantly developed and validated on Western populations. There is limited evidence of their predictive value in Asian populations. Purpose We sought to evaluate the performance of RF-CL and CACS-CL in a symptomatic mixed Asian cohort. Methods The study cohort included symptomatic patients referred for coronary computed tomography angiography (CTA) at a tertiary cardiac centre in Singapore. Patients with known CAD were excluded. Obstructive CAD was defined as ≥ 50% stenosis on coronary CTA. RF-CL was calculated with age, sex, symptom characteristics, and the number of risk factors. CACS-CL was calculated from RF-CL by further incorporating the CACS. Discriminative performance was evaluated with the area under the receiver-operating characteristic curves (AUC). Categorical net reclassification index (NRI) was calculated to assess the reclassification improvement of CACS-CL as compared with RF-CL. Results A total of 1293 patients were analysed (mean age 55.8±11.3 years, 45.6% female). The majority of the patients were of Asian descent (73.9% Chinese, 10.6% Indian, 6.4% Malay). The overall prevalence of obstructive CAD was 26.1% (n=338). The RF-CL achieved an AUC of 0.72 (95% CI, 0.69-0.75). The incorporation of CACS in CACS-CL further improved the AUC to 0.89 (95% CI, 0.87-0.91; p&amp;lt;0.001) (Figure 1). Compared to RF-CL, CACS-CL demonstrated an improved reclassification, resulting in a categorical NRI of 0.28 (95% CI, 0.23-0.33) at a 5% cutoff. Among 955 patients without obstructive CAD, the CACS-CL model reclassified a significant proportion (21.4%, n=204) into the low-risk group, in which further testing is not recommended. (Table 1) Conclusions In a symptomatic mixed Asian cohort, the RF-CL model had good discriminative performance in predicting obstructive CAD. Incorporating CACS in the CACS-CL model improved both discrimination and reclassification substantially. These results indicate that the RF-CL and CACS-CL perform similarly in different ethnicities and support their use in optimising the diagnostic workflow in Asian patients with stable chest pain.

Coronary Computed Tomographic Angiography With Fractional Flow Reserve in Patients With Type 2 Myocardial Infarction

BackgroundType 2 myocardial infarction (T2MI) related to a supply/demand imbalance of coronary blood flow is common and associated with poor prognosis. Coronary artery disease (CAD) may predispose some individuals to T2MI and contribute to its high rate of recurrent cardiovascular events. Little is known about the presence and extent of CAD in this population. ObjectivesThe goal of this study was to evaluate the presence and characteristics of CAD among patients with T2MI. MethodsIn this prospective study, consecutive eligible individuals with Fourth Universal Definition of Myocardial Infarction criteria for T2MI were enrolled. Participants underwent coronary computed tomography angiography (CTA), fractional flow reserve derived with coronary CTA (FFRCT), and plaque volume analyses. ResultsAmong 50 participants, 25 (50%) were female, and the mean age was 68.0 ± 11.4 years. Atherosclerotic risk factors were common. Coronary CTA revealed coronary plaque in 46 participants (92%). A moderate or greater stenosis (≥50%) was identified in 42% of participants, and obstructive disease (≥50% left main stenosis or ≥70% stenosis in any other epicardial coronary artery) was present in 26%. Prevalence of obstructive CAD did not differ according to T2MI cause (P = 0.54). A hemodynamically significant focal stenosis identified by FFRCT was present in 13 participants (26%). Among participants with a stenosis ≥50% (n = 21), FFRCT excluded lesion-specific hemodynamically significant stenosis in 8 cases (38%). ConclusionsAmong individuals with adjudicated T2MI, CAD was prevalent, but the majority of patients had nonobstructive CAD. Mediators of ischemia are likely multifactorial in this population. (Defining the Prevalence and Characteristics of Coronary Artery Disease Among Patients with Type 2 Myocardial Infarction using CT-FFR [DEFINE TYPE 2 MI]; NCT04864119)

Exercise electrocardiography for pre-test assessment of the likelihood of coronary artery disease

ObjectivesTo develop a tool including exercise electrocardiography (ExECG) for patient-specific clinical likelihood estimation of patients with suspected obstructive coronary artery disease (CAD).MethodsAn ExECG-weighted clinical likelihood (ExECG-CL) model was developed in...

Influence of Age on the Diagnostic Value of Coronary Artery Calcium Score for Ruling Out Obstructive Coronary Disease in Symptomatic Patients

Concerns have been raised about the added diagnostic value of coronary artery calcium score (CACS) of 0 for reducing the likelihood of obstructive coronary artery disease (CAD) in younger patients. Our study aimed to assess the influence of age on the value of CAC=0 in symptomatic patients who underwent coronary computed tomography angiography (CCTA). We conducted a 2-center retrospective study assessing symptomatic patients with suspected CAD who underwent CACS and CCTA. Pretest probability was calculated according to the Juarez-Orozco method and obstructive CAD was defined as ≥50% luminal stenosis. The diagnostic likelihood ratios and negative predictive values were used to assess the diagnostic value of a CACS of 0 to rule out obstructive CAD. A total of 2,043 patients (mean age 60 ± 11years, 60% women, 48.5% CACS of 0) were analyzed. The pretest probability of obstructive CAD increased with age, whereas the proportion of patients with a CACS of 0 decreased with age. The added diagnostic value of a CACS of 0 was lower in younger patients (negative likelihood ratios ranging from 0.36 for <50years to 0.10 for ≥70years). However, the prevalence of obstructive CAD in patients with a CACS of 0 was low in all age groups. In a cohort of symptomatic patients who underwent CCTA for suspected CAD, the added diagnostic value of a CACS of 0 decreases significantly at younger ages. However, it is offset by their lower pretest probabilities, yielding high negative predictive values independently of age.

Implications of three different testing strategies in the diagnostic approach to patients with stable chest pain and low pretest probability of obstructive coronary artery disease

IntroductionThe clinical implications of a widespread adoption of guideline recommendations for patients with stable chest pain and low pretest probability (PTP) of obstructive coronary artery disease (CAD) remain unclear. We aimed to assess the results of three different testing strategies in this subgroup of patients: A) defer testing; B) perform coronary artery calcium score (CACS), withholding further testing if CACS ​= ​0 and proceeding to coronary computed tomography angiography (CCTA) if CACS>0; C) perform CCTA in all. MethodsTwo-center cross-sectional study assessing 1328 symptomatic patients undergoing CACS and CCTA for suspected CAD. PTP was calculated based on age, sex and symptom typicality. Obstructive CAD was defined as any luminal stenosis ≥50% on CCTA. ResultsThe prevalence of obstructive CAD was 8.6% (n ​= ​114). In the 786 patients (56.8%) with CACS ​= ​0, 8.5% (n ​= ​67) had some degree of CAD [1.9% (n ​= ​15) obstructive, and 6.6% (n ​= ​52) nonobstructive]. Among those with CACS>0 (n ​= ​542), 18.3% (n ​= ​99) had obstructive CAD. The number of patients needed to scan (NNS) to identify one patient with obstructive CAD was 13 for strategy B vs. A, and 91 for strategy C vs. B. ConclusionsUsing CACS as gatekeeper would decrease CCTA use by more than 50%, at the cost of missing obstructive CAD in one in 100 patients. These findings may help inform decisions on testing, which will ultimately depend on the willingness to accept some diagnostic uncertainty.

Predictive value of a positive stress single-photon emission computed tomography or stress cardiac magnetic resonance for ruling in obstructive coronary artery disease in a real-world setting

Introduction and objectivesRandomized controlled trials comparing stress cardiac magnetic resonance (CMR) and single-photon emission computed tomography (SPECT) suggest similar diagnostic accuracy for detecting obstructive coronary artery disease (CAD). There are few data on whether this remains true in routine clinical practice.The aim of this study was to assess clinical and angiographic characteristics of patients undergoing invasive coronary angiography (ICA) after stress CMR or SPECT, and to compare their positive predictive value with published results from the CE-MARC trial. MethodsIn this retrospective tertiary-center analysis, we included 429 patients undergoing ICA after a positive stress CMR or positive SPECT performed within the previous 12 months. Obstructive CAD was defined as any coronary artery stenosis ≥50% in a vessel compatible with the ischemic territory on stress testing. ResultsOf the total 429 patients, 356 (83%) were referred after a positive SPECT, and 73 (17%) after a positive stress CMR. Patients did not differ according to age, cardiovascular risk factors, previous revascularization or left ventricular dysfunction, but patients with SPECT were more frequently male (p=0.046). The prevalence of obstructive CAD was similar in patients with positive SPECT vs. positive stress CMR (76.1% vs. 80.8%, respectively, p=0.385). The positive predictive values of both techniques were similar to those reported in the CE-MARC trial. ConclusionIn this tertiary center analysis, stress CMR and SPECT showed similar positive predictive values, comparable to those reported in the CE-MARC trial. This finding supports the emerging adoption of CMR in clinical practice for the diagnosis and management of CAD.

Correlation of Duke Treadmill Score with Coronary angiographic Findings in Patients with Stable Ischemic Heart Disease

Aim: To determine the correlation of Duke treadmill score with angiographically determined obstructive coronary artery disease (CAD) Study design: observational cross sectional study, comparative type Place and duration: The study was done at Cardiac Center Bahawalpur from August 2020 to July 2021. Methods: The patients who had stable angina and underwent exercise tolerance testing as well as coronary angiography were included in the study. The data was collected on a predesigned proforma. The difference in the prevalence of obstructive CAD with regards to Duke treadmill score (DTS), gender, diabetes mellitus, hypertension, smoking and family history was determined with Chi square test using SPSS 20; ap value of &lt; 0.05 was taken as significant. Results: Total 71 patients were enrolled for study. Mean ageof the participants was 48.25 ± 8.7 years. It was a male dominant population. A significant difference in the prevalence of obstructive CADwas noted in low, intermediate and high risk groups according to DTS. The prevalence of obstructive coronary artery disease was not significantly different with regards to gender, diabetes mellitus, hypertension, smoking and family history. However obstructive CAD was more prevalent in those who presented with typical angina as compared to those who had atypical symptoms. Conclusion: Obstructive CAD significantly differs in low, intermediate and high risk groups according to DTS. Keywords: Duke treadmill score, coronary artery disease

Coronary artery calcium score as a gatekeeper for further testing in patients with low pretest probability of obstructive coronary artery disease: A cost-effectiveness analysis

Introduction and objectivesCurrent guidelines recommend not routinely testing patients with chest pain and low pretest probability (PTP <15%) of obstructive coronary artery disease (CAD), but envisage the use of risk modifiers, such as coronary artery calcium score (CACS), to refine patient selection for testing. We aimed to assess the cost-effectiveness (CE) of three different testing strategies in this population: (A) defer testing; (B) perform CACS, withholding further testing if CACS=0, and proceeding to coronary CT angiography (CCTA) if CACS>0; (C) CCTA in all. MethodsWe developed a CE model using data from a two-center cross-sectional study of 1385 patients with non-acute chest pain and PTP <15% undergoing CACS followed by CCTA. Key input data included the prevalence of obstructive CAD on CCTA (10.3%), the proportion with CACS=0 (57%), and the negative predictive value of CACS for obstructive CAD on CCTA (98.1%). ResultsNot testing would correctly classify 89.7% of cases and at a cost of €121433 per 1000 patients. Using CACS as a gatekeeper for CCTA would correctly diagnose 98.9% of cases and cost €247116/1000 patients. Employing first-line CCTA would correctly classify all patients, at a cost of €271007/1000 diagnosed patients. The added cost for an additional correct diagnosis was €1366 for CACS±CCTA vs. no testing, and €2172 for CCTA vs. CACS±CCTA. ConclusionsCACS as a gatekeeper for further testing is cost-effective between a threshold of €1366 and €2172 per additional correct diagnosis. CCTA yields the most correct diagnoses and is cost-effective above a threshold of €2172.

Performance of the American Heart Association/American College of Cardiology Guideline-Recommended Pretest Probability Model for the Diagnosis of Obstructive Coronary Artery Disease.

Background Substantial differences exist between different guideline-recommended pretest probability (PTP) models for the detection of obstructive coronary artery disease (CAD). This study was performed to study the performance of the 2021 American Heart Association/American College of Cardiology (AHA/ACC) guideline-recommended PTP (AHA/ACC-PTP) model in assessing the likelihood of obstructive CAD compared with previously proposed models. Methods and Results Symptomatic patients (N=50 561) referred for coronary computed tomography angiography were included. The reference standard was invasive coronary angiography with optional fractional flow reserve measurements. The AHA/ACC-PTP values based on sex and age were calculated and compared with the 2019 European Society of Cardiology guideline PTP values based on sex, age, and symptoms as well as the risk factor-weighted clinical likelihood values based on sex, age, symptoms, and risk factors. The AHA/ACC-PTP maximum values overestimated by a factor of 2.6 the actual prevalence of CAD. Compared with the AHA/ACC-PTP model (area under the receiver-operating curve, 71.5 [95% CI, 70.7-72.2]), inclusion of typicality of symptoms in the European Society of Cardiology guideline PTP improved discrimination of CAD (area under the receiver-operating curve, 75.5 [95% CI, 74.7-76.3]). Inclusion of both symptoms and risk factors in the risk factor-weighted clinical likelihood model further improved discrimination (area under the receiver-operating curve, 77.7 [95% CI, 77.0-78.5]). The proportion of patients classified as very low PTP was lower using the AHA/ACC-PTP (5%) compared with the European Society of Cardiology guideline PTP (19%) and the risk factor-weighted clinical likelihood (49%) models. Conclusions The new AHA/ACC-PTP model overestimates the prevalence of obstructive CAD substantially if type of symptoms and risk factors are not taken into account. Inclusion of both symptoms and risk factors improves model performance and identifies more patients with very low likelihood of CAD in whom further testing can be deferred.

High incidence of newly diagnosed obstructive coronary artery disease regardless of chest pain detected on pre-procedural cardiac computed tomography angiography in patients undergoing atrial fibrillation ablation.

Cardiac computed tomography (CT) is often performed before catheter ablation of atrial fibrillation to map atrial and pulmonary anatomy. Incident coronary artery disease (CAD) may also be diagnosed during cardiac CT angiography (CTA). Our aim was to assess whether coronary CTA might be able to identify a significant proportion of patients with obstructive CAD prior to their catheter ablation procedure event, even in asymptomatic patients. Consecutive patients undergoing pre-ablation coronary CTA for atrial fibrillation between 2013 and 2020 were retrospectively selected. Patients with previously diagnosed CAD were excluded. Obstructive CAD was defined as ≥50% luminal stenosis. We analyzed the relationship between obstructive CAD, any chest pain, and traditional risk factors. Overall, 2321 patients [median age 63.0 (54.4-69.2), 1052/2321 (45.3%) female] underwent coronary CTA and 488/2321 (21.0%) were diagnosed with obstructive CAD. There was no difference regarding the rate of obstructive CAD in patients with any chest pain compared to patients without any chest pain [91/404 (22.5%) vs. 397/1917 (20.7%), P = 0.416, respectively). The following parameters were associated with obstructive CAD: age > 65 years [odds ratio (OR) = 2.51; 95% confidence interval (CI), 2.02-3.13; P < 0.001), male sex (OR = 1.59; 95% CI, 1.28-1.98; P < 0.001), hypertension (OR = 1.40; 95% CI, 1.08-1.81; P = 0.012), diabetes (OR = 1.50; 95% CI, 1.13-1.99; P = 0.006), dyslipidaemia (OR = 1.33; 95% CI, 1.07-1.66; P = 0.011) and history of smoking (OR = 1.34; 95% CI, 1.07-1.68; P = 0.011). The high prevalence of obstructive CAD even in patients without chest pain highlights the importance of additional coronary artery diagnostics in patients undergoing left atrial CTA awaiting catheter ablation for atrial fibrillation. These patients regardless of chest pain thus may require further risk modification to decrease their potential ischemic and thromboembolic risk.

Abstract 10918: Sex Differences in the Association of Triglyceride Glucose Index in Patients With Obstructive Coronary Artery Disease

Background: Insulin resistance is associated with cardiovascular disease due to direct or associated risk factors. We aimed to investigate the association of the Triglyceride glucose (TyG) index, as the surrogate marker of insulin resistance and obstructive coronary artery disease (CAD) between sex, especially for patients without diabetes. Methods: Patients with stable angina pectoris requiring invasive coronary angiography were enrolled, and they were divided into two groups according to the TyG index (ln[triglyceride x fasting plasma glucose]/2). Obstructive CAD was defined according to invasive coronary angiography results. Results: Patients with a higher TyG index (TyG index≧8.60) were associated with higher BMI, the prevalence of hypertension (HTN), diabetes mellitus (DM), and abnormal lipid profile compared with lower TyG index (TyG index &lt; 8.60). In women without diabetes, higher TyG index patients had a greater prevalence of obstructive CAD than the lower TyG index group (19.5% vs. 37.7%, p-value: 0.011). There was no difference in the majority of obstructive CAD in male patients between lower and higher TyG index. In multivariate logistic regression analysis, a higher TyG index remained the independent association of obstructive CAD only in women without diabetes (adjusted odds ratio (OR): 2.568, 95% CI: 1.238-5.327, p= 0.011) but not in the DM group. Conclusion: Higher TyG index, a marker of insulin resistance, was significantly related to a higher risk of obstructive CAD with gender disparity in patients without diabetes. Further larger-scale studies are needed to confirm our findings.

Influence of age on the diagnostic value of coronary artery calcium score for ruling out coronary stenosis in symptomatic patients

Abstract Background The 2021 Guideline for the Evaluation of Chest Pain supports the use of coronary artery calcium (CAC) score as a reasonable first-line test to identify patients with a low likelihood of obstructive coronary artery disease (CAD) who may not require additional testing (class IIa, LOE B). However, a recent study from a large cohort of Northern European patients raised concerns about the added diagnostic value of CAC=0 in younger patients. The aim of this study was to assess the influence of age on the value of CAC=0 in symptomatic patients undergoing coronary computed tomography angiography (CCTA). Methods We conducted a two-center cross-sectional study assessing symptomatic patients with suspected CAD who underwent CAC score and CCTA. Key exclusion criteria were age &amp;lt;30 years, known CAD, suspected acute coronary syndrome, or symptoms other than chest pain or dyspnea. Pretest probability of obstructive CAD was calculated based on age, sex and symptom typicality, according to the guideline-recommended method. Obstructive CAD was defined as any luminal stenosis ≥50% on CCTA. The diagnostic likelihood ratios and negative predictive values (NPV) were used to assess the diagnostic value of a CAC score of 0 to rule out obstructive CAD. Results A total of 2043 patients (mean age 60±11 years, 60% women) of whom 990 (48.5%) had a CAC score of 0 were included in the analysis. Symptom characteristics were: 38% non-anginal chest pain, 30% atypical angina, 19% dyspnea, and 13% typical chest pain. Overall, the prevalence of obstructive CAD was 12.8% (n=262). Pretest probability of obstructive CAD increased progressively with age, from 6.0% in patients young than 50 years to 20.7% in those 70 years or older. Contrariwise, the prevalence of patients with a CAC score = 0 decreased from 77% in patients younger than 50 years, to 26% in those who where 70 years or older. The added diagnostic value of a CAC score = 0 was lower in younger patients, with negative likelihood ratios ranging from 0.36 (64% decrease in the likelihood of CAD) in patients younger than 50 years, to 0.09 and 0.10 (∼90% decrease in the likelihood of CAD) in those aged 60–69 years and 70 years or older, respectively – Figure 1. Despite this, the prevalence of obstructive CAD among patients with a CAC score = 0 was low across all age groups: 2.4% (i.e., NPV = 97.6%) in those younger than 50 years, 3.0% (NPV = 97.0%) among those aged 50–59 years, 1.5% (NPV = 98.5%) in patients between 60 and 69 years, and 2.0% (NPV = 98.0%) among those 70 years or older. Conclusions In a cohort of symptomatic patients undergoing CCTA for suspected CAD, the added diagnostic value of a CAC score of zero decreases significantly at younger ages. However, this “diminishing return” of CAC in younger patients if offset by their lower pretest probabilities, yielding high negative predictive values independently of age. Funding Acknowledgement Type of funding sources: None.

Implications of the North American 2021 Chest Pain guidelines in the diagnostic approach to patients with stable chest pain and low pretest probability of obstructive coronary artery disease

Abstract Background The North American 2021 Chest Pain Guidelines recommend not testing stable patients with low pretest likelihood of obstructive coronary artery disease (CAD), defined as pretest probability &amp;lt;15% using contemporary models (Class I recommendation). In selected cases among this subset of patients, coronary artery calcium (CAC) score is considered a “reasonable first-line test” (Class IIa). Despite some supporting evidence, the clinical implications of a widespread adoption of these recommendations remain unclear. The purpose of this study was to assess the results of three different testing strategies for patients with pretest probability &amp;lt;15%: A) defer testing; B) perform CAC score and withhold further testing if = 0, and proceed to coronary CT angiography (CCTA) if &amp;gt;0; C) perform CCTA in all. Methods We conducted a two-center cross-sectional study assessing symptomatic patients with suspected CAD who underwent CAC score and CCTA. Patients with known CAD, suspected acute coronary syndrome, or symptoms other than chest pain or dyspnea were excluded. Pretest probability of obstructive CAD was calculated based on age, sex and symptom typicality. Obstructive CAD was defined as any luminal stenosis ≥50% on CCTA. Results A total of 2259 patients were screened, of which 1385 (61.3%) had pretest probability &amp;lt;15% and were included in the analysis (mean age 57±11 years, 79% women). Symptom characteristics were: 48% non-anginal chest pain, 26% atypical angina, 21% dyspnea, and 5% typical chest pain. Overall, the prevalence of obstructive CAD was 10.3% (n=142). In the 786 patients (56.6%) with a CAC score of 0, 8.5% (n=67) had some degree of CAD [1.9% (n=15) obstructive, and 6.6% (n=52) nonobstructive]. Among those with CAC &amp;gt;0 (n=599), 21.2% (n=127) had obstructive CAD. The results that would be reached with each of the 3 diagnostic strategies are presented in Figure 1. The number of patients needed to scan with strategy B (CAC as gatekeeper) vs. A (no testing) to identify one patient with obstructive CAD was 11, whereas the number needed to scan with strategy C (CCTA for all) vs. strategy B was 91. Conclusions Not testing patients with suspected CAD and pretest likelihood &amp;lt;15% would lead to missing obstructive CAD in 1 out of 10 patients. Using CAC as a gatekeeper in this subgroup would decrease the use of CCTA by more than 50%, at the cost of missing obstructive CAD in 1 out of 100 patients. These findings may be used to inform decisions on testing, which will ultimately depend on how much diagnostic uncertainty and missed diagnoses patients and their physicians are willing to accept. Funding Acknowledgement Type of funding sources: None.