Noninvasive Stress Testing Research Articles

The impact of stress testing to guide PCI in patients with chronic coronary disease

BackgroundGuidelines and international appropriate use criteria increasingly endorse non-invasive stress testing to evaluate patients with suspected chronic coronary disease (CCD). We sought to review the real-world utilisation of non-invasive stress testing and investigate whether their use prior to PCI associates with outcomes in patients with CCD. MethodsConsecutive patients from a multicentre registry who underwent PCI for CCD between 2006 and 2018 were included. Clinical characteristics and outcomes were stratified according to whether stress testing was performed prior to PCI (stress vs no-stress groups). The primary outcome was 3-year all-cause mortality. ResultsAmong the 8251 patients included, 4970 (60.2 %) underwent pre-PCI stress testing and this proportion increased over time (p-for-trend<0.001). The stress group had a lower prevalence of prior revascularization, myocardial infarction, or heart failure, and a lower incidence of triple vessel disease, in stent re-stenosis, and ACC/AHA class B2/C lesions (all p < 0.001). When comparing post-procedural outcomes, the stress group had lower rates of arrhythmia (1.5 % vs 2.6 %, p = 0.001), new heart failure (0.2 % vs 0.8 %, p = 0.001), renal impairment, and a shorter length of stay (1.6 vs 2.1 days, p < 0.001). Mortality at 3-years was lower in those undergoing PCI following stress testing (5.8 % vs 8.8 %, p < 0.001). After adjusting for key clinical variables, stress guided revascularization was associated with a significantly lower risk of 3-year mortality (adjusted Hazard Ratio 0.77, 95 % CI 0.64–0.92). ConclusionsIn patients with CCD, PCI guided by non-invasive stress testing is increasingly utilized and associated with improved survival. Further studies are necessary to investigate whether this results from differences in patient characteristics, optimized patient selection, or refined choice of target vessel.

2024 Guidelines of the Taiwan Society of Cardiology for the Diagnosis and Treatment of Heart Failure with Preserved Ejection Fraction.

Heart failure with preserved ejection fraction (HFpEF) is a multi-organ systemic syndrome that involves cardiac and extra-cardiac pathophysiological abnormalities. Its growing prevalence causes a major public concern worldwide. HFpEF is usually associated with multiple comorbidities, and non-cardiovascular death is common in patients with HFpEF. In Asia, patients with HFpEF has a younger age, higher prevalence of diabetes and chronic kidney disease than Western countries. A 2-step diagnostic algorithm is recommended in this guideline. In the first step, the diagnosis of HFpEF can be made if patients have symptoms and/or signs of heart failure, left ventricular ejection fraction ≥ 50%, increased natriuretic peptide, and objective evidence of left atrial or left ventricular abnormalities or raised left ventricular filling pressure. If diagnosis is still uncertain, invasive or noninvasive stress test can be performed in the second step. Comorbidities need to be controlled in HFpEF. Weight reduction for obesity and supervised exercise training are recommended for HFpEF. For pharmacological therapy, diuretic is used to relieve congestion and sodium-glucose cotransporter 2 inhibitor, empagliflozin or dapagliflozin, is recommended to improve prognosis of HFpEF. The research on HFpEF is advancing at a rapid pace. It is expected that newer modalities for diagnosis and management of HFpEF could appear in the near future.

Predicting major adverse cardiovascular events after orthotopic liver transplantation using a supervised machine learning model: A cohort study.

Liver transplant (LT) patients have become older and sicker. The rate of post-LT major adverse cardiovascular events (MACE) has increased, and this in turn raises 30-d post-LT mortality. Noninvasive cardiac stress testing loses accuracy when applied to pre-LT cirrhotic patients. To assess the feasibility and accuracy of a machine learning model used to predict post-LT MACE in a regional cohort. This retrospective cohort study involved 575 LT patients from a Southern Brazilian academic center. We developed a predictive model for post-LT MACE (defined as a composite outcome of stroke, new-onset heart failure, severe arrhythmia, and myocardial infarction) using the extreme gradient boosting (XGBoost) machine learning model. We addressed missing data (below 20%) for relevant variables using the k-nearest neighbor imputation method, calculating the mean from the ten nearest neighbors for each case. The modeling dataset included 83 features, encompassing patient and laboratory data, cirrhosis complications, and pre-LT cardiac assessments. Model performance was assessed using the area under the receiver operating characteristic curve (AUROC). We also employed Shapley additive explanations (SHAP) to interpret feature impacts. The dataset was split into training (75%) and testing (25%) sets. Calibration was evaluated using the Brier score. We followed Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis guidelines for reporting. Scikit-learn and SHAP in Python 3 were used for all analyses. The supplementary material includes code for model development and a user-friendly online MACE prediction calculator. Of the 537 included patients, 23 (4.46%) developed in-hospital MACE, with a mean age at transplantation of 52.9 years. The majority, 66.1%, were male. The XGBoost model achieved an impressive AUROC of 0.89 during the training stage. This model exhibited accuracy, precision, recall, and F1-score values of 0.84, 0.85, 0.80, and 0.79, respectively. Calibration, as assessed by the Brier score, indicated excellent model calibration with a score of 0.07. Furthermore, SHAP values highlighted the significance of certain variables in predicting postoperative MACE, with negative noninvasive cardiac stress testing, use of nonselective beta-blockers, direct bilirubin levels, blood type O, and dynamic alterations on myocardial perfusion scintigraphy being the most influential factors at the cohort-wide level. These results highlight the predictive capability of our XGBoost model in assessing the risk of post-LT MACE, making it a valuable tool for clinical practice. Our study successfully assessed the feasibility and accuracy of the XGBoost machine learning model in predicting post-LT MACE, using both cardiovascular and hepatic variables. The model demonstrated impressive performance, aligning with literature findings, and exhibited excellent calibration. Notably, our cautious approach to prevent overfitting and data leakage suggests the stability of results when applied to prospective data, reinforcing the model's value as a reliable tool for predicting post-LT MACE in clinical practice.

Safety and Outcomes of Same-Day Discharge Versus Overnight Observation After Transradial Percutaneous Coronary Intervention: A Retrospective Cohort Study in a Tertiary Hospital in Philippines

INTRODUCTION: Since earlier days of percutaneous coronary intervention (PCI), there has been improvement in several aspects of PCI including use of transradial approach and third-generation drug-eluting stents. Despite data showing its safety, same-day discharge (SDD) PCI has not been widely practiced in our institution and country. At present, there are no published studies from the Philippines showing the safety and outcome of SDD PCI. OBJECTIVES: The primary objective of this study is to determine and compare the safety and outcomes of SDD versus overnight observation after PCI in The Medical City from 2018 to 2021. METHODS: This was a retrospective cohort study. The primary endpoint was to describe and compare the clinical profile of patients who underwent same-day versus overnight observation after PCI such as age, sex, comorbidities, indication for coronary angiogram, procedure time, total dye used, stent, and drug-eluting stent used. Incidence of major adverse cardiovascular event, mortality, readmission, and access site complications were also determined at 48 hours and 30 days after PCI. RESULTS: Ninety-three patients were included in the analysis. Reasons for undergoing PCI were a positive noninvasive stress test (45%), stable angina (40%), coronary artery disease (26%), and heart failure (20%). More single-vessel (60%) than multivessel (40%) PCIs were performed. The most frequently affected coronary artery was the LAD (82%), followed by right coronary artery (32%) and left circumflex artery (30%). Compared with patients who stayed longer after PCI, the SDD group had lower mean (±SD) body mass index (25.10 ± 3.12 vs 28.55 ± 4.95 kg/m2), less due to a positive noninvasive test (26% vs 51%), more who underwent a single-vessel PCI (78% vs 54%), lower median amount of injected dye (130 vs 188 mL), shorter median procedural time (74 vs 101.5 minutes), and greater use of sirolimus-eluting stent (22% vs 3%). No adverse outcome of interest was noted in any patient up to 30 days after hospital discharge. CONCLUSION: No adverse outcome was noted with SDD PCI. Larger, prospective, randomized comparative studies are needed to ascertain its safety before recommending SDD PCI routinely. KEYWORDS: left anterior descending artery, left circumflex artery, percutaneous coronary intervention, right coronary artery, same-day discharge

Abstract 16082: Racial Differences Among Patients Undergoing Nuclear Myocardial Perfusion Imaging

Introduction: Noninvasive cardiac stress testing is valuable for early diagnosis and optimizing management of patients with coronary artery disease (CAD). Historically, Black patients have experienced both underdiagnosis and undertreatment of CAD. We evaluated racial disparities in patients undergoing nuclear myocardial perfusion imaging (MPI). Different modalities (MPI (SPECT, PET) vs. stress echocardiography) have variations in accuracy, cost and radiation exposure, which may reflect provider biases. Methods: Patient-reported demographics, clinician-reported cardiac risk factors and MPI study characteristics from a large Connecticut health system (2016 - 2022) were compared for Black and White patients in both general and matched cohorts (1:1 matched for demographics and risk factors). Results: The study included 123,069 cardiac stress tests from 10.5% Black and 76.2% White patients (largely similar to overall Connecticut population: 12.7% Black, 78.8% White). Black patients were younger (56.7±13.3 vs. 62.1±13.4 years, p&lt; 0.001), more likely female (58.7 vs. 44.7%, p&lt;0.001) and had more risk factors (Table 1). Black patients were more likely to undergo MPI (66.6 vs. 50.5%, p&lt;0.001), inpatient or observation status testing (17.0 vs. 8.4%, p&lt; 0.001), with pharmacological rather than exercise stress (53.9 vs. 37.0%, p&lt;0.001) than White patients. On analysis of the 1:1 matched cohort, Black patients younger than 65 years were more likely to undergo MPI than White patients (62.1 vs. 57.4%, p&lt;0.001), while the reverse is seen for patients over 65 years old (37.5 vs. 42.5%, p&lt;0.001). Conclusion: Significant demographic and stress testing pattern differences were found between Black and White patients. These findings may reflect racial disparities in cardiovascular care, including access and clinical referral patterns. Further studies are needed to determine if these differences in stress testing strategies impact downstream clinical outcomes.

Phenotyping heart failure by echocardiography: imaging of ventricular function and haemodynamics at rest and exercise.

Traditionally, congestive heart failure (HF) was phenotyped by echocardiography or other imaging techniques according to left ventricular (LV) ejection fraction (LVEF). The more recent echocardiographic modality speckle tracking strain is complementary to LVEF, as it is more sensitive to diagnose mild systolic dysfunction. Furthermore, when LV systolic dysfunction is associated with a small, hypertrophic ventricle, EF is often normal or supernormal, whereas LV global longitudinal strain can reveal reduced contractility. In addition, segmental strain patterns may be used to identify specific cardiomyopathies, which in some cases can be treated with patient-specific medicine. In HF with preserved EF (HFpEF), a diagnostic hallmark is elevated LV filling pressure, which can be diagnosed with good accuracy by applying a set of echocardiographic parameters. Patients with HFpEF often have normal filling pressure at rest, and a non-invasive or invasive diastolic stress test may be used to identify abnormal elevation of filling pressure during exercise. The novel parameter LV work index, which incorporates afterload, is a promising tool for quantification of LV contractile function and efficiency. Another novel modality is shear wave imaging for diagnosing stiff ventricles, but clinical utility remains to be determined. In conclusion, echocardiographic imaging of cardiac function should include LV strain as a supplementary method to LVEF. Echocardiographic parameters can identify elevated LV filling pressure with good accuracy and may be applied in the diagnostic workup of patients suspected of HFpEF.

Impact of physician performed point of care ultrasound (POCUS) during first outpatient cardiology consultation on patient management and downstream testing.

Goal directed point of care ultrasound (POCUS) is a bedside tool to assist with clinical diagnosis. We examined the impact of POCUS performed by consulting cardiologist (CC) during initial cardiology consult on clinical management and downstream testing. Sixty-nine study patients (pts) seen in a general cardiology outpatient clinic of a tertiary center by an expert imaging CC were compared to a control group of 65 pts seen by three different CCs without POCUS during the same time-period, in whom the first standard echo (SE) was performed after the initial visit. Baseline characteristics were similar between the two groups for age, cardiac risk factors, and referral diagnoses. Echo findings on POCUS and by SE (mean delay of 17.2days after visit) in the control group were comparable for RV size and function and for valvular heart disease. More patients with lower LVEF, higher LV filling pressures, new regional wall motion abnormalities, and increased aortic root size were present among POCUS group resulting in greater yield of echo abnormalities. There were more cardiovascular medication changes at the first visit (15.3% vs. 5.7%, p<.01), less referral for noninvasive stress testing (10% vs. 29%, p<.01), more advanced cardiac testing and subspecialty referrals (29% vs. 18% pts, p=.06), in the study compared to the control group after cardiology visit. POCUS at time of consultation detects more abnormal echo findings, results in more medication adjustments, less referral for noninvasive stress testing, earlier referral for advanced cardiac diagnostic imaging, and subspecialty cardiac referrals.

Improving diagnostic assessments in the ever-changing landscape of atherosclerosis.

As our understanding of atherosclerotic vascular injury continues to evolve, so should our diagnostic approaches. Emerging data have recently challenged our basic understanding in linking ischemia to its adverse outcomes as well as the need for invasive testing for both diagnosis and treatment. The advent of coronary computed tomography in providing improved visualization of coronary arteries has led to the identification of both subclinical atherosclerosis and high-risk coronary lesions. Recognition of asymptomatic coronary artery disease (CAD) with objective localization of subclinical coronary atherosclerosis improves atherosclerotic cardiovascular risk assessment and allows healthcare providers to take effective primary prevention measures. Therefore, reshaping the diagnostic landscape in proposing new testing modalities would be highly dependent on local resource availability and the reading expertise of each clinical practice and medical institution. The main objective of this Review is to propose a potentially new diagnostic approach of simply using noninvasive stress testing or coronary angiography in the routine assessment of CAD.

Qualitative and Quantitative Stress Perfusion Cardiac Magnetic Resonance in Clinical Practice: A Comprehensive Review.

Stress cardiovascular magnetic resonance (CMR) imaging is a well-validated non-invasive stress test to diagnose significant coronary artery disease (CAD), with higher diagnostic accuracy than other common functional imaging modalities. One-stop assessment of myocardial ischemia, cardiac function, and myocardial viability qualitatively and quantitatively has been proven to be a cost-effective method in clinical practice for CAD evaluation. Beyond diagnosis, stress CMR also provides prognostic information and guides coronary revascularisation. In addition to CAD, there is a large body of literature demonstrating CMR's diagnostic performance and prognostic value in other common cardiovascular diseases (CVDs), especially coronary microvascular dysfunction (CMD). This review focuses on the clinical applications of stress CMR, including stress CMR scanning methods, practical interpretation of stress CMR images, and clinical utility of stress CMR in a setting of CVDs with possible myocardial ischemia.

Risk Stratification in Patients with Coronary Artery Disease: Timeliness of Invasive Interventions

Coronary artery disease (CAD) remains a top cause of morbidity and mortality nowadays. Current guidelines are used to deϐine timely diagnostic and management strategies for a patient with new angina symptom. According to the guidelines, the main purpose is assessment of the pretest probability of obstructive CAD. Exercise electrocardiography is the most accessible methodwith 85-90% speciϐicity and 45-50% sensitivity. Cardiopulmonary exercise testing (CPET) with concomitant monitoring of electrocardiogram, heart rate and blood pressure, expired gas analysis has become widespread among different exercise tests. CPET is an important clinical tool to estimate exercise capacity. In most cases it allowsto determine the causes of limited physical activity, evaluate both the blood supply (pulmonary, cardiovascular, haematopoietic systems) and tissue oxygen metabolism (skeletal muscle system) in response to physical exercise.The indications for invasive coronary angiography include: high clinical risk of CAD, symptoms which are refractory to medical therapy, low tolerance to exercise or if revascularization is considered for improvement of prognosis.&#x0D; The aim. To highlight the need for a combination of non-invasive stresstesting (CPET, stress echocardiography) and invasive testing (such as coronary angiography) to develop proper tactics of treating patients with established CAD.&#x0D; Conclusion. Described clinical case demonstrates preferences of combined different functional non-invasive tests (CPET, stress echocardiography) in a patient with confirmed CAD, who received prognosis modifying therapy and had high exercise tolerance due to regular cardio training. This gave the reason for postponing the repeated ICA to determine the dynamics of the progression of coronary atherosclerosis. However, when an anginal attack occurred and repeated urgent ICA was performed, it became necessary to perform coronary artery bypass grafting and, later, due to the continuation of anginal attacks and the presence of areas of ischemia, stenting of the trunk of the left coronary artery.

Abstract 11224: Anatomical Characteristics of Myocardial Bridging and Its Impact on Myocardial Ischemia in Patients With Nonobstructive Coronary Artery Disease

Introduction. Epicardial coronary arteries running through the myocardium (myocardial bridges: MBs) are compressed during myocardial contraction and may be involved in myocardial ischemia. However, the anatomical characteristics of MBs and their impact on myocardial ischemia have not been well characterized. Methods. We included 626 patients who underwent coronary artery computed tomography to evaluate ischemic signs and/or symptoms (mean age 66±13 years, 32% males). Curved multiplanar reformation images were used to assess MBs' presence, length, and thickness. In patients with positive noninvasive stress testing (NST), we compared the frequency and anatomical characteristics of MBs between patients with obstructive coronary arteries (OCA defined as &gt;50% stenosis in main branches) and those with nonobstructive coronary arteries (INOCA). Results. MBs were found in 176 patients (28%), of which 45% were superficial (≤2 mm), 54% were deep (2-5 mm), and 1% were very deep (&gt;5 mm) MBs (mean MB thickness 2.2±0.9 mm). The mean MB length was 18.2±5.7 mm with 14% long MBs (≥25 mm). Ninety-four out of 202 patients undergoing NST presented positive results, 62 of whom had OCA and 32 had INOCA. MBs were more frequently observed in patients with INOCA than in those with OCA (63% vs. 39%, P=0.03) (Figure A). Interestingly, INOCA patients tended to have longer MBs than those with OCA (20.7±6.0 mm vs. 17.6±5.4 mm, P=0.08), whereas MB thickness was not different between the two groups (2.3±0.7 vs. 2.0±0.6, P=0.19) (Figure B). Conclusion. Longer MBs may significantly impact myocardial perfusion, potentially producing positive results on stress tests in patients with INOCA.

Abstract 14139: Differential Benefit of Non-Invasive Cardiac Stress Testing by HEART Score Risk Stratification

Introduction: AHA guidelines recommend non-invasive cardiac testing (NIT) within 72 hours after an emergency department (ED) evaluation for suspected acute coronary syndrome (ACS), after acute myocardial infarction (AMI) has been excluded. However, the effectiveness of this strategy to reduce the risk of future AMI or death, in low-risk patients is contested. Hypothesis: We hypothesized that in patients with low risk based on history, electrocardiogram, age, risk factors and troponin (HEART) based scoring, early NIT may not be beneficial compared to higher risk. Methods: We compared the effectiveness of early NIT vs. no early testing, in a retrospective cohort of adult (age ≥18) members of the Kaiser Permanente Southern California health system from 05/2016-12/2020. We included all adults presenting at EDs with suspected ACS and who had data to compute HEART score. We stratified the cohort into low risk (score 0-3); intermediate risk (score 4-6) and high-risk (score ≥7) based on HEART score. Within each group, confounder adjusted instrumental variables models were used to evaluate the marginal effect of early NIT, and the number needed to treat (NNT) was calculated as the inverse of the absolute composite risk reduction in death/AMI within 30 days of ED discharge. Results: The cohort included 174,936 patients [61% Low risk (mean age 53; female 58%; early NIT 5%), 36% intermediate risk (mean age 71; female 72%; early NIT 18%), and 3% high risk (mean age 74, female 45%; early NIT 23%)]. The risk reduction in 30-day death/AMI due to early NIT increased progressively through the intermediate-risk (NNT = 59) and high-risk groups (NNT = 24) (Table 1). Risk reduction in the low-risk group was not statistically significant. Conclusions: HEART score based high risk patients may benefit the most from early NIT. However, the majority of the suspected ACS cohort was classified as low risk and the benefit of early NIT on 30-day death/AMI was uncertain in this low-risk group.

Implementation of High-Sensitivity Cardiac Troponin Assays in the United States

BackgroundFew data exist regarding the implementation of high-sensitivity cardiac troponin (hs-cTn) assays in the United States since their approval. ObjectivesThis study sought to explore trends in hs-cTn assay implementation over time and assess the association of their use with in-hospital cardiac testing and outcomes. MethodsThe study examined trends in implementation of hs-cTn assays among participating hospitals in the National Cardiovascular Data Registry Chest Pain-MI [Myocardial Infarction] Registry from January 1, 2019 through September 30, 2021. Associations among hs-cTn use, use of in-hospital diagnostic imaging, and patient outcomes were assessed using generalized estimating equation models with logistic or gamma distributions. ResultsAmong 550 participating hospitals (N = 251,000), implementation of hs-cTn assays increased from 3.3% in the first quarter of 2019 to 32.6% in the third quarter of 2021 (Ptrend < 0.001). Use of hs-cTn was associated with more echocardiography among persons with non–ST-segment elevation acute coronary syndrome (NSTE-ACS; 82.4% vs 75.0%; adjusted odds ratio: 1.43; 95% CI: 1.19-1.73) but not among low-risk chest pain individuals. Use of hs-cTn was associated with less invasive coronary angiography among low-risk patients (3.7% vs 4.5%; adjusted odds ratio: 0.73; 95% CI: 0.58-0.92) but similar use for patients with NSTE-ACS. There was no association between hs-cTn use and noninvasive stress testing or coronary computed tomography angiography testing. Among individuals with NSTE-ACS, hs-cTn use was not associated with revascularization or in-hospital mortality. Use of hs-cTn was associated with a shorter length of stay (median 47.6 hours vs 48.0 hours; ratio: 0.94; 95% CI: 0.90-0.98). ConclusionsImplementation of hs-cTn among U.S. hospitals is increasing, but most U.S. hospitals continue to use less sensitive assays. The use of hs-cTn was associated with modestly shorter length of stay, greater use of echocardiography for NSTE-ACS, and less use of invasive angiography among low-risk patients.

Clustering of patients with inconclusive non-invasive stress testing referred for vasodilator stress cardiovascular magnetic resonance

BackgroundInconclusive non-invasive stress testing is associated with impaired outcome. This population is very heterogeneous, and its characteristics are not well depicted by conventional methods. AimsTo identify patient subgroups by phenotypic unsupervised clustering, integrating clinical and cardiovascular magnetic resonance data to unveil pathophysiological differences between subgroups of patients with inconclusive stress tests. MethodsBetween 2008 and 2020, consecutive patients with a first inconclusive non-invasive stress test referred for stress cardiovascular magnetic resonance were followed for the occurrence of major adverse cardiovascular events (defined as cardiovascular death or myocardial infarction). A cluster analysis was performed on clinical and cardiovascular magnetic resonance variables. ResultsOf 1402 patients (67% male; mean age 70±11years) who completed the follow-up (median 6.5years, interquartile range 5.6–7.5years), 197 experienced major adverse cardiovascular events (14.1%). Three distinct phenogroups were identified based upon unsupervised hierarchical clustering of principal components: phenogroup 1=history of percutaneous coronary intervention with viable myocardial infarction and preserved left ventricular ejection fraction; phenogroup 2=atrial fibrillation with preserved left ventricular ejection fraction; and phenogroup 3=coronary artery bypass graft with non-viable myocardial scar and reduced left ventricular ejection fraction. Using survival analysis, the occurrence of major adverse cardiovascular events (P=0.007), cardiovascular mortality (P=0.002) and all-cause mortality (P<0.001) differed among the three phenogroups. Phenogroup 3 presented the worse prognosis. In each phenogroup, ischaemia was associated with major adverse cardiovascular events (phenogroup 1: hazard ratio 2.79, 95% confidence interval 1.61–4.84; phenogroup 2: hazard ratio 2.59, 95% confidence interval 1.69–3.97; phenogroup 3: hazard ratio 3.16, 95% confidence interval 1.82–5.49; all P<0.001). ConclusionsCluster analysis of clinical and cardiovascular magnetic resonance variables identified three phenogroups of patients with inconclusive stress testing, with distinct prognostic profiles.

The association of new atherosclerosis markers with coronary collaterals in chronic total occlusion patients

Objectives: In the present study, we investigated the relationship between mentioned markers and chronic total occlusion collateral development. Patients and methods: A total of 243 patients (210 males, 33 females; mean age: 63.3±11.5; range, 51 to 76 years) who underwent coronary angiography due to typical chest pain or myocardial ischemia detected in noninvasive stress tests and diagnosed with ≥1 major coronary artery occlusion between January and September 2020 were included in the cross-sectional observational study. The angiographic collateral index was determined according to the Cohen-Rentrop classification. The patients were divided into two groups according to the sufficiency of collateral development: the well-developed collaterals group (n=155) and the poor-developed collaterals group (n=88). Results: Statistically significant parameters in univariate logistic regression analysis were evaluated with multivariate (stepwise) logistic regression analysis; as a result, presence of chronic total occlusion in left anterior descending artery (odds ratio [OR]=2.447; 95% confidence interval [CI], 1.160-5.162; p=0.019), total number of occlusions (OR=3.503; 95% CI, 1.445-8.494; p=0.006), left ventricular ejection fraction (OR=1.056; 95% CI, 1.022-1.091; p=0.001), and the atherogenic index of plasma (OR=0.017; 95% CI, 1.022-1.091; p&lt;0.001) were independently associated with well-developed collaterals. Although the triglyceride-glucose index had statistical significance in the univariate analysis, it was not detected as an independent variable in the multivariate analysis. The monocyte-lymphocyte ratio was not significant in the univariate analysis. Conclusion: Of the new atherosclerosis markers, only the atherogenic index of plasma had an independent association with poor collateral development.

CAD in kidney transplant recipients: a real-world assessment pre-ISCHEMIA-CKD

Abstract Background The ISCHEMIA-CKD trial has shown that an initial invasive strategy, as compared to conservative treatment, did not reduce the risk of death and non-fatal myocardial infarction, nor did it improve quality-of-life in patients with advanced chronic kidney disease (CKD) and coronary artery disease (CAD) with moderate-to-severe ischemia. Similar findings were reported in patients with CKD enlisted for kidney transplantation (KT). We aimed to evaluate screening and treatment CAD strategies in patients who ultimately underwent KT at our center. Methods This is a single-center study of consecutive patients who received a KT from 2015 to 2020. Obstructive CAD was defined whenever one of the following criteria was met: lesion with a stenosis &amp;gt;70% (or &amp;gt;50%, if left main disease) or CAD requiring revascularization, as per the Heart Team discussion. CAD evaluation refers to non-invasive or invasive coronary angiography and/or stress testing, irrespective of clinical scenario. Results A total of 324 patients underwent KT [mean age 55±12 years; 65.1% male; CKD most often due to hypertensive or diabetic nephropathy and polycystic kidney disease – 41.8%; median time from renal replacement therapy (RRT) to KT – 60 (40–88) months]. A flow-chart summarizing CAD diagnosis over time is depicted in Figure 1. Overall, 119 (36.7%) patients had CAD evaluation prior to KT, of whom 21 underwent myocardial revascularization – 8, 12 and 1 patients with acute coronary syndrome (ACS), chronic coronary syndrome (CCS) and silent ischaemia, respectively. At a median time of 46 (25–66) months after KT, 36 (11.1%) more patients had CAD evaluation, of whom 8 underwent percutaneous myocardial revascularization – 6 and 2 for ACS and CCS, respectively. Those with obstructive CAD were older (64 vs 54 years-old; p&amp;lt;0.001), with a higher burden of cardiovascular (CV) risk factors (p&amp;lt;0.001) and more likely to have had a CV death (9.5 vs. 1.0%; p=0.025) or CV hospitalization (38.1 vs. 13.4%; p=0.007). CAD status (revascularized vs. non-revascularized) was not associated with improved major outcomes at follow-up. We found no strong predictors of CAD requiring revascularization post-KT, including time from RRT to KT. There were no patients with refractory angina, left main disease or reduced left ventricular ejection fraction (&amp;lt;40%) in need of myocardial revascularization over follow-up. Conclusions Obstructive CAD was uncommon in our cohort of patients who received a KT, most of whom with asymptomatic or mildly (monthly angina) symptomatic CCS or non-fatal ACS. These findings, together with the most recent evidence, may argue against routine CAD screening in all patients being enlisted for KT. Notwithstanding, randomized evidence is eagerly awaited to further guide treatment decisions in the post-ISCHEMIA-CKD era. Funding Acknowledgement Type of funding sources: None.

Ischemia With Nonobstructive Coronary Arteries: Insights From the ISCHEMIA Trial

BackgroundIschemia with nonobstructive coronary arteries (INOCA) is common clinically, particularly among women, but its prevalence among patients with at least moderate ischemia and the relationship between ischemia severity and non-obstructive atherosclerosis severity are unknown. ObjectivesThe authors investigated predictors of INOCA in enrolled, nonrandomized participants in ISCHEMIA (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches), sex differences, and the relationship between ischemia and atherosclerosis in patients with INOCA. MethodsCore laboratories independently reviewed screening noninvasive stress test results (nuclear imaging, echocardiography, magnetic resonance imaging or nonimaging exercise tolerance testing), and coronary computed tomography angiography (CCTA), blinded to results of the screening test. INOCA was defined as all stenoses <50% on CCTA in a patient with moderate or severe ischemia on stress testing. INOCA patients, who were excluded from randomization, were compared with randomized participants with ≥50% stenosis in ≥1 vessel and moderate or severe ischemia. ResultsAmong 3,612 participants with core laboratory-confirmed moderate or severe ischemia and interpretable CCTA, 476 (13%) had INOCA. Patients with INOCA were younger, were predominantly female, and had fewer atherosclerosis risk factors. For each stress testing modality, the extent of ischemia tended to be less among patients with INOCA, particularly with nuclear imaging. There was no significant relationship between severity of ischemia and extent or severity of nonobstructive atherosclerosis on CCTA. On multivariable analysis, female sex was independently associated with INOCA (odds ratio: 4.2 [95% CI: 3.4-5.2]). ConclusionsAmong participants enrolled in ISCHEMIA with core laboratory-confirmed moderate or severe ischemia, the prevalence of INOCA was 13%. Severity of ischemia was not associated with severity of nonobstructive atherosclerosis. (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches [ISCHEMIA]; NCT01471522)

B-15 | Percutaneous Coronary Intervention Neutralizes Impact of High-Risk Findings on Non-Invasive Cardiac Stress Testing

There is ongoing controversy regarding the role of percutaneous coronary intervention (PCI) versus medical therapy in patients with stable coronary artery disease and findings of mild, moderate, and severe ischemia.

Clinical Relevance of Ischemia with Nonobstructive Coronary Arteries According to Coronary Microvascular Dysfunction.

BackgroundIn the absence of obstructive coronary stenoses, abnormality of noninvasive stress tests (NIT) in patients with chronic coronary syndromes may indicate myocardial ischemia of nonobstructive coronary arteries (INOCA). The differential prognosis of INOCA according to the presence of coronary microvascular dysfunction (CMD) and incremental prognostic value of CMD with intracoronary physiologic assessment on top of NIT information remains unknown.Methods and ResultsFrom the international multicenter registry of intracoronary physiologic assessment (ILIAS [Inclusive Invasive Physiological Assessment in Angina Syndromes] registry, N=2322), stable patients with NIT and nonobstructive coronary stenoses with fractional flow reserve >0.80 were selected. INOCA was diagnosed when patients showed positive NIT results. CMD was defined as coronary flow reserve ≤2.5. According to the presence of INOCA and CMD, patients were classified into 4 groups: group 1 (no INOCA nor CMD, n=116); group 2 (only CMD, n=90); group 3 (only INOCA, n=41); and group 4 (both INOCA and CMD, n=40). The primary outcome was major adverse cardiovascular events, a composite of all‐cause death, target vessel myocardial infarction, or clinically driven target vessel revascularization at 5 years. Among 287 patients with nonobstructive coronary stenoses (fractional flow reserve=0.91±0.06), 81 patients (38.2%) were diagnosed with INOCA based on positive NIT. By intracoronary physiologic assessment, 130 patients (45.3%) had CMD. Regardless of the presence of INOCA, patients with CMD showed a significantly lower coronary flow reserve and higher hyperemic microvascular resistance compared with patients without CMD (P<0.001 for all). The cumulative incidence of major adverse cardiovascular events at 5 years were 7.4%, 21.3%, 7.7%, and 34.4% in groups 1 to 4. By documenting CMD (groups 2 and 4), intracoronary physiologic assessment identified patients at a significantly higher risk of major adverse cardiovascular events at 5 years compared with group 1 (group 2: adjusted hazard ratio [HRadjusted], 2.88; 95% CI, 1.52–7.19; P=0.024; group 4: HRadjusted, 4.00; 95% CI, 1.41–11.35; P=0.009).ConclusionsIn stable patients with nonobstructive coronary stenoses, a diagnosis of INOCA based only on abnormal NIT did not identify patients with higher risk of long‐term cardiovascular events. Incorporating intracoronary physiologic assessment to NIT information in patients with nonobstructive disease allowed identification of patient subgroups with up to 4‐fold difference in long‐term cardiovascular events.RegistrationURL: https://www.clinicaltrials.gov; Unique identifier: NCT04485234.

Appropriateness of Percutaneous Coronary Intervention Performed by Japanese Expert Operators in Patients With Chronic Total Occlusion.

The appropriateness of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) lesions has rarely been investigated.Methods and Results: The Japanese CTO-PCI Expert Registry enrolled consecutive patients undergoing CTO-PCI carried out by highly experienced Japanese CTO specialists who performed more than 50 CTO-PCIs per year and 300 CTO-PCIs in total. This study included patients undergoing CTO-PCI between January 2014 and December 2019. The appropriateness, trends, and differences among the procedures performed by the operators using the 2017 appropriate use criteria were analyzed. Furthermore, we performed a logistic regression analysis to assess whether the appropriateness was associated with in-hospital major adverse cardiovascular and cerebrovascular events (MACCE). Of the 5,062 patients who underwent CTO-PCI, 4,309 (85.1%) patients who did not undergo the non-invasive stress test were classified as having no myocardial ischemia. Of the total cases, 3,150 (62.2%) were rated as "may be appropriate," and 642 (12.7%) as "rarely appropriate" CTO-PCI cases. The sensitivity analyses showed that the number (%) of "may be appropriate" ranged from 4,125 (57.8%) to 4,744 (66.4%) and the number of "rarely appropriate" ranged from 843 (11.8%) to 970 (13.6%) among best and worst scenarios. In a large Japanese CTO-PCI registry, approximately 13% of CTO-PCI procedures were classified as "rarely appropriate". Substantial efforts would be required to decrease the number of "rarely appropriate" CTO-PCI procedures.