2021 AHA/ACC/ASE/CHEST/SAEM/SCCT/SCMR Guideline for the Evaluation and Diagnosis of Chest Pain: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

Accuracy of subtraction fractional flow reserve with computed tomography in identifying early revascularization in patients with coronary artery disease

OBJECTIVES

The diagnostic performance of fractional flow reserve with computed tomography (FFR-CT) is affected by the presence of calcified plaque. Subtraction can remove the influence of calcification in coronary computed tomography angiography (CCTA) to increase confidence in the diagnosis of coronary artery stenosis. Our purpose is to investigate the accuracy of post-subtraction FFR-CT in predicting early revascularization.

DESIGN

Based on CCTA data of 237 vessels from 79 patients with coronary artery disease, subtraction CCTA images were obtained at a local post-processing workstation, and the conventional and post-subtraction FFR-CT measurements and the difference in proximal and distal FFR-CT values of the narrowest segment of the vessel (ΔFFR-CT) were analyzed for their accuracy in predicting early coronary artery hemodynamic reconstruction.

RESULTS

With FFR-CT ≤ 0.8 as the criterion, the accuracy of conventional and post-subtraction FFR-CT measurements in predicting early revascularization was 73.4% and 77.2% at the patient level, and 64.6% and 72.2% at the vessel level, respectively. The specificity of post-subtraction FFR-CT measurements was significantly higher than that of conventional FFR-CT at both the patient and vessel levels (P of 0.013 and 0.015, respectively). At the vessel level, the area under the curve of receiver operating characteristic was 0.712 and 0.797 for conventional and post-subtraction ΔFFR-CT, respectively, showing a difference (P = 0.047), with optimal cutoff values of 0.07 and 0.11, respectively.

CONCLUSION

The post-subtraction FFR-CT measurements enhance the specificity in predicting early revascularization. The post-subtraction ΔFFR-CT value of the stenosis segment > 0.11 may be an important indicator for early revascularization.

2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The "2024 AHA/ACC/ACS/ASNC/HRS/SCA/SCCT/SCMR/SVM Guideline for Perioperative Cardiovascular Management for Noncardiac Surgery" provides recommendations to guide clinicians in the perioperative cardiovascular evaluation and management of adult patients undergoing noncardiac surgery.

METHODS

A comprehensive literature search was conducted from August 2022 to March 2023 to identify clinical studies, reviews, and other evidence conducted on human subjects that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

Recommendations from the "2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery" have been updated with new evidence consolidated to guide clinicians; clinicians should be advised this guideline supersedes the previously published 2014 guideline. In addition, evidence-based management strategies, including pharmacological therapies, perioperative monitoring, and devices, for cardiovascular disease and associated medical conditions, have been developed.

Advancing acute MI care in densely populated low- and middle-income countries (LMICs): innovative stand-alone chest pain units for expedited triage and timely management

Background

The incidence of myocardial infarction (MI) and its adverse effects on health and mortality remain high in densely populated low- and middle-income countries (LMICs). To address the issue of densely populated areas and timely access to primary PCI, chest pain units (CPUs) were deployed at strategic locations in Karachi, with a populace of over 23 million people. This study describes the results of this initiative in expediting MI care.

Methods

Between 2017 and 2023, 18 CPUs, each with a cardiologist, technician, ECG machine, crash cart and an ambulance were placed in high density areas.

Findings

A total of 915,564 patients were seen at 18 CPUs over the study period. 692,444 (75.6%) were categorized as non-cardiac and subsequently discharged. 223,120 (24.6%) patients were directed for additional care. Of these, 9% had ST elevation myocardial infarction (STEMI) (19, 580), 29% NSTE ACS/Unstable angina, and 31% with various other cardiac conditions. Additionally, 31% were referred for medical outpatient evaluation. CPU inception led to a significant annual growth (16-20%) in primary PCI procedures at NICVD, totaling 20,000 by 2022-2023. The median first medical contact to device time was 100 min (IQR 80-135), while total ischemic was 232 min (IQR: 172-315; 5th -95th %le: 50-920). The overall in-hospital mortality rate for patients undergoing primary PCI was 5.58%, with a range between 5.1% and 6.9% through the study period.

Interpretation

Novel standalone chest pain units, operational from 2017 in Karachi, Pakistan, have expedited triage and enhanced the timely management of AMI. This initiative's transformative impact presents a model that resonates beyond borders, serving as a role model for global healthcare systems.

Funding

The CPU and primary PCI program is fully funded by the government of Sindh. No specific funding was allocated for this study.

Canadian Association of Radiologists Cardiovascular Imaging Referral Guideline

The Canadian Association of Radiologists (CAR) Cardiovascular Expert Panel is made up of physicians from the disciplines of radiology, cardiology, and emergency medicine, a patient advisor, and an epidemiologist/guideline methodologist. After developing a list of 30 clinical/diagnostic scenarios, a rapid scoping review was undertaken to identify systematically produced referral guidelines that provide recommendations for one or more of these clinical/diagnostic scenarios. Recommendations from 48 guidelines and contextualization criteria in the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) for guidelines framework were used to develop 125 recommendation statements across the 30 scenarios (27 unique scenarios as 2 scenarios point to the CAR Thoracic Diagnostic Imaging Referral Guideline and the acute pericarditis subscenario is included under 2 main scenarios). This guideline presents the methods of development and the referral recommendations for acute chest pain syndromes, chronic chest pain, cardiovascular screening and risk stratification, pericardial syndromes, intracardiac/pericardial mass, suspected valvular disease cardiomyopathy, aorta, venous thrombosis, and peripheral vascular disease.

Necrotizing fasciitis resembled acute coronary syndrome: A case report

Chest pain is a frequent complaint in emergency departments, with various differential diagnoses from benign to life-threatening. Hereby, we described a 60-year-old man presented with chest pain and hypotension who initially misdiagnosed as acute coronary syndrome, but was ultimately diagnosed with necrotizing fasciitis. This case highlights the importance of considering rare causes of chest pain.

Coronary Atherosclerosis Progression Provides Incremental Prognostic Value and Optimizes Risk Reclassification by Computed Tomography Angiography

PURPOSE

This study investigated the prognostic value and risk reclassification ability of coronary atherosclerosis progression through serial coronary computed tomography angiography (CCTA).

MATERIALS AND METHODS

This study enrolled patients with suspected or confirmed coronary artery disease who underwent serial CCTA. Coronary atherosclerosis progression was represented by coronary artery calcium score (CACS) and segment stenosis score (SSS) progression. The baseline and follow-up CCTA characteristics and coronary atherosclerosis progression were compared. Furthermore, the incremental prognostic value and reclassification ability of three models (model 1, baseline risk factors; model 2, model 1 + SSS; and model 3, model 2 + SSS progression) for major adverse cardiovascular events (MACEs) were compared.

RESULTS

In total, 516 patients (aged 56.40 ± 9.56 y, 67.4% men) were enrolled. During a mean follow-up of 65.29 months, 114 MACE occurred. The MACE group exhibited higher CACS and SSS than the non-MACE group at baseline and follow-up CCTA ( P < 0.001), and demonstrated higher coronary atherosclerosis progression than the non-MACE group (ΔSSS: 2.63 ± 2.50 vs 1.06 ± 1.78, P < 0.001; ΔCACS: 115.15 ± 186.66 vs 89.91 ± 173.08, P = 0.019). SSS progression provided additional prognostic information (C-index = 0.757 vs 0.715, P < 0.001; integrated discrimination index = 0.066, P < 0.001) and improved the reclassification ability of risk (categorical-net reclassification index = 0.149, P = 0.015) compared with model 2.

CONCLUSIONS

Coronary atherosclerosis progression through CCTA significantly increased the prognostic value and risk stratification for MACE compared with baseline risk factor evaluation and CCTA only.

A patient-centric chest pain management approach utilizing a high sensitivity Troponin-I assay

Objective

The purpose of this study was to assess the impact of adoption of a new cardiac chest pain pathway that included hs-cTnI in the emergency department (ED) when evaluating chest pain patients.

Methods

A new pathway incorporating both hs-cTnI testing (Seimens Healthineers Atellica) and risk stratification tools was developed. The impact of the new algorithm was assessed through a retrospective observational review of patients admitted to the ED with chest pain before implementation and after implementation. Before implementation, the conventional Seimens troponin Vista assay was utilized without a defined algorithmic approach. Bivariate analyses were performed comparing the time periods to determine differences in patient discharge dispositions, length of stay, outcomes, and rate of diagnostic cardiac catheterization.

Results

The proportion of patients discharged from the ED increased while the proportion of patients placed in observation or admitted as in-patient decreased. Variation amongst providers regarding patient disposition decreased. The stress testing rate of patients placed in observation decreased over baseline. There was no change in 30-day MACE rate, but there was a decrease in 30-day MI rate.

Conclusions

The new standardized hs-cTnI algorithm approach is safe as demonstrated by no change in 30-day MACE and is also more appropriate and efficient for patients presenting to the ED with chest pain compared to the non-standardized approach with cTnI used previously.

Coronary Plaque Radiomic Phenotypes Predict Fatal or Nonfatal Myocardial Infarction: Analysis of the SCOT-HEART Trial

BACKGROUND

Coronary computed tomography (CT) angiography-derived attenuation-based plaque burden assessments can identify patients at risk of myocardial infarction.

OBJECTIVES

This study sought to assess whether more detailed plaque morphology assessment using patient-based radiomic characterization could further enhance the identification of patients at risk of myocardial infarction during long-term follow-up.

METHODS

Post hoc analysis of coronary CT angiography was performed within the SCOT-HEART (Scottish Computed Tomography of the HEART) clinical trial. Coronary plaque segmentations were used to calculate plaque burdens and eigen radiomic features that described plaque morphology. Univariable and multivariable Cox proportional hazard models were used to evaluate the association between clinical and image-based features and fatal or nonfatal myocardial infarction, whereas Harrell's C-statistic and cumulative/dynamic area under the curve (AUC) values with cross-validation were used to evaluate prognostic performance.

RESULTS

Scans from 1,750 patients (aged 58 ± 9 years; 56% male) were analyzed. Over a median of 8.6 years of follow-up, 82 patients had a fatal or nonfatal myocardial infarction. Among the eigen radiomic features, 15 were associated with myocardial infarction in univariable analysis, and 8 features retained their association following adjustment for cardiovascular risk score and plaque burden metrics. Adding plaque burden metrics to a clinical model incorporating cardiovascular risk score, Agatston score and presence of obstructive coronary artery disease had similar prediction performance (C-statistic 0.70 vs 0.70), whereas further addition of eigen radiomic features improved model performance (C-statistic 0.74). In temporal analysis, the model including eigen radiomic features had higher cumulative/dynamic AUC values following the fifth year of follow-up.

CONCLUSIONS

Radiomics-based precision phenotyping of coronary plaque morphology provided improvements to long-term prediction of myocardial infarction by CT angiography over and above clinical factors and plaque burden. (Scottish Computed Tomography of the HEART [SCOT-HEART]; NCT01149590).

Aspirin Hypersensitivity in Patients With Atherosclerotic Cardiovascular Disease

Low-dose aspirin remains the most commonly used antiplatelet agent among patients with atherosclerotic cardiovascular disease. Aspirin hypersensitivity occurs in 1% to 5% of patients and is among the most frequent causes for prohibiting the use of aspirin, posing a significant dilemma on how to manage these patients in clinical practice. Aspirin hypersensitivity is often misinterpreted and confused with aspirin intolerance, with treatment approaches being often unclear and lacking specific recommendations. Aspirin desensitization and low-dose aspirin challenge have emerged as pragmatic, effective, and safe approaches in patients with suspected or confirmed aspirin hypersensitivity who require aspirin therapy, but they are underused systematically in clinical practice. Furthermore, there is confusion over alternative antiplatelet agents to be used in these patients. The pathophysiological mechanisms and classification of aspirin hypersensitivity, as well as alternative strategies and practical algorithms to overcome the need for aspirin use in patients with atherosclerotic cardiovascular disease with suspected aspirin hypersensitivity, are discussed.

Diagnostic Performance and Clinical Impact of Photon-Counting Detector Computed Tomography in Coronary Artery Disease

BACKGROUND

Photon-counting detector-computed tomography (PCD-CT) has emerged as a promising technology, offering improved spatial resolution.

OBJECTIVES

This study aimed to evaluate the clinical impact and diagnostic performance of PCD-CT vs conventional energy-integrating detector computed tomography (EID-CT) for obstructive coronary artery disease (CAD).

METHODS

From 2022 to 2023, we retrospectively identified 7,833 consecutive patients who underwent clinically indicated coronary computed tomography angiography (CCTA) at a single center, with either PCD-CT (n = 3,876; NAEOTOM Alpha [Siemens Healthineers]) or EID-CT (n = 3,957; Revolution Apex 256 [GE HealthCare] or Aquilion ONE ViSION 320 [Canon Medical Systems]) scanners. Subsequent invasive coronary angiography (ICA) and percutaneous or surgical revascularization were performed as part of routine clinical care. Among those referred for ICA after coronary CTA, the presence of obstructive CAD in each vessel was determined by coronary CTA (severe stenosis on visual assessment per the Coronary Artery Disease Reporting and Data System) and ICA (≥50% diameter stenosis on quantitative coronary angiography) in a blinded fashion. The diagnostic performance of EID-CT and PCD-CT was compared by using quantitative coronary angiography as the reference standard.

RESULTS

Patients who underwent PCD-CT were less frequently referred to subsequent ICA than those undergoing EID-CT (9.9% vs 13.1%; P < 0.001). Among those who underwent ICA, revascularization was more frequently performed in the PCD-CT group than in the EID-CT group (43.4% vs 35.5%; P = 0.02). In the vessel-level analysis (n = 1,686), specificity (98.0% vs 93.0%; P < 0.001), positive predictive value (83.3% vs 63.0%; P = 0.002), and diagnostic accuracy (97.2% vs 92.8%; P < 0.001) were improved by PCD-CT. Sensitivity (90.9% vs 90.7%; P = 0.95) and negative predictive value (98.9% vs 98.7%; P = 0.83) for obstructive CAD were similar between the PCD-CT and EID-CT groups, respectively.

CONCLUSIONS

PCD-CT exhibited excellent diagnostic performance for detecting obstructive CAD. Compared with patients undergoing conventional EID-CT, fewer patients were referred to ICA after PCD-CT, but those referred were more likely to undergo revascularization.

Exploration of the relationship between general health-related problems and subclinical coronary artery disease: a cross-sectional study in a general population

OBJECTIVE

To explore associations between general health-related problems and subclinical coronary artery disease (CAD), determined by CT coronary calcium score (CT-CCS), in a general population.

DESIGN

A cross-sectional design.

SETTING

This study was performed in a prospective population-based cohort, examining the health and health-related behaviour of individuals living in the Northern Netherlands.

PARTICIPANTS

The initial cohort comprised 6763 participants ≥45 years of age who underwent CT-scanning. Participants were included for the current analysis if they filled in three validated questionnaires (Symptomatic Checklist-90, Research and Development Survey-36 and Reviving the Early Diagnosis of CardioVascular Diseases questionnaire (RED-CVD)) and did not have a history of cardiovascular disease. The final analysis included 6530 participants.

PRIMARY OUTCOME MEASURE

Backward-stepwise and forward-stepwise logistic regression analyses were performed to determine associations between general health-related problems and subclinical CAD (CCS≥100 and ≥300).

RESULTS

The median age was 53 years (25th, 75th percentile: 48, 58); 57% were women. CRCS≥100 was found in 1236 (19%) participants, 437 (12%) in women and 799 (29%) men and CCS≥300 in 643 (9.9%) participants of which 180 (4.8%) were women and 463 (16.6%) men. In univariate analysis, in women the expectation of health to worsen (OR=1.13, 95% CI: 1.05 to 1.21), and in men reduced exercise intolerance (OR=1.14, 95% CI: 1.06 to 1.23) were associated with CCS≥100. The total RED-CVD score in women (OR=1.06, (95% CI: 1.05 to 1.08) and men (OR=1.07, 95% CI: 1.06 to 1.09), and in men also reduced exercise intolerance (OR=1.15, 95% CI: 1.06 to 1.25) and headache (OR=0.55, 95% CI: 0.38 to 0.79) were associated with CCS≥300. In multivariate analyses, only general health expectation in women was still significantly associated with subclinical CAD (CCS≥300) (OR=1.92, 95% CI: 1.56 to 2.37).

CONCLUSION

Only a few general health-related problems were associated with the presence of subclinical CAD in the general population, however, these problems showed no strong association. Therefore, using health-related symptoms does not seem useful to pre-select for CT-CCS.

TRIAL REGISTRATION NUMBER

CCMO Register, NL17981.042.07 and NL58592.042.16.

Temporal trend and regional disparity in the investigations for stable chest pain in Europe: An insight from the PIONEER IV trial

Coronary CT angiography (CCTA) and fractional flow reserve with CCTA (FFRCT) have been endorsed by the ACC/AHA Chest Pain guidelines to streamline the diagnosis of coronary artery disease (CAD), but there is still a significant lack of adherence. In our study of 673 stable chest patients without known CAD from 5 European countries, we found that CCTA is the most common noninvasive diagnostic test, but nearly 40 ​% of them still underwent upfront CAD. Additionally, there was no temporal improvement trend, and the integration of FFRCT is low. We highlighted the urgent need to improve diagnostic processes and update reimbursement policies.

High-Sensitivity Troponin: Finding a Meaningful Delta

High-sensitivity cardiac troponin (hs-cTn) assays have significantly refined the resolution of biomarker-level detection and have emerged as the gold standard cardiac biomarker in evaluating myocardial injury. Since its introduction, hs-cTn has been integrated into the Fourth Universal Definition of Myocardial Infarction and various European Society of Cardiology (ESC) and American College of Cardiology/American Heart Association (ACC/AHA) guidelines for the evaluation and diagnosis of chest pain syndromes. However, despite its integral role in caring for patients with chest pain, there are still substantive gaps in our knowledge of the clinical interpretation of dynamic changes in hs-cTn values. Whether a relative or absolute hs-cTn delta should be used to detect acute myocardial injury remains debatable. There are also emerging considerations of possible sex and racial/ethnic differences in clinically significant troponin deltas. In the emergency department, there is debate about the optimal time frame to recheck hs-cTn after symptom onset for myocardial infarction rule-out and whether hs-cTn deltas should be integrated into clinical risk scores. In this review, we will provide an overview of the history of clinical utilization of cardiac biomarkers, the development of hs-cTn assays, and the ongoing search for a meaningful delta that can be clinically applicable.

Evaluating artificial intelligence-driven stress echocardiography analysis system (EASE study): A mixed method study

INTRODUCTION

The use and value of artificial intelligence (AI)-driven tools and techniques are under investigation in detecting coronary artery disease (CAD). EchoGo Pro is a patented AI-driven stress echocardiography analysis system produced by Ultromics Ltd. (henceforth Ultromics) to support clinicians in detecting cardiac ischaemia and potential CAD. This manuscript presents the research protocol for a field study to independently evaluate the accuracy, acceptability, implementation barriers, users' experience and willingness to pay, cost-effectiveness and value of EchoGo Pro.

METHODS AND ANALYSIS

The 'Evaluating AI-driven stress echocardiography analysis system' (EASE) study is a mixed-method evaluation, which will be conducted in five work packages (WPs). In WP1, we will examine the diagnostic accuracy by comparing test reports generated by EchoGo Pro and three manual raters. In WP2, we will focus on interviewing clinicians, innovation/transformation staff, and patients within the National Health Service (NHS), and staff within Ultromics, to assess the acceptability of this technology. In this WP, we will determine convergence and divergence between EchoGo Pro recommendations and cardiologists' interpretations and will assess what profile of cases is linked with convergence and divergence between EchoGo Pro recommendations and cardiologists' interpretations and how these link to outcomes. In WP4, we will conduct a quantitative cross-sectional survey of trust in AI tools applied to cardiac care settings among clinicians, healthcare commissioners and the general public. Lastly, in WP5, we will estimate the cost of deploying the EchoGo Pro technology, cost-effectiveness and willingness to pay cardiologists, healthcare commissioners and the general public. The results of this evaluation will support evidence-informed decision-making around the widespread adoption of EchoGo Pro and similar technologies in the NHS and other health systems.

ETHICS APPROVAL AND DISSEMINATION

This research has been approved by the NHS Health Research Authority (IRAS No: 315284) and the London South Bank University Ethics Panel (ETH2223-0164). Alongside journal publications, we will disseminate study methods and findings in conferences, seminars and social media. We will produce additional outputs in appropriate forms, for example, research summaries and policy briefs, for diverse audiences in NHS.

Non-Invasive Assessment of Coronary Microvascular Dysfunction Using Vascular Deformation-Based Flow Estimation

OBJECTIVE

Non-invasive computation of the index of microcirculatory resistance from coronary computed tomography angiography (CTA), referred to as IMR[Formula: see text], is a promising approach for quantitative assessment of coronary microvascular dysfunction (CMD). However, the computation of IMR[Formula: see text] remains an important unresolved problem due to its high requirement for the accuracy of coronary blood flow. Existing CTA-based methods for estimating coronary blood flow rely on physiological assumption models to indirectly identify, which leads to inadequate personalization of total and vessel-specific flow.

METHODS

To overcome this challenge, we propose a vascular deformation-based flow estimation (VDFE) model to directly estimate coronary blood flow for reliable IMR[Formula: see text] computation. Specifically, we extract the vascular deformation of each vascular segment from multi-phase CTA. The concept of inverse problem solving is applied to implicitly derive coronary blood flow based on the physical constraint relationship between blood flow and vascular deformation. The vascular deformation constraints imposed on each segment within the vascular structure ensure sufficient individualization of coronary blood flow.

RESULTS

Experimental studies on 106 vessels collected from 89 subjects demonstrate the validity of our VDFE, achieving an IMR[Formula: see text] accuracy of 82.08 %. The coronary blood flow estimated by VDFE has better reliability than the other four existing methods.

CONCLUSION

Our proposed VDFE is an effective approach to non-invasively compute IMR[Formula: see text] with excellent diagnostic performance.

SIGNIFICANCE

The VDFE has the potential to serve as a safe, effective, and cost-effective clinical tool for guiding CMD clinical treatment and assessing prognosis.

Clinical Advances in Cardiovascular Computed Tomography: From Present Applications to Promising Developments

PURPOSE OF THE REVIEW

This review aims to provide a profound overview on most recent studies on the clinical significance of Cardiovascular Computed Tomography (CCT) in diagnostic and therapeutic pathways. Herby, this review helps to pave the way for a more extended but yet purposefully use in modern day cardiovascular medicine.

RECENT FINDINGS

In recent years, new clinical applications of CCT have emerged. Major applications include the assessment of coronary artery disease and structural heart disease, with corresponding recommendations by major guidelines of international societies. While CCT already allows for a rapid and non-invasive diagnosis, technical improvements enable further in-depth assessments using novel imaging parameters with high temporal and spatial resolution. Those developments facilitate diagnostic and therapeutic decision-making as well as improved prognostication. This review determined that recent advancements in both hardware and software components of CCT allow for highly advanced examinations with little radiation exposure. This particularly strengthens its role in preventive care and coronary artery disease. The addition of functional analyses within and beyond coronary artery disease offers solutions in wide-ranging patient populations. Many techniques still require improvement and validation, however, CCT possesses potential to become a "one-stop-shop" examination.

Systematic hand-held echocardiography in patients hospitalized with acute coronary syndrome

AIMS

Transthoracic echocardiography is recommended in all patients with acute coronary syndrome but is time-consuming and lacks an evidence base. We aimed to assess the feasibility, diagnostic accuracy, and time efficiency of hand-held echocardiography in patients with acute coronary syndrome and describe the impact of echocardiography on clinical management in this setting.

METHODS AND RESULTS

Patients with acute coronary syndrome underwent both hand-held and transthoracic echocardiographies with agreement between key imaging parameters assessed using kappa statistics. The immediate clinical impact of hand-held echocardiography in this population was systematically evaluated. Overall, 262 patients (65 ± 12 years, 71% male) participated. Agreement between hand-held and transthoracic echocardiographies was good-to-excellent (kappa 0.60-1.00) with hand-held echocardiography having an overall negative predictive value of 95%. Hand-held echocardiography was performed rapidly (7.7 ± 1.6 min) and completed a median of 5 (interquartile range 3-20) h earlier than transthoracic echocardiography. Systematic hand-held echocardiography in all patients with acute coronary syndrome identified an important cardiac abnormality in 50%, and the clinical management plan was changed by echocardiography in 42%. In 85% of cases, hand-held echocardiography was sufficient for patient decision-making, and transthoracic echocardiography was no longer deemed necessary.

CONCLUSION

In patients with acute coronary syndrome, hand-held echocardiography provides comparable results to transthoracic echocardiography, can be more rapidly applied, and gives sufficient imaging information for decision-making in the vast majority of patients. Systematic echocardiography has clinical impact in half of patients, supporting the clinical utility of echocardiography in this population and providing an evidence base for current guidelines.

Multimodality imaging for the evaluation and management of patients with long-term (durable) left ventricular assist devices

Left ventricular assist devices (LVADs) are gaining increasing importance as therapeutic strategy in advanced heart failure (HF), not only as bridge to recovery or to transplant but also as destination therapy. Even though long-term LVADs are considered a precious resource to expand the treatment options and improve clinical outcome of these patients, these are limited by peri-operative and post-operative complications, such as device-related infections, haemocompatibility-related events, device mis-positioning, and right ventricular failure. For this reason, a precise pre-operative, peri-operative, and post-operative evaluation of these patients is crucial for the selection of LVAD candidates and the management LVAD recipients. The use of different imaging modalities offers important information to complete the study of patients with LVADs in each phase of their assessment, with peculiar advantages/disadvantages, ideal application, and reference parameters for each modality. This clinical consensus statement sought to guide the use of multimodality imaging for the evaluation of patients with advanced HF undergoing LVAD implantation.

Coronary Artery Anomalies: Diagnosis & Management

Coronary artery anomalies encompass a spectrum of congenital abnormalities affecting the origin, course, or termination of the major epicardial coronary arteries. Despite their rarity, coronary artery anomalies represent a significant burden on cardiovascular health due to their potential to disrupt myocardial blood flow and precipitate adverse cardiac events. While historically diagnosed postmortem, the widespread availability of imaging modalities has led to an increased recognition of coronary artery anomalies, particularly in adults. This review synthesizes current knowledge on the classification, mechanisms, and clinical implications of coronary anomalies, focusing on prevalent variants with significant clinical impact. We discuss strategies for medical and surgical management, as well as contemporary screening recommendations, acknowledging the evolving understanding of these anomalies. Given the breadth of possible variants and the limited data on some presentations, this review provides a framework to aid clinicians in the recognition and management of coronary anomalies, with a particular emphasis on their stratification by anatomical location. By consolidating existing knowledge and highlighting areas of uncertainty, this review aims to enhance clinical decision-making and improve outcomes for individuals with coronary anomalies.

Spontaneous Coronary Artery Dissection Without Myocardial Infarction

Spontaneous coronary artery dissection (SCAD) is an increasingly recognized cause of acute myocardial infarction. We examine 4 atypical presentations of SCAD. These cases highlight treatment course and outcomes for patients with SCAD who do not present with acute coronary syndrome.

Sex-specific high-sensitivity troponin T cut-points have similar safety but lower efficacy than overall cut-points in a multisite U.S. cohort

BACKGROUND

Data comparing the performance of sex-specific to overall (non-sex-specific) high-sensitivity cardiac troponin (hs-cTn) cut-points for diagnosing acute coronary syndrome (ACS) are limited. This study aims to compare the safety and efficacy of sex-specific versus overall 99th percentile high-sensitivity cardiac troponin T (hs-cTnT) cut-points.

METHODS

We conducted a secondary analysis of the STOP-CP cohort, which prospectively enrolled emergency department patients ≥ 21 years old with symptoms suggestive of ACS without ST-elevation on initial electrocardiogram across eight U.S. sites (January 25, 2017-September 6, 2018). Participants with both 0- and 1-h hs-cTnT measures less than or equal to the 99th percentile (sex-specific 22 ng/L for males, 14 ng/L for females; overall 19 ng/L) were classified into the rule-out group. The safety outcome was adjudicated cardiac death or myocardial infarction (MI) at 30 days. Efficacy was defined as the proportion classified to the rule-out group. McNemar's test and a generalized score statistic were used to compare rule-out and 30-day cardiac death or MI rates between strategies. Net reclassification improvement (NRI) index was used to further compare performance.

RESULTS

This analysis included 1430 patients, of whom 45.8% (655/1430) were female; the mean ± SD age was 57.6 ± 12.8 years. At 30 days, cardiac death or MI occurred in 12.8% (183/1430). The rule-out rate was lower using sex-specific versus overall cut-points (70.6% [1010/1430] vs. 72.5% [1037/1430]; p = 0.003). Among rule-out patients, the 30-day cardiac death or MI rates were similar for sex-specific (2.4% [24/1010]) vs. overall (2.3% [24/1037]) strategies (p = 0.79). Among patients with cardiac death or MI, sex-specific versus overall cut-points correctly reclassified three females and incorrectly reclassified three males. The sex-specific strategy resulted in a net of 27 patients being incorrectly reclassified into the rule-in group. This led to an NRI of -2.2% (95% CI -5.1% to 0.8%).

CONCLUSIONS

Sex-specific hs-cTnT cut-points resulted in fewer patients being ruled out without an improvement in safety compared to the overall cut-point strategy.

Machine-Learning for Phenotyping and Prognostication of Myocardial Infarction and Injury in Suspected Acute Coronary Syndrome

Background

Clinical work-up for suspected acute coronary syndrome (ACS) is resource intensive.

Objectives

This study aimed to develop a machine learning model for digitally phenotyping myocardial injury and infarction and predict 30-day events in suspected ACS patients.

Methods

Training and testing data sets, predominantly derived from electronic health records, included suspected ACS patients presenting to 6 and 26 South Australian hospitals, respectively. All index presentations and 30-day death and myocardial infarction (MI) were adjudicated using the Fourth Universal Definition of MI. We developed 2 diagnostic prediction models which phenotype myocardial injury and infarction according to the Fourth UDMI (chronic myocardial injury vs acute myocardial injury patterns, the latter further differentiated into acute non-ischaemic myocardial injury, Types 1 and 2 MI) using eXtreme Gradient Boosting (XGB) and deep-learning (DL). We also developed an event prediction model for risk prediction of 30-day death or MI using XGB. Analyses were performed in Python 3.6.

Results

The training and testing data sets had 6,722 and 8,869 participants, respectively. The diagnostic prediction XGB and deep learning models achieved an area under the curve of 99.2% ± 0.1% and 98.8% ± 0.2%, respectively, for differentiating an acute myocardial injury pattern from no injury or chronic myocardial injury pattern and achieved 95.5% ± 0.2% and 94.6% ± 0.9%, respectively, for differentiating type 1 MI from type 2 MI or acute nonischemic myocardial injury. The 30-day death/MI event prediction model achieved an area under the curve of 88.5% ± 0.5%.

Conclusions

Machine learning models can digitally phenotype suspected ACS patients at index presentation and predict subsequent events within 30 days. These models require external validation in a randomized clinical trial to evaluate their impact in clinical practice.

Prevalence of Coronary Vasomotor Disorders in Patients With Angina and Nonobstructive Coronary Arteries: A Sydney Experience

BACKGROUND

Patients with angina and non-obstructive coronary arteries (ANOCA) frequently have coronary vasomotor disorders (CVaD), characterised by transient pathological vasoconstriction and/or impaired microvascular vasodilatation. Functional coronary angiography is the gold standard for diagnosing CVaD. Despite recommendations, testing is only available at a limited number of Australian and New Zealand centres. This study aimed to determine the prevalence of CVaDs in an Australian ANOCA population and identify predictive factors associated with specific endotypes.

METHOD

Functional coronary angiography was performed in patients with suspected ANOCA. Vasoreactivity testing was performed using intracoronary acetylcholine provocation. A pressure-temperature sensor guidewire was used for coronary physiology assessment. Comprehensive clinical data on patient characteristics, cardiac risk factors, and symptom profiles was collected before testing.

RESULTS

This prospective observational study at Royal Prince Alfred and Concord Repatriation General Hospital included 110 patients (58±13 years with 63.6% women), with 81.8% (90/110) having a CVaD. Regarding specific ANOCA endotypes, microvascular angina (MVA) occurred in 31.8% (35/110) of cases, vasospastic angina (VSA) in 25.5% (28/110) and a mixed presentation of MVA and VSA in 24.5% (27/110) of patients. Patients with CVaD were found to be older (59±11 vs 51±15, p=0.024), overweight (61.1% vs 15.0%, p<0.001) and had a worse quality of life (EuroQol 5 Dimensions-5 Levels; 0.61 vs 0.67, p=0.043). MVA was associated with being overweight (odds ratio [OR] 4.2 [95% confidence interval [CI] 1.9-9.3]; p=0.015) and ischaemia on stress testing (OR 2.4 [95% CI 1.1-4.3]; p=0.028), while VSA was associated with smoking (OR 9.1 [95% CI 2.21-39.3]; p=0.007).

CONCLUSIONS

Coronary vasomotor disorders are highly prevalent among ANOCA patients. This study highlights the importance of increasing national awareness and the use of functional coronary angiography to evaluate and manage this unique cohort.

Late Outcomes of Patients in the Emergency Department With Acute Chest Pain Evaluated With Computed Tomography-Derived Fractional Flow Reserve

Computed tomography (CTA)-derived fractional flow reserve (FFRCT) guides the need for invasive coronary angiography (ICA). Late outcomes after FFRCT are reported in stable ischemic heart disease but not in acute chest pain in the emergency department (ACP-ED). The objectives are to assess the risk of death, myocardial infarction (MI), revascularization, and ICA after FFRCT. From 2015 to 2018, 389 low-risk patients with ACP-ED (negative biomarkers, no electrocardiographic ischemia) underwent CTA and FFRCT and were entered into a prospective institutional registry; patients were followed up for 41 ± 10 months. CTA stenosis ≥50% was present in 81% of the patients. Positive (FFRCT ≤0.80) and negative FFRCT were observed in 124 (32%) and 265 patients (68%), respectively. ICA was performed in 108 of 124 patients (87%) with positive FFRCT and 89 of 265 patients (34%) with negative FFRCT (p <0.00001). Revascularization was performed in 87 of 124 (70%) patients with positive FFRCT and in 22 of 265 (8%) with negative FFRCT (p <0.00001). Appropriateness of revascularization was established by blinded adjudication of ICA and invasive FFR using practice guidelines; revascularization was appropriate in 81 of 124 (65%) and 6 of 265 (2%) of FFRCT-positive and -negative patients, respectively (p <0.00001). At follow-up, for patients with positive versus negative FFRCT, the rates were 0.8% versus 0% for death (p = 0.32) and 1.6% versus 0.4% for MI (p = 0.24). In conclusion, in low-risk patients with ACP-ED who underwent CTA and FFRCT, the risk of late death (0.2%) and MI (0.7%) are low. Negative FFRCT is associated with excellent long-term prognosis, and positive FFRCT predicts obstructive disease requiring revascularization. FFRCT can safely triage patients with ACP-ED and reduce unnecessary ICA and revascularization.

Long-acting cilostazol versus isosorbide mononitrate for patients with vasospastic angina: a randomized controlled trial

BACKGROUND

Cilostazol has a vasodilatory function that may be beneficial for patients with vasospastic angina (VSA). We conducted a randomized, open-label, controlled trial to compare the efficacy and safety of long-acting cilostazol and isosorbide mononitrate (ISMN) for VSA.

METHODS

The study included patients with confirmed VSA between September 2019 and May 2021. Participants were randomly assigned to receive long-acting cilostazol (test group, 200 mg once daily) or conventional ISMN therapy (control group, 20 mg twice daily) for 4 weeks. The clinical efficacy and safety were evaluated using weekly questionnaires.

RESULTS

Forty patients were enrolled in the study (long-acting cilostazol, n  = 20; ISMN, n  = 20). Baseline characteristics were balanced between the two groups. Long acting cilostazol showed better angina symptom control within the first week compared to ISMN [reduction of pain intensity score, 6.0 (4.0-8.0) vs. 4.0 (1.0-5.0), P  = 0.005; frequency of angina symptom, 0 (0-2.0) vs. 2.0 (0-3.0), P  = 0.027, respectively]. The rate of neurological adverse reactions was lower in the cilostazol group than in the ISMN group (headache or dizziness, 40 vs. 85%, P  = 0.009; headache, 30 vs. 70%, P  = 0.027).

CONCLUSION

Long-acting cilostazol provided comparable control of angina and fewer adverse neurologic reactions within 4 weeks compared to ISMN. Long-acting cilostazol provides more intensive control of angina within 1 week, suggesting that it may be an initial choice for the treatment of VSA.

Patient satisfaction with coronary CT angiography versus invasive coronary angiography: results of a single-center randomized trial

OBJECTIVE

Because there is evidence for a clinical benefit of using coronary computed tomography (CT) angiography instead of invasive coronary angiography (ICA) in patients with suspected coronary artery disease (CAD), we ascertained if patient satisfaction could represent an important barrier to implementation of coronary CT in clinical practice.

MATERIALS AND METHODS

A total of 329 patients with suspected CAD and clinical indication for ICA were randomly assigned to undergo either CT or ICA for guiding treatment. Satisfaction for both groups was assessed by patient questionnaire completed twice, ≥24 h after CT or ICA, and at follow-up after a median of 3.7 years. Assessment included preparation, concern, comfort, helplessness, pain, willingness to undergo tests again, overall satisfaction, and preference. Pearson's chi-square test and Wilcoxon rank-sum test were used.

RESULTS

Overall, 91% of patients undergoing CT (152/167) and 86% undergoing ICA completed assessment (140/162, p = 0.19). Patients reported being significantly better prepared for CT, less concerned about the test, and felt less helpless than during ICA (all: p < 0.001). Subjective pain (horizontal nonmarked visual analogue scale) was significantly lower for CT (6.9 ± 14.7) than for ICA (17.1 ± 22.7; p < 0.001). At follow-up, significantly more patients in the CT group reported very good satisfaction with communication of findings compared with the ICA group (p < 0.001) and 92% would recommend the institution to someone referred for the same examination.

CONCLUSIONS

Results from our single-center randomized study show very good satisfaction with coronary CT compared to ICA. Thus, superior acceptance of CT should be considered in shared decision-making.

CLINICAL RELEVANCE STATEMENT

This evaluation of patient satisfaction in a randomized study shows that patients' preference is in line with the clinical benefit provided by CT and also suggests to prefer a CT-first strategy in suspected coronary artery disease.

KEY POINTS

• Subjective pain was significantly lower for coronary CT angiography than for invasive coronary angiography and patients felt better prepared and less concerned about CT. • Patients were overall more satisfied with coronary CT angiography than invasive coronary angiography in a randomized controlled trial. • After a median follow-up of 3.7 years, more patients in the CT group indicated very good satisfaction with the communication of findings and with the examination itself.

Machine learning-based coronary artery calcium score predicted from clinical variables as a prognostic indicator in patients referred for invasive coronary angiography

OBJECTIVES

Utilising readily available clinical variables, we aimed to develop and validate a novel machine learning (ML) model to predict severe coronary calcification, and further assessed its prognostic significance.

METHODS

This retrospective study enrolled patients who underwent coronary CT angiography and subsequent invasive coronary angiography. Multiple ML algorithms were used to train the models for predicting severe coronary calcification (cardiac CT-measured coronary artery calcium [CT-CAC] score ≥ 400). The ML-based CAC (ML-CAC) score derived from the ML predictive probability was stratified into quartiles for prognostic analysis. The primary endpoint was a composite of all-cause death, nonfatal myocardial infarction, or nonfatal stroke.

RESULTS

Overall, 5785 patients were divided into training (80%) and test sets (20%). For clinical practicability, we selected the nine-feature support vector machine model with good and satisfactory performance regarding both discrimination and calibration based on five repetitions of the 10-fold cross-validation in the training set (mean AUC = 0.715, Brier score = 0.202), and based on the test in the test set (AUC = 0.753, Brier score = 0.191). In the test set cohort (n = 1137), the primary endpoint was observed in 50 (4.4%) patients during a median 2.8 years' follow-up. The ML-CAC system was significantly associated with an increased risk of the primary endpoint (adjusted hazard ratio for trend 2.26, 95% CI 1.35-3.79, p = 0.002). There was no significant difference in the prognostic value between the ML-CAC and CT-CAC systems (C-index, 0.67 vs. 0.69; p = 0.618).

CONCLUSION

ML-CAC score predicted from clinical variables can serve as a novel prognostic indicator in patients referred for invasive coronary angiography.

CLINICAL RELEVANCE STATEMENT

In patients referred for invasive coronary angiography who have not undergone preoperative CT-measured coronary artery calcium scoring, machine learning-based coronary artery calcium score assessment can serve as an alternative for predicting the prognosis.

KEY POINTS

• The coronary artery calcium (CAC) score, a solid prognostic indicator, can be predicted using non-CT methods. • We developed a machine learning (ML)-CAC model utilising nine clinical variables to predict severe coronary calcification. • The ML-CAC system offers significant prognostic value in patients referred for invasive coronary angiography.

Optimal timing of revascularization for patients with non-ST segment elevation myocardial infarction and severe left ventricular dysfunction

Optimal timing of revascularization for patients who presented with non-ST segment elevation myocardial infarction (NSTEMI) and severe left ventricular (LV) dysfunction is unclear. A total of 386 NSTEMI patients with severe LV dysfunction from the nationwide, multicenter, and prospective Korea Acute Myocardial Infarction Registry V (KAMIR-V) were enrolled. Severe LV dysfunction was defined as LV ejection fraction ≤ 35%. Patients with cardiogenic shock were excluded. Patients were stratified into two groups: PCI within 24 hours (early invasive group) and PCI over 24 hours (selective invasive group). Primary endpoint was major adverse cardiac and cerebrovascular events (MACCE) including all-cause death, non-fatal MI, repeat revascularization, and stroke at 12 months after index procedure. Early invasive group showed higher incidence of in-hospital death (9.4% vs 3.3%, P = .036) and cardiogenic shock (11.5% vs 4.6%, P = .030) after PCI. Early invasive group also showed higher maximum troponin I level during admission (27.7 ± 44.8 ng/mL vs 14.9 ± 24.6 ng/mL, P = .001), compared with the selective invasive group. Early invasive group had an increased risk of 12-month MACCE, compared with selective invasive group (25.6% vs 17.1%; adjusted HR = 2.10, 95% CI 1.17-3.77, P = .006). Among NSTEMI patients with severe LV dysfunction, the early invasive strategy did not improve the clinical outcomes. This data supports that an individualized approach may benefit high-risk NSTEMI patients rather than a routine invasive approach.

Prospective deep learning-based quantitative assessment of coronary plaque by computed tomography angiography compared with intravascular ultrasound: the REVEALPLAQUE study

AIMS

Coronary computed tomography angiography provides non-invasive assessment of coronary stenosis severity and flow impairment. Automated artificial intelligence (AI) analysis may assist in precise quantification and characterization of coronary atherosclerosis, enabling patient-specific risk determination and management strategies. This multicentre international study compared an automated deep learning-based method for segmenting coronary atherosclerosis in coronary computed tomography angiography (CCTA) against the reference standard of intravascular ultrasound (IVUS).

METHODS AND RESULTS

The study included clinically stable patients with known coronary artery disease from 15 centres in the USA and Japan. An AI-enabled plaque analysis was utilized to quantify and characterize total plaque (TPV), vessel, lumen, calcified plaque (CP), non-calcified plaque (NCP), and low-attenuation plaque (LAP) volumes derived from CCTA and compared with IVUS measurements in a blinded, core laboratory-adjudicated fashion. In 237 patients, 432 lesions were assessed; mean lesion length was 24.5 mm, and mean IVUS-TPV was 186.0 mm3. AI-enabled plaque analysis on CCTA showed strong correlation and high accuracy when compared with IVUS; correlation coefficient, slope, and Y intercept for TPV were 0.91, 0.99, and 1.87, respectively; for CP volume 0.91, 1.05, and 5.32, respectively; and for NCP volume 0.87, 0.98, and 15.24, respectively. Bland-Altman analysis demonstrated strong agreement with little bias for these measurements.

CONCLUSION

AI-enabled CCTA quantification and characterization of atherosclerosis demonstrated strong agreement with IVUS reference standard measurements. This tool may prove effective for accurate evaluation of coronary atherosclerotic burden and cardiovascular risk assessment.

Optimizing Management of Stable Angina: A Patient-Centered Approach Integrating Revascularization, Medical Therapy, and Lifestyle Interventions

Angina pectoris may arise from obstructive coronary artery disease (CAD) or in the absence of significant CAD (ischemia with nonobstructed coronary arteries [INOCA]). Therapeutic strategies for patients with angina and obstructive CAD focus on reducing cardiovascular events and relieving symptoms, whereas in INOCA the focus shifts toward managing functional alterations of the coronary circulation. In obstructive CAD, coronary revascularization might improve angina status, although a significant percentage of patients present angina persistence or recurrence, suggesting the presence of functional mechanisms along with epicardial CAD. In patients with INOCA, performing a precise endotype diagnosis is crucial to allow a tailored therapy targeted toward the specific pathogenic mechanism. In this expert opinion paper, we review the evidence for the management of angina, highlighting the complementary role of coronary revascularization, optimal medical therapy, and lifestyle interventions and underscoring the importance of a personalized approach that targets the underlying pathobiology.

Clinical and Analytical Performance of a Novel Point-of-Care High-Sensitivity Cardiac Troponin I Assay

BACKGROUND

Point-of-care (POC) high-sensitivity cardiac troponin assays may further accelerate the diagnosis of myocardial infarction (MI).

OBJECTIVES

This study sought to assess the clinical and analytical performance of the novel high-sensitivity cardiac troponin I (hs-cTnI)-SPINCHIP POC test.

METHODS

Adult patients presenting with acute chest discomfort to the emergency department were enrolled in an international, diagnostic, multicenter study. The final diagnosis was centrally adjudicated by 2 independent cardiologists using all clinical information. We compared the discriminatory performance of hs-cTnI-SPINCHIP with current established central laboratory assays and derived an assay-specific hs-cTnI-SPINCHIP 0/1-hour algorithm. Secondary analyses included sample type comparisons (whole blood, fresh/frozen plasma, and capillary finger prick) and precision analysis.

RESULTS

MI was the adjudicated final diagnosis in 214 (19%) of 1,102 patients. Area under the receiver-operating characteristic curve was 0.94 (95% CI: 0.92-0.95) for hs-cTnI-SPINCHIP vs 0.94 (95% CI: 0.92-0.95) for hs-cTnI-Architect (P = 0.907) and 0.93 (95% CI: 0.91-0.95) for high-sensitivity cardiac troponin T Elecsys (P = 0.305). A cutoff <7 ng/L at presentation (if chest pain onset was >3 hours) or <7 ng/L together with a 0/1-hour delta of <4 ng/L ruled out 51% with a sensitivity and negative predictive value of 100% (95% CI: 97.7%-100%) and 100% (95% CI: 99.0%-100%), respectively. A hs-cTnI-SPINCHIP concentration ≥36 ng/L or a 0/1-hour delta ≥11 ng/L ruled in 27% with a specificity and positive predictive value of 90.9% (95% CI: 88.3%-92.9%) and 72.9% (95% CI: 66.4%-78.6%), respectively. Bootstrap internal validation confirmed excellent diagnostic performance. High agreement was observed between different sample types.

CONCLUSIONS

The SPINCHIP hs-cTnI POC test has very high diagnostic accuracy. Its assay-specific 0/1-hour algorithm achieved very high sensitivity/negative predictive value and specificity/positive predictive value for rule-out/in MI. (Advantageous Predictors of Acute Coronary Syndromes Evaluation [APACE] Study [APACE]; NCT00470587).

Pre-hospital rule-out of non-ST-segment elevation acute coronary syndrome by a single troponin: final one-year outcomes of the ARTICA randomised trial

BACKGROUND AND AIMS

The healthcare burden of acute chest pain is enormous. In the randomized ARTICA trial, we showed that pre-hospital identification of low-risk patients and rule-out of non-ST-segment elevation acute coronary syndrome (NSTE-ACS) with point-of-care (POC) troponin measurement reduces 30-day healthcare costs with low major adverse cardiac events (MACE) incidence. Here we present the final 1-year results of the ARTICA trial.

METHODS

Low-risk patients with suspected NSTE-ACS were randomized to pre-hospital rule-out with POC troponin measurement or emergency department (ED) transfer. Primary 1-year outcome was healthcare costs. Secondary outcomes were safety, quality of life (QoL), and cost-effectiveness. Safety was defined as a 1-year MACE consisting of ACS, unplanned revascularization, or all-cause death. QoL was measured with EuroQol-5D-5L questionnaires. Cost-effectiveness was defined as 1-year healthcare costs difference per QoL difference.

RESULTS

Follow-up was completed for all 863 patients. Healthcare costs were significantly lower in the pre-hospital strategy (€1932 ± €2784 vs. €2649 ± €2750), mean difference €717 [95% confidence interval (CI) €347 to €1087; P < 0.001]. In the total population, the 1-year MACE rate was comparable between groups [5.1% (22/434) in the pre-hospital strategy vs. 4.2% (18/429) in the ED strategy; P = 0.54]. In the ruled-out ACS population, 1-year MACE remained low [1.7% (7/419) vs. 1.4% (6/417)], risk difference 0.2% (95% CI -1.4% to 1.9%; P = 0.79). QoL showed no significant difference between strategies.

CONCLUSIONS

Pre-hospital rule-out of NSTE-ACS with POC troponin testing in low-risk patients is cost-effective, as expressed by a sustainable healthcare cost reduction and no significant effect on QoL. One-year MACE remained low for both strategies.

Risk scores and coronary artery disease in patients with suspected acute coronary syndrome and intermediate cardiac troponin concentrations

BACKGROUND

Guidelines recommend the use of risk scores to select patients for further investigation after myocardial infarction has been ruled out but their utility to identify those with coronary artery disease is uncertain.

METHODS

In a prospective cohort study, patients with intermediate high-sensitivity cardiac troponin I concentrations (5 ng/L to sex-specific 99th percentile) in whom myocardial infarction was ruled out were enrolled and underwent coronary CT angiography (CCTA) after hospital discharge. History, ECG, Age, Risk factors, Troponin (HEART), Emergency Department Assessment of Chest Pain Score (EDACS), Global Registry of Acute Coronary Event (GRACE), Thrombolysis In Myocardial Infarction (TIMI), Systematic COronary Risk Evaluation 2 and Pooled Cohort Equation risk scores were calculated and the odds ratio (OR) and diagnostic performance for obstructive coronary artery disease were determined using established thresholds.

RESULTS

Of 167 patients enrolled (64±12 years, 28% female), 29.9% (50/167) had obstructive coronary artery disease. The odds of having obstructive disease were increased for all scores with the lowest and highest increase observed for an EDACS score ≥16 (OR 2.2 (1.1-4.6)) and a TIMI risk score ≥1 (OR 12.9 (3.0-56.0)), respectively. The positive predictive value (PPV) was low for all scores but was highest for a GRACE score >88 identifying 39% as high risk with a PPV of 41.9% (30.4-54.2%). The negative predictive value (NPV) varied from 77.3% to 95.2% but was highest for a TIMI score of 0 identifying 26% as low risk with an NPV of 95.2% (87.2-100%).

CONCLUSIONS

In patients with intermediate cardiac troponin concentrations in whom myocardial infarction has been excluded, clinical risk scores can help identify patients with and without coronary artery disease, although the performance of established risk thresholds is suboptimal for utilisation in clinical practice.

TRIAL REGISTRATION NUMBER

NCT04549805.

Serum Magnesium Levels and QTc Interval Prolongation As Prognostic Markers in Acute Myocardial Infarction: A Randomized Controlled Study

Introduction Acute myocardial infarction (AMI) is frequently preceded by arrhythmias, which continue to be a prominent cause of abrupt fatality in AMI. Abnormal magnesium levels have been linked to the emergence of arrhythmia because it enhances myocardial metabolism and cardiac output and prevents calcium buildup and myocardial cell death by lowering arrhythmias. The objectives of this study were to evaluate serum magnesium levels and QTc interval as prognostic indicators in AMI patients during the initial 48 hours of hospital stay and to correlate these parameters with the Global Registry of Acute Coronary Events (GRACE) scoring. We studied AMI patients by dividing them into two groups: those with abnormal and those with normal serum magnesium levels. Methods After obtaining ethical approvals, patients were subjected to detailed history, which included sociodemographic details, drug history, clinical examination, and investigations such as creatine kinase myocardial band (CK-MB), CK-total, troponin-T, ECG (QTc interval), two-dimensional echocardiogram (2D-ECHO), serum creatinine and magnesium levels, heart rate, and blood pressure. We also calculated the GRACE score for all patients. Results We found that patients in the age group of 51-60 years were more prone to developing arrhythmias, and while AMI was more prevalent in males, the occurrence of arrhythmias was slightly higher in females with AMI. Anterior wall motion abnormality (AWMA) was the most predominant abnormality, and 12.3% of AWMA patients had arrhythmias. QTc interval was significantly longer in patients who developed arrhythmias. Interestingly, among patients with QTc prolongation, 35% patients had abnormal magnesium levels, while 65% had normal magnesium levels. In our study, of the 25 patients with hypermagnesemia, nine (36%) developed arrhythmias, while of the 75 patients with hypomagnesemia, 15 (20%) patients developed arrhythmias. Interestingly, we found that there was a positive correlation between GRACE score and serum magnesium as well as QTc interval prolongation. Lastly, among the six deaths reported, three (50%) patients had arrhythmias. Conclusion Overall, we conclude that serum magnesium levels play a pivotal role as a prognostic tool for arrhythmias and are a useful investigation during the initial 48 hours of admission in AMI patients.

Development and Validation of a Quantitative Coronary CT Angiography Model for Diagnosis of Vessel-Specific Coronary Ischemia

BACKGROUND

Noninvasive stress testing is commonly used for detection of coronary ischemia but possesses variable accuracy and may result in excessive health care costs.

OBJECTIVES

This study aimed to derive and validate an artificial intelligence-guided quantitative coronary computed tomography angiography (AI-QCT) model for the diagnosis of coronary ischemia that integrates atherosclerosis and vascular morphology measures (AI-QCTISCHEMIA) and to evaluate its prognostic utility for major adverse cardiovascular events (MACE).

METHODS

A post hoc analysis of the CREDENCE (Computed Tomographic Evaluation of Atherosclerotic Determinants of Myocardial Ischemia) and PACIFIC-1 (Comparison of Coronary Computed Tomography Angiography, Single Photon Emission Computed Tomography [SPECT], Positron Emission Tomography [PET], and Hybrid Imaging for Diagnosis of Ischemic Heart Disease Determined by Fractional Flow Reserve) studies was performed. In both studies, symptomatic patients with suspected stable coronary artery disease had prospectively undergone coronary computed tomography angiography (CTA), myocardial perfusion imaging (MPI), SPECT, or PET, fractional flow reserve by CT (FFRCT), and invasive coronary angiography in conjunction with invasive FFR measurements. The AI-QCTISCHEMIA model was developed in the derivation cohort of the CREDENCE study, and its diagnostic performance for coronary ischemia (FFR ≤0.80) was evaluated in the CREDENCE validation cohort and PACIFIC-1. Its prognostic value was investigated in PACIFIC-1.

RESULTS

In CREDENCE validation (n = 305, age 64.4 ± 9.8 years, 210 [69%] male), the diagnostic performance by area under the receiver-operating characteristics curve (AUC) on per-patient level was 0.80 (95% CI: 0.75-0.85) for AI-QCTISCHEMIA, 0.69 (95% CI: 0.63-0.74; P < 0.001) for FFRCT, and 0.65 (95% CI: 0.59-0.71; P < 0.001) for MPI. In PACIFIC-1 (n = 208, age 58.1 ± 8.7 years, 132 [63%] male), the AUCs were 0.85 (95% CI: 0.79-0.91) for AI-QCTISCHEMIA, 0.78 (95% CI: 0.72-0.84; P = 0.037) for FFRCT, 0.89 (95% CI: 0.84-0.93; P = 0.262) for PET, and 0.72 (95% CI: 0.67-0.78; P < 0.001) for SPECT. Adjusted for clinical risk factors and coronary CTA-determined obstructive stenosis, a positive AI-QCTISCHEMIA test was associated with aHR: 7.6 (95% CI: 1.2-47.0; P = 0.030) for MACE.

CONCLUSIONS

This newly developed coronary CTA-based ischemia model using coronary atherosclerosis and vascular morphology characteristics accurately diagnoses coronary ischemia by invasive FFR and provides robust prognostic utility for MACE beyond presence of stenosis.

Modelled impact of virtual fractional flow reserve in patients undergoing coronary angiography (VIRTU-4)

BACKGROUND

The practical application of 'virtual' (computed) fractional flow reserve (vFFR) based on invasive coronary angiogram (ICA) images is unknown. The objective of this cohort study was to investigate the potential of vFFR to guide the management of unselected patients undergoing ICA. The hypothesis was that it changes management in >10% of cases.

METHODS

vFFR was computed using the Sheffield VIRTUheart system, at five hospitals in the North of England, on 'all-comers' undergoing ICA for non-ST-elevation myocardial infarction acute coronary syndrome (ACS) and chronic coronary syndrome (CCS). The cardiologists' management plan (optimal medical therapy, percutaneous coronary intervention (PCI), coronary artery bypass surgery or 'more information required') and confidence level were recorded after ICA, and again after vFFR disclosure.

RESULTS

517 patients were screened; 320 were recruited: 208 with ACS and 112 with CCS. The median vFFR was 0.82 (0.70-0.91). vFFR disclosure did not change the mean number of significantly stenosed vessels per patient (1.16 (±0.96) visually and 1.18 (±0.92) with vFFR (p=0.79)). A change in intended management following vFFR disclosure occurred in 22% of all patients; in the ACS cohort, there was a 62% increase in the number planned for medical management, and in the CCS cohort, there was a 31% increase in the number planned for PCI. In all patients, vFFR disclosure increased physician confidence from 8 of 10 (7.33-9) to 9 of 10 (8-10) (p<0.001).

CONCLUSION

The addition of vFFR to ICA changed intended management strategy in 22% of patients, provided a detailed and specific 'all-in-one' anatomical and physiological assessment of coronary artery disease, and was accompanied by augmentation of the operator's confidence in the treatment strategy.

Efficacy of Diagnostic Testing of Suspected Coronary Artery Disease: A Contemporary Review

BACKGROUND

Coronary artery disease (CAD) is a highly prevalent condition which can lead to myocardial ischemia as well as acute coronary syndrome. Early diagnosis of CAD can improve patient outcomes through guiding risk factor modification and treatment modalities.

SUMMARY

Testing for CAD comes with increased cost and risk; therefore, physicians must determine which patients require testing, and what testing modality will offer the most useful data to diagnose patients with CAD. Patients should have an initial risk stratification for pretest probability of CAD based on symptoms and available clinical data. Patients with a pretest probability less than 5% should receive no further testing, while patients with a high pretest probability should be considered for direct invasive coronary angiography. In patients with a pretest probability between 5 and 15%, coronary artery calcium score and or exercise electrocardiogram can be obtained to further risk stratify patients to low-risk versus intermediate-high-risk. Intermediate-high-risk patients should be tested with coronary computed tomography angiography (preferred) versus positron emission tomography or single photon emission computed tomography based on their individual patient characteristics and institutional availability.

KEY MESSAGES

This comprehensive review aimed to describe the available CAD testing modalities, detail their risks and benefits, and propose when each should be considered in the evaluation of a patient with suspected CAD.

Clinical Validation of a Deep Learning Algorithm for Automated Coronary Artery Disease Detection and Classification Using a Heterogeneous Multivendor Coronary Computed Tomography Angiography Data Set

PURPOSE

We sought to clinically validate a fully automated deep learning (DL) algorithm for coronary artery disease (CAD) detection and classification in a heterogeneous multivendor cardiac computed tomography angiography data set.

MATERIALS AND METHODS

In this single-centre retrospective study, we included patients who underwent cardiac computed tomography angiography scans between 2010 and 2020 with scanners from 4 vendors (Siemens Healthineers, Philips, General Electrics, and Canon). Coronary Artery Disease-Reporting and Data System (CAD-RADS) classification was performed by a DL algorithm and by an expert reader (reader 1, R1), the gold standard. Variability analysis was performed with a second reader (reader 2, R2) and the radiologic reports on a subset of cases. Statistical analysis was performed stratifying patients according to the presence of CAD (CAD-RADS >0) and obstructive CAD (CAD-RADS ≥3).

RESULTS

Two hundred ninety-six patients (average age: 53.66 ± 13.65, 169 males) were enrolled. For the detection of CAD only, the DL algorithm showed sensitivity, specificity, accuracy, and area under the curve of 95.3%, 79.7%, 87.5%, and 87.5%, respectively. For the detection of obstructive CAD, the DL algorithm showed sensitivity, specificity, accuracy, and area under the curve of 89.4%, 92.8%, 92.2%, and 91.1%, respectively. The variability analysis for the detection of obstructive CAD showed an accuracy of 92.5% comparing the DL algorithm with R1, and 96.2% comparing R1 with R2 and radiology reports. The time of analysis was lower using the DL algorithm compared with R1 (P < 0.001).

CONCLUSIONS

The DL algorithm demonstrated robust performance and excellent agreement with the expert readers' analysis for the evaluation of CAD, which also corresponded with significantly reduced image analysis time.

Regional variability of cardiovascular magnetic resonance access and utilization in the United States

BACKGROUND

Clinical guidelines and scientific data increasingly support the appropriate use of cardiovascular magnetic resonance (CMR) . The extent of CMR adoption across the United States (US) remains unclear. This observational analysis aims to capture CMR practice patterns in the US.

METHODS

Commissioned reports from the Society for Cardiovascular Magnetic Resonance (SCMR), pre-existing survey data from CMR centers, and socioeconomic and coronary heart disease data from the Centers for Disease Control and Prevention were used. The location of imaging centers performing CMR was based on 2018 Medicare claims. Secondary analysis was performed on center-specific survey data from 2017-2019, which were collected by members of the SCMR US Advocacy Subcommittee for quality improvement purposes. The correlation between the number of imaging centers billing for CMR services per million persons, socioeconomic determinants, and coronary heart disease epidemiology was determined.

RESULTS

A total of 591 imaging centers billed the Center for Medicare & Medicaid Services for CMR services in 2018 and 112 (of 155) unique CMR centers responded to the survey. In 2018, CMR services were available in almost all 50 states. Minnesota was the state with the highest number of CMR centers per million Medicare beneficiaries (52.6 centers per million), and Maine had the lowest (4.4 per million). The total density of CMR centers was 16 per million for US Medicare beneficiaries. Sixty-eight percent (83 of 112) of survey responders were cardiologists, and 28% (31/112) were radiologists. In 72% (71/112) of centers, academic health care systems performed 81%-100% of CMR exams. The number of high-volume centers (>500 scans per year) increased by seven between 2017 and 2019. In 2019, 53% (59/112) of centers were considered high-volume centers and had an average of 19 years of experience. Centers performing <50 scans had on average 3.5 years of experience. Approximate patient wait time for a CMR exam was 2 weeks to 1 month.

CONCLUSION

Despite increasing volume and availability in almost all 50 states, CMR access remains geographically variable. Advocacy efforts to improve access and innovations that reduce imaging time and exam complexity have the potential to increase the adoption of CMR technology.

Diagnosis and treatment of ischemia-producing coronary stenoses improves 5-year survival of patients undergoing major vascular surgery

OBJECTIVE

Patients undergoing vascular surgery procedures have poor long-term survival due to coexisting coronary artery disease (CAD), which is often asymptomatic, undiagnosed, and undertreated. We sought to determine whether preoperative diagnosis of asymptomatic (silent) coronary ischemia using coronary computed tomography (CT)-derived fractional flow reserve (FFRCT) together with postoperative ischemia-targeted coronary revascularization can reduce adverse cardiac events and improve long-term survival following major vascular surgery METHODS: In this observational cohort study of 522 patients with no known CAD undergoing elective carotid, peripheral, or aneurysm surgery we compared two groups of patients. Group I included 288 patients enrolled in a prospective Institutional Review Board-approved study of preoperative coronary CT angiography (CTA) and FFRCT testing to detect silent coronary ischemia with selective postoperative coronary revascularization in addition to best medical therapy (BMT) (FFRCT guided), and Group II included 234 matched controls with standard preoperative cardiac evaluation and postoperative BMT alone with no elective coronary revascularization (Usual Care). In the FFRCT group, lesion-specific coronary ischemia was defined as FFRCT ≤0.80 distal to a coronary stenosis, with severe ischemia defined as FFRCT ≤0.75. Results were available for patient management decisions. Endpoints included all-cause death, cardiovascular death, myocardial infarction (MI), and major adverse cardiovascular events (MACE [death, MI, or stroke]) during 5-year follow-up.

RESULTS

The two groups were similar in age, gender, and comorbidities. In FFRCT, 65% of patients had asymptomatic lesion-specific coronary ischemia, with severe ischemia in 52%, multivessel ischemia in 36% and left main ischemia in 8%. The status of coronary ischemia was unknown in Usual Care. Vascular surgery was performed as planned in both cohorts with no difference in 30-day mortality. In FFRCT, elective ischemia-targeted coronary revascularization was performed in 103 patients 1 to 3 months following surgery. Usual Care had no elective postoperative coronary revascularizations. At 5 years, compared with Usual Care, FFRCT guided had fewer all-cause deaths (16% vs 36%; hazard ratio [HR], 0.37; 95% confidence interval [CI], 0.22-0.60; P < .001), fewer cardiovascular deaths (4% vs 21%; HR, 0.11; 95% CI, 0.04-0.33; P < .001), fewer MIs (4% vs 24%; HR, 0.13; 95% CI, 0.05-0.33; P < .001), and fewer MACE (20% vs 47%; HR, 0.36; 95% CI, 0.23-0.56; P < .001). Five-year survival was 84% in FFRCT compared with 64% in Usual Care (P < .001).

CONCLUSIONS

Diagnosis of silent coronary ischemia with ischemia-targeted coronary revascularization in addition to BMT following major vascular surgery was associated with fewer adverse cardiovascular events and improved 5-year survival compared with patients treated with BMT alone as per current guidelines.