Myocardial Infarction in the ISCHEMIA Trial: Impact of Different Definitions on Incidence, Prognosis, and Treatment Comparisons

Mortality After Procedural or Spontaneous Myocardial Infarction

BACKGROUND

It remains unclear whether procedural myocardial infarction (pMI) and spontaneous myocardial infarction (spMI) have a similar impact on prognosis.

OBJECTIVES

The aim of this study was to assess mortality after pMI and spMI.

METHODS

Patients with chronic coronary syndrome (CCS) and baseline troponin ≤1× the upper reference level (URL) or with acute spMI who underwent percutaneous coronary intervention (PCI) were included. PMI was defined as post-PCI troponin increase >1× URL in patients with CCS. SpMI comprised any acute coronary syndrome with elevated troponin. The 1-year risk of all-cause death was assessed after pMI and spMI across 3 strata of troponin elevation (>1-5×, >5-35×, and >35× URL), with CCS patients having post-PCI troponin ≤1× URL as a reference group. Conventional troponin I was measured using the Architect methodology (Abbott).

RESULTS

Among 10,707 patients undergoing PCI from 2012 to 2020, 8,515 patients presented with CCS and 2,192 with spMI. Among CCS patients, 913 (10.7%) had pMI. Troponin peaks >1-5×, >5-35×, and >35× URL were observed in 53%, 41%, and 6% of patients with pMI, and in 24%, 38%, and 37% of patients with spMI, respectively. Mortality at 1 year was higher after pMI (7.7%; adjusted HR: 4.40; 95% CI: 1.59-12.2), and spMI (8.5%; adjusted HR: 7.57; 95% CI: 5.44-10.5) with troponin peak >35× URL compared with no-MI (1.4%). Mortality was also increased after spMI with troponin peak >1-5× or >5-35× URL.

CONCLUSIONS

Mortality at 1 year was significantly increased after pMI and spMI with troponin peak >35× URL, whereas for troponin levels ≤35× only spMI had a relevant impact on mortality.

PET Myocardial Perfusion Imaging: Trends, Challenges, and Opportunities

Various non-invasive images are used in clinical practice for the diagnosis and prognostication of chronic coronary syndromes. Notably, quantitative myocardial perfusion imaging (MPI) through positron emission tomography (PET) has seen significant technical advancements and a substantial increase in its use over the past two decades. This progress has generated an unprecedented wealth of clinical information, which, when properly applied, can diagnose and fine-tune the management of patients with different types of ischemic syndromes. This state-of-art review focuses on quantitative PET MPI, its integration into clinical practice, and how it holds up at the eyes of modern cardiac imaging and revascularization clinical trials, along with future perspectives.

Periprocedural myocardial infarction and injury

Periprocedural myocardial infarction (PMI) and injury, pertinent to both cardiac and non-cardiac procedures, have gained increasing recognition in clinical practice. Over time, diverse definitions for diagnosing PMI have been developed and validated among patient populations undergoing coronary revascularization. However, this variety in definitions presents considerable challenges in clinical settings and complicates both the design and interpretation of clinical trials. The necessity to accurately diagnose PMI has spurred significant interest in establishing universally accepted and prognostically meaningful thresholds for cardiac biomarkers elevation and supportive ancillary criteria. In fact, elevations in cardiac biomarkers in line with the 4th Universal Definition of Myocardial Infarction, have been extensively confirmed to be associated with increased mortality and cardiovascular events. In the context of non-coronary cardiac procedures, such as Transcatheter Aortic Valve Implantation, there is a growing acknowledgment of both the high incidence rates and the adverse impact of PMI on patient outcomes. Similarly, emerging research underscores the significance of PMI and injury in non-cardiac surgery, highlighting the urgent need for effective prevention and risk management strategies in this domain.

Percutaneous Coronary Intervention versus Optimal Medical Therapy in Patients with Chronic Total Occlusion: A Meta-Analysis

Background/Objectives: Chronic total occlusion (CTO) is a prevalent finding in patients with coronary artery disease and is associated with increased mortality. Prior reports on the efficacy of percutaneous coronary intervention (PCI) compared to optimal medical therapy (OMT) were controversial. Following the emergence of recently published new evidence, a meta-analysis is warranted. The current meta-analysis assessed the effects of PCI compared to OMT in the treatment of CTO. Methods: A structured literature search was performed. Randomized controlled trials (RCTs) and non-randomized controlled studies of interventions were eligible. The primary outcome was an accumulated composite of cardiac mortality, myocardial infarction and target vessel/lesion revascularization events. Results: Thirty-two studies reporting on 11260 patients were included. Of these, 5712 (50.7%) were assigned to the PCI and 5548 (49.3%) were allocated to the OMT group. The primary outcome occurred in 14.6% of the PCI and 20.1% of the OMT group (12 trials, OR 0.66, 95% CI 0.50 to 0.88, p = 0.005, I2 = 67%). Subgrouping demonstrated a consistent reduction in the primary outcome for the PCI group in RCTs (six trials, OR 0.58, 95% CI 0.33 to 0.99, p = 0.05). The primary outcome reduction was irrespective of the study design, and it was replicable in sensitivity and subgroup analyses. Advantages in other outcomes were rather related to statistical pooling effects and dominated by observational data. Conclusions: CTO-PCI was associated with improved patient-oriented primary outcome compared to OMT in a study-level meta-analysis. This composite outcome effect was mainly driven by target vessel treatment, but a significant reduction in mortality and myocardial infarction was observed, irrespectively. These findings have hypothesis-generating implications. Future RCTs with adequate statistical power are eagerly awaited.

Periprocedural myocardial infarction after percutaneous coronary intervention and long-term mortality: a meta-analysis

BACKGROUND AND AIMS

Conflicting data are available regarding the association between periprocedural myocardial infarction (PMI) and mortality following percutaneous coronary intervention. The purpose of this study was to evaluate the incidence and prognostic implication of PMI according to the Universal Definition of Myocardial Infarction (UDMI), the Academic Research Consortium (ARC)-2 definition, and the Society for Cardiovascular Angiography and Interventions (SCAI) definition.

METHODS

Studies reporting adjusted effect estimates were systematically searched. The primary outcome was all-cause death, while cardiac death was included as a secondary outcome. Studies defining PMI according to biomarker elevation without further evidence of myocardial ischaemia ('ancillary criteria') were included and reported as 'definition-like'. Data were pooled in a random-effect model.

RESULTS

A total of 19 studies and 109 568 patients were included. The incidence of PMI was progressively lower across the UDMI, ARC-2, and SCAI definitions. All PMI definitions were independently associated with all-cause mortality [UDMI: hazard ratio (HR) 1.61, 95% confidence interval (CI) 1.32-1.97; I2 34%; ARC-2: HR 2.07, 95% CI 1.40-3.08, I2 0%; SCAI: HR 3.24, 95% CI 2.36-4.44, I2 78%]. Including ancillary criteria in the PMI definitions were associated with an increased prognostic performance in the UDMI but not in the SCAI definition. Data were consistent after evaluation of major sources of heterogeneity.

CONCLUSIONS

All currently available international definitions of PMI are associated with an increased risk of all-cause death after percutaneous coronary intervention. The magnitude of this latter association varies according to the sensitivity and prognostic relevance of each definition.

Outcomes by sex in the International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) trial

BACKGROUND

In the International Study of Comparative Health Effectiveness With Medical and Invasive Approaches (ISCHEMIA) trial, among participants with stable coronary artery disease, the risk of cardiac events was similar between an invasive (INV) strategy of angiography and coronary revascularisation and a conservative (CON) strategy of initial medical therapy alone. Outcomes according to participant sex were not reported.

AIMS

We aimed to analyse the outcomes of ISCHEMIA by participant sex.

METHODS

We evaluated 1) the association between participant sex and the likelihood of undergoing revascularisation for participants randomised to the INV arm; 2) the risk of the ISCHEMIA primary composite outcome (cardiovascular death, any myocardial infarction [MI] or rehospitalisation for unstable angina, heart failure or resuscitated cardiac arrest) by participant sex; and 3) the contribution of the individual primary outcome components to the composite outcome by participant sex.

RESULTS

Of 5,179 randomised participants, 1,168 (22.6%) were women. Female sex was independently associated with a lower likelihood of revascularisation when assigned to the INV arm (adjusted odds ratio 0.75, 95% confidence interval [CI]: 0.57-0.99; p=0.04). The INV versus CON effect on the primary composite outcome was similar between sexes (women: hazard ratio [HR] 0.96, 95% CI: 0.70-1.33; men: HR 0.90, 95% CI: 0.76-1.07; pinteraction=0.71). The contribution of the individual components to the composite outcome was similar between sexes except for procedural MI, which was significantly lower in women (9/151 [5.9%]) than men (67/519 [12.9%]; p=0.01).

CONCLUSIONS

In ISCHEMIA, women assigned to the INV arm were less likely to undergo revascularisation than men. The effect of an INV versus CON strategy was consistent by sex, but women had a significantly lower contribution of procedural MI to the primary outcome.

A Narrative Review of Revascularization in Chronic Coronary Syndrome/Disease: Concepts and Misconceptions

Ischemic heart disease represents a significant global burden of morbidity and mortality. While revascularization strategies are well defined in acute settings, there are uncertainties regarding chronic coronary artery disease treatment. Recent trials have raised doubts about the necessity of revascularization for "stable", chronic coronary syndromes or disease, leading to a shift towards a more conservative approach. However, the issue remains far from settled. In this narrative review, we offer a summary of the most pertinent evidence regarding revascularization for chronic coronary disease, while reflecting on less-often-discussed details of major clinical trials. The cumulative evidence available indicates that there can be a prognostic benefit from revascularization in chronic coronary syndrome patients, provided there is significant ischemia, as demonstrated by either imaging or coronary physiology. Trials that have effectively met this criterion consistently demonstrate a reduction in rates of spontaneous myocardial infarction, which holds both prognostic and clinical significance. The prognostic benefit of revascularization in patients with heart failure with reduced ejection fraction remains especially problematic, with a single contemporary trial favouring surgical revascularization. The very recent publication of a trial focused on revascularizing non-flow-limiting "vulnerable" plaques adds further complexity to the field. The ongoing debates surrounding revascularization in chronic coronary syndromes emphasize the importance of personalized strategies. Revascularization, added to the foundational pillar of medical therapy, should be considered, taking into account symptoms, patient preferences, coronary anatomy and physiology, ischemia tests and intra-coronary imaging.

Prognostic value of a novel artificial intelligence-based coronary computed tomography angiography-derived ischaemia algorithm for patients with suspected coronary artery disease

AIMS

Coronary computed tomography angiography (CTA) imaging is used to diagnose patients with suspected coronary artery disease (CAD). A novel artificial intelligence-guided quantitative computed tomography ischaemia algorithm (AI-QCTischaemia) aims to identify myocardial ischaemia directly from CTA images and may be helpful to improve risk stratification. The aims were to investigate (i) the prognostic value of AI-QCTischaemia amongst symptomatic patients with suspected CAD entering diagnostic imaging with coronary CTA and (ii) the prognostic value of AI-QCTischaemia separately amongst patients with no/non-obstructive CAD (≤50% visual diameter stenosis) and obstructive CAD (>50% visual diameter stenosis).

METHODS AND RESULTS

For this cohort study, AI-QCTischaemia was calculated by blinded analysts amongst patients with suspected CAD undergoing coronary CTA. The primary endpoint was the composite of death, myocardial infarction (MI), or unstable angina pectoris (uAP) (median follow-up 6.9 years). A total of 1880/2271 (83%) patients had conclusive AI-QCTischaemia result. Patients with an abnormal AI-QCTischaemia result (n = 509/1880) vs. patients with a normal AI-QCTischaemia result (n = 1371/1880) had significantly higher crude and adjusted rates of the primary endpoint [adjusted hazard ratio (HRadj) 1.96, 95% confidence interval (CI) 1.46-2.63, P < 0.001; covariates: age/sex/hypertension/diabetes/smoking/typical angina]. An abnormal AI-QCTischaemia result was associated with significantly higher crude and adjusted rates of the primary endpoint amongst patients with no/non-obstructive CAD (n = 1373/1847) (HRadj 1.81, 95% CI 1.09-3.00, P = 0.022), but not amongst those with obstructive CAD (n = 474/1847) (HRadj 1.26, 95% CI 0.75-2.12, P = 0.386) (P-interaction = 0.032).

CONCLUSION

Amongst patients with suspected CAD, an abnormal AI-QCTischaemia result was associated with a two-fold increased adjusted rate of long-term death, MI, or uAP. AI-QCTischaemia may be useful to improve risk stratification, especially amongst patients with no/non-obstructive CAD on coronary CTA.

Sex Differences in Revascularization, Treatment Goals, and Outcomes of Patients With Chronic Coronary Disease: Insights From the ISCHEMIA Trial

BACKGROUND

Women with chronic coronary disease are generally older than men and have more comorbidities but less atherosclerosis. We explored sex differences in revascularization, guideline-directed medical therapy, and outcomes among patients with chronic coronary disease with ischemia on stress testing, with and without invasive management.

METHODS AND RESULTS

The ISCHEMIA (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches) trial randomized patients with moderate or severe ischemia to invasive management with angiography, revascularization, and guideline-directed medical therapy, or initial conservative management with guideline-directed medical therapy alone. We evaluated the primary outcome (cardiovascular death, myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest) and other end points, by sex, in 1168 (22.6%) women and 4011 (77.4%) men. Invasive group catheterization rates were similar, with less revascularization among women (73.4% of invasive-assigned women revascularized versus 81.2% of invasive-assigned men; P<0.001). Women had less coronary artery disease: multivessel in 60.0% of invasive-assigned women and 74.8% of invasive-assigned men, and no ≥50% stenosis in 12.3% versus 4.5% (P<0.001). In the conservative group, 4-year catheterization rates were 26.3% of women versus 25.6% of men (P=0.72). Guideline-directed medical therapy use was lower among women with fewer risk factor goals attained. There were no sex differences in the primary outcome (adjusted hazard ratio [HR] for women versus men, 0.93 [95% CI, 0.77-1.13]; P=0.47) or the major secondary outcome of cardiovascular death/myocardial infarction (adjusted HR, 0.93 [95% CI, 0.76-1.14]; P=0.49), with no significant sex-by-treatment-group interactions.

CONCLUSIONS

Women had less extensive coronary artery disease and, therefore, lower revascularization rates in the invasive group. Despite lower risk factor goal attainment, women with chronic coronary disease experienced similar risk-adjusted outcomes to men in the ISCHEMIA trial.

REGISTRATION

URL: http://wwwclinicaltrials.gov. Unique identifier: NCT01471522.

Optimal medical therapy vs revascularization in chronic coronary syndromes: Does ISCHEMIA move the needle toward or away from revascularization??

The optimal management of chronic coronary syndrome (CCS) patients has been a source of debate for several decades. Herein, we describe the evidence base comprising several landmark clinical trials including the most recent ISCHEMIA Trial, which, in aggregate, does not demonstrate a conclusive, incremental benefit of revascularization combined with optimal medical therapy (OMT) versus OMT alone in reducing prognostically-important clinical outcomes during long-term follow-up. For CCS patients with symptoms or quality of life not deemed refractory or unacceptable on medical therapy, a conservative approach to the judicious and selective use of revascularization plus OMT remains a justifiable evidence-based management strategy.

Depression and coronary heart disease: mechanisms, interventions, and treatments

Coronary heart disease (CHD), a cardiovascular condition that poses a significant threat to human health and life, has imposed a substantial economic burden on the world. However, in contrast to conventional risk factors, depression emerges as a novel and independent risk factor for CHD. This condition impacts the onset and progression of CHD and elevates the risk of adverse cardiovascular prognostic events in those already affected by CHD. As a result, depression has garnered increasing global attention. Despite this growing awareness, the specific mechanisms through which depression contributes to the development of CHD remain unclear. Existing research suggests that depression primarily influences the inflammatory response, Hypothalamic-pituitary-adrenocortical axis (HPA) and Autonomic Nervous System (ANS) dysfunction, platelet activation, endothelial dysfunction, lipid metabolism disorders, and genetics, all of which play pivotal roles in CHD development. Furthermore, the effectiveness and safety of antidepressant treatment in CHD patients with comorbid depression and its potential impact on the prognosis of CHD patients have become subjects of controversy. Further investigation is warranted to address these unresolved questions.

Outcomes According to Coronary Revascularization Modality in the ISCHEMIA Trial

BACKGROUND

In the ISCHEMIA (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches) trial, the risk of ischemic events was similar in patients with stable coronary artery disease treated with an invasive (INV) strategy of angiography and percutaneous coronary intervention (PCI) or surgical (coronary artery bypass grafting [CABG]) coronary revascularization and a conservative (CON) strategy of initial medical therapy.

OBJECTIVES

The authors analyzed separately the outcomes of INV patients treated with PCI or CABG.

METHODS

Patients without preceding primary outcome events were categorized as INV-PCI or INV-CABG from the time of revascularization. The ISCHEMIA primary outcome (composite of cardiovascular death, protocol-defined myocardial infarction or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest) was used.

RESULTS

Among INV-CABG patients, primary outcome events occurred in 84 of 512 (16.4%) at a median follow-up of 2.85 years; 48 events (57.1%) occurred within 30 days after CABG, including 40 procedural MIs. Among INV-PCI patients, primary outcome events occurred in 147 of 1,500 (9.8%) at median follow-up of 2.94 years; 31 of which (21.1%) occurred within 30 days after PCI, including 24 procedural MIs. In comparison, 352 of 2,591 CON patients (13.6%) had primary outcome events at a median follow-up of 3.2 years, 22 of which (6.3%) occurred within 30 days of randomization. The adjusted primary outcome risks were higher after both CABG and PCI within 30 days (HR: 16.25 [95% CI: 11.44-23.07] and HR: 2.99 [95% CI: 1.97-4.53]) and lower thereafter (0.63 [95% CI: 0.44-0.89] and 0.66 [95% CI: 0.53-0.82]).

CONCLUSIONS

In ISCHEMIA, early revascularization by PCI and CABG was associated with higher early risks and lower long-term risks of cardiovascular events compared with CON. The early risk was greatest after CABG, owing to protocol-defined procedural MIs.

What About All the Recent "Negative" FFR Trials?

During the past 30 years, fractional flow reserve (FFR) has moved from animal models to class IA recommendations in guidelines. However, the FLOWER-MI, RIPCORD-2, FUTURE, and FAME 3 trials in 2021 were "negative"-has FFR exceeded its expiration date? We critically examine these randomized trials in order to draw insights not just about FFR but also about study design and interpretation. Are all randomized trials created equal? No, rather we must focus on discordant decisions between angiography and FFR and highlight clinical endpoints that can be improved by percutaneous coronary intervention instead of medical therapy.

Impact of biomarker type on periprocedural myocardial infarction in patients undergoing elective PCI

BACKGROUND

Periprocedural myocardial infarction (MI) according to the Society for Cardiovascular Angiography and Interventions (SCAI) criteria has prognostic relevance among patients undergoing percutaneous coronary intervention (PCI). However, it is unclear whether the type of cardiac biomarker used for the diagnosis of periprocedural MI plays a role in terms of event frequency and outcomes.

OBJECTIVES

To compare the characteristics of SCAI periprocedural MI based on creatine kinase-myocardial band fraction (CK-MB) vs. high-sensitivity cardiac troponin (hs-cTn) in patients undergoing elective PCI.

METHODS AND RESULTS

Between 2017 and 2021, periprocedural MI was assessed in a prospective study. The primary clinical outcome of interest was all-cause death at 1-year follow-up. A total of 1010 patients undergoing elective PCI were included. SCAI periprocedural MI based on CK-MB vs. hs-cTnI occurred in 1.8 and 13.5% of patients, respectively. hs-cTnI periprocedural MI in the absence of concomitant CK-MB criteria was associated with lower rates of ancillary criteria, including angiographic, ECG, and cardiac imaging criteria. At 1-year follow-up, periprocedural MI defined by CK-MB (adjusted hazard ratio, HR, 4.27, 95% confidence intervals, CI, 1.23-14.8; P = 0.022) but not hs-cTnI (adjusted HR 2.04, 95% CI 0.94-4.45; P = 0.072) was associated with a higher risk of all-cause death. Hs-cTnI periprocedural MI was not predictive of death unless accompanied by CK-MB criteria (adjusted HR 4.64, 95% CI 1.32-16.31; P = 0.017).

CONCLUSION

In the setting of elective PCI, using hs-cTn instead of CK-MB resulted in a substantial increase in SCAI periprocedural MI events, which were not prognostically relevant in the absence of concurrent CK-MB elevations.

Coronary Atherosclerosis Phenotypes in Focal and Diffuse Disease

BACKGROUND

The interplay between coronary hemodynamics and plaque characteristics remains poorly understood.

OBJECTIVES

The aim of this study was to compare atherosclerotic plaque phenotypes between focal and diffuse coronary artery disease (CAD) defined by coronary hemodynamics.

METHODS

This multicenter, prospective, single-arm study was conducted in 5 countries. Patients with functionally significant lesions based on an invasive fractional flow reserve ≤0.80 were included. Plaque analysis was performed by using coronary computed tomography angiography and optical coherence tomography. CAD patterns were assessed using motorized fractional flow reserve pullbacks and quantified by pullback pressure gradient (PPG). Focal and diffuse CAD was defined according to the median PPG value.

RESULTS

A total of 117 patients (120 vessels) were included. The median PPG was 0.66 (IQR: 0.54-0.75). According to coronary computed tomography angiography analysis, plaque burden was higher in patients with focal CAD (87% ± 8% focal vs 82% ± 10% diffuse; P = 0.003). Calcifications were significantly more prevalent in patients with diffuse CAD (Agatston score per vessel: 51 [IQR: 11-204] focal vs 158 [IQR: 52-341] diffuse; P = 0.024). According to optical coherence tomography analysis, patients with focal CAD had a significantly higher prevalence of circumferential lipid-rich plaque (37% focal vs 4% diffuse; P = 0.001) and thin-cap fibroatheroma (TCFA) (47% focal vs 10% diffuse; P = 0.002). Focal disease defined by PPG predicted the presence of TCFA with an area under the curve of 0.73 (95% CI: 0.58-0.87).

CONCLUSIONS

Atherosclerotic plaque phenotypes associate with intracoronary hemodynamics. Focal CAD had a higher plaque burden and was predominantly lipid-rich with a high prevalence of TCFA, whereas calcifications were more prevalent in diffuse CAD. (Precise Percutaneous Coronary Intervention Plan [P3]; NCT03782688).

Dealing With Nonproportional Hazards in Coronary Revascularisation Studies

The Cox proportional hazards model is one of the most popular statistical tools to model time to event outcomes without the need for specifying the hazards or survival time distributions. The Cox model requires that the ratio of the hazards of the occurrence of the outcome for any 2 individuals remains constant during the entire follow-up. Studies comparing coronary revascularisation strategies, however, might be prone to violations of proportionality by the crossing of the hazard functions over time. Early increases in the risk of cardiovascular outcomes are commonly observed when comparing coronary artery bypass grafting vs percutaneous coronary intervention, whereas decreased risk might be observed later during the follow-up. The same is valid for comparisons between invasive vs conservative coronary revascularisation strategies. In these situations, the statistical power of the Cox model is reduced, and hazard ratios might not be an informative summary measure of treatment effect. In this article, we discuss methods to identify and account for nonproportionality. We illustrate the use of these methods in a case study based on reconstructed data from a coronary revascularisation clinical trial. And finally, we review the cardiovascular literature to estimate how the proportionality assumption has been reported in coronary revascularisation studies recently.

The Evolving Paradigm of Revascularization in Ischemic Cardiomyopathy: from Recovery of Systolic Function to Protection Against Future Ischemic Events

PURPOSE OF REVIEW

We aim to reevaluate how the assessment of myocardial viability can guide optimal treatment strategies for patients with ischemic cardiomyopathy (ICM) based on a more contemporary understanding of the mechanism of benefit of revascularization.

RECENT FINDINGS

The assessment of viability in left ventricular (LV) segments with diminished contraction has been proposed as key to predict the benefit of revascularization and, therefore, as a requisite for the selection of patients to undergo this form of treatment. However, data from prospective trials have diverged from earlier retrospective studies. Traditional binary viability assessment may oversimplify ICM's complexity and the nuances of revascularization benefits. A conceptual shift from the traditional paradigm centered on the assessment of viability as a dichotomous variable to a more comprehensive approach encompassing a thorough understanding of ICM's complex pathophysiology and the salutary effect of revascularization in the prevention of myocardial infarction and ventricular arrhythmias is required.

Why percutaneous revascularisation might not reduce the risk of myocardial infarction and mortality in patients with stable CAD?

Percutaneous coronary intervention (PCI) is widely adopted to treat chronic coronary artery disease. Numerous randomised trials have been conducted to test whether PCI may provide any prognostic advantage over oral medical therapy (OMT) alone, without definitive results. This has maintained the paradigm of OMT as the first-line standard of care for patients, reserving PCI for symptom control. In this review, we discuss the current evidence in favour and against PCI in stable coronary syndromes and highlight the pitfalls of the available studies. We offer a critical appraisal of the possible reasons why the existing data does not provide evidence supporting the role of PCI in improving clinical outcomes in patients with stable coronary syndromes.

Atherosclerotic plaque vulnerability quantification system for clinical and biological interpretability

Acute myocardial infarction dominates coronary artery disease mortality. Identifying bio-signatures for plaque destabilization and rupture is important for preventing the transition from coronary stability to instability and the occurrence of thrombosis events. This computational systems biology study enrolled 2,235 samples from 22 independent bulks cohorts and 14 samples from two single-cell cohorts. A machine-learning integrative program containing nine learners was developed to generate a warning classifier linked to atherosclerotic plaque vulnerability signature (APVS). The classifier displays the reliable performance and robustness for distinguishing ST-elevation myocardial infarction from chronic coronary syndrome at presentation, and revealed higher accuracy to 33 pathogenic biomarkers. We also developed an APVS-based quantification system (APVSLevel) for comprehensively quantifying atherosclerotic plaque vulnerability, empowering early-warning capabilities, and accurate assessment of atherosclerosis severity. It unraveled the multidimensional dysregulated mechanisms at high resolution. This study provides a potential tool for macro-level differential diagnosis and evaluation of subtle genetic pathological changes in atherosclerosis.

Clinical outcomes associated with type II myocardial infarction caused by bleeding

BACKGROUND

Type ll myocardial infarction (T2MI) is caused by a mismatch between myocardial oxygen supply and demand. One subset of individuals is T2MI caused by acute hemorrhage. Traditional MI treatments including antiplatelets, anticoagulants, and revascularization can worsen bleeding. We aim to report outcomes of T2MI patients due to bleeding, stratified by treatment approach.

METHODS

The MGB Research Patient Data Registry followed by manual physician adjudication was used to identify individuals with T2MI caused by bleeding between 2009 and 2022. We defined 3 treatment groups: (1) invasively managed, (2) pharmacologic, and (3) conservatively managed Clinical parameters and outcomes for 30-day, mortality, rebleeding, and readmission were abstracted compared between the treatment groups.

RESULTS

We identified 5,712 individuals coded with acute bleeding, of which 1,017 were coded with T2MI during their admission. After manual physician adjudication, 73 individuals met the criteria for T2MI caused by bleeding. 18 patients were managed invasively, 39 received pharmacologic therapy alone, and 16 were managed conservatively. The invasively managed group experienced lower mortality (P = .021) yet higher readmission (P = .045) than the conservatively managed group. The pharmacologic group also experienced lower mortality (P= .017) yet higher readmission (P = .005) than the conservatively managed group.

CONCLUSION

Individuals with T2MI associated with acute hemorrhage are a high-risk population. Patients treated with standard procedures experienced higher readmission but lower mortality than conservatively managed patients. These results raise the possibility of testing ischemia-reduction approaches for such high-risk populations. Future clinical trials are required to validate treatment strategies for T2MI caused by bleeding.

2023 AHA/ACC/ACCP/ASPC/NLA/PCNA Guideline for the Management of Patients With Chronic Coronary Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2023 AHA/ACC/ACCP/ASPC/NLA/PCNA Guideline for the Management of Patients With Chronic Coronary Disease" provides an update to and consolidates new evidence since the "2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease" and the corresponding "2014 ACC/AHA/AATS/PCNA/SCAI/STS Focused Update of the Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease."

METHODS

A comprehensive literature search was conducted from September 2021 to May 2022. Clinical studies, systematic reviews and meta-analyses, and other evidence conducted on human participants were identified that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

This guideline provides an evidenced-based and patient-centered approach to management of patients with chronic coronary disease, considering social determinants of health and incorporating the principles of shared decision-making and team-based care. Relevant topics include general approaches to treatment decisions, guideline-directed management and therapy to reduce symptoms and future cardiovascular events, decision-making pertaining to revascularization in patients with chronic coronary disease, recommendations for management in special populations, patient follow-up and monitoring, evidence gaps, and areas in need of future research. Where applicable, and based on availability of cost-effectiveness data, cost-value recommendations are also provided for clinicians. Many recommendations from previously published guidelines have been updated with new evidence, and new recommendations have been created when supported by published data.

2023 AHA/ACC/ACCP/ASPC/NLA/PCNA Guideline for the Management of Patients With Chronic Coronary Disease: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2023 AHA/ACC/ACCP/ASPC/NLA/PCNA Guideline for the Management of Patients With Chronic Coronary Disease" provides an update to and consolidates new evidence since the "2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease" and the corresponding "2014 ACC/AHA/AATS/PCNA/SCAI/STS Focused Update of the Guideline for the Diagnosis and Management of Patients With Stable Ischemic Heart Disease."

METHODS

A comprehensive literature search was conducted from September 2021 to May 2022. Clinical studies, systematic reviews and meta-analyses, and other evidence conducted on human participants were identified that were published in English from MEDLINE (through PubMed), EMBASE, the Cochrane Library, Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline.

STRUCTURE

This guideline provides an evidenced-based and patient-centered approach to management of patients with chronic coronary disease, considering social determinants of health and incorporating the principles of shared decision-making and team-based care. Relevant topics include general approaches to treatment decisions, guideline-directed management and therapy to reduce symptoms and future cardiovascular events, decision-making pertaining to revascularization in patients with chronic coronary disease, recommendations for management in special populations, patient follow-up and monitoring, evidence gaps, and areas in need of future research. Where applicable, and based on availability of cost-effectiveness data, cost-value recommendations are also provided for clinicians. Many recommendations from previously published guidelines have been updated with new evidence, and new recommendations have been created when supported by published data.

Coronary "Microvascular Dysfunction": Evolving Understanding of Pathophysiology, Clinical Implications, and Potential Therapeutics

Until recently, it has been generally held that stable angina pectoris (SAP) primarily reflects the presence of epicardial coronary artery stenoses due to atheromatous plaque(s), while acute myocardial infarction (AMI) results from thrombus formation on ruptured plaques. This concept is now challenged, especially by results of the ORBITA and ISCHEMIA trials, which showed that angioplasty/stenting does not substantially relieve SAP symptoms or prevent AMI or death in such patients. These disappointing outcomes serve to redirect attention towards anomalies of small coronary physiology. Recent studies suggest that coronary microvasculature is often both structurally and physiologically abnormal irrespective of the presence or absence of large coronary artery stenoses. Structural remodelling of the coronary microvasculature appears to be induced primarily by inflammation initiated by mast cell, platelet, and neutrophil activation, leading to erosion of the endothelial glycocalyx. This leads to the disruption of laminar flow and the facilitation of endothelial platelet interaction. Glycocalyx shedding has been implicated in the pathophysiology of coronary artery spasm, cardiovascular ageing, AMI, and viral vasculitis. Physiological dysfunction is closely linked to structural remodelling and occurs in most patients with myocardial ischemia, irrespective of the presence or absence of large-vessel stenoses. Dysfunction includes the impairment of platelet and vascular responsiveness to autocidal coronary vasodilators, such as nitric oxide, prostacyclin, and hydrogen sulphide, and predisposes both to coronary vasoconstriction and to a propensity for microthrombus formation. These findings emphasise the need for new directions in medical therapeutics for patients with SAP, as well as a wide range of other cardiovascular disorders.

Coronary revascularization for heart failure with coronary artery disease: A systematic review and meta-analysis of randomized trials

AIMS

Coronary artery disease (CAD) is a common cause of heart failure (HF). Whether coronary revascularization improves outcomes in patients with HF receiving guideline-recommended pharmacological therapy (GRPT) remains uncertain; therefore, we conducted a systematic review and meta-analysis of relevant randomized controlled trials (RCTs).

METHODS AND RESULTS

We searched in public databases for RCTs published between 1 January 2001 and 22 November 2022, investigating the effects of coronary revascularization on morbidity and mortality in patients with chronic HF due to CAD. All-cause mortality was the primary outcome. We included five RCTs that enrolled, altogether, 2842 patients (most aged <65 years; 85% men; 67% with left ventricular ejection fraction ≤35%). Overall, compared to medical therapy alone, coronary revascularization was associated with a lower risk of all-cause mortality (hazard ratio [HR] 0.88, 95% confidence interval [CI] 0.79-0.99; p = 0.0278) and cardiovascular mortality (HR 0.80, 95% CI 0.70-0.93; p = 0.0024) but not the composite of hospitalization for HF or all-cause mortality (HR 0.87, 95% CI 0.74-1.01; p = 0.0728). There were insufficient data to show whether the effects of coronary artery bypass graft surgery or percutaneous coronary intervention were similar or differed.

CONCLUSIONS

For patients with chronic HF and CAD enrolled in RCTs, the effect of coronary revascularization on all-cause mortality was statistically significant but neither substantial (HR 0.88) nor robust (upper 95% CI close to 1.0). RCTs were not blinded, which may bias reporting of the cause-specific reasons for hospitalization and mortality. Further trials are required to determine which patients with HF and CAD obtain a substantial benefit from coronary revascularization by either coronary artery bypass graft surgery or percutaneous coronary intervention.

Deferred Versus Performed Revascularization for Left Main Coronary Disease With Hemodynamic Significance

BACKGROUND

The majority of randomized controlled trials of revascularization decision-making excludes left main coronary artery disease (LMD). Therefore, contemporary clinical outcomes of patients with stable coronary artery disease and LMD with proven ischemia remain poorly understood. The aim of this study was to assess the long-term clinical outcomes of physiologically significant LMD according to the treatment strategies of revascularization versus revascularization deferral.

METHODS

In this international multicenter registry of stable LMD interrogated with the instantaneous wave-free ratio, patients with physiologically significant ischemia (instantaneous wave-free ratio ≤0.89) were analyzed according to the coronary revascularization (n=151) versus revascularization deferral (n=74). Propensity score matching was performed to adjust for baseline clinical characteristics. The primary end point was a composite of death, nonfatal myocardial infarction, and ischemia-driven target lesion revascularization of left main stem. The secondary end points were as follows: cardiac death or spontaneous LMD-related myocardial infarction; and ischemia-driven target lesion revascularization of left main stem.

RESULTS

At a median follow-up period of 2.8 years, the primary end point occurred in 11 patients (14.9%) in the revascularized group and 21 patients (28.4%) in the deferred group (hazard ratio, 0.42 [95% CI, 0.20-0.89]; P=0.023). For the secondary end points, cardiac death or LMD-related myocardial infarction occurred significantly less frequently in the revascularized group (0.0% versus 8.1%; P=0.004). The rate of ischemia-driven target lesion revascularization of left main stem was also significantly lower in the revascularized group (5.4% versus 17.6%; hazard ratio, 0.20 [95% CI, 0.056-0.70]; P=0.012).

CONCLUSIONS

In patients who underwent revascularization for stable coronary artery disease and physiologically significant LMD determined by instantaneous wave-free ratio, the long-term clinical outcomes were significantly improved as compared with those in whom revascularization was deferred.

Identification of immune-related genes in acute myocardial infarction based on integrated bioinformatical methods and experimental verification

Background

Acute myocardial infarction (AMI) is one of the leading causes of death worldwide. The etiology of AMI is complex and has not been fully defined. In recent years, the role of immune response in the development, progression and prognosis of AMI has received increasing attention. The aim of this study was to identify key genes associated with the immune response in AMI and to analyze their immune infiltration.

Methods

The study included a total of two GEO databases, containing 83 patients with AMI and 54 healthy individuals. We used the linear model of microarray data (limma) package to find the differentially expressed genes associated with AMI, performing weighted gene co-expression analysis (WGCNA) to further identify the genes associated with inflammatory response to AMI. We found the final hub genes through the protein-protein interaction (PPI) network and least absolute shrinkage and selection operator (LASSO) regression model. To verify the above conclusions, we constructed mice AMI model, extracting myocardial tissue to perform qRT-PCR. Furthermore, the CIBERSORT tool for immune cells infiltration analysis was also carried out.

Results

A total of 5,425 significant up-regulated and 2,126 down-regulated genes were found in GSE66360 and GSE24519. A total of 116 immune-related genes in close association with AMI were screened by WGCNA analysis. These genes were mostly clustered in the immune response on the basis of GO and KEGG enrichment. With construction of PPI network and LASSO regression analysis, this research found three hub genes (SOCS2, FFAR2, MYO10) among these differentially expressed genes. The immune cell infiltration results revealed that significant differences could be found on T cells CD4 memory activated, Tregs (regulatory T cells), macrophages M2, neutrophils, T cells CD8, T cells CD4 naive, eosinophils between controls and AMI patients.

T-Wave Analysis on the 24 h Holter ECG Monitoring as a Predictive Assessment of Major Adverse Cardiovascular Events in Patients with Myocardial Infarction: A Literature Review and Future Perspectives

Myocardial ischemia is a pathophysiological state characterized by inadequate perfusion of the myocardium, resulting in an imbalance between myocardial oxygen demand and supply. It is most commonly caused by coronary artery disease, in which atherosclerotic plaques lead to luminal narrowing and reduced blood flow to the heart. Myocardial ischemia can manifest as angina pectoris or silent myocardial ischemia and can progress to myocardial infarction or heart failure if left untreated. Diagnosis of myocardial ischemia typically involves a combination of clinical evaluation, electrocardiography and imaging studies. Electrocardiographic parameters, as assessed by 24 h Holter ECG monitoring, can predict the occurrence of major adverse cardiovascular events in patients with myocardial ischemia, independent of other risk factors. The T-waves in patients with myocardial ischemia have prognostic value for predicting major adverse cardiovascular events, and their electrophysiological heterogeneity can be visualized using various techniques. Combining the electrocardiographic findings with the assessment of myocardial substrate may offer a better picture of the factors that can contribute to cardiovascular death.

Mechanisms of Xuefu Zhuyu Decoction in the treatment of coronary heart disease based on integrated metabolomics and network pharmacology approach

Coronary heart disease (CHD) has become the leading cause of mortality, morbidity, and disability worldwide. Though the therapeutic effect of Xuefu Zhuyu Decoction (XFZY) on CHD has been demonstrated in China, the active ingredients and molecular mechanisms of XFZY have not been elucidated. The purpose of the current study is to explore the molecular mechanisms of XFZY in the treatment of CHD via network pharmacology, metabolomics, and experimental validation. First, we established a CHD rat model by permanently ligating the left anterior descending coronary artery (LAD), and evaluated the therapeutic effect of XFZY by hemorheology and histopathology. Second, network pharmacology was employed to screen the active ingredients and potential targets of XFZY for the treatment of CHD. Metabolomic was applied to identify the molecules present in the serum after XFZY treatment. Third, the results of network pharmacology and metabolomics were further analyzed by Cytoscape to elucidate the core ingredients and pathways. Finally, the obtained key pathways were verified by transmission electron microscopy and immunofluorescence assay. The results showed that XFZY was effective in the treatment of CHD in the rat model, and the highest dose exerted the best effect. Network pharmacology analysis revealed 215 active ingredients and 129 key targets associated with XFZY treatment of CHD. These targets were enriched in pathways of cancer, lipid and atherosclerosis, fluid shear stress and atherosclerosis, proteoglycans in cancer, chemical carcinogenesis - receptor activation, HIF-1 signaling, et al. Serum metabolomic identified 1081 metabolites involved in the therapeutic effect of XFZY on CHD. These metabolites were enriched in taurine and hypotaurine metabolism, histidine metabolism, retrograde endocannabinoid signaling pathways, et al. Cytoscape analysis combining the data from serum metabolomic and network pharmacology revealed that energy metabolism as the core pathway for XFZY treatment of CHD. Electron microscope observation identified changes in the level of autophagy in the mitochondrial structure of cardiomyocytes. Immunofluorescence assay showed that the expression levels of autophagy-related proteins LC3-B and P62/SQSTM1 were consistent with the levels of autophagy observed in mitochondria. In conclusion, our findings suggest that the possible mechanisms of XFZY in the treatment of CHD are reducing the level of autophagy, improving energy metabolism, and maintaining mitochondrial homeostasis in cardiomyocytes. Our study also shows that the combined strategies of network pharmacology, metabolomics, and experimental validation may provide a powerful approach for TCM pharmacology study.

Periprocedural myocardial infarction in patients undergoing percutaneous coronary intervention

Percutaneous coronary intervention (PCI) in addition to guideline-directed medical therapy reduces the risk of spontaneous myocardial infarction (MI), urgent revascularization, and improves angina status; however, PCI is associated with an increased risk of periprocedural myocardial injury and MI. Numerous studies have investigated the mechanisms, predictors, and therapeutic strategies for periprocedural MI. Various definitions of periprocedural MI have been proposed by academic groups and professional societies requiring different cardiac biomarker thresholds and ancillary criteria for myocardial ischemia. The frequency and clinical significance of periprocedural MI substantially varies according to the definitions applied. In daily practice, accurate diagnosis of clinically-relevant periprocedural MI is essential because it may have a substantial impact on subsequent patient management. In the clinical trial setting, only clinically relevant periprocedural MI definitions should be applied as a clinical endpoint in order to avoid obscuring meaningful outcomes. In this review, we aim to summarize the mechanisms, predictors, frequency, and prognostic impact of periprocedural MI in patients undergoing PCI and to provide the current perspective on this issue.

Long-term follow-up after invasive or conservative management of stable coronary disease: the ISCHEMIA-EXTEND study

The ISCHEMIA trial found no statistical difference in the primary endpoint between initial invasive and conservative management of patients with chronic coronary disease and moderate-to-severe ischaemia on stress testing. However, an invasive strategy increased peri-procedural myocardial infarction (MI) but decreased spontaneous MI with continued separation of curves over time. Thus, in order to assess the long-term effect of invasive management strategy on mortality, the ISCHEMIA-EXTEND observational study was planned including surviving participants from the initial phase of the ISCHEMIA trial with a projected median follow-up of nearly 10 years. Recently, an interim report of 7-year all-cause, cardiovascular (CV), and non-CV mortality rates has been published showing no difference in all-cause mortality between the two strategies, but with a lower risk of CV mortality and higher risk of non-CV mortality with an initial invasive strategy over a median follow-up of 5.7 years. The trade-offs in CV and non-CV mortality observed in ISCHEMIA-EXTEND raise many important questions regarding the heterogeneity of treatment effect, the drivers of mortality, and the relative importance and reliability of CV vs. all-cause mortality. Overall, findings from ISCHEMIA and ISCHEMIA-EXTEND trials might help physicians in shared decision-making as to whether to add invasive management to guideline-directed medical management in selected patients with chronic coronary artery disease and moderate or severe ischaemia.

Relationship Between the Completeness of Revascularization and Myocardial Injury in Patients Treated With Percutaneous Coronary Intervention

BACKGROUND

Clinical outcomes of patients suffering periprocedural myocardial injury and undergoing incomplete revascularization (IR) following percutaneous coronary intervention (PCI) has never been investigated.

OBJECTIVE

To investigate the relationship between different thresholds of post-PCI cardiac troponin (cTn) elevation and revascularization completeness in determining long-term clinical outcomes.

METHODS

Patients were stratified in tertiles according to preprocedural SYNTAX score (SS) (low: 0-6; medium: >6-11; high: >11) and residual SS (low: 0-4; medium: >4-8; high: >8). IR was defined by a rSS value >4. Three thresholds of myocardial injury were pre-specified: 5×, 35× and 70× 99th percentile upper reference limit (URL) increase of baseline cTn. Primary outcome was a composite of major adverse cardiac events (MACE) at two years of follow-up.

RESULTS

1061 patients undergoing PCI for stable coronary artery disease were enrolled. IR occurred in 249 (23.4 %) and major myocardial injury in 540 (50.9 %). Patients belonging to the highest tertile of SS showed an increased risk of experiencing IR and periprocedural myocardial injury. Two-year follow-up was available in 869. At multi-variate Cox's regression analysis, patients undergoing IR + cTn > 35 × URL and IR + cTn > 70 × URL showed an increased risk of MACE [HR 2.30 (1.19-4.41) and HR 3.20 (1.38-7.41); respectively].

CONCLUSIONS

Periprocedural myocardial injury is critically associated with MACE at two-year follow-up in patient treated with PCI who achieve IR. Despite conflicting evidence exists regarding the influence of periprocedural myocardial injury on clinical outcomes, patients undergoing IR seem to represent a high-risk subgroup.

Clinical application of results of the ISCHEMIA trial

More than a decade after the Clinical Outcomes Utilising Revascularization and Aggressive Drug Evaluation (COURAGE) trial, International Study of Comparative Health Effectiveness With Medical And Invasive Approaches (ISCHEMIA) is the second large clinical trial to challenge the concept of revascularization in chronic coronary syndromes whilst addressing some of the shortfalls of its predecessor.

Fundamental Pathobiology of Coronary Atherosclerosis and Clinical Implications for Chronic Ischemic Heart Disease Management-The Plaque Hypothesis: A Narrative Review

Importance

Recent clinical and imaging studies underscore that major adverse cardiac events (MACE) outcomes are associated not solely with severe coronary obstructions (ischemia hypothesis or stenosis hypothesis), but with the plaque burden along the entire coronary tree. New research clarifies the pathobiologic mechanisms responsible for plaque development/progression/destabilization leading to MACE (plaque hypothesis), but the translation of these insights to clinical management strategies has lagged. This narrative review elaborates the plaque hypothesis and explicates the current understanding of underlying pathobiologic mechanisms, the provocative destabilizing influences, the diagnostic and therapeutic implications, and their actionable clinical management approaches to optimize the management of patients with chronic coronary disease.

Observations

Clinical trials of management strategies for patients with chronic coronary artery disease demonstrate that while MACE rate increases progressively with the anatomic extent of coronary disease, revascularization of the ischemia-producing obstruction does not forestall MACE. Most severely obstructive coronary lesions often remain quiescent and seldom destabilize to cause a MACE. Coronary lesions that later provoke acute myocardial infarction often do not narrow the lumen critically. Invasive and noninvasive imaging can identify the plaque anatomic characteristics (plaque burden, plaque topography, lipid content) and local hemodynamic/biomechanical characteristics (endothelial shear stress, plaque structural stress, axial plaque stress) that can indicate the propensity of individual plaques to provoke a MACE.

Conclusions and Relevance

The pathobiologic construct concerning the culprit region of a plaque most likely to cause a MACE (plaque hypothesis), which incorporates multiple convergent plaque features, informs the evolution of a new management strategy capable of identifying the high-risk portion of plaque wherever it is located along the course of the coronary artery. Ongoing investigations of high-risk plaque features, coupled with technical advances to enable prognostic characterization in real time and at the point of care, will soon enable evaluation of the entire length of the atheromatous coronary artery and broaden the target(s) of our therapeutic intervention to include all regions of the plaque (both flow limiting and nonflow limiting).

Survival After Invasive or Conservative Management of Stable Coronary Disease

BACKGROUND

The ISCHEMIA trial (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches) compared an initial invasive versus an initial conservative management strategy for patients with chronic coronary disease and moderate or severe ischemia, with no major difference in most outcomes during a median of 3.2 years. Extended follow-up for mortality is ongoing.

METHODS

ISCHEMIA participants were randomized to an initial invasive strategy added to guideline-directed medical therapy or a conservative strategy. Patients with moderate or severe ischemia, ejection fraction ≥35%, and no recent acute coronary syndromes were included. Those with an unacceptable level of angina were excluded. Extended follow-up for vital status is being conducted by sites or through central death index search. Data obtained through December 2021 are included in this interim report. We analyzed all-cause, cardiovascular, and noncardiovascular mortality by randomized strategy, using nonparametric cumulative incidence estimators, Cox regression models, and Bayesian methods. Undetermined deaths were classified as cardiovascular as prespecified in the trial protocol.

RESULTS

Baseline characteristics for 5179 original ISCHEMIA trial participants included median age 65 years, 23% women, 16% Hispanic, 4% Black, 42% with diabetes, and median ejection fraction 0.60. A total of 557 deaths accrued during a median follow-up of 5.7 years, with 268 of these added in the extended follow-up phase. This included a total of 343 cardiovascular deaths, 192 noncardiovascular deaths, and 22 unclassified deaths. All-cause mortality was not different between randomized treatment groups (7-year rate, 12.7% in invasive strategy, 13.4% in conservative strategy; adjusted hazard ratio, 1.00 [95% CI, 0.85-1.18]). There was a lower 7-year rate cardiovascular mortality (6.4% versus 8.6%; adjusted hazard ratio, 0.78 [95% CI, 0.63-0.96]) with an initial invasive strategy but a higher 7-year rate of noncardiovascular mortality (5.6% versus 4.4%; adjusted hazard ratio, 1.44 [95% CI, 1.08-1.91]) compared with the conservative strategy. No heterogeneity of treatment effect was evident in prespecified subgroups, including multivessel coronary disease.

CONCLUSIONS

There was no difference in all-cause mortality with an initial invasive strategy compared with an initial conservative strategy, but there was lower risk of cardiovascular mortality and higher risk of noncardiovascular mortality with an initial invasive strategy during a median follow-up of 5.7 years.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT04894877.

Additive Effect of Multiple High-Risk Coronary Artery Segments on Patient Outcomes: LRP Study Sub-Analysis

BACKGROUND

The Lipid Rich Plaque (LRP) Study established the association between high volume of lipidic content (maximum Lipid Core Burden Index [maxLCBI_4mm] >400) in the coronary arteries and subsequent non-culprit major adverse cardiac events (NC-MACE). This analysis sought to assess the clinical impact of more than one lipid-rich plaque in the coronary tree.

METHODS

The LRP patient population was divided into four cohorts: 1) patients with all segments with maxLCBI_4mm = 0; 2) patients with all coronary segments maxLCBI_4mm < 400, but >0; 3) patients with 1 segment maxLCBI_4mm > 400; and 4) patients with 2+ coronary segments with maxLCBI_4mm > 400. Baseline characteristics, plaque-level characteristics, and follow-up outcomes were described.

RESULTS

Among 1550 patients, only 3.2 % had all segments with maxLCBI_4mm = 0; 65.1 % had segments with maxLCBI_4mm > 0 but <400; 22.5 % had one segment with maxLCBI_4mm > 400; and 9.5 % had 2+ coronary segments with maxLCBI_4mm > 400. Distribution within the coronary tree (one versus multiple arteries) did not differ. Overall, 1269 patients were allocated to follow-up (per study design). The composite of all-cause death, cardiac death, any revascularization, and NC-MACE was statistically higher in patients with 1 segment maxLCBI_4mm > 400 and numerically even higher in patients with 2+ segments with maxLCBI_4mm > 400. Patients with maxLCBI_4mm = 0 had no events within two years.

CONCLUSION

There is a stepwise increased risk of all-cause death, cardiac death, any revascularization, and NC-MACE according to the number of coronary segments with maxLCBI_4mm > 400. In contrast, maxLCBI_4mm = 0 results in a low event rate.

CLINICAL TRIAL REGISTRATION

The Lipid-Rich Plaque Study (LRP), https://clinicaltrials.gov/ct2/show/NCT02033694, NCT02033694.

What About All the Recent "Negative" FFR Trials?

During the past 30 years, fractional flow reserve (FFR) has moved from animal models to class IA recommendations in guidelines. However, the FLOWER-MI, RIPCORD-2, FUTURE, and FAME 3 trials in 2021 were "negative"-has FFR exceeded its expiration date? We critically examine these randomized trials in order to draw insights not just about FFR but also about study design and interpretation. Are all randomized trials created equal? No, rather we must focus on discordant decisions between angiography and FFR and highlight clinical endpoints that can be improved by percutaneous coronary intervention instead of medical therapy.

Peri-Procedural Troponin Elevation after Percutaneous Coronary Intervention for Left Main Coronary Artery Disease

Left main (LM) percutaneous coronary interventions (PCI) are challenging and highly invasive procedures. Periprocedural myocardial injury (Troponin (Tn) elevation > 99th percentile) is frequently detected after LM PCI, being identified even in up to 67% of patients. However, the prognostic implications of periprocedural Tn elevation after LM PCI remain controversial. We aim to assess the impact and prognostic significance of the periprocedural troponin elevation on long-term outcomes in patients undergoing LM PCI in a real-world setting. Consecutive 673 patients who underwent LM PCI in our department between January 2015 to February 2021 were included in a prospective registry. The first group consisted of 323 patients with major cardiac Troponin I elevation defined as an elevation of Tn values > 5× the 99th percentile in patients with normal baseline values or post-procedure Tn rise by >20% in patients with elevated pre-procedure Tn in whom the Tn level was stable or falling (based on the fourth universal definition of myocardial infarction). The second group consisted of patients without major cardiac Troponin I elevation. Seven-year long-term all-cause mortality was not higher in the group with major Tn elevation (36.9% vs. 40.6%; p = 0.818). Naturally, periprocedural myocardial infarction was diagnosed only in patients from groups with major Tn elevation (4.9% of all patients). In-hospital death and other periprocedural complications did not differ significantly between the two study groups. The adjusted HRs for mortality post-PCI in patients with a periprocedural myocardial infarction were not significant. Long-term mortality subanalysis for the group with criteria for cardiac procedural myocardial injury showed no significant differences (39.5% vs. 38.8%; p = 0.997). The occurrence of Tn elevation (>1×; >5×; >35× and >70× URL) after LM PCI was not associated with adverse long-term outcomes. The results of the study suggest that the isolated periprocedural troponin elevation is not clinically significant.

Comparison of Outcomes of Invasive or Conservative Management of Chronic Coronary Disease in Four Randomized Controlled Trials

Revascularization and medical therapy for chronic coronary disease have both evolved significantly over the last 50 years. A total of 4 contemporary randomized controlled trials- Clinical Outcomes Utilizing Revascularization and Aggressive drug Evaluation (COURAGE), Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D), Fractional Flow Reserve versus Angiography for Multivessel Evaluation 2 (FAME 2), and International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA)-have assessed the incremental benefit of revascularization when added to secondary prevention with intensive pharmacologic and lifestyle intervention. We reviewed these 4 seminal studies with the objective of marshaling evidence to better frame how these results should apply to clinical decision making. These studies differed in study design, end points, intensity of treatment, and revascularization techniques. Nevertheless, they all demonstrate similar rates of "hard" clinical events with invasive and conservative management, and varying degrees of benefit in angina-related quality of life with revascularization. In conclusion, although controversy persists concerning the role of revascularization because of differing interpretations of the clinical trial evidence, we contend that instead of being competing management strategies, invasive and conservative approaches are complementary.

ISCHEMIA-EXTEND studies: Rationale and design

BACKGROUND

The ISCHEMIA and the ISCHEMIA-CKD trials found no statistical difference in the primary clinical endpoint between initial invasive management and initial conservative management of patients with chronic coronary disease and moderate to severe ischemia on stress testing without or with advanced chronic kidney disease (CKD). In ISCHEMIA, there was numerically lower cardiovascular mortality but higher non-cardiovascular mortality with no significant difference in all-cause death with an initial invasive strategy when compared with a conservative strategy. However, an invasive strategy increased peri-procedural myocardial infarction (MI) but decreased spontaneous MI with continued separation of curves over time, which potentially may lead to reduced risk of cardiovascular and all-cause mortality. Thus, the long-term effect of invasive management strategy on mortality remains unclear. In ISCHEMIA-CKD, the treatment and cause-specific mortality rates were similar during follow-up.

METHODS

Funded by the National Heart, Lung, and Blood Institute, the ISCHEMIA-EXTEND observational study is the long-term follow-up of surviving participants (projected median of 10 years) with chronic coronary disease from the ISCHEMIA trial. In the ISCHEMIA trial, 5,179 participants with moderate or severe stress-induced ischemia were randomized to initial invasive management with angiography, revascularization when feasible, and guideline-directed medical therapy (GDMT), or initial conservative management with GDMT alone and angiography reserved for failure of medical therapy. ISCHEMIA-CKD EXTEND is the long-term follow-up of surviving participants (projected median of 9 years) from the ISCHEMIA-CKD trial, a companion trial that included 777 patients with advanced CKD. Ascertainment of death will be conducted via direct participant contact, medical record review, and/or vital status registry search. The overarching objective of long-term follow-up is to assess whether there are between-group differences in long-term all-cause, cardiovascular, and non-cardiovascular mortality, and increase precision around the treatment effect estimates for risk of all-cause, cardiovascular, and non-cardiovascular mortality. We will conduct Bayesian survival modeling to take advantage of rich inferences using the posterior distribution of the treatment effect.

CONCLUSIONS

The long-term effect of an initial invasive versus conservative strategy on all-cause, cardiovascular, and non-cardiovascular mortality will be assessed. The findings of ISCHEMIA-EXTEND and ISCHEMIA-CKD EXTEND will inform patients, practitioners, practice guidelines, and health policy.

Shared decision-making in the realm of uncertainty: The example of coronary artery disease through an EBM and complexity science lens

Patients look to their clinicians for explanations and treatments that achieve predictable cures with certainty. Clinicians usually respond accordingly. Acknowledging uncertainty, while necessary, is difficult, anxiety-provoking and at times overwhelming for patients and clinicians alike. We here present three case studies to illustrate the uncertainties of managing patients with potentially life-threatening illnesses. Research aims to provide answers to clinical problems. But, conducting research almost inevitably entails a reduction of real-world complexities. Research ultimately can only provide 'partial or in general answers' mostly revealing new questions. Due to the complexity of clinical care, research cannot really achieve certainty and predictability for an individual within his specific living context and values. In an unavoidably uncertain environment, instead of oversimplifying, clinicians like patients-as far as possible-ought to better embrace a complexity thinking frame. This provides a deeper understanding how living bodies function as-a-whole within their living contexts. Uncertainty and unpredictability, being inherent elements of complexity thinking, cannot be overcome. However, it may be made easier to cope with uncertainty by at least adopting the thinking in probabilities for benefits and harms of patient related outcomes as introduced in Sackett's Evidence-Based Medicine framework. Through the lenses of evidence-based medicine and complexity sciences this paper critically explores the clinical management of three patients diagnosed as having coronary artery disease. They all received the same treatment even though they presented with very different clinical complaints arising from different disease manifestations. Looking at these case studies the authors reflect on the reasons behind this astonishing, but widely seen medical behaviour of 'one size fits all'. They critically reflect the importance of research and evidence in view of a person-centred solution.

Prognostic value of high-sensitivity cardiac troponin I early after coronary artery bypass graft surgery

BACKGROUND

The diagnosis of periprocedural myocardial infarction (PMI) after coronary artery bypass graft (CABG) is based on biochemical markers along with clinical and instrumental findings. However, there is not a clear cutoff value of high-sensitivity cardiac troponin (hs-cTn) to identify PMI. We hypothesized that isolated hs-cTn concentrations in the first 24 h following CABG could predict cardiac adverse events (in-hospital death and PMI) and/or left ventricular ejection fraction (LVEF) decrease.

METHODS

We retrospectively enrolled all consecutive adult patients undergoing CABG, alone or in association with other cardiac surgery procedures, over 1 year. Hs-cTn I concentrations (Access, Beckman Coulter) were serially measured in the post-operative period and analyzed according to post-operative outcomes.

RESULTS

300 patients were enrolled; 71.3% underwent CABG alone, 33.7% for acute coronary syndrome. Most patients showed hs-cTn I values superior to the limit required by the latest guidelines for the diagnosis of PMI. Five patients (1.7%) died, 8% developed a PMI, 10.6% showed a LVEF decrease ≥ 10%. Hs-cTn I concentrations did not significantly differ with respect to death and/or PMI whereas they were associated with LVEF decrease ≥ 10% (p value < 0.005 at any time interval), in particular hs-cTn I values at 9-12 h post-operatively. A hs-cTn I cutoff of 5556 ng/L, a value 281 (for males) and 479 (for females) times higher than the URL, at 9-12 h post-operatively was identified, representing the best balance between sensitivity (55%) and specificity (79%) in predicting LVEF decrease ≥ 10%.

CONCLUSIONS

Hs-cTn I at 9-12 h post-CABG may be useful to early identify patients at risk for LVEF decrease and to guide early investigation and management of possible post-operative complications.

Mechanisms and Definitions of Periprocedural Myocardial Infarction in the Era of Modern Revascularization

One of the most frequent complications following coronary revascularization is cardiac myonecrosis characterized by an elevation of cardiac biomarkers, particularly with the implementation of high-sensitivity cardiac troponin. In the last decades, various definitions of periprocedural myocardial injury and infarction have been proposed, based on different cardiac biomarkers, various thresholds, and the need for additional ischemic features. In this review, we aim at providing insights on the mechanisms involved in periprocedural myocardial injury and infarction following percutaneous coronary intervention or coronary artery bypass grafting, the strengths and limitations of the available definitions and their clinical implications. We also provide an updated description of preventive strategies that have been evaluated in randomized controlled trials to avoid these complications as well as patient-level and lesion-level risk factors to better anticipate and rebalance the indication for coronary revascularization and plan adequate post-procedure monitoring.