Managing Stable Ischemic Heart Disease

Characterization of a novel mitophagy-related 5-genes signature for diagnosis of acute myocardial infarction

Myocardial infarction (MI) and the ensuing heart failure (HF) remain the main cause of morbidity and mortality worldwide. One of the strategies to combat MI and HF lies in the ability to accurately predict the onset of these disorders. Alterations in mitochondrial homeostasis have been reported to be involved in the pathogenesis of various cardiovascular diseases (CVDs). In this regard, perturbations to mitochondrial dynamics leading to impaired clearance of dysfunctional mitochondria have been previously established to be a crucial trigger for MI/HF. In this study, we found that MI patients could be classified into three clusters based on the expression levels of mitophagy-related genes and consensus clustering. We identified a mitophagy-related diagnostic 5-genes signature for MI using support vector machines-Recursive Feature Elimination (SVM-RFE) and random forest, with the area under the ROC curve (AUC) value of the predictive model at 0.813. Additionally, the single-cell transcriptome and pseudo-time analyses showed that the mitoscore was significantly upregulated in macrophages, endothelial cells, pericytes, fibroblasts and monocytes in patients with ischemic cardiomyopathy, while sequestosome 1 (SQSTM1) exhibited remarkable increase in the infarcted (ICM) and non-infarcted (ICMN) myocardium samples dissected from the left ventricle compared with control samples. Lastly, through analysis of peripheral blood from MI patients, we found that the expression of SQSTM1 is positively correlated with troponin-T (P < 0.0001, R = 0.4195, R2 = 0.1759). Therefore, this study provides the rationale for a cell-specific mitophagy-related gene signature as an additional supporting diagnostic for CVDs.

A novel radiomics-based technique for identifying vulnerable coronary plaques: a follow-up study

BACKGROUND

Previous reports have suggested that coronary computed tomography angiography (CCTA)-based radiomics analysis is a potentially helpful tool for assessing vulnerable plaques. We aimed to investigate whether coronary radiomic analysis of CCTA images could identify vulnerable plaques in patients with stable angina pectoris.

METHODS

This retrospective study included patients initially diagnosed with stable angina pectoris. Patients were randomly divided into either the training or test dataset at an 8 : 2 ratio. Radiomics features were extracted from CCTA images. Radiomics models for predicting vulnerable plaques were developed using the support vector machine (SVM) algorithm. The model performance was assessed using the area under the curve (AUC); the accuracy, sensitivity, and specificity were calculated to compare the diagnostic performance using the two cohorts.

RESULTS

A total of 158 patients were included in the analysis. The SVM radiomics model performed well in predicting vulnerable plaques, with AUC values of 0.977 and 0.875 for the training and test cohorts, respectively. With optimal cutoff values, the radiomics model showed accuracies of 0.91 and 0.882 in the training and test cohorts, respectively.

CONCLUSION

Although further larger population studies are necessary, this novel CCTA radiomics model may identify vulnerable plaques in patients with stable angina pectoris.

Pharmacokinetic-Pharmacodynamic Correlation Analysis of Rhodiola crenulata in Rats with Myocardial Ischemia

The pharmacokinetics (PK) of Rhodiola crenulata in rats were studied, and pharmacokinetic-pharmacodynamic (PK-PD) correlation analysis was performed to elucidate their time-concentration-effect relationship. The myocardial ischemia model was made with pituitrin. Rats were divided into sham operation, sham operation administration, model, and model administration groups (SG, SDG, MG, and MDG, respectively; n = 6). Blood was collected from the fundus venous plexus at different time points after oral administration. The HPLC-QQQ-MS/MS method was established for the quantification of five components of Rhodiola crenulata. CK, HBDH, SOD, LDH, and AST at different time points were detected via an automatic biochemical analyzer. DAS software was used to analyze PK parameters and PK-PD correlation. The myocardial ischemia model was established successfully. There were significant differences in the PK parameters (AUC0-t, AUC0-∞, Cmax) in MDG when compared with SDG. Two PD indicators, CK and HBDH, conforming to the sigmoid-Emax model, had high correlation with the five components, which indicated a delay in the pharmacological effect relative to the drug concentration in plasma. The difference in the PK parameters between modeled and normal rats was studied, and the time-concentration-effect of composition and effect indicators were investigated. This study can provide reference for the rational clinical application of Rhodiola crenulata and for related studies of other anti-myocardial ischemia drugs.

Nonischemic or Dual Cardiomyopathy in Patients With Coronary Artery Disease

BACKGROUND

Randomized trials in obstructive coronary artery disease (CAD) have largely shown no prognostic benefit from coronary revascularization. Although there are several potential reasons for the lack of benefit, an underexplored possible reason is the presence of coincidental nonischemic cardiomyopathy (NICM). We investigated the prevalence and prognostic significance of NICM in patients with CAD (CAD-NICM).

METHODS

We conducted a registry study of consecutive patients with obstructive CAD on coronary angiography who underwent contrast-enhanced cardiovascular magnetic resonance imaging for the assessment of ventricular function and scar at 4 hospitals from 2004 to 2020. We identified the presence and cause of cardiomyopathy using cardiovascular magnetic resonance imaging and coronary angiography data, blinded to clinical outcomes. The primary outcome was a composite of all-cause death or heart failure hospitalization, and secondary outcomes were all-cause death, heart failure hospitalization, and cardiovascular death.

RESULTS

Among 3023 patients (median age, 66 years; 76% men), 18.2% had no cardiomyopathy, 64.8% had ischemic cardiomyopathy (CAD+ICM), 9.3% had CAD+NICM, and 7.7% had dual cardiomyopathy (CAD+dualCM), defined as both ICM and NICM. Thus, 16.9% had CAD+NICM or dualCM. During a median follow-up of 4.8 years (interquartile range, 2.9, 7.6), 1116 patients experienced the primary outcome. In Cox multivariable analysis, CAD+NICM or dualCM was independently associated with a higher risk of the primary outcome compared with CAD+ICM (adjusted hazard ratio, 1.23 [95% CI, 1.06-1.43]; P=0.007) after adjustment for potential confounders. The risks of the secondary outcomes of all-cause death and heart failure hospitalization were also higher with CAD+NICM or dualCM (hazard ratio, 1.21 [95% CI, 1.02-1.43]; P=0.032; and hazard ratio, 1.37 [95% CI, 1.11-1.69]; P=0.003, respectively), whereas the risk of cardiovascular death did not differ from that of CAD+ICM (hazard ratio, 1.15 [95% CI, 0.89-1.48]; P=0.28).

CONCLUSIONS

In patients with CAD referred for clinical cardiovascular magnetic resonance imaging, NICM or dualCM was identified in 1 of every 6 patients and was associated with worse long-term outcomes compared with ICM. In patients with obstructive CAD, coincidental NICM or dualCM may contribute to the lack of prognostic benefit from coronary revascularization.

Therapeutic Role of Chinese Medicine Targeting Nrf2/HO-1 Signaling Pathway in Myocardial Ischemia/Reperfusion Injury

Acute myocardial infarction (AMI), characterized by high incidence and mortality rates, poses a significant public health threat. Reperfusion therapy, though the preferred treatment for AMI, often exacerbates cardiac damage, leading to myocardial ischemia/reperfusion injury (MI/RI). Consequently, the development of strategies to reduce MI/RI is an urgent priority in cardiovascular therapy. Chinese medicine, recognized for its multi-component, multi-pathway, and multi-target capabilities, provides a novel approach for alleviating MI/RI. A key area of interest is the nuclear factor E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. This pathway is instrumental in regulating inflammatory responses, oxidative stress, apoptosis, endoplasmic reticulum stress, and ferroptosis in MI/RI. This paper presents a comprehensive overview of the Nrf2/HO-1 signaling pathway's structure and its influence on MI/RI. Additionally, it reviews the latest research on leveraging Chinese medicine to modulate the Nrf2/HO-1 pathway in MI/RI treatment.

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.

A Semi-Three-Dimensional Bioprinted Neurocardiac System for Tissue Engineering of a Cardiac Autonomic Nervous System Model

In this study, we designed a tissue-engineered neurocardiac model to help us examine the role of neuronal regulation and confirm the importance of neural innervation techniques for the regeneration of cardiac tissue. A three-dimensional (3D) bioprinted neurocardiac scaffold composed of a mixture of gelatin-alginate and alginate-genipin-fibrin hydrogels was developed with a 2:1 ratio of AC16 cardiomyocytes (CMs) and retinoic acid-differentiated SH-SY5Y neuronal cells (NCs) respectively. A unique semi-3D bioprinting approach was adopted, where the CMs were mixed in the cardiac bioink and printed using an anisotropic accordion design to mimic the physiological tissue architecture in vivo. The voids in this 3D structure were methodically filled in using a NC-gel mixture and crosslinked. Confocal fluorescent imaging using microtubule-associated protein 2 (MAP-2) and anticholine acetyltransferase (CHAT) antibodies for labeling the NCs and the MyoD1 antibody for the CMs revealed functional coupling between the two cell types in the final crosslinked structure. These data confirmed the development of a relevant neurocardiac model that could be used to study neurocardiac modulation under physiological and pathological conditions.

Effects of pre-operative education tailored to information-seeking styles on pre-operative anxiety and depression among patients undergoing percutaneous coronary intervention: A randomized controlled trial

Objective

This study aimed to evaluate the impact of pre-operative education tailored to percutaneous coronary intervention (PCI) patients' information-seeking styles on pre-operative anxiety and depression.

Methods

A single-blind randomized control trial was conducted. A total of 114 participants were recruited from the cardiology department in a tertiary hospital in Kunming, Southwest China from April to September 2020 and randomly allocated to the intervention group (n = 57) or control group (n = 57). All patients received oral pre-operative education as well as printed pre-operative education manuals and divided into monitors or blunters by the Chinese Version of the Monitoring Subscale of the Miller Behavioral Style Scale (C-MMBSS). The intervention group received pre-operative education tailored to information-seeking styles, while the control group received routine education. Anxiety and depression were measured at baseline and 1 h before the operation. Satisfaction with pre-operative education and length of stay were assessed at discharge.

Results

A total of 104 participants completed the study (52 participants in each group). Pre-operative education tailored to information-seeking styles was beneficial for reducing pre-operative anxiety (P < 0.01), reducing pre-operative depression (P < 0.01), and improving satisfaction with pre-operative education (P < 0.01) compared with routine education. There was no significant difference in length of stay between the intervention and control groups (P = 0.209). Conversely, pre-operative anxiety of patients was increased (P = 0.017) after pre-operative education in the control group.

Conclusion

This study confirmed that pre-operative education tailored to information-seeking styles effectively reduces pre-operative anxiety and depression and improves satisfaction with preoperative education.

MiR-144-5p/CCL12 Signaling Axis Modulates Ischemic Preconditioning-Mediated Cardio-protection by Reducing Cell Viability, Enhancing Cell Apoptosis, Fibrosis, and Pyroptosis

Ischemic postconditioning (IPost) represents short periods of nonlethal ischemia-reperfusion performed at the onset of reperfusion. Studies have shown that IPost involves various biological processes such as cell proliferation, apoptosis, and pyroptosis and can activate complex signaling pathways. CCL12 is a critical mediator in the inflammatory process after tissue injury. In the present study, we examined the potential actions of CCL12-mediated signaling pathways in cardioprotection after IPost using a cardiomyocyte model. By applying the bioinformatics analysis, we found that CCL12 was upregulated in the rat heart tissues after I/R injury, and the expression level of CCL12 was restored in rats with IPost. The in vitro studies showed that CCL12 and CCR2 expression levels were upregulated in the hypoxia/reoxygenation (H/R)-induced H9C2 cells, which was attenuated in the H/R + hypoxia post-conditioning (PostC) group. The functional assays showed that H/R treatment reduced cell viability, increased cell apoptosis, and promoted fibrosis and pyroptosis of H9C2 cells, which was attenuated in the H/R + PostC group. Overexpression of CCL12 impaired the protective action of hypoxia post-conditioning in the H9C2 cells. Further mechanistic studies showed that miR-144-5p could directly target the 3' untranslated region of CCL12. Overexpression of miR-144-5p markedly repressed the expression levels of CCL12 and CCR2 in H9C2 cells, while miR-144-5p inhibition had the opposite effects. Furthermore, the inhibition of miR-144-5p reduced the cell viability, increased cell apoptosis, and enhanced fibrosis and pyroptosis of H9C2 cells after H/R or H/R + PostC treatment. In conclusion, CCL12 was downregulated in cardiomyocytes following ischemic postconditioning, and CCL12 overexpression impaired the cardioprotective actions of ischemic postconditioning by reducing cell viability, enhancing cell apoptosis, fibrosis, and pyroptosis. Further mechanistic evidence revealed that CCL12 was a direct target of miR-144-5p, and miR-144-5p/CCL12/CCR2 signaling may represent a critical pathway in mediating the cardioprotective effects of ischemic postconditioning.

A risk model developed based on necroptosis to assess progression for ischemic cardiomyopathy and identify possible therapeutic drugs

Object: Ischemic cardiomyopathy (ICM), with high morbidity and mortality, is the most common cause of heart failure. Cardiovascular remodeling secondary to chronic myocardial ischemia is the main cause of its progression. A recently identified type of programmed cell death called necroptosis is crucial in the development of various cardiovascular diseases. However, the function role of necroptosis in cardiac remodeling of ICM has not been elucidated. Our study aimed to screen for genes associated with necroptosis and construct a risk score to assess the progression and evaluate the prognosis of ICM patients, and further to search for potentially therapeutic drugs. Methods: The gene expression profiling was obtained from the GEO database. LASSO regression analysis was used to construct necroptosis-related gene signatures associated with ICM progression and prognosis. TF-gene and miRNA-gene networks were constructed to identify the regulatory targets of potential necroptosis-related signature genes. Pathway alterations in patients with high necroptosis-related score (NRS) were analyzed by GO, KEGG, GSEA analysis, and immune cell infiltration was estimated by ImmuCellAI analysis. CMap analysis was performed to screen potential small molecule compounds targeting patients with high NRS. Independent risk analyses were performed using nomograms. Results: Six necroptosis-related signature genes (STAT4, TNFSF10, CHMP5, CHMP18, JAK1, and CFLAR) were used to define the NRS, with areas under the ROC curves of 0.833, 0.765, and 0.75 for training test, test set, and validation set, respectively. Transcription factors FOXC1 and hsa-miR-124-3p miRNA may be regulators of signature genes. Patients with higher NRS have pathway enriched in fibrosis and metabolism and elevated nTreg cells. AZD-7762 may be an effective drug to improve the prognosis of patients with high NRS. A feature-based nomogram was constructed from which patients could derive clinical benefit. Conclusion: Our results reveal 6 necroptosis gene signatures that can evaluate the progression and prognosis of ICM with high clinical value, and identify potential targets that could help improve cardiovascular remodeling.

Disease burden and risk factors of ischemic heart disease in China during 1990-2019 based on the Global Burden of Disease 2019 report: A systematic analysis

Objective

The aim of this study was to identify the disease burden and risk factors of ischemic heart disease (IHD) in China, during 1990-2019, through a systematic analysis using the Global Burden of Disease (GBD) 2019 report in order to provide first-hand information for primary and secondary prevention of IHD in China.

Methods

Data on the rates of incidence, death, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life years (DALYs) of IHD were obtained from GBD2019 to determine the disease burden and risk factors of IHD in China.

Results

The rates of incidence, death, YLLs, YLDs, and DALYs of IHD in China increased at different levels during 1990-2019. The annual rate of change in incidence, death, YLLs, YLDs, and DALYs of IHD were 1.31%, 1.57%, 0.93%, 1.14%, and 0.94%, respectively. In 2019, the YLDs of IHD in Chinese women were higher, while the rates of incidence and death, YLLs, and DALYs were lower in Chinese women than in Chinese men. The disease burden of IHD had significant age differences, and people aged ≥70 years had the highest disease burden. A total of 24 risk factors were associated with the rates of death and DALYs of IHD, and the five most significant risk factors were high systolic blood pressure, high LDL cholesterol (LDL-C), smoking, ambient particulate matter pollution, and intake of a high-sodium diet. From 1990 to 2019, a high annual rate of change in IHD-related deaths and DALYs was observed due to ambient particulate matter pollution, high body mass index (BMI), and intake of a diet high in processed meat.

Conclusion

The results of the study revealed that the disease burden of IHD in China was on the rise, especially in people aged ≥70 years. The main disease burden of IHD in male patients was premature death and that in female patients was disability. Environmental, behavioral, and metabolic factors were considered the three main risks of the disease burden of IHD, with metabolic factors having the greatest impact. Therefore, periodic health check-ups and high-risk factor interventions for key populations should be strengthened from the grassroots level, which are conducive to further reducing the disease burden of IHD in China.

Sodium Danshensu protects against oxygen glucose deprivation/reoxygenation-induced astrocytes injury through regulating NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome and tuberous sclerosis complex-2 (TSC2)/mammalian target of rapamycin (mTOR) pathways

BACKGROUND

Cerebral ischemic stroke is a serious condition with high incidence, mortality, and associated disability. Currently, effective therapeutic options are available for ischemic stroke are limited. Accumulating evidence indicates that sodium Danshensu, mono sodium compound derived from Salvia miltiorrhiza, plays protective roles in ischemic stroke. However, the underlying protective mechanism of sodium Danshensu in cerebral ischemic stroke remains unknown.

METHODS

In the current study, we explored the role and mechanism of sodium Danshensu on astrocytes exposed to oxygen-glucose deprivation/reoxygenation (OGD/R), which mimics the process of ischemia-reperfusion. The impact of sodium Danshensu on cell viability and apoptosis after OGD/R were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-dophenyl tetrazolium bromide (MTT) assay and flow cytometry. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot were used to detect the expression of target messenger RNA (mRNA) and proteins associated with apoptosis and autophagy. The release of lactate dehydrogenase (LDH) was determined, and the production of proinflammatory cytokines were detected using enzyme-linked immunosorbent assay (ELISA) kits.

RESULTS

It was found that sodium Danshensu could significantly increase cell viability and decrease LDH release and apoptosis. Besides, it inhibited the production of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6. Sodium Danshensu also dose-dependently decreased protein and mRNA levels of nucleotide binding oligomerization NOD-like receptor pyrin domain containing 3 (NLRP3) and high mobility group box 1 (HMGB1), which play a crucial role in promoting ischemic stroke-induced cell injury. Moreover, sodium Danshensu dose-dependently upregulated Beclin 1 expression, downregulated P62 protein expression, and further increased LC3B-II/LC3B-I ratio through inducing autophagy in astrocytes. Additionally, we noticed that sodium Danshensu dose-dependently increased tuberous sclerosis complex-2 (TSC2) protein expression, while significantly reduced the levels of mammalian target of rapamycin (mTOR) in the presence of OGD/R insult.

CONCLUSIONS

These findings suggest that sodium Danshensu protects against OGD/R-induced injury by modulating the NLRP3 inflammasome and TSC2/mTOR pathways.

Recanalisation of coronary chronic total occlusions

Percutaneous treatment of coronary chronic total occlusions (CTO) has advanced greatly since its advent in the late 1970s through the development of dedicated wires and microcatheters, the improved skills of highly experienced operators and the adoption of new sophisticated strategies to guide procedural planning. The contemporary procedural success rate is 80-90% with a reduction in complications. Although there has been no improvement in prognosis in randomised trials to date, they, and other controlled registries of thousands of patients, confirm the pivotal role of CTO recanalisation in the treatment of angina and dyspnoea and an improvement in quality of life. Despite this evidence, CTO recanalisation is grossly underutilised. This review reports a detailed overview of the history, indications and treatment strategies for CTO recanalisation and hopes to increase interest among new, and especially young, operators in this demanding, rapidly evolving field of interventional cardiology.

Temporal patterns of multi-morbidity in 570157 ischemic heart disease patients: a nationwide cohort study

Background

Patients diagnosed with ischemic heart disease (IHD) are becoming increasingly multi-morbid, and studies designed to analyze the full spectrum are few.

Methods

Disease trajectories, defined as time-ordered series of diagnoses, were used to study the temporality of multi-morbidity. The main data source was The Danish National Patient Register (NPR) comprising 7,179,538 individuals in the period 1994–2018. Patients with a diagnosis code for IHD were included. Relative risks were used to quantify the strength of the association between diagnostic co-occurrences comprised of two diagnoses that were overrepresented in the same patients. Multiple linear regression models were then fitted to test for temporal associations among the diagnostic co-occurrences, termed length two disease trajectories. Length two disease trajectories were then used as basis for constructing disease trajectories of three diagnoses.

Results

In a cohort of 570,157 IHD disease patients, we identified 1447 length two disease trajectories and 4729 significant length three disease trajectories. These included 459 distinct diagnoses. Disease trajectories were dominated by chronic diseases and not by common, acute diseases such as pneumonia. The temporal association of atrial fibrillation (AF) and IHD differed in different IHD subpopulations. We found an association between osteoarthritis (OA) and heart failure (HF) among patients diagnosed with OA, IHD, and then HF only.

Conclusions

The sequence of diagnoses is important in characterization of multi-morbidity in IHD patients as the disease trajectories. The study provides evidence that the timing of AF in IHD marks distinct IHD subpopulations; and secondly that the association between osteoarthritis and heart failure is dependent on IHD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-022-01527-3.

Sex differences in mortality in stable patients undergoing vasodilator stress cardiovascular magnetic resonance

OBJECTIVE

We assessed the influence of the ischaemic burden (IB) as derived from vasodilator stress cardiovascular magnetic resonance (CMR) on the risk of death and the effect of revascularisation across sex.

METHODS

We evaluated 6237 consecutive patients with known or suspected chronic coronary syndrome (CCS). Extensive ischaemia was defined as >5 segments with perfusion deficit. Multivariate Cox proportional hazard regression models were used.

RESULTS

A total of 2371 (38.0%) patients were women and 583 (9.3%) underwent CMR-related revascularisation. During a median follow-up of 5.13 years, 687 (11.0%) deaths were reported. We found an adjusted differential effect of CMR-derived IB across sex (p value for interaction=0.039). Women exhibited an adjusted lower risk of death and only equaled men's risk when extensive ischaemia was present. Likewise, CMR-related revascularisation was shown to be differentially associated with the risk of mortality across sex (p value for interaction=0.025). In patients with non-extensive ischaemia, revascularisation was associated with a higher risk of death, with a greater extent in women. At higher IB, revascularisation was associated with a lower risk in men, with more uncertain results in women.

CONCLUSIONS

CMR-derived IB allows predicting the risk of death and gives insight into the potential effect of revascularisation in men and women with CCS. Compared with men, women with non-extensive ischaemia displayed a lower risk and a similar risk with a higher IB. The impact of CMR-related revascularisation on mortality risk was also significantly different according to IB and sex. Further research will be needed to confirm these hypothesis-generating findings.

The ISCHEMIA trial: Implications for non-invasive imaging

Coronary artery disease (CAD) is highly prevalent and constitutes the single most common cause of death worldwide. However, the diagnosis of CAD remains challenging. There are two ways to approach the diagnosis of CAD, namely (1) by a functional non-invasive stress test to detect ischemia (stress echocardiography, stress cardiovascular magnetic resonance, single-photon emission computed tomography, positron emission tomography) or (2) by imaging for stenosis visualization (coronary computed tomography angiography or invasive coronary angiography). There are also two approaches for treatment: medical treatment and revascularization. The International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) trial investigated the outcome differences of patients who had moderate to severe ischemia on stress testing and who, after CT angiography, had ruled out left main stenosis and demonstrated at least 1 coronary artery stenosis exceeding 50%. The patients were randomized to an initially conservative treatment versus immediate revascularization. No difference in hard outcomes was found, but angina relief was more effective in the revascularization group. In this article, we explore the implications of the ISCHEMIA trial for non-invasive testing in suspected CAD.

The Management of Coronary Artery Disease in Ethiopia: Emphasis on Revascularization

Cardiovascular diseases are number one cause of death worldwide. Over half of the cardiovascular diseases, 51%, are due to coronary artery disease. Coronary artery disease is a pathological process characterized by atherosclerotic plaque accumulation in the epicardial coronary arteries. Rupture of the fibrous cap of the plaque causes the majority of the deaths due to myocardial infarction. Angina pectoris is a discomfort in the chest or adjacent areas caused by myocardial ischemia usually precipitated by exertion. In acute coronary syndrome, the chest discomfort is either of low threshold or appears at rest and when it evolves on the background of established angina pectoris, the discomfort becomes more frequent and prolonged. Exercise electrocardiography which has been the most frequently used non-invasive test to diagnose obstructive coronary artery disease is currently shown to have inferior diagnostic performance compared with diagnostic imaging tests. The pivotal tests in patients presenting with clinical features of acute coronary syndrome are electrocardiography and determination of serum troponin I and/or T. Revascularization is the mainstay of treatment in patients with acute coronary syndrome. In chronic coronary syndrome, on top of optimal medical treatment, revascularization reduces mortality in:- 1) left main stenosis, 2) three-vessel coronary artery disease, particularly with ejection fraction of less than 40%, 3) two vessel disease with more than 75% stenosis of the proximal left anterior descending coronary artery disease.

Long-Term Clinical Outcomes Following Revascularization in High-Risk Coronary Anatomy Patients With Stable Ischemic Heart Disease

Background The ISCHEMIA (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches) trial failed to show a reduction in hard clinical end points with an early invasive strategy in stable ischemic heart disease (SIHD). However, the influence of left main disease and high-risk coronary anatomy was left unaddressed. In a large angiographic disease-based registry, we examined the modulating effect of revascularization on long-term outcomes in anatomically high-risk SIHD. Methods and Results 9016 patients with SIHD with high-risk coronary anatomy (3 vessel disease with ≥70% stenosis in all 3 epicardial vessels or left main disease ≥50% stenosis [isolated or in combination with other disease]) were selected for study from April 1, 2002 to March 31, 2016. The primary composite of all-cause death or myocardial infarction (MI) was compared between revascularization versus conservative management. A total of 5487 (61.0%) patients received revascularization with either coronary artery bypass graft surgery (n=3312) or percutaneous coronary intervention (n=2175), while 3529 (39.0%) patients were managed conservatively. Selection for coronary revascularization was associated with improved all-cause death/MI as well as longer survival compared with selection for conservative management (Inverse Probability Weighted hazard ratio [IPW-HR] 0.62; 95% CI 0.58 to 0.66; P<0.001; IPW-HR 0.57; 95% CI 0.53-0.61; P<0.001, respectively). Similar risk reduction was noted with percutaneous coronary intervention (IPW-HR 0.64, 95% CI 0.59-0.70, P<0.001) and coronary artery bypass graft surgery (IPW-HR 0.61; 95% CI 0.57-0.66; P<0.001). Conclusions Revascularization in patients with SIHD with high-risk coronary anatomy was associated with improved long-term outcome compared with conservative therapy. As such, coronary anatomical profile should be considered when contemplating treatment for SIHD.

External applicability of the ISCHEMIA trial: an analysis of a prospective, nationwide registry of patients with stable coronary artery disease

AIMS

We sought to assess the proportion of patients eligible for the ISCHEMIA trial and to compare the characteristics and outcomes of these patients with those without ISCHEMIA inclusion or with ISCHEMIA exclusion criteria in a contemporary, nationwide cohort of patients with stable coronary artery disease (CAD).

METHODS AND RESULTS

Among the 5,070 consecutive patients enrolled in the START registry, 4,295 (84.7%) did not fulfil the inclusion criteria (ISCHEMIA-Not Included or ISCHEMIA-Unclassifiable), 582 (11.5%) had exclusion criteria (ISCHEMIA-Excluded), and the remaining 193 (3.8%) were classified as ISCHEMIA-Like. At one year, the incidence of the primary outcome, a composite of death from cardiovascular (CV) causes, myocardial infarction (MI), or hospitalisation for unstable angina and heart failure, was 0.5% in the ISCHEMIA-Like versus 3.3% in other patients (p=0.03). The composite secondary outcome of CV mortality and MI occurred in 0.5% of the ISCHEMIA-Like patients and in 1.4% of the remaining patients (p=0.1).

CONCLUSIONS

In a contemporary real-world cohort of stable CAD patients, only 4% resulted in being eligible for the ISCHEMIA trial. These patients presented an extremely low annual risk of adverse events, especially when compared with other groups of stable CAD patients.

[ISCHEMIA trial : Is coronary CT angiography the new gatekeeper?]

BACKGROUND

The ISCHEMIA trial systematically compared two major principles in the therapy of coronary artery disease (CAD): medical therapy versus revascularization in patients with a positive noninvasive test for myocardial ischemia. Specifically, it was designed to answer the question whether in patients with demonstrated ischemia, after ruling out left main stenosis by coronary computed tomography angiography (CTA), a routine interventional strategy in addition to optimal medical therapy would improve clinical outcome over an initial strategy of medical therapy alone.

CONCLUSION

Overall, this hypothesis could not be confirmed. In several ways, the trial yields interesting information in the field of cardiac imaging. First, a positive stress test result was not associated with a prognostic benefit of revascularization. Second, even though the evaluation of coronary CTA was not part of the protocol, the good outcome achieved by using coronary CTA as a "gatekeeper" during randomization supports the potential of coronary CTA as a diagnostic tool-both first- and second-line-when CAD is suspected. However, the trial also raises new questions in the field of cardiac imaging which will need to be addressed in future studies.

International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) trial and the appropriateness of revascularization

The recently published ISCHEMIA trial which is a prospective randomized multi-centre trial has concluded that there was no evidence that an initial invasive strategy of revascularisation in patients with stable angina reduced the risk of ischaemic cardiovascular events or death from any cause. The trial has confirmed that patients with stable angina do not greatly benefit from revascularisation and optimal medical treatment (OMT) is an acceptable alternative. The trial has also confirmed that in patients with stable angina and end-stage renal impairment, OMT is once again an equally effective initial strategy. While the ISCHEMIA trial is one of the most rigorously and meticulously conducted trial, exclusion of symptomatic patients, recruitment of patients who are not known to derive significant benefit from revascularisation and those who were at low risk of clinical events, along with a short follow-up period, may all have contributed to the lack of difference seen between the groups. The fact that the ISCHEMIA trial does not represent the entire cohort of real-life patients requiring revascularisation should be borne in mind, and care should be taken in extrapolating these results to the wider group of patients requiring revascularisation for coronary artery disease.

Applicability and Eligibility of the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) for Patients who Underwent Revascularization with Percutaneous Coronary Intervention

In the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) trial, an early invasive strategy did not decrease mortality compared to a conservative strategy for stable ischemic heart disease (SIHD) patients with moderate-to-severe ischemia, and the role of revascularization would be revised. However, the applicability and potential influence of this trial in daily practice remains unclear. Our objective was to assess the eligibility and representativeness of the ISCHEMIA trial on the patients with percutaneous coronary intervention (PCI). From a multicenter registry, we extracted a consecutive 13,223 SIHD patients with PCI (baseline cohort). We applied ISCHEMIA eligibility criteria and compared the baseline characteristics between the eligible patients and the actual study participants (randomized controlled trial (RCT) patients). In 3463 patients with follow-up information (follow-up cohort), the 2 year composite of major adverse cardiac events was evaluated between the eligible patients and RCT patients, as well as eligible and non-eligible patients in the registry. In the baseline cohort, 77.3% of SIHD patients with moderate-to-severe ischemia were eligible for the ISCHEMIA. They were comparable with RCT patients for baseline characteristics and outcomes unlike the non-eligible patients. In conclusion, the trial results seem applicable for the majority of PCI patients with moderate-to-severe ischemia except for the non-eligible patients.