Myocardial infarction with non-obstructive coronary arteries (MINOCA)

Coronary microcirculation in myocardial ischemia: A genetic perspective

Coronary microvascular dysfunction (CMD) is a major contributor to ischemic heart disease (IHD), acting both independently and together with atherosclerosis. CMD encompasses structural and functional microcirculatory changes that result in dysregulated coronary blood flow. Structural abnormalities include microvascular remodeling, resulting in arteriolar and capillary narrowing, perivascular fibrosis and capillary rarefaction. Endothelial dysfunction and smooth muscle cell hyperactivity further impair microcirculation. Genetic factors may play a crucial role in the pathophysiology of CMD, mainly due to single nucleotide polymorphisms (SNPs) in genes that regulate coronary blood flow and microcirculation structural modifications. This manuscript aims to review the genetic determinants of CMD, with particular focus on ion channels, microRNAs (miRNAs), and proteins involved in the endothelial environment. The improving knowledge about genetic aspects of CMD opens the possibility to have new biomarkers, improving diagnosis and the development of targeted treatments in light of an even more patient-tailored approach.

Ketone Bodies in the Regulation of Myocardial Perfusion in Cardiovascular Disease: Metabolic and Vasodilatory Effects

Ketone bodies (KBs) serve as an alternative energy source for healthy and failing hearts and have important effects on myocardial blood perfusion in both physiological and pathological states. Early animal studies suggest that KBs may provide protective benefits in ischemic heart disease and heart failure. Under normal circumstances, coronary blood flow regulation is an intricate system with contributions from metabolic, autonomic, compressive, and endothelial factors, with the metabolic regulatory pathway being the most significant contributor. We conducted a non-systematic review of studies published between 1987 and 2024. In this review, we explored the physiological autoregulation of normal coronary blood flow, the role of ketone bodies in myocardial perfusion in health and disease, and the potential role of exogenous ketone body supplementation in producing salutary effects on myocardial blood flow (MBF) and metabolism in exercise and cardiac disease states including ischemia, heart failure, and the aging heart. Overall, our findings demonstrated that KBs improve MBF and ejection fraction in healthy human subjects and have beneficial effects on cardiac output and left heart filling pressures in patients with decompensated heart failure. Although resting myocardial blood flow decreases with age, further studies are required to assess the impact of KBs on MBF in aging populations. Additionally, more research is needed to investigate the effects of KBs during exercise and in instances of myocardial ischemia.

Impact of smoking in MINOCA patients

BACKGROUND

Considerable research has been conducted in recent years on patients afflicted with myocardial infarction with nonobstructive coronary disease (MINOCA), focussing on its prognosis, prevalence and predisposing risk factors. Nevertheless, there remains a dearth of information regarding the baseline characteristics and outcomes of MINOCA patients with a history of smoking. This study endeavours to examine the in-hospital complications and baseline characteristics of a presumed MINOCA cohort comprising individuals with a history of smoking.

METHODS

In this study, a total of 373 patients (85 current smokers and 283 non-smokers), who exhibited elevated troponin levels but had no evidence of obstructive coronary artery disease, were enrolled between 2010 and 2021. MINOCA patients had to fulfil the modified criteria for acute myocardial infarction (AMI) based on the 'Fourth Universal Definition of Myocardial Infarction', including an up- or downregulated troponin level with at least one value exceeding the 99th percentile, along with clinical evidence of infarction (e.g. ischaemic ECG changes, myocardial damage or coronary thrombus). Additionally, patients with less than 50% stenosis of a major epicardial vessel without intervention and those with alternative diagnoses mimicking troponin-positive nonobstructive coronary disease were excluded. It should be noted that there were five patients for whom data regarding smoking status were not available. The primary objective of this investigation was to evaluate the occurrence of various in-hospital events, including pulmonary oedema, invasive ventilation, cardiogenic shock, stroke, cardiopulmonary resuscitation, malignant cardiac arrhythmias, supraventricular arrhythmias, left ventricular thrombus, thromboembolic events and in-hospital mortality. Additionally, long-term cardiovascular events were assessed over an 11-year follow-up period.

RESULTS

Baseline demographics in smokers and non-smokers showed notable differences in the prevalence of supraventricular arrhythmia, particularly atrial fibrillation (5.8% vs. 17.4%; p = .020), diabetes mellitus (DM) (10.5% vs. 19.7%; p = .051), kidney disease (9.3% vs. 15.9%; p = .075) and chronic obstructive pulmonary disease (COPD) (18.6% vs. 10.8%; p = .057). The occurrence of in-hospital cardiovascular events and mortality rates was found to be comparable between smokers and non-smokers. However, non-smokers experienced a higher incidence of long-term cardiovascular events compared to smokers. A multivariable Cox analysis for long-term outcomes indicated that individuals under the age of 50 who were smokers had a more favourable outcome. Nonetheless, the presence of DM, supraventricular tachycardia, pulmonary disease and neurological disease were all associated with a diminished long-term prognosis.

CONCLUSION

Although the long-term health outcomes for smokers are comparatively superior to those of non-smokers, this contrast can be attributed to the increased incidence of cardiovascular comorbidities and the older age distribution within the non-smoking population.

State of the Art in Imaging of Acute Coronary Syndrome with Nonobstructed Coronary Arteries

Acute chest pain is a common concern for which patients present to the emergency department. Nonetheless, many patients with acute chest pain indicative of acute coronary syndrome (ACS) show nonobstructed coronary arteries at invasive coronary angiography or coronary CT angiography (CCTA), which is a clinical conundrum in day-to-day practice. Guidelines recommend that the initial course of action for patients experiencing acute chest pain is to exclude extracardiac and cardiac conditions that could cause nonischemic myocardial damage, including aortic dissection, pulmonary embolism, or septic shock. The generic term troponin-positive with nonobstructed coronary arteries (TpNOCA) was coined to refer to patients with nonobstructed coronary arteries who present with clinical symptoms and signs of ACS and increased cardiac troponin levels, electrocardiographic changes, or both. The causes of TpNOCA may be ischemic (eg, myocardial infarction with nonobstructed coronary arteries [MINOCA] or ischemia with nonobstructed coronary arteries [INOCA]) or nonischemic (eg, extracardiac and cardiac entities). MINOCA and INOCA are working diagnostic terms used until a definitive cause is established (eg, coronary plaque rupture, coronary artery dissection, or coronary microvascular disease). Noninvasive cardiac imaging techniques, notably CCTA and cardiac MRI, and ischemia testing are pivotal in evaluating and treating these patients through accurate identification of the underlying cause, improvement in risk stratification, and guidance for clinicians in decision making for treatment and follow-up. ©RSNA, 2025.

Impact of Mental Health Disorders in Patients with Myocardial Infarction with Non-obstructive Coronary Arteries: A Propensity Score-Matched Nationwide Analysis

BACKGROUND

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is defined by myocardial infarction criteria with < 50% stenosis and no clear cause. While mental health disorders are linked to cardiovascular risk, their impact on MINOCA outcomes is not well studied.

METHODS

We conducted a retrospective cohort study using the National Inpatient Sample (NIS) from 2017 to 2021, identifying hospitalized MINOCA patients with and without mental health disorders using ICD-10-CM codes. Propensity score matching and inverse probability weighting (IPW) were employed to adjust for confounders and balance baseline characteristics. Multivariable logistic regression estimated adjusted odds ratios and 95% confidence intervals for in-hospital outcomes.

RESULTS

Among 4300 propensity-matched pairs (8600 patients), MINOCA patients with mental health disorders had higher in-hospital mortality (2.26% vs 1.21%, p < 0.001) and increased risk of sudden cardiac arrest (1.51% vs 0.65%, p < 0.001). They were also more likely to develop pulmonary embolism (1.54% vs 0.65%, p < 0.001) and acute kidney injury (25.45% vs 20.24%, p < 0.001).

CONCLUSION

Mental health disorders are independently associated with higher in-hospital mortality and adverse cardiovascular outcomes among MINOCA patients. These findings highlight the urgent need for integrated cardiovascular and psychiatric care, emphasizing early screening, multidisciplinary management, and targeted interventions to improve patient outcomes.

Dual Antiplatelet Therapy and Clinical Outcomes in Patients With Myocardial Infarction With Nonobstructive Coronary Arteries: A Systematic Review and Meta-Analysis

Myocardial infarction with nonobstructive coronary arteries (MINOCA) represents a clinical challenge due to its diverse etiologies and uncertain prognosis. Dual antiplatelet therapy (DAPT) is a cornerstone of secondary prevention in traditional myocardial infarction, but its role in MINOCA remains unclear. The purpose of this review was to systematically search the literature and perform a meta-analysis on the effect of DAPT for secondary prevention in patients with MINOCA. A systematic search was conducted in PubMed and Cochrane Central Register of Controlled Trials (CENTRAL) up to June 2024. Cohort studies involving MINOCA patients treated with DAPT and reporting major adverse cardiovascular events (MACE) during follow-up were included. Meta-analysis was conducted using DerSimonian and Laird random-effects model. Seven studies with 12,307 MINOCA patients were included. Meta-analysis showed a trend toward a lower risk of MACE in patients receiving DAPT (pooled hazard ratio: 0.82, 95% confidence interval: 0.66-1.03); however, the results were not statistically significant. DAPT may reduce the risk of MACE in MINOCA patients, but the evidence is not conclusive. Further trials are needed to confirm these findings.

The under-representation of women in cardiovascular clinical trials: State-of-the-art review and ethical considerations

This review describes and evaluates the representation of women in cardiovascular randomized controlled trials (RCT), it reports significant under-representation of women in clinical trials both as participants and researchers and discusses the ethical implications of under-representation. The under-representation of women as participants in cardiovascular RCTs is evident in trials investigating cardiovascular drugs, acute coronary syndrome, heart failure and interventional procedures and devices. Under-representation of women is also evident in the authorship of cardiovascular clinical trials and in trial leadership roles, and under-representation of women as trial investigators is independently associated with under- recruitment of women as trial participants. A notable lack of RCTs investigating conditions that disproportionately affect women is also evident, this triad of underrepresentation for women as participants, and investigators, and the lack of RCTs into conditions predominantly experienced by women, all contribute to the gender gap in cardiovascular outcomes. Better representation of women in clinical trials, in trial leadership and authorship is a key factor to address to equity, distributive justice and improve outcomes for women with cardiovascular disease.

Myocardial infarction with nonobstructive coronary arteries: A clinical review

ABSTRACT

Myocardial infarction with nonobstructive coronary arteries (MINOCA) is an important, often underrecognized working diagnosis. MINOCA is defined as an acute MI in a patient whose coronary angiography reveals no significant obstructive coronary artery disease. A comprehensive diagnostic approach beyond the initial coronary angiogram is essential for identifying this heterogeneous infarction pathophysiology. Distinguishing disease-specific causes affects patient management and prognosis, especially in female patients. This article provides an evidence-based overview of the tailored management strategies and ongoing clinical research likely to shape future guidelines.

Differences between MINOCA and type 2 myocardial infarction: An ITALIAN observational study

BACKGROUND

Myocardial infarction with non-obstructive coronary arteries (MINOCA) and type 2 myocardial infarction (MI), both presenting as non-ST-elevation MI (NSTEMI), are often grouped together due to overlapping symptoms. The aim of our study is to compare their characteristics and prognosis to distinguish between them.

METHODS

Among 7815 patients with NSTEMI who underwent coronary angiography between 2005 and 2022 we identified 538 patients with diagnosis of MINOCA (n = 301; 3,9 %) and type 2 MI (n = 237; 3 %). The outcome was a composite of all-cause mortality, non-fatal MI, hospitalisation for heart failure (HF) and transitory ischemic attack or non-fatal stroke.

RESULTS

The mean age of the entire cohort was 68 (11.5) years, with women being the most frequently represented group (65 %). Comparing the sub-cohorts, MINOCA patients were younger (66.3 (11.7) Vs. 70.6 (11) years, p < 0.01), and less likely to have typical cardiovascular risk than type 2 MI patients. At multivariable analysis different clinical (age, heart rate, typical chest pain, palpitations, postmenopausal status), and instrumental (cardiac rhythm, ST-segment changes, diastolic dysfunction, hypo/akinesia with non-coronary distribution) variables were independent predictors of MINOCA with AUC of 0.83 [95 % CI, 0.78-0.88], p < 0.01 at ROC analysis. At a median follow-up of 61 (IQR 34-100) months, MINOCA patients had significantly lower rate of the composite endpoint compared to type 2 MI (20 % Vs. 32 %, p < 0.01).

CONCLUSIONS

MINOCA cohort was associated with different characteristics compared to type 2 MI and had a better prognosis despite the number of events was not negligible.

Sex differences in patients with working diagnosis of myocardial infarction with nonobstructive coronary arteries (MINOCA)

Myocardial infarction with nonobstructive coronary arteries (MINOCA) constitutes 3-15% of all acute myocardial infarctions. Women are more frequently diagnosed with MINOCA, although the influence of sex on long-term outcomes is still unclear. In this study we aimed to compare sex-based differences in baseline characteristics and clinical outcomes in patients with suspected MINOCA. We have retrospectively analyzed 6063 patients diagnosed with MINOCA (3220 females and 2843 male patients) from combined 3 large polish registries (PL-ACS, SILCARD and AMI-PL). Male patients were significantly younger (63 (55-74) vs. 71 (61-79) years, p < 0.05) and less frequently diabetic (20.1% vs. 24.1%, p < 0.05). Mortality was significantly higher in male population (11.8% vs. 10.2%, p < 0.05 at 1 year and 17.6% vs. 15.0%, p < 0.05 at 3 years). Male sex was an independent predictor of both mortality (HR = 1.29; CI 1.11-1.51; p < 0.05) and myocardial infarction (HR = 1.39; CI 1.1-1.75, p < 0.05) at 3 years follow-up. All-cause readmission rates were similar in male and female patients both at 1 year (46.0% vs. 44.4, p = 0.2) and 3 years follow-up (56.4% vs. 56.5%, p = 0.93). However, cardiovascular readmissions were more prevalent in male patients at both timepoints (33.9% vs. 29.10%, p < 0.05 at 1 year, and 41.0% vs. 37.6%, p < 0.05 at 3 years). This large-scale registry-based analysis demonstrated higher 3 years rates of adverse events, including death and MI among male patients with suspected MINOCA.

Artificial Intelligence in Imaging for Personalized Management of Coronary Artery Disease

The precision of imaging and the number of other risk-assessing and diagnostic methods are constantly growing, allowing for the uptake of additional strategies for individualized therapies. Personalized medicine has the potential to deliver more adequate treatment, resulting in better clinical outcomes, based on each patient's vulnerability or genetic makeup. In addition to increased efficiency, costs related to this type of procedure can be significantly lower. Useful assistance in designing individual therapies may be assured by the adoption of artificial intelligence (AI). Recent years have brought essential developments in deep and machine learning techniques. Advances in technologies such as convolutional neural networks (CNNs) have enabled automatic analyses of images, numerical data, and video data, providing high efficiency in the creation of prediction models. The number of AI applications in medicine is constantly growing, and the effectiveness of these techniques has been demonstrated in coronary computed tomography angiography (CCTA), optical coherence tomography (OCT), and many others. Moreover, AI models may be useful in direct therapy optimization for patients with coronary artery disease (CAD), who are burdened with high risk. The combination of well-trained AI with the design of individual treatment pathways can lead to improvements in health care. However, existing limitations, such as non-adapted guidelines or the lack of randomized clinical trials to evaluate AI's true accuracy, may contribute to delays in introducing automatic methods into practical use. This review critically appraises the developed tools that are potentially useful for clinicians in guiding personalized patient management, as well as current trials in this field.

Hypertensive Crisis and Myocardial Infarction With Non-obstructive Coronary Arteries in a Leprosy Patient With Erythema Nodosum Leprosum: The Role of Corticosteroids

A hypertensive crisis is a severe condition characterized by a sudden, critical rise in blood pressure, which can lead to organ damage. Myocardial infarction occurring in the absence of significant coronary artery stenosis is referred to as myocardial infarction with non-obstructive coronary arteries (MINOCA). Patients with leprosy may develop erythema nodosum leprosum (ENL), a serious inflammatory condition that can impair cardiovascular health and is frequently treated with corticosteroids. In this case, we describe a 52-year-old male patient, known to have hypertension, who complained of breathlessness, facial edema, and chest pain. Additional testing indicated hypertension, elevated cardiac biomarkers, and an ECG that showed characteristics of a non-ST segment elevation myocardial infarction (NSTEMI). When coronary angiography was performed, non-obstructive epicardial coronary arteries were discovered.

Sex differences in myocardial infarction care and outcomes: a longitudinal Scottish National Data-Linkage Study

AIMS

We investigate sex disparities in management and outcomes of myocardial infarction (MI) in contemporary practice in Scotland.

METHODS AND RESULTS

This was a longitudinal cohort study including all MI admissions aged 45-80 years across Scotland between 2010-2016 and 2:1 age, sex, and general practice-matched general population controls. Participants were followed up until the end of 2021. We analysed in-hospital outcomes (percutaneous coronary intervention, secondary prevention and mortality) using Poisson regressions, adjusting for age, comorbidities, and ST-elevation. We used Royston-Parmar models for long-term outcomes (all-cause and cardiovascular mortality, incident cardiovascular events), adjusting for age, comorbidities, and secondary prevention. Of a total 47 063 MI patients, 15 776 (33.5%) were women. Median (inter-quartile range) age was 66 (57, 73) years. Compared to men, women were older and more comorbid, but were less likely to undergo percutaneous coronary intervention [risk ratio (95% confidence interval) - 0.87 (0.86 - 0.89)] or receive secondary prevention at discharge [0.94 (0.93-0.95)]. No in-hospital mortality difference was observed between sexes [1.06 (0.99-1.13) after adjustment]. Over a median follow-up of 8.2 (6.7, 10.1) years, women had higher crude rates of adverse outcomes. After full adjustment, this translated into a lower risk for women compared to men of all-cause mortality [hazard ratio, 0.92 (0.89-0.95)], cardiovascular mortality [0.82 (0.78-0.87)], and cardiovascular events [0.92 (0.88-0.95)]. The female survival advantage seen in general population controls was attenuated in MI patients.

CONCLUSION

Women were undertreated compared to men after MI. Their survival and outcome benefits may be improved further. Poor outcomes in men despite better receipt of secondary prevention require further attention.

Unusual Recurrent Multivessel Coronary Artery Spasm: A Case Report and Literature Review

Coronary artery spasms (CAS) can manifest in various forms, from silent ischemia to severe cardiac events like myocardial infarction and sudden death. This case involves a 56-year-old male with recurrent ischemic chest pain and varying ECG signs. Cardiac catheterization revealed multiple coronary spasms that resolved spontaneously or with intracoronary nitroglycerin. The report emphasizes the severe presentations of multiple CAS and the importance of thorough diagnostic evaluation to avoid unnecessary interventions, highlighting the diagnostic challenges in managing such cases.

Takotsubo Syndrome: An International Expert Consensus Report on Practical Challenges and Specific Conditions (Part-1: Diagnostic and Therapeutic Challenges)

In the recent years, there has been a burgeoning interest in Takotsubo syndrome (TTS), which is renowned as a specific form of reversible myocardial dysfunction. Despite the extensive literature available on TTS, clinicians still face several practical challenges associated with the diagnosis and management of this phenomenon. This potentially results in the underdiagnosis and improper management of TTS in clinical practice. The present paper, the first part (part-1) of the consensus report, aims to cover diagnostic and therapeutic challenges associated with TTS along with certain recommendations to combat these challenges.

One-Year Prognosis Difference of Myocardial Infarction With or Without Coronary Obstruction in Developing Countries: Insights From the Moroccan Experience

Introduction

The debate remains open as to the difference in prevalence of mortality and occurrence of acute events in patients with Myocardial infarction with non-obstructive coronary arteries (MINOCA) and others with Myocardial infarction with coronary arteries disease (MI-CAD).

Methods

We conducted a 2-year retrospective study for patients admitted for Acute coronary syndrome (ACS) to analyze the clinical and prognostic characteristics of patients with MINOCA versus MI-CAD. We defined 1-year all-cause mortality as the primary outcome, and the secondary outcome as a composite of 1-year readmission for myocardial infarction or acute heart failure (AHF).

Results

Our study included 1077 patients, 95.3% with MI-CAD and 4.7% with MINOCA. At admission, 71.1% patient were diagnosed STEMI and 28.9% with NSTEMI. The difference between the 2 groups was found on age (P < .001), hypertension, diabetes with consecutive P-values of .007 and .001, as well as Ejection fraction (P < .001). For the outcomes studied, the difference was significant between the 2 groups for all events, and MINOCA patients had a better prognosis than MI-CAD patients, with adjusted hazard ratios (HR) for 1-year mortality (HR = 0.601 P = .004), for readmission for ACS (HR = 0.662; P = .002) and for readmission for AHF (HR = 0.539; P = .019).

Conclusion

Despite the ambiguity in the genesis of MINOCA, the short- and long-term prognosis of these patients remains generally favorable.

Myocardial infarction with non-obstructive coronary arteries in a young seropositive woman with human immunodeficiency virus: a case report and review of the literature

BACKGROUND

Elevated susceptibility to acute myocardial infarction and various cardiovascular diseases has been observed in individuals infected with the human immunodeficiency virus compared with the uninfected population, as demonstrated in numerous studies. The precise mechanism by which human immunodeficiency virus infection heightens the risk of acute myocardial infarction remains elusive. The manifestation of acute coronary syndrome in young patients with human immunodeficiency virus may deviate from the typical, displaying distinct pathophysiological and clinical characteristics. The occurrence of myocardial infarction with non-obstructive coronary arteries in young patients with human immunodeficiency virus poses diagnostic and treatment challenges.

CASE PRESENTATION

We present the case of a 46-year-old African woman with no traditional atherosclerotic risk factors. She was diagnosed with human immunodeficiency virus-1 infection 2 years prior to her current admission for chest pain. Her troponin levels were elevated, suggestive of acute coronary syndrome. Although coronary angiography ruled out coronary artery stenosis, it revealed mild myocardial bridging in the left anterior descending artery. Cardiac magnetic resonance imaging confirmed myocardial infarction, indicating a myocardial infarction with non-obstructive coronary arteries with an apical thrombus in the left ventricle. Following medical treatment, the patient experienced resolution of chest pain and improvement in ST-segment elevation.

CONCLUSIONS

In young female patients without traditional risk factors, human immunodeficiency virus infection is a possible etiological factor for myocardial infarction with non-obstructive coronary arteries. The likely pathophysiological pathway is superficial endothelial cell denudation as a result of chronic inflammation and immune activation.

Spectrum of Non-Obstructive Coronary Artery Disease and Its Relationship with Atrial Fibrillation

This article aims to analyze the relationship between non-obstructive coronary artery disease (NOCAD) and atrial fibrillation (AF), exploring the underlying pathophysiological mechanisms and implications for clinical management. NOCAD and AF are prevalent cardiovascular conditions that often coexist, yet their interrelation is not well understood. NOCAD can lead to ischemic necrosis of cardiomyocytes and their replacement with fibrous tissue, sustaining focal ectopic activity in atrial myocardium. Atrial fibrillation, on the other hand, the most common sustained cardiac arrhythmia, is able to accelerate atherosclerosis and increase oxygen consumption in the myocardium, creating a mismatch between supply and demand, and thus promoting the development or worsening of coronary ischemia. Therefore, NOCAD and AF seem to be a complex interplay with one begets another.

Myocardial Infarction With Non-obstructive Coronary Arteries (MINOCA): A Case Report and Comprehensive Discussion of Pathophysiology and Risk Factors

Myocardial infarction with non-obstructive coronary arteries (MINOCA) refers to the occurrence of myocardial infarction symptoms and signs despite angiographic findings showing normal or near-normal coronary arteries. Unlike the more commonly recognized myocardial infarction with coronary artery disease (MICAD), MINOCA often has a better prognosis; however, it is not without risk, as it is associated with increased mortality. We present a 72-year-old female who presented to the hospital with acute chest pain. Following a thorough diagnostic workup, including laboratory tests, left heart catheterization, and cardiac imaging, she was diagnosed with MINOCA. This case report provides a comprehensive review of the pathophysiological mechanisms underlying MINOCA, such as plaque disruption without significant stenosis, microvascular dysfunction, coronary artery spasm, coronary thrombosis or embolism, and spontaneous coronary artery dissection. Additionally, we explore the associated risk factors, highlighting the unconventional risk factors. MINOCA represents a diverse clinical condition with various causes and complex pathophysiology. The variability underscores the necessity for further research to deepen our understanding of this condition. Enhanced knowledge will lead to better diagnostic and treatment strategies, ultimately improving patient outcomes.

Transient Left Ventricular Dysfunction from Cardiomyopathies to Myocardial Viability: When and Why Cardiac Function Recovers

Transient left ventricular dysfunction (TLVD), a temporary condition marked by reversible impairment of ventricular function, remains an underdiagnosed yet significant contributor to morbidity and mortality in clinical practice. Unlike the well-explored atherosclerotic disease of the epicardial coronary arteries, the diverse etiologies of TLVD require greater attention for proper diagnosis and management. The spectrum of disorders associated with TLVD includes stress-induced cardiomyopathy, central nervous system injuries, histaminergic syndromes, various inflammatory diseases, pregnancy-related conditions, and genetically determined syndromes. Furthermore, myocardial infarction with non-obstructive coronary arteries (MINOCA) origins such as coronary artery spasm, coronary thromboembolism, and spontaneous coronary artery dissection (SCAD) may also manifest as TLVD, eventually showing recovery. This review highlights the range of ischemic and non-ischemic clinical situations that lead to TLVD, gathering conditions like Tako-Tsubo Syndrome (TTS), Kounis syndrome (KS), Myocarditis, Peripartum Cardiomyopathy (PPCM), and Tachycardia-induced cardiomyopathy (TIC). Differentiation amongst these causes is crucial, as they involve distinct clinical, instrumental, and genetic predictors that bode different outcomes and recovery potential for left ventricular function. The purpose of this review is to improve everyday clinical approaches to treating these diseases by providing an extensive survey of conditions linked with TLVD and the elements impacting prognosis and outcomes.

Nonobstructive epicardial coronary artery disease: an evolving concept in need of diagnostic and therapeutic guidance

For decades, we have been treating patients presenting with angina and concerning electrocardiographic changes indicative of ischemia or injury, in whom no culprit epicardial coronary stenosis was found during diagnostic coronary angiography. Unfortunately, the clinical outcomes of these patients were not better than those with recognized obstructive coronary disease. Improvements in technology have allowed us to better characterize these patients. Consequently, an increasing number of patients with ischemia and no obstructive coronary artery disease (INOCA) or myocardial infarction in the absence of coronary artery disease (MINOCA) have now gained formal recognition and are more commonly encountered in clinical practice. Although both entities might share functional similarities at their core, they pose significant diagnostic and therapeutic challenges. Unless we become more proficient in identifying these patients, particularly those at higher risk, morbidity and mortality outcomes will not improve. Though this field remains in constant flux, data continue to become available. Therefore, we thought it would be useful to highlight important milestones that have been recognized so we can all learn about these clinical entities. Despite all the progress made regarding INOCA and MINOCA, many important knowledge gaps continue to exist. For the time being, prompt identification and early diagnosis remain crucial in managing these patients. Even though we are still not clear whether intensive medical therapy alters clinical outcomes, we remain vigilant and wait for more data.

Prognostic factors of MINOCA and their possible mechanisms

OBJECTIVE

Despite not showing substantial stenosis of coronary arteries, Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA) presents with myocardial ischemia injury, thus having a grave prognosis and a high risk of long-term complications. This necessitates increased clinical attention and exploration of its root causes to prevent a similar crisis.

METHODS

Research on MINOCA is limited, especially in terms of its clinical attributes, long-term outlook, risk stratification, and prognosis-linked cardiometabolic risk factors. This review aims to fill these gaps, providing an extensive overview of clinical trials and studies on MINOCA to separate the issue from the presence of non-obstructive coronary arteries in cardiac patients.

RESULTS

It has been found that MINOCA patients still face a high risk of long-term adverse events. Due to social and physiological factors, the hospital mortality rate is higher among women, and they are also more susceptible to MINOCA. Cardiac metabolic risk factors, including disorder of glucose and lipid metabolism, as well as changes in serum CysC levels, have significant impacts on the occurrence and prognosis of MINOCA.

CONCLUSIONS

Further research is still needed to fully understand the complex biological mechanisms underlying the prognostic factors of MINOCA. A profound understanding of these factors could reveal potential targets for improving prognosis, thereby indicating new strategies for managing this cardiovascular condition.

Mortality in ST-Segment Elevation Myocardial Infarction With Nonobstructive Coronary Arteries and Mimickers

Importance

The clinical characteristics and prognosis of patients with ST-segment elevation myocardial infarction (STEMI) with nonobstructive coronaries (MINOCA) are largely unknown.

Objective

To assess differences in 5-year mortality in patients presenting with STEMI due to MINOCA and MINOCA mimickers as compared with obstructive disease.

Design, Setting, and Participants

A retrospective analysis of a prospective registry-based cohort study of consecutive STEMI activations at 3 regional Midwest STEMI programs. STEMI without a culprit artery and elevated troponin levels were categorized as MINOCA (absence of coronary artery stenosis >50% and confirmed or suspected coronary artery plaque disruption, epicardial coronary spasm, or coronary embolism/thrombosis) or MINOCA mimickers (takotsubo cardiomyopathy, myocarditis, or nonischemic cardiomyopathy). Data were analyzed from March 2003 to December 2020.

Main Outcomes and Measures

Adjusted Cox regression analysis was used to assess 5-year mortality risk in STEMI presenting with MINOCA and MINOCA mimickers in comparison with obstructive disease.

Results

Among 8560 consecutive patients with STEMI, mean (SD) age was 62 (14) years, 30% were female (2609 participants), and 94% were non-Hispanic White (4358 participants). The cohort included 8151 patients with STEMI due to obstructive disease (95.2%), 120 patients with MINOCA (1.4%), and 289 patients with MINOCA mimickers (3.8%). Patients were followed up for a median (IQR) of 7.1 (3.6-10.7) years. Patients with MINOCA and MINOCA mimickers were less likely to be discharged with cardiac medications compared with obstructive disease. At 5-year follow-up, mortality in STEMI presenting with obstructive disease (1228 participants [16%]) was similar to MINOCA (20 participants [18%]; χ21 = 1.1; log-rank P = .29) and MINOCA mimickers (52 participants [18%]; χ21 = 2.3; log-rank P = .13). In adjusted Cox regression analysis compared with obstructive disease, the 5-year mortality hazard risk was 1.93 times higher in MINOCA (95% CI, 1.06-3.53) and similar in MINOCA mimickers (HR, 1.08; 95% CI, 0.79-1.49).

Conclusions and Relevance

In this large multicenter cohort study of consecutive clinical patients with STEMI, presenting with MINOCA was associated with a higher risk of mortality than obstructive disease; the risk of mortality was similar in patients with MINOCA mimickers and obstructive disease. Further investigation is necessary to understand the pathophysiologic mechanisms involved in this high-risk STEMI population.

A case report and literature review: pheochromocytoma-mediated takotsubo cardiomyopathy, which is similar to acute myocardial infarction

A 52-year-old Chinese woman was admitted to a cardiac intensive care unit (CCU) due to nausea, vomiting, and dyspnea, which began a day before her hospitalization. Metoprolol succinate and conventional treatment for acute myocardial infarction (AMI) were initially administered to the patient based on electrocardiogram (ECG) findings and elevated cardiac troponin I (cTnI). However, the following day, she developed aggravated nausea, vomiting, fever, sweating, a flushed face, a rapid heart rate, and a significant rise in blood pressure. Furthermore, ultrasonic cardiography (UCG) displayed takotsubo-like changes; nevertheless, ECG indicated inconsistent cTnI peaks with extensive infarction. After coronary computed tomography angiography (CTA) ruled out (AMI), and in conjunction with the uncommon findings, we strongly suspected that the patient had a secondary condition of pheochromocytoma-induced takotsubo cardiomyopathy (Pheo-TCM). In the meanwhile, the use of metoprolol succinate was promptly discontinued. This hypothesis was further supported by the subsequent plasma elevation of multiple catecholamines and contrast-enhanced computed tomography (CECT). After one month of treatment with high-dose Phenoxybenzamine in combination with metoprolol succinate, the patient met the criteria for surgical excision and successfully underwent the procedure. This case report demonstrated that pheochromocytoma could induce TCM and emphasized the significance of distinguishing it from AMI (in the context of beta-blocker usage and anticoagulant management).

Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA): Focus on Coronary Microvascular Dysfunction and Genetic Susceptibility

Among the most common causes of death worldwide, ischemic heart disease (IHD) is recognized to rank first. Even if atherosclerotic disease of the epicardial arteries is known as the leading cause of IHD, the presence of myocardial infarction with non-obstructive coronary artery disease (MINOCA) is increasingly recognized. Notwithstanding the increasing interest, MINOCA remains a puzzling clinical entity that can be classified by distinguishing different underlying mechanisms, which can be divided into atherosclerotic and non-atherosclerotic. In particular, coronary microvascular dysfunction (CMD), classifiable in non-atherosclerotic mechanisms, is a leading factor for the pathophysiology and prognosis of patients with MINOCA. Genetic susceptibility may have a role in primum movens in CMD. However, few results have been obtained for understanding the genetic mechanisms underlying CMD. Future studies are essential in order to find a deeper understanding of the role of multiple genetic variants in the genesis of microcirculation dysfunction. Progress in research would allow early identification of high-risk patients and the development of pharmacological, patient-tailored strategies. The aim of this review is to revise the pathophysiology and underlying mechanisms of MINOCA, focusing on CMD and actual knowledge about genetic predisposition to it.

Coeliac Disease: A Rare Cause of Myocardial Infarction With Non-Obstructive Coronary Arteries

Myocardial infarction with non-obstructive coronary arteries (MINOCA) poses a diagnostic dilemma. Identifying the underlying etiology is essential to ensuring appropriate management. Cardiac magnetic resonance (CMR) is a valuable tool that can aid clinicians for that purpose. Coeliac disease (CD) is characterized by hypercoagulability and a thrombotic state and represents an exceptional cause of MINOCA. We report the case of a 28-year-old woman who presented with chest pain. The diagnosis of non-ST-elevation MI was obtained based on ECG abnormalities and elevated troponin levels. Coronary angiography was normal. CMR showed late gadolinium enhancement in the lateral left ventricular wall, confirming the diagnosis of MINOCA. A duodenal biopsy allowed the diagnosis of CD. Anticoagulation and a gluten-free diet proved beneficial, with a good outcome after a five-year follow-up. This case highlights the essential role of CMR in MINOCA investigations and the importance of thorough etiological assessment in young patients with no cardiovascular risk factors.

Predictors of Long-Term Mortality in Patients with Stable Angina Pectoris and Coronary Slow Flow

Background and Objectives: Coronary slow flow (CSF) is an angiographic phenomenon characterized by the slow progression of an injected contrast agent during diagnostic coronary angiography in the absence of significant stenosis. Although CSF is a common angiographic finding, the long-term outcomes and mortality rates are still unknown. This study aimed to investigate the underlying causes of mortality over a 10-year period in patients diagnosed with stable angina pectoris (SAP) and CSF. Materials and Methods: This study included patients with SAP who underwent coronary angiography from 1 January 2012 to 31 December 2012. All patients displayed CSF despite having angiographically normal coronary arteries. Hypertension (HT), diabetes mellitus (DM), hyperlipidaemia, medication compliance, comorbidities, and laboratory data were recorded at the time of angiography. Thrombolysis in myocardial infarction (TIMI) frame count (TFC) was calculated for each patient. The cardiovascular (CV) and non-CV causes of long-term mortality were assessed. Results: A total of 137 patients with CSF (93 males; mean age: 52.2 ± 9.36 years) were included in this study. Twenty-one patients (15.3%) died within 10 years of follow-up. Nine (7.2%) and 12 (9.4%) patients died of non-CV and CV causes, respectively. Total mortality in patients with CSF was associated with age, HT, discontinuation of medications, and high-density lipoprotein cholesterol (HDL-C) levels. The mean TFC was associated with CV mortality. Conclusion: Patients with CSF exhibited a notable increase in cardiovascular-related and overall mortality rates after 10 years of follow-up. HT, discontinuation of medications, HDL-C levels, and mean TFC were associated with mortality in patients with CSF.