Myocardial Infarction with Nonobstructive Coronary Arteries.

Myocardial infarction with nonobstructive coronary arteries (MINOCA) is an important subtype of myocardial infarction (MI) that occurs in approximately 6-8% of patients with spontaneous MI who are referred for coronary angiography. MINOCA disproportionately affects women, but men are also affected. Pathogenesis is more variable than in MI with obstructive coronary artery disease (MI-CAD). Dominant mechanisms include atherosclerosis, thrombosis, and coronary artery spasm. Management of MINOCA varies based on the underlying mechanism of infarction. Therefore, systematic approaches to diagnosis are recommended. The combination of invasive coronary angiography, multivessel intracoronary imaging, provocative testing for coronary spasm, and cardiac magnetic resonance imaging provides the greatest diagnostic yield. Current clinical practice guidelines for the secondary prevention of MI are based largely on data from patients with MI-CAD. Thus, optimal medications after MINOCA are uncertain. Clinical trials focused on the treatment of patients with MINOCA are urgently needed to define optimal care.

Continuous thermodilution and microvascular resistance reserve during the index procedure in acute coronary syndrome without obstructive coronary artery disease: A pilot study.

BACKGROUND: In 5%-25% of non-ST-elevation acute coronary syndrome (NSTE-ACS) patients, coronary angiography reveals no obstructive coronary arteries (MINOCA). Coronary microvascular disease (CMD) is a potential causal pathophysiological mechanism in these patients and can be diagnosed by continuous thermodilution assessment. Recently, the microvascular resistance reserve (MRR) has been introduced as a novel index to assess the vasodilatory capacity of the microcirculation. However, continuous thermodilution and MRR have never been investigated in the acute setting in MINOCA patients and invasive assessment of the microcirculation in these patients are currently lacking. AIMS: The objectives of the study were to investigate the incidence of CMD (MRR ≤ 2.7) in patients with MINOCA and to evaluate the feasibility and safety of continuous thermodilution-based assessment during index coronary angiography in the acute setting. METHODS: This study was a prospective, observational, pilot study investigating coronary physiology in the acute setting in MINOCA patients. Patients admitted with a diagnosis of NSTE-ACS were eligible for inclusion. RESULTS: In total, 19 MINOCA patients were included in this analysis; the mean age was 70 ± 9 years, and 79% were females. CMD was present in 6 patients (32%). Qrest was significantly higher in the MRR ≤ 2.7 group compared to the MRR > 2.7 group (0.076 [0.057-0.100] vs. 0.049 [0.044-0.071] L/min, p = 0.03). Rµ,rest was significantly lower in the MRR ≤ 2.7 group compared to the MRR > 2.7 group (1083 [710-1510] vs. 1563 [1298-1970] WU, p = 0.04). No periprocedural complications or hemodynamic instability have occurred during continuous thermodilution assessment during the index coronary angiography. CONCLUSION: In patients admitted for MINOCA undergoing immediate coronary angiography, continuous thermodilution assessment and MRR are feasible and safe in the acute setting, and evidence of functional CMD could be observed in one-third of the MINOCA patients.

Value of a short non-contrast CMR protocol in MINOCA.

OBJECTIVES: To evaluate the diagnostic performance of a short non-contrast CMR (ShtCMR) protocol relative to a matched standard comprehensive CMR (StdCMR) protocol in patients with myocardial infarction with non-obstructive coronary arteries (MINOCA). METHODS: This multicenter retrospective study included patients with a working diagnosis of MINOCA who underwent a StdCMR between January 2019 and December 2020. An expert and a non-expert reader performed a blinded reading with the ShtCMR (long-axis cine images, T2w-STIR, T1- and T2-mapping). A consensus reading of the StdCMR (reference standard) was performed at least 3 months after the ShtCMR reading session. Readers were asked to report the following: (1) diagnosis; (2) level of confidence in their diagnosis with the ShtCMR; (3) number of myocardial segments involved, and (4) functional parameters. RESULTS: A total of 179 patients were enrolled. The ShtCMR lasted 21 ± 9 min and the StdCMR 45 ± 11 min (p < 0.0001). ShtCMR allowed reaching the same diagnosis as StdCMR in 85% of patients when interpreted by expert readers (rising from 66% for poor confidence to 99% for good, p = 0.0001) and in 73% (p = 0.01) by non-expert ones (60% for poor vs 89% for good confidence, p = 0.0001). Overall, the ShtCMR overestimated the ejection fraction, underestimated cardiac volumes (p < 0.01), and underestimated the number of segments involved by pathology (p = 0.0008) when compared with the StdCMR. CONCLUSION: The ShtCMR was found to be a debatable alternative to the StdCMR in patients with MINOCA. Nevertheless, when an experienced reader reaches a good or very good diagnostic confidence using the ShtCMR, the reader may choose to stop the examination, reducing the length of the CMR without affecting the patient's diagnosis. CLINICAL RELEVANCE STATEMENT: A short non-contrast CMR protocol may be a viable alternative to standard protocols in selected CMR studies of patients with MINOCA, allowing for faster diagnosis while reducing time and resources and increasing the number of patients who can be scanned. KEY POINTS: • The ShtCMR lasted 21 ± 9 min and the StdCMR 45 ± 11 min (p < 0.0001). • In 57% of patients with MINOCA, the experienced reader considers that contrast medium is probably not necessary for diagnosis without affecting the patient's diagnosis (99% of agreement rate between ShtCMR and StdCMR).

Pharmacotherapy and cardiovascular challenges: a case report of olverembatinib-induced myocardial infarction with non-obstructive coronary arteries.

The anticancer drug of tyrosine kinase-inhibitors (TKIs) has significantly improved the prognosis of patients with specific leukemia but has also increased the risk of organ adverse reactions. Herein, we present a case of a patient diagnosed with myeloproliferative neoplasms who experienced recurrent chest pain after receiving treatment with Olverembatinib. Electrocardiography and coronary angiography confirmed the diagnosis of myocardial infarction with non-obstructive coronary arteries. This case serves as a reminder for clinicians to pay more attention and actively prevent the cardiac adverse reactions of TKIs when using such medications.

Long term all-cause mortality after myocardial infarction with non-obstructed vs obstructed coronary artery disease: a meta-analysis of adjusted data.

BACKGROUND: The difference in the long-term outcomes of myocardial infarction in patients with non-obstructed coronary arteries (MINOCA) and patients with myocardial infarction with obstructed coronary artery disease (MI-CAD) is not clear. The current study aimed to pool adjusted data to compare long-term outcomes of MINOCA vs MI-CAD. METHODS: Electronic literature search of PubMed, Embase, CENTRAL, and Google Scholar databases was done for publications up to 18th June 2023. Only studies reporting multivariable-adjusted data with > 1 year of follow-up were included. RESULTS: Sixteen studies met the inclusion criteria. Our meta-analysis revealed no statistically significant difference in the risk of all-cause mortality between MINOCA and MI-CAD patients (HR: 0.90 95% CI 0.68, 1.19 I2 = 94% p = 0.48). Analysis of the limited data showed a reduced combined risk of all-cause mortality and MI (HR: 0.54 95% CI 0.39, 0.76 I2 = 72% p = 0.003) and major adverse cardiac events (MACE) (HR: 0.66 95% CI 0.51, 0.84 I2 = 51% p = 0.0009) in patients with MINOCA vs MI-CAD, and no difference in the risk of cardiovascular mortality (HR: 0.81 95% CI 0.54, 1.22 I2 = 0% p = 0.31) and readmission between the two groups (HR: 0.85 95% CI 0.61, 1.19 I2 = 90% p = 0.35). CONCLUSION: A pooled analysis of adjusted outcomes from the available studies indicated that MINOCA and MI-CAD patients have similar long-term all-cause mortality risk. Our conclusions on the risk of cardiovascular mortality, MACE and readmission rates need to be taken with caution due to a lack of adequate studies. Further research is needed to strengthen the evidence on this important subject.

Delayed ventricular septal rupture complicated with ventricular aneurysm in a case of myocardial infarction with non-obstructive coronary arteries.

BACKGROUND: Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a rare cause of heart attack, which may not receive sufficient attention from patients during post-discharge treatment, especially among those with normal coronary angiography results. CASE PRESENTATION: We present the case of a 65-year-old woman who was readmitted to the hospital with ventricular septal rupture (VSR) complicated by ventricular aneurysm, occurring 2 weeks after myocardial infarction. During the initial admission, coronary angiography revealed normal coronary arteries, leading to a diagnosis of MINOCA. Epicardial coronary vasospasm or coronary embolism was considered as potential causes; however, the patient did not adhere to standardized treatment upon initial discharge. The delayed VSR led to a decline in cardiac function but did not result in severe hemodynamic impairment. Following correction of heart failure with medications, the patient underwent percutaneous VSR repair 19 days after diagnosis and was discharged with a favorable recovery. CONCLUSIONS: The occurrence of delayed VSR complicated with ventricular aneurysm in patients with MINOCA is rare, highlighting the possibility of serious complications in MINOCA cases. Both cardioprotective therapies and cause-targeted therapies are essential in the management of patients with MINOCA.

Impact of Sex in the Incidence of Heart Failure in Patients with Chronic Coronary Syndrome.

PURPOSE OF REVIEW: This review examines the available evidence concerning the incidence of heart failure in patients with chronic coronary syndrome, with a focus on gender differences. RECENT FINDINGS: The incidence of heart failure in the context of chronic coronary syndrome presents conflicting data. Most of the available information stems from studies involving stable patients' post-acute coronary syndrome, revealing a wide range of incidence rates, from less than 3% to over 20%, observed over 5 years of follow-up. Regarding the gender differences in heart failure incidence, there is no consensus about whether women exhibit a higher incidence, particularly in the presence of evidence of obstructive coronary artery disease. However, in cases where obstructive coronary artery disease is absent, women may face a more unfavourable prognosis due to a higher prevalence of microvascular disease and heart failure with preserved ventricular function. The different profile of ischaemic heart disease in women difficult to establish differences in prognosis independently associated with female sex. Targeted investigations are essential to discern the incidence of heart failure in chronic coronary syndrome and explore potential gender-specific associations.

Spontaneous Coronary Artery Dissection in Clinical Practice: Pathophysiology and Therapeutic Approaches.

Spontaneous coronary artery dissection (SCAD) is a cause of myocardial infarction without obstructive coronary artery disease (MINOCA). It is determined by a coronary artery wall layers separation, which occurs regardless of traumatic or iatrogenic injuries. Even if it is often a missed diagnosis, its incidence is growing along with the improvement of intracoronary imaging techniques that allow for better detection. The main angiographical classification distinguishes three different forms, with slightly different prognoses at long-term follow up. SCAD is a recurrent condition, severely hampering the life quality of affected patients. The predominantly young age of patients with SCAD and the high prevalence of females among them have made the topic increasingly important, especially regarding therapeutic strategies. According to the data, the most recommended treatment is conservative, based on the use of antiplatelet agents and supportive anti-ischemic therapy. However, there are conflicting opinions concerning the need for dual antiplatelet therapy and its duration. In the case of invasive treatment, the choice between percutaneous coronary intervention and coronary artery bypass graft depends on the patient's clinical stability and the interested vessel. The purpose of the current review is to revise the pathophysiological mechanisms underlying SCAD and the current knowledge of its treatment.

Myocardial infarction in a 33-year-old with inflammatory bowel disease: a case report.

BACKGROUND: ST elevation myocardial infarction is defined as acute myocardial injury with necrosis due to myocardial ischemia. The frequent cause is thrombotic occlusion of atherosclerotic coronary arteries. In particular situations, thromboembolism can cause myocardial infarction in patients with normal coronary arteries. CASE PRESENTATION: We report a particular case of myocardial infarction in a young, previously healthy patient with non-atherosclerotic coronary arteries and inflammatory bowel disease. Although we performed an extensive work up, no clear pathophysiological cause could be diagnosed. Most likely, myocardial infarction was associated with a hypercoagulative state related to systemic inflammation. CONCLUSION: The mechanisms of coagulation disturbances in the context of acute and chronic inflammation are not yet fully understood. A better understanding of cardiovascular events in patients with inflammatory bowel disease might lead to new treatment approaches of cardiovascular disease.

[Chest pain and cardiovascular diseases in women : Diagnostics and treatment]. / Brustschmerz und kardiovaskuläre Erkrankungen bei Frauen : Diagnostik und Therapie.

Cardiovascular diseases (CVD) are the leading cause of global mortality not only in men but also in women. The incidence of CVD significantly increases in women, especially after the menopause. Sex and gender differences in the incidence, prevalence and mortality of CVD are due to hormonal, anatomical, and sociocultural differences. As part of the primary and secondary prevention of coronary heart disease (CHD), risk factors specific for women, such as autoimmune diseases and pregnancy-associated diseases (e.g., gestational diabetes and pre-eclampsia) should also be taken into account in addition to the classical cardiovascular risk factors. Furthermore, in women with angina pectoris it should be considered that women in particular frequently suffer from ischemia with nonobstructive coronary arteries (INOCA) that can be caused, for example, by coronary microvascular dysfunction (CMD) or coronary spasms. Based on this, the diagnostics should not be terminated in symptomatic women after coronary angiography with normal epicardial vessels. A targeted diagnostics for CMD and coronary spasms should be carried out at an early stage.

Chest pain with ST-elevation in leads AVR, III, AVF, V1, V3R, V4R and V5R.

We mistakenly diagnosed a patient with pulmonary embolism as ST-elevation acute myocardial infarction. The case complained of chest pain with ST-elevation in leads AVR, III, AVF, V1, V3R, V4R and V5R. In addition, we also found ST- elevation AVR, III>ST- elevation AVF, QIII>QAVF and QV1. Multi-site pulmonary embolism can lead to type 2 myocardial infarction or special type of myocardial infarction with non-obstructive coronary arteries through multiple pathological mechanisms.

Contemporary Diagnosis and Management of Patients with MINOCA.

PURPOSE OF REVIEW: Myocardial infarction with nonobstructive coronary arteries (MINOCA) is defined as acute myocardial infarction (MI) with angiographically no obstructive coronary artery disease or stenosis ≤ 50%. MINOCA is diagnostically challenging and complex, making it difficult to manage effectively. This condition accounts for 6-8% of all MI and poses an increased risk of morbidity and mortality after diagnosis. Prompt recognition and targeted management are essential to improve outcomes and our understanding of this condition, but this process is not yet standardized. This article offers a comprehensive review of MINOCA, delving deep into its unique clinical profile, invasive and noninvasive diagnostic strategies for evaluating MINOCA in light of the lack of widespread availability for comprehensive testing, and current evidence surrounding targeted therapies for patients with MINOCA. RECENT FINDINGS: MINOCA is not uncommon and requires comprehensive assessment using various imaging modalities to evaluate it further. MINOCA is a heterogenous working diagnosis that requires thoughtful approach to diagnose the underlying disease responsible for MINOCA further.

MINOCA and INOCA: Role in Heart Failure.

PURPOSE OF REVIEW: Infarction (MINOCA) and ischaemia (INOCA) with non-obstructive coronary disease are recent non-conventional presentations of coronary syndromes that are increasingly recognised in the clinical arena, particularly with the availability of new cardiovascular imaging techniques. Both are related to heart failure (HF). MINOCA is not associated with benign outcomes, and HF is among the most prevalent events. Regarding INOCA, microvascular dysfunction has also been found to associate with HF, particularly with preserved ejection fraction (HFpEF). RECENT FINDINGS: Regardless of the several aetiologies underlying HF in MINOCA, it is likely related to LV dysfunction, where secondary prevention is not yet clearly established. Regarding INOCA, coronary microvascular ischaemia has been associated to endothelial dysfunction leading ultimately to diastolic dysfunction and HFpEF. MINOCA and INOCA are clearly related to HF. In both, there is a lack of studies on the identification of the risk factors for HF, diagnostic workup and, importantly, the appropriate primary and secondary prevention strategies.

Helicobacter pylori and Pro-Inflammatory Protein Biomarkers in Myocardial Infarction with and without Obstructive Coronary Artery Disease.

Myocardial infarction (MI) with obstructive coronary artery disease (MI-CAD) and MI in the absence of obstructive coronary artery disease (MINOCA) affect different populations and may have separate pathophysiological mechanisms, with greater inflammatory activity in MINOCA compared to MI-CAD. Helicobacter pylori (Hp) can cause systemic inflammation and has been associated with cardiovascular disease (CVD). We aimed to investigate whether Hp infection is associated with concentrations of protein biomarkers of inflammation and CVD. In a case-control study, patients with MINOCA (n = 99) in Sweden were included, complemented by matched subjects with MI-CAD (n = 99) and controls (n = 100). Protein biomarkers were measured with a proximity extension assay in plasma samples collected 3 months after MI. The seroprevalence of Hp and cytotoxin-associated gene A (CagA) was determined using ELISA. The associations between protein levels and Hp status were studied with linear regression. The prevalence of Hp was 20.2%, 19.2%, and 16.0% for MINOCA, MI-CAD, and controls, respectively (p = 0.73). Seven proteins were associated with Hp in an adjusted model: tissue plasminogen activator (tPA), interleukin-6 (IL-6), myeloperoxidase (MPO), TNF-related activation-induced cytokine (TRANCE), pappalysin-1 (PAPPA), soluble urokinase plasminogen activator receptor (suPAR), and P-selectin glycoprotein ligand 1 (PSGL-1). Hp infection was present in one in five patients with MI, irrespective of the presence of obstructive CAD. Inflammatory proteins were elevated in Hp-positive subjects, thus not ruling out that Hp may promote an inflammatory response and potentially contribute to the development of CVD.

Myocarditis Presenting as Myocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA) in a Young Man: A Case Report.

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a unique disorder that manifests as an acute myocardial infarction clinically without overt coronary arteries obstruction on angiography. Herein, we report a 17-year-old male presented with a chest pain occurring 3 hours before admission and fever lasting for 2 days. Electrocardiogram examination showed ST elevation in lead II, III, aVF and V3-V6. Laboratory tests results showed a normal leukocyte level of 9850/µL, an elevated troponin of 3.55 ng/mL and an elevated quantitative CRP of 46 mg/L. Coronary angiography performed, indicating 20-30% stenosis of the left anterior descending artery, left circumflex artery and right coronary artery, whereas in typical acute myocardial injury, angiography shows >50% coronary stenosis. Additional cardiac MRI examination showed a fulfillment of Lake Louis Criteria for myocarditis, with further findings of acute myocardial edema in the lateral wall of left ventricle, with left ventricle ejection fraction of 59.73%. As researchers are still working on the definition of MINOCA, present knowledge of the causes, pathophysiology, clinical features, or specific phenotypes of MINOCA is also limited. A stepwise diagnostic approach is needed to diagnose MINOCA, with subsequent differential diagnosis exclusion.

Desmoplakin cardiomyopathy-an inherited cardiomyopathy presenting with recurrent episodes of acute myocardial injury.

We present two female patients with recurrent episodes of myocardial injury, consisting of acute chest pain and elevated cardiac markers without coronary artery disease. Cardiovascular magnetic resonance imaging identified extensive late gadolinium enhancement suggestive of an inherited cardiomyopathy. Genetic testing showed heterozygous pathogenic variants in the desmoplakin (DSP) gene, the gene coding for the desmoplakin protein, a structural protein found in the cardiac desmosome. Pathogenic variants in the DSP gene are associated with dilated and arrhythmogenic cardiomyopathy. DSP cardiomyopathies may cause recurring myocardial injury mimicking an acute coronary syndrome or myocarditis. Cardiac magnetic resonance imaging is key in its diagnosis due to its specifying imaging features. Genetic testing is essential for the evaluation and confirmation of the diagnosis.

Prevalence, characteristics and outcome of cardiac manifestations in critically-ill antiphospholipid syndrome patients.

AIMS: Antiphospholipid syndrome (APS) is a rare autoimmune disease defined by thrombotic events occurring in patients with persistent antiphospholipid antibodies. Cardiac manifestations in critically-ill APS patients are poorly investigated. We conducted a study to assess the prevalence, the characteristics and the prognosis of cardiac manifestations in thrombotic APS patients admitted to intensive care unit (ICU). METHODS AND RESULTS: A French, national, multicentre, retrospective study, conducted, from January 2000 to September 2018, including all APS patients admitted to 24 participating centres' ICUs with any new thrombotic (arterial, venous or microvascular) manifestation. Cardiac manifestations were defined as any new cardiac abnormalities relying on clinical examination, cardiac biomarkers, echocardiography, cardiac magnetic resonance (CMR) and coronarography. One hundred and thirty-six patients (female 72%) were included. Mean age at ICU admission was 46 ± 15years. Cardiac manifestations were present in 71 patients (53%). In patients with cardiac involvement, median left ventricular ejection fraction (LVEF) was 40% [28-55], troponin was elevated in 93% patients, coronary angiogram (n = 19, 27%) disclosing a coronary obstruction in 21%. CMR (n = 21) was abnormal in all cases, with late gadolinium enhancement in 62% of cases. Cardiac manifestations were associated with a non-significant increase of mortality (32% vs. 19%, p = 0.08). After 1-year follow-up, median LVEF was 57% [44-60] in patients with cardiac involvement. CONCLUSION: Cardiac involvement is frequent in critically-ill thrombotic APS patients and may be associated to more severe outcome. Increased awareness on this rare cause of myocardial infarction with or without obstructive coronary artery is urgently needed.

Invasive Functional Coronary Assessment in Myocardial Ischemia with Non-Obstructive Coronary Arteries: from Pathophysiological Mechanisms to Clinical Implications.

Despite ischemic heart disease (IHD) has been commonly identified as the consequence of obstructive coronary artery disease (OCAD), a significant percentage of patients undergoing coronary angiography because of signs and/or symptoms of myocardial ischemia do not have any significant coronary artery stenosis. Several mechanisms other than coronary atherosclerosis, including coronary microvascular dysfunction (CMD), coronary endothelial dysfunction and epicardial coronary vasospasm, can determine myocardial ischemia or even myocardial infarction in the absence of flow-limiting epicardial coronary stenosis, highlighting the need of performing adjunctive diagnostic tests at the time of coronary angiography to achieve a correct diagnosis. This review provides updated evidence of the pathophysiologic mechanisms of myocardial ischemia with non-obstructive coronary arteries, focusing on the diagnostic and therapeutic implications of performing a comprehensive invasive functional evaluation consisting of the assessment of both vasodilation and vasoconstriction disorders. Moreover, performing a comprehensive invasive functional assessment may have important prognostic and therapeutic implications both in patients presenting with myocardial ischemia with non-obstructive coronary arteries (INOCA) or myocardial infarction with non-obstructive coronary arteries (MINOCA), as the implementation of a tailored patient management demonstrated to improve patient's symptoms and prognosis. However, given the limited knowledge of myocardial ischaemia with non-obstructive coronary arteries, there are no specific therapeutic interventions for these patients, and further research is warranted aiming to elucidate the underlying mechanisms and risk factors and to develop personalized forms of treatment.

Acute Complications in Patients with Myocardial Infarction with Non-Obstructive Coronary Arteries: A Systematic Review with Special Focus on Mechanical Complications.

Background: Recently, we have observed an increasing focus on myocardial infarction (MI) with non-obstructive coronary arteries (MINOCA) patients. MINOCA incidence is estimated to be within the range of 5-15% of all MI cases. Unfortunately, MINOCA relates to various conditions that are not rarely hard to identify, including coronary microcirculation dysfunction, epicardial coronary spasm, or plaque erosion. Our systematic review aimed to identify and appraise previous studies which characterized acute complications, with particular focus on mechanical complications, in patients with MINOCA. Methods: Applying the MeSH strategy in PubMed and Embase, two operators independently and systematically reviewed published studies on patients diagnosed with MINOCA and in whom acute complications were described. Papers published in the last 10 years (June 2012-June 2022) to reflect the introduction of the MINOCA definition as well as the current clinical practice were analyzed. The research was conducted in July 2022. Results: The search yielded 192 records. After abstract review, 79 papers were left, and after full-text analysis, we finally included 20 studies. Among 20 studies, there were: one randomized controlled trial, one prospective study, five retrospective studies, 1 case series, and 12 case reports with a total number of 337,385 patients. In the identified literature, we revealed 7 cases of intraventricular septal rupture, 3 cases of free wall rupture with pericardial effusion or cardiac tamponade, and 3 cases of bleeding complications (intracerebral or intestinal bleeding). Moreover, the ventricular arrhythmia incidence ranged from 2% to 13.8%, and the in-hospital death rate ranged from 0.9% to 6.4%. Conclusions: These findings suggest that MINOCA patients should be treated as standard MI patients with watchful monitoring, especially in the first few days.

Myocardial Infarction with Non-Obstructive Coronary Arteries: A Puzzle in Search of a Solution.

Background: The term myocardial infarction with non-obstructive coronary arteries (MINOCA), defines a puzzling event occurring in the absence of obstructive coronary artery disease on coronary angiography and without an overt potential cause. However, a practical diagnostic work-up is often difficult, due to the heterogeneous etiologies and pathophysiology of MINOCA. This review aims to provide a comprehensive overview focusing on epidemiology, etiopathogenesis, diagnostic tools and therapeutic strategies for subjects with MINOCA, in order to provide a prompt and accurate diagnostic work-up and an adequate therapeutic approach in this subset population. Methods: This educational review was carried out by following the standard methods of the Cochrane Collaboration and the PRISMA statement. The terms "MINOCA" OR ("myocardial infarction" AND ("non-obstructive" OR "non-obstructive")) were searched in PubMed and Embase databases (in Title and/or Abstract) from 1st January 2003 until 31st May 2022. Results: Etiologic findings, clinical presentation and the degree of hemodynamic impairment play a pivotal role in defining the patient's natural history and prognostic outcome, and may significantly impact on the decision-making strategies and therapeutic approaches. Conclusions: Despite further advances in diagnostic and therapeutic strategies, MINOCA remains a challenging conundrum in clinical practice. Clinicians should be aware of the different potential etiologies and pathogenic mechanisms of MINOCA, in order to carry out a comprehensive diagnostic work-up and implement a tailored therapeutic approach.