Myocardial infarction with normal coronary arteries: a conundrum with multiple aetiologies and variable prognosis: an update

Sex-specific and ethnicity-specific differences in MINOCA

Suspected myocardial infarction with non-obstructive coronary arteries (MINOCA) has received increasing attention over the past decade. Given the heterogeneity in the mechanisms underlying acute myocardial infarction in the absence of obstructive coronary arteries, the syndrome of MINOCA is considered a working diagnosis that requires further investigation after diagnostic angiography studies have been performed, including coronary magnetic resonance angiography and functional angiography. Although once considered an infrequent and low-risk form of myocardial infarction, recent data have shown that the prognosis of MINOCA is not as benign as previously assumed. However, despite increasing awareness of the condition, many questions remain regarding the diagnosis, risk stratification and treatment of MINOCA. Women seem to be more susceptible to MINOCA, but studies on the sex-specific differences of the disease are scarce. Similarly, ethnicity-specific factors might explain discrepancies in the observed prevalence or underlying pathophysiological mechanisms of MINOCA but data are also scarce. Therefore, in this Review, we provide an update on the latest evidence available on the sex-specific and ethnicity-specific differences in the clinical features, pathophysiological mechanisms, treatment and prognosis of MINOCA.

Diagnostic Puzzles and Cause-Targeted Treatment Strategies in Myocardial Infarction with Non-Obstructive Coronary Arteries: An Updated Review

Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a distinct subtype of myocardial infarction (MI), occurring in about 8-10% of spontaneous MI cases referred for coronary angiography. Unlike MI with obstructive coronary artery disease, MINOCA's pathogenesis is more intricate and heterogeneous, involving mechanisms such as coronary thromboembolism, coronary vasospasm, microvascular dysfunction, dissection, or plaque rupture. Diagnosing MINOCA presents challenges and includes invasive and non-invasive strategies aiming to differentiate it from alternative diagnoses and confirm the criteria of elevated cardiac biomarkers, non-obstructive coronary arteries, and the absence of alternate explanations for the acute presentation. Tailored management strategies for MINOCA hinge on identifying the underlying cause of the infarction, necessitating systematic diagnostic approaches. Furthermore, determining the optimal post-MINOCA medication regimen remains uncertain. This review aims to comprehensively address the current state of knowledge, encompassing diagnostic and therapeutic approaches, in the context of MINOCA while also highlighting the evolving landscape and future directions for advancing our understanding and management of this intricate myocardial infarction subtype.

An Incidental Myxoma Hidden in Chest Pain

Chest pain is a very common symptom in an emergency context. Its differential diagnosis is extensive and includes some conditions that require immediate recognition and intervention. It can also be a symptom associated with rarer diagnostic possibilities. Here, we report the case of a 53-year-old woman admitted to the emergency department due to chest pain and initially diagnosed with non-ST elevation acute myocardial infarction. A transthoracic echocardiogram revealed a large hyperechogenic round mass, suggestive of a left atrial cardiac myxoma. Coronary angiography showed no significant lesions. The patient underwent cardiac surgery with excision of the mass, whose histological diagnosis was atrial myxoma. The immediate postoperative period was uneventful, and the patient was discharged asymptomatic and without echocardiographic changes. Cardiac tumors are a rare finding, of which myxomas are the most common. Symptoms can typically result from embolism, obstruction, or constitutional symptoms. A myxoma presenting as acute chest pain and mimicking an acute coronary syndrome is an uncommon finding. This case reminds us of an extremely rare differential diagnosis of chest pain and awakens us to the usefulness and importance of using echocardiography as a diagnostic tool.

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.

Diagnostic and Prognostic Role of Cardiac Magnetic Resonance in MINOCA: Systematic Review and Meta-Analysis

BACKGROUND

Myocardial infarction with nonobstructive coronary arteries (MINOCA) is common in current clinical practice. Cardiac magnetic resonance (CMR) plays an important role in its management and is increasingly recommended by all the current guidelines. However, the prognostic value of CMR in patients with MINOCA is still undetermined.

OBJECTIVES

The purpose of this study was to determine the diagnostic and prognostic value of CMR in the management of patients with MINOCA.

METHODS

A systematic review was performed to identify studies reporting the results of CMR findings in patients with MINOCA. Random effects models were used to determine the prevalence of different disease entities: myocarditis, myocardial infarction (MI), or takotsubo syndrome. Pooled odds ratios (ORs) and 95% CIs were calculated to evaluate the prognostic value of CMR diagnosis in the subgroup of studies that reported clinical outcomes.

RESULTS

A total of 26 studies comprising 3,624 patients were included. The mean age was 54.2 ± 5.3 years, and 56% were men. MINOCA was confirmed in only 22% (95% CI: 0.17-0.26) of the cases and 68% of patients with initial MINOCA were reclassified after the CMR assessment. The pooled prevalence of myocarditis was 31% (95% CI: 0.25-0.39), and takotsubo syndrome 10% (95% CI: 0.06-0.12). In a subgroup analysis of 5 studies (770 patients) that reported clinical outcomes, CMR diagnosis of confirmed MI was associated with an increased risk of major adverse cardiovascular events (pooled OR: 2.40; 95% CI: 1.60-3.59).

CONCLUSIONS

In patients with MINOCA, CMR has been demonstrated to add an important diagnostic and prognostic value, proving to be crucial for the diagnosis of this condition. Sixty-eight percent of patients with initial MINOCA were reclassified after the CMR evaluation. CMR-confirmed diagnosis of MINOCA was associated with an increased risk of major adverse cardiovascular events at follow-up.

A Left Atrial Myxoma Masquerading As Acute Coronary Syndrome

Acute coronary syndrome is caused by a rupture of atherosclerotic plaque with superimposed thrombus formation. Non-ST-segment elevation acute coronary syndrome (NSTE-ACS) occurs when occlusion of the epicardial coronary artery by a thrombus causes partial thickness myocardial ischemia and an ischemic cascade downstream. Cardiac masses are known to produce symptoms predominantly by local obstruction or systemic embolism. Coronary artery tumor embolism causing acute coronary syndrome is a rare presentation of cardiac mass. We report NSTE-ACS as the initial presentation of the left atrial myxoma in a 62-year-old woman. She presented to the emergency department with acute onset severe anginal chest pain, diaphoresis, and dizziness. Her serial electrocardiograms (ECGs) were normal, and serial troponins were elevated, consistent with non-ST-segment elevation acute coronary syndrome. Cardiac catheterization revealed insignificant coronary artery disease, and transthoracic and transesophageal echocardiograms showed a left atrial mass attached to the interatrial septum consistent with myxoma. The patient underwent surgical excision, and histopathology was consistent with myxoma. Her symptoms subsided after surgery. Primary cardiac tumors are very uncommon and can present with myriad symptoms, from tumor embolism, local cardiac effects, to constitutional symptoms. Although embolism to other organs has been reported, left atrial myxoma presenting as an acute coronary syndrome is very uncommon.

Case Report: Free-Floating Intracoronary Thrombus: Who Is the Convict?

In young patients, especially with no traditional coronary risk factors, hypercoagulable states may always be considered as an alternative cause of acute coronary syndromes. The concomitant thrombotic and bleeding risk associated with myeloproliferative disorders complicates the decision-making, particularly regarding long-term dual antiplatelet therapy. The chosen therapy may need to be frequently revisited, depending on the patient's bleeding complications. We reported the case of a 49-year-old woman with acute myocardial infarction with no traditional risk factors for coronary artery disease where a myeloproliferative neoplasm was diagnosed.

Diagnostic value of Cardiac Magnetic Resonance Imaging and Intracoronary Optical Coherence Tomography in patients with a working diagnosis of Myocardial Infarction with Non-obstructive Coronary Arteries - A Systematic review and Meta-analysis

BACKGROUND

We aimed to study the efficacy of cardiac magnetic resonance imaging (CMR) and intracoronary optical coherence tomography (OCT) in detecting the etiology of myocardial infarction with non-obstructive coronary arteries (MINOCA).

METHODS

A systematic search was conducted in PubMed, Medline, and Cochrane databases. Search terms used: Myocardial infarction, Coronary angiography, Normal coronary arteries, CMR, and OCT. Inclusion criteria was fulfilled by 18 studies. Meta-analysis was performed with 15 studies.

RESULTS

A total of 2697 patients were included. The mean age of all the patients was 51.5 and 56.4% were men. CMR established diagnosis in 74% of the patients; 29% had acute myocarditis, 18% had true myocardial infarction and 12% had takotsubo cardiomyopathy. Combining OCT with CMR was better at finding the etiology than either modality individually.

CONCLUSION

CMR is integral in identifying the etiology of MINOCA. Coupling OCT and CMR is better than either technique individually at finding the cause.

Acute myocardial infarction in a young man with ankylosing spondylitis: A case report

BACKGROUND

Ankylosing spondylitis (AS) is a chronic progressive inflammatory disease that mainly affects the spine and sacroiliac joints. To the best of our knowledge, AS with acute myocardial infarction (AMI) has rarely been reported. Here, we report an unusual case of AS with AMI in a young patient.

CASE SUMMARY

A 37-year-old man was admitted to the Department of Rheumatology and Immunology of our hospital on March 14, 2020, for low back pain. Further evaluation with clinical examinations, laboratory tests, and imaging resulted in a diagnosis of AS. Treatment with a non-steroidal anti-inflammatory drug and a tumor necrosis factor inhibitor partially improved his symptoms. However, his back pain persisted. After 6 wk of treatment, he was admitted to the emergency room of another hospital in this city for sudden-onset severe chest pain consistent with a diagnosis of AMI. Angiography revealed severe narrowing of the coronary arteries. Surgical placement of two coronary stents completely relieved his back pain.

CONCLUSION

AS can cause cardiovascular diseases, including AMI. It is important to consider the cardiovascular risks in the management of AS.

How I treat unexplained arterial thrombosis

Most arterial thrombotic events have a clear atherosclerotic or cardioembolic etiology, but hematologists are frequently asked to assist in the diagnosis and management of a patient with a nonatherosclerotic and noncardioembolic arterial event, referred to here as an unexplained arterial thrombosis. Because there is an assorted list of factors that can precipitate an arterial event, we present a systematic diagnostic approach to ensure consideration of not only primary hypercoagulable disorders, but also pro-thrombotic medications or substances, vascular and anatomic abnormalities, and undiagnosed systemic disorders, such as malignancy and autoimmune diseases. We also review existing literature of the role of hypercoagulable disorders in arterial thrombosis and discuss our approach to thrombophilia workup in patients after an unexplained arterial event. We conclude with 3 representative cases to both illustrate the application of the outlined diagnostic schema and discuss common management considerations, specifically the selection of anticoagulation vs antiplatelet therapy for secondary prevention.

Risk factor comparison in young patients presenting with acute coronary syndrome with atherosclerotic coronary artery disease vs. angiographically normal coronaries

Background: Acute myocardial infarction is a relatively rare phenomenon in the young population. The incidence has nevertheless increased from years past, likely due to the presence of multiple risk factors from an increasingly younger age. Regardless of whether they have atherosclerotic coronary artery disease or normal coronary angiogram, young patients with risk factors for coronary artery disease (CAD), chest pain, and positive troponin, are initially treated in a similar fashion. Our goal was to shed light on whether risk factors between these two groups differ to help guide physicians in clinically determining whether or not an atherosclerotic cardiovascular event has occurred, as well as to potentially identify young patients at risk of acute coronary syndrome (ACS) despite normal coronary arteries. Methods: A retrospective cross sectional study was undertaken over an 8 year period at Tawam Hospital. 576 patients aged 50 or under who underwent coronary angiography were selected for the study. Medical records were analyzed for the patient's demographics and CAD risk factor profile, including the following variables: family history of CAD, smoking status, Body Mass Index category, lipid profile, and diagnosis of hyperlipidemia, diabetes, or hypertension. Details of the coronary angiogram were also reviewed. Results: Statistically significant outcomes included a higher prevalence of diabetes, hyperlipidemia, and smoking history in patients with CAD compared to the patients with normal coronary angiogram. Diabetes was one of the strongest risk factors in CAD patients, with an odds ratio of 1.98 (p= 0.011), followed by hyperlipidemia at 1.85 (p= 0.021). Smoking history had an odds ratio of 2.93 (p <0.001). Conclusion: Risk factors were present in both groups, but significantly more in the CAD group. No particular risk factor stood out for the development of ACS in those with normal coronary arteries, other than mean BMI being slightly higher in this group. Based on our analysis, no single variable can accurately predict the risk for ACS in normal coronaries. To our knowledge, few studies have been done in the young population with angiographically normal coronary arteries to determine possible risk factors for development of ACS. Further research needs to be done to determine whether the risk factors that were common amongst both groups are coincidental, or a cause of ACS in those with normal coronary arteries.

Myocardial Infarction With Nonobstructive Coronary Arteries

Myocardial infarction with nonobstructive coronary arteries (MINOCA) is the current term used to describe patients who have a myocardial infarction but have normal, non-obstructed coronary arteries on a coronary angiogram. There is still much debate over the definition, diagnosis, management and treatment of MINOCA. However, MINOCA is not a benign condition; prompt recognition and diagnosis can lead to better management and treatment and thus improve patient outcomes. This review article will update the most recent definition of MINOCA, discuss epidemiology and etiology, and review the diagnostic workup and management options for patients presenting with signs and symptoms of MINOCA.

Myocardial Infarction With Nonobstructive Coronary Arteries (MINOCA): Potential Etiologies, Mimics and Imaging Findings

Myocardial infarction with nonobstructive coronary arteries (MINOCA) occurs when a patient presents with positive cardiac enzymes in the absence of obstructive atherosclerosis on coronary angiography. Several hypotheses for the pathogenesis of MINOCA have been suggested and multiple potential underlying etiologies have been reported. This review will outline the reported causes of MINOCA and associated major imaging features. In doing so, it will increase awareness of this entity and equip cardiac imagers with the knowledge to appropriately tailor imaging to make a prompt and accurate diagnosis.

Molecular and Nonmolecular Magnetic Resonance Coronary and Carotid Imaging

Atherosclerosis is the leading cause of cardiovascular morbidity and mortality. Over the past 2 decades, increasing research attention is converging on the early detection and monitoring of atherosclerotic plaque. Among several invasive and noninvasive imaging modalities, magnetic resonance imaging (MRI) is emerging as a promising option. Advantages include its versatility, excellent soft tissue contrast for plaque characterization and lack of ionizing radiation. In this review, we will explore the recent advances in multicontrast and multiparametric imaging sequences that are bringing the aspiration of simultaneous arterial lumen, vessel wall, and plaque characterization closer to clinical feasibility. We also discuss the latest advances in molecular magnetic resonance and multimodal atherosclerosis imaging.

A microvascular myocardial infarction in a 16-year-old girl with antiphospholipid syndrome: a case report

Objective and importance: The antiphospholipid syndrome can manifest itself by silent (or not) myocardial infarction. Clinical presentation: We report the case of a 16-year-old girl who presented a myocardial infarction for whom a coronary-computer tomography did not reveal any coronary abnormalities or obstruction. She had a livedo reticularis on her physical exam. Intervention: The echocardiography showed a normal left ventricular function and a mild eccentric mitral regurgitation. A myocardial magnetic resonance imaging demonstrated transmural necrosis with microvascular obstruction at the inferobasal segment of the left ventricle, suggestive of a microvascular myocardial infarction. The blood test showed elevation of the three antiphospholipid antibodies (lupus anticoagulant, anticardiolipin, and anti-β2-glycoprotein). The lupus anticoagulant remained positive 12 weeks later, fulfilling the laboratory criteria for antiphospolipid carrier. The associated presence of this microvascular coronary obstruction was strongly suggestive of antiphospholipd syndrome, according to the revised Sapporo criteria. To our knowledge, this is the first reported case of antiphospholipid syndrome manifesting as an acute microvascular myocardial infarction, confirmed by myocardial magnetic resonance imaging. Conclusion: The antiphospholipid syndrome can manifest itself early by a microvascular myocardial infarction. The clinician has to be alerted by a livedo reticularis in these patients, which will be frequently associated with manifestations of antiphospholipid syndrome such as arterial thrombosis and valvulopathies.

[Vasospastic angina: An under-diagnosed pathology]

The clinical and physiopathological clinical entity known as spastic angina or variant angina has been long documented. It remains, however, an under-estimated condition, which is insufficiently diagnosed and explored. This pathology is associated with severe complications such as heart rhythm disorders, which may potentially result in ventricular fibrillation and cause sudden death. In Japan, this condition occurs more frequently and is better documented. Stimulation tests are also carried out more often and have a higher positivity rate than in France where vasospastic angina is less frequently reported and where provocation tests are associated with negative results and are, consequently, performed less often. In order to improve the detection of this pathology, its potential presence should be explored in patients with rest angina who experience chest pain in the second half of the night and also in instances of acute coronary syndrome with sudden death and no angiographically visible coronary artery disease. The diagnosis should be confirmed by means of ergonovine provocation tests. In order to enhance the sensitivity of these tests without increasing the risk of complications, injection of ergonovine should be preferably carried out via the intracoronary route. By increasing the frequency and sensitivity of these tests, this pathology, which responds well to medical treatment in many cases, could be amenable to therapeutic management as any other form of coronary artery disease.

Factors Associated with Sub-intimal Coronary Artery Dissection in MINOCA Patients with Delayed Washout at Coronary Angiography – Protocol for an Observational, OCT-based Study

Background: Myocardial infarction (MI) with no obstructive coronary arteries (MINOCA) is a special form of the acute coronary syndrome. The heterogeneous pathophysiology of MINOCA is not well elucidated and includes cardiac and non-cardiac causes. Slow flow phenomenon on coronary angiography can be associated with several possible causes of MINOCA confirmed by optical coherence tomography (OCT). Therefore, the aim of this study is to assess the underlying mechanism of the delayed washout phenomenon on coronary angiography and the potential role of subintimal coronary artery dissection (SD) in the setting of an acute MI.

Methods and design: This clinical prospective, descriptive research will enroll patients diagnosed with acute MI (STEMI or NSTEMI) identified by coronary angiography, followed by OCT imaging of the coronary arteries at the Emergency Clinical County Hospital of Târgu Mureş, Romania. The enrolled patients will be separated into two groups based on OCT examination, patients with SD and patients with no SD.

Conclusion: The underlying mechanisms of MINOCA with delayed washout phenomenon on coronary angiography is still poorly understood. Modern invasive imaging techniques are capable to assess the microstructure of the coronary artery wall and are able to offer the much needed information to elucidate the pathophysiological changes which ultimately cause the acute event. The current study offers a new, complex – clinical, invasive and noninvasive imaging, as well as biomarker-based – approach, which may lead to a better understanding and treatment of this pathology.

[Coronary spasm a diagnostic and therapeutic challenge]

Vasospastic angina is a clinical and physio-pathological entity, which has been documented for many years, but its diagnosis is under-estimated despite the fact that though inadequately considered and investigated. This condition is potentially serious and can sometimes trigger severe arrhythmia resulting in ventricular fibrillation and sudden death. This pathology has a higher incidence in Asia, where it is, therefore, better documented with provocative testing being carried out more frequently, while in France, these tests are not sufficiently performed probably due to the fact that they often produce negative findings. Provocative tests with Ergonovine injection should be performed via intra-coronary to improve its sensibility. Should this test become more sensitive and more routinely performed, this condition, which often responds well to medical treatment, could regain appropriate recognition as a coronary disease.

Presentation, Clinical Profile, and Prognosis of Young Patients With Myocardial Infarction With Nonobstructive Coronary Arteries (MINOCA): Results From the VIRGO Study

BACKGROUND

We compared the clinical characteristics and outcomes of young patients with myocardial infarction with nonobstructive coronary arteries (MINOCA) versus obstructive disease (myocardial infarction due to coronary artery disease [MI-CAD]) and among patients with MINOCA by sex and subtype.

METHODS AND RESULTS

Between 2008 and 2012, VIRGO (Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients) prospectively enrolled acute myocardial infarction patients aged 18 to 55 years in 103 hospitals at a 2:1 ratio of women to men. Using an angiographically driven taxonomy, we defined patients as having MI-CAD if there was revascularization or plaque ≥50% and as having MINOCA if there was <50% obstruction or a nonplaque mechanism. Patients who did not have an angiogram or who received thrombolytics before an angiogram were excluded. Outcomes included 1- and 12-month mortality and functional (Seattle Angina Questionnaire [SAQ]) and psychosocial status. Of 2690 patients undergoing angiography, 2374 (88.4%) had MI-CAD, 299 (11.1%) had MINOCA, and 17 (0.6%) remained unclassified. Women had 5 times higher odds of having MINOCA than men (14.9% versus 3.5%; odds ratio: 4.84; 95% confidence interval, 3.29-7.13). MINOCA patients were more likely to be without traditional cardiac risk factors (8.7% versus 1.3%; P<0.001) but more predisposed to hypercoaguable states than MI-CAD patients (3.0% versus 1.3%; P=0.036). Women with MI-CAD were more likely than those with MINOCA to be menopausal (55.2% versus 41.2%; P<0.001) or to have a history of gestational diabetes mellitus (16.8% versus 11.0%; P=0.028). The MINOCA mechanisms varied: a nonplaque mechanism was identified for 75 patients (25.1%), and their clinical profiles and management also varied. One- and 12-month mortality with MINOCA and MI-CAD was similar (1-month: 1.1% and 1.7% [P=0.43]; 12-month: 0.6% and 2.3% [P=0.68], respectively), as was adjusted 12-month SAQ quality of life (76.5 versus 73.5, respectively; P=0.06).

CONCLUSIONS

Young patients with MINOCA were more likely women, had a heterogeneous mechanistic profile, and had clinical outcomes that were comparable to those of MI-CAD patients.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00597922.

Posterobasal left ventricular aneurysm after myocardial infarction with normal coronary arteries: Case-report

We present a case of a 64-year-old woman with signs of debilitating condition including anginal chest pain, exertional dyspnea, and depression. The patient had previously suffered from a myocardial infarction after a loss of a close family member. Workup showed a posterobasal left ventricular aneurysm and moderate to severe mitral regurgitation in the absence of coronary atherosclerosis. Routine ultrasonography revealed abdominal aortic aneurysm and intraabdominal aortic deviation. The patient was immediately started on optimal medical treatment. On repeat assessment general condition was satisfactory, vital signs were normal, and investigations showed no signs of progressive heart failure or other significant clinical changes. Although prognosis in patients with myocardial infarction with normal coronary arteries is generally considered favorable, mechanical complications such as posterobasal left ventricular aneurysm with moderate to severe mitral regurgitation are possible.

Risk of Thrombosis in Patients Presenting with Myocardial Infarction with Nonobstructive Coronary Arteries (MINOCA)

Patients presenting with myocardial infarction (MI) in the absence of obstructive coronary artery disease (CAD) is termed MI with nonobstructive coronary arteries (MINOCA). The underlying pathophysiology of MINOCA is multifactorial and in situ formation and subsequent spontaneous lysis of a coronary thrombus is often hypothesized as one of the mechanisms. The objective of this study is to determine whether MINOCA patients had a greater prothrombotic tendency in comparison to MI patients with obstructive CAD (MICAD). Prospectively, blood samples of 25 consecutive MINOCA patients (58 (interquartile range [IQR]: 48, 75) years, 48% women) and 25 age-/gender-matched MICAD patients (58 (IQR: 50, 66) years, 48% women) were obtained at 1 month after the initial presentation and overall thrombin generation potential and congenital/acquired thrombophilia states were assessed. As regard to results, overall thrombin generation parameters were similar ( p  > 0.05) between the MINOCA and MICAD groups, highlighting similar endogenous thrombin potential (1,590 nM/min; IQR: 1,380, 2,000 vs. 1,750 nM/min; IQR: 1,500, 2,040, respectively). There were no significant differences between MINOCA and MICAD, respectively, in respect to the numbers of patients with congenital thrombophilia states including factor V Leiden (0 vs. 4%) and prothrombin gene mutation (8 vs. 4%), decreased antithrombin (8 vs. 0%), protein C (0 vs. 0%), and protein S (4 vs. 0%). None of the patients demonstrated presence of lupus anticoagulant and anticardiolipin antibodies. Although MINOCA patients revealed thrombotic characteristics that are similar to those with MICAD, the results from this study are inconclusive and a larger study with healthy control subjects is required to assess the risk of thrombosis in MINOCA.

Predictors of adverse outcome in patients with myocardial infarction with non-obstructive coronary artery (MINOCA) disease

BACKGROUND

Myocardial infarction (MI) with non-obstructive coronary arteries (MINOCAs) is an increasingly recognized entity. No previous study has evaluated predictors for new major adverse cardiacvascular events (MACEs) and death in patients with MINOCA.

METHODS

We conducted an observational study of MINOCA patients recorded between July 2003 and June 2013 and followed until December 2013 for outcome events. Out of 199,163 MI admissions, 9092 consecutive unique patients with MINOCA were identified. The mean age was 65.5 years and 62% were women. MACE was defined as all-cause mortality, rehospitalization for acute MI, ischemic stroke and heart failure. Hazard ratio and 95% confidence interval (HR; 95% CI) was calculated using Cox-regression.

RESULTS

A total of 2147 patients (24%) experienced a new MACE and 1254 patients (14%) died during the mean follow-up of 4.5 years. Independent predictors for MACE after adjustment, were older age (1.05; 1.04-1.06), diabetes (1.44; 1.21-1.70), hypertension (1.25; 1.09-1.43), current smoking (1.38; 1.15-1.66), previous myocardial infarction (1.38; 1.04-2.82), previous stroke (1.69; 1.35-2.11), peripheral vascular disease (1.55; 1.97-2.23), chronic obstructive pulmonary disease (1.63; 1.32-2.00), reduced left ventricular ejection fraction (2.00; 1.54-2.60), lower level of total cholesterol (0.88; 0.83-0.94) and higher level of creatinine (1.01; 1.00-1.03). Independent predictors for all cause death were age, current smoking, diabetes, cancer, chronic obstructive pulmonary disease, previous stroke, reduced left ventricular fraction, lower level of total cholesterol and higher levels of creatinine and CRP.

CONCLUSIONS

The clinical factors predicting new MACE and death of MINOCA patients seem to be strikingly similar to factors previously shown to predict new cardiovascular events in patients with MI and obstructive coronary artery disease.

Characteristics and Long-Term Prognosis of Patients ≤35 Years of Age with ST Segment Elevation Myocardial Infarction and "Normal or Near Normal" Coronary Arteries

There are scarce data regarding risk factors and prognosis of patients with premature ST segment elevation myocardial infarction (STEMI) and "normal or near normal" coronary arteries (N/NNCAs). We compared the characteristics and long-term prognosis of patients with premature STEMI and N/NNCAs with their counterparts with significant coronary artery disease (CAD). We recruited 330 patients who had STEMI ≤35 years of age and 167 age- and gender-matched controls. All patients underwent coronary angiography. Coronary arteries with no lesions or lesions causing <30% reduction in lumen diameter were defined as N/NNCAs, whereas narrowings causing ≥50% diameter reduction formed the significant CAD group. Lipid profile, homocysteine levels, and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism were determined. Sixty patients (18%) had N/NNCAs. Patients with N/NNCAs had lower low-density lipoprotein-cholesterol and higher high-density lipoprotein-cholesterol levels, higher homocysteine levels, and higher prevalence of MTHFR TT genotype (34.6 vs 18%, p = 0.008) compared with patients with significant CAD. After a median follow-up of 8 years, cardiovascular events occurred in 105 (36%) of 291 patients with available follow-up data. Significant CAD was associated with higher risk for recurrent cardiovascular events after adjustment for traditional risk factors (hazard ratio 2.095, 95% confidence interval 1.088 to 3.664, p = 0.022) and additional adjustment for the left ventricular ejection fraction, reperfusion therapy, and persistent smoking (hazard ratio 1.869, 95% confidence interval 1.007 to 3.468, p = 0.041). In conclusion, patients with premature STEMI and N/NNCAs have fewer lipid abnormalities, higher homocysteine levels and prevalence of MTHFR TT genotype, and better long-term prognosis compared with their counterparts with significant CAD.

Congenital coronary artery anomalies in adults: review of 111 cases from a single-centre experience

BACKGROUND

Coronary artery anomalies are a heterogeneous group of congenital disorders presenting with a wide spectrum of symptoms, ranging from vague chest pain to sudden cardiac death. Despite available data, there is no consensus about the classification, nomenclature, and outcomes of coronary anomalies in the normally connected heart. In this study, we aimed to investigate clinical and angiographic characteristics of coronary arterial anomalies, as well as the frequency of atherosclerotic involvement in anomalous coronaries, diagnosed at a tertiary referral centre.

METHODS

We retrospectively reviewed coronary angiograms performed between 2011 and 2015 for the presence of a coronary anomaly. A total of 111 patients with a final diagnosis of coronary anomaly were included in the study group. We also recruited 110 age- and sex-matched patients who underwent coronary angiography because of symptomatic coronary artery disease as controls.

RESULTS

Among 36,893 coronary angiograms, 111 (0.30%) major coronary anomalies were found. Compared with controls, the prevalence of significant atherosclerotic coronary disease was lower in patients with coronary anomalies and stable symptoms (p=0.02); however, the prevalence of significant coronary atherosclerosis was similar among patients admitted with unstable angina or myocardial infarction (p>0.05). Compared with controls, patients with an anomalous left anterior descending coronary artery had significantly less atherosclerotic involvement than those in whom the left anterior descending artery was not anomalous (p=0.005).

CONCLUSIONS

Although coronary artery anomalies are cited as a cause for myocardial ischaemia, atherosclerotic coronary artery disease is also frequent and may offer an alternative explanation to ischaemic symptoms. No predisposition to accelerated atherosclerosis was found, however, and atherosclerotic involvement was less frequent in some anomalous vessels.

Cardiac magnetic resonance in patients with acute cardiac injury and unobstructed coronary arteries

AIM

To define the role of cardiac magnetic resonance (CMR) by analyzing a particular group of patients with suspected acute coronary syndrome (ACS) and normal coronary angiogram.

METHODS

From January 2009 to December 2015, we examined 220 patients with clinical suspicion of ACS, Troponin elevation [the threshold used to define a positive Troponin T test (TnT) was 0.1 ng/mL] and no significant coronary disease at angiography (the patients were considered to have significant angiographic disease only a 50% stenosis was detected in any of their coronary arteries). The role of CMR with the late gadolinium enhancement was evaluated.

RESULTS

CMR was performed to 190 patients (86%) of this group which reveals: Myocarditis in 90 patients (47%); apical ballooning (Tako-Tsubo syndrome) in 32 patients (17%); myocardial infarction (MI) in 40 patients (21%) and no clear diagnosis identified by CMR in 28 patients (15%). A comparison with previous studies was also made. Clinical and echocardiographic follow-ups were performed at 12 ± 2 mo and no major adverse cardiac events were revealed.

CONCLUSION

There is a group of patients with clinical suspicion of ACS displaying normal coronary angiograms. CMR was demonstrated to be a valuable tool in the differential diagnosis evaluation of myocarditis, apical ballooning and MI.

Myocardial Infarction Without Obstructive Coronary Artery Disease is Not a Benign Condition (ANZACS-QI 10)

BACKGROUND

Non-obstructive coronary artery disease (CAD) on coronary angiography after myocardial infarction (MI) is associated with a lower risk of adverse outcomes, but the prognosis may not be benign. Our aim was to assess outcomes in MI with and without obstructive CAD, and in an age and sex matched comparison cohort without known cardiovascular disease.

METHODS

We performed a single centre analysis of consecutive patients undergoing coronary angiography for MI between 2007 and 2012. Patients were classified into those with obstructive CAD (≥50% epicardial coronary artery stenosis) and those without obstructive CAD (<50%). Myocardial infarction patient data was collected in an electronic registry and linked anonymously to national hospitalisation and mortality records. Age and sex matched patients without known CVD were identified from the community PREDICT cohort.

RESULTS

Of the 2070 patients with MI, 302 (15%) had non-obstructive CAD. Compared to patients with obstructive disease they were younger (mean 57 v 61 years, p<0.001), more likely to be women (50% vs 23%, p<0.001), to be of Maori or Pacific vs. European ethnicity (p<0.001), more likely to be lifelong non-smokers (46% v 38%, p=0.02), non-diabetic (80v 73%, p <0.01), have no ST-segment deviation (78% v 46%, p<0.001), and have a low risk Global Registry of Acute Coronary Events acute coronary syndrome (GRACE ACS) score (54 v 35%, p<0.001). They were also less likely to receive 'triple therapy' secondary prevention medications (81% v 94%, p<0.0001). The cumulative two-year Kaplan-Maier composite outcome of mortality or non-fatal MI was 14.3% for MI with obstructive CAD, 4.6% for MI without obstructive disease, and 2.2% for patients without prior CVD (p<0.001).

CONCLUSION

Myocardial infarction without obstructive coronary disease is common (∼1 in 7 patients) and is not clinically benign, with an adverse outcome rate double that of age and sex matched patients without CVD.

Risk of ventricular arrhythmia in patients with myocardial infarction and non-obstructive coronary arteries and normal ejection fraction

AIM

To assess the arrhythmic determinants and prognosis of patients presenting with myocardial infarction and non-obstructive coronary arteries (MINOCA) with normal ejection fraction (EF).

METHODS

This is an observational analysis of 131 MINOCA patients with normal EF. Three cardiac magnetic resonance (CMR) diagnosis classes were recognized according to the late gadolinium enhancement (LGE) pattern: Myocardial infarction (MI) (n = 34), myocarditis (n = 47), and “no LGE” (n = 50). Ventricular events occurring during hospitalization were recorded and the entire population was followed-up at 1 year.

RESULTS

Ventricular arrhythmia was observed in 18 (13.8%) patients during hospitalization. The “no LGE” patients experienced fewer ventricular events than the MI and myocarditis patients [4.0% vs 26.5% and 14.9%, respectively (P = 0.013)]. There was no significant difference between the MI and myocarditis groups. On multivariate analysis, LGE transmural extent [OR = 1.52 (1.08-2.15), P = 0.017] and ST-segment elevation [OR = 4.65 (1.61-13.40), P = 0.004] were independent predictors of ventricular arrhythmic events, irrespective of the diagnosis class. Finally, no patient experienced sudden cardiac death or ventricular arrhythmia recurrence at 1-year.

CONCLUSION

MINOCA patients with normal EF presented no 1-year cardiovascular events, irrespective of the CMR diagnosis class. LGE transmural extent and ST segment elevation at admission are risk markers of ventricular arrhythmia during hospitalization.

Usefulness of late gadolinium enhancement MRI combined with stress imaging in predictive significant coronary stenosis in new-diagnosed left ventricular dysfunction

BACKGROUND

To evaluate the accuracy of late gadolinium enhancement (LGE) cardiac magnetic resonance (CMR) and imaging stress test in predicting significant coronary artery disease (CAD) in left ventricular (LV) dysfunction.

METHODS

We enrolled 187 consecutive out-patients (61±17years) with new evidence of depressed (<45%) ejection fraction and no history of previous heart diseases and absence of Q-waves. All patients underwent coronary angiography (CA) and to LGE-CMR examination to identify ischemic and non-ischemic LGE. All patients underwent stress imaging to determine the presence of myocardial ischemia.

RESULTS

Ischemic-LGE was found in 83 patients and non-ischemic-LGE in 104. Significant CAD on CA was found in 86/187 patients. Ischemic-LGE showed a specificity of 94%, a sensitivity of 89% and an accuracy of 92% in identifying significant CAD. Imaging stress test was negative in 98/105 patients without CAD, and positive in 42/82 with significant CAD, showing a specificity of 93%, a sensitivity of 51% and an accuracy of 75% in identifying CAD. Combining CMR and stress test imaging, 94 patients had ischemic-LGE pattern and/or positive stress test for ischemia; of these 81/94 had significant CAD on CA and 13 had no CAD. Among the 93 patients with both tests negative, significant CAD was found in 5/93 patients. The combination of LGE and stress respect to only LGE did not improve the diagnostic accuracy (90 vs 92% respectively).

CONCLUSION

LGE-CMR had high accuracy in predicting significant CAD in ischemic LV dysfunction or as a bystander in non ischemic dysfunction.

Evaluation of Coronary Artery Status by Coronary Angiography after First Survival of Acute Myocardial Infarction

INTRODUCTION

Acute Myocardial Infarction (AMI) is a life threatening medical emergency which needs urgent medical attention. It is one of the major cause of mortality and morbidity throughout the world.

AIM

The aim of the present study was to assess the coronary artery status by Coronary Angiography (CAG) after first survival of the Acute Myocardial Infarction (AMI) and to correlate the CAG findings with Coronary Artery Disease (CAD) Risk Factor (RF) and effect of early thrombolysis.

MATERIALS AND METHODS

CAG was done on 870 patients consecutively from June 2013 to May 2015. Age, Gender, Body Mass Index (BMI), CAD risk factors (RF) such as Type 2 diabetes mellitus (T2 DM), hypertension, dyslipidaemia, smoking status and history of thrombolyctic status were recorded. The correlation between the CAD risk factors (RF) and the CAG findings were statistically analyzed.

RESULTS

Coronary heart disease risk factors analysis revealed ≥ three RF in 23.88%, two RF in 29.88% and one RFin 45.86% of patients. CAG showed Single Vessel Disease (SVD) in 236 (27.1%) patients, double vessel disease (DVD) in 220(25.2%) patients, Triple Vessel Disease (TVD) in 252 (28.9%) patients. Multiple coronary artery involvement were found in the high risk group patients, which was found statistically significant (p-value<0.0001). A total of 348/870 (40%) patients were thrombolysed amongst them 80 (22.9%) revealed minimal and/or normal coronary artery which was found statistically significant (p-value<0.0001).

CONCLUSION

Higher the coronary risk factors, more the chance of the multiple coronary arteries involvement. All AMI patients should be thrombolysed as early as possible to get the benefit of recanalization of the culprit vessel.

Myocardial infarction, symptomatic third degree atrioventricular block and pulmonary embolism caused by thalidomide: a case report

Background

Thalidomide has been reported to cause numerous thromboembolic events. Deep vein thrombosis and pulmonary embolism are more common. It can also cause bradycardia and even total atrioventricular block. Rarely, it causes coronary artery spasm and even myocardial infarction. But almost simultaneous onset of myocardial infarction, third degree atrioventricular block and pulmonary embolism in one patient has not been reported so far.

Case presentation

A 53-year old man presented because of chest pain, nausea and then syncope for several minutes. Previous medical history included neurodermitis for which thalidomide was given and hypercholesterolemia with simvastatin taking. The patient didn’t exhibit any other established risk factors for coronary artery disease. Electrocardiography showed sinus rhythm with third degree atrioventricular block and complete right bundle branch block, and precordial leads ST segment elevation. The diagnosis of acute coronary syndrome was suspected, but further coronary angiography demonstrated no flow-limiting lesions in coronary arteries, and temporary pacemaker was implanted. After admission, low SpO₂ and elevated D-dimer level was mentioned. Further computed tomography pulmonary angiography revealed pulmonary embolism. Thalidomide was thought to be the cause of hypercoagulability and coronary spasm, so it was ceased immediately. Therapeutic low molecule weight heparin was initiated and then switched to warfarin with appropriate INR, and nifedipine was described for coronary spasm. The patient’s symptoms completely relived and SpO₂ recovered, and atrioventricular block had disappeared during hospitalization with pacemaker removed.

Conclusion

This is the very first case in which myocardial infarction, third degree atrioventricular block and pulmonary embolism almost simultaneously developed. We should be ware that anti-thrombotic prophylaxis, which needs further investigation for optimal drug and dosage, may be beneficial in thalidomide therapy. And it is also important to monitor patients taking thalidomide for signs and symptoms of bradycardia or higher degree atrioventricular block.

Prevalence of Myocardial Bridging in Patients With Myocardial Infarction and Nonobstructed Coronary Arteries

Mechanisms of acute myocardial infarction and nonobstructed coronary arteries (MINOCA) are incompletely understood. Myocardial bridging (MB) is usually considered a benign congenital variant, but serious complications have been reported. MB has also been proposed as a cause of takotsubo syndrome (TS). We aimed to examine whether MB was more frequent in patients with MINOCA or TS than in age- and gender-matched controls and to compare the MB detection rates of coronary computed tomography angiography (CTA) and invasive coronary angiography (ICA). Patients with MINOCA (n = 57) and age- and gender-matched controls (n = 58), aged 45 to 70 were enrolled. Myocarditis was excluded by cardiovascular magnetic resonance imaging. Patients with TS (n = 15) were considered as a subgroup and therefore not excluded. Patients with MINOCA underwent ICA and all study participants underwent coronary CTA. All examinations were reviewed with focus on MB. Among 57 MINOCA patients, 15 MINOCA patients with TS and 58 controls, MB was demonstrated in 28 patients (49%), 8 patients (53%), and 26 patients (45%), respectively. There were no statistically significant differences regarding the prevalence of MB or the type, location, length, or thickness of MB. There was a statistically significant difference (p <0.01) between the detection rates of coronary CTA and ICA that demonstrated MB in 54 subjects (47%) and 13 subjects (23%), respectively. In conclusion, MB was frequent with a similar prevalence in patients with MINOCA, patients with TS and controls. This suggests that there is no causal link between MB and MINOCA or TS. Furthermore, coronary CTA detects MB at a significantly higher rate than ICA.

[Acute coronary syndromes with ST elevation and angiographically normal culprit coronary arteries: Case report and update]

Acute coronary syndrome results in most cases of atherosclerotic plaque rupture. In a few cases, the physiopathological mechanism is different. This does not necessarily change the initial strategy but the subsequent treatments. We report three cases of clinical presentations of acute coronary syndrome whose pathophysiological mechanism is not or not mainly due to atherosclerotic lesions. Based on these cases and a review of the literature, two topics will be tackled: the diagnostic and therapeutic strategy in the management of Tako-tsubo cardiomyopathies and also acute coronary syndromes due to vasospastic angina.

Risk Factors and Markers for Acute Myocardial Infarction With Angiographically Normal Coronary Arteries

Myocardial Infarction with normal coronary arteries (MINCA) is common with a prevalence of 1% to 12% of all myocardial infarctions. The pathogenic mechanisms of MINCA are still unknown, but endothelial dysfunction has been suggested as a possible cause. To investigate risk factors and markers for MINCA, we conducted a case-control study. Considering the reported low prevalence of classical risk factors for coronary heart disease (CHD) in some but not all studies, our hypothesis was that endothelial function and intima-media thickness (IMT) were better, respectively lower, than CHD controls. One hundred patients with MINCA fulfilling diagnostic criteria according to the European Society of Cardiology/American Collage of Cardiology/American Heart Association universal definition of myocardial infarction with myocarditis excluded by cardiac magnetic resonance imaging were investigated. Risk factors, endothelial function (EndoPAT), and IMT were compared to gender- and age-matched patients with myocardial infarction and CHD, respectively healthy controls. Smoking, hypertension, impaired glucose tolerance and diabetes mellitus, inflammatory disease, and psychiatric disorders were more common in patients with MINCA than in healthy controls. In contrast to patients with CHD, the lipid profile was antiatherogenic with low low-density lipoprotein and high high-density lipoprotein cholesterol. There were no major differences between the groups regarding endothelial function and IMT that were in the normal range. In conclusion, the present study showed that MINCA was associated with many established cardiovascular risk factors without major differences in atherosclerosis markers. MINCA patients recalled a high prevalence of emotional stress before admission that together with previous psychiatric vulnerability and female gender speaks strongly in favor of Takotsubo syndrome being an important cause of MINCA.

The Role of Cardiac MRI in Patients with Troponin-Positive Chest Pain and Unobstructed Coronary Arteries

Acute coronary syndrome (ACS) still remains one of the leading causes of mortality and morbidity worldwide. Seven to fifteen percent of patients presenting with ACS have unobstructed coronary artery disease (CAD) on urgent angiography. Patients with ACS and unobstructed coronary arteries represent a clinical dilemma and their diagnosis and management is quite variable in current practice. Cardiovascular magnetic resonance imaging with its unique non-invasive myocardial tissue characterization property has the potential to identify underlying etiologies and reach a final diagnosis. These include acute and chronic myocarditis, embolic/spontaneous recanalization myocardial infarction, and Tako-Tsubo cardiomyopathy, and other conditions. Establishing a final diagnosis has a direct implication on patient's management and prognosis. In this article, we have reviewed the current evidence on the diagnostic role of cardiac magnetic resonance (CMR) in patients with ACS and unobstructed coronary arteries. We have also highlighted the potential role of CMR as a risk stratification or prognostication tool for this patient population.

Myocarditis or "true" infarction by cardiac magnetic resonance in patients with a clinical diagnosis of myocardial infarction without obstructive coronary disease: A meta-analysis of individual patient data

OBJECTIVE

Myocardial Infarction with Non-Obstructed Coronary Arteries (MINOCA) is common, but the causes are to a large extent unknown. Thus, we aimed to study the prevalence of myocarditis and "true" myocardial infarction determined by cardiac magnetic resonance (CMR) imaging in MINOCA patients, and risk markers for these two conditions in this population.

METHODS

A search was made in the PubMed and Cochrane databases using the search terms "Myocardial infarction", "Coronary angiography", "Normal coronary arteries" and "MRI". All relevant abstracts were read and seven of the studies fulfilled the inclusion criteria; studies describing case series of patients fulfilling the diagnosis of acute myocardial infarction with normal or non-obstructive coronary arteries on coronary angiography that were investigated with CMR imaging. Data from five of these studies are presented.

RESULTS

A total of 556 patients from 5 different sites were included. Fifty-one percent were men with a mean age of 52 ± 16 years. Thirty-three per cent of the patients had myocarditis (n = 183), whereas 21% of the patients had infarction on CMR (n = 115). Young age and a high CRP were associated with myocarditis whereas male sex, treated hyperlipidemia, high troponin ratio and low CRP were associated with "true" myocardial infarction.

CONCLUSION AND RELEVANCE

The results of this meta-analysis of individual data showed that myocarditis and "true" myocardial infarction are common in MINOCA when determined by CMR imaging. This information emphasizes the importance of performing CMR imaging in MINOCA patients and can be used clinically to guide diagnostics and treatment of MINOCA patients.

[Myocardial infarction and acute coronary syndrome: definitions, classification, and diagnostic criteria]

The review gives the definitions and classification of and diagnostic criteria for myocardial infarction and acute coronary syndrome in accordance with the "The third universal definition of myocardial infarction" adopted in 2012 (Joint ESC/ACCF/AHA/WHF Task Force for the Universal Definition of Myocardial Infarction, 2012). It also discusses the clinical and morphological comparisons of and the problems in the differential diagnosis of myocardial infarction as a nosological entity within coronary heart disease with other coronarogenic and non-coronarogenic necroses of the myocardium.

An uncommon complication of atrial fibrillation

Coronary embolism is a well-recognized cause of myocardial infarction. It is often under diagnosed and cardiologists need to be vigilant for this diagnosis. A 77-year-old man presented with chest pain with an ECG showing a new diagnosis of atrial fibrillation. Owing to ongoing chest pain coronary angiography was performed and revealed an acute occlusion of the left circumflex artery with coronary blood flow restored following aspiration of a large red thrombus. Following this the coronary vessel looked smooth with no residual coronary lesions requiring angioplasty or plaque rupture to justify the thrombosis. The clinical picture and angiographic data suggested the coronary embolus was secondary to the newly diagnosed atrial fibrillation.

The impact of smoking on long-term outcome of patients with premature (≤35years) ST-segment elevation acute myocardial infarction

BACKGROUND

There are few data regarding the long-term prognosis of young survivors of acute myocardial infarction (AMI). We explored the long-term outcome in individuals who had sustained a premature ST-segment elevation AMI.

METHODS

We recruited 257 consecutive patients who had survived their first AMI ≤35years of age. Patients were followed up for up to 18years. Clinical end points included all major adverse coronary events (MACE): cardiac death, readmission for acute coronary syndrome, arrhythmias, or coronary revascularization due to clinical deterioration.

RESULTS

The most prevalent risk factor at presentation was smoking (93.7%). Follow-up data were obtained from 237 patients (32.2±3.7years old). The median follow-up period was 9.1years. During follow-up, 139 (58.6%) patients reported continuation of smoking. Ninety-one (38.4%) patients had recurrent MACE (13 deaths, 59 acute coronary syndromes, 2 arrhythmias, and 17 revascularizations). Multivariable Cox regression analysis showed that persistence of smoking, left ventricular ejection fraction (LVEF), and reperfusion therapy (fibrinolysis or primary coronary angioplasty) were independent predictors of MACE after adjustment for conventional risk factors. Continuation of smoking remained an independent predictor for MACE after additional adjustments for LVEF (hazard ratio 2.154, 95% CI 1.313-3.535, P=.002) or reperfusion treatment (hazard ratio 2.327, 95% CI 1.423-3.804, P=.001). Harrell c statistic showed that the model with persistent smoking had the best discriminatory power compared with models with LVEF or reperfusion treatment.

CONCLUSIONS

In the era of statins and reperfusion treatment, continuation of smoking is the strongest independent long-term predictor for recurrent MACE in young survivors of premature AMI.

Diagnostic contribution of cardiac magnetic resonance in patients with acute coronary syndrome and culprit-free angiograms

BACKGROUND

In spite of robust knowledge about underlying ischemic myocardial damage, acute coronary syndromes (ACS) with culprit-free angiograms raise diagnostic concerns. The present study aimed to evaluate the additional value of cardiac magnetic resonance (CMR) over commonly available non-CMR standard tests, for the differentiation of myocardial injury in patients with ACS and non-obstructed coronary arteries.

MATERIAL/METHODS

Patients with ACS, elevated hs-TnT, and a culprit-free angiogram were prospectively enrolled into the study between January 2009 and July 2013. After initial evaluation with standard tests (ECG, echocardiography, hs-TnT) and provisional exclusion of acute myocardial infarction (AMI) in coronary angiogram, patients were referred for CMR with the suspicion of myocarditis or Takotsubo cardiomyopathy (TTC). According to the result of CMR, patients were reclassified as having myocarditis, AMI, TTC, or non-injured myocardium as assessed by late gadolinium enhancement.

RESULTS

Out of 5110 patients admitted with ACS, 75 had normal coronary angiograms and entered the study; 69 of them (92%) were suspected for myocarditis and 6 (8%) for TTC. After CMR, 49 patients were finally diagnosed with myocarditis (65%), 3 with TTC (4%), 7 with AMI (9%), and 16 (21%) with non-injured myocardium. The provisional diagnosis was changed or excluded in 23 patients (31%), with a 9% rate of unrecognized AMI.

CONCLUSIONS

The study results suggest that the evaluation of patients with ACS and culprit-free angiogram should be complemented by a CMR examination, if available, because the initial work-up with non-CMR tests leads to a significant proportion of misdiagnosed AMI.