Coronary Embolism: A Systematic Review

Coronary artery thromboembolism as a cause of myocardial infarction with non-obstructive coronary arteries (MINOCA)

Acute myocardial infarction (AMI) usually represents the clinical manifestation of atherothrombotic coronary artery disease (CAD) resulting from atherosclerotic plaque rupture. However, there are cases in which coronary angiography or coronary computed tomography angiography reveals patients with acute coronary syndrome with non-obstructive CAD. This clinical entity is defined as myocardial infarction with non-obstructive coronary arteries (MINOCA) and often is considered as a clinical dynamic working diagnosis, that needs further investigations for the establishment of a final etiological diagnosis. The main causes of a MINOCA working diagnosis include atherosclerotic, non-atherosclerotic (vessel-related and non-vessel related) and thromboembolic causes This literature review is aimed at investigating the major thromboembolic causes in patients presenting with MINOCA in regards of their etiology, pathophysiological mechanisms, as well as diagnostic and treatment methods.

Embolic myocardial infarction with cardiac arrest as an initial manifestation of non-bacterial thrombotic endocarditis

Non-bacterial thrombotic endocarditis, characterised by sterile vegetations, is commonly caused by systemic lupus erythematosus and is known to be complicated with embolic cerebrovascular disease. Embolic myocardial infarction with non-bacterial thrombotic endocarditis is extremely rare. We report a case of ventricular fibrillation arrest from presumed coronary embolisation in non-bacterial thrombotic endocarditis. While there are no standardised guidelines on the management of embolic myocardial infarction in endocarditis, it requires a multidisciplinary approach unique for every encountered clinical scenario.

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.

Acute Myocardial Infarction: Etiologies and Mimickers in Young Patients

Acute myocardial infarction is an important cause of death worldwide. While it often affects patients of older age, acute myocardial infarction is garnering more attention as a significant cause of morbidity and mortality among young patients (<45 years of age). More specifically, there is a focus on recognizing the unique etiologies for myocardial infarction in these younger patients as nonatherosclerotic etiologies occur more frequently in this population. As such, there is a potential for delayed and inaccurate diagnoses and treatments that can carry serious clinical implications. The understanding of acute myocardial infarction manifestations in young patients is evolving, but there remains a significant need for better strategies to rapidly diagnose, risk stratify, and manage such patients. This comprehensive review explores the various etiologies for acute myocardial infarction in young adults and outlines the approach to efficient diagnosis and management for these unique patient phenotypes.

Intravascular coronary lithotripsy for the treatment of iatrogenic calcium embolization: The "block and crack" technique

Intracoronary calcium embolization during percutaneous procedure is a very rare and unpredictable event, that  can lead to serious complications and even expert operators could face some technical issues to solve it. This case report presents a technique called "block and crack" used to manage iatrogenic intracoronary calcium embolization of left anterior descending coronary artery. The technique involves implanting a drug eluting stent (DES) to block the embolus against the vessel wall, followed by the use of lithotripsy balloon inflated inside the DES to crack the calcium and achieve a better stent expansion. This technique allowed to avoid further distal calcium embolization as well as to minimize residual stenosis degree after stent implantation.

Typical clinical presentation of acute myocardial infarction and confusing coronary angiography: A case report and literature review of coronary embolism

RATIONALE

The purpose of this article is to discuss the characteristics, diagnosis, treatment, and outcomes of cases of multiple coronary embolism (CE) highly suspected to be caused by a dislodged aneurysm of the ventricular membranous septum (AVMS) thrombus.

PATIENT CONCERNS

A 35-year-old man was rushed to the Chest Pain Center of Taicang TCM Hospital Affiliated to Nanjing University of Chinese Medicine for sudden onset of chest pain. The patient had severe and persistent chest pain without relief, accompanied by sweating throughout the body.

DIAGNOSIS

An electrocardiogram showed ST-segment elevation in the inferior wall leads, and blood tests suggested elevated troponin I levels. The initial diagnosis was acute ST-segment elevation myocardial infarction. Emergency coronary angiography revealed complete occlusion of the first diagonal branch, thrombolysis in myocardial infarction grade 0 flow, and smooth remaining vessels. Complete occlusion of the left anterior descending artery unexpectedly occurred during interventional treatment. Postoperative cardiac ultrasonography revealed the presence of a thrombus within the AVMS and in the apical portion of the heart. The final diagnosis was a CE.

INTERVENTIONS

Intraoperatively, the diagonal branch occluded segment was dilated with a balloon and intracoronary administration of tirofiban and nitroglycerin. Postoperatively, antithrombotic therapy (aspirin, clopidogrel, and rivaroxaban) was administered.

OUTCOMES

Ten days after admission, a repeat coronary angiography showed complete restoration of left anterior descending artery flow on its own, balloon dilation was again performed on the diagonal branch, and flow was restored to thrombolysis in myocardial infarction grade 1. Six months later, the intracardiac thrombus disappeared on repeat cardiac ultrasound.

LESSONS

AVMS is a potential source of embolism in patients with CE. CE has features that distinguish it from atherosclerosis, and a timely and correct diagnosis can help improve patient clinical outcomes.

Atrial Fibrillation Related Coronary Embolism: Diagnosis in the Focus

Atrial fibrillation (AF) is the most common arrhythmia in myocardial infarction (MI). AF can be caused by ischemia, and MI can be caused by AF. Additionally, 4-5% of MI cases are related to coronary embolism (CE), and one-third of cases are attributed to AF. Our aim was to investigate the prevalence of AF-related CE cases among 3 consecutive years of STEMI cases. We also aimed to reveal the diagnostic accuracy of the Shibata criteria scoring system and the role of thrombus aspiration. Among 1181 STEMI patients, 157 had AF (13.2%). By using the Shibata's diagnostic criteria, 10 cases were classified as 'definitive' and 31 as 'probable' CE. After re-evaluation, a further five cases were classified as 'definitive'. Further analysis of the 15 CE cases revealed that CE was more prevalent in patients with previously known (n = 10) compared to those with new-onset (n = 5) AF (16.7% vs. 5.1%, p = 0.024). A PubMed search was performed, and 40 AF-related cases were found where the Shibata's criteria could be applied. Further, 31 cases could be classified as 'definitive', 4 as 'probable' and, in 5 cases, the embolic origin could be excluded. In 40% of reported cases and in 47% of our cases, thrombus aspiration helped in diagnosis.

Case Report: A balloon-based technique to remove a pearl-like embolus out of the coronary artery

Coronary embolism is considered a rare non-atherosclerotic etiology of acute myocardial infarction, whereas atrial fibrillation is the main etiology of coronary embolism. We report a rare case of a patient with coronary embolism with a specific pearl-like embolus attributed to atrial fibrillation. For this patient, we used a balloon-based technique to successfully remove the embolus from the coronary artery.

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.

Advances in the available pharmacotherapy for the management of acute coronary syndromes in patients presenting without persistent ST-segment elevation

INTRODUCTION

Non-ST-segment elevation acute coronary syndromes (NSTE-ACS), including non-ST-segment-elevation myocardial infarction (NSTEMI) and unstable angina, represent a leading cause of mortality worldwide, with important socio-economic consequences. NSTEMI accounts for the majority of acute coronary syndromes and usually develops on the background of a nonocclusive thrombus. We searched for relevant literature in the field in PubMed and clinicaltrials.gov as of July 2022.

AREAS COVERED

A number of pharmacotherapies are currently available for treatment and secondary prevention, mainly including antithrombotic, lipid-lowering and anti-inflammatory drugs. Pretreatment with aspirin, anticoagulant and statin therapy is of key importance in the preprocedural phase, while pretreating with an oral P2Y12 inhibitor is not routinely indicated in patients undergoing early invasive management. For patients undergoing percutaneous coronary revascularization, pharmacotherapy essentially consists of antithrombotic drugs, which should be carefully selected. Finally, antithrombotic, lipid-lowering and anti-inflammatory drugs are important components of long-term secondary prevention after a NSTE-ACS.

EXPERT OPINION

This article reviews the evidence supporting recommendation on pharmacotherapy in patients presenting with a NSTE-ACS. Several randomized clinical trials are still ongoing and are expected to further inform scientific knowledge and clinical practice, with the final aim to improve the treatment of NSTE-ACS patients.

Diagnostic evaluation of unexplained ventricular tachyarrhythmias in younger adults

BACKGROUND

The diagnostic work-up for cardiac arrest from ventricular tachyarrhythmias occurring in younger adults and structurally normal hearts is variable and often incomplete.

METHODS

We reviewed records for all recipients of a secondary prevention implantable cardiac defibrillator (ICD) younger than 60 years at a single quaternary referral hospital from 2010 to 2021. Patients with unexplained ventricular arrhythmias (UVA) were identified as those with no structural heart disease on echocardiogram, no obstructive coronary disease, and no clear diagnostic features on ECG. We specifically evaluated the adoption rate of five modalities of "second-line" cardiac investigations: cardiac magnetic resonance imaging (CMR), exercise ECG, flecainide challenge, electrophysiology study (EPS), and genetic testing. We also evaluated patterns of antiarrhythmic drug therapy and device-detected arrhythmias and compared them with secondary prevention ICD recipients with a clear etiology found on initial assessment.

RESULTS

One hundred and two recipients of a secondary prevention ICD under the age of 60 were analyzed. Thirty-nine patients (38.2%) were identified with UVA and were compared with the remaining 63 patients with VA of clear etiology (61.8%). UVA patients were younger (35.6 ± 13.0 vs. 46.0 ± 8.6 years, p < .001) and were more often female (48.7% vs. 28.6%, p = .04). CMR was performed in 32 patients with UVA (82.1%), whereas flecainide challenge, stress ECG, genetic testing, and EPS were only performed in a minority of patients. Overall, the use of a second-line investigation suggested an etiology in 17 patients with UVA (43.5%). Compared to patients with VA of clear etiology, UVA patients had lower rates of antiarrhythmic drug prescription (64.1% vs. 88.9%, p = .003) and had a higher rate of device-delivered tachy-therapies (30.8% vs. 14.3%, p = .045).

CONCLUSION

In this real-world analysis of patients with UVA, the diagnostic work-up is often incomplete. While CMR was increasingly utilized at our institution, investigations for channelopathies and genetic causes appear to be underutilized. Implementation of a systematic protocol for work-up of these patients requires further study.

Acute myocardial infarction immediately after second vaccination for coronavirus disease 2019

We present a serious and rare case of acute myocardial infarction soon after the administration of second vaccination for coronavirus disease 2019. Patient's culprit lesion in the right coronary artery was identified and appropriately treated using intravascular imaging. Postvaccination monitoring of patients who are at high risk of cardiovascular diseases is critical.

Rare but severe cases of acute myocardial infarction following vaccination for coronavirus disease 2019 have been reported. Physicians should consider this rare side effect as a possible differential diagnosis and appropriately manage such patients.

Coagulation Disorders in Infective Endocarditis: Role of Pathogens, Biomarkers, Antithrombotic Therapy (Systematic Review)

The issue of antithrombotic therapy in patients with infective endocarditis has been studied for over 75 years. During that time studying of pathogenesis of the disease and its embolic complications, lead to the introduction of the concept of “immunothrombosis”. That mechanism allows infective agents (mostly bacteria) to be cloaked from the immune system and to multiply freely, leading to growth of vegetation, thus resulting in higher chance of fragmentation. Small-scale experimental and clinical studies on the correction of hemostatic disorders in infective endocarditis, that were performed in 20th century, didn’t show any significant results, that could affect clinical practice. However, reinterpretation of available data on coagulative system will allow to have elements of hemostasis as an application point in treating infective endocarditis. The article will discuss latest insights on the role of hemostasis system in pathophysisology of infective endocarditis, its effects on the development of the embolic complications, perspectives for diagnostics and treatment.

Rare Coronary Embolism Secondary to Cardioversion of Atrial Fibrillation

The diagnosis and management of myocardial infarction with nonobstructive coronary arteries (MINOCA) are difficult due to its variable presentations, different causes, and challenging diagnostic approaches. Cardiac imaging modalities including cardiac magnetic resonance (CMR) are very useful tools for diagnosing and managing MINOCA. Myocardial infarction (MI) can be caused by coronary emboli that can be contributed to atrial fibrillation (AF). Rarely, coronary embolism with resultant MINOCA can occur after direct current cardioversion (DCCV) even in fully anticoagulated patients. We present a rare case of a coronary embolism following DCCV as well as a CMR finding of microvascular obstruction (MVO), which has not previously been reported after DCCV. This case also emphasizes the value of obtaining a CMR for patients with MINOCA.

Double Delayed Enhancement: Concomitant Cardiac Amyloidosis and Acute Coronary Embolism

Hereditary cardiac amyloidosis (CA) is a relatively rare cause of nonischemic cardiomyopathy. The risk of intracardiac thrombi increases significantly in patients with CA. We report a case of a patient presenting with chest pain and acute myocardial infarction who was subsequently diagnosed with concomitant CA and acute coronary embolism.

Coronary Embolism despite CHA₂DS₂-VASc Score of Zero: Should We Reconsider Anticoagulation?

Coronary embolism (CE) is a rare but important cause of acute coronary syndrome. The most common source of emboli is considered to be infective endocarditis and atrial fibrillation. Various studies have estimated the prevalence of coronary embolism; however, diagnosis is challenging. Often, it is difficult to differentiate. Nonetheless, this is an important step as treating the underlying cause of an embolism is essential to limit recurrence. However, while this condition may have fatal consequences, due to its uncommon occurrence, there is no consensus on diagnosis and management. We present a case of a 53-year-old obese male, with a history of paroxysmal atrial fibrillation not on anticoagulation due to a low CHA₂DS₂-VASc score, who presented with chest pain associated with lightheadedness. ECG on admission revealed coarse atrial fibrillation, and troponin was gradually elevating on serial lab workup. Coronary angiography revealed a distal left anterior descending artery occlusion with apical wall akinesis without any evidence of atherosclerotic coronary artery disease. A presumptive diagnosis of coronary embolism secondary to paroxysmal atrial fibrillation was made, and the patient was started on anticoagulation despite a low CHA₂DS₂-VASc score. This case not only highlights coronary embolism but also illustrates that a low CHA₂DS₂-VASc score does not mean there is no risk of emboli. For such patients, it is important to take clinical reasoning into account along with the CHA₂DS₂-VASc score to determine the benefit of anticoagulation.

An unusual case of infective endocarditis with acute limb ischemia and cardiac embolism

Infective endocarditis (IE) is a persistent health issue, particularly among intravenous drug users. We discussed a case of infective endocarditis in a patient who uses IV drugs, which had some unusual features such as unusual presentation, polymicrobial infection, left-sided valve involvement, coronary embolism, and an uncommon pathogen for IE.

Risk factors for acute pulmonary embolism in patients with off-pump coronary artery bypass grafting: implications for nursing

Objective

Acute pulmonary embolism (APE) is a serious complication after off-pump coronary artery bypass grafting (OPCABG). We aimed to analyze the risk factors for APE in patients with OPCABG.

Methods

In this retrospective, observational study, patients with OPCABG who were treated in our hospital from 1 January 2018 to 31 March 2020 were included. The basic characteristics of patients and results of preoperative laboratory examinations were collected and analyzed.

Results

A total of 707 patients with OPCABG were included and the incidence of APE was 3.21%. Left ventricular ejection fraction (LVEF), a history of smoking, number of bypass grafting, duration of surgery, and age were significant risk factors for APE in patients with OPCABG. The areas under the curves of LVEF, number of bypass grafting, duration of surgery, and age were 0.773, 0.759, 0.738, and 0.723, respectively. The cutoff values of LVEF, number of bypass grafting, duration of surgery, and age were 59.84, 3.18, 237.42, and 73.28, respectively.

Conclusions

LVEF, a history of smoking, number of bypass grafting, duration of surgery, and age may be risk factors for APE in patients with OPCABG. Early measures should be taken to target these risks to prevent APE.

Prosthetic Aortic Valve Thrombosis Complicated by Left Main Coronary Artery Bifurcation Embolism: Case Report and Review of Literature

Coronary embolism due to prosthetic valve thrombosis is a rare cause of acute coronary syndrome. We report the challenging case of a 66-year-old female patient with non-ST-elevation myocardial infarction caused by left main coronary artery bifurcation embolism in the setting of mechanical aortic valve thrombosis. The patient was treated with intravenous thrombolysis. Four hours later, she suffered an anterior ST-elevation myocardial infarction due to left anterior descending artery embolization. Repeat coronary angiogram showed complete disappearance of the LMCA embolus with only distal LAD occlusion. The patient was further treated medically with excellent outcome.

Acute myocardial infarction caused by tumor embolus originating from upper tract urothelial carcinoma: a case report

Coronary emboli from malignant tumors rarely cause acute myocardial infarction. We report the case of a patient with tumor embolism from an upper tract urothelial carcinoma that caused acute myocardial infarction via a patent foramen ovale. Coronary blood flow was restored by embolus aspiration without stenting. Clinicians must consider malignant tumor embolism as a possible cause of acute myocardial infarction.