Mechanisms of Coronary Artery Spasm

Non-invasive imaging assessment in angina with non-obstructive coronary arteries (ANOCA)

Due to its significant prevalence and clinical implications, angina with non-obstructive coronary arteries (ANOCA) has become a major focus in modern cardiology. In fact, diagnosing ANOCA presents a significant challenge. The final diagnosis is often difficult, delayed, and frequently necessitates an invasive assessment through coronary angiography. However, recent improvements in non-invasive cardiac imaging allow a diagnosis of ANOCA using a combination of clinical evaluation, anatomical coronary imaging, and functional testing. This narrative review aims to critically assess various non-invasive diagnostic methods and propose a multimodal approach to diagnose ANOCA and tailor appropriate treatments.

Coronary Microvascular Dysfunction and Vasospastic Angina-Pathophysiology, Diagnosis and Management Strategies

Coronary artery disease is one of the leading public health problems in the world in terms of mortality and economic burden from the disease. Traditionally, the focus of research and clinical pathways leading to the diagnosis and treatment of coronary artery disease was on the more common variant of the disease resulting from atherosclerosis in the epicardial coronary arteries. However, coronary microvasculature, representing the vast majority of the total heart circulation, has the greatest influence on overall coronary resistance and, therefore, blood flow. Coronary microvascular dysfunction (CMD), characterized by structural or functional abnormalities in the microvasculature, significantly impacts myocardial perfusion. Endothelial dysfunction results in inadequate coronary dilation during exercise or spontaneous spasm in the microvasculature or epicardial arteries. A significant proportion of people presenting for coronary angiography in the context of angina have unobstructed epicardial coronary arteries yet are falsely reassured about the benign nature of their condition. Meanwhile, increasing evidence indicates that patients diagnosed with CMD as well as vasospastic angina (VSA) face an increased risk of Major Adverse Cardiovascular Events (MACEs), including death. The aim of this review is to outline the current practice with regard to invasive and non-invasive methods of CMD and VSA diagnosis and assess the evidence supporting the existing treatment strategies. These include endotype-specific pharmacological therapies, a holistic approach to lifestyle modifications and risk factor management and novel non-pharmacological therapies. Furthermore, the review highlights critical gaps in research and suggests potential areas for future investigation, to improve understanding and management of these conditions.

Ischemia during exercise stress testing, an indication of coronary vasomotor dysfunction?

Background

Recently it has been suggested that coronary microvascular dysfunction (CMD) may explain the high false-positive rate of exercise electrocardiographic stress testing (EST). However, patients with angina but non-obstructive coronary artery disease (ANOCA) present with a broader spectrum of coronary vasomotor dysfunction (CVDys), namely coronary artery spasm (CAS), CMD or a combination of both. We aim to investigate the diagnostic value of EST for the entire CVDys spectrum.

Methods

We included patients who underwent coronary function testing (CFT) in the Radboud University Medical Center. For each patient we requested the most recent EST report. ESTs were denoted as positive for ischemia if clinically significant ST-segment depression was detected. We calculated the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) with 95% confidence intervals for the diagnosis of CVDys and its endotypes.

Results

Of the 105 included patients (87 % women, mean age 57 (±8) years), 22 (21 %) had ischemia during EST. CVDys was diagnosed in 94 patients (90 %), of whom 58 patients had an isolated endotype (CAS: n = 51, CMD: n = 7) and 36 patients had CAS and CMD. Ischemia during EST yielded a high specificity and PPV for CVDys (specificity: 100 % (71.5-100 %), PPV: 100 % (84.6-100 %)), which remained reasonably similar for CAS (specificity: 94.4 % (72.7-99.9 %), PPV: 95.5 % (77.2-99.9 %)), but was lower for CMD (specificity: 85.5 % (74.2-93.1 %), PPV: 59.1 % (36.4-79.3 %)).

Conclusions

Ischemia during EST is highly specific for CVDys in general and can be an indicator for CAS and to a lesser extent for CMD in patients with ANOCA.

Known yet underdiagnosed: Invasive assessment of coronary microvascular disease and its implications

Coronary microvascular disease (CMD) is one of the commonest causes of cardiac chest pain. The condition is more prevalent in women, and incidence is known to increase with age, hypertension, and diabetes. The pathophysiological pathways are heterogenous and related to intrinsic vascular and endothelial dysfunction. Furthermore, this entity is known to be associated with adverse cardiovascular outcomes. Despite this, there is inertia amongst cardiologists to further evaluate patients with non-critical coronary artery disease and suspected CMD. With refinement in technology, we have now better understanding of CMD and invasive testing in the catheterization laboratory is a viable option for confirming the diagnosis of CMD. However, despite advances in diagnosing and stratifying this entity, therapeutic options remain limited and poorly defined. In this editorial, we will briefly focus on the pathophysiology and invasive assessment and therapeutic options available for CMD.

Stellate Ganglion Block and Bilateral Sympathectomy for Recurrent Coronary Vasospasm Secondary to Severe Eosinophilic Asthma

A 42-year-old man experienced recurrent coronary artery spasm (CAS) secondary to eosinophilic asthma despite being on multiple medications. He underwent a successful unilateral stellate ganglion block followed by bilateral thoracoscopic sympathectomy, with no subsequent recurrence of CAS. These invasive therapies offer a potential treatment option for refractory CAS.

Acute Coronary Syndrome in Women

Cardiovascular disease (CVD) is one of the leading causes of death in men and women throughout the world even after achieving advancement in the treatment and diagnosis. If considering patients in their old age, women tend to develop CVD later in life as compared to men as they are more likely to develop obesity and also diabetes. Recognizing the differences of sex in terms of acute coronary syndrome (ACS) and its management is very important for improving outcomes in women who present with ACS. This article reviews our current understanding of risk factors related to ACS and also its pathophysiology, management, and its outcomes in women.

Myocardial Infarction with Nonobstructive Coronary Artery Disease-Definition, Etiopathogenesis, Diagnosis, and Management

Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a complex clinical syndrome that is characterized by evidence of acute myocardial infarction in the absence of significant epicardial coronary artery disease on angiography. The term "MINOCA" encompasses a group of heterogeneous diseases with varying underlying mechanisms and each with its own pathophysiology. Overlooked plaque rupture or erosion and coronary vasospasm are the most common causes of MINOCA and can be diagnosed by routine intracoronary imaging and vasoreactivity testing, respectively. Coronary microvascular dysfunction is a less recognized, albeit an important cause of morbidity in patients presenting with MINOCA. Although MINOCA is a rare presentation of acute coronary syndrome, it is not a benign disorder and can have adverse consequences if untreated. In this article, we aim to review the pathogenesis, clinical characteristics, and finally propose a systematic approach in the diagnosis and management of patients with MINOCA.

Effects of statins in patients with coronary artery spasm: A nationwide population-based study

Controversies regarding the benefits of statin treatment on clinical outcomes in coronary artery spasm (CAS) without obstructive coronary artery disease (CAD) persist due to limited data. In this retrospective nationwide population-based cohort study from the Taiwan National Health Insurance Research Database during the period 2000-2012, the matched cohorts consisted of 12,000 patients with CAS. After propensity score matching with 1:1 ratio, 2216 patients were eligible for outcome analysis in either statin or nonstatin group, with the mean follow-up duration of 4.8 and 4.6 years, respectively. Statin users versus nonusers had a significantly reduced risk of major adverse cardiovascular events (MACEs) (6.7% vs. 9.5%, hazard ratio [HR] 0.68; 95% confidence interval [CI] 0.55-0.84) and all-cause mortality (6.0% vs. 7.6%; HR 0.77; 95% CI 0.61-0.96). While the results of MACEs were mainly contributed by cardiovascular death (1.9% vs. 3.2%; HR 0.56; 95% CI 0.38-0.83) and ischemic stroke (3.8% vs. 5.4%; subdistribution HR 0.69; 95% CI 0.52-0.91), they were primarily driven by reductions in ischemic but not hemorrhagic stroke. The benefit of statins was significantly pronounced in patients with hypertension and diabetes. Nevertheless, the effect on MACEs was consistent irrespective of age, sex, dyslipidemia, and mental disorder. Statins significantly reduced the risk of MACEs and all-cause mortality in CAS patients. The benefit of statin therapy in reducing MACEs appeared to be linear, with greater risk reduction with higher doses and longer duration without upper threshold, reflecting the dose-dependent relationship of statins with MACEs in CAS patients.

Coronary Microvascular Dysfunction: Searching the Strongest Imaging Modality in Different Scenarios

Coronary microvascular dysfunction is a clinical condition very diffuse in many different settings. Often the diagnosis can be very tricky, and choosing the proper diagnostic strategy can be fundamental for reaching the goal. The aim of this review is to evaluate the properties and the feasibility of our tests in specific scenarios by looking at the performances of each methodology reported in the literature.

MINOCA: A Pathophysiological Approach of Diagnosis and Treatment-A Narrative Review

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a clinical entity characterized by the absence of significant coronary artery obstruction in epicardial arteries (<50%) on coronary angiography in the setting of acute myocardial infarction (AMI). This article aims to provide a narrative review of the pathophysiological mechanisms, diagnostic challenges, and prognosis associated with MINOCA based on pathophysiology regarding the atherosclerotic and non-atherosclerotic causes. Etiological factors, including thromboembolism, coronary artery spasm, spontaneous coronary artery dissection, coronary microvascular disease, and supply-demand mismatch, are addressed. Imaging modalities such as echocardiography, advances in coronary angiography like intravascular ultrasound (IVUS) and optical coherence tomography (OCT), cardiac magnetic resonance (CMR), and coronary computed tomography angiography (CCTA) are also analyzed. MINOCA patients have a better short-term prognosis compared to those with obstructive coronary artery disease but face significant long-term risks, underscoring the need for precise diagnosis and management strategies. Elevated inflammatory markers and specific genetic predispositions are also associated with adverse outcomes in MINOCA. This review focused on MINOCA from a pathophysiological perspective on the diverse underlying mechanisms, the challenges in achieving accurate diagnosis, the importance of a tailored therapeutic approach and the necessity for further investigation of clinical outcomes.

Absolute coronary blood flow across different endotypes of ANOCA

BACKGROUND

Intracoronary continuous thermodilution is a novel technique to quantify absolute true coronary flow and microvascular resistance. However, few data are available in patients with angina with non-obstructive coronary arteries (ANOCA).

AIMS

This study aimed to investigate the diagnostic potential of hyperaemic absolute coronary flow (Qmax) and absolute microvascular resistance (Rμ,hyper) among different ANOCA endotypes, and to determine the correlation between continuous - and bolus - thermodilution indexes.

METHODS

A total of 222 patients were scheduled for clinically indicated coronary function testing (CFT), of whom 120 patients were included in this analysis. These patients underwent CFT including acetylcholine (ACh) provocation testing and microvascular function assessment using both bolus and continuous thermodilution.

RESULTS

CFT was negative (CFT-) in 32 (26.7%) patients. Endothelium-dependent dysfunction (ACh+) was present in 63 (52.5%) patients, and coronary microvascular dysfunction (CMD) identified at bolus thermodilution (CMD+) was present in 62 (51.7%) patients. Patients with a positive CFT (CFT+) showed significantly lower Qmax and higher Rμ,hyper values as compared to CFT-. Qmax was significantly lower in CMD+ versus CMD- patients (0.174 vs 0.222 L/min; p=0.04) but did not differ in patients with or without a positive ACh test (0.198 vs 0.219 L/min; p=0.86).

CONCLUSIONS

The prevalence of a CFT+ is high in a selected ANOCA population. In our study, Qmax and Rμ,hyper were associated with a positive CFT. Qmax was associated with the presence of microvascular dysfunction but not with a positive acetylcholine test. The novel continuous thermodilution method can provide further insights into ANOCA endotypes.

Acute coronary syndrome due to coronary vasospasm: a case report

Coronary vasospasm can lead to decreased cardiac perfusion and result in acute coronary syndrome. Here is a case of a 49-year-old man presented to the emergency department with epigastric pain and nausea with normal initial electrocardiogram. However, 6 h later, the patient experienced severe chest pain prompting a repeat electrocardiogram demonstrating inferior ST-segment elevation with troponin I levels peaked at 1.2 ng/ml (normal range: 0.00-0.02 ng/ml). Coronary angiography revealed angiographic stenosis in the left circumflex territory of a left dominant system which resolved with intracoronary nitroglycerin administration indicating ischemia with nonobstructive coronary arteries secondary to coronary vasospasm. He was discharged on isosorbide mononitrate and amlodipine therapy and had no recurrence of symptoms during follow-up.

Ischemia with non-obstructive coronary artery (INOCA): Non-invasive versus invasive techniques for diagnosis and the role of #FullPhysiology

Ischemia with non-obstructive coronary arteries (INOCA) is an increasingly recognized entity. It encompasses different pathophysiological subtypes (i.e., endotypes), including coronary microvascular dysfunction (CMD), vasospastic angina (VSA) and mixed entities resulting from the variable combination of both. Diagnosing INOCA and precisely characterizing the endotype allows for accurate medical treatment and has proven prognostic implications. A breadth of diagnostic technique is available, ranging from non-invasive approaches to invasive coronary angiography adjuvated by functional assessment and provocative tests. This review summarizes the strength and limitations of these methodologies and provides the rationale for the routine referral for invasive angiography and functional assessment in this subset of patients.

Coronary Microvascular Dysfunction: A Guide for Clinicians

Dysfunction of the coronary microvasculature has become increasingly recognized as an important mechanism of myocardial ischemia in patients without obstructive coronary artery disease. The causes and management of coronary microvascular dysfunction remain poorly understood and are still largely based on extrapolation of epicardial coronary artery disease data. Quantification of myocardial blood flow and flow reserve have improved diagnosis, though important questions remain. In this review, we explain current understanding of the spectrum of pathophysiology of coronary microvascular dysfunction, summarize current diagnostic techniques to assess for coronary microvascular dysfunction, and appraise the limited data on management options specifically for patients with coronary microvascular dysfunction.

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

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

Hypocapnia is associated with increased in-hospital mortality and 1 year mortality in acute heart failure patients

AIMS

Both hypercapnia and hypocapnia are common in patients with acute heart failure (AHF), but the association between partial pressure of arterial carbon dioxide (PaCO2) and AHF prognosis remains unclear. The objective of this study was to investigate the connection between PaCO2 within 24 h after admission to the intensive care unit (ICU) and mortality during hospitalization and at 1 year in AHF patients.

METHODS AND RESULTS

AHF patients were enrolled from the Medical Information Mart for Intensive Care IV database. The patients were divided into three groups by PaCO2 values of <35, 35-45, and >45 mmHg. The primary outcome was to investigate the connection between PaCO2 and in-hospital mortality and 1 year mortality in AHF patients. The secondary outcome was to assess the prediction value of PaCO2 in predicting in-hospital mortality and 1 year mortality in AHF patients. A total of 2374 patients were included in this study, including 457 patients in the PaCO2 < 35 mmHg group, 1072 patients in the PaCO2 = 35-45 mmHg group, and 845 patients in the PaCO2 > 45 mmHg group. The in-hospital mortality was 19.5%, and the 1 year mortality was 23.9% in the PaCO2 < 35 mmHg group. Multivariate logistic regression analysis showed that the PaCO2 < 35 mmHg group was associated with an increased risk of in-hospital mortality [hazard ratio (HR) 1.398, 95% confidence interval (CI) 1.039-1.882, P = 0.027] and 1 year mortality (HR 1.327, 95% CI 1.020-1.728, P = 0.035) than the PaCO2 = 35-45 mmHg group. The PaCO2 > 45 mmHg group was associated with an increased risk of in-hospital mortality (HR 1.387, 95% CI 1.050-1.832, P = 0.021); the 1 year mortality showed no significant difference (HR 1.286, 95% CI 0.995-1.662, P = 0.055) compared with the PaCO2 = 35-45 mmHg group. The Kaplan-Meier survival curves showed that the PaCO2 < 35 mmHg group had a significantly lower 1 year survival rate. The area under the receiver operating characteristic curve for predicting in-hospital mortality was 0.591 (95% CI 0.526-0.656), and the 1 year mortality was 0.566 (95% CI 0.505-0.627) in the PaCO2 < 35 mmHg group.

CONCLUSIONS

In AHF patients, hypocapnia within 24 h after admission to the ICU was associated with increased in-hospital mortality and 1 year mortality. However, the increase in 1 year mortality may be influenced by hospitalization mortality. Hypercapnia was associated with increased in-hospital mortality.

Axillary and subclavian venous spasm during pacemaker implantation - A case report and literature review

Key Clinical Message

Venous spasm is an important reason for complicated or failed implantations of cardiac implantable electronic devices. Prevention or risk reduction of venous spasm during cardiac implantable electronic device implantation may be achieved by ultrasound or fluoroscopic imaging prior to puncture, cephalic vein cut-down, sufficient pre- and perioperative hydration, nitroglycerin injection and effective sedation, and analgesia.

Abstract

This case report with literature review focuses on venous spasm as a potential cause for complicated implantations of cardiac implantable electronic devices. The case report is clinically relevant as it describes a progressive spasm affecting the axillary and the subclavian vein. A 66-year-old female complained of symptomatic atrial fibrillation (AF) and atypical atrial flutter despite interventional and medical treatment. As an ultimate treatment, she was scheduled for pacemaker implantation and atrioventricular node ablation. Several puncture attempts of the axillary vein failed. Despite venous blood aspiration, no guidewires could be advanced into the axillary vein. We performed a first venogram revealing significant spasm of the axillary vein. Another failed venous puncture occurred after change of access site to the subclavian vein. A second venogram displayed progression of the spasm, now affecting both the axillary and the subclavian veins. Normal saline perfusion was administered as well as intravenous isosorbide. Unfortunately, a repeated venogram after 15 min waiting time showed persistence of the spasm, still affecting both veins. The procedure was discontinued as the patient became uncomfortable. Venous spasm is an important reason for complicated or failed implantations of cardiac implantable electronic devices. Commonly used medical prevention and treatment are intravenous fluids and nitroglycerin. Prevention or risk reduction of venous spasm during cardiac implantable electronic device implantation may be achieved by ultrasound or fluoroscopic imaging prior to puncture, cephalic vein cut-down, sufficient pre- and perioperative hydration, nitroglycerin injection and effective sedation and analgesia.

Psychological burden in patients with angina and unobstructed coronary arteries-underestimated, underexplored, undertreated

Patients with angina and unobstructed coronary arteries (ANOCA) are frequently encountered in clinical practice. These cases represent a diagnostic and therapeutic challenge and are often characterized by a long patient journey until a diagnosis of coronary vasomotor disorders is established. Moreover, the unsatisfactory management of such patients leads to insecurity, ongoing symptoms, and psychological sequelae such as anxiety or depression. Currently, the psychological burden in patients with ANOCA is underestimated, underexplored, and undertreated. This review gives a new perspective on the pathophysiology of coronary vasomotor disorders including psychological risk factors and calls for comprehensive care by interdisciplinary ANOCA clinics.

MI and Non-obstructive Coronary Arteries

MI and non-obstructive coronary arteries (MINOCA) is recognized as an important contributor to adverse cardiovascular outcomes in both men and women but is particularly prevalent in young women. Multiple coronary mechanisms such as coronary plaque disruption, coronary artery spasm, coronary microvascular dysfunction, spontaneous coronary artery dissection, and coronary thromboembolism can trigger MINOCA. Beyond routine left heart catheterization, invasive intracoronary imaging and cardiac MRI can help to clarify the cause of MINOCA. Conditions such as myocarditis, takotsubo syndrome, and cardiomyopathy are on the differential as alternate explanations in those suspected of MINOCA. Identification of the underlying cause in a case of MINOCA has therapeutic implications. While long-term management of MINOCA is not standardized, angiotensin converting enzyme inhibitors and statins appear to be of benefit. In this review, we discuss the prevalence and pathophysiology of MINOCA, diagnostic considerations, and current treatment approaches to manage this high-risk group of patients.

Severe ST-segment elevation and AV block during pulsed-field ablation due to vasospastic angina - a novel observation

Catheter ablation of atrial fibrillation using non-thermal electroporation represents a promising ablation modality due to its believed superior safety profile. Still, if electroporation is delivered in proximity to a coronary artery, vasospasms can occur. We report the first case of severe right coronary artery vasospasm resulting in ST-segment elevation and AV block despite a remote distance from the ablation site to the right coronary artery, indicating a different mechanism. In this case, electroporation most likely triggered a previously unknown Prinzmetal vasospastic angina in the patient, resulting in the coronary vasospasm. Thus, meticulous monitoring of ST-segment changes following PFA delivery even from regions remote to coronary arteries is required.

Optimal Medical Therapy for Stable Ischemic Heart Disease: Focus on Anti-anginal Therapy

Chronic coronary disease (CCD) is a major cause of morbidity and mortality worldwide. The most common symptom of CCD is exertional angina pectoris, a discomfort in the chest that commonly occurs during activities of daily life. Patients are dismayed by recurring episodes of angina and seek medical help in preventing or minimizing episodes. Angina occurs when the coronary arteries are unable to supply sufficient blood flow to the cardiac muscle to meet the metabolic needs of the left ventricular myocardium. While lifestyle changes and aggressive risk factor modification play a critical role in the management of CCD, management of angina usually requires pharmacologic therapy. Medications such as beta-blockers, calcium channel blockers, nitrates, ranolazine, and others ultimately work to improve the mismatch between myocardial blood flow and metabolic demand. This manuscript briefly describes the pathophysiologic basis for symptoms of angina, and how currently available anti-anginal therapies contribute to preventing or minimize the occurrence of angina.

Ischaemic heart disease in patients with cancer

Cardiologists are encountering a growing number of cancer patients with ischaemic heart disease (IHD). Several factors account for the interrelationship between these two conditions, in addition to improving survival rates in the cancer population. Established cardiovascular (CV) risk factors, such as hypercholesterolaemia and obesity, predispose to both IHD and cancer, through specific mechanisms and via low-grade, systemic inflammation. This latter is also fuelled by clonal haematopoiesis of indeterminate potential. Furthermore, experimental work indicates that IHD and cancer can promote one another, and the CV or metabolic toxicity of anticancer therapies can lead to IHD. The connections between IHD and cancer are reinforced by social determinants of health, non-medical factors that modify health outcomes and comprise individual and societal domains, including economic stability, educational and healthcare access and quality, neighbourhood and built environment, and social and community context. Management of IHD in cancer patients is often challenging, due to atypical presentation, increased bleeding and ischaemic risk, and worse outcomes as compared to patients without cancer. The decision to proceed with coronary revascularization and the choice of antithrombotic therapy can be difficult, particularly in patients with chronic coronary syndromes, necessitating multidisciplinary discussion that considers both general guidelines and specific features on a case by case basis. Randomized controlled trial evidence in cancer patients is very limited and there is urgent need for more data to inform clinical practice. Therefore, coexistence of IHD and cancer raises important scientific and practical questions that call for collaborative efforts from the cardio-oncology, cardiology, and oncology communities.

To Repair a Broken Heart: Stem Cells in Ischemic Heart Disease

Despite improvements in contemporary medical and surgical therapies, cardiovascular disease (CVD) remains a significant cause of worldwide morbidity and mortality; more specifically, ischemic heart disease (IHD) may affect individuals as young as 20 years old. Typically managed with guideline-directed medical therapy, interventional or surgical methods, the incurred cardiomyocyte loss is not always completely reversible; however, recent research into various stem cell (SC) populations has highlighted their potential for the treatment and perhaps regeneration of injured cardiac tissue, either directly through cellular replacement or indirectly through local paracrine effects. Different stem cell (SC) types have been employed in studies of infarcted myocardium, both in animal models of myocardial infarction (MI) as well as in clinical studies of MI patients, including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), Muse cells, multipotent stem cells such as bone marrow-derived cells, mesenchymal stem cells (MSCs) and cardiac stem and progenitor cells (CSC/CPCs). These have been delivered as is, in the form of cell therapies, or have been used to generate tissue-engineered (TE) constructs with variable results. In this text, we sought to perform a narrative review of experimental and clinical studies employing various stem cells (SC) for the treatment of infarcted myocardium within the last two decades, with an emphasis on therapies administered through thoracic incision or through percutaneous coronary interventions (PCI), to elucidate possible mechanisms of action and therapeutic effects of such cell therapies when employed in a surgical or interventional manner.

Phosphorylated CPI-17 and MLC2 as Biomarkers of Coronary Artery Spasm-Induced Sudden Cardiac Death

Coronary artery spasm (CAS) plays an important role in the pathogeneses of various ischemic heart diseases and has gradually become a common cause of life-threatening arrhythmia. The specific molecular mechanism of CAS has not been fully elucidated, nor are there any specific diagnostic markers for the condition. Therefore, this study aimed to examine the specific molecular mechanism underlying CAS, and screen for potential diagnostic markers. To this end, we successfully constructed a rat CAS model and achieved in vitro culture of a human coronary-artery smooth-muscle cell (hCASMC) contraction model. Possible molecular mechanisms by which protein kinase C (PKC) regulated CAS through the C kinase-potentiated protein phosphatase 1 inhibitor of 17 kDa (CPI-17)/myosin II regulatory light chain (MLC2) pathway were studied in vivo and in vitro to screen for potential molecular markers of CAS. We performed hematoxylin and eosin staining, myocardial zymogram, and transmission electron microscopy to determine myocardial and coronary artery injury in CAS rats. Then, using immunohistochemical staining, immunofluorescence staining, and Western blotting, we further demonstrated a potential molecular mechanism by which PKC regulated CAS via the CPI-17/MLC2 pathway. The results showed that membrane translocation of PKCα occurred in the coronary arteries of CAS rats. CPI-17/MLC2 signaling was observably activated in coronary arteries undergoing CAS. In addition, in vitro treatment of hCASMCs with angiotensin II (Ang II) increased PKCα membrane translocation while consistently activating CPI-17/MLC2 signaling. Conversely, GF-109203X and calphostin C, specific inhibitors of PKC, inactivated CPI-17/MLC2 signaling. We also collected the coronary artery tissues from deceased subjects suspected to have died of CAS and measured their levels of phosphorylated CPI-17 (p-CPI-17) and MLC2 (p-MLC2). Immunohistochemical staining was positive for p-CPI-17 and p-MLC2 in the tissues of these subjects. These findings suggest that PKCα induced CAS through the CPI-17/MLC2 pathway; therefore, p-CPI-17 and p-MLC2 could be used as potential markers for CAS. Our data provide novel evidence that therapeutic strategies against PKC or CPI-17/MLC2 signaling might be promising in the treatment of CAS.

Cancer and arterial thrombosis: therapeutic options

A State of the Art lecture titled "Cancer and Arterial Thrombosis: Therapeutic Options" was presented at the International Society on Thrombosis and Haemostasis Congress in 2023. This State of the Art review delves into the complex relationship between cancer and arterial thromboembolism (ATE), encompassing acute coronary syndrome, ischemic strokes, and peripheral arterial disease. The burden of cancer-associated ATE is not well defined, but studies indicate elevated risks, particularly in the 6 months after a cancer diagnosis. Incidence varies among cancer subtypes, with lung cancer displaying the highest rates. Additionally, the pathophysiology of cancer-associated ATE involves a multifaceted interplay of cancer-induced hypercoagulopathy, cancer therapy-related thrombosis, and personal risk factor contributors. ATEs are clinically heterogeneous and in the context of cancer have particular mechanistic differences compared with ATE patients without cancer. This requires modifications in approach and tailored management considerations. Specific etiologies contributing to ATE, such as coronary vasospasm and non-bacterial-thrombotic endocarditis, need to be considered. The diagnosis of cancer alone usually does not contraindicate patients to standard guideline-based therapies for the management of ATE, although nuances in treatment may need to be considered in light of the underlying cancer. Atrial fibrillation in cancer patients further complicates the thrombotic landscape. Cancer patients with atrial fibrillation are at a higher risk of ATE, necessitating careful consideration of anticoagulation therapy as clinical benefits and bleeding risks need to be weighed. ATE may also be a presenting sign of underlying malignancy, which requires increased awareness and focused clinical evaluation for cancer in selected cases. Finally, we summarize relevant new data on this topic presented during the 2023 International Society on Thrombosis and Haemostasis Congress.

Capecitabine-induced-coronary-vasospasm leading to polymorphic ventricular tachycardia and cardiac arrest

Capecitabine, a pro-drug of 5-fluorouracil, is commonly used in the treatment of breast and colorectal cancer. Its side effects, including nausea, vomiting, diarrhea, fatigue, loss of appetite, and bone marrow suppression, are well recognized. However, coronary vasospasm represents a less commonly recognized but significant complication of fluoropyrimidine-based therapies such as capecitabine. Proposed mechanisms for this adverse effect complication include direct endothelium-independent vasoconstriction, activation of protein kinase C, and activation of the cyclooxygenase pathway. In this report, we present a case of capecitabine-induced coronary vasospasm leading to progressive, focal ST-elevations, myocardial ischemia, and subsequently polymorphic ventricular tachycardia. These events were captured on telemetry, in a male in his early 40s, diagnosed with stage IIIB sigmoid colon cancer. Notably, the patient had no pre-existing coronary artery disease or other cardiovascular risk factors. Upon diagnosis, the patient was initiated on a calcium channel blocker, verapamil, to mitigate further coronary vasospasm events. After thorough discussions that prioritized the patient's input and values, an implantable cardioverter-defibrillator was placed subcutaneously. Following discharge, the patient restarted capecitabine therapy along with verapamil prophylaxis and did not experience any subsequent shocks from his ICD as assessed during his outpatient follow-up visits. This case emphasizes the need to involve patients in decision-making processes, especially when managing unexpected and serious complications, to ensure treatments align with their quality of life and personal preferences.

Acute Myocardial Infarction in Pregnancy

Pregnancy-associated myocardial infarction is an overall uncommon event, but can be associated with significant maternal and fetal morbidity and mortality. In contrast to myocardial infarction in the general nonpregnant population, the mechanism of pregnancy-associated myocardial infarction is most commonly due to nonatherosclerotic mechanisms such as coronary dissection, vasospasm, or thromboembolism. The diagnosis of pregnancy-associated myocardial infarction can be challenging, requiring a high index of suspicion for prompt recognition and management. Furthermore, the management of pregnancy-associated myocardial infarction can be complex due to maternal and fetal considerations and may vary based on the specific underlying mechanism of the myocardial infarction. This review aims to review the recent literature on pregnancy-associated myocardial infarction and summarize the epidemiology, mechanisms, diagnosis, and treatment strategies for this uncommon entity.

Pathophysiology of Myocardial Infarction With Nonobstructive Coronary Artery Disease: A Contemporary Systematic Review

Background

Myocardial infarction with nonobstructive coronary artery disease (MINOCA) is defined as acute myocardial infarction (AMI) with angiographically nonobstructive coronary artery disease. MINOCA represents 6% of all AMI cases and is associated with increased mortality and morbidity. However, the wide array of pathophysiological factors and causes associated with MINOCA presents a diagnostic conundrum. Therefore, we conducted a contemporary systematic review of the pathophysiology of MINOCA.

Methods

A comprehensive systematic review of MINOCA was carried out through the utilization of the PubMed database. All systematic reviews, meta-analyses, randomized controlled trials, and cohort studies available in English or French that reported on the pathophysiology of MINOCA published after January 1, 2013 were retained.

Results

Of the 600 identified records, 80 records were retained. Central to the concept of MINOCA is the definition of AMI, characterized by the presence of myocardial damage reflected by elevated cardiac biomarkers in the setting of acute myocardial ischemia. As a result, a structured approach should be adopted to thoroughly assess and address clinically overlooked obstructive coronary artery disease, and cardiac and extracardiac mechanisms of myocyte injury. Once these options have been ruled out, a diagnosis of MINOCA can be established, and the appropriate multimodal assessment can be conducted to determine its specific underlying cause (plaque disruption, epicardial coronary vasospasm, coronary microvascular dysfunction, and coronary embolism and/or spontaneous coronary dissection or supply-demand mismatch).

Conclusions

Integrating a suitable definition of AMI and understanding the pathophysiological mechanisms of MINOCA are crucial to ensure an effective multimodal diagnostic evaluation and the provision of adequate tailored therapies.

Multimodality imaging approach in a case of vascular toxicity caused by cabozantinib

Vascular toxicity caused by cancer treatment can present as vasospasm, arterial thrombosis, and accelerated atherosclerosis. We report a case of a 60-year-old man with metastatic renal cell carcinoma under cabozantinib treatment for 3 years who presented to the hospital with relapsing episodes of rest angina. Due to the presence of ST depression in the 12-lead electrocardiogram and elevated troponin, a non-ST-segment elevation myocardial infarction was suspected. The patient underwent invasive coronary angiography, which revealed extended coronary artery spasm, and it subsided totally after nitrate administration. One year later, the patient presented again at the cardio-oncology outpatient clinic, reporting relapsing episodes of angina during the previous month. Coronary computed tomography angiography was performed, and it revealed 2 subsequent 70%-99% stenosis in OM1. To our knowledge, this is the first case of a patient treated with cabozantinib presenting with coronary artery spasm and accelerated atherosclerosis, in which a multimodality imaging approach was followed.

Life-threatening coronary vasospasm in patients with type 2 diabetes with SGLT2 inhibitor-induced euglycemic ketoacidosis: a report of two consecutive cases

Euglycemic diabetic ketoacidosis (eDKA) has emerged as an adverse event associated with sodium-glucose transporter-2 inhibitors (SGLT2i). We present two consecutive cases of SGLT2i-induced eDKA, both manifested as life-threatening coronary vasospastic angina (VSA). Case 1: A 64-year-old male overweight patient with type 2 diabetes (BMI 28.2 kg/m2), treated with dapagliflozin 5 mg daily for 6 months and a restricted diet for 2 months, experienced loss of consciousness following severe chest pain while driving, resulting in a traffic accident: plasma glucose, 163 mg/dL; urine ketones, (+++); bicarbonate (HCO3-), 13.2 mmol/L; and total ketone body, 1539 µmol/L. Coronary angiography (CAG) performed on day 5 revealed diffusely spastic coronary arteries with 90% stenosis in the right coronary artery, leading to the diagnosis of VSA in the presence of coronary atherosclerosis. Case 2: A 63-year-old male patient with type 2 diabetes (BMI 22.2 kg/m2) experienced severe chest discomfort and faintness following 2 months of chest pain while on dapagliflozin 10 mg daily for 1 year: plasma glucose, 112 mg/dL; urine ketones, (+++); HCO3-, 15.3 mmol/L; and total ketone body, 10,883 µmol/L. CAG performed on day 10 revealed no organic stenosis but diffusely spastic coronary arteries in response to coronary ergonovine infusion, confirming the diagnosis of VSA. SGLT2i has the potential to inhibit acetylcholine and butyrylcholine esterase activities, leading to reduced scavenging of acetylcholine and possible induction of coronary vasospasm. These cases highlight the association between life-threatening VSA and SGLT2i-induced eDKA.

Vasospastic angina: a review on diagnostic approach and management

Vasospastic angina (VSA) refers to chest pain experienced as a consequence of myocardial ischaemia caused by epicardial coronary spasm, a sudden narrowing of the vessels responsible for an inadequate supply of blood and oxygen. Coronary artery spasm is a heterogeneous phenomenon that can occur in patients with non-obstructive coronary arteries and obstructive coronary artery disease, with transient spasm causing chest pain and persistent spasm potentially leading to acute myocardial infarction (MI). VSA was originally described as Prinzmetal angina or variant angina, classically presenting at rest, unlike most cases of angina (though in some patients, vasospasm may be triggered by exertion, emotional, mental or physical stress), and associated with transient electrocardiographic changes (transient ST-segment elevation, depression and/or T-wave changes). Ischaemia with non-obstructive coronary arteries (INOCA) is not a benign condition, as patients are at elevated risk of cardiovascular events including acute coronary syndrome, hospitalization due to heart failure, stroke and repeat cardiovascular procedures. INOCA patients also experience impaired quality of life and associated increased healthcare costs. VSA, an endotype of INOCA, is associated with major adverse events, including sudden cardiac death, acute MI and syncope, necessitating the study of the most effective treatment options currently available. The present literature review aims to summarize current data relating to the diagnosis and management of VSA and provide details on the sequence that treatment should follow.

Familial risk of vasospastic angina: a nationwide family study in Sweden

OBJECTIVES

Vasospastic angina (VSA) is a complex coronary vasomotor disorder associated with an increased risk of myocardial infarction and sudden death. Despite considerable advances in understanding VSA pathophysiology, the interplay between genetic and environmental factors remains elusive. Accordingly, we aimed to determine the familial VSA risk among first-degree relatives of affected individuals.

METHODS

A population-based multigenerational cohort study was conducted, including full-sibling pairs born to Swedish parents between 1932 and 2018. Register-based diagnoses were ascertained through linkage to the Swedish Multigeneration Register and National Patient Register. Incidence rate ratios (IRRs) and adjusted HRs were calculated for relatives of individuals with VSA compared with relatives of individuals without VSA.

RESULTS

The total study population included 5 764 770 individuals. Overall, 3461 (0.06%) individuals (median age at disease onset 59 years, IQR: 63-76) were diagnosed with VSA. Of these, 2236 (64.61%) were women. The incidence rate of VSA for individuals with an affected sibling was 0.31 (95% CI: 0.24 to 0.42) per 1000 person-years compared with 0.04 (95% CI: 0.04 to 0.04) per 1000 person-years for those without an affected sibling, yielding an IRR of 7.58 (95% CI: 5.71 to 10.07). The risk of VSA for siblings with an affected sibling was significantly increased in the fully adjusted model (HR: 2.56; 95% CI: 1.73 to 3.79). No increased risk of VSA was observed in spouses of affected individuals (HR: 0.63; 95% CI: 0.19 to 2.09).

CONCLUSIONS

In this nationwide family study, we identified high familial risk for VSA independent of shared environmental risk factors. Our findings indicate that VSA tends to cluster in families, emphasising the need to explore genetic and non-genetic factors that may contribute.

Severe familial coronary artery spasm in 2 siblings: About 2 cases

Vasospastic angina is the spasm of coronary arteries causing transient myocardial ischemia. VSA is commonly managed with antispasmodic medications including calcium-channel blockers and nitrates. When vasospasm is refractory to conventional medications, unconventional treatment modalities may be used for symptomatic relief. Coronary artery spasm was observed in 2 sisters. Neither of them had significant atheromatous stenosis in the coronary arteries. The 22-year younger sister presented with rest angina in the early morning. The 32-year-old elder sister complained of rest and effort angina. Their coronary angiogram showed spontaneous spasm in the proximal segment of the left anterior descending coronary artery. The youngest one had resistant and recurrent coronary vasospasm involving different segments of the coronary tree causing myocardial infarction with total occlusion of the proximal segment in the left anterior descending coronary artery. Our patients presented with a lesser-known phenomenon called refractory VSA, where intermittent vasospasm continues despite being on a combination of 2 medications. The familial appearance of coronary artery spasm had been previously reported. Although it is not well understood, the underlying mechanism appears to involve a combination of endothelial damage and vasoactive mediators. Genetic factors such as human leucocyte antigen contribute to susceptibility to coronary spasm in some patients with VSA. Treatment for VSA is well documented; however, little data is available for refractory VSA.

Severe hypocalcaemia mimicking acute coronary syndrome

Hypocalcaemia is a common electrolyte deficiency that can be found in up to 28% of hospitalised patients. It may affect cardiac and smooth muscle tone, leading to ECG abnormalities and, in rare cases, coronary spasms and heart failure. This is a case of a pregnant woman in preterm labour who developed vasospastic angina and corrected QT interval (QTc) prolongation on ECG from severe hypocalcaemia, which likely occurred due to iatrogenic hypermagnesaemia. She had a negative diagnostic workup for acute coronary syndrome, and her chest pain and QTc prolongation ultimately resolved with intravenous electrolyte repletion. This case highlights the importance of considering hypocalcaemia on the differential of chest pain that is possibly cardiac in origin.

MINOCA biomarkers: Non-atherosclerotic aspects

Myocardial infarction in the absence of obstructive coronary artery disease (MINOCA) is an important subtype of myocardial infarction. Although comprising less than 50% stenosis in the main epicardial coronary arteries, it constitutes a severe health risk. A variety of approaches have been recommended, but definitive diagnosis remains elusive. In addition, the lack of a comprehensive understanding of underlying pathophysiology makes clinical management difficult and unpredictable. This review highlights ongoing efforts to identify relevant biomarkers in MINOCA to improve diagnosis, individualize treatment and better predict outcomes.

Pharmacotherapy in patients with vasomotor disorders

Background

Anginal symptoms in patients with non-obstructive coronary artery disease are frequently related to vasomotor disorders of the coronary circulation. Although frequently overlooked, a distinct diagnosis of different vasomotor disorders can be made by intracoronary function testing. Early detection and treatment seems beneficial, but little evidence is available for the medical treatment of these disorders. Nevertheless, there are several pharmacotherapeutic options available to treat these patients and improve quality of life.

Methods & findings

We performed an extensive yet non-systematic literature search to explore available pharmacotherapeutic strategies for addressing vasomotor disorders in individuals experiencing angina and non-obstructive coronary artery disease. This article presents a comprehensive overview of therapeutic possibilities for patients exhibiting abnormal vasoconstriction (such as spasm) and abnormal vasodilation (like coronary microvascular dysfunction).

Conclusion

Treatment of vasomotor disorders can be very challenging, but a general treatment algorithm based on the existing evidence and the best available current practice is feasible.

Comprehensive Management of ANOCA, Part 1-Definition, Patient Population, and Diagnosis: JACC State-of-the-Art Review

Angina with nonobstructive coronary arteries (ANOCA) is increasingly recognized and may affect nearly one-half of patients undergoing invasive coronary angiography for suspected ischemic heart disease. This working diagnosis encompasses coronary microvascular dysfunction, microvascular and epicardial spasm, myocardial bridging, and other occult coronary abnormalities. Patients with ANOCA often face a high burden of symptoms and may experience repeated presentations to multiple medical providers before receiving a diagnosis. Given the challenges of establishing a diagnosis, patients with ANOCA frequently experience invalidation and recidivism, possibly leading to anxiety and depression. Advances in scientific knowledge and diagnostic testing now allow for routine evaluation of ANOCA noninvasively and in the cardiac catheterization laboratory with coronary function testing (CFT). CFT includes diagnostic coronary angiography, assessment of coronary flow reserve and microcirculatory resistance, provocative testing for endothelial dysfunction and coronary vasospasm, and intravascular imaging for identification of myocardial bridging, with hemodynamic assessment as needed.

Vasospastic angina: Past, present, and future

Vasospastic angina (VSA) is characterized by episodes of rest angina that are responsive to short-acting nitrates and are attributable to coronary artery vasospasm. The condition is underdiagnosed as the provocation test is rarely performed. VSA, the most important component of non-obstructive coronary artery disease, can present with angina, be asymptomatic, or can even present with fatal arrhythmias and cardiac arrest. Although most patients with VSA respond well to vasodilating medications, prognosis does not improve as expected in most patients, suggesting the existence elusive prognostic factors and pathogenesis that warrant further exploration. Moreover, patients with either severe or refractory VSA barely respond to conventional treatment and may develop life-threatening arrhythmias or suffer sudden cardiac death during ischemic attacks, which are associated with immune-inflammatory responses and have been shown to achieve remission following glucocorticoid and immunoglobulin treatments. Our recent work revealed that inflammation plays a key role in the initiation and development of coronary spasms, and that inflammatory cytokines have predictive value for diagnosis. In contrast to the existing literature, this review both summarizes the theoretical and clinical aspects of VSA, and also discusses the relationship between inflammation, especially myocarditis and VSA, in order to provide novel insights into the etiology, diagnosis, and treatment of VSA.

Coronary Artery Vasospasm in Patients With Eosinophilia

Coronary vasospasm is a relatively well-documented cause for ischemia and myocardial infarction in patients with nonobstructive coronary artery disease. Patients with coexisting eosinophilia present with severe manifestations and are often refractory to traditional therapies. There are few reported cases in the literature. We describe 3 cases occurring within 10 months. (Level of Difficulty: Intermediate.).

Practical Approach for Angina and Non-Obstructive Coronary Arteries: A State-of-the-Art Review

Anginal symptoms are frequently encountered in patients without the presence of significant obstructive coronary artery disease (CAD). It is increasingly recognized that vasomotor disorders, such as an abnormal vasodilatory capacity of the coronary microcirculation or coronary vasospasm, are the dominant pathophysiological substrate in these patients. Although the evidence with respect to angina in patients with non-obstructive coronary arteries is accumulating, the diagnosis and treatment of these patients remains challenging. In this review, we aimed to provide a comprehensive overview regarding the pathophysiological origins of angina with non-obstructive coronary arteries disorders and its diagnostic and therapeutic considerations. Hereby, we provide a practical approach for the management of patents with angina and non-obstructive CAD.

Beta-Blockers and Their Current Role in Maternal and Neonatal Health: A Narrative Review of the Literature

Beta-blockers are a class of medications that act on beta-adrenergic receptors and are categorized as cardio-selective and non-selective. They are principally used to treat cardiovascular conditions such as hypertension and arrhythmias. Beta-blockers have also been used to treat non-cardiogenic indications in non-pregnant individuals and the pediatric population. In pregnancy, labetalol is the mainstay treatment for hypertension and other cardiovascular indications. However, contraindications to certain sub-types of beta-blockers include bradycardia, heart failure, obstructive lung diseases, and hemodynamic instability. There is conflicting evidence of the adverse effects on fetal and neonatal health due to a scarce safety and efficacy profile, and further studies are necessary to understand the pharmacokinetics of the different classes of beta-blockers in pregnancy and fetal health. Understanding the hemodynamic changes during the stages of pregnancy is important to target a more beneficial therapy for both mother and fetus as well as better neonatal outcomes. Beta-blocker use in the pediatric population is less documented in studies but does have the potential to treat various cardiogenic and non-cardiogenic conditions. Future comprehensive studies would further benefit the direction of beta-blocker treatment during pregnancy in neonates and pediatrics.

Allergic Acute Coronary Syndrome-Kounis Syndrome

Acute coronary syndrome (ACS) in the setting of an allergic/immunologic reaction is known as Kounis syndrome. It is an underdiagnosed and underrecognized disease entity. One must keep a high index of suspicions when managing a patient presenting with cardiac as well as allergic symptoms. There are 3 main variants to the syndrome. Treating the allergic reaction may alleviate the pain; however, ACS guidelines should be followed if cardiac ischemia is present.

Anesthetic Management of a Patient With Prinzmetal Angina

Prinzmetal angina (PA) is characterized by the development of reversible vasoconstriction of the coronary arteries, transient ischemic electrocardiographic changes in the ST segment, chest pain at rest, and prompt response to nitrates. Spasms of the coronary arteries can be precipitated during the perioperative period by an imbalance of vasodilator and vasoconstrictor factors of smooth muscle cells, which can lead to myocardial ischemia, cardiac arrhythmias, and death. Nevertheless, this is a relatively unrecognized topic, and literature is scarce about it. We present a case report detailing the successful anesthetic management of a patient diagnosed with PA and a documented nitrate allergy, who underwent bilateral ureterorenoscopy.

Invasive Evaluation for Coronary Vasospasm

Vasospastic angina (VSA) occurs at rest and on exertion, with transient electrocardiographic ischemic changes. VSA presents with spontaneous coronary artery spasm (CAS); it has been associated with stable angina, acute coronary syndromes, and sudden cardiac death. CAS can be identified in normal arteries or non-obstructive coronary atherosclerosis, but is also prevalent in patients with coronary artery disease. The diagnosis is made with invasive coronary reactivity testing with provocation using acetylcholine (Ach). Epicardial spasms can be visualized through coronary angiography as a reversible epicardial vessel narrowing, while the diagnosis of microvascular spasm can be made when angina symptoms and ECG changes happen following intracoronary Ach without epicardial spasm. Identification of CAS allows for risk stratification and specific therapies targeting endothelial dysfunction and paradoxical vascular smooth muscle cell constriction. Therapies include calcium channel blockers as monotherapy or in a combination of a dihydropyridine and non-dihydropyridine. Short-acting nitrates offer acute symptomatic relief but long-acting nitrates should be used sparingly. This current update on invasive evaluation of VSA discusses unified Ach protocols.

Cardiac tamponade-mediated generalized coronary vasospasm presenting as an inferior ST-segment elevation myocardial infarction: a case report

Background

Coronary vasospasm is a rare cause of ST-segment elevation myocardial infarction (STEMI) and can be precipitated by numerous inciting factors including endogenous catecholamines. Differentiating coronary vasospasm from an acute atherothrombotic event is diagnostically challenging and requires a careful clinical history combined with electrocardiographic and angiographic abnormalities to make the diagnosis and guide therapy.

Case Summary

We report a case of cardiogenic shock secondary to cardiac tamponade leading to an endogenous catecholamine surge resulting in profound arterial vasospasm and STEMI. The patient presented with chest pain and inferior ST segment elevations prompting emergent coronary angiography, demonstrating subtotal occlusion of the right coronary artery, severe proximal left anterior descending coronary artery stenosis, and diffusely stenosed aortoiliac vessels. Emergent transthoracic echocardiogram revealed a large pericardial effusion and hemodynamics consistent with cardiac tamponade. Pericardiocentesis resulted in dramatic hemodynamic improvement with immediate normalization of ST segments. Repeat coronary angiography performed one day later showed no angiographically significant coronary or peripheral arterial stenosis.

Discussion

This is the first reported case of simultaneous coronary and peripheral arterial vasospasm presenting as inferior STEMI caused by endogenous catecholamines from cardiac tamponade. Several clues suggest coronary vasospasm including the discordant electrocardiography (ECG) and coronary angiographic findings as well as diffusely stenosed aortoiliac vessels. Diffuse vasospasm was confirmed when repeat angiography performed after pericardiocentesis demonstrated angiographic resolution of coronary and peripheral arterial stenosis. Though rare, circulating endogenous catecholamines resulting in diffuse coronary vasospasm may present as STEMI and should be considered based on the clinical history, ECG findings, and coronary angiography.

Coronary Artery Spasm-Related Heart Failure Syndrome: Literature Review

Although heart failure (HF) is a clinical syndrome that becomes worse over time, certain cases can be reversed with appropriate treatments. While coronary artery spasm (CAS) is still underappreciated and may be misdiagnosed, ischemia due to coronary artery disease and CAS is becoming the single most frequent cause of HF worldwide. CAS could lead to syncope, HF, arrhythmias, and myocardial ischemic syndromes such as asymptomatic ischemia, rest and/or effort angina, myocardial infarction, and sudden death. Albeit the clinical significance of asymptomatic CAS has been undervalued, affected individuals compared with those with classic Heberden's angina pectoris are at higher risk of syncope, life-threatening arrhythmias, and sudden death. As a result, a prompt diagnosis implements appropriate treatment strategies, which have significant life-changing consequences to prevent CAS-related complications, such as HF. Although an accurate diagnosis depends mainly on coronary angiography and provocative testing, clinical characteristics may help decision-making. Because the majority of CAS-related HF (CASHF) patients present with less severe phenotypes than overt HF, it underscores the importance of understanding risk factors correlated with CAS to prevent the future burden of HF. This narrative literature review summarises and discusses separately the epidemiology, clinical features, pathophysiology, and management of patients with CASHF.

Autoimmune limbic encephalitis mimicking inferior myocardial infarction on ECG

A man in his 60s with prior history of coronary artery bypass graft was found collapsed, unresponsive on the floor by family. ECG demonstrated an inferior ST elevation myocardial infarction. However, coronary angiography was negative for a culprit lesion. A faciobrachial dystonic seizure was witnessed during his hospitalisation, ultimately leading to a diagnosis of leucine-rich glioma-inactivated 1 (LGI-1) autoimmune encephalitis. It is likely that neurogenic stunned myocardium led to this presentation.

Case report: Ioversol induced Kounis syndrome and cardiogenic shock

A 50-year-old male patient was admitted to the Cardiology Department of our hospital for intermittent chest pain for 9 days. Coronary angiography showed approximately 70% stenosis in the middle part of the left anterior descending branch. When the procedure was about to end, the patient experienced dyspnea, facial flushing and fall of blood pressure suddenly. At this time, the angiography showed severe spasm and stenosis of the left coronary artery. With antianaphylaxis, pressor therapy, fluid resuscitation and intracoronary administration of nitroglycerin, the left coronary spasm was relieved. A diagnosis of type II kounis syndrome induced by ioversol with cardiogenic shock was made.