Coronary artery spasm: review and update

Lack of Class I Vasoreactivity Testing for Diagnosing Patients With Coronary Artery Spasm

BACKGROUND

Vasoreactivity testing, such as intracoronary acetylcholine (ACh) or ergometrine (EM), is defined as Class I for the diagnosis of patients with vasospastic angina (VSA) according to recommendations from the Coronary Vasomotion Disorders International Study (COVADIS) group and guidelines from the Japanese Circulation Society (JCS).

HYPOTHESIS

Although vasoreactivity testing is a clinically useful tool, it carries some risks and limitations in diagnosing coronary artery spasm.

METHODS

Previous reports on vasoreactivity testing for diagnosing the presence of coronary spasm are summarized from the perspective of Class I.

RESULTS

There are several problems such as reproducibility, underestimation, overestimation, and inconclusive/nonspecific results associated with daily spasm. Because provoked spasm caused by intracoronary ACh is not always similar to that caused by intracoronary EM, possibly due to different mediators, supplementary use of these vasoreactivity tests is necessary for cardiologists to diagnose VSA when a provoked spasm is not revealed by each vasoactive agent.

CONCLUSIONS

Cardiologists should understand the imperfection of these vasoreactivity tests when diagnosing patients with VSA.

Canadian Cardiovascular Society/Canadian Women's Heart Health Alliance Clinical Practice Update on Myocardial Infarction With No Obstructive Coronary Artery Disease (MINOCA)

Myocardial infarction with no obstructive coronary artery disease (MINOCA) represents 6%-15% of all acute coronary syndromes, and women are disproportionately represented. MINOCA is an encompassing preliminary diagnosis, and emerging evidence supports a more expansive comprehensive diagnostic and therapeutic clinical approach. The current clinical practice update summarizes the latest evidence regarding the epidemiology, clinical presentation, and diagnostic evaluation of MINOCA. A cascaded approach to diagnostic workup is outlined for clinicians, for noninvasive and invasive diagnostic pathways, depending on clinical setting and local availability of diagnostic modalities. Evidence concerning the nonpharmacological and pharmacological treatment of MINOCA are presented and summarized according to underlying cause of MINOCA, with practical tips on the basis of expert opinion, outlining a real-life, evidence-based, comprehensive approach to management of this challenging condition.

Recurrent syncope due to ischemia with non-obstructive coronary artery disease: a case report

BACKGROUND

Ischemia with non-obstructive coronary artery disease is a prevalent form of ischemic heart disease. The majority of ischemia with non-obstructive coronary artery disease cases are attributed to underlying factors such as coronary microvascular dysfunction (CMD) and/or coronary artery spasm. Ischemia with non-obstructive coronary artery disease can present with various clinical manifestations. Recurrent syncope is an atypical complaint in patients with ischemia with non-obstructive coronary artery disease.

CASE PRESENTATION

This case report describes the presentation of a 58-year-old Chinese male patient who experienced repeated episodes of syncope. The syncope was found to be caused by concomitant coronary artery spasm and presumptive coronary microvascular dysfunctionc suggested by "slow flow" on coronary angiography. The patient was prescribed diltiazem sustained-release capsules, nicorandil, and atorvastatin. During the three-month follow-up conducted on our outpatient basis, the patient did not experience a recurrence of syncope.

CONCLUSION

This study highlights the importance of considering ischemia with non-obstructive coronary artery disease as a potential cause of syncope in the differential diagnosis. It emphasizes the need for early diagnosis of ischemia with non-obstructive coronary artery disease to facilitate more effective management strategies.

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.

An Unusual Case of Vasospastic Angina Resulting in Multiple Episodes of Cardiac Arrest

Coronary vasospasm is a well-recognized cause of angina (also known as Prinzmetal angina) and a common cause of admissions to the emergency department and coronary intensive care units. It is however an uncommon cause of cardiac arrest. We describe a patient with multiple episodes of chest pain followed by cardiac arrest in pulseless electrical activity (PEA) due to coronary vasospasm. Telemetry and electrocardiography showed ST-segment elevation followed by PEA. Each event was short-lived and resolved after a maximum of six minutes of advanced life support measures. The patient was started on treatment with a dihydropyridine calcium channel blocker (CCB) and nitroglycerin patch with no further episodes recorded to date.

Intraoperative Coronary Spasm: A Potential Case of Vasospastic Angina

Prinzmetal's angina typically features spasms of the coronary arteries due to the hyperreactivity of the vascular smooth muscle cells of the vessels to a nonspecific stimulus. Reports of coronary spasm during general anesthesia are rare, but in such cases, diagnosis is suggested by a framework of angina at rest and changes in the electrocardiogram (ECG) or coronary reactivity tests with ergonovine or acetylcholine. The present study describes a case of coronary spasm induced by general anesthesia associated with several cardiovascular risk factors and the usage of vasoactive drugs that was documented by angiography without using stimulating drugs and treated with intracoronary nitroglycerin. The patient was a 58-year-old male who was designated for carotid endarterectomy due to the stenosis (70%) of the right internal carotid artery by an atheromatous plaque after visiting the emergency department with a sensorimotor deficit in the left upper limb and bifrontal headaches with sudden onset. During the surgical intervention, after the administration of 10 mg of intravenous ephedrine, cardiorespiratory arrest occurred, with alternation between defibrillable and non-defibrillable heart paces. After the recovery of spontaneous circulation after 50 minutes of resuscitation maneuvers, the patient was transported to the hemodynamics laboratory, where there were recurrent episodes of ventricular fibrillation during the angioplasty of the anterior descending artery. After direct stent implantation, pre- and post-stent spasms were verified and reversed after the administration of intracardiac nitroglycerin. The spasm was a possible complication of anesthesia and responded to treatment with nitrates and calcium channel blockers. We would like to emphasize the importance of cardiac monitoring during surgery and anesthesia.

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.

Sudden cardiac arrest due to recurrent coronary spasm in a young woman: a case report

Background

Coronary artery spasm (CAS) is a pathological condition resulting from transient functional narrowing of the coronary arteries leading to myocardial ischaemia and in some rare cases even to sudden cardiac arrest (SCA). The most important preventable risk factor is use of tobacco, whereas possible precipitating factors include some medications and psychological stress.

Case summary

A 32-year-old woman was hospitalized with burning chest pain. The immediate investigations revealed the diagnosis of non-ST-segment elevation myocardial infarction, because of ST elevations in one single lead and increased high-sensitivity troponin. Due to ongoing chest pain and a severe impaired left ventricular ejection fraction (LVEF) of 30% with apical akinesia, a prompt coronary angiography (CAG) was scheduled. After aspirin administration, she developed anaphylaxis with pulseless electrical activity (PEA). She could be resuscitated successfully. CAG revealed multi-vessel CAS for which she received calcium channel blockers. Five days after, she suffered from a second SCA due to ventricular fibrillation and was resuscitated again. Repeated CAG showed no critical coronary artery occlusion. LVEF improved progressively during hospitalization. Drug therapy was increased, and a subcutaneous implantable cardioverter defibrillator (ICD) was implanted for secondary prevention.

Discussion

CAS may in some instances lead to SCA, especially in case of multi-vessel involvement. Allergic and anaphylactic events can trigger CAS, which are frequently underestimated. Regardless of the cause, cornerstone of CAS prophylaxes remains optimal medical therapy as in the avoidance of predisposing risk factors. In case of life-threatening arrhythmia, the implantation of an ICD should be considered.

A case report and literature review of myocardial infarction with nonobstructive coronary arteries (MINOCA) possibly due to acute coronary vasospasm induced by misoprostol

Coronary artery vasospasm (CVS), an uncommon cause of acute chest pain, can be provoked by vasoconstriction-induced medications. Misoprostol, a prostaglandin analog, is a safe medication to terminate a pregnancy. However, misoprostol can cause coronary artery vasospasm due to vasoconstrictor properties, leading to acute myocardial infarction with nonobstructive coronary arteries (MINOCA), especially in patients with a high risk for cardiovascular disease. We report a case of a 42-year-old female with a past medical history of hypertension who presented with ST-elevation myocardial infarction following the administration of a high-dose Misoprostol. The fact that coronary angiogram and intravascular ultrasound revealed normal coronary arteries suggested transient coronary vasospasm. CVS is a severe but rare cardiac adverse effect associated with high-dose misoprostol. This medication should be prescribed with caution and close monitoring, especially in those with pre-existing heart disease or cardiovascular risk factors. Our case raises awareness of severe cardiovascular complications that can be related to using misoprostol in high-risk patients.

MINOCA Phenotypes - A Challenge for Patient-Specific Management

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a puzzling clinical phenomenon with an unclear prognosis, characterized by evidence of myocardial infarction (MI) with normal or near-normal coronary arteries on angiography1. Currently, there are no guidelines for management, and many patients are discharged without a determined etiology, often meaning that optimal treatment gets postponed.We report three MINOCA case studies with main pathophysiological cardiac causes, particularly epicardial, microvascular, and non-ischemic, prompting differential management. The patients presented with acute chest pain, troponin raise, and no angiographically significant coronary disease.In this study, we analyzed the etiology, clinical diagnosis, and treatment of MINOCA concerning the relevant literature.MINOCA is considered to be a dynamic working diagnosis, including coronary, myocardial, and non-coronary disorders. Prospective studies and registries are needed to improve patient care and outcome.

Antispastic Effect of Fasudil and Cocktail of Fasudil and Nitroglycerin in Internal Thoracic Artery

BACKGROUND

Spasm of arterial grafts in coronary artery bypass grafting is a clinical problem and can occasionally be lethal. Perioperative spasm in the internal thoracic artery (ITA) and coronary arteries occurs in 0.43% of patients. This study aimed to investigate the antispastic effect of a RhoA/Rho-kinase (Rho-associated coiled-coil-containing protein kinase [ROCK]) inhibitor (fasudil) with and without nitroglycerin in combination in the ITA.

METHODS

Isolated human ITA rings taken from 68 patients who were undergoing coronary bypass were studied in a myograph. Cumulative concentration-relaxation curves for fasudil (-9 to -3.5 log M) were established in the ITA, which was precontracted with potassium chloride or U46619. The inhibitory effect of fasudil (-6.3 or -5.3 log M) or fasudil in combination with nitroglycerin were also tested. The ROCK2 protein was measured by Western blot.

RESULTS

Fasudil caused similar relaxation in ITA rings contracted by potassium chloride or U46619. Pretreatment with -5.3 log M fasudil significantly depressed contraction induced by potassium chloride (P = .004 vs control; P = .017 vs -6.3 log M) and U46619 (P = .010 vs control; P = .041 vs. -6.3 log M). Fasudil in combination with nitroglycerin had more effect and more rapid and sustained relaxation than either vasodilator alone. Fasudil caused a decrease of ROCK2 protein content (P = .014).

CONCLUSIONS

Fasudil fully relaxes some vasoconstrictor-induced contraction and decreases ROCK2 protein content in the ITA. The combination of fasudil and nitroglycerin has a superior effect than either vasodilator alone. The new cocktail solution composed of fasudil and nitroglycerin (pH 7.4) has effective antispastic action and may prove to be a new antispastic method for arterial conduits during coronary bypass surgery.

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.

New Insights into Pathophysiology and New Risk Factors for ACS

Cardiovascular disease still represents the main cause of mortality worldwide. Despite huge improvements, atherosclerosis persists as the principal pathological condition, both in stable and acute presentation. Specifically, acute coronary syndromes have received substantial research and clinical attention in recent years, contributing to improve overall patients' outcome. The identification of different evolution patterns of the atherosclerotic plaque and coronary artery disease has suggested the potential need of different treatment approaches, according to the mechanisms and molecular elements involved. In addition to traditional risk factors, the finer portrayal of other metabolic and lipid-related mediators has led to higher and deep knowledge of atherosclerosis, providing potential new targets for clinical management of the patients. Finally, the impressive advances in genetics and non-coding RNAs have opened a wide field of research both on pathophysiology and the therapeutic side that are extensively under investigation.

α1A Adrenoreceptor blockade attenuates myocardial infarction by modulating the integrin-linked kinase/TGF-β/Smad signaling pathways

Background

Myocardial infarction (MI) is considered a public health problem. According to the World Health Organization, MI is a leading cause of death and comorbidities worldwide. Activation of the α1A adrenergic receptor is a contributing factor to the development of MI. Tamsulosin, an α1A adrenergic blocker, has gained wide popularity as a medication for the treatment of benign prostatic hyperplasia. Limited evidence from previous studies has revealed the potential cardioprotective effects of tamsulosin, as its inhibitory effect on the α1A adrenoceptor protects the heart by acting on the smooth muscle of blood vessels, which results in hypotension; however, its effect on the infarcted heart is still unclear. The mechanisms of the expected cardioprotective effects mediated by tamsulosin are not yet understood. Transforming growth factor-beta (TGF-β), a mediator of fibrosis, is considered an attractive therapeutic target for remodeling after MI. The role of α1A adrenoceptor inhibition or its relationships with integrin-linked kinase (ILK) and TGF-β/small mothers against decapentaplegic (Smad) signaling pathways in attenuating MI are unclear. The present study was designed to investigate whether tamsulosin attenuates MI by modulating an ILK-related TGF-β/Smad pathway.

Methods

Twenty-four adult male Wistar rats were randomly divided into 4 groups: control, ISO, TAM, and ISO + TAM. ISO (150 mg/kg, intraperitoneally) was injected on Days 20 and 21 to induce MI. Tamsulosin (0.8 mg/kg, orally) was administered for 21 days, prior to ISO injection for 2 consecutive days. Heart-to-body weight ratios and cardiac and fibrotic biomarker levels were subsequently determined. ILK, TGF-β1, p-Smad2/3, and collagen III protein expression levels were determined using biomolecular methods.

Results

Tamsulosin significantly attenuated the relative heart-to-body weight index (p < 0.5) and creatine kinase-MB level (p < 0.01) compared with those in the ISO control group. While ISO resulted in superoxide anion production and enhanced oxidative damage, tamsulosin significantly prevented this damage through antioxidant defense mechanisms, increasing glutathione and superoxide dismutase levels (p < 0.05) and decreasing lipid peroxide oxidation levels (p < 0.01). The present data revealed that tamsulosin reduced TGF-β/p-Smad2/3 expression and enhanced ILK expression.

Conclusion

Tamsulosin may exert a cardioprotective effect by modulating the ILK-related TGF-β/Smad signaling pathway. Thus, tamsulosin may be a useful therapeutic approach for preventing MI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-023-03188-w.

Hypoglycemic Hemiplegia Associated with Reversible Narrowing of the Contralateral Middle Cerebral Artery in a Patient with Adrenal Insufficiency

A 56-year-old man with a 2.5-month history of anorexia developed sweating, weakness, and left hemiplegia and hemispatial neglect. Brain magnetic resonance imaging detected no abnormalities, but magnetic resonance angiography revealed narrowing of the right middle cerebral artery (MCA). The focal neurological signs and narrowing of the MCA resolved after detection and correction of hypoglycemia. Endocrinological examinations indicated adrenal insufficiency. Hemiplegia is a rare but important neurological manifestation of hypoglycemia, although the mechanisms involved remain unknown. Combined hypoglycemia and decreased MCA blood flow associated with vasospasm probably induced regionally severe neuroglycopenia with ischemia, which presented as focal neurological symptoms.

Relationship between Inflammation and Vasospastic Angina

Coronary artery spasm (CAS) is a dynamic coronary stenosis causing vasospastic angina (VSA). However, VSA is a potentially lethal medical condition with multiple presentations, including sudden cardiac death. Despite investigations to explore its pathogenesis, no single mechanism has been found to explain the entire process of VSA occurrence. The roles of elevated local and systemic inflammation have been increasingly recognized in VSA. Treatment strategies to decrease local and systemic inflammation deserve further investigation.

Case report: A rare manifestation of vasospasm induced myocardial infarction with ST-segment elevation in a young male patient

Background

Minority of acute myocardial infarctions (MI) are caused by a non-atherosclerotic occlusion of the coronary artery. We present a case report, where MI with ST-segment elevation was provoked by a vasospasm, which is a rare aetiological finding.

Case presentation

27-year-old male patient presented to the emergency department because of a sudden onset chest pain radiating to the left arm. The patient underwent percutaneous coronary intervention (PCI) to the right coronary artery (RCA) 3 months ago due to inferior wall MI, however, chest pain episodes kept on recurring at night throughout the whole period after the intervention. During current admission, initial electrocardiogram (ECG) demonstrated ST-segment elevation in leads II, III and aVF. Coronary angiogram revealed diffuse severe narrowing of the right coronary artery, which was relieved with intracoronary administration of nitrates and verapamil. After coronary angiogram patient was given oral long-acting nitrates and verapamil, however, during the following days nocturnal chest pain episodes reoccurred. It was decided to swap verapamil to diltiazem, which led to complete cessation of angina episodes. The patient was discharged in stable condition and symptom free. It was suspected that the first MI was of vasospastic origin, which likely led to unnecessary stenting.

Conclusions

This clinical case has demonstrated the challenges clinician could face in order to correctly diagnose vasospasm-induced MI because of its rare occurrence and highly variable presentation. We strongly suggest using intracoronary nitroglycerine during coronary angiography as a standard practice to avoid a potential diagnostic error and unnecessary stenting. Although, in some cases the reason behind coronary artery spasm (CAS) remains unclear, medical treatment can be very effective for CAS prevention.

Epicardial atherosclerosis and coronary tortuosity in patients with acetylcholine-induced coronary spasm

BACKGROUND

Angina pectoris in the absence of relevant epicardial stenoses is frequently caused by coronary spasm. This mechanism of angina is common yet underdiagnosed in daily clinical practice. The pathophysiology of coronary spasm is complex, multifactorial, and not completely understood. The purpose of this study was to analyze the relationship between macroscopic coronary morphologies and coronary spasm.

METHODS

Epicardial atherosclerosis, coronary vessel tortuosity, coronary aneurysms, and myocardial bridges were analyzed angiographically in 610 patients and a potential association with the result of an intracoronary acetylcholine (ACh) provocation test was investigated.

RESULTS

The comparison showed that angiographic morphologic variations in the coronary arteries are related to the occurrence of coronary spasm. We observed a strong association between the presence of epicardial atherosclerosis and epicardial spasm [87 patients of 179 with epicardial spasm had epicardial atherosclerosis (49%) vs. 45 patients of 172 with microvascular spasm (26%) vs. 89 patients of 259 with negative/inconclusive ACh test (36%); P < 0.005]. Moreover, we found a higher frequency of coronary tortuosity in patients with microvascular spasm [99 patients of 172 with microvascular spasm had at least moderate coronary tortuosity (58%) vs. 76 patients of 179 with epicardial spasm (43%) vs. 126 patients of 259 with negative/inconclusive ACh test (49%); P = 0.017]. Multivariable analysis revealed epicardial atherosclerosis (<50% stenosis) on coronary angiography as a predictor for epicardial spasm (OR, 2.096; 95% CI, 1.467-2.995; P < 0.0005). Female sex (OR, 5.469; 95% CI, 3.433-8.713; P < 0.0005), and exertional angina (OR, 2.411; 95% CI, 1.597-3.639; P < 0.0005) were predictors of microvascular spasm in multivariable analysis.

CONCLUSION

In angina patients with no obstructive coronary artery disease, epicardial atherosclerosis is associated with ACh-induced epicardial coronary spasm. Moreover, coronary microvascular spasm is more prevalent in female patients and those with exertional angina. Our results provide insights into the relationship between coronary morphology and coronary vasomotor function.

Successful Use of Continuous Erector Spinae Plane Blocks in a Patient With Variant Angina After Large Ventral Hernia Repair

Coronary artery spasm constitutes the primary underlying pathology of variant angina. Because provocation of coronary artery spasm may occur with both excess sympathetic and excess parasympathetic stimulation, patients with this disorder have extremely limited options for perioperative pain control. This is especially true for procedures involving extensive abdominal incision/manipulation. Whereas neuraxial analgesia might otherwise be appropriate in these cases, several studies have demonstrated that coronary artery spasm can occur as a result of epidural placement, and therefore, that this may not be an optimal choice for patients with variant angina. This report discusses the case of a patient with a preexisting diagnosis of variant angina who underwent an exploratory laparotomy with large ventral hernia repair and for whom continuous erector spinae plane blocks were successfully used as analgesic adjuncts without triggering coronary artery spasm.

Serum SELENBP1 and VCL Are Effective Biomarkers for Clinical and Forensic Diagnosis of Coronary Artery Spasm

Coronary artery spasm (CAS) plays an important role in the pathogenesis of many ischemic heart entities; however, there are no established diagnostic biomarkers for CAS in clinical and forensic settings. This present study aimed to identify such serum biomarkers by establishing a rabbit CAS provocation model and integrating quantitative serum proteomics, parallel reaction monitoring/mass spectrometry-based targeted proteomics, and partial least-squares discriminant analysis (PLS-DA). Our results suggested that SELENBP1 and VCL were potential candidate biomarkers for CAS. In independent clinical samples, SELENBP1 and VCL were validated to be significantly lower in serum but not blood cells from CAS patients, with the reasons for this possibly due to the decreased secretion from cardiomyocytes. The areas under the curve of the receiver operating characteristics (ROC) analysis were 0.9384 for SELENBP1 and 0.9180 for VCL when diagnosing CAS. The CAS risk decreased by 32.3% and 53.6% for every 10 unit increases in the serum SELENBP1 and VCL, respectively. In forensic samples, serum SELENBP1 alone diagnosed CAS-induced deaths at a sensitivity of 100.0% and specificity of 72.73%, and its combination with VCL yielded a diagnostic specificity of 100.0%, which was superior to the traditional biomarkers of cTnI and CK-MB. Therefore, serum SELENBP1 and VCL could be effective biomarkers for both the clinical and forensic diagnosis of CAS.

E-cigarettes and their lone constituents induce cardiac arrhythmia and conduction defects in mice

E-cigarette use has surged, but the long-term health effects remain unknown. E-cigarette aerosols containing nicotine and acrolein, a combustion and e-cigarette byproduct, may impair cardiac electrophysiology through autonomic imbalance. Here we show in mouse electrocardiograms that acute inhalation of e-cigarette aerosols disturbs cardiac conduction, in part through parasympathetic modulation. We demonstrate that, similar to acrolein or combustible cigarette smoke, aerosols from e-cigarette solvents (vegetable glycerin and propylene glycol) induce bradycardia, bradyarrhythmias, and elevations in heart rate variability during inhalation exposure, with inverse post-exposure effects. These effects are slighter with tobacco- or menthol-flavored aerosols containing nicotine, and in female mice. Yet, menthol-flavored and PG aerosols also increase ventricular arrhythmias and augment early ventricular repolarization (J amplitude), while menthol uniquely alters atrial and atrioventricular conduction. Exposure to e-cigarette aerosols from vegetable glycerin and its byproduct, acrolein, diminish heart rate and early repolarization. The pro-arrhythmic effects of solvent aerosols on ventricular repolarization and heart rate variability depend partly on parasympathetic modulation, whereas ventricular arrhythmias positively associate with early repolarization dependent on the presence of nicotine. Our study indicates that chemical constituents of e-cigarettes could contribute to cardiac risk by provoking pro-arrhythmic changes and stimulating autonomic reflexes.

Cellular Mechanisms of Coronary Artery Spasm

Coronary artery spasm (CAS) is a reversible phenomenon caused by spontaneous excessive vascular smooth muscle contractility and vascular wall hypertonicity, which results in partial or complete closure of the lumen of normal or atherosclerotic coronary arteries. The clinical picture of CAS includes chest discomfort which is similar in quality to that of stable effort angina. Mechanisms underlying the development of CAS are still unclear. CAS certainly is a multifactorial disease. In this review, we paid attention to the role of the main pathophysiologic mechanisms in CAS: endothelial dysfunction, chronic inflammation, oxidative stress, smooth muscle hypercontractility, atherosclerosis and thrombosis, and mutations leading to deficient aldehyde dehydrogenase 2 (ALDH2) activity. These findings might shed novel insight on the underlying mechanisms and identify potential diagnostic and therapeutic targets for cardiovascular diseases in the future.

Coronary Vasospastic Angina: A Review of the Pathogenesis, Diagnosis, and Management

Vasospastic angina (VSA) is an under-appreciated cause of chest pain. It is characterised by transient vasoconstriction of the coronary arteries and plays a significant role in the pathogenesis of stable angina and acute coronary syndromes. Complex mechanistic pathways characterised by endothelial dysfunction and smooth muscle hypercontractility lead to a broad spectrum of clinical manifestations ranging from recurrent angina to fatal arrhythmias. Invasive provocation testing using intracoronary acetylcholine or ergonovine is considered the current gold standard for diagnosis, but there is a wide variation in protocols amongst different institutions. Conventional pharmacological therapy relies on calcium channel blockers and nitrates; however, refractory VSA has limited options. This review evaluates the pathophysiology, diagnostic challenges, and management strategies for VSA. We believe global efforts to standardise diagnostic and therapeutic guidelines will improve the outcomes for affected patients.

Life-Threatening Coronary Vasospasm Treated by Implantable Cardioverter Defibrillator: The Warning Signs

Coronary artery vasospasm is the sudden narrowing of an artery caused by rapid prolonged contraction. It reduces blood supply to the heart and can present with typical cardiac chest pain symptoms. Vasospasm can lead to fatal arrhythmic complications such as ventricular fibrillation. Our case report describes an example of this occurring in a 53-year-old female, and the management plan that ensued. We look at the importance of accurate and prompt diagnosis of vasospasm and how this can have implications for treatment options. One of the available treatments for vasospasm is placement of an implantable cardioverter defibrillator (ICD). This delivers a shock in the event of future life-threatening arrhythmia, with the aim of preventing cardiac arrest. ICD placement, however, is not always a suitable option. This case report discusses the various challenges that arose while making the decision for ICD placement and gives insight into the best available treatment options for coronary artery vasospasm. We also highlight early warning signs that predict life-threatening vasospastic events and how this can be diagnosed and treated appropriately.

Intractable right coronary artery spasm in the early postoperative period after heart transplantation: a case report

Coronary artery spasm after heart transplantation is a very rare complication. In one observational study and many anecdotal reports, most cases of coronary artery spasm occurred more than 1 year after surgery and had good outcomes. However, cases of intractable coronary artery spasm during the early postoperative period resulting in fatality are limited. This report presents a case of two cardiac arrests caused by coronary artery spasms within a short period of time after heart transplantation.

Coronary Artery Spasm: Risk Factors, Pathophysiological Mechanisms and Novel Diagnostic Approaches

Coronary artery spasm (CAS) is a transient reversible subtotal or complete occlusion induced by coronary hypercontraction and the critical cause of myocardial ischaemia with non-obstructive coronary arteries. During the past decades, our knowledge of the risk factors and pathophysiological mechanisms of CAS have been increasingly progressed, and various diagnostic approaches, including imaging technologies and novel biomarkers, have been proposed to serve well to diagnose CAS clinically. This review aims to summarize these research progresses on the risk factors of CAS and introduce current knowledge about the mechanisms accounting for CAS, including endothelial dysfunction, vascular smooth muscle cell hyperreactivity, and adventitial and perivascular adipose tissue inflammation. We also gathered the recently evolved diagnostic approaches and analyzed their advantages/disadvantages, in purpose of enhancing the diagnostic yield on the basis of ensuring accuracy.

Perioperative coronary artery spasm after off-pump coronary artery bypass grafting in the non-manipulated coronary artery

BACKGROUND

Perioperative coronary artery spasm (CAS) following coronary artery bypass grafting (CABG) is a severe or lethal condition that is rarely reported. In addition, rare cases with CAS following CABG in the non-manipulated coronary artery are angiographically documented in the perioperative period. We aimed to report our experiences on the diagnosis and treatment of a case with CAS following off-pump CABG in the non-manipulated coronary artery.

METHODS

A 57-year old male with coronary heart disease and unstable angina willing to undergo CABG was admitted to our department. CABG was recommended as he showed 90% stenosis in distal left anterior descending artery, 90% stenosis in intermediate branch, 90% stenosis in left circumflex coronary artery, as well as 50% stenosis in proximal right coronary artery (RCA).

RESULTS

After CABG, the patient showed Adams-Stokes syndrome and ST-segment elevation. Then CPR was conducted and coronary angiography indicated perioperative CAS in the non-manipulated posterior descending artery. For the treatment, the patient received nitroglycerin injection into the coronary artery by catheter and pumping of diltiazem. Finally, the patient was discharged on day 7 after surgery. A comprehensive literature search was conducted to summarize the studies focused on the diagnosis and treatment of such condition, which indicated that all of the CAS cases occurred in the manipulated vessels, except one study showing CAS in the untouched native coronary artery which was similar with our case.

CONCLUSIONS

Perioperative CAS in the non-manipulated coronary artery following CABG is a severe or lethal condition that is rarely reported, which deserves close attention by the clinicians in clinical practice.

Apolipoprotein (a)/Lipoprotein(a)-Induced Oxidative-Inflammatory α7-nAChR/p38 MAPK/IL-6/RhoA-GTP Signaling Axis and M1 Macrophage Polarization Modulate Inflammation-Associated Development of Coronary Artery Spasm

Objective. Apolipoprotein (a)/lipoprotein(a) (Lp(a)), a major carrier of oxidized phospholipids, and α7-nicotinic acetylcholine receptor (α7-nAChR) may play an important role in the development of coronary artery spasm (CAS). In CAS, the association between Lp(a) and the α7-nAChR-modulated inflammatory macrophage polarization and activation and smooth muscle cell dysfunction remains unknown. Methods. We investigated the relevance of Lp(a)/α7-nAChR signaling in patient monocyte-derived macrophages and human coronary artery smooth muscle cells (HCASMCs) using expression profile correlation analyses, fluorescence-assisted cell sorting flow cytometry, immunoblotting, quantitative real-time polymerase chain reaction, and clinicopathological analyses. Results. There are increased serum Lp(a) levels (3.98-fold, $p=0.011$ ) and macrophage population (3.30-fold, $p=0.013$ ) in patients with CAS compared with patients without CAS. Serum Lp(a) level was positively correlated with high-sensitivity C-reactive protein ( $r^2=0.48$ , $p<0.01$ ), IL-6 ( $r^2=0.38$ , $p=0.03$ ), and α7-nAChR ( $r^2=0.45$ , $p<0.01$ ) in patients with CAS, but not in patients without CAS. Compared with untreated or low-density lipoprotein- (LDL-) treated macrophages, Lp(a)-treated macrophages exhibited markedly enhanced α7-nAChR mRNA expression ( $p<0.01$ ) and activity ( $p<0.01$ ), in vitro and ex vivo. Lp(a) but not LDL preferentially induced CD80+ macrophage (M1) polarization and reduced the inducible nitric oxide synthase expression and the subsequent NO production. While shRNA-mediated loss of α7-nAChR function reduced the Lp(a)-induced CD80+ macrophage pool, both shRNA and anti-IL-6 receptor tocilizumab suppressed Lp(a)-upregulated α7-nAChR, p-p38 MAPK, IL-6, and RhoA-GTP protein expression levels in cultures of patient monocyte-derived macrophages and HCASMCs. Conclusions. Elevated Lp(a) levels upregulate α7-nAChR/IL-6/p38 MAPK signaling in macrophages of CAS patients and HCASMC, suggesting that Lp(a)-triggered inflammation mediates CAS through α7-nAChR/p38 MAPK/IL-6/RhoA-GTP signaling induction, macrophage M1 polarization, and HCASMC activation.

Inferior Myocardial Infarction Secondary to Coronary Artery Vasospasm Following Regadenoson Stress Imaging

Coronary artery vasospasm is a rare condition that is caused by hyperactive arterial smooth muscle vasoconstriction leading to reversible coronary artery occlusion. Patients that suffer from coronary artery vasospasm have the potential to develop life-threatening conditions such as myocardial infarction and fatal arrhythmias. ST-elevations are a rare complication that can occur in people with coronary vasospasm, and to the best of our knowledge there are no documented cases of ST-elevation myocardial infarction occurring in patients undergoing regadenoson stress test. We present a unique case of a patient with known coronary artery disease and catheter-induced coronary artery vasospasm who developed ST-segment elevations and typical angina immediately following the administration of regadenoson during an elective myocardial stress test.

CT Imaging Findings in Non-Atherosclerotic Coronary Artery Disease

급성 관동맥 증후군(acute coronary syndrome)은 대부분 죽상경화 관상동맥 질환(atherosclerotic coronary artery disease)에 의해 발생하지만, 비죽상경화 관상동맥 질환에서도 발생할 수 있다. 고식적 관상동맥 혈관조영술은 동맥 내강의 협착이나 확장 등의 형상에 대한 정보만을 제공하고, 동맥경화반이나 동맥벽에 대한 평가가 어려워 관상동맥 이상의 원인 질환의 진단에 낮은 특이도를 보인다. 반면, 관상동맥 전산화단층촬영 혈관조영술은 혈관경화반의 특징, 혈관벽의 조영증강뿐 아니라 연접한 대동맥이나 폐동맥의 변화 등도 함께 관찰할 수 있어, 비죽상경화 관상상동맥질환의 진단 및 다양한 원인 감별에 도움이 된다. 따라서 이 종설에서는 다양한 비죽상경화 관상동맥 질환들을 소개하고, 이의 병태생리 및 대표적인 관상동맥 전산화단층촬영 혈관조영술의 영상 소견에 대해 설명하고자 한다.

Comparison of the effects of the time of home-based cardiac rehabilitation program on the changes in cardiometabolic risk factors in patients with phase-IV myocardial infarction: A randomized controlled trial

BACKGROUND

It seems that the time of performing cardiac rehabilitation is important in determining the risk of cardiac complications in patients with myocardial infarction (MI). The present study aimed to investigate the effects of a home-based cardiac rehabilitation program (HCRP) conducted in either the morning or evening on cardiometabolic risk factors in phase IV (maintenance) MI patients.

METHODS

In this randomized controlled clinical trial, 80 patients with MI were divided into 2 groups of intervention and control (40 individuals per group). Patients in each group were categorized into morning and evening subgroups (20 individuals per subgroup). The therapeutic regimen in the intervention group included HCRP, routine medications, and exercise and walking programs for 8 weeks. Patients in the control group received routine treatments for 8 weeks. Cardiovascular risk factors comprising of cardiac troponin I (cTnI), mean platelet volume (MPV), C-reactive protein (CRP), and cardiometabolic indicators including cholesterol (Cho), high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglyceride (TG), and the maximum rate of oxygen consumption (VO2 max) were measured for all patients before and after the intervention.

RESULTS

Our results showed significant reductions in Cho, TG, HDL, LDL, VO2 max, CRP, and MPV (P < 0.05) in the group performing HCRP in the evening compared with the morning group.

CONCLUSION

Performing HCRP in the evening, compared with morning, can be significantly more effective in improving the levels of cardiometabolic risk factors in patients with MI. Therefore, it is recommended that rehabilitation programs be implemented in these patients in evening shifts.

Outpatient Management of Patients With Angina With No Obstructive Coronary Arteries: How to Come to a Proper Diagnosis and Therapy

Two-thirds of women and one-third of men who undergo a clinically indicated coronary angiography for stable angina, have no obstructive coronary artery disease (CAD). Coronary vascular dysfunction is a highly prevalent underlying cause of angina in these so called “Angina with No Obstructive Coronary Arteries (ANOCA)” patients, foremost in middle aged women. Coronary vascular dysfunction encompasses various endotypes, namely epicardial and microvascular coronary spasms, impaired vasodilatation, and increased microvascular resistance. ANOCA patients, especially those with underlying coronary vascular dysfunction, have an adverse cardiovascular prognosis, poor physical functioning, and a reduced quality of life. Since standard ischemia detection tests and coronary angiograms are not designed to diagnose coronary vascular dysfunction, this ischemic heart disease is often overlooked and hence undertreated. But adequate diagnosis is vital, so that treatment can be started to reduce symptoms, reduce healthcare costs and improve quality of life and cardiovascular prognosis. The purpose of this review is to give a contemporary overview of ANOCA with focus on coronary vascular dysfunction. We will provide a possible work-up of patients suspected of coronary vascular dysfunction in the outpatient clinical setting, based on the latest scientific insights and international consensus documents. We will discuss the value of ischemia detection testing, and non-invasive and invasive methods to diagnose coronary vascular dysfunction. Furthermore, we will go into pharmacological and non-pharmacological therapeutic options including anti-anginal regimens and lifestyle interventions.

Pericarditis as a trigger for Prinzmetal angina - a case report

Prinzmetal angina is one of the causes of acute coronary syndromes, the exact etiology of which is still unknown. Here we introduce a 27-year-old man with no history of cardiovascular disease, with a history of hospitalization due to acute pericarditis in the previous month, who was discharged with a good response to ibuprofen treatment but had clinical and electrocardiographically recurrence of pericarditis with compressive retrosternal chest pain and electrocardiogram (ECG) changes in favor of acute infero-postero-right ventricular (RV) myocardial infarction (MI). Treatment with vasodilator improved compressive retrosternal chest pain and reversed acute myocardial infarction changes completely and left pleuritic chest pain and pericarditis changes in the ECG. Due to the typical chest pain, he was admitted to the emergency room; ECG revealed generalized ST-segment elevation with acute pericarditis pattern again. Acute infero-posterior and right ventricular acute myocardial infarction pattern was also evident. After treatment with nitroglycerin in the Critical Cardiac Unit (CCU), all ECG ischemic changes returned to baseline, and pericarditis remained in all leads. The patient was discharged with non-steroidal anti-inflammatory drugs (NSAIDs), calcium channel blockers, and a good general condition.

Coronary Artery Vasospasm Requiring Cardiac Autotransplantation Yet Controlled With Tobacco

Coronary artery vasospasm is typically managed through avoidance of triggers and with symptomatic treatments with calcium channel blockers and long-acting nitrates. Here, we report a rare case of medically refractory coronary artery vasospasm associated with genetic predispositions that initially required cardiac autotransplantation followed paradoxically by nicotine for long-term symptomatic control. (Level of Difficulty: Intermediate.)

Sex and gender in cardiovascular medicine: presentation and outcomes of acute coronary syndrome

Although health disparities in women presenting with acute coronary syndrome (ACS) have received growing attention in recent years, clinical outcomes from ACS are still worse for women than for men. Women continue to experience higher patient and system delays and receive less aggressive invasive treatment and pharmacotherapies. Gender- and sex-specific variables that contribute to ACS vulnerability remain largely unknown. Notwithstanding the sex differences in baseline coronary anatomy and function, women and men are treated the same based on guidelines that were established from experimental and clinical trial data over-representing the male population. Importantly, younger women have a particularly unfavourable prognosis and a plethora of unanswered questions remains in this younger population. The present review summarizes contemporary evidence for gender and sex differences in vascular biology, clinical presentation, and outcomes of ACS. We further discuss potential mechanisms and non-traditional risk conditions modulating the course of disease in women and men, such as unrecognized psychosocial factors, sex-specific vascular and neural stress responses, and the potential impact of epigenetic modifications.

Complete atrio-ventricular block with coronary artery spasm due to direct laryngoscopy in a pediatric patient with laryngeal papillomatosis: a case report

Background

Coronary artery spasm has rarely been reported in pediatric patients. Previous studies have reported comorbidities and risk factors for coronary artery spasms. We present the case of a complete atrio-ventricular (AV) block that occurred in the absence of other risk factors immediately after direct laryngoscopy.

Case presentation

A 2-year-old girl developed severe coronary artery spasm after direct laryngoscopy for elective laryngeal papillomatosis resection. Immediately after the initiation of laryngoscopy, complete AV block and ST elevation on lead II of the electrocardiogram were observed. These findings indicated that the complete AV block was caused by a right coronary artery spasm.

Conclusion

Coronary artery spasm resulting in lethal arrhythmia rarely occurs in healthy pediatric patients. To the best of our knowledge, this is the first pediatric case of a severe coronary artery spasm resulting in a complete AV block due to direct laryngoscopy in a healthy patient.

Idiopathic Effusive-Constrictive Pericarditis Presented by Variant Angina

An 80-year-old man presented to our hospital complaining of loss of appetite. During the medical examination, he developed variant angina accompanied with heart failure. Oral calcium channel blocker therapy controlled his variant angina, but medical management of heart failure became increasingly difficult due to gradually increasing pericardial effusion, and pericardiocentesis leading to the diagnosis of effusive-constrictive pericarditis (ECP). Here, we report a rare case of idiopathic pericarditis caused variant angina with already having endothelial dysfunction and eventually developed ECP.

The use of sentinel skin islands for monitoring buried and semi-buried micro-vascular flaps. Part I: Summary and brief description of monitoring methods

Micro-vascular flaps have been used for the repair of challenging defects for over 45 years. The risk of failure is reported to be around 5-10% which despite medical and technical advances in recent years remains essentially unchanged. Precise, continuous, sensitive and specific monitoring together with prompt notification of vascular compromise is crucial for the success of the procedure. In this review, we provide a classification and brief description of the reported methods for monitoring the micro-vascular flap and a summary of the benefits over direct visual monitoring. Over 40 different monitoring techniques have been reported but their comparative merits are not always obvious. One looks for early detection of a flap's compromise, improved flap salvage rate and a minimal false-positive or false-negative rate. The cost-effectiveness of any method should also be considered. Direct visualisation of the flap is the method most generally used and still seems to be the simplest, cheapest and most reliable method for flap monitoring. Considering the alternatives, only implantable Doppler ultrasound probes, near infrared spectroscopy and laser Doppler flowmetry have shown any evidence of improved flap salvage rates over direct visual monitoring.

Prinzmetal-Like Acute Limb Ischemia

Vasospasm-induced acute limb ischemia (ALI), also known as vasospastic limb ischemia (VLI), is a rare, underreported vascular event. Unlike thrombotic and embolic occlusive etiologies, which often warrant revascularization, vasospasm is a transient phenomenon that may be successfully managed conservatively without surgical intervention. Thus, prompt recognition and accurate diagnosis of VLI is imperative to avoid unnecessary surgical or endovascular procedures. This diagnosis, however, can pose as a challenge for clinicians, as it can present with clinical signs and symptoms near-identical to the presentation of thrombotic-induced ALI. In this report, we present a patient that experienced 2 vasospasm-induced ischemic events; the patient developed Rutherford IIb acute limb-threatening ischemia following cardiac catheterization for myocardial infarction. Computer tomography angiography findings of her right leg revealed acute occlusion suggesting the need for immediate operative intervention for limb salvage. However, due to her critical state, she instead was managed with medical treatments. Despite no intervention, the patient had full resolution of her right leg symptoms. We present this case to highlight the unusual multifocality of vasospastic events and to increase awareness of the diagnostic challenges associated with VLI.

Acute Myocardial Infarction in a 17-year-old High-school Girl

We report an unusual case of acute myocardial infarction in a high school girl. The patient was 17 years of age and had multiple coronary risk factors, including marked obesity with a body mass index (BMI) of 42.7 kg/m², dyslipidemia and glucose intolerance. She had been an on and off smoker since she was 13 years of age. Due to the recent Westernization of the lifestyle, the prevalence of metabolic syndrome in the young generation has been increasing in Japan. Cardiovascular disease based on lifestyle-related diseases may become more common in young people.

Girl Who Cried Wolf: A Case of Prinzmetal Angina With Related ST-Elevation Myocardial Infarction

Prinzmetal variant angina is characterized by episodic chest pain associated with transient ST changes seen on an electrocardiogram (EKG). A 51-year-old female with a pertinent history of non-obstructive coronary artery disease (CAD), non-ST elevation myocardial infarction (NSTEMI) twice, ST-elevation myocardial infarction (STEMI), Prinzmetal angina, ventricular tachycardia s/p implantable cardioverter-defibrillator placement, and gastroesophageal reflux disease presented with 2.5 hours of left-sided chest pain with radiation to the left arm. Her initial EKG was not revealing. However, a subsequent EKG showed ST elevations in the inferior leads. A coronary angiogram was performed and revealed distal right coronary artery spasm that was relieved with intracoronary nitroglycerin. The nature of her chest pain in conjunction with her EKG and angiogram findings helped diagnose her with Prinzmetal angina that was significant enough to result in a STEMI. Thus, Prinzmetal angina and STEMI can be interconnected rather than being separate, mutually exclusive pathologies.

Coincidence between spontaneous and inducible coronary spasm: acetylcholine test is clinically valued for diagnosing coronary spasm

There is no report regarding the correlation between spontaneous documented coronary spasm and acetylcholine (ACh)-inducible spasm. We retrospectively analyzed the coincidence between angiographical spontaneous coronary spasm and ACh-inducible spasm in the same patients. We recruited 28 patients with 30 angiographical spontaneous coronary spasm in 6009 patients with diagnostic and follow-up coronary arteriography from Jan 1991 and Mar 2019 in the cardiac catheterization laboratory. We could perform intracoronary ACh testing in 19 patients with 20 vessels. ACh was injected in incremental dose of 20/50/100 μg into the left coronary artery and 20/50/80 μg into the right coronary artery. Positive spasm was defined as > 90% stenosis and ischemic ECG changes. Angiographical documented spontaneous coronary spasm was observed in 0.47% (28/6009) of patients with diagnostic and follow-up coronary angiography. Intracoronary administration of ACh reproduced 15 spontaneous coronary spasm and no provoked spasm was observed in the remaining 5 vessels due to the administration of nitroglycerine or under medications. Spasm-provoked sites by ACh tests and ACh-inducible spasm configurations were almost similar to spontaneous spasm. Coincidence of provoked spasm site (93.3% vs. 6.7%, p < 0.001) and spasm configuration (93.3% vs. 6.7%, p < 0.001) was markedly higher than discordance. Intracoronary ACh testing can reproduce spontaneous coronary artery spasm in 75% of vessels with almost similar sites and same morphological characteristics irrespective of the administration of nitroglycerine or vasodilators. ACh test is a reliable method to document coronary artery spasm in the clinic.

Association between Coronary Artery Spasm and the risk of incident Diabetes: A Nationwide population-based Cohort Study

Background: Non-diabetic coronary artery spasm (CAS) without obstructive coronary artery disease increases insulin resistance. We investigated the risk of incident type 2 diabetes (diabetes) associated with CAS. Methods: Patient records were retrospectively collected from the Taiwan National Health Insurance Research Database during the period 2000-2012. The matched cohorts consisted of 12,413 patients with CAS and 94,721 patients in the control group. Results: During the entire follow-up, the incidence of newly-diagnosed diabetes was 22.2 events per 1000 person-years in the CAS group and 13.9 events per 1000 person-years in the control group. The increased risk of CAS-related incident diabetes was observed regardless of sex and length of follow-up. The median time to incident diabetes was 2.9 and 3.5 years in the CAS and the control group (P <0.001), respectively, regardless of sex. Although age did not affect the risk of CAS-related incident diabetes, the risk was less apparent in the subgroups of male, dyslipidemia, chronic obstructive pulmonary disease, stroke, gout and medicated hypertension. However, CAS patients aged <50 years compared with patients ≥50 years had a greater risk of incident diabetes in females but not in males. Older CAS patients developed diabetes in a shorter length of time than younger patients. Conclusion: CAS is a risk factor for incident diabetes regardless of sex. However, females aged <50 years have a more apparent risk for CAS-related diabetes than old females, which is not observed in males. The median time of 2.9 years to incident diabetes warrants close follow-up.

Aborted Sudden Cardiac Death from Vasospastic-Induced Ventricular Fibrillation with Normal Coronary Angiography: A Case Report and Review of the Literature

Coronary artery vasospasms have been known to cause episodic angina pectoris, along with ST-T wave changes. In addition, vasospasm if prolonged can cause myocardial ischemia leading to malignant arrhythmias such as ventricular fibrillation and ventricular tachycardia resulting in sudden cardiac death (SCD). Treatment for this disorder can be challenging. Current data is lacking on the management of patients receiving appropriate vasodilator medications who present with Ventricular Fibrillation (VFib) as a consequence of coronary artery vasospasms. We present a case of a 71-year-old man who was hospitalized due to recurrent episodes of coronary vasospasms leading to acute decompensation and VFib with subsequent resuscitation while undergoing cardiac catheterization. We also provide review of the literature and updates on the current guidelines from the American Heart Association on this potentially life-threatening disorder.

PDE1 or PDE5 inhibition augments NO-dependent hypoxic constriction of porcine coronary artery via elevating inosine 3',5'-cyclic monophosphate level

Hypoxic coronary vasospasm may lead to myocardial ischaemia and cardiac dysfunction. Inosine 3',5'-cyclic monophosphate (cIMP) is a putative second messenger to mediate this pathological process. Nevertheless, it remains unclear as to whether levels of cIMP can be regulated in living tissue such as coronary artery and if so, what is the consequence of this regulation on hypoxia-induced vasoconstriction. In the present study, we found that cIMP was a key determinant of hypoxia-induced constriction but not that of the subsequent relaxation response in porcine coronary arteries. Subsequently, coronary arteries were treated with various phosphodiesterase (PDE) inhibitors to identify PDE types that are capable of regulating cIMP levels. We found that inhibition of PDE1 and PDE5 substantially elevated cIMP content in endothelium-denuded coronary artery supplemented with exogenous purified cIMP. However, cGMP levels were far lower than their levels in intact coronary arteries and lower than cIMP levels measured in endothelium-denuded coronary arteries supplemented with exogenous cIMP. The increased cIMP levels induced by PDE1 or PDE5 inhibition further led to augmented hypoxic constriction without apparently affecting the relaxation response. In intact coronary artery, PDE1 or PDE5 inhibition up-regulated cIMP levels under hypoxic condition. Concomitantly, cGMP level increased to a comparable level. Nevertheless, the hypoxia-mediated constriction was enhanced in this situation that was largely compromised by an even stronger inhibition of PDEs. Taken together, these data suggest that cIMP levels in coronary arteries are regulated by PDE1 and PDE5, whose inhibition at a certain level leads to increased cIMP content and enhanced hypoxic constriction.

ST segment depression and ventricular fibrillation in a dog after contrast agent administration

An 11-year-old Toy Poodle underwent a computed tomography examination with contrast (iohexol) enhancement under anesthesia. Heart rate and R-wave amplitude on electrocardiogram (ECG) increased 2.5 min after iohexol administration, and end-tidal carbon dioxide decreased to 12 mmHg. A progressive ST segment depression was observed on ECG. Subsequently, the ECG waveform changed to ventricular fibrillation. However, spontaneous circulation returned following cardiopulmonary resuscitation. Myocardial ischemia or anaphylactic shock was suspected in the dog, which explains the ST segment depression observed on ECG. When performing radiological examinations with a contrast agent, the ECG waveform changes, such as an increase in heart rate, R-wave amplitude, or ST segment depression, should be carefully monitored. This might enable early detection of cardiac dysfunction and the ensuing cardiac arrest in dogs.

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.