Guidelines for diagnosis and treatment of patients with vasospastic angina (Coronary Spastic Angina) (JCS 2013). Circ J. 2014;78:2779-2801. [PMID: 25273915 DOI: 10.1253/circj.cj-66-0098]

Does the intracoronary pressure differ according to two types (diffuse or focal) of coronary spasm?

BACKGROUND

Several reports show that two types of coronary vasospasm (diffuse and focal spasm) are associated with the severity or prognosis of coronary spasm in patients with vasospastic angina (VSA). It is unclear whether intracoronary pressure differs between the two spasm types.

AIM

To investigate such relationships using a pressure wire during the spasm provocation test (SPT) in patients with VSA.

METHODS

Eighty-seven patients with VSA (average age: 67 years; 50 men, 37 women) underwent SPT. During the SPT, a pressure wire was advanced into the distal portion of the right coronary artery and left anterior descending coronary artery, and the ratio of the intracoronary pressure to the aortic pressure (Pd/Pa) was continuously monitored. An SPT was performed using acetylcholine (ACh), and the presence of coronary spasm was defined as the presence of > 90% arterial narrowing in response to an ACh infusion, with the usual chest symptoms and/or ischemic ECG changes. Focal spasm was defined as total or subtotal spasm within one segment of the AHA classification, while diffuse spasm was defined as > 90% spasm with two or more segments.

RESULTS

Among 87 patients, the frequencies of metabolic syndrome and having coronary atherosclerosis were higher in the focal group (n = 33) than in the diffuse spasm group (n = 54, P < 0.05). In the vessel analyses, in these 134 spastic segments, diffuse and focal spasms were detected in 100 and 34 vessels, respectively. The Pd/Pa at baseline was similar in both groups (diffuse: 0.96 ± 0.05, focal: 0.95 ± 0.05, P = 0.35); however, the Pd/Pa during coronary spasm was lower in focal spastic vessels (0.66 ± 0.20) than in diffuse spastic vessels (0.76 ± 0.11, P < 0.01), and the reduction in Pd/Pa during an SPT was also lower in focal spastic vessels (-0.29 ± 0.20) than in diffuse spastic vessels (-0.18 ± 0.11, P < 0.01). The presence of focal spasm was a significant factor responsible for reduction in Pd/Pa during SPT.

CONCLUSION

These findings suggest that focal spasm may be more severe than diffuse spasm, judging from the intracoronary pressure during coronary spasm.

Simultaneous total occlusion due to spasm of 2 main coronary arteries: A case report

RATIONALE

Coronary artery spasm (CAS) defined by severe reversible focal or diffuse vasoconstriction, plays an essential role in the pathophysiology of acute coronary syndrome but is not very common in the clinic. Due to its transience, it is difficult to diagnose CAS directly, many patients are diagnosed by clinical experience. Here, we report the diagnosis and treatment of a rare case of simultaneous total occlusion due to spasm of the two main coronary arteries by coronary angiography (CAG).

PATIENT CONCERNS

A 47-year-old man with no medical history was admitted to our emergency room complaining of sudden-onset chest pain lasting 3 hours. Emergency CAG showed total occlusion of the proximal left anterior descending artery and right coronary artery.

DIAGNOSES

Acute myocardial infarction caused by CAS was diagnosed, according to CAG findings and test results.

INTERVENTIONS

Intracoronary injection of nitroglycerin and anti-spasm medication.

OUTCOMES

The patient was discharged on the 8th day with complete resolution of symptoms and normalization of the electrocardiography findings. No ischemic events occurred during a follow-up for 27 months.

LESSONS

This case highlights the significance of identifying CAS in patients with acute myocardial infarction and avoiding blind interventional stent therapy, which requires closer attention from clinicians.

Comparison of various calcium antagonist on vasospastic angina: a systematic review

BACKGROUND

Coronary artery vasospasm is an abnormal spasm of coronary arteries that cause transient or complete occlusion without exertion. It causes stable angina to ACS. However, this can be prevented by calcium channel blockers (CCBs) which suppress Ca²⁺ influx into the vascular muscle cells. Nevertheless, several CCBs adverse effects are harmful for these patients. Selecting the right CCBs would give the best clinical practice.

METHOD

The studies were obtained from four major medical databases by various keywords. Inclusion and exclusion criteria were implemented as adult >18 years, observational study, English language and drug of interest. Duplicates were eliminated, and the remaining studies were reviewed. Final full-texts assessment was conducted independently by Newcastle-Ottawa Scale and Revised Cochrane.

RESULTS

The search found 1378 articles. However, six studies were selected after implementing the study criteria. Diltiazem was found to decrease angina and increase quality of life until 12th week of treatment; however, some adverse effects include atrioventricular block and recurrent angina up till 4th week were found. Meanwhile, nifedipine was found to decrease vasospastic angina (VSA) by the fourth and eighth weeks of treatment. Nevertheless, it caused excessive drop in BP and increase heart rate by eighth week. In addition, slow-release preparation of both CCBs were found to increase efficacy and compliance. Lastly amlodipine was also found to decrease VSA by 17%±140% and 33% after 6 weeks, but further studies needed.

CONCLUSION

Diltiazem, nifedipine and amlodipine are potent in decreasing VSA, however, tailoring specific CCBs adverse reactions to patient condition and the drug preparation would be substantially beneficial for the outcome.

Vasospastic angina following COVID-19 vaccine-related myocarditis: an underlying cause of chest pain

We present a 13-year-old boy who had recurrent chest pain with elevated cardiac enzymes and abnormal ST segments in electrocardiogram 36 hours after the second dose of BNT162b2 vaccination. Cardiac MRI and coronary angiography with acetylcholine provocation confirmed myocarditis and vasospastic angina, respectively. Coronary vasospasm may play a pivotal role in the chest pain in COVID-19 vaccine-related myocarditis.

Coronary artery spasm treated with intracoronary bioresorbable scaffold implantation under the guidance of treadmill test and optical coherence tomography: A case report

Coronary artery spasm (CAS) can cause unstable angina, and the treatment of this disease is controversial. We report an elderly male patient who was admitted to hospital due to chest tightness. CAG showed that 70% stenosis in the middle of the right coronary artery (RCA). A bioresorbable scaffold (BRS) was implanted in the lesion under the guidance of optical coherence tomography (OCT). One year later, the patient's symptoms were relieved. The repeated CAG showed that the stent was good. BRS implantation under the guidance of treadmill test and OCT is one of treatment options for CAS patients.

Clinical Characteristics and Prognosis of Patients with Vasospastic Angina Subjected to the Spasm Provocation Test and the Unavoidable Use of Nitroglycerin

Background: Multi-vessel spasm (MVS) has a prognostic impact in patients with vasospastic angina (VSA). Thus, the presence of coronary spasm in both the left coronary artery (LCA) and right coronary artery (RCA) should be assessed through the spasm provocation test (SPT). Nitroglycerin (NTG) is used to avoid SPT-related complications; however, this unavoidable use of NTG may decrease the detection of MVS. Therefore, we investigated the frequency of the unavoidable use of NTG during SPT and clarified the clinical characteristics in patients with VSA who underwent the unavoidable use of NTG during STP. Methods: A total of 141 patients with positive SPT were evaluated. A positive SPT was defined as > 90% constriction in epicardial coronary arteries in response to acetylcholine, accompanied by the usual chest symptoms and/or ischaemic ST-T changes on electrocardiography. When a coronary spasm occurred, we usually wait for the spontaneous relief of the coronary spasm. However, if a prolonged coronary spasm or unstable haemodynamics occurred, 0.3 mg NTG was administered intracoronarily to promptly relieve the coronary spasm and this was defined as the unavoidable use of NTG. Even when the unavoidable use of NTG was administered in one coronary artery, an additional SPT was performed on another coronary artery. If a coronary spasm occurred in another coronary artery, a positive SPT was diagnosed. In contrast, if a coronary spasm was not induced after the unavoidable use of NTG, the judgement was classified as undiagnosed. The patients were divided into two groups according to the unavoidable use of NTG: U-NTG (n = 42) and the final use of NTG: F-NTG (n = 99). The clinical characteristics and frequencies of MVS (≥2 major coronary arteries in which a coronary spasm was provoked) and complications (malignant arrhythmia and unstable haemodynamics requiring catecholamines) during the SPT were compared between the groups. Results: Except for smoking status, all other clinical characteristics did not differ significantly between the groups. More current smokers were observed in the U-NTG group (29%) than in the F-NTG group (12%, p = 0.02). The frequency of MVS did not vary significantly between the groups (p = 0.28), with 64% for U-NTG and 55% for F-NTG. No significant difference was found between the groups in the frequency of severe complications during SPT (p = 0.83), with 2% for U-NTG and 3% for F-NTG. In the U-NTG group, the positive induction rate of coronary spasm in another coronary artery was 40% (17/42). Conclusions: The unavoidable use of NTG occurred in ~30% of patients with VSA, most of whom were current smokers. It did not decrease the detection of MVS and potentially prevented severe complications during SPT. Therefore, the unavoidable use of NTG is acceptable during SPT. However, an additional test may need to be performed to assess the presence of MVS.

The Importance of Integrated Regulation Mechanism of Coronary Microvascular Function for Maintaining the Stability of Coronary Microcirculation: An Easily Overlooked Perspective

Coronary microvascular dysfunction (CMD) refers to a group of disorders affecting the structure and function of coronary microcirculation and is associated with an increased risk of major adverse cardiovascular events. At present, great progress has been made in the diagnosis of CMD, but there is no specific treatment for it because of the complexity of CMD pathogenesis. Vascular dysfunction is one of the important causes of CMD, but previous reviews mostly considered microvascular dysfunction as a whole abnormality so the obtained conclusions are skewed. The coronary microvascular function is co-regulated by multiple mechanisms, and the mechanisms by which microvessels of different luminal diameters are regulated vary. The main purpose of this review is to revisit the mechanisms by which coronary microvessels at different diameters regulate coronary microcirculation through integrated sequential activation and briefly discuss the pathogenesis, diagnosis, and treatment progress of CMD from this perspective.

Slow-flow phenomenon after drug-coated balloon angioplasty for lower-extremity arteries is associated with lack of prescribing of calcium channel blockers

This study aimed to investigate the relationship between prescription drugs and the slow-flow phenomenon after drug-coated balloon angioplasty. Of 30 patients, five (17%) presented with the slow-flow phenomenon. Patients with the slow-flow phenomenon were significantly less commonly prescribed calcium channel blockers than those without the slow-flow phenomenon (P = 0.03). There was no intergroup difference in the prescription of angiotensin II receptor blockers and β-blockers. The clinical outcomes, including restenosis, thrombosis, target lesion revascularization, and death, did not differ between groups during the 10-month observation period.

Invasive coronary physiology in patients with angina and non-obstructive coronary artery disease: a consensus document from the coronary microvascular dysfunction workstream of the British Heart Foundation/National Institute for Health Research Partnership

Nearly half of all patients with angina have non-obstructive coronary artery disease (ANOCA); this is an umbrella term comprising heterogeneous vascular disorders, each with disparate pathophysiology and prognosis. Approximately two-thirds of patients with ANOCA have coronary microvascular disease (CMD). CMD can be secondary to architectural changes within the microcirculation or secondary to vasomotor dysfunction. An inability of the coronary vasculature to augment blood flow in response to heightened myocardial demand is defined as an impaired coronary flow reserve (CFR), which can be measured non-invasively, using imaging, or invasively during cardiac catheterisation. Impaired CFR is associated with myocardial ischaemia and adverse cardiovascular outcomes.The CMD workstream is part of the cardiovascular partnership between the British Heart Foundation and The National Institute for Health Research in the UK and comprises specialist cardiac centres with expertise in coronary physiology assessment. This document outlines the two main modalities (thermodilution and Doppler techniques) for estimation of coronary flow, vasomotor testing using acetylcholine, and outlines a standard operating procedure that could be considered for adoption by national networks. Accurate and timely disease characterisation of patients with ANOCA will enable clinicians to tailor therapy according to their patients' coronary physiology. This has been shown to improve patients' quality of life and may lead to improved cardiovascular outcomes in the long term.

Phenotype-based management of coronary microvascular dysfunction

40-70% of patients undergoing invasive coronary angiography with signs and symptoms of ischemia are found to have no obstructive coronary artery disease (INOCA). When this heterogeneous group undergo coronary function testing, approximately two-thirds have demonstrable coronary microvascular dysfunction (CMD), which is independently associated with adverse prognosis. There are four distinct phenotypes, or subgroups, each with unique pathophysiological mechanisms and responses to therapies. The clinical phenotypes are microvascular angina, vasospastic angina, mixed (microvascular and vasospastic), and non-cardiac symptoms (reclassification as non-INOCA). The Coronary Vasomotor Disorders International Study Group (COVADIS) have proposed standardized criteria for diagnosis. There is growing awareness of these conditions among clinicians and within guidelines. Testing for CMD can be done using invasive or non-invasive modalities. The CorMicA study advocates the concept of 'functional angiography' to guide stratified medical therapy. Therapies broadly fall into two categories: those that modulate cardiovascular risk and those to alleviate angina. Management should be tailored to the individual, with periodic reassessment for efficacy. Phenotype-based management is a worthy endeavor for both patients and clinicians, aligning with the concept of 'precision medicine' to improve prognosis, symptom burden, and quality of life. Here, we present a contemporary approach to the phenotype-based management of patients with INOCA.

Imaging of heart disease in women: review and case presentation

Cardiovascular diseases (CVD) remain the leading cause of mortality worldwide. Although major diagnostic and therapeutic advances have significantly improved the prognosis of patients with CVD in the past decades, these advances have less benefited women than age-matched men. Noninvasive cardiac imaging plays a key role in the diagnosis of CVD. Despite shared imaging features and strategies between both sexes, there are critical sex disparities that warrant careful consideration, related to the selection of the most suited imaging techniques, to technical limitations, and to specific diseases that are overrepresented in the female population. Taking these sex disparities into consideration holds promise to improve management and alleviate the burden of CVD in women. In this review, we summarize the specific features of cardiac imaging in four of the most common presentations of CVD in the female population including coronary artery disease, heart failure, pregnancy complications, and heart disease in oncology, thereby highlighting contemporary strengths and limitations. We further propose diagnostic algorithms tailored to women that might help in selecting the most appropriate imaging modality.

Implantable cardioverter-defibrillator therapy after resuscitation from cardiac arrest in vasospastic angina: A retrospective study

Patients with vasospastic angina (VSA) who are resuscitated from sudden cardiac arrest (SCA) are at a high risk of recurrent lethal arrhythmia and cardiovascular events. However, the benefit of the implantable cardioverter-defibrillator (ICD) therapy in this population has not been fully elucidated. The present study aimed to analyze the prognostic impact of ICD therapy on patients with VSA and SCA. A total of 280 patients who were resuscitated from SCA and received an ICD for secondary prophylaxis were included in the present multicenter registry. The patients were divided into two groups on the basis of the presence of VSA. The primary endpoint was a composite of all-cause death and appropriate ICD therapy (appropriate anti-tachycardia pacing and shock) for recurrent ventricular arrhythmias. Of 280 patients, 51 (18%) had VSA. Among those without VSA, ischemic cardiomyopathy was the main cause of SCA (38%), followed by non-ischemic cardiomyopathies (18%) and Brugada syndrome (7%). Twenty-three (8%) patients were dead and 72 (26%) received appropriate ICD therapy during a median follow-up period of 3.8 years. There was no significant difference in the incidence of the primary endpoint between patients with and without VSA (24% vs. 33%, p = 0.19). In a cohort of patients who received an ICD for secondary prophylaxis, long-term clinical outcomes were not different between those with VSA and those with other cardiac diseases after SCA, suggesting ICD therapy may be considered in patients with VSA and those with other etiologies who were resuscitated from SCA.

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.

The Impact of Myocardial Bridging on the Coronary Functional Test in Patients with Ischaemia with Non-Obstructive Coronary Artery Disease

Background: The possibility of myocardial bridging (MB) causing chest pain has been widely reported; however, the effect of MB on coronary microvessels has not been thoroughly investigated. Therefore, this study evaluated the effects of MB on epicardial coronary artery and coronary microvascular function during coronary angiography (CAG) and coronary function test (CFT) in patients with ischaemia with non-obstructive coronary artery disease (INOCA). Methods: This study included 62 patients with INOCA who underwent CAG and CFT for the left anterior descending coronary artery (LAD) to evaluate chest pain. In the CFT, acetylcholine was first administered intracoronarily in a stepwise manner, followed by chest symptoms, electrocardiographic ST-T changes and CAG. Positive coronary spasm was defined as coronary vasoconstriction of >90% on CAG accompanied by chest symptoms or electrocardiographic ST-T changes. After nitroglycerin administration, CAG was performed to assess MB, which was defined as systolic narrowing of the coronary artery diameter by >20% compared with that in diastole. Coronary flow reserve (CFR) and index of microcirculatory resistance (IMR) were subsequently obtained via transvenous adenosine triphosphate infusion using a pressure wire. Coronary microvascular vasodilatory dysfunction (CMD) was defined as a CFR of <2.0 or an IMR of ≥25 units. Results: Of the 62 patients, 15 (24%) had MB. The patients’ characteristics did not differ between the two groups. Regarding the CAG and CFT results, the presence of coronary spasm in the LAD was higher in the MB (+) group (87%) than in the MB (−) group (53%, p = 0.02), whereas the values of CFR (MB (+): 2.7 ± 1.4, MB (−): 2.8 ± 1.1) and IMR (MB (+): 26.9 ± 1.0, MB (−): 30.0 ± 17.3) and the presence of CMD (MB (+): 53%, MB (−): 60%) were similar in the two groups. Conclusions: The findings suggest that MB predisposes patients with INOCA to coronary spasms. Conversely, MBs may have a limited effect on microvessels, particularly in such patients.

Clinical Practice Variations in the Management of Ischemia With No Obstructive Coronary Artery Disease

Background Ischemia with no obstructive coronary artery disease is a condition associated with major adverse cardiovascular outcomes. To date, there are no specific American Heart Association or American College of Cardiology guidelines. The objective of this survey is to better understand the clinical practice and knowledge gaps that exist nationally. Methods and Results Participant-specific links for a survey with 11 questions and 3 reminders were sent between September and October 2020 to the American College of Cardiology CardioSurve Panel. The panel consist of randomly selected cardiologists (n=437) who represent the current profile of the American College of Cardiology US membership. The survey received a 30% response rate. Of the 172 respondents, 130 (76%) indicated that they have treated patients with ischemia with no obstructive coronary artery disease. Although the majority (69%) are generally confident in their ability to manage this condition, 1 of 3 report lack of confidence or are neutral. The American College of Cardiology/American Heart Association Chronic Stable Angina Guidelines are the most commonly used reference for treating ischemia with no obstructive coronary artery disease (81%), with most cardiologists wanting additional clinical guidance, such as randomized controlled trials (61%). More than 4 of 5 cardiologists rarely or never order advanced imaging modalities to assess coronary flow reserve. Approximately 2 of 3 of respondents frequently prescribe statins (68%), aspirin (66%), calcium channel blockers (63%), and β blockers or α/β blockers (55%). However, nearly 70% never prescribe angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. Conclusions This survey demonstrates heterogeneity in the management of ischemia with no obstructive coronary artery disease among US cardiologists, identifies support for guideline development, and outlines knowledge gaps for research and education in the therapeutic management of this condition.

A Simple Risk Score to Differentiate Between Coronary Artery Obstruction and Coronary Artery Spasm of Patients With Acute Coronary Syndrome Without Persistent ST-Segment Elevation

BACKGROUND

The aim of this study was to create a risk scoring model to differentiate obstructive coronary artery (CA) from CA spasm in the etioology of acute coronary syndrome (ACS).

METHODS AND RESULTS

We included 753 consecutive patients with ACS without persistent ST-segment elevation (p-STE). The exclusion criteria were: (1) out-of-hospital cardiac arrest; (2) cardiogenic shock; (3) hemodialysis; (4) atrial fibrillation/flutter; (5) severe valvular disease; (6) no coronary angiography; (7) non-obstructive coronary artery without "definite" vasospastic angina definition; and/or (8) missing data. From the multivariate logistic regression analysis for prediction of obstructive CA, an integer score of 2 to each 0.5 increment in odds ratio was given, and values were divided into quartiles according to the total score. The scores were as follows: age >70 years (6 points), non-STE myocardial infarction (9 points), diabetes mellitus (5 points), B-type natriuretic peptide >90 pg/mL (7 points), neutrophil to lymphocyte ratio >2 (5 points), and high-density lipoprotein cholesterol <50 mg/dL (5 points). CA spasm-induced ACS occurred in 50.0% in Quartile 1 (total score: 0-13), 20.5% in Quartile 2 (total score: 14-19), 4.9% in Quartile 3 (total score: 20-26), and 2.2% in Quartile 4 (total score: 27-37) (P<0.001), indicating that a total score of <20 was a potential clinical indicator of CA spasm-induced ACS.

CONCLUSIONS

CA spasm-induced ACS should be suspected if a total score of <20, and a spasm provocation test was being considered.

Clinical Outcomes and Provoked Epicardial Spasm Phenotypes via Intracoronary Acetylcholine Testing in 680 Patients with Angina and Nonobstructive Coronary Arteries

Background: Epicardial spasm (ES) phenotypes may be related to the prognosis in patients with coronary spastic angina. Objectives: The purpose of this study was to elucidate the relationship between angiographic coronary vasomotor responses to intracoronary acetylcholine (ACh) injection and prognosis in patients with angina and nonobstructive coronary artery disease (ANOCAD). Methods: This was a retrospective, observational, single-center study of 680 patients with ANOCAD. ACh spasm provocation tests on both coronary arteries were performed without administering nitroglycerine to relieve provoked spasm in a first-attempt artery. ACh was injected in incremental doses of 20/50/100/200 μg into the left coronary artery and 20/50/80 μg into the right coronary artery. Positive ES was defined as ≥90% stenosis and usual chest pain and ischemic ECG changes. Results: Provoked positive ES was observed in 310 patients (46%), including 85 patients (13%) with focal spasm, 150 patients (22%) with diffuse spasm, and 75 patients (11%) with combined spasm (diffuse spasm and focal spasm), whereas the remaining 370 patients (54%) had no provoked spasm. An unclassified ACh test was observed in 186 patients (27%), while 184 patients (27%) had a complete negative ACh test. The clinical outcomes in patients with complete negative ES were satisfactory compared with those with positive ES and unclassified ACh test results. The prognosis in patients with an unclassified ACh test was not different from those with a positive ES. Furthermore, prognosis in patients with ES phenotypes was not different among the three groups. Conclusions: There was no correlation between provoked ES phenotypes via intracoronary ACh testing and prognosis in patients with ANOCAD; however, clinical outcomes in patients with positive ES and unclassified ACh tests were worse compared to those with complete negative ACh tests. We should focus on the treatments in patients with unclassified ACh tests as well as those with ESs.

MINOCA: One Size Fits All? Probably Not—A Review of Etiology, Investigation, and Treatment

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a heterogeneous group of conditions that include both atherosclerotic (coronary plaque disruption) and non-atherosclerotic (spontaneous coronary artery dissection, coronary artery spasm, coronary artery embolism, coronary microvascular dysfunction, and supply–demand mismatch) causes resulting in myocardial damage that is not due to obstructive coronary artery disease. Failure to identify the underlying cause may result in inadequate and inappropriate therapy in these patients. The cornerstone of managing MINOCA patients is to identify the underlying mechanism to achieve the target treatment. Intravascular imaging is able to identify different morphologic features of coronary plaques, while cardiac magnetic resonance is the gold standard for detection of myocardial infarction in the setting of MINOCA. In this review, we summarize the relevant clinical issues, contemporary diagnosis, and treatment options of MINOCA.

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.

Vasospastic Angina: A Contemporary Review of its Pathophysiology, Diagnosis and Management

Nearly 40% of patients presenting to the catheter laboratory with angina have non-obstructed coronary arteries (ANOCA), an umbrella term that encompasses distinct pathophysiological entities, such as coronary artery spasm. Coronary artery spasm leads to sudden reversible coronary flow attenuation, which clinically manifests as vasospastic angina (VSA). VSA is associated with poor quality of life and an increased risk of major adverse cardiac events. However, the pathophysiological mechanisms underlying this phenomenon are incompletely understood, which has resulted in limited therapeutic options for patients afflicted with this condition. The past decade has seen a surge in new research being conducted in the field of ANOCA and VSA. This review article provides a comprehensive summary of the underlying pathophysiological mechanisms of VSA and the current therapeutic options. We also appraise the current diagnostic approach in patients with suspected VSA.

Perspectives in noninvasive imaging for chronic coronary syndromes

Both the latest European guidelines on chronic coronary syndromes and the American guidelines on chest pain have underlined the importance of noninvasive imaging to select patients to be referred to invasive angiography. Nevertheless, although coronary stenosis has long been considered the main determinant of inducible ischemia and symptoms, growing evidence has demonstrated the importance of other underlying mechanisms (e.g., vasospasm, microvascular disease, energetic inefficiency). The search for a pathophysiology-driven treatment of these patients has therefore emerged as an important objective of multimodality imaging, integrating "anatomical" and "functional" information. We here provide an up-to-date guide for the choice and the interpretation of the currently available noninvasive anatomical and/or functional tests, focusing on emerging techniques (e.g., coronary flow velocity reserve, stress-cardiac magnetic resonance, hybrid imaging, functional-coronary computed tomography angiography, etc.), which could provide deeper pathophysiological insights to refine diagnostic and therapeutic pathways in the next future.

Assessment of coronary spasms with transluminal attenuation gradient in coronary computed tomography angiography

Purpose

To evaluate the imaging features of coronary spasm, including transluminal attenuation gradient (TAG) on coronary computed tomography angiography (CCTA), in patients with vasospastic angina (VA).

Methods

A total of 43 patients with a high clinical likelihood of VA were included in the study. All the subjects underwent double CCTA acquisition: CCTA without a vasodilator (‘baseline CT’) and CCTA during continuous intravenous nitrate infusion (‘IV nitrate CT’). A catheterized ergonovine provocation test was used to determine true VA patients. Coronary spasm is classified into focal- and diffuse-types according to morphological differences. We measured TAG and contrast enhancement of the proximal ostium (ProxHU) of each coronary artery for both the baseline and IV nitrate CT.

Results

Twenty-four patients (55.8%) showed positive results of coronary vasospasm on the provocation test. Thirty-eight vessels showed coronary spasms (29.5%): Focal-type in nine vessels (24%), and diffuse-type in 29 (76%). In the baseline CT, LCX showed significantly lower (steeper) TAG in spasm(+) vessels than in spasm(-) vessels, while LAD and RCA showed no significant differences in TAG. The ProxHU of LAD showed significantly lower values in spasm(+) vessels than in spasm(-) vessels, while the other vessels did not show significant differences in ProxHU. For IV nitrate CT, there were no significant differences in either the TAG and ProxHU between spasm(+) and (-) vessels for all the three vessel types. In subgroup analysis for spasm(+) vessels, diffuse spasms showed significantly lower TAG than focal spasms, while the ProxHU did not differ between the two types of spasm.

Conclusions

A relatively large percentage of coronary spasms present as diffuse type, and the TAG values significantly differed according to the morphological type of the coronary spasm.

Clinical Characteristics and Prognosis of Patients with Multi-Vessel Coronary Spasm in Comparison with Those in Patients with Single-Vessel Coronary Spasm

(1) Background: We have sometimes experienced patients with vasospastic angina (VSA) who presented multi-vessel spasm (MVS) on coronary angiography and spasm provocation test (SPT). However, the clinical characteristics of VSA patients with MVS and the prognosis of such patients in the clinical setting have not been clarified. Therefore, we compared the clinical characteristics and prognosis in VSA patients with MVS with those in VSA patients with single-vessel spasm (SVS). (2) Methods: A total of 152 patients (mean age, 67 years, 74 men and 78 women) with VSA, in which the presence of coronary spasm was assessed in both left coronary artery (LCA) and right coronary artery (RCA) on SPT, were enrolled. We defined VSA as the presence of >90% narrowing of the epicardial coronary artery on angiograms, accompanied by usual chest symptoms and/or ischaemic ST-T changes on the electrocardiogram. On SPT, MVS was defined as the presence of spasms on ≥2 major coronary arteries. Based on the presence of MVS, patients were divided into the MVS group and the SVS group. The frequencies of conventional coronary risk factors, blood chemical parameters, average times of anginal attack, SPT findings such as spasm provocation induced by a low dose of acetylcholine (L-ACh) and total occlusion due to coronary spasm (TOC), number of coronary vasodilators at discharge and major cardiovascular events (MACE, including cardiac death and readmission due to any cause of cardiovascular diseases) were compared between the two groups. (3) Results: The MVS and SVS groups were comprised of 98 (64%) and 54 (36%) patients, respectively. The level of fasting blood glucose (FBS) was lower (p < 0.01), and the level of cystatin-C (n = 89) tended to be higher (p = 0.07) in the MVS group than in the SVS group. The frequencies of L-ACh-induced coronary spasm (33% in MVS and 17% in SVS, p = 0.04) and TOC (12% in MVS, 0% in SVS, p < 0.01) were higher in the MVS group than in the SVS group. The average number of coronary vasodilators at discharge was higher in the MVS group (1.2 ± 0.4) than in the SVS group (0.9 ± 0.5, p < 0.01). The frequency of MACE was not different between the two groups. (4) Conclusions: Patients with MVS may have higher VSA activity on SPT and have more aggressive medications, leading to a comparable prognosis in VSA patients with SVS. MVS is an important indicator of at least VSA activity, and cardiologists should confirm this in SPT whenever possible. Further studies should confirm whether lower FBS levels and higher cystatin-C levels are any markers of MVS.

Safety of Provocative Testing With Intracoronary Acetylcholine and Implications for Standard Protocols

BACKGROUND

Heterogeneity in diagnostic criteria and provocation protocols has posed challenges in understanding the safety of coronary provocation testing with intracoronary acetylcholine (ACh) for the contemporary diagnosis of epicardial and microvascular spasm.

OBJECTIVES

We examined the safety of testing and subgroup differences in procedural risks based on ethnicity, diagnostic criteria, and provocation protocols.

METHODS

PubMed and Embase were searched in November 2021 to identify original articles reporting procedural complications associated with intracoronary ACh administration. The primary outcome was the pooled estimate of the incidence of major complications including death, myocardial infarction, ventricular tachycardia/fibrillation, and shock.

RESULTS

A total of 16 studies with 12,585 patients were included in the meta-analysis. The overall pooled estimate of the incidence of major complications was 0.5% (95% CI: 0.0%-1.3%) without any reports of death. Exploratory subgroup analyses revealed that the pooled incidence of major complications was significantly higher in the studies that followed the contemporary diagnosis criteria for epicardial spasm defined as ≥90% diameter reduction (1.0%; 95% CI: 0.3%-2.0%) but significantly lower in Western populations (0.0%; 95% CI: 0.0%-0.45%). The rate of positive epicardial spasm and the incidence of major complications were similar between provocation protocols using the maximum ACh doses of 100 μg and 200 μg.

CONCLUSIONS

Intracoronary ACh administration for the contemporary diagnosis of epicardial and microvascular spasm is a safe procedure. Moreover, excellent safety records are observed in Western populations primarily presenting with myocardial ischemia and/or infarction with nonobstructive coronary arteries. This study will help standardize ACh testing to improve clinical diagnosis and ensure procedural safety.

Tacrolimus-Induced Diffuse Coronary Artery Spasm

Prinzmetal angina, also known as vasospastic angina, is defined as an intermittent focal or diffuse coronary artery narrowing, which is often associated with transient ST-segment elevation on an electrocardiogram. Also, it could be associated with an atherosclerotic lesion at the site of the spasm. Vasospastic angina might be induced by medications, most commonly with cocaine and other examples which include catecholamines such as epinephrine, norepinephrine, isoproterenol, dopamine, and dobutamine. Parasympathomimetic agents include acetylcholine, methacholine, and pilocarpine. It is rarely caused by tacrolimus. The clinical evaluation includes an electrocardiogram and echocardiogram. The confirmed diagnosis is done by coronary angiography. Cardiac catheterization is indicated in such cases to rule out coronary artery disease.

Nitrates vs. Other Types of Vasodilators and Clinical Outcomes in Patients with Vasospastic Angina: A Propensity Score-Matched Analysis

Although vasodilators are widely used in patients with vasospastic angina (VA), few studies have compared the long-term prognostic effects of different types of vasodilators. We investigated the long-term effects of vasodilators on clinical outcomes in VA patients according to the type of vasodilator used. Study data were obtained from a prospective multicenter registry that included patients who had symptoms suggestive of VA. Patients were classified into two groups according to use of nitrates (n = 239) or other vasodilators (n = 809) at discharge. The composite clinical events rate, including acute coronary syndrome (ACS), cardiac death, new-onset arrhythmia (including ventricular tachycardia and ventricular fibrillation), and atrioventricular block, was significantly higher in the nitrates group (5.3% vs. 2.2%, p = 0.026) during one year of follow-up. Specifically, the prevalence of ACS was significantly more frequent in the nitrates group (4.3% vs. 1.5%, p = 0.024). After propensity score matching, the adverse effects of nitrates remained. In addition, the use of nitrates at discharge was independently associated with a 2.69-fold increased risk of ACS in VA patients. In conclusion, using nitrates as a vasodilator at discharge can increase the adverse clinical outcomes in VA patients at one year of follow-up. Clinicians need to be aware of the prognostic value and consider prescribing other vasodilators.

Perioperative coronary artery spasms in patients undergoing catheter ablation of atrial fibrillation

PURPOSE

Catheter ablation (CA) is an established treatment for atrial fibrillation (AF). Although coronary artery spasms (CAS) during or after ablation procedures have been described as a rare complication in some case reports, the incidence and characteristics of this complication have not been fully elucidated. The present observational study aimed to clarify the CAS in a large number of patients experiencing AF ablation.

METHODS

A total of 2913 consecutive patients (male: 78%, mean 66 ± 10 years) who underwent catheter ablation of AF were enrolled.

RESULTS

Nine patients (0.31%, mean 66 ± 10 years, 7 males) had transient ST-T elevation (STE). Eight out of the 9 patients had STE in the inferior leads. STE occurred after the transseptal puncture in 7 patients, after the sheath was pulled out of the left atrium in 1, and 2 h after the ablation procedure in 1. Six patients had definite angiographic CAS without any sign of an air embolization on the emergent coronary angiography. In the3 other patients, the STE improved either directly after an infusion of nitroglycerin or spontaneously before the CAG. The patients with CAS had a higher frequency of a smoking habit (89% vs. 53%; P = .04), smaller left atrial diameter (36 ± 6 vs. 40 ± 7; P = .07), and lower CHADS2 score (0.6 ± 0.5 vs. 1.3 ± 1.1; P = .004) than those without.

CONCLUSIONS

Although the incidence was rare (0.31%), CAS should be kept in mind as a potentially life-threatening complication throughout an AF ablation procedure especially performed under conscious sedation.

Coronary artery spasm due to acute myocarditis in an adolescent: a case report

BACKGROUND

Myocarditis refers to the inflammation of the myocardium caused by infection or autoimmune disease that may or may not present with clinical manifestations, such as gastrointestinal symptoms, dyspnea, chest pain, or sudden death. Although myocarditis and coronary artery vasospasm may mimic ST-segment elevation myocardial infarction (STEMI) with normal coronary arteries on angiography, acute myocarditis rarely causes coronary artery spasm. Here, we report a case of coronary artery spasm with reversible electrocardiographic changes mimicking STEMI in an adolescent with acute myocarditis.

CASE PRESENTATION

A 15-year-old boy present with sudden-onset repeated chest pain following a 3-day history of flu-like illness. Cardiac biomarkers were significantly elevated. Electrocardiography showed ST-segment elevation in the absence of detectable vasospasm on coronary angiography. These findings were consistent with the diagnosis of coronary artery spasm secondary to acute myocarditis. Treatment with immunoglobulin for 2 days improved his condition. The patient was discharged on the 12th day with complete resolution of symptoms and normalization of electrocardiogram findings.

CONCLUSIONS

We reported a case of coronary artery spasm due to acute myocarditis. This study highlights the importance of considering coronary artery spasm due to acute myocarditis as a differential diagnosis in patients presenting with signs of STEMI as these diseases have different medical management strategies.

A Practical Approach to Invasive Testing in Ischemia with No Obstructive Coronary Arteries (INOCA)

Up to 65% of women and approximately 30% of men have ischemia with no obstructive coronary artery disease (CAD; commonly known as INOCA) on invasive coronary angiography performed for stable angina. INOCA can be due to coronary microvascular dysfunction or coronary vasospasm. Despite the absence of obstructive CAD, those with INOCA have an increased risk of all-cause mortality and adverse outcomes, including recurrent angina and cardiovascular events. These patients often undergo repeat testing, including cardiac catheterization, resulting in lifetime healthcare costs that rival those for obstructive CAD. Patients with INOCA often remain undiagnosed and untreated. This review discusses the symptoms and prognosis of INOCA, offers a systematic approach to the diagnostic evaluation of these patients, and summarizes therapeutic management, including tailored therapy according to underlying pathophysiological mechanisms.

Clinical Relevance of Ischemia with Nonobstructive Coronary Arteries According to Coronary Microvascular Dysfunction

Background

In the absence of obstructive coronary stenoses, abnormality of noninvasive stress tests (NIT) in patients with chronic coronary syndromes may indicate myocardial ischemia of nonobstructive coronary arteries (INOCA). The differential prognosis of INOCA according to the presence of coronary microvascular dysfunction (CMD) and incremental prognostic value of CMD with intracoronary physiologic assessment on top of NIT information remains unknown.

Methods and Results

From the international multicenter registry of intracoronary physiologic assessment (ILIAS [Inclusive Invasive Physiological Assessment in Angina Syndromes] registry, N=2322), stable patients with NIT and nonobstructive coronary stenoses with fractional flow reserve >0.80 were selected. INOCA was diagnosed when patients showed positive NIT results. CMD was defined as coronary flow reserve ≤2.5. According to the presence of INOCA and CMD, patients were classified into 4 groups: group 1 (no INOCA nor CMD, n=116); group 2 (only CMD, n=90); group 3 (only INOCA, n=41); and group 4 (both INOCA and CMD, n=40). The primary outcome was major adverse cardiovascular events, a composite of all‐cause death, target vessel myocardial infarction, or clinically driven target vessel revascularization at 5 years. Among 287 patients with nonobstructive coronary stenoses (fractional flow reserve=0.91±0.06), 81 patients (38.2%) were diagnosed with INOCA based on positive NIT. By intracoronary physiologic assessment, 130 patients (45.3%) had CMD. Regardless of the presence of INOCA, patients with CMD showed a significantly lower coronary flow reserve and higher hyperemic microvascular resistance compared with patients without CMD (P<0.001 for all). The cumulative incidence of major adverse cardiovascular events at 5 years were 7.4%, 21.3%, 7.7%, and 34.4% in groups 1 to 4. By documenting CMD (groups 2 and 4), intracoronary physiologic assessment identified patients at a significantly higher risk of major adverse cardiovascular events at 5 years compared with group 1 (group 2: adjusted hazard ratio [HR_adjusted], 2.88; 95% CI, 1.52–7.19; P=0.024; group 4: HR_adjusted, 4.00; 95% CI, 1.41–11.35; P=0.009).

Conclusions

In stable patients with nonobstructive coronary stenoses, a diagnosis of INOCA based only on abnormal NIT did not identify patients with higher risk of long‐term cardiovascular events. Incorporating intracoronary physiologic assessment to NIT information in patients with nonobstructive disease allowed identification of patient subgroups with up to 4‐fold difference in long‐term cardiovascular events.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04485234.

Vasospasm-induced ST-segment elevation myocardial infarction in a premenopausal woman with endothelial dysfunction

ST-segment elevation myocardial infarction (STEMI) can be caused by coronary artery vasospasm (VSA) due to endothelial dysfunction. However, the clinical role of endothelial function tests in VSA-induced STEMI is not fully understood. We present the case of a 43-year-old woman with atypical chest pain and no coronary risk factors. STEMI caused by VSA was diagnosed. Flow-mediated vasodilatation (FMD) and EndPAT tests were performed; the FMD and reactive hyperaemia index were 3.8% and 1.23, respectively. Endothelial dysfunction is the putative cause of STEMI. FMD and EndPAT tests might be useful for predicting adverse outcomes in young premenopausal women with VSA.

Acute myeloid leukemia causing acute thrombosis of the coronary arteries: a case report

Background

This case report demonstrates acute myeloid leukemia causing acute thrombosis of coronary arteries with anterolateral ST elevation myocardial infarction and ventricular tachycardia in an otherwise healthy woman. Few case reports have been documented on patients with concomitant conditions of acute myeloid leukemia and acute myocardial infarction, and it is important to note that prognosis for patients with both is worse than that of either condition. While both conditions together are rare, other non-atherosclerotic causes of acute coronary syndromes are likewise important considerations in the context of myocardial ischemia.

Case presentation

A 59-year-old Caucasian woman with no notable past medical history presented to her primary care provider with 2 weeks of severe fatigue, anorexia, and malaise, associated with chills, night sweats, and myalgias. Peripheral blood smear identified 92% blasts consistent with acute myeloid leukemia and computed tomography identified a right segmental pulmonary embolism and thrombotic infarcts in the spleen, bilateral kidneys, right lung, and liver. Laboratory testing also demonstrated disseminated intravascular coagulopathy. She was admitted to the intensive care unit for treatment and subsequently developed ventricular tachycardia, anterolateral ST segment elevation, acute dysarthria, and nonreactive pupils. Pulseless electrical activity developed with unsuccessful resuscitative measures. The patient died secondary to presumed cerebrovascular and coronary thromboses causing stroke and anterolateral infarct complicated by ventricular tachycardia and pulseless electrical activity.

Conclusion

This case is notable as a case of acute myeloid leukemia causing acute thrombosis of coronary arteries with anterolateral ST elevation myocardial infarction, ventricular tachycardia, and pulseless electrical activity. Prognosis of concomitant acute myeloid leukemia and acute myocardial infarction is poor. Management is challenging due to thrombocytopenia, platelet dysfunction, and systemic coagulopathy, and administration of thrombolytic agents can be fatal. This is an extreme presentation of a case of acute myocardial infarction with disseminated intravascular coagulopathy causing acute coronary thrombosis and sudden death with dramatic electrocardiogram and telemetry findings recorded with rapid progression from normal sinus rhythm to acute myocardial infarction to terminal rhythm.

Discharge disposition and 1-year readmission in acute-phase hospitalized patients with heart failure: a retrospective observational multi-center study

Patients hospitalized for acute heart failure (HF) tend to experience declines in physical function and activities of daily living (ADL) due to bed rest and restricted mobilization. This could result in some patients being transferred to rehabilitation hospitals. This study aims to examine the relationship between discharge disposition and 1-year readmission and mortality rates in HF patients. Nine hundred fifty six consecutive HF patients who were hospitalized for acute decompensated HF and underwent rehabilitation were divided into two groups: home (returned home) or transfer (transferred to rehabilitative or long-term care hospital units due to decline in physical function and/or ADL) groups. The primary and secondary outcomes were 1-year readmission and mortality rates after discharge, respectively. Of the 956 patients, 8.6% (n = 82) were transferred to rehabilitative or long-term care hospital units. Over a 1-year follow-up period, all-cause and HF readmission rates were 50.1% (n = 479) and 27.2% (n = 260), respectively. The transfer group had significantly lower readmission rates compared to home group after adjusting for the pre-existing risk factors (hazard ratio for all-cause and HF readmission: 0.600 and 0.552, 95% CI 0.401-0.897 and 0.314-0.969; P = 0.013 and P = 0.038, respectively). There was no significant relationship between discharge disposition and all-cause mortality rate. Low ADL defined as Barthel index < 60 points was identified as a predictor of all-cause and HF readmission among the home group (odds ratio for all-cause and HF readmission rates: 2.156 and 1.847, 95% CI 1.026-4.531 and 1.036-2.931; P = 0.043 and P = 0.037, respectively). This multi-center study demonstrated that HF patients transferred to rehabilitative or long-term care hospital units after an acute hospitalization had a significantly decreased 1-year all-cause and HF readmission rates compared to patients who returned to their home. These findings may help in selecting a discharge disposition for older HF patients with ADL decline.

Efficacy of Diltiazem to Improve Coronary Vasomotor Dysfunction in ANOCA: The EDIT-CMD Randomized Clinical Trial

OBJECTIVES

The randomized, placebo-controlled EDIT-CMD (Efficacy of Diltiazem to Improve Coronary Microvascular Dysfunction: A Randomized Clinical Trial) evaluated the effect of diltiazem on coronary vasomotor dysfunction (CVDys), as assessed by repeated coronary function testing (CFT), angina, and quality of life.

BACKGROUND

Diltiazem is recommended and frequently prescribed in patients with angina and nonobstructive coronary artery disease (ANOCA), suspected of CVDys. However, studies substantiating its effect is this patient group are lacking.

METHODS

A total of 126 patients with ANOCA were included and underwent CFT. CVDys, defined as the presence of vasospasm (after intracoronary acetylcholine provocation) and/or microvascular dysfunction (coronary flow reserve: <2.0, index of microvascular resistance: ≥25), was confirmed in 99 patients, of whom 85 were randomized to receive either oral diltiazem or placebo up to 360 mg/d. After 6 weeks, a second CFT was performed. The primary end point was the proportion of patients having a successful treatment, defined as normalization of 1 abnormal parameter of CVDys and no normal parameter becoming abnormal. Secondary end points were changes from baseline to 6-week follow-up in vasospasm, index of microvascular resistance, coronary flow reserve, symptoms (Seattle Angina Questionnaire), or quality of life (Research and Development Questionnaire 36).

RESULTS

In total, 73 patients (38 diltiazem vs 35 placebo) underwent the second CFT. Improvement of the CFT did not differ between the groups (diltiazem vs placebo: 21% vs 29%; P = 0.46). However, more patients on diltiazem treatment progressed from epicardial spasm to microvascular or no spasm (47% vs 6%; P = 0.006). No significant differences were observed between the diltiazem and placebo group in microvascular dysfunction, Seattle Angina Questionnaire, or Research and Development Questionnaire 36.

CONCLUSIONS

This first performed randomized, placebo-controlled trial in patients with ANOCA showed that 6 weeks of therapy with diltiazem, when compared with placebo, did not substantially improve CVDys, symptoms, or quality of life, but diltiazem therapy did reduce prevalence of epicardial spasm. (Efficacy of Diltiazem to Improve Coronary Microvascular Dysfunction: A Randomized Clinical Trial [EDIT-CMD]; NCT04777045).

Prognostic Impact of Chronic Vasodilator Therapy in Patients With Vasospastic Angina

Background

Chronic vasodilator therapy with long‐acting nitrate is frequently used to treat vasospastic angina. However, the clinical benefits of this approach are controversial. We investigated the prognostic impact of vasodilator therapy in patients with vasospastic angina from the multicenter, prospective VA‐KOREA (Vasospastic Angina in KOREA) registry.

Methods and Results

We analyzed data from 1895 patients with positive intracoronary ergonovine provocation test results. The patients were divided into 4 groups: no vasodilator (n=359), nonnitrate vasodilator (n=1187), conventional nitrate (n=209), and a combination of conventional nitrate and other vasodilators (n=140). The primary end point was a composite of cardiac death, acute coronary syndrome, and new‐onset arrhythmia at 2 years. Secondary end points were the individual components of the primary end point, all‐cause death, and rehospitalization due to recurrent angina.

The groups did not differ in terms of the risk of the primary end point. However, the acute coronary syndrome risk was significantly higher in the conventional nitrate (hazard ratio [HR], 2.49; 95% CI, 1.01–6.14; P=0.047) and combination groups (HR, 3.34; 95% CI, 1.15–9.75, P=0.027) compared with the no‐vasodilator group, as assessed using the inverse probability of treatment weights. Subgroup analyses revealed prominent adverse effects of nitrate in patients with an intermediate positive ergonovine provocation test result and in those with low Japanese Coronary Spasm Association scores.

Conclusions

Long‐acting nitrate‐based chronic vasodilator therapy was associated with an increased 2‐year risk of acute coronary syndrome in patients with vasospastic angina, especially in low‐risk patients.

Layered Plaque in Organic Lesions in Patients With Coronary Artery Spasm

Background

Coronary artery spasm plays a vital role in the pathogenesis of coronary plaques. We sought to investigate the plaque characteristics of co‐existing organic lesions in patients with coronary artery spasm in comparison to those without coronary artery spasm by intracoronary optical coherence tomography (OCT).

Methods and Results

We included 39 patients who presented with a symptom suspected of coronary spastic angina and had an organic lesion, defined as ≥plaque burden of 50% assessed by OCT. Coronary artery spasm was diagnosed by positive acetylcholine provocation test, or by spontaneous spasm detected during coronary angiography. A total of 51 vessels with an organic lesion were identified. Of these, coronary artery spasm was observed in 30 vessels (spasm), while not in 21 vessels (non‐spasm). Organic lesions in the spasm vessels, compared with those in the non‐spasm vessels, had a higher prevalence of layered plaque (93% versus 38%, P<0.001), macrophages (80% versus 43%, P=0.016), and intraplaque microchannels (73% versus 24%, P<0.001), and lower prevalence of macrocalcification (23% versus 62%, P=0.009) as assessed by OCT.

Conclusions

Layered plaque, macrophages, and intraplaque microchannels, were frequently observed in organic lesions in patients with coronary artery spasm. These findings suggest that coronary artery spasm induces local thrombus formation as well as active inflammatory response, therefore increasing the risk of rapid plaque progression and ischemic events in patients with coronary artery spasm.

Resistive reserve ratio and microvascular resistance reserve in patients with coronary vasospastic angina

Patients with epicardial coronary vasospastic angina (VSA) may be likely to have coronary microvascular dysfunction, although mixed results have been reported. The aim of this study was to evaluate coronary microvascular function in detail using novel invasive physiologic indices, such as resistive reserve ratio (RRR) and microvascular resistance reserve (MRR). A total of 45 patients undergoing intracoronary acetylcholine (ACh) provocation test and invasive coronary circulatory evaluation using a thermodilution method were prospectively included. VSA was diagnosed as angiographic vasospasm accompanied by chest pain and/or ischemic electrocardiographic changes by intracoronary injection of ACh. Coronary circulation was assessed with physiologic indices including fractional flow reserve, resting and hyperemic mean transit time (Tmn), coronary flow reserve (CFR), basal resistance index, index of microcirculatory resistance (IMR), RRR, and MRR. Of 45 patients, 23 (51.1%) were diagnosed as having VSA. Patients with positive ACh test had longer resting Tmn (slower coronary flow velocity), higher basal resistance index, and greater RRR and MRR than those without, while fractional flow reserve, CFR, and IMR did not differ significantly between the two groups. In conclusion, although conventional measures such as CFR and IMR failed to show significant differences, RRR and MRR, novel invasive coronary physiologic indices, provided counterintuitive insights that coronary microvascular dilation function was better preserved in patients with VSA than those without.

Spontaneous Multivessel Coronary Spasm During Diagnostic Coronary Angiography

Acute vasospastic angina, formerly known as Prinzmetal angina, is characterized by transient electrocardiographic changes that are not related to exertion. Its atypical presentation makes it difficult to establish the diagnosis, so it is probably underrecognized and therefore mismanaged. We treated a 49-year-old woman who presented with a 2-day history of chest pain associated with palpitations. Abnormal radionuclide stress test results prompted diagnostic coronary angiography, during which the patient reported chest pain and became hemodynamically unstable. Active coronary vasospasm at multiple sites was treated with intracoronary nitroglycerin and nicardipine, leading to immediate recovery. Our case highlights the importance of accurate, timely diagnosis of vasospastic angina, and of early recognition and management of spontaneous coronary spasm during angiography.

Acetylcholine Use in Modern Cardiac Catheterization Laboratories: A Systematic Review

BACKGROUND

The use of acetylcholine for the diagnosis of vasospastic angina is recommended by international guidelines. However, its intracoronary use is still off-label due to the absence of safety studies. We aimed to perform a systematic review of the literature to identify adverse events related to the intracoronary administration of acetylcholine for vasoreactivity testing to fill this gap.

METHODS AND RESULTS

We conducted a systematic review of observational studies and randomized controlled trials dealing with the intracoronary administration of acetylcholine. Articles were searched in MEDLINE (PubMed) using the MeSH strategy. Three independent reviewers determined whether the studies met the inclusion and exclusion criteria. A total of 434 articles were selected. Data concerning clinical characteristics, study population, acetylcholine dosage, and adverse effects were retrieved from the articles. Overall, 71,566 patients were included, of which only 382 (0.5%) developed one adverse event, and there were no fatal events reported (0%).

CONCLUSIONS

Intracoronary administration of acetylcholine in the setting of coronary spasm provocation testing is safe and plays a central role in the evaluation of coronary vasomotion disorders, making it worthy of becoming a part of clinical practice in all cardiac catheterization laboratories.

Principles and pitfalls in coronary vasomotor function testing

BACKGROUND

Coronary vasomotor dysfunction can be diagnosed in a large proportion of patients with angina in the presence of non-obstructive coronary artery disease (ANOCA) using comprehensive protocols for coronary vasomotor function testing (CFT). Although consensus on diagnostic criteria for endotypes of coronary vasomotor dysfunction has been published, consensus on a standardised study testing protocol is lacking.

AIMS

In this review we provide an overview of the variations in CFT used and discuss the practical principles and pitfalls of CFT.

METHODS

For the purposes of this review, we assessed study protocols that evaluate coronary vasomotor response as reported in the literature. We compared these protocols regarding a number of procedural aspects and chose six examples to highlight the differences and uniqueness.

RESULTS

Currently, numerous protocols co-exist and vary in vascular domains tested, the manner in which to test these domains (e.g., preprocedural discontinuation of medication, provocative agent, solution, infusion time, and target artery) and techniques used for measurements (e.g., Doppler vs thermodilution technique).

CONCLUSIONS

This lack of consensus on a uniform functional testing protocol hampers both a broader clinical acceptance of the concepts of coronary vasomotor dysfunction, and the widespread adoption of such testing protocols in current clinical practice. Furthermore, the endotype of coronary vasomotor dysfunction might differ among the few specialised centres that perform CFT as a result of the use of different protocols.

Fragmented QRS as a risk marker for the occurrence of ventricular fibrillation in patients with variant angina

BACKGROUND

Variant angina (VA) is caused by reversible coronary artery spasm, which is characterized by chest pain with ST-segment elevations on standard 12-lead electrocardiogram (ECG) at rest. Ventricular fibrillation (VF) is often caused by VA attack, but the risk stratification is not well understood. The purpose of this study was to evaluate the impact of fragmented QRS (fQRS) on VF occurrence in VA patients.

METHODS

Ninety-four patients who showed ST elevation on 12-lead ECGs with total or nearly total occlusion in response to coronary spasm provocation test were enrolled. Among them, 16 patients had documented VF before hospital admission (n = 12) or experienced VF during provocation test (n = 4) (VF occurrence group). The fQRS was defined as the presence of spikes within the QRS complex of two or more consecutive leads.

RESULTS

The prevalence of fQRS was more often observed in the VF occurrence group than in the non-VF occurrence group (63% [10/16] vs. 27% [21/78], p = 0.009). Univariate analyses revealed that age, history of syncope, QTc, and the presence of fQRS were associated with VF occurrence (p = 0.004, 0.005, 0.029, and 0.008, respectively). Furthermore, upon multivariate analyses using those risk factors, age, QTc, and fQRS predicted VF occurrence independently (p = 0.007, 0.041, and 0.014, respectively).

CONCLUSIONS

The present study demonstrated that fQRS in VA patients is a risk factor for VF. The fQRS may be a useful factor for the risk stratification of VF occurrence in VA patients.

Isolated cardiac sarcoidosis associated with coronary vasomotion abnormalities: a case report

Background 

Cardiac sarcoidosis is a chronic, inflammatory disease that can affect the heart and often results in heart failure and lethal arrhythmias. A multimodality imaging approach without endomyocardial biopsy allows for the diagnosis of isolated cardiac sarcoidosis. Coronary vasomotion abnormalities are highly prevalent in various cardiovascular and inflammatory diseases. It remains unknown whether active myocardial inflammation due to cardiac sarcoidosis is associated with coronary vasomotion abnormalities.

Case summary 

A 68-year-old man without a past medical history experienced an out-of-hospital cardiac arrest due to ventricular fibrillation and was successfully resuscitated without neurologic sequelae. Coronary angiography showed normal coronary arteries; however, intracoronary acetylcholine provocation testing demonstrated both epicardial coronary and coronary microvascular spasm. He was diagnosed with isolated cardiac sarcoidosis by fulfilling the diagnostic criteria proposed by the Japanese Circulation Society 2016 diagnostic guidelines, including fatal ventricular arrhythmia, focal left ventricular wall asynergy, increased myocardial fluorodeoxyglucose uptake by positron emission tomography, and late gadolinium enhancement by cardiac magnetic resonance in the heart. He was treated with calcium-channel blocker for coronary artery spasm and prednisolone for cardiac sarcoidosis and underwent implantation of an implantable cardioverter-defibrillator for secondary prevention. Following the treatment, the severity of coronary artery spasm was reduced along with regression of the myocardial inflammation.

Discussion 

Epicardial coronary artery and coronary microvascular spasm can be accompanied by active myocardial inflammation of isolated cardiac sarcoidosis, and the treatment with corticosteroid and calcium-channel blocker may be effective for relieving the severity of coronary artery spasm in association with regression of myocardial inflammation of the disease.

5-Fluorouracil, capecitabine and vasospasm: a scoping review of pathogenesis, management options and future research considerations

BACKGROUND

5-Fluorouracil (5-FU) is a widely used chemotherapeutic agent that can cause cardiotoxicity manifesting, among others, as chest pain. Capecitabine is an oral prodrug of 5-FU, with reported preferential activation in malignant cells that may also cause cardiotoxic reactions. Standard treatment of 5-FU and capecitabine induced chest pain with vasodilators is mostly effective, but there are several cases of patients unresponsive to these agents.

METHODS

We performed a PubMed search on 31st May 2020. We used a three keyword search strategy using Boolean search operators. More specifically, we included fluorouracil or 5-FU or capecitabine and chest pain or angina and mechanism or treatment or management. We included primary reports of clinical and non-clinical data, as well as systematic reviews. Narrative reviews, expert opinions, letters to the editor and other forms of non-primary literature were excluded.

RESULTS

Our search yielded a total of 1595 reports. Of these, 1460 were narrative reviews or irrelevant to the topic and were excluded. A total of 135 reports were used for our review. We used 81 reports for data extraction, which included 13 clinical trials, 4 retrospective reports, 61 case reports, and 3 systematic reviews.

CONCLUSION

We report the incidence and predisposing factors, the value of available diagnostic procedures, and standard medical and invasive treatments. We also speculate on the potential benefit of arginine as a promising option both in prevention as well as treatment of 5-FU-induced chest pain. Finally, gaps of evidence are identified and proposals are made in terms of future research.

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.

Acetylcholine Rechallenge: A First Step Toward Tailored Treatment in Patients With Coronary Artery Spasm

OBJECTIVES

The present study aimed to assess the feasibility and clinical value of acetylcholine (ACh) rechallenge for the detection of coexisting epicardial and microvascular spasm and to determine the efficacy of nitroglycerin in these spasm endotypes.

BACKGROUND

The coexistence of epicardial and microvascular spasm is difficult to identify; thus, its frequency is unknown. Nitroglycerin treatment is equally recommended for both epicardial and microvascular coronary spasm despite contradictory data.

METHODS

In this multicenter study, 95 patients with coronary spasm were included to undergo ACh rechallenge, which consisted of repeated ACh provocation 3 minutes after intracoronary nitroglycerin administration using the same dose that previously induced spasm.

RESULTS

In total, 95 patients (age 61 ± 12 years, 69% female) were included. Fifty-five patients (58%) had microvascular spasm, and 40 patients (42%) had epicardial spasm during initial ACh provocation. In 48% of patients with epicardial spasm, ACh rechallenge revealed coexisting nitroglycerin-persistent microvascular spasm. Nitroglycerin administration before ACh rechallenge prevented reinducibility of epicardial spasm in all patients with focal spasm and in 80% of patients with diffuse spasm. Microvascular spasm was prevented in only 20% by prior nitroglycerin administration but was attenuated in another 49% of patients.

CONCLUSIONS

This study demonstrates a high frequency of epicardial spasm with coexisting nitroglycerin-persistent microvascular spasm. Intracoronary nitroglycerin was very effective in preventing reinducibility of epicardial spasm, whereas it prevented microvascular spasm in only 20% of patients. ACh rechallenge is a novel method that facilitates the detection of coexisting spasm endotypes and may pave the way towards tailored treatment of vasospastic angina.

Favorable Vasomotor Function after Drug-Coated Balloon-Only Angioplasty of De Novo Native Coronary Artery Lesions

Balloon-injured coronary segments are known to harbor abnormal vasomotion. We evaluated whether de novo coronary lesions treated using drug-coated balloon (DCB) are prone to vasospasm and how they respond to ergonovine and nitrate. Among 132 DCB angioplasty recipients followed, 89 patients underwent ergonovine provocation test at 6–9 months follow-up. Within-subject ergonovine- and nitrate-induced diameter changes were compared among three different sites: DCB-treated vs. angiographically normal vs. segment showing prominent vasoreactivity (spastic). No patient experienced clinically refractory vasospastic angina or symptom-driven revascularization during follow-up. Ergonovine induced vasospasm in seven patients; all were multifocal spasm either involving (n = 2) or rather sparing DCB-treated segments (n = 5). None showed focal spasm that exclusively involved DCB-treated lesions. Among 27 patients with vasospastic features, DCB-treated segments showed less vasoconstriction than spastic counterparts (p < 0.001). A total of 110 DCB-treated lesions were analyzed to assess vasomotor function. Vasomotor function, defined as a combined constrictor and dilator response, was comparable between DCB-treated and angiographically normal segments (p = 0.173), while significant differences were observed against spastic counterparts (p < 0.001). In our study, DCB-treated lesions were not particularly vulnerable to vasospasm and were found to have vasomotor function similar to angiographically normal segments, supporting safety of DCB-only strategy in treating de novo native coronary lesions.