Overview of the pharmacological spasm provocation test: Comparisons between acetylcholine and ergonovine

Differences in coronary angiographic findings and outcomes between men and postmenopausal women with stable chest pain

BACKGROUND

Despite the significant increase in cardiovascular events in women after menopause, studies comparing postmenopausal women and men are scarce.

METHODS

We analyzed data from a nationwide, multicenter, prospective registry and enrolled 2412 patients with stable chest pain who underwent elective coronary angiography. Binary coronary artery disease (b-CAD) was defined as the ≥50% stenosis of epicardial coronary arteries, including the left main coronary artery.

RESULTS

Compared with the men, postmenopausal women were older (66.6 ± 8.5 vs. 59.5 ± 11.4 years) and had higher high-density lipoprotein cholesterol levels (49.0 ± 12.8 vs. 43.6 ± 11.6 mg/dl, P  < 0.01). The prevalence of diabetes did not differ significantly ( P  = 0.40), and smoking was more common in men than in postmenopausal women ( P  ≤ 0.01). At enrollment, b-CAD and revascularization were more common in men than in postmenopausal women (50.3% vs. 41.0% and 14.4% vs. 9.7%, respectively; both P  < 0.01). However, multivariate analyses revealed that revascularization [odds ratio (OR): 0.72; 95% confidence interval (CI): 0.49-1.08] was not significantly related to sex and a similar result was found in age propensity-matched population (OR: 0.80; 95% CI: 0.52-1.24). During the follow-up period, the secondary composite cardiovascular outcomes were lower in postmenopausal women than in men (OR: 0.55; 95% CI: 0.31-0.98), also consistent with the result using the age propensity-mated population (OR: 0.33; 95% CI: 0.13-0.85).

CONCLUSION

Postmenopausal women experienced coronary revascularization comparable to those in men at enrollment, despite the average age of postmenopausal women was 7 years older than that of men.Postmenopausal women exhibit better clinical outcomes than those of men if optimal treatment is provided.

A Case of Refractory Variant Angina

Coronary vasospasm is defined as the abnormal contraction of an epicardial coronary artery. Variant angina is a severe form of coronary vasospasm, reflecting transmural ischemia with ST-T elevation on an electrocardiogram. A pharmacologic spasm provocation test during coronary angiography is the gold standard evaluation for patients who have not been diagnosed with coronary vasospasm by a non-invasive test. The sensitivity and specificity of pharmacologic spasm provocation testing have been reported to be very high in patients with variant angina. Here, we report the case of a 61-year-old woman who had refractory variant angina. Although a pharmacologic spasm provocation test did not lead to a definitive diagnosis, she had recurrent acute coronary syndrome due to coronary vasospasm. Physicians should be aware of the limitations of the spasm provocation test, even in patients with refractory variant angina.

Innervation of the coronary arteries and its role in controlling microvascular resistance

The coronary circulation plays a crucial role in balancing myocardial perfusion and oxygen demand to prevent myocardial ischemia. Extravascular compressive forces, coronary perfusion pressure, and microvascular resistance are involved to regulate coronary blood flow throughout the cardiac cycle. Autoregulation of the coronary blood flow through dynamic adjustment of microvascular resistance is maintained by complex interactions among mechanical, endothelial, metabolic, neural, and hormonal mechanisms. This review focuses on the neural mechanism. Anatomy and physiology of the coronary arterial innervation have been extensively investigated using animal models. However, findings in the animal heart have limited applicability to the human heart as cardiac innervation is generally highly variable among species. So far, limited data are available on the human coronary artery innervation, rendering multiple questions unresolved. Recently, the clinical entity of ischemia with non-obstructive coronary arteries has been proposed, characterized by microvascular dysfunction involving abnormal vasoconstriction and impaired vasodilation. Thus, measurement of microvascular resistance has become a standard diagnostic for patients without significant stenosis in the epicardial coronary arteries. Neural mechanism is likely to play a pivotal role, supported by the efficacy of cardiac sympathetic denervation to control symptoms in patients with angina. Therefore, understanding the coronary artery innervation and control of microvascular resistance of the human heart is increasingly important for cardiologists for diagnosis and to select appropriate therapeutic options. Advancement in this field can lead to innovations in diagnostic and therapeutic approaches for coronary artery diseases.

Effects of hallucinogenic drugs on the human heart

Hallucinogenic drugs are used because they have effects on the central nervous system. Their hallucinogenic effects probably occur via stimulation of serotonin receptors, namely, 5-HT2A-serotonin receptors in the brain. However, a close study reveals that they also act on the heart, possibly increasing the force of contraction and beating rate and may lead to arrhythmias. Here, we will review the inotropic and chronotropic actions of bufotenin, psilocin, psilocybin, lysergic acid diethylamide (LSD), ergotamine, ergometrine, N,N-dimethyltryptamine, and 5-methoxy-N,N-dimethyltryptamine in the human heart.

What is the meaning of provoked spasm phenotypes by vasoreactivity testing?

Coronary artery epicardial spasm is involved in the pathogenesis of many cardiac disorders. Vasoreactivity testing, such as intracoronary injection of acetylcholine (ACH) or ergonovine (ER), is the gold standard method for the diagnosis of vasospastic angina. Provoked epicardial spasm phenotypes are classified as focal spasm and diffuse spasm. Multiple factors, including sex, ethnicity, and use of coronary vasoactive stimulators, are related to the provoked phenotypes of epicardial spasm. Diffuse-provoked spasm is often observed in females, where focal-provoked spasm is markedly more common in males. ACH provokes more diffuse and distal spasms, whereas ER induces more focal and proximal spasms. Yellow plaque and coronary thrombi are often observed in lesions with focal spasms, and intimal thickness with a sonolucent zone is significantly more common in lesions with focal spasm. Furthermore, clinical outcomes in patients with focal spasm are unsatisfactory compared with those in patients with diffuse spasm. However, the reproducibility and eternality of provoked spasm phenotypes by vasoreactivity testing is uncertain. Coronary atherosclerosis or endothelial damage may affect coronary vasomotor tone. Although coronary artery spasm may persist in the same coronary artery, provoked coronary spasm phenotypes may exhibit a momentary coronary reaction by intracoronary ACH or ER testing.

Insights into the invasive diagnostic challenges of coronary artery vasospasm - A systematic review

Coronary provocation testing is an essential diagnostic procedure when evaluating vasospastic angina. Invasive methods using acetylcholine or ergonovine are considered the current gold standard. Despite efforts from global cardiovascular institutions, current protocols vary in dosage, administration time, and procedural approach. In addition, concerns over the specificity of findings and potential complications have limited routine uptake of this procedure in clinical practice. This systematic review evaluates current diagnostic protocols, focusing on invasive provocation testing. We included studies using intracoronary provocation testing with acetylcholine or ergonovine for the assessment of coronary artery vasospasm that detailed specific elements of the procedure (dosage, administration time, etc.) and included ≥50 patients. A total of 28 articles met strict inclusion criteria. Our review highlights the heterogeneity between current diagnostic protocols for invasive provocation testing. We believe standardization of a diagnostic protocol will encourage both current and future cardiologists to incorporate such procedures in the evaluation of variant angina.

Safety and potential usefulness of sequential intracoronary acetylcholine and ergonovine administration for spasm provocation testing

BACKGROUND

Although guidelines recommend intracoronary acetylcholine (ACh) and ergonovine (ER) provocation testing for diagnosis of vasospastic angina, the feasibility and safety of sequential (combined) use of both pharmacological agents during the same catheterization session remain unclear.

OBJECTIVES

In this study, we investigated the feasibility and safety of sequential intracoronary ACh and ER administration for coronary spasm provocation testing.

METHODS

The study included 235 patients who showed positive results on ACh and ER provocation testing. Initial intracoronary ACh administration was followed by ER administration for left coronary artery (LCA) spasm provocation testing. Subsequently, the right coronary artery (RCA) was subjected to sequential ACh and ER administration for provocation testing. The primary outcome of the study was the safety of sequential intracoronary ACh and ER provocation testing, which was assessed based on a composite of all-cause death, sustained ventricular tachycardia and fibrillation, and cardiogenic shock.

RESULTS

Even in patients with negative results on sequential intracoronary ACh and ER provocation testing in the LCA and only ACh administration into the RCA, additional administration of ER into the RCA showed a positive provocation test result in 33 of 235 (14.0%) patients; three (1.3%) patients developed adverse effects (cardiogenic shock occurred in all cases) during LCA provocation testing. We observed no deaths attributable to spasm provocation testing.

CONCLUSION

Sequential administration of intracoronary ACh and ER was associated with a relatively low major complication rate and may be safe and potentially useful for diagnosis of vasospastic angina.

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

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

Coronary Vascular (DYS) Function and Invasive Physiology Assessment: Insights into Bolus and Continuous Thermodilution Methods

A considerable number of patients with angina or myocardial ischemia have no significant coronary artery disease on invasive angiography. In recent years, several steps towards a better comprehension of the pathophysiology of these conditions, angina or ischemia with non-obstructive coronary arteries (ANOCA/INOCA), have been made. Nevertheless, several gaps in knowledge still remain. This review is intended to provide a comprehensive overview of ANOCA and INOCA, with a particular focus on pathophysiology, recent diagnostic innovations, gaps in knowledge and treatment modalities.

Non-invasive diagnosis of vasospastic angina

Vasospastic angina (VSA), or variant angina, is an under-recognized cause of chest pain and myocardial infarction, especially in Western countries. VSA leads to a declined quality of life and is associated with increased morbidity and mortality. Currently, the diagnosis of VSA relies on invasive testing that requires the direct intracoronary administration of ergonovine or acetylcholine. However, invasive vasoreactivity testing is underutilized. Several non-invasive imaging alternatives have been proposed to screen for VSA. This review aims to discuss the strengths and limitations of available non-invasive imaging tests for vasospastic angina.

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.

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.

A case report: intracoronary acetylcholine testing without a pacemaker may be one option in the left coronary artery

Background

The intracoronary acetylcholine (ACh) and ergonovine (ER) test is employed as a pharmacological spasm provocation test. ACh causes vasoconstriction in patients with coronary endothelial dysfunction such as coronary atherosclerosis, while ER induces coronary vasoconstriction through the activation of coronary smooth muscle.

Case summary

An 84-year-old Japanese man was admitted to our hospital due to resting angina and syncope. Computed tomography coronary angiography (CTCAG) revealed severe proximal left anterior descending (LAD) coronary artery stenosis, but hybrid images of CTCAG and thallium-adenosine myocardial scintigraphy revealed no ischaemia. During syncope, inverted T waves on V5, V6 leads were recognized. After coronary arteriography, mild atherosclerotic stenosis (50%) was found at the proximal LAD artery, and we administered intracoronary ER 104 µg and 80 µg into the left and right coronary arteries because of suspected coronary spasm. However, no provoked spasm was obtained in either vessel. We administered 20, 50, and 100 µg intracoronary ACh into the left coronary artery (LCA) for 30 s without a pacemaker, because neither bradycardia nor cardiac arrest has occurred. Diffuse distal spasm was provoked after the administration of 100 µg ACh and the patient complained of typical chest pain and prodrome before syncope. The patient was diagnosed with coronary spastic angina by the ACh test but not the ER test.

Discussion

Different coronary responses between ACh and ER were observed in this case. Intracoronary ACh testing without a pacemaker may be one option in the LCA if no bradycardia or arrest occurs.

Coronary artery spasm-induced acute myocardial infarction in patients with myocardial infarction with non-obstructive coronary arteries

Coronary artery spasm-induced acute myocardial infarction (CASIAMI) is one of the etiologies of myocardial infarction with non-obstructive coronary arteries (MINOCA). We retrospectively analyzed the incidence and clinical characteristics of Japanese patients with CASIAMI and non-obstructive coronary arteries. We experienced 62 patients with MINOCA (10 thrombosis, 7 unknown causes, and 45 CASIAMI) among 991 patients with suspected AMI. Pharmacological spasm provocation testing was performed in 37 patients. CASIAMI without obstructive coronary arteries was found in 4.5% of patients with suspected AMI and was observed in 73% of patients with MINOCA. Patients with CASIAMI were frequently males and had relatively small AMIs. Spontaneous spasm was recognized in 8 patients. We could reproduce provoked spasm in 37 patients with MINOCA, including 23 patients with multiple spasm. No patients died during the follow-up period. The clinical outcomes in patients with CASIAMI under optimal coronary vasodilators were satisfactory.

What the Cardiologist Needs to Consider in the Management of Oncologic Patients with STEMI-Like Syndrome: A Case Report and Literature Review

In pre-hospital care, an accurate and quick diagnosis of ST-segment elevation myocardial infarction (STEMI) is imperative to promptly kick-off the STEMI network with a direct transfer to the cardiac catheterization laboratory (cath lab) in order to reduce myocardial infarction size and mortality. Aa atherosclerotic plaque rupture is the main mechanism responsible for STEMI. However, in a small percentage of patients, emergency coronarography does not reveal any significant coronary stenosis. The fluoropyrimidine agents such as 5-Fluorouracil (5-FU) and capecitabine, widely used to treat gastrointestinal, breast, head and neck cancers, either as a single agent or in combination with other chemotherapies, can cause potentially lethal cardiac side effects. Here, we present the case of a patient with 5-FU cardiotoxicity resulting in an acute coronary syndrome (ACS) with recurrent episodes of chest pain and ST-segment elevation.. Our case report highlights the importance of widening the knowledge among cardiologists of the side effects of chemotherapeutic drugs, especially considering the rising number of cancer patients around the world and that fluoropyrimidines are the main treatment for many types of cancer, both in adjuvant and advanced settings.

Revisiting the use of the provocative acetylcholine test in patients with chest pain and nonobstructive coronary arteries: A five-year follow-up of the AChPOL registry, with special focus on patients with MINOCA

This study aimed to assess the angiographic characteristics, feasibility and safety of the provocative test with acetylcholine (AChT), and the influence on further treatment and prognosis of Middle European patients in 5-year follow-up, especially focusing on those with a history of myocardial infarction (MI) with nonobstructive coronary arteries (MINOCA). The AChPOL Registry was an ongoing prospective single-center registry that included patients undergoing AChT from December 2010 to March 2013 for further diagnostic evaluation of a suspicious variant angina or coronary microvascular spasm, based on the COVADIS criteria. AChT was injected in incremental doses of 25, 50, and 75µg into the right coronary artery and 25, 50, and 100 µg into the left coronary artery, and the patients were followed up for 5 years. We enrolled 211 patients in the AChPOL Registry. Their mean age was 60.5 ± 7.8 years, with women accounting for 67.8%. The median follow-up was 56 months. AChT revealed variant angina in 99 patients (46.9%) and coronary microvascular spasm in the remaining 72 patients (34.1%). In patients with variant angina, spasm was most frequently observed in the left anterior descending artery (89.9%) and was most frequently diffuse (61.6%). In the microvascular spasm subgroup, there was a significantly higher rate of recurrent chest pain requiring hospitalization in the follow-up than in AChT negative patients. Interestingly, patients with a history of MINOCA had higher rates of MI and recurrent chest pain requiring hospitalization in the follow-up. We showed that AChT was safe in Middle European patients. In the follow-up patients with microvascular spasm and a history of MINOCA had the highest risk of MI and recurrent chest pain requiring hospitalization.

Invasive Diagnosis of Coronary Functional Disorders Causing Angina Pectoris

Coronary vasomotion disorders represent a frequent cause of angina and/or dyspnoea in patients with non-obstructed coronary arteries. The highly sophisticated interplay of vasodilatation and vasoconstriction can be assessed in an interventional diagnostic procedure. Established parameters characterising adequate vasodilatation are coronary blood flow at rest, and, after drug-induced vasodilation, coronary flow reserve, and microvascular resistance (hyperaemic microvascular resistance, index of microcirculatory resistance). An increased vasoconstrictive potential is diagnosed by provocation testing with acetylcholine or ergonovine. This enables a diagnosis of coronary epicardial and/or microvascular spasm. Ischaemia associated with microvascular spasm can be confirmed by ischaemic ECG changes and the measurement of lactate concentrations in the coronary sinus. Although interventional diagnostic procedures are helpful for determining the mechanism of the angina, which may be the key to successful medical treatment, they are still neither widely accepted nor applied in many medical centres. This article summarises currently well-established invasive methods for the diagnosis of coronary functional disorders causing angina pectoris.

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.

Bronchial Asthma and Rest Angina: Is It Safe to Perform Acetylcholine Spasm Provocation Tests in These Patients?

Objective Acetylcholine (ACh) use in patients with bronchial asthma (BA) is contraindicated. We examined the clinical usefulness and safety of ACh spasm provocation tests in rest angina patients with BA. Patients The study subjects were 495 rest angina patients (mean age: 64.4±10.9 years old, male: 81.0%). Organic stenosis was found in 69 patients (13.9%). Methods We investigated 495 rest angina patients who underwent ACh spasm provocation tests. 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. Provoked positive spasm was defined as transient ≥90% luminal narrowing and usual chest pain or ischemic electrocardiogram changes. Results Among 495 rest angina patients, 13 (2.6%) were complicated with BA. Eleven patients with BA were controlled under medications, and two patients had a history of medication for BA. The clinical characteristics were not markedly different between rest angina patients with and without BA. The rate of multi-vessel spasm was markedly higher in patients with BA than that in those without BA. No complications during ACh spasm provocation tests were recognized in rest angina patients with BA, whereas major complications in those without BA were observed in eight patients including two ventricular fibrillations, three non-sustained ventricular tachycardias, and three shocks. We were able to perform all 495 ACh spasm provocation tests without any irreversible complications, while electrical defibrillation was necessary for 2 patients without BA. Conclusion We were able to perform ACh spasm provocation tests in rest angina patients with BA irrespective of the off-label use of ACh.

Coronary provocative tests in the catheterization laboratory: Pathophysiological bases, methodological considerations and clinical implications

The paradigm for the management of patients presenting with angina and/or myocardial ischemia has been historically centered on the detection and treatment of obstructive coronary artery disease (CAD). However, in a considerable proportion (30-50%) of patients undergoing coronary angiography, obstructive CAD is excluded. Thus, functional mechanisms may be involved in determining myocardial ischemia and should be investigated. In particular, coronary vasomotor disorders both at epicardial and at microvascular level may play a crucial role, but a definitive diagnosis of these disorders can at times be difficult, given the transience of symptoms, and often requires the use of coronary provocative tests. Of importance, these tests may provide relevant information on the pathogenic mechanism of myocardial ischemia, allowing physicians to tailor the therapies of their patients. Furthermore, several studies underscored the important prognostic information deriving from the use of coronary provocative tests. Nevertheless, their use in clinical practice is currently limited and mainly restricted to specialized centers, with only a minority of patients receiving a benefit from this diagnostic approach. In this review, we explain the pathophysiological bases for the use of provocative tests, along with their clinical, prognostic and therapeutic implications.

Role of acetylcholine spasm provocation test as a pathophysiological assessment in nonobstructive coronary artery disease

Coronary angiography (CAG) sometimes shows nonobstructive coronary arteries in patients with suspected angina or acute coronary syndrome (ACS). The high prevalence of nonobstructive coronary artery disease (CAD) in those patients has recently been reported not only in Japan but also in Western countries, and is clinically attracting attention. Coronary spasm is considered to be one of the leading causes of both suspected stable angina and ACS with nonobstructive coronary arteries. Coronary spasm could also be associated with left ventricular dysfunction leading to heart failure, which could be improved following the administration of calcium channel blockers. Because we rarely capture spontaneous attacks of coronary spasm with electrocardiograms or Holter recordings, an invasive diagnostic modality, acetylcholine (ACh) provocation test, can be useful in detecting coronary spasm during CAG. Furthermore, we can use the ACh-provocation test to identify high-risk patients with coronary spasm complicated with organic coronary stenosis, and then treat with intensive care. Nonobstructive CAD includes not only epicardial coronary spasm but also microvascular spasm or dysfunction that can be associated with recurrent anginal attacks and poor quality of life. ACh-provocation test could also be helpful for the assessment of microvascular spasm or dysfunction. We hope that cardiologists will increasingly perform ACh-provocation test to assess the pathophysiology of nonobstructive CAD.

Relationship between epicardial adipose tissue volume and coronary artery spasm

BACKGROUND

Epicardial adipose tissue (EAT) is considered to play a critical role in vascular endothelial function. Coronary artery spasm has been postulated to be a causal factor in vascular endothelial abnormalities and atherosclerosis. This study aimed to investigate the relationship between coronary artery spasm and EAT volume, total abdominal adipose tissue (AAT) area, and abdominal visceral adipose tissue (AVAT) area.

METHOD

Among patients undergoing coronary computed tomography (CT) to evaluate coronary artery disease, we identified 110 patients who did not have significant coronary artery stenosis and underwent a coronary spasm provocation test with cardiac catheterization. They were divided into two groups according to the results of the spasm provocation test: spasm-positive and spasm-negative. EAT volume, total AAT area, and AVAT area were evaluated using CT images.

RESULTS

Seventy-seven patients were included in the spasm-positive group and 33 patients in the spasm-negative group. There were no significant differences in baseline clinical characteristics between the two groups, except for the prevalence of current smoking (48% vs. 27%, p = 0.04). EAT volume was significantly higher in the spasm-positive group (108 ± 38 mL vs. 87 ± 34 mL, p = 0.007), while no significant difference was seen in total AAT area (280 ± 113 cm² vs. 254 ± 128 cm², p = 0.32) or AVAT area (112 ± 54 cm² vs. 98 ± 55 cm², p = 0.27). Multivariate logistic analysis indicated that EAT volume (per 10 cm³) (odds ratio, 1.198; 95% confidence interval, 1.035-1.388; p = 0.016) was a significant predictor of coronary artery spasm.

CONCLUSION

Our results suggest that EAT has a strong association with coronary artery spasm, while AAT may not.

Vasospastic angina and overlapping cardiac disorders in patients resuscitated from cardiac arrest

BACKGROUND

Vasospastic angina (VSA) reportedly accounts for one form of sudden cardiac arrest (SCA). Intracoronary acetylcholine (ACh) testing is useful for diagnosing VSA although invasive provocation testing after SCA is a clinical challenge. In addition, even if the ACh test is positive, any causal relationship between VSA and SCA is often unclear because patients with VSA may have other underlying cardiac disorders.

METHODS

A total of 20 patients without overt structural heart disease who had been fully resuscitated from SCA were included. All patients underwent the ACh provocation test and scrutiny such as cardiac computed tomography or magnetic resonance imaging. Patients were followed up for all-cause death or recurrent SCA including appropriate implantable cardioverter defibrillator therapy.

RESULTS

An ACh provocation test was performed 20 ± 17 days after cardiac arrest. Fifteen out of 20 (75.0%) patients had a positive ACh test and 2 (10.0%) had adverse events such as ventricular tachycardia and transient cardiogenic shock during the test. In patients with a positive ACh test, 6 of 15 (40.0%) patients had other overlapping cardiac disorders such as long QT syndrome, Brugada syndrome, cardiac sarcoidosis, myocarditis, or cardiomyopathy. Long-term prognosis was not different regardless of a positive ACh test or the presence of other cardiac disorders overlapping with VSA.

CONCLUSIONS

Three-quarters of the patients who had been resuscitated from SCA had a positive ACh test. Further examinations revealed other overlapping cardiac disorders in addition to VSA in 40% of patients with a positive ACh test.

Pharmacological spasm provocation testing in 2500 patients: provoked spasm incidence, complications and cardiac events

Pharmacological spasm provocation tests such as acetylcholine (ACh) and ergonovine (ER) had been performed in the clinic. We retrospectively analyzed the incidence of provoked spasm, complications during testing and the cardiac events after these tests. From January 1991 and October 2018, we performed pharmacological spasm provocation tests in 2500 patients: 1810 ACh tests, 1232 ER tests, 542 both tests, and 310 ACh added after ER tests. ACh was injected in incremental doses of 20/50/100/200 μg into the LCA and 20/50/80 μg into the RCA. ER was administered as a total dose of 64 μg into the LCA and 40 μg into the RCA. When adding ACh after ER, the total dose was 50/80 μg into the RCA and 100/200 μg into the LCA. Positive spasm was defined as ≥ 90% stenosis and usual chest pain or ischemic ECG changes. Mean follow-up duration was 47.5 ± 29.9 months. Overall, provoked positive spasm was found in 1095 patients (43.8%). The incidence of positive provoked spasm during ACh testing was significantly higher than that during other tests (ACh: 48.7% vs. ER: 28.9%, Both: 24%, ACh added after ER: 33.5%, p < 0.001). Multiple spasms were remarkably more frequent during ACh testing compared with the other 3 types of testing (ACh: 28.2% vs. ER: 7.4%, Both: 4.1%, ACh added after ER: 13.2%, p < 0.001). No death or acute myocardial infarction was observed, while major complications during ACh testing were significantly more frequent than during ER testing. Readmission due to recurrent angina pectoris in spasm-positive patients was remarkably more frequent than in spasm-negative patients. The incidence of sudden cardiac death, ventricular fibrillation, and acute coronary syndrome were not different between the spasm-positive and spasm-negative groups during the follow-up periods. We could perform all spasm provocation tests without any irreversible complications. All sequential spasm provocation tests were useful for documenting coronary spasm.

The Significance of Recognizing Myocardial Bridge in the Coronary Spasm Diagnosis in Myocardial Infarction with Nonobstructive Coronary Arteries

A 61-year-old man experienced chest oppression for 1 hour. He was positive for troponin T and underwent emergent coronary angiography (CAG), which did not reveal significant coronary stenosis. He was diagnosed with myocardial infarction with nonobstructive coronary arteries (MINOCA). We performed a spasm-provocation test, which revealed a focal spasm at the segment of the myocardial bridge. After receiving a calcium-channel blocker, he exhibited a good clinical course. Coronary spasm is considered an underlying cause of MINOCA; therefore, the presence of a myocardial bridge may help with the diagnosis.

Transitional changes of acetylcholine spasm provocation test procedures

Intracoronary acetylcholine (ACh) testing has become popular in the world as a spasm provocation test as well as an ergonovine test. Intracoronary ACh test based on the Japanese Circulation Society guidelines is necessary to insert a temporary pace maker (PM). We analyzed the ACh spasm provocation test procedures retrospectively. We performed 1829 ACh spasm provocation testing during 28 years. We investigated the procedural approach sites of artery and vein. Femoral artery and vein approach, brachial artery and femoral vein approach, brachial artery and vein approach, radial artery and brachial vein approach, radial artery and femoral vein approach were performed in 292 patients (16.0%), 498 patients (27.2%), 589 patients (32.2%), 252 patients (13.8%), and 175 patients (9.6%), respectively. We could perform the ACh testing by the femoral artery and brachial artery in all patients, while the success rate of radial artery approach was 97.1%. We could also insert the temporary PM by the brachial vein in 94.8% (841/887) of the study patients, whereas we could insert the temporary PM in all femoral vein approach [100% (965/965)]. We experienced the pulmonary embolism by the femoral artery and vein approach in two patients, while we also had the arterio-venous fistula necessary for surgical repair in two patients by the brachial artery and vein approach. Although there was no difference about the procedure-related major complications among the various procedures, we had no pulmonary embolism or arterio-venous fistula by the radial artery and brachial vein approach. Considering the disinfection with povidone iodine, procedural performance or procedure-related complications by the ACh testing, we recommend that radial artery and brachial vein approach is more comfortable method of the future ACh testing not only for patients but also for operators.

Vasospastic Angina Diagnosed by the Spasm Provocation Test with the Combined Use of the Acetylcholine and Ergonovine Provocation Tests

The spasm provocation test (SPT) is important for diagnosing vasospastic angina (VSA), and acetylcholine (ACh) is usually used for this test in Japan. However, some patients with VSA have negative SPT results with the use of the standard ACh regimen alone. We herein report two cases in which VSA was diagnosed by the SPT with the combined use of ACh and ergonovine (EM). VSA could not be diagnosed in either case by the SPT using ACh infusions alone. For patients with negative SPT results, cardiologists should consider performing the SPT using a combination of ACh and EM.

The functional assessment of patients with non-obstructive coronary artery disease: expert review from an international microcirculation working group

Symptomatic non-obstructive coronary artery disease (NOCAD) is an increasingly recognised entity that is associated with poor cardiovascular outcomes. Nearly half of those undergoing coronary angiography for appropriate indications, such as typical angina, or a positive stress test have no obstructive lesion. There are no guideline recommendations as to how to care properly for these patients. Physiologic assessment of the coronary arteries beyond two-dimensional angiography is not standardised, yet it can provide valuable information in patients presenting with typical angina in the setting of NOCAD. In this consensus document, we detail steps for the interventional cardiologist to evaluate the patient with symptomatic NOCAD in the cardiac catheterisation laboratory, first with the assessment of coronary flow reserve (CFR), and then with delineation of deficiencies in non-endothelium-dependent CFR (CFRne) versus endothelium-dependent CFR (CFRe) using provocative agents such as adenosine and acetylcholine, respectively, followed by the evaluation of smooth muscle function with nitroglycerine (NTG). Once the mechanism behind the anginal symptoms is established, one can identify the appropriate treatment strategies to address the physiologic deficiency that is present. Despite an established safety profile, a comprehensive assessment may be considered for selected patients which requires an understanding of the appropriate invasive evaluation by the practising interventional cardiologist when evaluating not only patients with obstructive CAD but also those with NOCAD.

Acetylcholine spasm provocation test by trans-radial artery and brachial vein approach

BACKGROUND

Temporary pace maker is necessary because of transient block or bradycardia during the intracoronary acetylcholine spasm provocation tests based on the Japanese Circulation Society guidelines.

OBJECTIVES

We examined the feasibility and safety of the acetylcholine spasm provocation test via the radial artery and brachial vein approach.

METHODS

We tried to perform the acetylcholine spasm provocation tests in 252 patients via the radial artery and brachial vein approach procedures during 5 years. Acetylcholine was injected in incremental doses of 20/50/80 μg into the right coronary artery (RCA) and 20/50/100/200 μg into the left coronary artery (LCA). Back-up pacing rate was set at 40 beats/min. Positive spasm was defined as transient ≥90% luminal narrowing and ischemic electrocardiographic change or usual chest pain.

RESULTS

The procedure success of radial artery and brachial vein access was 94.4% (238/252) and 93.3% (235/252), respectively. We performed 221 patients (87.7%) with acetylcholine tests by radial artery and brachial vein approach. We changed to the brachial approach due to the failures of radial artery access in 14 patients. We also changed to the femoral vein in 11 patients and internal jugular vein in two patients. Back-up pace maker rhythm was observed in 92.1% (232/252) of all study patients, while it was significantly higher in the RCA testing than that in the LCA tests (84.9% (191/225) vs. 52.2% (131/251), P < 0.001). No irreversible complication was found.

CONCLUSIONS

We recommend the radial artery and brachial vein approach for safety and convenience when performing the acetylcholine spasm provocation tests.

Dose maximal acetylcholine dose into the left coronary artery affect the positive provoked spasm in the left circumflex artery?

BACKGROUND

Positive provoked spasm in the left circumflex artery (LCX) is lower than that in the left anterior descending artery and right coronary artery (RCA).

PATIENTS AND METHODS

We examined the provoked positive spasm in the LCX between the maximal acetylcholine (ACh) 100 μg period (January 1991 to July 2012, 1474 patients: the former period) and the maximal ACh 200 μg period (August 2012 to August 2018, 336 patients: the latter period). ACh was injected in incremental dose of 20/50/100/200 μg into the left coronary artery and of 20/50/80 μg into the RCA. Positive spasm was defined as at least 90% stenosis and usual chest symptoms or ischemic ECG changes.

RESULTS

Provoked positive spasm in the latter period was significantly higher than that in the former period (65.5 vs. 39.1%, P < 0.001). The positive spasm increase of RCA and left anterior descending artery was 143 and 159%, whereas the increase of LCX was 204%. Multiple-vessel spasm was also increased in the latter period.

CONCLUSION

Maximal ACh dose into the left coronary artery may affect the positive spasm in the LCX and multiplevessel spasm.

Catheter-induced Spasm in the Proximal Right Coronary Artery

Objectives The clinical characteristics in patients with catheter-induced spasm in the proximal right coronary artery (RCA) are controversial. We performed a clinical analysis of catheter-induced spasm in the RCA. Methods We retrospectively analyzed 5,296 consecutive patients who underwent diagnostic or follow-up angiography during a 26-year period. During this period, we found 40 patients with catheter-induced spasm in the RCA. We compared the clinical characteristics and procedures of cardiac catheterization in patients with catheter-induced spasm in the RCA with those in patients without such spasm. Results The frequency of catheter-induced spasm in the RCA was 0.75% (40/5,296). We performed pharmacological spasm provocation tests in 36 of 40 patients after spasm relief. Positive spasm was observed in 32 patients (88.9%), and 25 patients (78.1%) had multiple spasms. The catheter procedures, including the approach sites (radial/brachial/femoral), catheter size (4/5/6Fr) and catheter type (Judkins right/Sones/Shared/Judkins left 3.5/Amplatz) were not markedly different between the two groups. A multivariate analysis showed that positive spasm [odds ratio (OR): 7.030, 95% confidence interval (CI): 1.920-25.700], a younger age (OR: 0.937, 95% CI: 0.910-0.965) and diabetes mellitus (OR: 0.278, 95% CI: 0.083-0.928) were the determinant factors for the catheter-induced spasm. Conclusion Approximately 80% of patients with catheter-induced spasm in the proximal RCA had coronary spastic angina. Positive provoked spasm was the most powerful determinant factor for catheter-induced spasm.

Coronary spasm: It’s common, but it’s still unsolved

Coronary spasm is caused by a transient coronary narrowing due to the constriction of epicardial coronary artery, which leads to myocardial ischemia. More than 50 years have passed since the first recognition of coronary spasm, and many findings on coronary spasm have been reported. Coronary spasm has been considered as having pivotal roles in the cause of not only rest angina but also exertional angina, acute coronary syndrome, and heart failure. In addition, several new findings of the mechanism of coronary spasm have emerged recently. The diagnosis based mainly on coronary angiography and spasm provocation test and the mainstream treatment with a focus on a calcium-channel blocker have been established. At a glance, coronary spasm or vasospastic angina (VSA) has become a common disease. On the contrary, there are several uncertain or unsolved problems regarding coronary spasm, including the presence of medically refractory coronary spasm (intractable VSA), or an appropriate use of implantable cardioverter defibrillator in patients with cardiac arrest who have been confirmed as having coronary spasm. This editorial focused on coronary spasm, including recent topics and unsolved problems.

Differential incidence and morphology of provoked spasm between intracoronary acetylcholine and ergonovine testing: recommendation of supplementary use

When cardiologists diagnose patients with coronary spastic angina, Japanese Circulation Society (JCS) guidelines recommend the intracoronary injection of acetylcholine (ACh) and ergonovine (ER) as class I. However, the pharmacological difference between ACh and ER is controversial in the clinic. We performed both ACh and ER tests in the same 528 patients during 26 years. We investigated the provoked spasm configuration, spasm site, and clinical characteristics of provoked spasm between ACh and ER, retrospectively. We defined positive spasm as ≥90% luminal narrowing. Provoked positive spasm was observed in 161 right coronary arteries (RCA) including 83 ACh just positive, 35 ER just positive, and 43 both positive. In contrast, positive spasm was documented in 172 left coronary arteries (LCA) including 94 ACh just positive, 28 ER just positive, and 50 both positive. ACh provoked spasm more distally and diffusely, while ER induced spasm more proximally and totally or focally in the RCA. In the LCA, ACh provoked spasm more proximally, whereas ER induced spasm more distally. ER testing after the negative ACh tests of RCA and LCA documented new positive spasms in 10.3% (35/340) and 7.4% (28/376), respectively. Coronary artery trees may each have a sensitive receptor on each segment. We recommend the supplementary use of ACh and ER to document coronary artery spasm in the cardiac catheterization laboratory.

Increased frequency of angina attacks caused by switching a brand-name vasodilator to a generic vasodilator in patients with vasospastic angina: Two case reports

It is well known that calcium channel blockers (CCBs) are the first line of therapy for vasospastic angina (VSA). Here, we report two cases of VSA with an increase in the frequency of angina attacks after switching from a brand-name to a generic CCB. In both cases, angina recurred upon switching from a brand-name CCB to a generic CCB during follow-up. The patients’ condition improved upon switching back to the original CCB. Both cases involved a high severity of VSA, based on the results of spasm provocation testing. These findings suggest that, in some patients with severe VSA, the frequency of angina attacks increases when switching from a brand-name CCB to a generic CCB. Cardiologists should consider this factor when prescribing drugs for angina.

Relationships between more than 90% coronary luminal narrowing induced by ergonovine provocation test and ECG ischemic change as well as chest symptoms

In the clinic, patients with ≥90% luminal narrowing during ergonovine (ER) testing had variable response. We investigated ischemic findings and chest symptoms in patients with ≥90% luminal narrowing when performing ER tests, retrospectively. We performed 1210 ER tests over 26 years (1991-2016). We analyzed chest symptoms and positive ischemic ECG changes during ER tests. More than 90% luminal narrowing was found in 352 patients (29.1%) including 211 patients in the right coronary artery (RCA) and 217 patients in the left coronary artery (LCA). Chest symptom was observed in 290 patients (82.4%) including 162 patients in the RCA and 179 patients in the LCA. ST elevation was found in 154 patients including 98 in the RCA and 73 patients in the LCA, while ST depression was recognized in 81 patients including 38 patients in the RCA and 62 patients in the LCA. Two-third of patients with ≥90% luminal narrowing had significant ischemic ECG changes, whereas 60.5% of patients with ≥90% luminal narrowing complained usual chest pain accompanied with significant ischemic ECG changes. Unusual chest symptom was complained in 7.1% of patients with ≥90% luminal narrowing. Neither chest symptom nor ECG changes was found in 48 patients (13.6%) with ≥90% luminal narrowing. We should understand some limitation to diagnose positive coronary spasm during ER tests.