Clinical Implications of an Implantable Cardioverter-Defibrillator in Patients With Vasospastic Angina and Lethal Ventricular Arrhythmia

Coronary spasm and vasomotor dysfunction as a cause of MINOCA

Increasing evidence has shown that coronary spasm and vasomotor dysfunction may be the underlying cause in more than half of myocardial infarctions with non-obstructive coronary arteries (MINOCA) as well as an important cause of chronic chest pain in the outpatient setting. We review the contemporary understanding of coronary spasm and related vasomotor dysfunction of the coronary arteries, the pathophysiology and prognosis, and current and emerging approaches to diagnosis and evidence-based treatment.

Vasospastic angina: a review on diagnostic approach and management

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

Case report: Implantable cardioverter-defibrillator implantation with optimal medical treatment for lethal ventricular arrhythmia caused by recurrent coronary artery spasm due to tyrosine kinase inhibitors

Coronary artery spasm (CAS) may induce lethal ventricular arrhythmia due to severe and prolonged vessel constriction. Tyrosine kinase inhibitors are associated with the occurrence of CAS. Optimal medical treatment is the first-line therapeutic option for the management of CAS, whereas patients who experienced aborted sudden cardiac death (SCD) may benefit from implantable cardioverter-defibrillator (ICD) implantation. We report a case of a 63-year-old Chinese man receiving tyrosine kinase inhibitor treatment for liver cancer who presented with recurrent chest discomfort and syncope with an elevation of high-sensitivity troponin T. Emergent coronary angiography showed sub-total occlusion of the left anterior descending artery without other signs of CAS. Percutaneous transluminal coronary angioplasty with a drug-coated balloon was performed successfully with the guidance of intravascular ultrasound. After 5 months, the patient returned to the emergency room for chest discomfort and another episode of syncope. The electrocardiogram showed ST-segment elevation in the inferior and V5–V6 leads compared to the previous event. Coronary angiography was repeated immediately and showed significant luminal stenosis at the midportion of the right coronary artery (RCA), whereas, after administration of intracoronary nitroglycerine, a remarkable recovery of RCA patency was noticed. A diagnosis of CAS was made, and soon after that, the patient rapidly developed ventricular arrhythmia in the coronary care unit. After successful resuscitation, the patient recovered completely and received long-acting calcium channel blockers as well as nitrates therapy. ICD implantation was performed considering the high risk of recurrence of life-threatening ventricular arrhythmia. During the follow-up period, the patient has been free of angina, syncope, or ventricular arrhythmia, and ICD interrogation showed no ventricular tachycardia or ventricular fibrillation. We first reported the case of a patient with CAS induced by regorafenib treatment complicated with severe atherosclerotic coronary disease who survived from sudden cardiac arrest. ICD implantation is indicated in patients who experienced aborted SCD for the prevention of the next lethal ventricular arrhythmia.

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.

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.

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.

Prognostic Significance of Ventricular Arrhythmias in 13 444 Patients With Acute Coronary Syndrome: A Retrospective Cohort Study Based on Routine Clinical Data (NIHR Health Informatics Collaborative VA-ACS Study)

Background A minority of acute coronary syndrome (ACS) cases are associated with ventricular arrhythmias (VA) and/or cardiac arrest (CA). We investigated the effect of VA/CA at the time of ACS on long-term outcomes. Methods and Results We analyzed routine clinical data from 5 National Health Service trusts in the United Kingdom, collected between 2010 and 2017 by the National Institute for Health Research Health Informatics Collaborative. A total of 13 444 patients with ACS, 376 (2.8%) of whom had concurrent VA, survived to hospital discharge and were followed up for a median of 3.42 years. Patients with VA or CA at index presentation had significantly increased risks of subsequent VA during follow-up (VA group: adjusted hazard ratio [HR], 4.15 [95% CI, 2.42-7.09]; CA group: adjusted HR, 2.60 [95% CI, 1.23-5.48]). Patients who suffered a CA in the context of ACS and survived to discharge also had a 36% increase in long-term mortality (adjusted HR, 1.36 [95% CI, 1.04-1.78]), although the concurrent diagnosis of VA alone during ACS did not affect all-cause mortality (adjusted HR, 1.03 [95% CI, 0.80-1.33]). Conclusions Patients who develop VA or CA during ACS who survive to discharge have increased risks of subsequent VA, whereas those who have CA during ACS also have an increase in long-term mortality. These individuals may represent a subgroup at greater risk of subsequent arrhythmic events as a result of intrinsically lower thresholds for developing VA.

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.

Pathophysiology and Diagnosis of Coronary Functional Abnormalities

Approximately one-half of patients undergoing diagnostic coronary angiography for angina have no significant coronary atherosclerotic stenosis. This clinical condition has recently been described as ischaemia with non-obstructive coronary arteries (INOCA). Coronary functional abnormalities are central to the pathogenesis of INOCA, including epicardial coronary spasm and coronary microvascular dysfunction composed of a variable combination of increased vasoconstrictive reactivity and/or reduced vasodilator function. During the last decade - in INOCA patients in particular - evidence for the prognostic impact of coronary functional abnormalities has accumulated and various non-invasive and invasive diagnostic techniques have enabled the evaluation of coronary vasomotor function in a comprehensive manner. In this review, the authors briefly summarise the recent advances in the understanding of pathophysiology and diagnosis of epicardial coronary artery spasm and coronary microvascular dysfunction.

Current Evidence on Long-Term Prognostic Factors in Vasospastic Angina

Vasospastic angina (VSA) is characterized by a reversible spasm of the coronary arteries and is more prevalent in Asians. Vasodilators, such as calcium channel blockers, are effective in relieving coronary spasms and preventing clinical events. Therefore, the prognosis of VSA is generally known to be better than for significant organic stenosis caused by atherosclerosis. However, coronary vasospasm is sometimes associated with fatal complications such as sudden death, ventricular arrhythmia, and myocardial infarction. Thus, it is very important to identify and actively treat high-risk patients to prevent VSA complications. Here, we will review clinical factors associated with long-term prognosis in patients with VSA.

Targeted Temperature Management for In-hospital Cardiac Arrest Caused by Thyroid Storm: A Case Report

Background: Malignant ventricular arrhythmias caused by thyroid storm, such as ventricular tachycardia (VT) or ventricular fibrillation (VF), which are life-threatening, are rare. We report the case of a patient who suffered from cardiac arrest caused by thyroid storm and the rare VF; the patient showed a favorable neurologic outcome after receiving targeted temperature management (TTM) treatment by intravascular cooling measures.

Case presentation: A 24-year-old woman who had lost 20 kg in the preceding 2 months presented to the emergency department with diarrhea, vomiting, fever, and tachycardia. Thyroid function testing showed increased free triiodothyronine (FT3) and free thyroxine (FT4), decreased thyroid-stimulating hormone (TSH), and positive TSH-receptor antibody (TRAB). She was diagnosed with hyperthyroidism and had experienced sudden cardiac arrest (SCA) due to ventricular fibrillation (VF) caused by thyroid storm. The patient was performed with targeted temperature management (TTM) by intravascular cooling measures. Regular follow-up in the endocrinology department showed a good outcome.

Conclusions: Our case not only suggests a new method of cooling treatment for thyroid storm, but also provides evidence for the success of TTM on patients resuscitated from in-hospital cardiac arrest (IHCA) who remain comatose after return of spontaneous circulation (ROSC).

Characteristics and Prognosis of Patients with Vasospastic Angina Diagnosed by a Provocation Test with Secondary Prevention Implantable Cardioverter Defibrillator

This study aimed to evaluate the characteristics and prognosis of patients with vasospastic angina (VSA) diagnosed by a provocation test with a secondary prevention implantable cardioverter defibrillator (ICD), compared with patients with organic coronary stenosis. We retrospectively evaluated 309 consecutive patients who received an ICD implantation between January 2010 and March 2018 in our institutions. Of these patients, 206 were implanted with an ICD for secondary prevention. In these 206 patients, 40 with VSA and 72 with organic coronary stenosis were evaluated. Patients with VSA were characterized by younger age (56.1 ± 13.1 versus 69.2 ± 9.5 years, respectively), and a lower prevalence of diabetes (15.0% versus 40.3%, respectively) and heart failure (2.5% versus 26.4%, respectively) than patients with organic coronary stenosis (P < 0.001). Using the Kaplan-Meier analysis, with the VSA group as the reference, the incidence of appropriate ICD shock was similar between the two groups (hazard ratio, 0.85; 95% confidence interval, 0.341-2.109; P = 0.722). The incidence of ventricular fibrillation was significantly higher in the VSA group (hazard ratio, 0.22; 95% confidence interval, 0.057-0.814; P = 0.024), whereas the incidence of major adverse cardiac events, including cardiac death, nonfatal myocardial infarction, hospitalization for unstable angina pectoris, and heart failure, was significantly higher in the organic coronary stenosis group (hazard ratio, 13.1; 95% confidence interval, 1.756-98.17; P = 0.012). In conclusion, patients with VSA with an ICD implanted for secondary prevention have a higher risk of ventricular fibrillation and lower risk of major adverse cardiac events than patients with organic coronary stenosis.

Severe multivessel coronary artery spasm detected by computed tomography: a case report

Background

Ventricular arrhythmia and sudden cardiac arrest caused by multivessel coronary artery spasm (CAS) is rare. Although coronary angiography (CAG) with provocation testing is the diagnostic gold standard in current vasospastic angina guidelines, it can cause severe procedure-related complications. Here, we report a novel technique involving dual-acquisition coronary computed tomography angiography (CCTA) to detect multivessel CAS in a patient who survived out-of-hospital cardiac arrest (OHCA).

Case summary

A 58-year-old healthy Korean male survived OHCA caused by ventricular fibrillation (VF), experiencing seven episodes of defibrillation and cardiopulmonary resuscitation, and was referred to the Emergency Room. Vital signs were stable and physical examination, electrocardiogram, chest, and brain CT did not show any abnormal findings, except elevated hs-Troponin I levels (0.1146 ng/mL). Echocardiogram revealed a regional wall motion abnormality in the inferior wall, with a low normal left ventricular ejection fraction (50%). A multivessel CAS (both left and right) was detected using a dual-acquisition CCTA technique (presence and absence of intravenous nitrate). During CAG with the 2^nd injection of ergonovine, a prolonged and refractory total occlusion in the proximal-ostial right coronary artery was completely relieved after a seven-cycle intracoronary injection regimen of nitroglycerine. The patient was discharged with the recommendation of smoking and alcohol cessation. Nitrate and calcium channel blockers were also prescribed. The patient had no further events at 3 months of follow-up after discharge.

Discussion

Dual-acquisition CCTA is a promising tool to detect multivessel CAS.

Prognosis of Japanese Patients With Coronary Artery Disease Who Underwent Implantable Cardioverter Defibrillator Implantation - The JID-CAD Study

Background: There has been no large multicenter clinical trial on the prognosis of implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy with a defibrillator (CRT-D) in Japanese patients with coronary artery disease (CAD). The aim of the present study was to compare differences in the prognoses of Japanese patients with CAD between primary and secondary prevention, and to identify potential predictors of prognosis.

Methods and Results: We investigated 392 CAD patients (median age 69 years, 90% male) treated with ICD/CRT-D enrolled in the Japan Implantable Devices in CAD (JID-CAD) Registry. The primary endpoint was all-cause death, and the secondary endpoint was appropriate ICD therapies. Endpoints were assessed by dividing patients into primary prevention (n=165) and secondary prevention (n=227) groups. The mean (±SD) follow-up period was 2.1±0.9 years. The primary endpoint was similar in the 2 groups (P=0.350).

Conclusions: The mortality rate in Japanese patients with CAD who underwent ICD/CRT-D implantation as primary prevention was not lower than that of patients who underwent ICD/CRT-D implantation as secondary prevention, despite the lower cardiac function in the patients undergoing ICD/CRT-D implantation as primary prevention.

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

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

Subcutaneous implantable cardioverter-defibrillator was inappropriate for use in a patient with aborted sudden cardiac death due to coronary spastic angina: a case report

Background

Implantable cardioverter-defibrillator (ICD) is recommended for secondary prevention in patients with coronary spastic angina and aborted sudden cardiac death. The effectiveness of subcutaneous ICD (S-ICD) for patients with coronary artery spastic angina is controversial.

Case summary

A 54-year-old man presented with ventricular fibrillation. Emergent coronary angiography showed diffuse narrowing of the coronary arteries that was reversible with isosorbide dinitrate. He was diagnosed with coronary spastic angina. S-ICD was implanted after the administration of a calcium-channel blocker and nicorandil. Seven months after the implantation, he collapsed again due to sinus node dysfunction and atrioventricular block caused by cardiac ischaemia. He developed cardiac arrest at both admissions. Six hours after the admission, electrocardiogram showed transient right bundle branch block. Inappropriate shocks were delivered because of low R-wave amplitude and T-wave oversense. S-ICD was replaced with a transvenous device in order to manage these two arrhythmias and inappropriate shocks.

Discussion

Patients with coronary artery spasm and aborted sudden cardiac death are candidates for implantation of S-ICD, but there are risks of bradycardia and inappropriate shocks in other ischaemic events.

Early repolarization in the inferolateral leads predicts the presence of vasospastic angina: a novel predictor in patients with resting angina

BACKGROUND

An association between early repolarization and ventricular fibrillation has recently been reported in patients with vasospastic angina (VSA). However, no studies have clarified whether the presence of early repolarization can predict VSA.

METHODS

Participants comprised 286 patients (136 males) with clinically suspected VSA who underwent intracoronary provocation tests using acetylcholine or ergonovine. Patients were divided into a VSA group [n = 94, positive provocation test as induction of coronary arterial spasm (>90% stenosis)] and a non-VSA group (n = 192). Detailed early repolarization data were compared between groups.

RESULTS

The VSA group showed a higher frequency of smokers (28.7%) than the non-VSA group (17.2%; P = 0.02). On baseline 12-lead ECG, early repolarization (defined as a J-point elevation ≥0.1 mV from baseline in both or either of inferolateral leads) was found in 39 patients (inferior leads, n = 27; inferolateral leads, n = 12). Early repolarization was found more frequently in the VSA group (28.7%) than in the non-VSA group (6.2%, P < 0.01). Multivariate analysis revealed early repolarization as an independent predictor of VSA (odds ratio, 5.22; 95% confidence interval, 2.41-11.2; P < 0.01). Early repolarization pattern features including inferior lead, higher amplitude, notched type and horizontal/descending ST segments were associated with increased risk of VSA.

CONCLUSION

In patients with resting chest pain, early repolarization was a predictor of VSA that could be particularly related to the inferior lead, higher amplitude, notched type and horizontal/descending ST segment.

Impact of Myocardial Bridge on Life‐Threatening Ventricular Arrhythmia in Patients With Implantable Cardioverter Defibrillator

Background

Myocardial bridge (MB), common anatomic variant, is generally considered benign, while previous studies have shown associations between MB and various cardiovascular pathologies. This study aimed to investigate for the first time possible impact of MB on long‐term outcomes in patients with implantable cardioverter defibrillator, focusing on life‐threatening ventricular arrhythmia (LTVA).

Methods and Results

This retrospective analysis included 140 patients with implantable cardioverter defibrillator implantation for primary (n=23) or secondary (n=117) prevention of sudden cardiac death. Angiographically apparent MB was identified on coronary angiography as systolic milking appearance with significant arterial compression. The primary end point was the first episode(s) of LTVA defined as appropriate implantable cardioverter defibrillator treatments (antitachyarrhythmia pacing and/or shock) or sudden cardiac death, assessed for a median of 4.5 (2.2–7.1) years. During the follow‐up period, LTVA occurred in 37.9% of patients. Angiographically apparent MB was present in 22.1% of patients; this group showed younger age, lower rates of coronary risk factors and ischemic cardiomyopathy, higher prevalence of vasospastic angina and greater left ventricular ejection fraction compared with those without. Despite its lower risk profiles above, Kaplan–Meier analysis revealed significantly lower event‐free rates in patients with versus without angiographically apparent MB. In multivariate analysis, presence of angiographically apparent MB was independently associated with LTVA (hazard ratio, 4.24; 95% CI, 2.39–7.55; P <0.0001).

Conclusions

Angiographically apparent MB was the independent determinant of LTVA in patients with implantable cardioverter defibrillator. Although further studies will need to confirm our findings, assessment of MB appears to enhance identification of high‐risk patients who may benefit from closer follow‐up and targeted therapies.

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.

Out-of-Hospital Cardiac Arrest due to Coronary Spasm with Recurrent Ventricular Fibrillation

We present a case of ventricular fibrillation (VF) secondary to ischaemia induced by coronary artery spasm. An 82-year-old man initially presented with an out-of-hospital VF arrest. On return of spontaneous circulation (ROSC), he was found to be in fast atrial fibrillation (AF); an invasive coronary angiogram revealed unobstructed coronary arteries. During his hospital stay, he developed chest pain, with concomitant ST elevation on ECG (electrocardiogram), which spontaneously resolved. A repeat coronary angiography revealed coronary spasm. Later, he had further ST elevation resulting in ventricular fibrillation. It became clear his initial presentation was most likely due to coronary vasospasm rather than a plaque-rupture or ventricular scar-related event, and he was thus successfully treated with multiple vasodilators and an implantable cardiac defibrillator. This case report highlights how conventional imaging modalities may not always lead to a diagnosis.

Spasm Provocation Tests under Medication May Help Decide on Medical or Mechanical Therapy in Patients with Aborted Sudden Cardiac Death due to Coronary Spasm

Objective The decision to perform medical or mechanical therapy in patients with aborted sudden cardiac death (ASCD) due to coronary spasm is controversial. The Japanese Circulation Society guidelines for the diagnosis and treatment of patients with coronary spastic angina mentioned that implantable cardioverter-defibrillator (ICD) is one option in patients with ASCD due to coronary spasm. We investigated the usefulness of spasm provocation tests under medications in five patients with ASCD due to coronary spasm. Methods We performed the spasm provocation tests under medications in five ASCD patients due to coronary spasm. Pharmacological spasm provocation tests, including five acetylcholine (ACh) tests, two ergonovine (ER) tests, and two ACh added after ER tests, were performed to estimate the effect of medications to suppressing the next fatal spasms. Results ACh tests under medications did not provoke spasm in one patient but did provoke in two patients. In the remaining two patients, neither the ACh test nor the ER test provoked spasm, but the ACh added after ER test induced a focal spasm in one coronary artery. We increased the medication dosage in four patients. An ICD was implanted in two patients, including one with refractory spasm and one with left main trunk spasm. One patient died due to pulseless electrical activity without ventricular fibrillation, while the remaining four patients survived. Conclusion Spasm provocation tests under medication in patients with ASCD due to coronary spasm may be an option when deciding on medical or mechanical therapy.

Vasospasm-related Sudden Cardiac Death Has Outcomes Comparable with Coronary Stenosis in Out-of-Hospital Cardiac Arrest

BACKGROUND

Characteristics of coronary vasospasm-related sudden cardiac death are not well understood. We aimed to compare the characteristics and clinical outcomes between coronary vasospasm and stenosis, in out-of-hospital cardiac arrest (OHCA) survivors, who underwent coronary angiogram (CAG).

METHODS

We conducted a multicenter retrospective observational registry-based study at 8 Korean tertiary care centers. Data of OHCA survivors undergoing CAG between 2010 and 2015 were extracted. Patients were divided into vasospasm and stenosis (stenosis > 50%) groups based on CAG findings. The primary and the secondary outcomes were survival and a good neurologic outcome at 30 days after OHCA. Patients in the vasospasm and stenosis groups were propensity score matched.

RESULTS

Of the 413 included patients, vasospasm and stenosis groups comprised 87 and 326 patients, respectively. There were 279 (66.7%) survivors and 206 (49.3%) patients with good neurologic outcomes. The vasospasm group had better clinical characteristics for outcome (younger age, less diabetes and hypertension, more prehospital restoration of spontaneous circulation, higher Glasgow Coma Scale, less ST segment elevation, and less requirement of circulatory support). The vasospasm group had better survival (75/87 vs. 204/326, P < 0.001) and good neurologic outcomes (62/87 vs. 144/326, P < 0.001). However, vasospasm was not independently associated with survival (odds ratio [OR], 0.980; 95% confidence interval [CI], 0.400-2.406) or neurologic outcomes (OR, 0.870; 95% CI, 0.359-2.108) after adjustment and vasospasm was not associated with survival and neurologic outcome in propensity score-matched cohorts.

CONCLUSION

Our analysis of propensity score-matched cohorts finds that vasospasm OHCA survivors have survival and neurologic outcomes comparable with those of stenotic OHCA survivors.

Vasospastic Arrest

Vasospastic angina is an uncommon cause of cardiac arrest. We describe a patient who presented with sudden cardiac arrest due to severe coronary vasospasm. Telemetry during the event revealed ventricular arrhythmias and asystole followed by spontaneous self-conversion back to normal sinus rhythm. The patient underwent implantable cardioverter-defibrillator therapy. (Level of Difficulty: Beginner.)

Severe Prinzmetal's Angina Inducing Ventricular Fibrillation Cardiac Arrest

Prinzmetal's angina is a vascular spasm of the coronary artery that can mimic acute coronary syndrome. It is rarely responsible for ventricular arrhythmias and cardiac arrest; however, survivors with these complications are at increased risk for recurrent ventricular arrhythmias and sudden cardiac death. This is true despite the presence of normal cardiac function and optimal medical therapy. Thus, this select population should be considered for an implantable cardioverter defibrillator (ICD). In this case vignette, we describe a healthy 48-year-old female with ventricular fibrillation arrest, followed by recurrent ventricular tachyarrhythmias caused by Prinzmetal's angina.

Ventricular Fibrillation Cardiac Arrest in Young Female from Diffuse Left Anterior Descending Coronary Vasospasm

This is a case of the most severe and potentially fatal complication of coronary artery vasospasm. We report a case of a 40-year-old female presenting to the emergency department (ED) via emergency medical services with chest pain. The patient experienced a ventricular fibrillation cardiac arrest while in the ED. Post-defibrillation electrocardiogram showed changes suggestive of an ST-elevation myocardial infarction (STEMI). Cardiac catheterization showed severe left anterior descending spasm with no evidence of disease. Coronary vasospasm is a consideration in the differential causes of ventricular fibrillation and STEMI seen in the ED.

Unexpected complications of vasospastic coronary artery disease and its successful management

Vasospastic coronary artery disease (CAD) usually occurs during the percutaneous interventions and responds to conventional medical treatment. However, in rare conditions, it may be resistant to medical treatment, resulting in lethal complications, including acute myocardial infarction, ventricular arrhythmia, cardiopulmonary arrest, cardiogenic shock, and acute pulmonary edema. In this case report, a 44-year-old woman was admitted to the hospital with a diagnosis of non-ST-segment elevation myocardial infarction. During a diagnostic coronary angiography and in-hospital stays, multiple catastrophic complications due to vasospastic CAD occurred, and we were able to demonstrate a successful management strategy of these complications.

Long-term prognosis of patients with life-threatening ventricular arrhythmias induced by coronary artery spasm

Aims

Coronary artery spasm (CAS) is associated with ventricular arrhythmias (VA). Much controversy remains regarding the best therapeutic interventions for this specific patient subset. We aimed to evaluate the clinical outcomes of patients with a history of life-threatening VA due to CAS with various medical interventions, as well as the need for ICD placement in the setting of optimal medical therapy.

Methods and results

A multicentre European retrospective survey of patients with VA in the setting of CAS was aggregated and relevant clinical and demographic data was analysed. Forty-nine appropriate patients were identified: 43 (87.8%) presented with VF and 6 (12.2%) with rapid VT. ICD implantation was performed in 44 (89.8%). During follow-up [59 (17-117) months], appropriate ICD shocks were documented in 12. In 8/12 (66.6%) no more ICD therapies were recorded after optimizing calcium channel blocker (CCB) therapy. SCD occurred in one patient without ICD. Treatment with beta-blockers was predictive of appropriate device discharge. Conversely, non-dihydropyridine CCB therapy was significantly protective against VAs.

Conclusion

Patients with life-threatening VAs secondary to CAS are at particularly high-risk for recurrence, especially when insufficient medical therapy is administered. Non-dihydropyridine CCBs are capable of suppressing episodes, whereas beta-blocker treatment is predictive of VAs. Ultimately, in spite of medical intervention, some patients exhibited arrhythmogenic events in the long-term, suggesting that ICD implantation may still be indicated for all.

Myocardial infarction with non-obstructive coronary arteries: a focus on vasospastic angina

Vasospastic angina (VSA) is considered a broad diagnostic category including documented spontaneous episodes of angina pectoris produced by coronary epicardial vasospasm as well as those induced during provocative coronary vasospasm testing and coronary microvascular dysfunction due to microvascular spasm. The hallmark feature of VSA is rest angina, which promptly responds to short-acting nitrates; however, VSA can present with a great variety of symptoms, ranging from stable angina to acute coronary syndrome and even ventricular arrhythmia. VSA is more prevalent in females, who can present with symptoms different from those among male patients. This may lead to an underestimation of cardiac causes of chest-related symptoms in female patients, in particular if the coronary angiogram (CAG) is normal. Evaluation for the diagnosis of VSA includes standard 12-lead ECG during the attack, Holter monitoring, exercise testing, and echocardiography. Patients suspected of having VSA with a normal CAG without a clear myocardial or non-cardiac cause are candidates for provocative coronary vasospasm testing. The gold standard method for provocative coronary vasospasm testing involves the administration of a provocative drug during CAG while monitoring patient symptoms, ECG and documentation of the coronary artery. Treatment of VSA consists of lifestyle adaptations and pharmacotherapy with calcium channel blockers and nitrates.

Ventricular Fibrillation Induced by Coronary Vasospasm in a Patient with Early Repolarization and Hyperthyroidism

Vasospastic angina (VSA) has been recognized as a cause of ventricular fibrillation (VF) degenerating into sudden cardiac death. We experienced a case of VSA with hyperthyroidism in which VF was provoked with an augmented J-wave amplitude in the inferior leads. The patient underwent insertion of an implantable cardioverter-defibrillator for the secondary prevention of VF in addition to taking Ca-channel antagonists. He has shown no recurrence of fatal arrhythmia or anginal attack for a follow-up period of one year.

Cardiogenic Shock due to Pulseless Electrical Activity Arrest Associated with Severe Coronary Artery Spasm

A 75-year-old man was admitted to our hospital for follow-up coronary angiography. Just after starting coronary angiography, his electrocardiogram showed ST-segment elevation in the V1-6, I, II, and aVF leads, and he fell into catastrophic cardiogenic shock. His left coronary arteriogram showed proximal total obstruction in the left anterior descending artery and proximal subtotal occlusion in the left circumflex artery. Because pulseless electrical activity arrest was recognized, cardiopulmonary support was started. After more than 15 minutes' cardiac massage, his blood pressure gradually returned to baseline. During the cardiogenic shock due to pulseless electrical activity arrest, neither ventricular fibrillation nor ventricular tachycardia was recognized.

Subcutaneous implantable cardioverter-defibrillator implantation for ventricular fibrillation caused by coronary artery spasm: a case report

BACKGROUND

Coronary artery spasm usually has a good prognosis, except when it induces lethal ventricular arrhythmias. Implantable cardioverter-defibrillator (ICD) implantation in addition to optimal medical therapy including prescription of coronary vasodilators and smoking cessation is a therapeutic option for coronary artery spasm patients who present with lethal ventricular arrhythmia. Subcutaneous ICDs are now available as an alternative to conventional transvenous ICDs.

CASE SUMMARY

We report the first case of a 50-year-old Japanese male without any structural heart disease who presented with ventricular fibrillation caused by coronary artery spasm, and underwent subcutaneous ICD implantation for secondary prevention of sudden cardiac death (SCD). We attributed his aborted SCD to coronary artery spasm based on findings of cardiac catheterization including acetylcholine provocation test and cardiac electrophysiological study. During the 1 year of follow-up, the patient discharged on calcium channel blockers and nicorandil has been free of angina, ventricular arrhythmias, and appropriate ICD therapy.

DISCUSSION

Coronary artery spasm patients with aborted SCD may be good candidates for implantation of subcutaneous ICDs, because most of them have no need for concomitant bradycardia therapy, cardiac resynchronization therapy, or anti-tachycardia pacing therapy.

Optimal Medications and Appropriate Implantable Cardioverter-defibrillator Shocks in Aborted Sudden Cardiac Death Due to Coronary Spasm

Objective Life-threatening ventricular arrhythmias are recognized in patients with coronary spastic angina. Implantable cardioverter-defibrillators (ICDs) are effective in patients with structural heart disease and ventricular fibrillation. However, the optimal medication for patients with aborted sudden cardiac death (SCD) due to coronary artery spasm after the implantation of ICD remains controversial. Methods We investigated the medications and the numbers of appropriate ICD shocks in 137 patients with a history of aborted SCD due to coronary spasm. Results Appropriate ICD shocks were observed in 24.1% (33/137) of patients with aborted SCD due to coronary spasm during 41 months of follow-up. Only 15 (15.6%) of the 96 patients with ICDs received aggressive medical therapy, including two or three calcium-channel antagonists. The rate of appropriate ICD shocks was significantly higher in Western countries than in Asian countries (42.9% vs. 19.3%, p<0.01), whereas the medications did not differ between the two regions. Appropriate ICD shocks successfully resuscitated 33 patients. Three patients died due to second serious fatal arrhythmias. Conclusion Appropriate ICD shocks were recognized in a quarter of patients with aborted SCD due to coronary spasm and ICD implantation was effective for suppressing the next serious fatal arrhythmia in these patients. We should reconsider prescribing more medications after ICD implantation in patients with aborted SCD due to coronary artery spasm.

Variant Angina and Aborted Sudden Cardiac Death

PURPOSE OF REVIEW

Variant angina, which is characterized by recurrent chest pain and transient ECG changes along with angiographic evidence of coronary artery spasm, generally has a favorable prognosis. However, episodes of ischemia caused by vasospasm may lead to potentially life-threatening ventricular arrhythmias and cardiac arrest, even in patients with no history of prior cardiac disease. This review describes the epidemiology, pathogenesis, clinical spectrum, and management of variant angina, as well as outcomes in patients who present with aborted sudden cardiac death (ASCD).

RECENT FINDINGS

Contrary to prior opinions, evidence from recent observational studies indicate that patients with variant angina presenting with ASCD face a worse prognosis than those without this type of presentation. Predictors of ASCD include age, hypertension, hyperlipidemia, family history of sudden cardiac death, multi-vessel spasm, and left anterior descending artery spasm. Medical therapy alone with calcium channel blockers and nitrates may not be sufficiently protective in these patients and there is lack of concrete data on the optimal management strategy. Current guidelines recommend implantable cardiac defibrillator (ICD) therapy in patients who are survivors of cardiac arrest caused by ventricular fibrillation or unstable ventricular tachycardia after reversible causes are excluded, and should strongly be considered in these patients. Although medical therapy is absolutely imperative for patients with variant angina and a history of ASCD, ICD therapy in these patients is justified. Further large-scale studies are required to determine whether ICD therapy can improve survival in this high-risk group of patients.

Coronary vasospasm-induced polymorphic ventricular tachycardia: a case report and literature review

Introduction

Coronary vasospasm is an uncommon but important cause of myocardial ischaemia and ventricular arrhythmias.

Case presentation

In this report, we present a striking example of vasospasm manifesting as ST-segment elevation and ventricular tachycardia on Holter monitoring. Later, spasm occurred during a procainamide challenge performed for suspected Brugada syndrome. The patient underwent implantable cardioverter-defibrillator insertion and was successfully treated with oral calcium channel blocker.

Discussion

We review contemporary data regarding management and outcomes in coronary vasospasm and discuss the use of implantable defibrillator therapy in patients who have sustained a significant arrhythmic event.

Prinzmetal Angina in a Young Patient with Essential Thrombocythemia, After Anagrelide Initiation - Case Report and Literature Review

We report a case of Prinzmetal angina as inaugural manifestation of coronary disease, in a young adult male patient, recently started on anagrelide for essential thrombocythemia. Moderate proximal left anterior descendent coronary artery stenosis was documented by angiography, and interventional or surgical revascularization has been discussed. Patient’s option was for medical therapy alone. Anagrelide was temporarily withdrawn and rechallenged uneventfully after a couple of months and clinical evolution is good at four years follow-up. The mechanism by which anagrelide could induce coronary spasm and ischemia remains to be clarified.