Clinical characteristics and long-term prognosis of vasospastic angina patients who survived out-of-hospital cardiac arrest: multicenter registry study of the Japanese Coronary Spasm Association

Clinical features and prognosis of type 2 myocardial infarction in vasospastic angina

BACKGROUND

Although generally the prognosis of vasospastic angina is considered excellent, vasospasm has been shown to be a cause of type 2 myocardial infarction. This study was performed to investigate the clinical characteristics and prognosis of patients with vasospastic angina complicated with type 2 myocardial infarction.

METHODS

We performed a retrospective analysis of 171 consecutive patients with definite vasospastic angina (median age, 64 years; 55.0% were male) who visited the Kameda Medical Center with chest pain and in whom cardiac troponin I level was measured between 2005 and 2013. The patients were divided into type 2 myocardial infarction and non-type 2 myocardial infarction groups. A diagnosis of type 2 myocardial infarction was based on a serum cardiac troponin I value >99th percentile upper reference limit. The primary end point was a combination of nonfatal myocardial infarction or death by any cause.

RESULTS

A total of 42 patients (24.6%) were diagnosed with type 2 myocardial infarction, and the type 2 myocardial infarction group had a higher incidence of combined end point than the non-type 2 myocardial infarction group during the median follow-up of 4.4 years (26.2% vs 9.3%, respectively, P = .008). Type 2 myocardial infarction remained an independent predictor of combined end point even after adjusting by the Japanese Coronary Spasm Association risk factors for combined end point (hazard ratio, 2.84; 95% confidence interval, 1.22-6.61; P = .02).

CONCLUSIONS

Approximately one quarter of patients with vasospastic angina were associated with type 2 myocardial infarction, and this population should be identified as a new high-risk subgroup of those with vasospastic angina requiring an alternative treatment strategy.

Life-threatening ventricular arrhythmia due to silent coronary artery spasm: usefulness of I-123 metaiodobenzylguanidine scintigraphy for detecting coronary artery spasm in the era of automated external defibrillators: a case report

Introduction

Cardiac arrhythmia is sometimes life-threatening, and automated external defibrillators are presently used in some countries. Coronary artery spasm is one of the primary causes of life-threatening arrhythmia. In general, chest symptoms are key indicators of possible coronary artery spasm; however, if chest symptoms are not present, clinicians may not suspect this disease. We encountered a patient who had recovered from ventricular fibrillation treated by using an automated external defibrillator, and silent coronary artery spasm was considered to be the cause of this life-threatening arrhythmia. In this case, I-123 metaiodobenzylguanidine scintigraphy was a useful screening tool for a silent coronary artery spasm.

Case presentation

A 72-year-old Japanese man was transferred to our hospital after recovering from ventricular fibrillation treated by using an automated external defibrillator. He had never complained of chest symptoms previously. Decreased uptake of I-123 metaiodobenzylguanidine was observed in the inferolateral and anteroseptal walls of the left ventricle. A spasm provocation test of the coronary artery was performed, and silent coronary artery spasm was diagnosed as the underlying disease.

Conclusion

Non-invasive I-123 metaiodobenzylguanidine scintigraphy was a useful screening tool for silent coronary artery spasm as a possible cause of cardiopulmonary arrest in a patient with no chest symptoms.

Some observations on and controversies about coronary arterial spasm

The pathogenesis, clinical features, diagnosis, and treatment of spasm of epicardial coronary arteries are reviewed briefly, especially with regard to some issues that remain controversial. For diagnosis, emphasis is placed on the need for objective observations during an attack, even if that requires an attempt at pharmacologic provocation during coronary arteriography, or during echocardiography when prior arteriography has demonstrated the absence of severe coronary stenosis.

Safety and optimal protocol of provocation test for diagnosis of multivessel coronary spasm

We examined the safety of acetylcholine (ACh) and ergonovine (ER) tests retrospectively and investigated the optimal protocol of provocation test for diagnosis of multivessel coronary spasm. We performed 1546 ACh tests and 1114 ER tests during 23 years. ACh was injected in incremental doses of 20/50/80 μg into the right coronary artery (RCA) and of 20/50/100/200 μg into the left coronary artery (LCA) over 20 s. ER was administered in total doses of 40 μg into the RCA and of 64 μg into the LCA over 2-4 min. When a coronary spasm was induced and did not resolve spontaneously within 3 min after the completion of ACh/ER injection, or when hemodynamic instability due to coronary spasms occurred, 2.5-5.0 mg of nitrate was administered into the responsible vessel. To relive provoked spasm, it is necessary to administer nitrate in 31 cases by ACh and in 76 cases by ER (2.0 vs. 6.8 %, p < 0.01) before another vessel attempts. Multivessel spasms were often observed in LCA testing than in RCA testing on both agents [ACh: 78.6 % (11/14) vs. 11.8 % (2/17), p < 0.001, ER: 37.8 % (14/37) vs. 20.5 % (8/39), ns]. Even after the administration of nitrates, positive coronary spasm was obtained in 21.1 % by ACh and 52.9 % by ER tests on another coronary artery. No irreversible complications were recognized on both tests. We should firstly perform spasm provocation tests in the LCA and we may be able to diagnose another vessel spasm by performing the complete spasm provocation tests after the administration of nitrates to relieve provoked spasm in the first attempt.

2014 Williams Harvey Lecture: importance of coronary vasomotion abnormalities-from bench to bedside

Coronary vasomotion abnormalities play important roles in the pathogenesis of ischaemic heart disease, in which endothelial dysfunction and coronary artery spasm are substantially involved. Endothelial vasodilator functions are heterogeneous depending on the vessel size, with relatively greater role of nitric oxide (NO) in conduit arteries and predominant role of endothelium-derived hyperpolarizing factor (EDHF) in resistance arteries, where endothelium-derived hydrogen peroxide serves as an important EDHF. The functions of NO synthases in the endothelium are also heterogeneous with multiple mechanisms involved, accounting for the diverse functions of the endothelium in vasomotor as well as metabolic modulations. Cardiovascular abnormalities and metabolic phenotypes become evident when all three NO synthases are deleted, suggesting the importance of both NO and EDHF. Coronary artery spasm plays important roles in the pathogenesis of a wide range of ischaemic heart disease. The central mechanism of the spasm is hypercontraction of vascular smooth muscle cells (VSMCs), but not endothelial dysfunction, where activation of Rho-kinase, a molecular switch of VSMC contraction, plays a major role through inhibition of myosin light-chain phosphatase. The Rho-kinase pathway is also involved in the pathogenesis of a wide range of cardiovascular diseases and new Rho-kinase inhibitors are under development for various indications. The registry study by the Japanese Coronary Spasm Association has demonstrated many important aspects of vasospastic angina. The ongoing international registry study of vasospastic angina in six nations should elucidate the unknown aspects of the disorder. Coronary vasomotion abnormalities appear to be an important therapeutic target in cardiovascular medicine.

ST-elevation myocardial infarction secondary to coronary artery spasm provoked by food

We describe a patient with recurrent episodes of inferior ST elevation, secondary to coronary artery spasm. Each episode appeared to be provoked by the ingestion of rice and accompanied by a troponin T rise. An inpatient coronary angiogram immediately following an episode of pain demonstrated a focal area of spasm affecting the right coronary artery, which resolved with intracoronary nitrate injection. Although these episodes were self-limiting, cardiac MRI confirmed an acute subendocardial infarct. An association between food substances and coronary artery spasm with subsequent infarction has not been documented previously. Following appropriate advice and titration of antispasmodic medication, the patient has been pain free.

Clinical features and prognosis of patients with coronary spasm-induced non-ST-segment elevation acute coronary syndrome

BACKGROUND

The prevalence, clinical features, and long-term outcome of patients with non-ST-segment elevation acute coronary syndrome (NSTE ACS) associated with coronary spasm are not fully investigated.

METHODS AND RESULTS

This observational multicenter study enrolled 1601 consecutive patients with suspected NSTE-ACS who underwent cardiac catheterization between January 2001 and December 2010. A culprit lesion was found in 1152 (72%) patients. In patients without a culprit lesion, the acetylcholine provocation test was performed in 221 patients and was positive in 175 patients. In the other patients, coronary spasm was verified in 145 patients during spontaneous attack. Spasm-induced NSTE-ACS was diagnosed in 320 (20%) patients. Multivariable analysis identified age <70 years (odds ratio [OR] 2.19, 95% CI 1.58 to 3.04), estimated glomerular filtration rate >60 mL/min per 1.73 m(2) (OR 1.72, 95% CI 1.16 to 2.56), and lack of hypertension (OR 2.55, 95% CI 1.90 to 3.41), dyslipidemia (OR 2.76, 95% CI 2.05 to 3.73), diabetes mellitus (OR 2.49, 95% CI 1.78 to 3.48), previous myocardial infarction (OR 5.37, 95% CI 2.89 to 10.0), and elevated cardiac biomarkers (OR 2.84, 95% CI 2.11 to 3.83) as significant correlates of spasm-induced NSTE-ACS (P<0.01 for all variables). Transient ST-segment elevation during spontaneous attack (variant angina) was observed in 119 patients with spasm-induced NSTE-ACS. Variant angina was more common in nondyslipidemic men among patients with spasm-induced NSTE-ACS.

CONCLUSIONS

The study showed frequent involvement of coronary spasm in the pathogenesis of NSTE-ACS. Variant angina was observed in one third of patients with spasm-induced NSTE-ACS. Coronary spasm should be considered even in patients with less coronary risk factors and nonobstructive coronary arteries.

Prognostic stratification of patients with vasospastic angina: a comprehensive clinical risk score developed by the Japanese Coronary Spasm Association

OBJECTIVES

The present study aimed to develop a comprehensive clinical risk score for vasospastic angina (VSA) patients.

BACKGROUND

Previous studies demonstrated various prognostic factors of future adverse events in VSA patients. However, to apply these prognostic factors in clinical practice, the assessment of their accumulation in individual patients is important.

METHODS

The patient database of the multicenter registry study by the Japanese Coronary Spasm Association (JCSA) (n = 1,429; median 66 years; median follow-up 32 months) was utilized for score derivation.

RESULTS

Multivariable Cox proportional hazard model selected 7 predictors of major adverse cardiac events (MACE). The integer score was assigned to each predictors proportional to their respective adjusted hazard ratio; history of out-of-hospital cardiac arrest (4 points), smoking, angina at rest alone, organic coronary stenosis, multivessel spasm (2 points each), ST-segment elevation during angina, and beta-blocker use (1 point each). According to the total score in individual patients, 3 risk strata were defined; low (score 0 to 2, n = 598), intermediate (score 3 to 5, n = 639) and high (score 6 or more, n = 192). The incidences of MACE in the low-, intermediate-, and high-risk patients were 2.5%, 7.0%, and 13.0%, respectively (p < 0.001). The Cox model for MACE between the 3 risk strata also showed prognostic utility of the scoring system in various clinical subgroups. The average prediction rate of the scoring system in the internal training and validation sets were 86.6% and 86.5%, respectively.

CONCLUSIONS

We developed a novel scoring system, the JCSA risk score, which may provide the comprehensive risk assessment and prognostic stratification for VSA patients.

Favorable outcomes of patients with vasospastic angina associated with cardiac arrest

BACKGROUND

The long-term survival of vasospastic angina (VSA) patients is generally good, so long as they remain on calcium channel blockers (CCBs) and avoid smoking. However, the pathogenesis, appropriate treatments, and prognosis of VSA associated with cardiac arrest remain unclear. This study aimed to elucidate the clinical features and long-term outcomes of patients with VSA associated with cardiac arrest.

METHODS AND RESULTS

Eighteen consecutive patients with VSA associated with cardiac arrest [13 patients resuscitated after out-of-hospital cardiac arrest (OHCA) and 5 resuscitated after in-hospital-cardiac arrest] were retrospectively analyzed. Sixteen of the eighteen patients were smokers. None had other cardiac diseases possibly causing cardiac arrest. Although 1 patient resuscitated after OHCA later died of cerebral hypoxia, the remaining 17 were discharged without complications. One patient died of cancer 50 months after resuscitation. The other 16 patients are still alive and none have shown ventricular arrhythmias, syncope, or cardiac arrest during a mean follow-up of 67 months. All are treated with long-acting CCBs/nitrates and successfully quit smoking. Six patients received implantable cardioverter defibrillators (ICD). However, none demonstrated any ventricular arrhythmias and appropriate ICD actuation was achieved.

CONCLUSION

Appropriate medical treatment can achieve favorable long-term outcomes even for patients with VSA associated with cardiac arrest.

Coronary vasomotor response to intracoronary acetylcholine injection, clinical features, and long-term prognosis in 873 consecutive patients with coronary spasm: analysis of a single-center study over 20 years

BACKGROUND

The aim of this study was to elucidate the correlation between angiographic coronary vasomotor responses to intracoronary acetylcholine (ACh) injection, clinical features, and long-term prognosis in patients with vasospastic angina (VSA).

METHODS AND RESULTS

This is a retrospective, observational, single-center study of 1877 consecutive patients who underwent ACh-provocation test between January 1991 and December 2010. ACh-provoked coronary spasm was observed in 873 of 1637 patients included in the present analysis. ACh-positive patients were more likely to be older male smokers with dyslipidemia, to have a family history of ischemic heart disease, and to have a comorbidity of coronary epicardial stenosis than were ACh-negative patients. ACh-positive patients were divided into 2 groups: those with focal (total or subtotal obstruction, n=511) and those with diffuse (severe diffuse vasoconstriction, n=362) spasm patterns. Multivariable logistic regression analysis identified female sex and low comorbidity of coronary epicardial stenosis to correlate with the ACh-provoked diffuse spasm pattern in patients with VSA. Kaplan-Meier survival curve indicated better 5-year survival rates free from major adverse cardiovascular events in patients with diffuse spasm pattern compared with those with focal spasm pattern (P=0.019). Multivariable Cox hazard regression analysis identified diffuse spasm pattern as a negative predictor of major adverse cardiovascular events in patients with VSA.

CONCLUSIONS

ACh-induced diffuse coronary spasm was frequently observed in female VSA patients free of severe coronary epicardial stenosis and was associated with better prognosis than focal spasm. These results suggest the need to identify the ACh-provoked coronary spasm subtypes in patients with VSA.

Recurrent ventricular fibrillation under sufficient medical treatment in patient with coronary artery spasm

In cases of coronary artery spasm, life-threatening ventricular arrhythmias are possible and can lead to sudden cardiac death. Treatment for this condition includes implantable cardioverter defibrillators, but their effectiveness in patients who present with ventricular fibrillation is debated. Our patient presented with intractable ventricular fibrillation episodes that triggered shocks from her implanted defibrillator. At 2 years of follow-up, we placed her on 200 mg/day of oral amiodarone, after identifying short-coupled premature contractions as the trigger for the ventricular fibrillation. In the 2 years following initiation of this drug therapy, the patient had no further fibrillation episodes.

Syncope caused by coronary artery spasm without chest pain leading to ventricular fibrillation

We present a case of syncope caused by coronary artery spasm without chest pain leading to ventricular fibrillation despite of vasodilator therapy with a calcium channel blocker (CCB). A 68-year-old man presented with two episodes of syncope without chest pain. Ergonovine provocation test induced a diffuse spasm in the right coronary artery (RCA) and subsequently, ventricular fibrillation. Under the therapy with multiple vasodilators including two CCBs, a second ergonovine provocation induced a spasm of the proximal RCA resulting in complete obstruction. Owing to drug-resistant coronary spasm complicated by ventricular fibrillation, an implantable cardioverter defibrillator (ICD) was implanted. This case report highlights the occurrence of syncope caused by coronary artery spasm without chest pain that was refractory to single CCB therapy and needed ICD implantation. Therapy with multiple vasodilators, including two or more CCBs, along with ICD implantation may be required to treat such refractory coronary artery spasms leading to lethal arrhythmia.

Ambulatory electrocardiogram-based T-wave alternans in patients with vasospastic angina during asymptomatic periods

T-wave alternans (TWA) is a useful method for evaluating repolarization abnormalities and as a predictor of life-threatening ventricular arrhythmias. Although life-threatening ventricular arrhythmias are occasionally observed during ischemic attacks in patients with vasospastic angina (VSA), there have been no studies to detect repolarization abnormalities using TWA analysis in these patients during the asymptomatic phase. The aim of this study was to analyze modified moving average (MMA) TWA using Holter recordings in 40 patients with VSA and in 40 control subjects. The incidence of positive TWA was higher in the VSA group than in the control group (24 of 40 [60%] vs 0 of 40 [0%], p <0.01). The value of the maximum MMA TWA was also greater in the VSA group than in the control group (68.6 ± 21 vs 34.0 ± 11 μV, p <0.01). In the VSA group, although there was no significant difference in maximum MMA TWA values between patients with multiple- and single-vessel spasm, patients with ventricular tachycardias had higher values than those without (83.0 ± 15 vs 65.9 ± 20 μV, p <0.05). Patients taking calcium channel blockers exhibited decreased values of maximum MMA TWA compared with subjects not taking these drugs (73.8 ± 18 vs 59.5 ± 21 μV, p <0.05). In conclusion, high values and incidences of TWA events were observed in patients with VSA. In the VSA group, maximum values of MMA TWA were high in patients with ventricular tachycardias but decreased in those taking calcium channel blockers. The results suggest that the patients with VSA during asymptomatic phases exhibit repolarization abnormalities leading to a potential risk for life-threatening arrhythmias.

Clinical implications of provocation tests for coronary artery spasm: safety, arrhythmic complications, and prognostic impact: multicentre registry study of the Japanese Coronary Spasm Association

AIMS

Provocation tests of coronary artery spasm are useful for the diagnosis of vasospastic angina (VSA). However, these tests are thought to have a potential risk of arrhythmic complications, including ventricular tachycardia (VT), ventricular fibrillation (VF), and brady-arrhythmias. We aimed to elucidate the safety and the clinical implications of the spasm provocation tests in the nationwide multicentre registry study by the Japanese Coronary Spasm Association.

METHODS AND RESULTS

A total of 1244 VSA patients (M/F, 938/306; median 66 years) who underwent the spasm provocation tests were enrolled from 47 institutes. The primary endpoint was defined as major adverse cardiac events (MACEs). The provocation tests were performed with either acetylcholine (ACh, 57%) or ergonovine (40%). During the provocation tests, VT/VF and brady-arrhythmias developed at a rate of 3.2 and 2.7%, respectively. Overall incidence of arrhythmic complications was 6.8%, a comparable incidence of those during spontaneous angina attack (7.0%). Multivariable logistic regression analysis demonstrated that diffuse right coronary artery spasm (P < 0.01) and the use of ACh (P < 0.05) had a significant correlation with provocation-related VT/VF. During the median follow-up of 32 months, 69 patients (5.5%) reached the primary endpoint. The multivariable Cox proportional hazard model revealed that mixed (focal plus diffuse) type multivessel spasm had an important association with MACEs (adjusted hazard ratio, 2.84; 95% confidence interval, 1.34-6.03; P < 0.01), whereas provocation-related arrhythmias did not.

CONCLUSION

The spasm provocation tests have an acceptable level of safety and the evaluation of spasm type may provide useful information for the risk prediction of VSA patients.

Therapeutic procedures for coronary vasospasm-induced polymorphic ventricular tachycardia

Coronary vasospasm is an unusual cause of angina and myocardial ischemia, with the potential to provoke acute myocardial infarction, malignant cardiac arrhythmias, and sudden cardiac death. The diagnosis is largely clinical and requires a high index of suspicion. Provocation studies are rarely performed due to the risks of the procedure and the relatively low incidence of disease. A subset of patients does not respond to conventional medical therapy and a paucity of evidence exists to guide therapy. While generally believed a multifocal phenomenon, there have been reports of successful treatment of focal, refractory vasospasm with coronary stent implantation. Furthermore, consideration of an implantable cardioverter defibrillator is warranted when vasospasm is complicated by lethal ventricular arrhythmias.

Circulation: Arrhythmia and Electrophysiology Editors' Picks

The following articles are being highlighted as part of Circulation: Arrhythmia and Electrophysiology's Topic Review series. This series will summarize the most important manuscripts, as selected by the editors, published in Circulation: Arrhythmia and Electrophysiology, Circulation, and the other Circulation subspecialty journals. The studies included in this article represent the most read manuscripts published on the topic of sudden death in 2010 and 2011.