Coronary artery spasm--clinical features, diagnosis, pathogenesis, and treatment. J Cardiol. 2008;51:2-17. [PMID: 18522770 DOI: 10.1016/j.jjcc.2008.01.001]

Seasonal and circadian patterns of myocardial infarction by coronary artery disease status and sex in the ACTION Registry-GWTG

BACKGROUND

Myocardial infarction (MI) presentations are more common during winter months and morning hours. However, it is unknown whether MI with obstructive coronary artery disease (MI-CAD) and non-obstructive CAD (MINOCA) display similar patterns.

METHODS

We evaluated seasonal and circadian patterns of MI presentation by coronary artery disease (CAD) status and sex in patients with MI from 2007 to 2014 in the National Cardiovascular Data Registry (NCDR) Acute Coronary Treatment Intervention Outcomes Network (ACTION) Registry-Get With the Guidelines. Adult patients who underwent coronary angiography for MI were included. Patients with missing age, sex, or angiographic data, cocaine use, thrombolytic therapy prior to catheterization, or prior revascularization were excluded. Baseline demographics and characteristics of symptom onset, including season and time of day of presentation, were compared by CAD status and sex.

RESULTS

Among 322,523 patients, 112,547 were female (35%); 18,918 had MINOCA (5.9%). There was no seasonal pattern of MI overall. However, both men and women with MINOCA presented more often in the summer and fall while MI-CAD presentations were equally distributed across seasons. The most common time of presentation was 8 am-2 pm regardless of CAD status or sex. A secondary peak in women with MINOCA during late afternoon hours was also identified.

CONCLUSIONS

Seasonal variation of MI differed between MINOCA and MI-CAD, with a small increase in MINOCA incidence in the summer and fall. MINOCA and MI-CAD most commonly occurred in the morning, with a secondary peak in late afternoon in women with MINOCA. These differences in presentation may relate to underlying MI pathophysiology.

Association of East Asian Variant Aldehyde Dehydrogenase 2 Genotype (ALDH2*2*) with Coronary Spasm and Acute Myocardial Infarction

Coronary spasm plays an important role in the pathogenesis of ischemic heart disease, including angina pectoris, acute myocardial infarction (AMI), silent myocardial ischemia, and sudden death. The prevalence of coronary spasm is higher among East Asians probably due to genetic as well as environmental factors. ALDH2 eliminates toxic aldehydes including 4-hydroxy-2-nonenal (4-HNE) derived from lipid peroxidation and acrolein in tobacco smoking as well as ethanol-derived acetaldehyde and thereby protects tissues and cells from oxidative damage. Deficient variant ALDH2*2 genotype is prevalent among East Asians and is a significant risk factor for both coronary spasm and AMI through accumulation of toxic aldehydes, thereby contributing to oxidative stress, endothelial damage, vasoconstriction, and thrombosis. Toxic aldehydes are thus identified as risk factors to be targeted for the treatment of coronary spasm and AMI.

Coronary artery spasm - Clinical features, pathogenesis and treatment

Coronary artery spasm (CAS) plays an important role in the pathogenesis of ischemic heart disease, including angina pectoris, myocardial infarction, and sudden death, occurring most often from midnight to early morning. CAS is prevalent among East Asians and is associated with an aldehyde dehydrogenase 2 (ALDH2)-deficient genotype (ALDH2*2) and alcohol flushing, which is prevalent among East Asians but is virtually non-existent in other populations. ALDH2 eliminates not only acetaldehyde but also other toxic aldehydes from lipid peroxidation and tobacco smoking, thereby protecting tissues and cells from oxidative damage. Risk factors for CAS include smoking and genetic polymorphisms including those of ALDH2*2, endothelial NO synthase, paraoxonase I, and interleukin-6. Accordingly, oxidative stress, endothelial dysfunction, and low-grade chronic inflammation play an important role in the pathogenesis of CAS, leading to increased coronary smooth muscle Ca²⁺ sensitivity through RhoA/ROCK activation and resultant hypercontraction. Ca-channel blockers blocking the intracellular entry of Ca²⁺ are specifically effective for treatment for CAS.

Associations between Ambient Temperature and Acute Myocardial Infarction

Background

The associations between incidence of acute myocardial infarction (AMI) and the ambient temperature were mixed in prior studies.

Methods

Data of 2033 consecutive admissions of AMI in a central tertiary hospital in North China from 1st Jan 2003 to 31st Dec 2011 were collected. The weather data in this period were from the local meteorological department. Based on the ambient temperature information, we defined several ambient temperature indices, including daily average temperature, extremely low temperature, and daily temperature range, then characterized the independent associations between them and the incidence of AMI.

Results

The daily average temperature one day before was independently associated with AMI incidence rate: a rise of 5°C of the daily average temperature led to a 5% decrease in AMI admissions. Daily average temperature and temperature range two days before were independently associated with AMI incidence rate: a rise of 5°C of the daily average temperature led to a fall of 6% in AMI admissions, and a rise of 2°C of the daily temperature range led to a rise of 4% in AMI admission.

Conclusion

Low ambient temperature has substantial association with AMI, and can play an important role in warning and forecasting the incidence.

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.

The multi-vessel and diffuse coronary spasm is a risk factor for persistent angina in patients received anti-angina medication

Coronary artery spasm (CAS) is known to be a risk factor for cardiovascular events. However, there is limited data whether the multi-vessel and diffuse spasm (MVDS) is related to more adverse clinical outcomes compared to the Non-MVDS. The aim of this study is to evaluate the impact of the MVDS on clinical outcomes during a 3-year clinical follow-up period.A total 2797 patients underwent coronary angiography (CAG) with acetylcholine (ACH) provocation test from Nov 2004 to Oct 2010 were enrolled. It is a single-center, observational, prospective, all-comers registry designed to reflect the "real world" practic. The patients were divided into the 3 groups; the negative spasm (NS) group (n = 1188), the Non-MVDS group (n = 1081), and the MVDS group (n = 528). The incidence of major adverse cardiac events (MACE) and recurrent angina was evaluated up to 3 years. To minimize confounding factors, multivariable Cox-proportional hazards regression analysis was performed.In the 3-year clinical follow-up, the incidence of total death, myocardial infarction, de novo percutaneous coronary intervention (PCI), cerebrovascular accident and MACE were similar among the 3 groups. However, recurrent angina occurred more frequently in the MVDS group than in the NS group (hazard ratio [HR], 1.96; 95% confidence interval [CI], 1.27-3.02; P = .002). Recurrence angina between the MVDS group and the Non-MVDS group was not statistically significant (HR, 1.36; 95% CI, 0.91-2.03; P = .129).In this study, although the incidence of major adverse cardiovascular events were not different regardless of spasm type, the MVDS was associated with higher incidence of recurrent chest pain requiring repeat CAG during the 3-year follow-up period, suggesting more intensive optimal medical therapy with close clinical follow up would be necessary for this particular subset of patients.

Impact of Insulin Resistance on Acetylcholine-Induced Coronary Artery Spasm in Non-Diabetic Patients

PURPOSE

Coronary artery spasm (CAS) and diabetes mellitus (DM) are implicated in endothelial dysfunction, and insulin resistance (IR) is a major etiological cause of type 2 DM. However, the association between CAS and IR in non-diabetic individuals has not been elucidated. The aim of the present study was to evaluate the impact of IR on CAS in patients without DM.

MATERIALS AND METHODS

A total of 330 eligible patients without DM and coronary artery disease who underwent acetylcholine (Ach) provocation test were enrolled in this study. Inclusion criteria included both hemoglobin A1c <6.0% and fasting glucose level <110 mg/dL without type 2 DM. Patients were divided into quartile groups according the level of homeostasis model assessment of insulin resistance (HOMA-IR): 1Q (n=82; HOMA-IR<1.35), 2Q (n=82; 1.35≤HOMA-IR<1.93), 3Q (n=83; 1.93≤HOMA-IR< 2.73), and 4Q (n=83; HOMA-IR≥2.73).

RESULTS

In the present study, the higher HOMA-IR group (3Q and 4Q) was older and had higher body mass index, fasting blood glucose, serum insulin, hemoglobin A1c, total cholesterol, and triglyceride levels than the lower HOMA-IR group (1Q). Also, poor IR (3Q and 4Q) was considerably associated with frequent CAS. Compared with Q1, the hazard ratios for Q3 and Q4 were 3.55 (95% CI: 1.79-7.03, p<0.001) and 2.12 (95% CI: 1.07-4.21, p=0.031), respectively, after adjustment of baseline risk confounders. Also, diffuse spasm and accompanying chest pain during Ach test were more strongly associated with IR patients with CAS.

CONCLUSION

HOMA-IR was significantly negatively correlated with reference diameter measured after nitroglycerin and significantly positively correlated with diffuse spasm and chest pain.

Dehydroepiandrosterone inhibits ICa,L and its window current in voltage-dependent and -independent mechanisms in arterial smooth muscle cells

Dehydroepiandrosterone (DHEA) is an adrenal steroid hormone, which has the highest serum concentration among steroid hormones with DHEA sulfate (DHEAS). DHEA possesses an inhibitory action on glucose-6-phosphate dehydrogenase (G6PD), the first pentose-phosphate pathway enzyme that reduces NADP⁺ to NADPH. DHEA induced relaxation of high K⁺-induced contraction in rat arterial strips, whereas DHEAS barely induced it. We studied the effects of DHEA on L-type Ca²⁺ current ( I_Ca,L) of A7r5 arterial smooth muscle cells and compared the mechanism of inhibition with that produced by the 6-aminonicotinamide (6-AN) competitive inhibitor of G6PD. DHEA moderately inhibited I_Ca,L that was elicited from a holding potential (HP) of -80 mV [voltage-independent inhibition (VIDI)] and accelerated decay of I_Ca,L during the depolarization pulse [voltage-dependent inhibition (VDI)]. DHEA-induced VDI decreased peak I_Ca,L at depolarized HPs. By applying repetitive depolarization pulses from multiple HPs, novel HP-dependent steady-state inactivation curves ( f_∞-HP) were constructed. DHEA shifted f_∞-HP to the left and inhibited the window current, which was recorded at depolarized HPs and obtained as a product of current-voltage relationship and f_∞-HP. The IC₅₀ value of I_Ca,L inhibition was much higher than serum concentration. DHEA-induced VDI was downregulated by the dialysis of guanosine 5'- O-(2-thiodiphosphate), which shifted f_∞-voltage to the right before the application of DHEA. 6-AN gradually and irreversibly inhibited I_Ca,L by VIDI, suggesting that the inhibition of G6PD is involved in DHEA-induced VIDI. In 6-AN-pretreated cells, DHEA induced additional inhibition by increasing VIDI and generating VDI. The inhibition of G6PD underlies DHEA-induced VIDI, and DHEA additionally induces VDI as described for Ca²⁺ channel blockers. NEW & NOTEWORTHY Dehydroepiandrosterone, the most abundantly released adrenal steroid hormone with dehydroepiandrosterone sulfate, inhibited L-type Ca²⁺ current and its window current in aortic smooth muscle cells. The IC₅₀ value of inhibition decreased with the depolarization of holding potential to 15 µM at -20 mV. The inhibition occurred in a voltage-dependent manner as described for Ca²⁺ channel blockers and in a voltage-independent manner because of the inhibition of glucose-6-phosphate dehydrogenase.

Coronary Vasospasm After Burn Injury: First Described Case Series of a Lethal Lesion

Burn injuries generate multisystem physiological derangements. The authors present a case series of three patients developing acute coronary syndrome (ACS) stemming from coronary vasospasm (CVS) over a course of 5 months. This etiology of ACS is significant as it has previously not been described in burn patients and requires a different management algorithm than vaso-occlusive disease.All patients were admitted to a single accredited burn unit. Burn mechanisms were flash burn, chemical fire, and house fire. TBSA were 20%, 72%, and 31%, respectively. Ages were 67-, 41-, and 52-year-old men. All smoked tobacco, and one had diabetes and coronary artery disease. CVS presented with acute onset ST elevations, severe bradycardia, and cardiac arrest in all. Diagnosis was made via EKG and angiography. Treatment was undertaken with nitrates and calcium channel blockers. One of the patients died of refractory disease.The authors identified CVS in burn patients with an incidence of 2% of admissions and accounting for 17% of our burn mortality during this period. To date, there is no linkage between CVS and burns described in humans; however, there is a well-described animal model in rats. The risk factors for CVS are common among burn patients, particularly smoking and endothelial dysfunction. CVS may be a significant cause of ACS in burn patients, and it should be considered in the setting of ACS especially with a negative angiography. Knowledge of this disease state can change burn management to mitigate risk and accommodate specific cardiac treatments.

Downregulated caveolin-1 expression serves a potential role in coronary artery spasm by inducing nitric oxide production in vitro

The present study aimed to investigate the effects of downregulated caveolin-1 (Cav-1) expression on nitric oxide (NO) production in lipopolysaccharide (LPS)-damaged primary human umbilical vein endothelial cells (HUVECs) in a model of coronary artery spasm (CAS) microenvironment induced by acetylcholine (ACh) treatment. Small interfering RNA (siRNA)-mediated Cav-1 downregulation in HUVECs was confirmed by western blotting. The cell viability and superoxide dismutase (SOD) inhibition in HUVECs incubated with LPS (0, 10, 25, 50, 75 and 100 µg/ml) were measured by cell counting kit-8 assay and a SOD kit, respectively. Intracellular Ca2+ [(Ca2+)i] in Fluo4-acetoxymethyl ester-loaded cells was detected by fluorescence microscopy. NO levels in the cell culture supernatants were measured by the nitrate reductase method. The results indicated that transfection with Cav-1 siRNA, in particular siCav-1 (2), downregulated the Cav-1 protein expression. LPS at a dose of 75 µg/ml induced a significant decrease in HUVECs/si-NC and HUVECs/siCav-1 viability compared with the other concentrations of LPS. Compared with the effects of untreated cells, SOD inhibition in HUVECs/si-NC and HUVECs/siCav-1 was significantly decreased by LPS (75 µg/ml). In addition, ACh stimulation caused a greater increase in [Ca2+]i in HUVECs/si-NC as compared with LPS-treated HUVECs/si-NC. ACh stimulation also induced significantly higher NO levels in LPS-treated HUVECs/siCav-1 compared with LPS-treated HUVECs/si-NC cells (P<0.05). In conclusion, the downregulated Cav-1 expression served a key role in NO production in the in vitro model of CAS induced by ACh stimulation of LPS-damaged HUVECs.

Differential prognosis of vasospastic angina according to presentation with sudden cardiac arrest or not: Analysis of the Korean Health Insurance Review and Assessment Service

BACKGROUND

The long-term prognosis of vasospastic angina (VSA) patients presenting with aborted sudden cardiac death (ASCD) is still unknown. We sought to compare the long-term clinical outcomes between VSA patients presenting with and without ASCD by retrospective analysis of a nationwide population-based database.

METHODS

A total of 6972 patients in the Health Insurance Review and Assessment database who were hospitalized in the intensive care unit with VSA between July 1, 2007 and May 31, 2015 were enrolled. Primary outcome was the composite of cardiac arrest and acute myocardial infarction after discharge.

RESULTS

Five hundred ninety-eight (8.6%) VSA patients presented with ASCD. On inverse probability of treatment weighting, ASCD patients had a significantly increased risk of the composite of cardiac arrest and acute myocardial infarction (adjusted hazard ratio, 2.52; 95% confidence interval, 1.72-3.67; p < 0.001) during the median follow-up duration of 4 years. The association of ASCD presentation with a worse outcome in terms of primary outcome was consistent across various subgroups, including comorbidity type and use of vasodilators (all p-values for interaction: non-significant). ASCD patients treated with an implantable cardioverter defibrillator (ICD) had a lower incidence of the composite of cardiac arrest and acute myocardial infarction during follow-up than those without an ICD (p = 0.009).

CONCLUSIONS

VSA patients that present with ASCD are at increased risk of cardiac arrest or myocardial infarction during long-term follow-up despite adequate vasodilator therapy. An ICD is a potential therapeutic option for secondary prevention.

Fatal Vasospasm of the Coronary Arteries in a Patient Undergoing Distal Bypass Surgery and Endovascular Therapy for Threatened Lower Limbs Due to Acute Exacerbation of Peripheral Arterial Disease

A 79-year-old man with a heavy smoking history presented with threatened lower limbs due to acute exacerbation of peripheral artery disease (PAD). He underwent emergent distal bypass surgery for the right leg and external iliac stenting for the left leg. Fatal coronary artery spasm (CAS) with ST segment changes on electrocardiography was observed 28 h after the procedures, resulting in cardiac arrest. Coronary angiography showed widespread CAS with improvement after intra-arterial nitroglycerin infusion. We should keep in mind that CAS may occur more frequently than expected in PAD patients, especially those who have not stopped smoking prior to revascularization.

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.

Increased plasma xanthine oxidoreductase activity deteriorates coronary artery spasm

Increased reactive oxygen species (ROS) contributes to the development of endothelial dysfunction, which is involved in coronary artery spasm (CAS). Xanthine oxidoreductase (XOR) plays a pivotal role in producing both uric acid and ROS. However, the association between plasma XOR activity and CAS has not been elucidated. The aim of this study was to investigate whether plasma XOR activity is associated with CAS. We measured XOR activity in 104 patients suspected for CAS, who presented without significant coronary artery stenosis and underwent intracoronary acetylcholine provocation tests. CAS was provoked in 44 patients and they had significantly higher XOR activity as compared with those without CAS. The patients were divided into three groups based on the XOR activity. The prevalence rate of CAS was increased with increasing XOR activity. A multivariate logistic regression analysis showed that the 3rd tertile group exhibited a higher incidence of CAS as compared with the 1st tertile group [odds ratio (OR) 6.9, P = 0.001) and the 2nd tertile group (OR 3.2, P = 0.033) after adjustment for conventional CAS risk factors, respectively. The C index was significantly improved by the addition of XOR activity to the baseline model based on CAS risk factors. Furthermore, the 3rd tertile group had the highest incidence of severe spasm defined as total obstruction, flow-limiting stenosis, diffuse spasm, multivessel spasm, and/or lethal arrhythmia. This is a first report to elucidate the association of plasma XOR activity with CAS. Increased plasma XOR activity is significantly associated with CAS.

Characteristics, Management, and Outcome of Transient ST-elevation Versus Persistent ST-elevation and Non-ST-elevation Myocardial Infarction

Patients with acute myocardial infarctions (AMIs) present as persistent ST-elevation myocardial infarction (STEMI) or as non-ST-segment elevation myocardial infarction (NSTEMI). In some patients with STEMI, ST elevations are transient and resolve before coronary intervention (transient ST-elevation myocardial infarction [TSTEMI]). We analyzed our registry comprising all consecutive patients with AMI admitted during 2009 to 2014, and compared the characteristics, management, and outcome of patients with TSTEMI with those of patients with STEMI and NSTEMI. Of 1,847 patients with AMI included in the registry, 1,073 patients sustained a STEMI (58%), 649 had a NSTEMI (35%), and 126 presented with TSTEMI (6.9%). Patients with TSTEMI were younger than patients with NSTEMI and STEMI (56.5 vs 62.8, p <0.001, and 59.5 years, p <0.02, respectively), smoked more (77.8 vs 54.0, p <0.001, and 62.1%, p <0.0005), and fewer were hypertensive (52.4 vs 74.2% and 58.8%, both p <0.001) and diabetic (26.2% vs 47.7%, p <0.0001, and 36.9%, p <0.02). The extent of coronary artery disease in patients with TSTEMI was similar to that of patients with STEMI except for less involvement of the left anterior descending artery (p <0.001), but less extensive than in NSTEMI patients. TSTEMI involved less myocardial damage by troponin-T level (p <0.005) with better cardiac function (LVEF 61% vs 55% and 49%, both p <0.0001). Mortality was lower among TSTEMI both in-hospital (0 vs 2.3% [p = NS] and 4.2% [p <0.01]) and long-term (4.8% vs 14.7% and 14.2%, both p <0.003) at a median of 36 months. In conclusion, TSTEMI is an acute coronary syndrome distinct from NSTEMI and STEMI, characterized by fewer risk factors, a similar extent of coronary artery disease to STEMI, but is associated with less myocardial damage and portends a better outcome.

New onset acute pulmonary edema after methylergonovine given during cesarean delivery of a patient with undiagnosed Raynaud's disease

Raynaud's disease is a medical condition in which arterial spasm causes episodes of reduced blood flow, in the setting of certain triggers such as cold weather. Patients with this condition are at risk of adverse reactions if they receive medications with vasoactive properties. Methylergonovine maleate is one drug used during cesarean delivery to treat postpartum hemorrhage due to uterine atony. By acting directly on uterine and vascular smooth muscle, it produces cardiovascular responses such as coronary vasospasm, myocardial infarction, and even cardiac arrest. However, pulmonary events have rarely been reported. We report our anesthetic management of a 36-year-old patient, with undiagnosed Raynaud's disease and undergoing cesarean delivery, who experienced new onset acute pulmonary edema after methylergonovine administration to manage postpartum hemorrhage.

Impact of Trimetazidine Treatment on 5-year Clinical Outcomes in Patients with Significant Coronary Artery Spasm: A Propensity Score Matching Study

OBJECTIVE

We aimed to evaluate the additive benefit of trimetazidine with well-known antispasmodic agents such as calcium channel blockers and nitrate in patients with significant coronary artery spasm (CAS) as assessed by acetylcholine provocation test up to 5 years.

METHODS

A total 1727 patients with significant CAS were enrolled. They were divided into two groups: a trimetazidine group (trimetazidine, diltiazem, and nitrate, n = 695), and control group (diltiazem and nitrate, n = 473). After propensity score matching analysis, two matched groups (441 pairs, n = 882, C-statistic = 0.673) were generated. The individual and composite clinical end points [mortality, myocardial infarction (MI), revascularization, cerebrovascular accident (CVA), major adverse cardiac events (MACE), major adverse cardiac or cerebrovascular events (MACCE), and recurrent angina] were assessed up to 5 years for the two groups.

RESULTS

At 5 years, there were similar incidences of individual and composite hard endpoints including mortality, MI, revascularization, CVA, MACE, MACCE, and recurrent angina in the two groups.

CONCLUSIONS

Additional long-term (5-year) treatment with trimetazidine in combination with diltiazem and nitrate in patients with significant CAS was not associated with improved clinical outcomes compared with combination therapy with diltiazem and nitrate only (without trimetazidine).

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.

Coronary Microcirculatory Dysfunction in Human Cardiomyopathies: A Pathologic and Pathophysiologic Review

Cardiomyopathies are a heterogeneous group of diseases of the myocardium. The term cardiomyopathy involves a wide range of pathogenic mechanisms that affect the structural and functional states of cardiomyocytes, extravascular tissues, and coronary vasculature, including both epicardial coronary arteries and the microcirculation. In the developed phase, cardiomyopathies present with various clinical symptoms: dyspnea, chest pain, palpitations, swelling of the extremities, arrhythmias, and sudden cardiac death. Due to the heterogeneity of cardiomyopathic patterns and symptoms, their diagnosis and therapies are great challenges. Despite extensive research, the relation between the structural and functional abnormalities of the myocardium and the coronary circulation are still not well understood in the various forms of cardiomyopathy. The main pathological characteristics of cardiomyopathies and the coronary microcirculation develop in a progressive manner due to (1) genetic-immunologic-systemic factors; (2) comorbidities with endothelial, myogenic, metabolic, and inflammatory changes; (3) aging-induced arteriosclerosis; and (4) myocardial fibrosis. The aim of this review is to summarize the most important common pathological features and/or adaptations of the coronary microcirculation in various types of cardiomyopathies and to integrate the present understanding of the underlying pathophysiological mechanisms responsible for the development of various types of cardiomyopathies. Although microvascular dysfunction is present and contributes to cardiac dysfunction and the potential outcome of disease, the current therapeutic approaches are not specific for the given types of cardiomyopathy.

Coronary Artery Spasm during Cryoballoon Ablation in a Patient with Atrial Fibrillation

The patient was a 63-year-old man with drug-resistant atrial fibrillation who developed coronary spasm during cryoballoon ablation (CBA). CBA was started from the left inferior pulmonary vein. ST elevations in II, III, and aVf, with reciprocal ST depressions in V2-5, occurred in association with chest pain just after balloon rewarming and deflation, and the patient's blood pressure fell to 50 mmHg. Coronary angiography revealed 90% diffuse stenosis from the orifice of segment 1 to segment 4 in the right coronary artery. The stenosis and ST elevations improved after the intracoronary injection of nitroglycerine. Using continuous peripheral intravenous coronary vasodilation, we electrically isolated the other pulmonary veins with CBA without incident.

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.

A Combination of Tachycardia-Mediated Heart Failure and Coronary Artery Vasospasm-Induced Silent Myocardial Infarction in a Patient with Severe Thyrotoxicosis

Severe thyrotoxicosis can present with a myriad of cardiovascular complications. It may be mild features such as palpitations, tachycardia, and exertional dyspnea or may progress to life-threatening consequences such as atrial fibrillation, tachyarrhythmias, heart failure, myocardial infarction, and shock. In rare cases, they may present with myocardial ischemia secondary to coronary artery vasospasm. We report a case of a 59-year-old Malay gentleman who presented with fast atrial fibrillation and tachycardia-mediated heart failure that evolved to a silent myocardial infarction secondary to severe coronary artery vasospasm with undiagnosed severe thyrotoxicosis. He had complete resolution of heart failure and no further recurrence of coronary artery vasospasm once treatment for thyrotoxicosis was initiated and euthyroidism achieved. This life-threatening consequence has an excellent prognosis if recognised early and treated promptly.

Ergonovine Stress Echocardiography for the Diagnosis of Vasospastic Angina and Its Prognostic Implications in 3,094 Consecutive Patients

Background and Objectives

Ergonovine stress echocardiography (ErgECHO) has been proposed as a noninvasive tool for the diagnosis of coronary vasospasm. However, concern over the safety of ErgECHO remains. This study was undertaken to investigate the safety and prognostic value of ErgECHO in a large population.

Methods

We studied 3,094 consecutive patients from a single-center registry who underwent ErgECHO from November 2002 to June 2009. Medical records, echocardiographic data, and laboratory findings obtained from follow-up periods were analyzed.

Results

The overall positive rate of ErgECHO was 8.6%. No procedure-related mortality or myocardial infarction (MI) occurred. Nineteen patients (0.6%) had transient symptomatic complications during ErgECHO including one who was successfully resuscitated. Cumulative major adverse cardiac events (MACEs) occurred in 14.0% and 5.1% of the patients with positive and negative ErgECHO results, respectively (p<0.001) at a median follow-up of 10.5 years. Cox regression survival analyses revealed that male sex, age, presence of diabetes, total cholesterol level of >220 mg/dL, and positive ErgECHO result itself were independent factors associated with MACEs.

Conclusions

ErgECHO can be performed safely by experienced physicians and its positive result may be an independent risk factor for long-term adverse outcomes. It may also be an alternative tool to invasive ergonovine-provoked coronary angiography for the diagnosis of vasospastic angina.

Acute Myocardial Injury and Complete Atrioventricular Block Induced by Transient Coronary Artery Spasm

A 65-year-old man with no previous history of heart disease presented with cardiogenic shock. Acute right ventricular failure following extensive inferior wall myocardial infarction and complete atrioventricular block were noted and emergent angiography revealed insignificant coronary arterial stenosis. In view of the finding and absence of myocardial vasculitis, coronary artery spasm was implicated as the cause of myocardial infarction and complete atrioventricular block. After the reversal of the shock and successful angioplasty, the patient continued to take lercanidipine and had been angina-free during follow-up of 5 months. (Hong Kong j.emerg.med. 2013;20:396-399)

Acute Myocardial Injury and Complete Atrioventricular Block Induced by Transient Coronary Artery Spasm

A 65-year-old man with no previous history of heart disease presented with cardiogenic shock. Acute right ventricular failure following extensive inferior wall myocardial infarction and complete atrioventricular block were noted and emergent angiography revealed insignificant coronary arterial stenosis. In view of the finding and absence of myocardial vasculitis, coronary artery spasm was implicated as the cause of myocardial infarction and complete atrioventricular block. After the reversal of the shock and successful angioplasty, the patient continued to take lercanidipine and had been angina-free during follow-up of 5 months. (Hong Kong j.emerg.med. 2013;20:396-399)

Assessing Vessel Tone during Coronary Artery Spasm by Dual-Acquisition Multidetector Computed Tomography Angiography

BACKGROUND

Diminished vascular tone is an established biomarker of heart damage. Little is known about the extent of coronary vessel tone (CVT) with spasm as assessed by dual-acquisition multidetector computed tomography angiography (MCTA) in patients with vasospastic angina (VSA).

OBJECTIVE

We evaluated the CVT modulated by intravenous nitrate injection (INI) using MCTA imaging in VSA patients.

METHODS

Twenty-one VSA patients (60 ± 9 years; 76% males) who underwent initial MCTA (without morning vasodilation), followed by an intracoronary ergonovine provocation test were included. Within 3 days after the initial MCTA patients received INI followed by 28-vessel segment spasm analyzed by MCTA 3D software, applying the following formula as the definition of CVT index (CVTI): (CSAIV nitrate - CSAinitial/CSAIV nitrate) ×100 %, where CSA is the cross-sectional area.

RESULTS

Compared to the initial MCTA measures, the INI provocation resulted in the significant increase of average diameter and CSA at the spasm site (2.60 mm [2.11-3.16] vs. 1.42 mm [1.13-2.13]; 5.37 mm2 [3.67-7.54] vs. 1.62 mm2 [1.02-3.02]; p < 0.001). The CVTI at the spastic segments was higher than at the proximal reference segments (41.0% [21.8-52.3] vs. 18.8% [5.9-26.6] for CVTI diameter; 65.1% [38.6-77.0] vs. 33.9% [5.2-48.1] for CVTI CSA, respectively). To predict VSA, the cut-off value for CVTI diameter was 38.6% (AUC 0.777; 95% CI 0.653-0.901) and 62.5% (AUC 0.779; 95% CI 0.657-0.902) for CVTI CSA in a receiver-operating characteristic curve analysis, with 57.1% sensitivity and 92.9% specificity.

CONCLUSIONS

This novel imaging technique for assessing CVT by dual-acquisition MCTA after applying INI provocation is suitable for the detection of coronary artery spasm in patients with VSA.

Spontaneous Left Main and Right Coronary Artery Spasm in a Patient With Vasospastic Angina

Coronary spasm is a well-documented, though rare, condition that can mimic myocardial infarction and is usually found in only a single vessel during an event. We describe the case of a 43-year-old male with past medical history of hypertension, hyperlipidemia, tobacco abuse, and with no known coronary disease. The patient developed chest pain 3 days postadmission for primary diagnosis of psychiatric disorder. The patient had a positive stress study with moderate reversible ischemia in the anterolateral region. A subsequent coronary angiography was performed that revealed significant left main coronary obstruction with TIMI I (thrombolysis in myocardial infarction) flow. This pattern was also present in the proximal right coronary artery. Both stenoses were relieved with intracoronary nitroglycerin, revealing no significant obstructive disease and TIMI III flow. The patient was started on dihydropyridine calcium channel blocker and counseled against smoking without recurrence of 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.

Uric Acid Level Has a U-shaped Association with Clinical Outcomes in Patients with Vasospastic Angina

No data are available on the association of serum uric acid and vasospastic angina (VSA) which has endothelial dysfunction as a possible pathophysiologic mechanism. Low uric acid level might cause adverse outcomes in VSA in connection with endothelial dysfunction. We enrolled 818 VSA patients whose uric acid level was measured at admission. Patients were categorized according to tertiles of uric acid level: group I, ≤ 4.8 mg/dL; group II, 4.9-5.9 mg/dL; and group III, ≥ 6.0 mg/dL. Primary outcome was major adverse cardiac events (MACEs), defined as a composite of cardiac death, acute myocardial infarction (MI), ischemic stroke, coronary revascularization, and rehospitalization for angina. Median follow-up duration was 49.2 months. Median uric acid values were 4.1 mg/dL for group I, 5.4 mg/dL for group II, and 6.7 mg/dL for group III. In the overall population, group II had a significantly lower incidence of MACE compared to group I (47 [17.1%] vs. 66 [24.6%]; hazard ratio [HR], 1.52; 95% confidence interval [CI], 1.02-2.26; P = 0.040) and a tendency of lower incidence of MACEs compared to Group III (47 [17.1%] vs. 62 [22.5%]; HR, 1.44; 95% CI, 0.98-2.13; P = 0.067). Among group I patients, those who received nitrates had a higher incidence of MACEs than those without nitrate therapy (P < 0.001). Low uric acid level was associated with adverse clinical outcomes, while high uric acid level had a trend toward an increase in it. Use of nitrate in patients with low uric acid level might have adverse effects on clinical outcomes of VSA.

Prinzmetals angina presenting with non critical lesion with normal FFR -to stent or not to stent

Variant angina also called Prinzmetals angina is an enigma characterized by transient circadian symptoms of chest pain associated with ECG changes. The patient is symptom free with normal ECG and echo during symptom free periods. We present a case associated with transient ST-segment elevation with non critical lesion with normal FFR.

Ultra-long acting calcium channel blockers may decrease accuracy of the acetylcholine provocation test

BACKGROUND

When drug-induced coronary spasm provocation tests are performed, a washout period of >48h for calcium channel blockers (CCBs) is uniformly recommended. However, each CCB has a distinct half-life, and little is known about the influence of prior oral administration of CCBs on acetylcholine provocation test to evaluate coronary vasomotor reaction.

METHODS AND RESULTS

We examined 245 consecutive patients with suspected vasospastic angina who had undergone acetylcholine provocation test. Of those patients, 29 patients had been on amlodipine, an ultra-long term acting CCB (group A), 34 on other CCBs (group O), and 182 patients on no CCB (group N). After CCBs had been withheld > 48h, we performed acetylcholine provocation, which resulted in 152 positive, 36 intermediate, and 57 negative reactions. We evaluated coronary artery tone calculated as follows: (luminal diameter after nitrate-baseline luminal diameter)÷(luminal diameter after nitrate)×100 (%). In group A patients, coronary artery tone was lower (A:9.1±6.9% vs. O:11.7±8.3% vs. N:12.1±8.5%, p=0.0011) and the positive rate of acetylcholine provocation test was lower than group O and group N (A:41% vs. O:68% vs. N:64%, p=0.047). Multivariate logistic analysis showed that taking amlodipine until 2days before acetylcholine provocation test was a significant inverse predictor for acetylcholine-provoked coronary spasm (odds ratio 0.327; 95% confidence interval 0.125-0.858, p=0.023).

CONCLUSIONS

Residual vasodilatory effects of ultra-long acting CCB may decrease coronary artery tone and the vasoconstrictive reaction to acetylcholine suggesting that a 2-day pre-test drug holiday may not be long enough.

Incidence and factors associated with mortality in 2,476 patients with variant angina in Korea

This study investigated the incidence and risk factors of mortality in 2,476 patients with variant angina (VA) using the National Health Insurance Service–National Sample Cohort between 2004 and 2011. The risk factors of all-cause and cardiac mortality were investigated using Cox proportional hazards model. Most patients (69.5%) were less than 65 years and 42.9% were women. During the median follow-up duration of 4.9 years, there were 178 (7.2%) and 95 (3.8%) cases of all-cause and cardiac mortality, respectively. Older age, hypertension, diabetes mellitus, poor medication adherence, low household income and tertiary teaching hospitals were independent predictors for all-cause mortality, while older age, hypertension, low household income and tertiary teaching hospitals were independent predictors for cardiac mortality. In conclusion, our findings suggest that traditional risk factor control and continued medication are important to improve VA outcomes, and that household income-level factors should be considered in the assessment of risk of VA patients.

Importance of a second spasm provocation test: Four cases with an initial negative spasm provocation test

The spasm provocation test (SPT) is an important test in the diagnosis of vasospastic angina (VSA). In many cases, this test is performed as the gold standard test, and VSA is considered not present if the SPT is negative. However, some patients continue to experience chest symptoms despite a negative SPT. In this study, we report four cases in which SPT was repeated to evaluate chest symptoms despite the negative results of the first SPT. Two men in their 70s, one woman in her 60s, and one woman in her 70s, all with chest symptoms, underwent a second SPT at 4, 3, 2, and 3 years, respectively, after the first SPT, which was negative. Three patients had positive results in the second SPT (75%). In conclusion, even when SPT is negative, the diagnosis of VSA should be made with clinical symptoms in consideration. In some cases, a second SPT may be required to confirm the diagnosis of VSA.

Aborted Sudden Cardiac Death in a Female Patient Presenting with Takotsubo-Like Cardiomyopathy due to Epicardial Coronary Vasospasm

Takotsubo cardiomyopathy is characterized by apical ballooning of the left ventricle (LV) in the absence of relevant coronary artery stenosis, which typically occurs in elderly women after emotional stress. Catecholamine cardiotoxicity, metabolic disturbance, and coronary microvascular impairment have previously been proposed as underlying pathophysiologic mechanisms of takotsubo cardiomyopathy, whereas myocardial stunning resulting from epicardial coronary artery vasospasm is not generally accepted as a cause of takotsubo cardiomyopathy. The prognosis of takotsubo cardiomyopathy is generally more favourable compared to myocardial infarction; however, severe complications such as rupture of the LV and life-threatening arrhythmias may occur. Herein, we describe a case of an 84-year-old female, who presented with aborted sudden cardiac death due to ventricular fibrillation. Echocardiography suggested LV apical ballooning with severely impaired LV-function, so that takotsubo cardiomyopathy was suspected. However, coronary angiography revealed epicardial spasm of the left anterior ascending, which resolved after intracoronary injection of 0.2 mg nitroglycerine. Cardiac magnetic resonance exhibited subendocardial late enhancement and echocardiography showed normalization of LV dysfunction during follow-up. The patient was put on conservative treatment with nitrates and calcium inhibitors and ICD implantation were deferred.

Parallel comparison of risk factors between progression of organic stenosis in the coronary arteries and onset of acute coronary syndrome by covariance structure analysis

Background

It is widely accepted that progression of organic stenosis in the coronary arteries and onset of acute coronary syndrome (ACS) are similar in the development of atherosclerosis. However, the extent of the association of each risk factor with the respective pathological conditions has not been fully elucidated.

Objectives

We investigated the differences in risk factors between these conditions using a statistical procedure.

Methods

The study population consisted of 1,029 patients with ischemic heart disease (IHD). We divided the study population into two groups (ACS and non-ACS) and by diseased vessels (organic stenosis). Covariance structure analysis was simultaneously performed in one equation model for determination and comparison of the risk factors for organic stenosis and ACS.

Results

The analysis revealed that age (standardized regression coefficient, β: 0.206, P < 0.001), male gender (β: 0.126, P < 0.001), HbA1c level (β: 0.109, P < 0.001), HDL level (β: -0.109, P < 0.001) and LDL level (β: 0.127, P = 0.002) were significant for the advancement of organic stenosis. HDL level (β: 0100, P = 0.002) and MDA-LDL level (β: 0.335, P < 0.001) were significant for the onset of ACS, but age, HbA1c and LDL (P = NS or β < 0.1, respectively) were not. Among the risk factors, age, HbA1c and LDL were significantly more strongly associated with organic stenosis than ACS, while MDA-LDL was significantly more strongly associated with ACS than organic stenosis.

Conclusions

The current statistical analysis revealed clear differences among the risk factors between the progression of organic stenosis and the onset of ACS. Among them, the MDA-LDL level should be considered to indicate a substantial risk of ACS.

Fluctuations in the amplitude of ST-segment elevation in vasospastic angina: Two case reports

RATIONALE

ST-segment elevation localizes an ischemic lesion to the coronary artery supplying the area of the myocardium reflected by the electrocardiographic leads. Dynamic ST-segment elevation can be due to severe transmural ischemia secondary to a thrombus, vasospasm, or a tightly fixed coronary artery lesion or a combination of these situations.

PATIENT CONCERNS

In this study, we report on two patients with angina who had fluctuations in ST-segment amplitude on serial electrocardiograms. The amplitude of ST-segment elevation varied between 1-20 mm.

DIAGNOSES

Vasospastic angina (VSA) was diagnosed based on electrocardiography and coronary angiography.

INTERVENTIONS

Calcium antagonists were prescribed for both patients.

OUTCOMES

No recurrent VSA was noted during outpatient follow-up.

LESSONS

VSA can be associated with fluctuations in the amplitude of ST-segment elevation, indicating dynamic coronary vasospasm in different locations and extensions in patients with VSA.

Omega-3 and omega-6 DPA equally inhibit the sphingosylphosphorylcholine-induced Ca2+-sensitization of vascular smooth muscle contraction via inhibiting Rho-kinase activation and translocation

We previously reported that eicosapentaenoic acid (EPA), an omega-3 polyunsaturated fatty acid (n-3 PUFA), effectively inhibits sphingosylphosphorylcholine (SPC)-induced Ca²⁺-sensitization of vascular smooth muscle (VSM) contraction which is a major cause of cardiovascular and cerebrovascular vasospasm, and EPA is utilized clinically to prevent cerebrovascular vasospasm. In this study, we clearly demonstrate that docosapentaenoic acid (DPA), which exists in two forms as omega-3 (n-3) and omega-6 (n-6) PUFA, strongly inhibits SPC-induced contraction in VSM tissue and human coronary artery smooth muscle cells (CASMCs), with little effect on Ca²⁺-dependent contraction. Furthermore, n-3 and n-6 DPA inhibited the activation and translocation of Rho-kinase from cytosol to cell membrane. Additionally, SPC-induced phosphorylation of myosin light chain (MLC) was inhibited in n-3 and n-6 DPA pretreated smooth muscleVSM cells and tissues. In summary, we provide direct evidence that n-3 and n-6 DPA effectively equally inhibits SPC-induced contraction by inhibiting Rho-kinase activation and translocation to the cell membrane.