Structural and Functional Coronary Artery Abnormalities in Patients With Vasospastic Angina Pectoris

Pathophysiology of Myocardial Infarction With Nonobstructive Coronary Artery Disease: A Contemporary Systematic Review

Background

Myocardial infarction with nonobstructive coronary artery disease (MINOCA) is defined as acute myocardial infarction (AMI) with angiographically nonobstructive coronary artery disease. MINOCA represents 6% of all AMI cases and is associated with increased mortality and morbidity. However, the wide array of pathophysiological factors and causes associated with MINOCA presents a diagnostic conundrum. Therefore, we conducted a contemporary systematic review of the pathophysiology of MINOCA.

Methods

A comprehensive systematic review of MINOCA was carried out through the utilization of the PubMed database. All systematic reviews, meta-analyses, randomized controlled trials, and cohort studies available in English or French that reported on the pathophysiology of MINOCA published after January 1, 2013 were retained.

Results

Of the 600 identified records, 80 records were retained. Central to the concept of MINOCA is the definition of AMI, characterized by the presence of myocardial damage reflected by elevated cardiac biomarkers in the setting of acute myocardial ischemia. As a result, a structured approach should be adopted to thoroughly assess and address clinically overlooked obstructive coronary artery disease, and cardiac and extracardiac mechanisms of myocyte injury. Once these options have been ruled out, a diagnosis of MINOCA can be established, and the appropriate multimodal assessment can be conducted to determine its specific underlying cause (plaque disruption, epicardial coronary vasospasm, coronary microvascular dysfunction, and coronary embolism and/or spontaneous coronary dissection or supply-demand mismatch).

Conclusions

Integrating a suitable definition of AMI and understanding the pathophysiological mechanisms of MINOCA are crucial to ensure an effective multimodal diagnostic evaluation and the provision of adequate tailored therapies.

Safety and prognostic relevance of acetylcholine testing in patients with stable myocardial ischaemia or myocardial infarction and non-obstructive coronary arteries

BACKGROUND

Intracoronary provocation testing with acetylcholine (ACh) is crucial for the diagnosis of functional coronary alterations in patients with suspected myocardial ischaemia and non-obstructive coronary arteries.

AIMS

Our intention was to assess the safety and predictive value for major adverse cardiovascular and cerebrovascular events (MACCE) in patients presenting with ischaemia with non-obstructive coronary arteries (INOCA) or with myocardial infarction with non-obstructive coronary arteries (MINOCA).

METHODS

We prospectively enrolled consecutive INOCA or MINOCA patients undergoing intracoronary ACh provocation testing.

RESULTS

A total of 317 patients were enrolled: 174 (54.9%) with INOCA and 143 (45.1%) with MINOCA. Of these, 185 patients (58.4%) had a positive response to the ACh test. Complications during ACh provocative testing were all mild and transient and occurred in 29 (9.1%) patients, with no difference between patients with positive or negative responses to ACh testing, nor between INOCA and MINOCA patients. A history of paroxysmal atrial fibrillation, moderate/severe diastolic dysfunction and a higher QT dispersion at baseline electrocardiogram were independent predictors of complications. MACCE occurred in 30 patients (9.5%) during a median follow-up of 22 months. The incidence of MACCE was higher among patients with a positive ACh test (24 [13.0%] vs 6 [4.5%], p=0.017), and a positive ACh test was an independent predictor of MACCE.

CONCLUSIONS

ACh provocation testing is associated with a low risk of mild and transient complications, with a similar prevalence in both INOCA and MINOCA patients. Importantly, ACh provocation testing can help to identify patients at higher risk of future clinical events, suggesting a net clinical benefit derived from its use in this clinical setting.

Coronary Vasospastic Angina: A Review of the Pathogenesis, Diagnosis, and Management

Vasospastic angina (VSA) is an under-appreciated cause of chest pain. It is characterised by transient vasoconstriction of the coronary arteries and plays a significant role in the pathogenesis of stable angina and acute coronary syndromes. Complex mechanistic pathways characterised by endothelial dysfunction and smooth muscle hypercontractility lead to a broad spectrum of clinical manifestations ranging from recurrent angina to fatal arrhythmias. Invasive provocation testing using intracoronary acetylcholine or ergonovine is considered the current gold standard for diagnosis, but there is a wide variation in protocols amongst different institutions. Conventional pharmacological therapy relies on calcium channel blockers and nitrates; however, refractory VSA has limited options. This review evaluates the pathophysiology, diagnostic challenges, and management strategies for VSA. We believe global efforts to standardise diagnostic and therapeutic guidelines will improve the outcomes for affected patients.

Management of ischaemia with non-obstructive coronary arteries (INOCA)

Up to half of patients undergoing elective coronary angiography for the investigation of chest pain do not present with evidence of obstructive coronary artery disease. These patients are often discharged with a diagnosis of non-cardiac chest pain, yet many could have an ischaemic basis for their symptoms. This type of ischaemic chest pain in the absence of obstructive coronary artery disease is referred to as INOCA (ischaemia with non-obstructive coronary arteries). This comprehensive review of INOCA management looks at why these patients require treatment, who requires treatment based on diagnostic evaluation, what clinical treatment targets should be considered, how to treat patients using a personalised medicine approach, when to initiate treatment, and where future research is progressing.

Relation Between Cancer and Vasospastic Angina

INTRODUCTION

Patients with cancer have an increased risk of cardiovascular disease including ischemic heart disease and vice versa. Anticancer drugs and radiotherapy are known to contribute to endothelial injury and vasospasm. However, the relations between vasospastic angina (VSA) and cancer or its treatment are poorly investigated.

METHODS

A total of 786 patients underwent intracoronary acetylcholine (ACh) provocation tests to diagnose VSA. The positive ACh provocation test was defined as angiographic coronary artery spasm accompanied by chest pain and/or ischemic electrocardiographic changes. Patients were divided into active cancer, a history of cancer, and no cancer according to the status of malignancy. The impact of types of cancer, anticancer drugs, and radiotherapy on VSA was evaluated.

RESULTS

Of 786 patients, 38 (4.8%) and 84 (10.7%) had active cancer and a history of cancer, respectively, and 401 (51.0%) were diagnosed as VSA. There was no significant difference in rates of positive ACh test among patients with active cancer, a history of cancer, and no cancer (39.5% vs. 57.1% vs. 50.9%, p = 0.20). Types of cancer and cancer treatment also had no impact on positive ACh provocation test.

CONCLUSIONS

In this cross-sectional observational study, we did not find an association of active and a history of cancer with the diagnosis of VSA. Anticancer treatment including chemotherapy and radiotherapy was not significantly associated with positive ACh provocation test.

Tongxinluo Capsule Combined with Atorvastatin for Coronary Heart Disease: A Systematic Review and Meta-Analysis

Introduction

Coronary heart disease (CHD) is a common clinical cardiovascular disease, and its morbidity and mortality rates are increasing, which brings a serious burden to the family and society. Dyslipidemia is one of the most important risk factors for CHD. However, it is difficult to reduce blood lipids to an ideal state with the administration of a statin alone. Tongxinluo capsule (TXLC), as a Chinese patent medicine, has received extensive attention in the treatment of CHD in recent years. This systematic review and meta-analysis aim to provide evidence-based medicine for TXLC combined with atorvastatin in the treatment of CHD.

Objective

To evaluate systematically the effectiveness and safety of TXLC combined with atorvastatin in the treatment of CHD.

Methods

Seven English and Chinese electronic databases (PubMed, Cochrane Library, Embase, CNKI, VIP, CBM, and Wanfang) were searched from inception to January 2020, to search for randomized controlled trials (RCTs) on TXLC combined with atorvastatin in the treatment of CHD. Two researchers independently screened the literature according to the literature inclusion and exclusion criteria and performed quality assessment and data extraction on the included RCTs. We performed a systematic review following Cochrane Collaboration Handbook and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and using a measurement tool to assess the methodological quality of systematic reviews (AMSTAR 2). The quality of outcomes was evaluated by the Grading of Recommendations Assessment, Development and Evaluation (GRADE). And meta-analysis was performed by Review Manager 5.2.

Results

A total of 15 RCTs with 1,578 participants were included in this review. Compared to atorvastatin treatment, TXLC combined with atorvastatin treatment showed potent efficacy when it came to the effectiveness of clinical treatment (RR = 1.24; 95% CI, 1.18, 1.29; P < 0.00001), total cholesterol (TC; MD = −1.21; 95% CI, −1.53, −0.89; P < 0.00001), triacylglycerol (TG; MD = −0.73; 95% CI, −0.81, −0.65; P < 0.00001), high-density lipoprotein cholesterol (HDL-C; MD = 0.27; 95% CI, 0.23, 0.31; P < 0.00001), low-density lipoprotein cholesterol (LDL-C; MD = –0.72; 95% CI, –0.80, −0.64; P < 0.00001), C-reactive protein (CRP; SMD = −2.06; 95% CI, −2.56, −1.57; P < 0.00001), frequency of angina pectoris (SMD = −1.41; 95% CI, −1.97, −0.85; P < 0.00001), duration of angina pectoris (MD = −2.30; 95% CI, −3.39, −1.21; P < 0.0001), and adverse reactions (RR = 0.84; 95% CI, 0.51, 1.39; P=0.50). No serious adverse events or reactions were mentioned in these RCTs. According to the PRISMA guidelines, although all studies were not fully reported in accordance with the checklist item, the reported items exceeded 80% of all items. With the AMSTAR 2 standard, the methodological quality assessment found that 9 studies were rated low quality and 6 studies were rated critically low quality. Based on the results of the systematic review, the GRADE system recommended ranking method was used to evaluate the quality of evidence and the recommendation level. The results showed that the level of evidence was low, and the recommendation intensity was a weak recommendation.

Conclusions

TXLC combined with atorvastatin in the treatment of CHD can effectively improve the effectiveness of clinical treatment, significantly reduce the frequency and duration of angina pectoris, decrease blood lipids, and improve inflammatory factors. However, due to the low quality of the literature included in these studies and the variability of the evaluation methods of each study, there is still a need for a more high-quality, large sample, multicenter clinical randomized control for further demonstration.

Association between 10-Year Atherosclerotic Cardiovascular Disease Risk and Vascular Endothelial Function in Patients with Vasospastic Angina

BACKGROUND

Endothelial dysfunction is a predictor of atherosclerotic cardiovascular disease (ASCVD) and plays an important role in vasospastic angina (VA).

OBJECTIVES

This study evaluated whether flow-mediated dilation (FMD) is also a good marker of 10-year ASCVD risk (10Y-ASCVDR) in patients with VA.

METHODS

Based on their clinical history and coronary artery diameter stenosis (DS), patients were retrospectively enrolled into VA (DS <50% and positive ergonovine provocation), minor coronary artery disease (mCAD, DS <30%), and significant coronary artery disease (sCAD, DS ≥50%) groups. Endothelial function was evaluated by FMD.

RESULTS

Each group contained 50 patients. The 10Y-ASCVDR was significantly higher in the sCAD group than in the VA and mCAD groups (10.86 ± 7.30, 4.71 ± 4.04, and 4.77 ± 4.30, respectively, p < 0.001). The FMD was significantly higher in the mCAD group than in the VA and sCAD groups (6.37 ± 4.25, 3.10 ± 2.23, and 3.07 ± 1.89, respectively, p < 0.001). A significant correlation was found between the FMD and 10Y-ASCVD in the mCAD group (r = -0.622, p < 0.001) and the sCAD group (r = -0.557, p < 0.001) but not in the VA group (r = -0.193, p = 0.179). After adjusting for potential confounders such as BMI, C-reactive protein, maximal coronary stenosis, and brachial-ankle pulse wave velocity, multivariate analysis showed that FMD was independently associated with 10Y-ASCVDR in all patients. However, when looking only at the VA group, FMD did not correlate independently with 10Y-ASCVDR.

CONCLUSIONS

Unlike mCAD and sCAD, we found no correlation between 10Y-ASCVDR and endothelial function in VA. Thus, our results support that FMD is not a good marker of atherosclerotic cardiovascular risk in VA.

Impairment of platelet NO signalling in coronary artery spasm: role of hydrogen sulphide

BACKGROUND AND PURPOSE

The pathophysiology of coronary artery spasm (CAS), with its associated ischaemic crises, is currently poorly understood and treatment is frequently ineffective. In view of increasing evidence that platelet-based defects may occur in CAS patients, we investigated platelet reactivity in CAS patients and whether symptomatic crises reflect activation of platelet-endothelial interactions.

EXPERIMENTAL APPROACH

CAS patients were evaluated during acute and/or chronic symptomatic phases and compared with healthy control subjects. Inhibition of ADP-induced platelet aggregation by the NO donor sodium nitroprusside (SNP) and plasma concentrations of syndecan 1 (glycocalyx shedding marker), tryptase (mast cell activation marker) and platelet microparticles were measured.

KEY RESULTS

Inhibition of platelet aggregation by SNP was diminished in chronic CAS, with further (non-significant) deterioration during symptomatic crises, whereas plasma concentrations of syndecan 1, tryptase and platelet microparticles increased. Treatment of patients with high-dose N-acetylcysteine (NAC) plus glyceryl trinitrate rapidly increased platelet responsiveness to SNP and decreased plasma syndecan 1 concentrations. The effect of NAC on platelet responsiveness to SNP was confirmed in vitro and mimicked by the H₂ S donor NaHS. Conversely, inhibition of enzymatic production of H₂ S attenuated NAC effect.

CONCLUSION AND IMPLICATIONS

CAS is associated with substantial impairment of platelet NO signalling. During acute symptomatic exacerbations, platelet resistance to NO is aggravated, together with mast cell activation and damage to both vasculature and platelets. NAC, via release of H₂ S, reverses platelet resistance to NO and terminates glycocalyx shedding during symptomatic crises: This suggests that H₂ S donors may correct the pathophysiological anomalies underlying CAS.

Prognostic Impacts of Comorbid Significant Coronary Stenosis and Coronary Artery Spasm in Patients With Stable Coronary Artery Disease

BACKGROUND Stable coronary artery disease is caused by a variable combination of organic coronary stenosis and functional coronary abnormalities, such as coronary artery spasm. Thus, we examined the clinical importance of comorbid significant coronary stenosis and coronary spasm. METHODS AND RESULTS We enrolled 236 consecutive patients with suspected angina who underwent acetylcholine provocation testing for coronary spasm and fractional flow reserve (FFR) measurement. Among them, 175 patients were diagnosed as having vasospastic angina (VSA), whereas the remaining 61 had no VSA (non-VSA group). The patients with VSA were further divided into the following 3 groups based on angiography and FFR: no organic stenosis (≤50% luminal stenosis; VSA-alone group, n=110), insignificant stenosis of FFR>0.80 (high-FFR group, n=36), and significant stenosis of FFR≤0.80 (low-FFR group, n=29). The incidence of major adverse cardiovascular events, including cardiovascular death, nonfatal myocardial infarction, urgent percutaneous coronary intervention, and hospitalization attributed to unstable angina was evaluated. All patients with VSA received calcium channel blockers, and 28 patients (95%) in the low-FFR group underwent a planned percutaneous coronary intervention. During a median follow-up period of 656 days, although the incidence of major adverse cardiovascular events was low and comparable among non-VSA, VSA-alone, and high-FFR groups, the low-FFR group had an extremely poor prognosis (non-VSA group, 1.6%; VSA-alone group, 3.6%; high-FFR group, 5.6%; low-FFR group, 27.6%) (P<0.001). Importantly, all 8 patients with major adverse cardiovascular events in the low-FFR group were appropriately treated with percutaneous coronary intervention and calcium channel blockers. CONCLUSIONS These results indicate that patients with VSA with significant coronary stenosis represent a high-risk population despite current guideline-recommended therapies, suggesting the importance of routine coronary functional testing in this population.

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.

Decreased resting coronary flow and impaired endothelial function in patients with vasospastic angina

OBJECTIVES

Coronary endothelial and circulatory dysfunction plays important roles in the pathogenesis of vasospastic angina (VSA). However, a complete understanding of the entire coronary circulation including microvasculature in patients with VSA is lacking.

PATIENTS AND METHODS

A total of 32 patients without obstructive coronary artery disease in the left descending coronary artery, who underwent an intracoronary acetylcholine (ACh) provocation test for diagnosis of VSA, were enrolled prospectively. A positive diagnosis of the ACh test was defined as total/subtotal coronary artery narrowing accompanied by chest pain and/or ischemic ECG changes. Angina frequency and severity at baseline, and 1 and 3 months were recorded. Coronary circulation was evaluated invasively using a thermodilution method by obtaining the mean transit time (Tmn) at rest and hyperemia, coronary flow reserve, and index of microcirculatory resistance. Systemic endothelial function was assessed by the reactive hyperemia index.

RESULTS

There were 14 (44%) and 18 (56%) patients with and without a positive ACh provocation test. The baseline characteristics did not differ significantly between the two groups. Patients with VSA had a significantly lower reactive hyperemia index compared with those without VSA (1.70±0.33 vs. 2.12±0.53, P=0.02). Coronary flow reserve, index of microcirculatory resistance, and hyperemic Tmn were not different between the two groups, whereas resting Tmn was significantly longer in patients with VSA (1.20±0.44 vs. 0.71±0.37, P=0.002). Although the frequency and severity of angina improved from baseline to 1 and 3 months in patients with both positive and negative ACh tests, there was no difference between the two groups.

CONCLUSION

Patients with VSA had decreased resting coronary flow and impaired endothelial function.

Coronary Artery Spasm: The Interplay Between Endothelial Dysfunction and Vascular Smooth Muscle Cell Hyperreactivity

Patients with angina pectoris, the cardinal symptom of myocardial ischaemia, yet without significant flow-limiting epicardial artery stenosis represent a diagnostic and therapeutic challenge. Coronary artery spasm (CAS) is an established cause for anginal chest pain in patients with angiographically unobstructed coronary arteries. CAS may occur at the epicardial level and/or in the microvasculature. Although the underlying pathophysiological mechanisms of CAS are still largely unclear, endothelial dysfunction and vascular smooth muscle cell (VSMC) hyperreactivity seem to be involved as major players, although their contribution to induce CAS is still seen as controversial. This article will look at the role and possible mechanistic interplay between an impaired endothelial and VSMC function in the pathogenesis of CAS.

Decreased Double Product at Rest in Patients With Severe Vasospasm

BACKGROUND

Autonomic nerve system and endothelial function play important roles in vasospastic angina. Elevated heart rate (HR), blood pressure (BP), and double product (DP) can increase endothelial-dependent coronary artery dilation and blood flow. However, the impact of HR, BP, and DP on occurrence and severity of VSA in the clinical setting is unclear.

METHOD

A total of 170 patients undergoing intracoronary acetylcholine (ACh) provocation test during hospitalisation was included. Resting HR, BP, and DP were measured at least four times, and their variabilities were evaluated by standard deviations (SD) and coefficient of variations (CVs). Angiographic coronary artery vasospasm was defined as total or subtotal occlusion induced by ACh provocation.

RESULTS

Mean±SD HR (65.7±9.1 vs 69.6±7.9 beats per minute; p=0.003), systolic BP (122.3±13.4 vs 127.7±14.6 mmHg; p=0.01), and DP (8,001±1,229 vs 8,903±1,495; p<0.001) were significantly lower in patients with a positive ACh test than the counterpart, whereas SD and CV of both HR and systolic BP were not significantly different between the two groups. Mean HR, BP, and DP progressively decreased with increase in the number of vessels with angiographic vasospasm. Multivariate analysis showed current smoking and lower DP as independent predictors of the greater number of vessels with provoked angiographic vasospasm.

CONCLUSIONS

Resting HR, BP, and DP were lower in patients with vasospastic angina, especially in those with severe vasospasm.

Acute myocardial infarction caused by persistent coronary spasm associated with high-grade macrophage accumulation

The mechanisms responsible for persistent and lethal coronary spasm remain incompletely understood. Our group treated a patient with non-ST-elevation myocardial infarction (MI) caused by a spontaneously persistent spasm associated with high-grade macrophage accumulation. A 48-year-old man was transferred to an emergency room because of persisted chest tightness. The patient's chest pain subsided without ST elevation when he arrived at the hospital, but he tested positive for fatty acid-binding protein. Emergent coronary angiography revealed a subtotal occlusion in the middle of the right coronary artery. The occluded lesion was released immediately after an injection of isosorbide dinitrate. No disruption, ulceration or erosion was observed at the culprit lesion segment on optical coherence tomography. The only finding was high-grade macrophage accumulation in the segment of the persistent focal coronary spasm. The present case suggests that the early stage of atherosclerosis with high-grade macrophage accumulation was associated with persistent coronary spasm resulting in acute MI.

Diagnosis of coronary microvascular dysfunction in the clinic

The coronary microcirculation plays a pivotal role in the regulation of coronary blood flow and cardiac metabolism. It can adapt to acute and chronic pathologic conditions such as coronary thrombosis or long-standing hypertension. Due to the fact that the coronary microcirculation cannot be visualized in human beings in vivo, its assessment remains challenging. Thus, the clinical importance of the coronary microcirculation is still often underestimated or even neglected. Depending on the clinical condition of the respective patient, several non-invasive (e.g. transthoracic Doppler-echocardiography assessing coronary flow velocity reserve, cardiac magnetic resonance imaging, positron emission tomography) and invasive methods (e.g. assessment of coronary flow reserve (CFR) and microvascular resistance (MVR) using adenosine, microvascular coronary spasm with acetylcholine) have been established for the assessment of coronary microvascular function. Individual patient characteristics, but certainly also local availability, methodical expertise and costs will influence which methods are being used for the diagnostic work-up (non-invasive and/or invasive assessment) in a patient with recurrent symptoms and suspected coronary microvascular dysfunction. Recently, the combined invasive assessment of coronary vasoconstrictor as well as vasodilator abnormalities has been titled interventional diagnostic procedure (IDP). It involves intracoronary acetylcholine testing for the detection of coronary spasm as well as CFR and MVR assessment in response to adenosine using a dedicated wire. Currently, the IDP represents the most comprehensive coronary vasomotor assessment. Studies using the IDP to better characterize the endotypes observed will hopefully facilitate development of tailored and effective treatments.

[Prinzmetal angina. Questions of pathogenesis, clinic, diagnosis and treatment]

Current problems of Prinzmetal angina (vasospastic angina, variant angina) considers in this review. Attention is drawn to early diagnosis, which should be comprehensive, taking into account possible atypical courses and the development of complications. The important role of electrocardiographic monitoring (including using implantable recorders) is highlighted. It is emphasized that patients with cardiac arrhythmias, syncope are at high risk of developing sudden cardiac death. In this category of patients, it is recommended to timely determine the indications for implantation of a cardioverter - defibrillator. Authors consider the prospects of using new methods of treatment of angina pectoris.

Coronary artery vasospasm after misoprostol treatment for incomplete abortion: a case report

Misoprostol is widely used for the medical management of incomplete abortion. Few serious adverse events have been reported, so it is considered a safe drug. We present a case of a 40-year-old woman in which misoprostol preceded coronary artery spasm.

Endothelial Function: A Short Guide for the Interventional Cardiologist

An impaired function of the coronary endothelium is an important determinant of all stages of atherosclerosis, from initiation, to mediation of functional phenomena—such as spasm and plaque erosion, to atherothrombotic complications. Endothelial function is modified by therapies, including stent implantation. Finally, endothelial function changes over time, in response to physical stimuli and pharmocotherapies, and its assessment might provide information on how individual patients respond to specific therapies. In this review, we describe the role of the endothelium in the continuum of coronary atherosclerosis, from the perspective of the interventional cardiologist. In the first part, we review the current knowledge of the role of endothelial (dys)function on atherosclerotic plaque progression/instabilization and on the mechanisms of ischemia, in the absence of coronary artery stenosis. In the second part of this review, we describe the impact of coronary artery stenting on endothelial function, platelet aggregation, and inflammation.

Left Main Coronary Artery Diverticulum: Case Report and Review of the Literature

Coronary artery disease is a major cause of morbidity and mortality, and while most commonly is atherosclerotic, it can present with variable manifestations, both congenital and acquired. One such manifestation is coronary aneurysm, which is a localized dilatation of a coronary artery wall segment to greater than 1.5 times the adjacent normal segments. While a dilated outpouching of a coronary artery has been commonly classified as a coronary aneurysm, a non-dilated outpouching is rare and is referred to as a diverticulum, with only one previous case report in the literature. It is conceivable that other cases of coronary artery diverticulum may have been previously reported as an aneurysm, given the overlapping angiographic appearance. We present a case of a 72-year-old female patient with an incidental finding of left main coronary artery diverticulum on diagnostic coronary angiogram done for preoperative liver transplantation evaluation.

Effect of various Danshen injections on patients with coronary heart disease after percutaneous coronary intervention: A protocol for a systematic review and network meta-analysis

BACKGROUND

Patients with coronary heart disease (CHD) who undergo percutaneous coronary intervention (PCI) have a certain risk of vascular complications, including coronary restenosis and thrombosis. Many recent randomized controlled trials have reported that Danshen injection (DSI) combined with conventional Western medicine can significantly reduce the occurrence of major cardiovascular adverse events in patients with CHD after PCI. However, there are many types of DSIs, and no study has yet compared each type. Therefore, we propose a study protocol for the systematic evaluation of the efficacy of various DSIs in the treatment of CHD after PCI.

METHODS

We will search the following electronic databases for randomized controlled trials evaluating the effect of DSI in patients with CHD after PCI: PubMed, Embase, Web of Science, Cochrane Library, Scopus, Ovid Evidence-Based Medicine Reviews, China National Knowledge Infrastructure, and Chinese Biomedicine Literature Database. Each database will be searched from inception to April 2018. The entire process will include study selection, data extraction, risk of bias assessment, pairwise meta-analyses, and network meta-analyses.

RESULTS

This proposed study will compare the efficacy of different DSIs in the treatment of patients with CHD after PCI. The outcomes will include major cardiovascular adverse events and left ventricular ejection fraction.

CONCLUSION

This proposed systematic review will evaluate the different advantages of various types of DSIs in the treatment of patients with CHD after PCI.

REGISTRATION

PROSPERO (registration number: CRD42018092705).

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).

Two-dimensional myocardial deformation in coronary vasospasm-related Takotsubo cardiomyopathy: A case report of a serial echocardiographic study

RATIONALE

Although transient reduction in the left ventricular ejection fraction is characteristic of Takotsubo cardiomyopathy, little is known about the time-course changes of myocardial deformation in coronary vasospasm-related Takotsubo cardiomyopathy.

PATIENT CONCERNS

We retrospectively analyzed the time-course changes in left ventricle, right ventricle, and left atrium strain values in a patient with coronary vasospasm-related Takotsubo cardiomyopathy. We found that not only left ventricular strain but also left atrial strain was abnormal during acute Takotsubo cardiomyopathy due to coronary vasospasm. Right ventricular free wall strain was normal.

DIAGNOSES

Coronary vasospasm-related Takotsubo cardiomyopathy.

INTERVENTIONS

A serial echocardiographic study.

OUTCOMES

The left ventricular strain was still subnormal despite a normalized left ventricular ejection fraction 2 months later. The left atrial strain was normal when the left ventricular ejection fraction normalized.

LESSONS

From this limited experience, it is suggested that echocardiographic myocardial deformation analysis can provide more information than the standard ejection fraction in evaluating myocardial contractile function.

Relation between severity of myocardial bridge and vasospasm

BACKGROUND

Myocardial bridge (MB) has been reported to induce cardiac complications including coronary vasospasm. Although MB has some anatomical and morphological variations, the association of these variations with vasospasm is unclear. The aim of this study was to investigate the relation between morphological severity of MB and vasospasm induced by acetylcholine (ACh) provocation test.

METHODS

A total of 392 patients without coronary stent in the left anterior descending artery (LAD) undergoing intracoronary ACh provocation test were included. Angiographic coronary artery vasospasm was defined as total or subtotal occlusion induced by ACh provocation. MB was identified on coronary angiography as a milking effect. Total bridged length and maximum percent systolic compression of MB in the LAD were analyzed quantitatively.

RESULTS

MBs in the LAD were identified in 140 patients (36%), mostly in the mid segment. Patients with MB in the LAD had greater number of provoked vasospasm in the LAD and positive ACh provocation test compared to those without. The bridged length positively correlated with percent systolic compression of MB (r=0.37, p<0.001). In the receiver operating characteristic curve analysis, both bridged length and percent systolic compression of MB significantly predicted the provoked LAD spasm (AUC 0.74, p<0.001, and AUC 0.68, p<0.001). Multivariate regression analysis demonstrated these factors as independent predictors for provoked LAD spasm.

CONCLUSION

MB, especially morphologically severe MB, may induce greater coronary vasospasm.

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.