Prevalence of Coronary Microvascular Disease and Coronary Vasospasm in Patients With Nonobstructive Coronary Artery Disease: Systematic Review and Meta-Analysis

Rationale and design of the women's ischemia syndrome evaluation mechanisms of coronary microvascular dysfunction leading to preheart failure with preserved ejection fraction (WISE Pre-HFPEF)

BACKGROUND

There is increasing recognition that the pathophysiology of coronary microvascular dysfunction (CMD) plays a pivotal role in the development of heart failure with preserved ejection fraction (HFpEF). However, the mechanisms underlying this role are not known.

STUDY DESIGN AND METHODS

The Women's Ischemia Syndrome Evaluation Mechanisms of Coronary Microvascular Dysfunction Leading to Pre-Heart Failure With Preserved Ejection Fraction (WISE Pre-HFpEF) is a prospective cohort study enrolling 180 women and men undergoing clinically indicated invasive coronary angiography for suspected ischemia with no obstructive coronary artery disease. The study aims to investigate (1) CMD-related ischemia contribution to myocellular damage and impaired left ventricular (LV) relaxation as determined invasively by ultra-high sensitivity cardiac troponin I (u-hs-cTnI) measurements in the coronary sinus/great cardiac vein and LV pressure-volume loops, respectively, during provocative stress testing with isometric handgrip, and (2) CMD-related ischemic myocellular damage contribution to LV diastolic dysfunction progression as assessed using cardiac magnetic resonance imaging obtained at enrollment and 1-2 years later, along with prospectively repeated ambulatory u-hs-cTnI measurements.

CONCLUSIONS

The WISE pre-HFpEF study is designed to investigate whether ischemic myocardial damage secondary to CMD contributes to the progression of LV diastolic dysfunction. The findings from this study will provide new understanding of the role of CMD in HFpEF development as well as the potential benefits of CMD-directed therapies for the prevention and treatment of HFpEF.

TRIAL REGISTRATION

ClilicalTrial.gov, NCT03876223.

Safety, Feasibility, and Diagnostic Yield of Invasive Coronary Function Testing: Netherlands Registry of Invasive Coronary Vasomotor Function Testing

Importance

Patients with angina and no obstructive coronary artery disease frequently have coronary vasomotor dysfunction as underlying pathophysiological mechanism, comprising epicardial spasm, microvascular spasm, and/or microcirculatory dysfunction. These endotypes can be diagnosed by invasive coronary function testing which has previously shown to be safe in tertiary and expert centers.

Objective

To determine the prevalence of vasomotor dysfunction in patients with angina and no obstructive coronary artery disease who were clinically referred for a coronary function test (CFT); and assess safety and feasibility of a CFT.

Design, Setting, and Participants

This quality improvement study was performed using the Netherlands Registry of Invasive Coronary Vasomotor Function Testing (NL-CFT), a prospective, observational registry, in 15 participating hospitals (2 tertiary and 13 nontertiary). Patients with angina and no obstructive coronary artery disease who were referred for a clinically indicated CFT between December 2020 and January 2024 were included.

Main Outcomes and Measures

A complete CFT consisted of acetylcholine spasm provocation testing and assessment of microcirculatory function. Prevalence of different endotypes based on test results and overall safety were assessed.

Results

Among a total of 1207 patients included, 978 (81%) were female; and the mean (SD) age was 60 (10) years. The prevalence of coronary vasomotor dysfunction was very high (78%). There were 11 (0.9%) major and 10 (0.8%) minor complications reported. Of them, 3 major and all minor were definitely related to the coronary function test. No procedural death, myocardial infarction, or stroke was observed. No differences were found in the occurrence of complications between tertiary and nontertiary centers.

Conclusions and Relevance

This study found that a CFT was feasible and safe to perform in both tertiary and nontertiary centers with a high diagnostic yield.

Ischemia with no obstructed coronary arteries and microvascular testing procedures: a review of utility, pharmacotherapy, and current challenges

Ischemia with no obstructive coronary arteries (INOCA) is an increasingly recognized condition in patients presenting with angina and positive stress tests but without significant coronary artery stenosis. This review addresses the pathophysiology, diagnostic approaches, and management strategies associated with INOCA, emphasizing epicardial coronary spasms and coronary microvascular dysfunction (CMD) as underlying mechanisms and myocardial bridging (MB) as a risk factor. Diagnostic modalities include both non-invasive techniques and invasive procedures, such as acetylcholine provocation testing, to differentiate vasospasm from microvascular causes. The paper discusses a potential interference between vasodilators used in trans-radial access and coronary spasm testing. Long-term management approaches for INOCA patients, including pharmacologic therapies and lifestyle interventions, are reviewed.

Inverse association between CALLY index and angina pectoris in US adults: a population-based study

BACKGROUND

The C-reactive protein-albumin-lymphocyte (CALLY) index is a significant marker that reflects both inflammatory and nutritional states and has proven to be a valuable tool for assessing prognosis in various medical conditions. However, the connection between it and angina pectoris has not yet been fully examined. This research sought to thoroughly investigate the possible link between the CALLY index and angina pectoris.

METHODS

This research utilized a cross-sectional approach, drawing data from the 2003-2010 National Health and Nutrition Examination Survey (NHANES), which included 16,291 adults from the U.S. The CALLY index was calculated based on lymphocyte counts, serum albumin concentrations, and C-reactive protein (CRP) levels. The relationship between the CALLY index and angina pectoris was analyzed using multivariate logistic regression and restricted cubic spline (RCS) methods. Subgroup and interaction analyses were also performed.

RESULTS

Elevated ln CALLY was inversely correlated with the prevalence of angina (OR: 0.88, 95% CI: 0.82, 0.95). Those in the highest quartile of the ln CALLY (Q4) were 38% less likely to experience angina than those in the lowest quartile (Q1) (OR: 0.62, 95% CI: 0.46, 0.84). RCS analysis revealed an L-shaped curve linking the CALLY index to angina, with a cutoff at 14. The consistency of this relationship was substantiated through subgroup analyses across different population groups.

CONCLUSIONS

This research highlights a notable inverse relationship between the CALLY index and angina in U.S. adults, suggesting its potential as an innovative tool for evaluating angina.

Coronary Microvascular Dysfunction and Vasospastic Angina-Pathophysiology, Diagnosis and Management Strategies

Coronary artery disease is one of the leading public health problems in the world in terms of mortality and economic burden from the disease. Traditionally, the focus of research and clinical pathways leading to the diagnosis and treatment of coronary artery disease was on the more common variant of the disease resulting from atherosclerosis in the epicardial coronary arteries. However, coronary microvasculature, representing the vast majority of the total heart circulation, has the greatest influence on overall coronary resistance and, therefore, blood flow. Coronary microvascular dysfunction (CMD), characterized by structural or functional abnormalities in the microvasculature, significantly impacts myocardial perfusion. Endothelial dysfunction results in inadequate coronary dilation during exercise or spontaneous spasm in the microvasculature or epicardial arteries. A significant proportion of people presenting for coronary angiography in the context of angina have unobstructed epicardial coronary arteries yet are falsely reassured about the benign nature of their condition. Meanwhile, increasing evidence indicates that patients diagnosed with CMD as well as vasospastic angina (VSA) face an increased risk of Major Adverse Cardiovascular Events (MACEs), including death. The aim of this review is to outline the current practice with regard to invasive and non-invasive methods of CMD and VSA diagnosis and assess the evidence supporting the existing treatment strategies. These include endotype-specific pharmacological therapies, a holistic approach to lifestyle modifications and risk factor management and novel non-pharmacological therapies. Furthermore, the review highlights critical gaps in research and suggests potential areas for future investigation, to improve understanding and management of these conditions.

Exercise electrocardiogram combined with cadmium zinc tellurium (CZT) cardiac-dedicated single photon emission computed tomography (SPECT) predicts coronary artery disease

AIM

Coronary artery disease (CAD) is a primary cause of mortality, prompting ongoing research into noninvasive diagnostic modalities. This study aimed to evaluate the diagnostic efficacy of exercise electrocardiography testing (EET) combined with cadmium zinc tellurium cardiac-dedicated single photon emission computed tomography (CZT-SPECT) imaging for CAD.

MATERIALS AND METHODS

CZT-SPECT and EET were examined in 124 patients aged 20-85 years, followed by coronary angiography to evaluate the sensitivity, specificity, positive predictive value, and negative predictive value of EET/CZT-SPECT alone and in combination. CAD was defined as the presence of > 50% stenosis at the time of coronary angiography.

RESULTS

The sensitivity of the EET test alone was 31.58%, the specificity was 80%, the positive predictive value (PPV) was 22.22%, and the negative predictive value (NPV) was 86.6%. The corresponding values of CZT-SPECT alone were 36.07%, 92.06%, 81.48% and 59.79%, respectively. The combined results showed that the sensitivity, specificity, PPV, and NPV were 60.00%, 90.57%, 54.55%, and 92.31%, respectively. In this study, the positive likelihood ratio (PLR) diagnosed with EET alone was 1.58, the PLR diagnosed with CZT-SPECT alone was 4.54, and the PLR diagnosed with combination was 6.36.

CONCLUSION

The combination of CZT-SPECT and EET showed significantly improved CAD diagnostic accuracy compared with either approach alone.

Coronary microvascular dysfunction endotypes: IMR tips and tricks

Coronary microvascular dysfunction (CMD) is an important clinical disease spectrum which has gained widespread attention due to chronic anginal symptoms, and worse clinical outcomes, with or without obstructive coronary artery disease (CAD). Coronary microcirculatory dysfunction is due to a wide array of mechanisms such as inflammation, platelet aggregation, vessel wall collagen deposition, imbalance of nitric oxide, free radicals, and sympathetic/parasympathetic simulation. As noted in this supplement, CMD can occur as a primary disease or co-exist with multi-array of diverse cardiac conditions such as CAD (old infarct), hypertrophic cardiomyopathy, Takotsubo cardiomyopathy, hypertension, or infiltrative diseases. CMD, which is often under diagnosed, leads to increase in medical expenses, decrease in quality of life, exacerbation of underlying conditions such as heart failure and even increased mortality. CMD presents a challenge for patients as well as physicians to manage. In this chapter, we review CMD and focus on its endotypes, techniques for microcirculatory assessment, associated tips and tricks and available treatment options.

Evolution of Coronary Microvascular Dysfunction Prevalence over Time and Across Diagnostic Modalities in Patients with ANOCA: A Systematic Review

Background: A considerable number of patients with angina undergo invasive coronary angiography, which might reveal non-obstructive coronary arteries (ANOCA). In this setting, they might have coronary microvascular disease (CMD). Its prevalence significantly varies in the literature. This systematic review aims to document the prevalence of CMD over time according to the diagnostic modalities. Methods: A systematic literature review was conducted using PubMed, the Cochrane Library, and Embase, covering publications from inception to 1 May 2024. Among 1471 identified articles, 297 full-text articles were assessed for eligibility. All studies reporting the prevalence of CMD in ANOCA patients based on invasive coronary artery (ICA), positron emission tomography-computed tomography (PET-CT), transthoracic echocardiography (TTE), or cardiac magnetic resonance (CMR) were included. Results: The review included 53 studies (published between 1998 and 2024), encompassing a total of 16,602 patients. Of these studies, 23 used ICA, 15 used PET-CT, 8 used TTE, and 7 used CMR. A statistically significant increase in CMD prevalence over time was observed across all diagnostic modalities (p < 0.05), except for PET-CT, which showed a consistent and stable prevalence over time. Notably, the prevalence rates from all of the diagnostic methods converged towards the 50% prevalence detected by PET-CT. Conclusions: The prevalence of CMD in patients with ANOCA is subject to debate. However, the current data suggest that regardless of the diagnostic method used, the most recent studies tend to converge towards a prevalence value of 50%, which has been consistently reported by PET-CT from the beginning.

Non-atherosclerotic coronary causes of myocardial infarction in women

Ischemic heart disease is the most common cardiovascular cause of death in women worldwide. Obstructive coronary atherosclerosis is the primary cause of myocardial infarction (MI), however, non-atherosclerotic mechanisms of MI, such as spontaneous coronary artery dissection, vasospasm, microvascular dysfunction, embolization, inflammation, coronary anomalies, infectious and infiltrative causes are increasingly being recognized. Emerging data suggest that women are two to five times more likely to have an MI in the absence of coronary atherosclerosis compared to men, but they continue to remain underdiagnosed and undertreated, partly due to underdiagnosis and limited understanding of these mechanisms. Recent advancements in invasive and noninvasive imaging techniques and physiological testing allow for distinguishing these mechanisms from each other, providing a definitive diagnosis and tailored treatment. This review summarizes the existing literature on the non-atherosclerotic coronary causes of MI with a focus on evidence pertaining to women, offering a basis for future studies.

Known yet underdiagnosed: Invasive assessment of coronary microvascular disease and its implications

Coronary microvascular disease (CMD) is one of the commonest causes of cardiac chest pain. The condition is more prevalent in women, and incidence is known to increase with age, hypertension, and diabetes. The pathophysiological pathways are heterogenous and related to intrinsic vascular and endothelial dysfunction. Furthermore, this entity is known to be associated with adverse cardiovascular outcomes. Despite this, there is inertia amongst cardiologists to further evaluate patients with non-critical coronary artery disease and suspected CMD. With refinement in technology, we have now better understanding of CMD and invasive testing in the catheterization laboratory is a viable option for confirming the diagnosis of CMD. However, despite advances in diagnosing and stratifying this entity, therapeutic options remain limited and poorly defined. In this editorial, we will briefly focus on the pathophysiology and invasive assessment and therapeutic options available for CMD.

The correlation between cumulative cigarette consumption and infarction-related coronary spasm in patients with ST-segment elevation acute myocardial infarction across different age groups

Coronary artery spasm (CAS) is a key contributor to the pathogenesis of acute ST-segment elevation myocardial infarction (STEMI). While smoking is recognized as a major risk factor for CAS, the relationship between cumulative cigarette consumption and infarction-related CAS across different age groups in STEMI patients remains unclear. This study aimed to investigate the correlation between cumulative cigarette consumption and infarction-related CAS across different age groups through a retrospective analysis. This retrospective study included STEMI patients who underwent coronary angiography (CAG) at the General Hospital of Southern Theater Command, between December 2014 and March 2018. STEMI was diagnosed based on the 2017 European Society of Cardiology (ESC) guidelines. Patients were divided into CAS and non-CAS groups according to CAG results, and further categorized by age into three groups: young (≤ 45 years), middle-aged (46-59 years), and elderly (≥ 60 years). Cumulative cigarette consumption was calculated using the smoking index (cigarettes/day × years). Smoking status was graded as follows: grade 0 (non-smokers), grade 1 (index ≤ 100), grade 2 (index > 100 and ≤ 200), and grade 3 (index > 200). Statistical analyses, including Chi-square tests, Spearman correlation, and multivariate logistic regression were conducted to evaluate the relationship between smoking and CAS in different age groups. Among the 1156 STEMI patients analyzed, 80 (6.9%) were diagnosed with CAS. The CAS group exhibited a higher proportion of young adults (35.0% vs. 13.8%, P < 0.001) and grade 3 smokers (62.5% vs. 46.6%, P < 0.001) compared to the non-CAS group. A positive correlation between cumulative cigarette consumption and CAS was observed in all patients (r = 0.124, P < 0.001), heavy smoking (grade 2 and grade 3) was significantly associated with CAS in young adults (r = 0.321, P < 0.001) and middle-aged adults (r = 0.127, P = 0.006) but not in elderly patients. Logistic regression demonstrated that heavy smoking significantly increased CAS risk, with adjusted odds ratios of 6.397 for grade 2 smokers and 6.926 for grade 3 smokers, relative to non-smokers. Among heavy smokers( grade 2 and grade 3), young adults had a 4.912-fold higher CAS risk, while middle-aged adults had a 2.041-fold higher risk, compared to elderly individuals. Cumulative cigarette consumption is closely linked to infarction-related CAS in STEMI patients. Heavy smoking (grade 2 and grade 3) is a key factor linked to infarction-related coronary spasm, especially in younger and middle-aged adults. Effective smoking control is essential for preventing and managing STEMI, particularly among younger and middle-aged populations in China. Further validation of our findings using prospective studies and large registries is warranted.

Coronary Microvascular Dysfunction: Insights on Prognosis and Future Perspectives

Coronary microvascular dysfunction (CMD) comprises a wide spectrum of structural and/or functional abnormalities of coronary microcirculation that can lead to myocardial ischemia. Emerging evidence has indicated that CMD is a relevant cause of morbidity and mortality and is associated with a high risk of major adverse cardiovascular events (MACEs) and heart failure with preserved ejection fraction as well as poor quality of life. This review aims to elucidate briefly the pathogenesis and diagnostic modalities of CMD and to shed light on contemporary evidence on the prognostic impact of CMD. Finally, we will provide an overview of novel emerging therapeutic strategies for CMD.

Association Between Nocturnal Hypoxemia Parameters and Coronary Microvascular Dysfunction: A Cross-Sectional Study

Objective

There is a connection between obstructive sleep apnea (OSA) and coronary microvascular dysfunction (CMD), but the underlying mechanisms remain unclear. This study aims to evaluate the correlation between OSA-related nocturnal hypoxemia parameters and CMD.

Methods

This is an observational, single-center study that included patients who underwent polysomnography and coronary angiography during hospitalization. The presence of CMD was determined by angio-based index of microcirculatory resistance (AccuIMR). Categorical variables were compared using chi-square test or Fisher exact test. The t-test and Mann-Whitney U-test were used to compare normally and non-normally distributed continuous variables, respectively. Univariate and multivariable logistic regression analyses were performed to evaluate the relationship between nocturnal hypoxemia parameters and CMD.

Results

A total of 133 patients were included in this study, of whom 72 (54.14%) had evidence of CMD. Patients with CMD exhibited a higher prevalence of OSA and experienced more severe nocturnal hypoxia. After adjusting for potential confounding factors, minimum oxygen saturation (minSpO2) ≤90% (OR 5.89; 95% CI 1.73-19.99; P=0.004) and the percentage of time spent with oxygen saturation below 90% (T90) ≥5% (OR 3.13; 95% CI 1.05-9.38; P=0.041) were independently associated with CMD. However, no significant association was observed between apnea-hypopnea index (AHI) and CMD.

Conclusion

Parameters of nocturnal hypoxemia are associated with CMD. Hypoxemia parameters may more sensitively reflect the correlation between OSA and CMD than AHI.

Coronary vasomotor response incidence to intracoronary acetylcholine provocation test according to the severity of insignificant coronary artery stenosis in Korean population

BACKGROUND

Coronary artery spasm (CAS) is a cause of variant angina. However, the understanding of CAS patterns in the presence of mild-to-moderate coronary artery stenosis is limited. This study aimed to evaluate the incidence and patterns of CAS in patients with insignificant coronary artery stenosis using intracoronary acetylcholine (ACH) provocation test.

METHODS

In this study, 6513 patients without significant coronary artery stenosis who underwent intracoronary ACH provocation test were enrolled. Patients were divided into three groups, based on the severity of coronary artery stenosis: the non group (stenosis <30%, n = 2833), the mild group (30-49%, n = 3278) and the moderate group (50-69%, n = 402). Vasomotor responses were observed among three different groups.

RESULTS

The baseline characteristics of the patients in the mild and moderate groups were worse than in the non group. They were older, had higher prevalence of hypertension, diabetes, dyslipidemia, and smoking habit. During the ACH test, CAS was observed in 58.1% of the overall population. The mild group (60.1%) and the moderate group (60.9%) showed a higher incidence than the non group (55.3%, P < 0.001). In addition, among cases of CAS, the mild group (3.2%) and the moderate group (8.5%) responded more at a lowest dose of ACH than the non group (3.1%, P < 0.001).

CONCLUSION

In patients with chest pain without significant coronary artery stenosis, CAS was observed in over half of the cases. Furthermore, CAS was found to be more frequent and more susceptible in patients with mild-to-moderate coronary artery stenosis compared with those without fixed stenosis.

MiRNA-34a, miRNA-145, and miRNA-222 Expression, Matrix Metalloproteinases, TNF-α and VEGF in Patients with Different Phenotypes of Coronary Artery Disease

The development of different phenotypes of coronary artery (CA) lesions is regulated via many various factors, such as pro-inflammatory agents, zinc-dependent endopeptidases, growth factors and circulating microRNAs (miRs). To evaluate the expression levels of miR-34a, miR-145 and miR-222, tumor necrosis factor α (TNF-α), matrix metalloproteinases (MMP-1, -9, -13 and -14) and vascular endothelial growth factor (VEGF) in patients with different phenotypes of coronary artery disease (CAD): ischemia/angina with non-obstructive coronary arteries (INOCA/ANOCA) and obstructive CAD (oCAD) compared with a control group. This cross-sectional observational study included 157 subjects with a verified CAD diagnosis (51 patients with INOCA, 76 patients with oCAD and 30 healthy volunteers). The expression of miR-34a, miR-145 and miR-222 (RT-PCR) and the levels of VEGF, TNF-α, MMP-1, MMP-9, MMP-13 and MMP-14 (ELISA) were estimated in plasma samples. A higher concentration of MMP-9 was found in oCAD-group samples compared to the INOCA/ANOCA group. The INOCA/ANOCA group was characterized by higher levels of TNF-α. Based on multivariate regression analysis, a mathematical model predicting the type of CA lesion was constructed. MiR-145 was the independent predictor of INOCA/ANOCA (p = 0.006). Changes in concentrations of MMP-9 and MMP-14 were found in both investigated CAD groups, with MMP-9 levels being significantly higher in obstructive CAD samples than in INOCA/ANOCA, which confirms the role of inflammation in the development of atherosclerosis. A multivariate regression analysis allowed us to achieve a model that can predict the phenotype of stable CAD, and MiR-145 can be assumed as an independent predictor of INOCA/ANOCA.

Cross-Sectional Analyses to Assess the Clinical Safety and Effectiveness of Bisoprolol in Patients With Non-obstructive Coronary Artery Disease Who Underwent Percutaneous Coronary Intervention: A Post-hoc Analysis

INTRODUCTION

Elevated central aortic pressure, cardiac output and peripheral vascular resistance contribute to high morbidity in relation to end organ dysfunction in obstructive and non-obstructive coronary artery disease (NOCAD) cases despite revascularization. Bisoprolol preempts further progression of left ventricular dysfunction in such cases due to anti-ischemic and anti-hypertensive effects, further extending its evaluation in local Indian settings.

METHODS

Post-hoc analyses of NOCAD patients with epicardial stenosis (N=378, 30 to 70% stenosis) from cross-sectional analyses conducted across eighty centers in India. Local ethics approval for study documents and endpoints for analyses was conducted in adherence to ICH-Good Clinical Practice (GCP) and Declaration of Helsinki guidelines. Descriptive and analytical statistics were performed using SPSS Version 29.0.1.0 (IBM Corp., Armonk, NY, USA).

RESULTS

Per-protocol analyses of NOCAD (N=378) showed (mean) age: 58.63 years (286 males and 92 females); mean weight: 75.49kg; mean BMI: 27.78kg/m2 and baseline left ventricular ejection fraction (LVEF): (46.85%). Prevalent risk factors include hypertension (100%), dyslipidemia (51.85%), smoking (24.07%), type 2 diabetes (59.52%), stroke (20.37%) and peripheral artery disease (4.76%). In overall population (n=800), bisoprolol (2.5 to 5mg/day) showed significant reduction in resting heart rate (RHR) (14bpm), and LVEF (5.08%). Similarly, in NOCAD cases significant changes in RHR (12.14bpm), and LVEF (4.68%) were noted at 24 weeks. Adverse events included chest congestion (6.61%), asthenia (5.03%), hypotension (4.76%), muscular weakness (3.70%), and bradycardia (1.85%) that were mild to moderate with none requiring treatment withdrawal.

CONCLUSION

Bisoprolol remains a clinically feasible option in Indian patients with NOCAD cases following percutaneous coronary intervention (PCI) as it reduces RHR and improves LVEF. Despite high rates of cardiovascular risk factors like age, type 2 diabetes and diffuse polyvascular disease, the drug was well-tolerated, with fewer adverse events. These results support the use of bisoprolol in managing NOCAD in Indian patients, highlighting its potential therapeutic uses to prevent further cardiac dysfunction.

Coronary angiography: a review of the state of the art and the evolution of angiography in cardio therapeutics

Traditionally, coronary angiography was restricted to visual estimation of contrast-filled lumen in coronary obstructive diseases. Over the previous decades, considerable development has been made in quantitatively analyzing coronary angiography, significantly improving its accuracy and reproducibility.  Notably, the integration of artificial intelligence (AI) and machine learning into quantitative coronary angiography (QCA) holds promise for further enhancing diagnostic accuracy and predictive capabilities. In addition, non-invasive fractional flow reserve (FFR) indices, including computed tomography-FFR, have emerged as valuable tools, offering precise physiological assessment of coronary artery disease without the need for invasive procedures. These innovations allow for a more comprehensive evaluation of disease severity and aid in guiding revascularization decisions. This review traces the development of QCA technologies over the years, highlighting key milestones and current advancements. It also explores prospects that could revolutionize the field, such as AI integration and improved imaging techniques. By addressing both historical context and future directions, the article underscores the ongoing evolution of QCA and its critical role in the accurate assessment and management of coronary artery diseases. Through continuous innovation, QCA is poised to remain at the forefront of cardiovascular diagnostics, offering clinicians invaluable tools for improving patient care.

The Belgian Registry on Coronary Function Testing (BELmicro Registry): Study Population, Prevalence of Coronary Vascular Dysfunction, and Procedural Safety

Coronary function testing (CFT) plays a pivotal role in the diagnosis of coronary vascular dysfunction and providing patients with tailored therapy. The Belgian registry on CFT (BELmicro registry) is a prospective, observational, multicenter registry including 14 centers in Belgium. All patients who underwent clinically indicated CFT were included in the registry. Baseline characteristics, CFT data, and clinical outcomes were collected. This analysis aimed to describe the baseline characteristics of a real-world population of patients who underwent CFT, evaluate the prevalence of coronary vascular dysfunction, and assess the safety of CFT in daily clinical practice. Between October 2021 and September 2023, 449 patients were enrolled. The mean age was 65 ± 10 years, and 47.4% of patients were men. A total of 59% of patients had hypertension, 18.7% had diabetes, 69.5% had hypercholesterolemia, and 40.1% had a smoking habit. Angina and nonobstructive coronary arteries (ANOCAs) were identified in 85.1% of the patients. Microvascular physiology assessment was performed in 95.5% of patients, vasoreactivity test in 28.5%, and both in 24.0%. coronary microvascular dysfunction was diagnosed in 23.4% of patients with ANOCA, epicardial vasospasm in 26.3%, and microvascular spasm in 14.9%. Rates of major complications were 0.7% for microvascular physiology assessment and 0% for vasoreactivity test. In conclusion, participants in the BELmicro registry represented a real-world population of patients, characterized by a high burden of cardiovascular risk factors. Coronary microvascular dysfunction and coronary vasospasm were frequent in patients with ANOCA. Performing CFT in daily clinical practice was feasible, with a low rate of complications.

Unusual Recurrent Multivessel Coronary Artery Spasm: A Case Report and Literature Review

Coronary artery spasms (CAS) can manifest in various forms, from silent ischemia to severe cardiac events like myocardial infarction and sudden death. This case involves a 56-year-old male with recurrent ischemic chest pain and varying ECG signs. Cardiac catheterization revealed multiple coronary spasms that resolved spontaneously or with intracoronary nitroglycerin. The report emphasizes the severe presentations of multiple CAS and the importance of thorough diagnostic evaluation to avoid unnecessary interventions, highlighting the diagnostic challenges in managing such cases.

Association between the non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) and angina pectoris in US adults: a cross-sectional retrospective study based on NHANES 2009-2018

BACKGROUND

The non-high-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (NHHR) plays a potential role in cardiovascular diseases. However, its association with angina pectoris remains unclear. Herein, we aimed to explore their relationship.

METHODS

This cross-sectional retrospective study included the 2009-2018 data from 22,562 adults diagnosed with angina pectoris, retrieved from the National Health and Nutrition Examination Survey (NHANES) database. NHHR was estimated from laboratory data, and angina pectoris diagnosis was ascertained from the NHANES questionnaire.

RESULTS

Angina pectoris risk was greater in the highest than in the lowest NHHR tertile (odds ratio [OR] = 1.61; 95% confidence interval (CI), 1.15-2.54; P = 0.006). Weighted logistic regression showed a positive association between NHHR and angina pectoris in the fully adjusted model (OR = 1.17; 95% CI, 1.07-1.28; P = 0.001). Restricted cubic spline analysis showed a linear association (P = 0.6572). Subgroup analyses indicated no significant differences across different stratifications (P > 0.05, all). Random forest analyses and Boruta algorithm corroborated that NHHR is a strong predictor of angina pectoris. Among the eight machine-learning models evaluated for predictive capabilities, the logistic regression model demonstrated the strongest predictive capability, with an area under the curve of 0.831.

CONCLUSIONS

Our study suggests that NHHR is a risk factor for angina pectoris and may be used for risk prediction and to inform future intervention programs to reduce its incidence.

Diagnostic Yield and Clinical Utility of Coronary Angiography Versus Coronary Function Testing in Women With Angina and Nonobstructive Coronary Arteries

BACKGROUND

Approximately 50% of women referred for invasive coronary angiography have angina and nonobstructive coronary arteries, which includes coronary microvascular dysfunction, vasospastic angina, and other vasomotor disorders. We sought to determine the real-world diagnostic yield of invasive coronary angiography and coronary function testing in women with angina and nonobstructive coronary arteries.

METHODS AND RESULTS

From 2018 to 2023, we enrolled 198 women who underwent either coronary angiography (CA) alone (n=99) or coronary function testing (CFT; n=99). Mean±SD age was 62±10 years (CA alone) compared with 57±10 years (CFT). Coronary angiography was interpreted as nonobstructive coronary artery disease more frequently after CA alone (79% versus 52%). Of the women who underwent CFT, 82% (N=81) were found to have vasomotor disorders, including coronary microvascular dysfunction (27%), vasospastic angina (32%), mixed coronary microvascular dysfunction/vasospastic angina (16%), endothelial dysfunction (10%; without spasm), elevated resting flow (2%), or symptomatic myocardial bridging (4%). Compared with women undergoing CA alone, medications were changed more frequently after CFT at 24 hours (41% versus 65%; P=0.001) and between 24 hours and 30 days (30% versus 44%; P=0.04) with intensification of antianginal therapy (79% versus 92%; P<0.0001) and increased use of calcium channel blockers (36% versus 63%; P<0.0001).

CONCLUSIONS

Our findings demonstrate that women presenting with suspected ischemic heart disease undergoing CA alone only received an anatomic diagnosis, whereas >80% of women undergoing CFT received a specific diagnosis of a coronary vasomotor disorder and greater intensification of antianginal therapy.

Coronary microvascular disease in women: epidemiology, mechanisms, evaluation, and treatment

Coronary microvascular dysfunction (CMD) involves functional or structural abnormalities of the coronary microvasculature resulting in dysregulation of coronary blood flow (CBF) in response to myocardial oxygen demand. This perfusion mismatch causes myocardial ischemia, which manifests in patients as microvascular angina (MVA). CMD can be diagnosed non-invasively via multiple imaging techniques or invasively using coronary function testing (CFT), which assists in determining the specific mechanisms involving endothelium-independent and dependent epicardial and microcirculation domains. Unlike traditional coronary artery disease (CAD), CMD can often occur in patients without obstructive atherosclerotic epicardial disease, which can make the diagnosis of CMD difficult. Moreover, MVA due to CMD is more prevalent in women and carries increased risk of future cardiovascular events. Successful treatment of symptomatic CMD is often patient-specific risk factor and endotype targeted. This article aims to review newly identified mechanisms and novel treatment strategies for managing CMD, and outline sex-specific differences in the presentation and pathophysiology of the disease.

Comparative study of myocardial perfusion and coronary flow velocity reserve derived from adenosine triphosphate stress myocardial contrast echocardiography in coronary lesions with no/mild stenosis

Background

Qualitative myocardial perfusion (QMP) derived from myocardial contrast echocardiography reflects the capillary flow, while coronary flow velocity reserve from Doppler spectrum (D-CFVR) of the left anterior descending coronary artery (LAD) is used to assess coronary microvascular function, particularly after excluding severe epicardial coronary stenosis. The present study aimed to assess the relationship of QMP and D-CFVR in detecting coronary microvascular disease (CMVD) by using adenosine triphosphate stress myocardial contrast echocardiography (ATP stress MCE).

Methods and results

Seventy-two patients (mean age: 54.22 ± 12.78 years) with chest pain and <50% coronary stenosis diagnosed by quantitative coronary angiography or dual-source CT underwent ATP stress MCE. The distribution of myocardial perfusion and CFVR value was estimated by experienced physicians. Of the 72 LAD with 0%-50% diameter stenosis, 15 (21%) exhibited abnormal CFVR and 31 (43%) displayed abnormal perfusion with ATP stress MCE. Eleven of the 15 LAD territories (73%) with abnormal CFVR values showed abnormal perfusion. However, CFVR was considered normal in 20 LAD territories (35%), despite the presence of perfusion defect in the territory.

Conclusion

Abnormal myocardial perfusion during ATP stress MCE was found in a sizable percentage of patients in whom CFVR of the supplying vessel was considered normal.

ANOCA updated: From pathophysiology to modern clinical practice

Lately, a large number of stable ischemic patients, with no obstructed coronary arteries are being diagnosed. Despite this condition, which is being described as angina with no obstructive coronary arteries (ANOCA), was thought to be benign, recent evidence report that it is associated with increased risk for adverse cardiovascular outcomes. ANOCA is more frequent in women and, pathophysiologically, it is predominantly related with microvascular dysfunction, while other factors, such as endothelial dysfunction, inflammation and autonomic nervous system seem to also play a major role to its development, while other studies implicate ANOCA and microvascular dysfunction in the pathogenesis of heart failure with preserved ejection fraction. For establishing an ANOCA diagnosis, measurement including coronary flow reserve (CFR), microvascular resistance (IMR) and hyperemic microvascular resistance (HMR) are mostly used in clinical practice. In addition, new modalities, such as optical coherence tomography (OCT) are being tested and show promising results for future diagnostic use. Regarding management, pharmacotherapy consists of a wide selection of drugs, according to the respected pathophysiology of the disease (vasospastic angina or microvascular dysfunction), while research for new treatment options including interventional techniques, is currently ongoing. This review, therefore, aims to provide a comprehensive analysis of all aspects related to ANOCA, from pathophysiology to clinical managements, as well as clinical implications and suggestions for future research efforts, which will help advance our understanding of the syndrome and establish more, evidence-based, therapies.

Myocardial contrast echocardiography evaluation of coronary microvascular dysfunction to Predict MACEs in patients with heart failure with preserved ejection fraction follow-up

BACKGROUND

CMD refers to the abnormalities of the tiny arteries and capillaries within the coronary artery system, which result in restricted or abnormal blood flow. CMD is an important mechanism involved in ischemic heart disease and secondary heart failure. CMD can explain left ventricular dysfunction and poor prognosis.The European Association of Cardiovascular Imaging recommends the use of MCE for the assessment of myocardial perfusion. Myocardial contrast echocardiography (MCE) is used to evaluate the accuracy of Coronary microvascular dysfunction (CMD) for predicting major adverse cardiac events (MACEs) in patients with heart failure with preserved ejection fraction (HFpEF) at follow-up.

METHODS

The clinical data of 142 patients diagnosed with HFpEF in our hospital from January 2020 to January 2022 were retrospectively summarized and stratified into 77 cases (> 1) in the CMD group and 65 cases (= 1) in the non-CMD group based on the perfusion score index (PSI) of the 17 segments of the left ventricle examined by the admission MCE, and the perfusion parameters were measured at the same time, including the peak plateau intensity (A value), the curve slope of the curve rise (βvalue) and A × β values. At a median follow-up of 27 months till October 2023, MACEs were recorded mainly including heart failure exacerbation, revascularization, cardiac death, etc. RESULTS: Increasing age, hypertension, diabetes, and coronary artery disease in the CMD group resulted in decreased left ventricular ejection fraction (LVEF), increased plasma NT-B-type natriuretic peptide (BNP) and left ventricular global longitudinal strain (LVGLS), decreased A-values and A × β-values, and an increased incidence of MACEs (P < 0.05). Univariate and multivariate Cox regression analyses showed that LVGLS (HR = 1.714, 95% CI = 1.289-2.279, P < 0.001) and A × β values (HR = 0.636, 95% CI = 0.417 to 0.969, P = 0.035) were independent predictors of MACEs in patients with HFpEF. The receiver operating characteristic curve (ROC) showed that the area under the curve (AUC) of LVGLS combined with A × β value for diagnosis of MACEs was 0.861 (95% CI = 0.761 ~ 0.961, P < 0.001), which was significantly higher than that of LVGLS or A × β value (P < 0.05). The Kaplan-Meier survival curves showed that the cumulative survival rate in CMD group was significantly lower than non-CMD group (logrank χ2 = 6.626, P = 0.010), with the most significant difference at 20 months of follow-up.

CONCLUSION

MCE can evaluate CMD semi-quantitatively and quantitatively, LVGLS combined with A × β value has good performance in predicting the risk of developing MACEs in patients with HFpEF at 3 years of follow-up, and CMD can be used as an important non-invasive indicator for assessing clinical prognosis.

Novel diagnostic approaches and management of coronary microvascular dysfunction

The mechanism underlying ischaemic heart disease (IHD) has been primarily attributed to obstructive coronary artery disease (CAD). However, non-obstructive coronary arteries are identified in >50% of patients undergoing elective coronary angiography, recently leading to growing interest in the investigation and management of angina/ischaemia with non-obstructive coronary arteries (ANOCA/INOCA). INOCA is an umbrella term encompassing a multiple spectrum of possible pathogenetic entities, including coronary vasomotor disorders which consist of two major endotypes: coronary microvascular dysfunction (CMD) and vasospastic angina. Both conditions can coexist and be associated with concomitant obstructive CAD. Particularly, CMD refers to myocardial ischaemia due to reduced vasodilatory capacity of coronary microcirculation secondary to structural remodelling or impaired resting microvascular tone (functional) or a combination of both. CMD is not a benign condition and is more prevalent in women presenting with chronic coronary syndrome compared to men. In this setting, an impaired coronary flow reserve has been associated with increased risk of major adverse cardiovascular events. ANOCA/INOCA patients also experience impaired quality of life and associated increased healthcare costs. Therefore, research in this scenario has led to better definition, classification, and prognostic stratification based on the underlying pathophysiological mechanisms. The development and validation of non-invasive imaging modalities, invasive coronary vasomotor function testing and angiography-derived indices provide a comprehensive characterisation of CMD. The present narrative review aims to summarise current data relating to the diagnostic approach to CMD and provides details on the sequence that therapeutic management should follow.

Spectrum of Non-Obstructive Coronary Artery Disease and Its Relationship with Atrial Fibrillation

This article aims to analyze the relationship between non-obstructive coronary artery disease (NOCAD) and atrial fibrillation (AF), exploring the underlying pathophysiological mechanisms and implications for clinical management. NOCAD and AF are prevalent cardiovascular conditions that often coexist, yet their interrelation is not well understood. NOCAD can lead to ischemic necrosis of cardiomyocytes and their replacement with fibrous tissue, sustaining focal ectopic activity in atrial myocardium. Atrial fibrillation, on the other hand, the most common sustained cardiac arrhythmia, is able to accelerate atherosclerosis and increase oxygen consumption in the myocardium, creating a mismatch between supply and demand, and thus promoting the development or worsening of coronary ischemia. Therefore, NOCAD and AF seem to be a complex interplay with one begets another.

Acute myocardial infarction caused by vasospasm of a jailed diagonal branch subsequent to stent implantation in the left anterior descending artery: a case report

Background

Coronary stents have been reported to cause endothelial dysfunction, potentially leading to spasm at the edges of the stent. However, the clinical significance of vascular spasm in stent-jailed side branches remains poorly understood.

Case summary

A 67-year-old woman was referred to our hospital for angina occurring both during exercise and at rest. An everolimus-eluting stent was implanted for a physiologically significant stenosis in the proximal left anterior descending artery, while an intermediate stenosis persisted in the jailed first diagonal branch. Although her exertional angina resolved, her rest symptoms worsened after percutaneous coronary intervention (PCI). She was admitted with acute myocardial infarction 1 month later. Urgent coronary angiography showed no stent failure, but an acetylcholine provocation test induced a spasm leading to total occlusion of the jailed diagonal branch. An additional stent was implanted in the diagonal branch due to a residual stenosis even after isosorbide dinitrate administration. After the second PCI, her chest pain completely resolved.

Discussion

This is the first documentation of aggregated coronary spasm observed at the ostium of stent-jailed side branch. Stent implantation may induce endothelial dysfunction and promote inflammation, leading to spasms particularly at stent edges. This phenomenon can extend to side branches jailed by the stent, and invasive intervention may be a viable therapeutic strategy for such cases.

PFAS and their association with the increased risk of cardiovascular disease in postmenopausal women

Cardiovascular diseases (CVDs) are one of the major causes of death globally. In addition to traditional risk factors such as unhealthy lifestyles (smoking, obesity, sedentary) and genetics, common environmental exposures, including persistent environmental contaminants, may also influence CVD risk. Per- and polyfluoroalkyl substances (PFASs) are a class of highly fluorinated chemicals used in household consumer and industrial products known to persist in our environment for years, causing health concerns that are now linked to endocrine disruptions and related outcomes in women, including interference of the cardiovascular and reproductive systems. In postmenopausal women, higher levels of PFAS are observed than in premenopausal women due to the cessation of menstruation, which is crucial for PFAS excretion. Because of these findings, we explored the association between perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), and perfluorobutanesulfonic acid in postmenopausal women from our previously established CVD study. We used liquid chromatography with tandem mass spectrometry, supported by machine learning approaches, and the detection and quantification of serum metabolites and proteins. Here, we show that PFOS can be a good predictor of coronary artery disease, whereas PFOA can be an intermediate predictor of coronary microvascular disease. We also found that the PFAS levels in our study are significantly associated with inflammation-related proteins. Our findings may provide new insight into the potential mechanisms underlying the PFAS-induced risk of CVDs in this population. This study shows that exposure to PFOA and PFOS is associated with an increased risk of cardiovascular disease in postmenopausal women. PFOS and PFOA levels correlate with amino acids and proteins related to inflammation. These circulating biomarkers contribute to the etiology of CVD and potentially implicate a mechanistic relationship between PFAS exposure and increased risk of cardiovascular events in this population.

Evaluating Ischemic Heart Disease in Women: Focus on Angina With Nonobstructive Coronary Arteries (ANOCA)

Ischemic heart disease (IHD) is common in women, and cardiovascular disease is a leading cause of morbidity and mortality. While obstructive coronary artery disease is the most common form of IHD, millions of women suffer from angina with nonobstructive coronary arteries (ANOCA), an umbrella term encompassing multiple nonatherosclerotic disorders of the coronary tree. The underlying pathology leading to ischemia in these syndromes may be challenging to diagnose, leaving many women without a diagnosis despite persistent symptoms that impact quality of life and adversely affect long-term cardiovascular prognosis. In the last decade, there have been significant advances in the recognition and diagnostic evaluation of ANOCA. Despite these advances, the standard approach to evaluating suspected IHD in women continues to focus predominantly on the assessment of atherosclerotic coronary artery disease, leading to missed opportunities to accurately diagnose and treat underlying coronary vasomotor disorders. The goal of this review is to describe advances in diagnostic testing that can be used to evaluate angina in women and present a pragmatic diagnostic algorithm to guide evaluation of ANOCA in symptomatic patients. The proposed approach for the assessment of ANOCA is consistent with prior expert consensus documents and guidelines but is predicated on the medical interview and pretest probability of disease to inform a personalized diagnostic strategy.

Exploring the mechanisms of Guizhifuling pills in the treatment of coronary spastic angina based on network pharmacology combined with molecular docking

Coronary spastic angina (CSA) is common, and treatment options for refractory vasospastic angina are sometimes limited. Guizhifuling pills (GFP) have demonstrated efficacy in reducing CSA episodes, but their pharmacological mechanism remains unclear. To explore the mechanism of action of GFP in preventing and treating CSA, we employed network pharmacology and molecular docking to predict targets and analyze networks. We searched GFP chemical composition information and related targets from databases. The drug-target and drug-target pathway networks were constructed using Cytoscape. Then the protein-protein interaction was analyzed using the STRING database. Gene Ontology biological functions and Kyoto Encyclopedia of Genes and Genomes pathways were performed by the Metascape database, and molecular docking validation of vital active ingredients and action targets of GFP was performed using AutoDock Vina software. The 51 active components in GFP are expected to influence CSA by controlling 279 target genes and 151 signaling pathways. Among them, 6 core components, such as quercetin, β-sitosterol, and baicalein, may regulate CSA by affecting 10 key target genes such as STAT3, IL-6, TP53, AKT1, and EGFR. In addition, they are involved in various critical signaling pathways such as apelin, calcium, advanced glycation end product-receptor for advanced glycation end product, and necroptosis. Molecular docking analysis confirms favorable binding interactions between the active components of GFP and the selected target proteins. The effects of GFP in treating CSA involve multiple components, targets, and pathways, offering a theoretical basis for its clinical use and enhancing our understanding of how it works.

Myocardial Ischemia: Differentiating between Epicardial Coronary Artery Atherosclerosis, Microvascular Dysfunction and Vasospasm in the Catheterization Laboratory

Ischemic heart disease is currently the most common cause of mortality and morbidity worldwide. Although myocardial ischemia is classically determined by epicardial coronary atherosclerosis, up to 40% of patients referred for coronary angiography have no obstructive coronary artery disease (CAD). Ischemia with non-obstructive coronary artery disease (INOCA) has typically been underestimated in the past because, until recently, its prognostic significance was not completely clear. This review aims to highlight differences and patterns in myocardial ischemia caused by epicardial obstructive CAD, coronary microvascular dysfunction (CMD) or vasomotor abnormalities and to elucidate the state of the art in correctly diagnosing these different patterns.

Case Report: Vasospastic angina presenting as phantom odor perception

Background

Vasospastic angina usually presents with intermittent episodes of chest pain. It can rarely be associated with the perception of phantom odors.

Case summary

A 69-year-old woman presented for evaluation of intermittent shortness of breath and chest pain. She reported that she often experienced an abnormal smell sensation just prior to the event. The patient had abnormal smell sensation and shortness of breath at the initiation of exercise stress echocardiography with transient electrocardiographic changes and new regional wall motion abnormalities. Subsequent invasive coronary angiography showed no obstructive epicardial coronary artery disease. The patient was started on calcium channel blocker therapy with resolution of symptoms.

Conclusion

Phantom odor perception has been rarely reported as an angina-equivalent symptom. Clinicians should have a high index of suspicion in patients presenting with atypical anginal symptoms.

A Systematic Approach to the Evaluation of the Coronary Microcirculation Using Bolus Thermodilution: CATH CMD

Coronary microvascular dysfunction (CMD) can cause myocardial ischemia in patients presenting with angina without obstructive coronary artery disease (ANOCA). Evaluating for CMD by using the thermodilution technique offers a widely accessible means of assessing microvascular resistance. Through this technique, 2 validated indices, namely coronary flow reserve and the index of microcirculatory resistance, can be computed, facilitating investigation of the coronary microcirculation. The index of microcirculatory resistance specifically estimates minimum achievable microvascular resistance within the coronary microcirculation. We aim to review the bolus thermodilution method, outlining the fundamental steps for conducting measurements and introducing an algorithmic approach (CATH CMD) to systematically evaluate the coronary microcirculation. Embracing a standardized approach, exemplified by the CATH CMD algorithm, will facilitate adoption of this technique and streamline the diagnosis of CMD.

Ischaemia with no obstructive coronary arteries: a review with focus on the Asian population

ABSTRACT

Ischaemia with no obstructive coronary arteries (INOCA) has been a diagnostic and therapeutic challenge for decades. Several studies have demonstrated that INOCA is associated with an increased risk of death, adverse cardiovascular events, poor quality of life and high healthcare cost. Although there is increasing recognition of this entity in the Western population, in the Asian population, INOCA remains elusive and its prevalence uncertain. Despite its prognostic significance, diagnosis of INOCA is often delayed. In this review, we identified the multiple barriers to its diagnosis and management, and proposed strategies to overcome them.

Inflammation and coronary microvascular disease: relationship, mechanism and treatment

Coronary microvascular disease (CMVD) is common in patients with cardiovascular risk factors and is linked to an elevated risk of adverse cardiovascular events. Although modern medicine has made significant strides in researching CMVD, we still lack a comprehensive understanding of its pathophysiological mechanisms due to its complex and somewhat cryptic etiology. This greatly impedes the clinical diagnosis and treatment of CMVD. The primary pathological mechanisms of CMVD are structural abnormalities and/or dysfunction of coronary microvascular endothelial cells. The development of CMVD may also involve a variety of inflammatory factors through the endothelial cell injury pathway. This paper first reviews the correlation between the inflammatory response and CMVD, then summarizes the possible mechanisms of inflammatory response in CMVD, and finally categorizes the drugs used to treat CMVD based on their effect on the inflammatory response. We hope that this paper draws attention to CMVD and provides novel ideas for potential therapeutic strategies based on the inflammatory response.

Relation of Vasoreactivity in the Left and Right Coronary Arteries During Acetylcholine Spasm Provocation Testing

The diagnosis of vasospastic angina (VSA) according to Japanese guidelines involves an initial intracoronary acetylcholine (ACh) provocation test in the left coronary artery (LCA) followed by testing in the right coronary artery (RCA). However, global variations in test protocols often lead to the omission of ACh provocation in the RCA, potentially resulting in the underdiagnosis of VSA. This study assessed the validity of the LCA-only ACh provocation approach for the VSA diagnosis and whether vasoreactivity in the LCA aids in determining further provocation in the RCA. A total of 273 patients who underwent sequential intracoronary ACh provocation testing in the LCA and RCA were included. Patients with a positive ACh provocation test in the LCA were excluded. Relations between vasoreactivity in the LCA and ACh test outcomes (positivity and adverse events) in the RCA were evaluated. In patients with negative ACh test results in the LCA, subsequent ACh testing was positive in the RCA in 23 of 273 (8.4%) patients. In patients with minimal LCA vasoconstriction (<25%), only 3.0% had a positive ACh test in the RCA, whereas the ACh test in the RCA was positive in 13.5% of those with LCA constriction of 25% to 90% (p = 0.002). No major adverse events occurred during ACh testing in the RCA. In conclusion, for the VSA diagnosis, the omission of ACh provocation in the RCA may be clinically acceptable, particularly when vasoconstriction induced by ACh injection was minimal in the LCA. Further studies are needed to define ACh provocation protocols worldwide.

Impact of renal denervation on patients with coronary microvascular dysfunction: study rationale and design

AIMS

Long-standing hypertension may cause an impairment in microvascular coronary circulation, which is involved in many different cardiac conditions. Renal sympathetic denervation (RDN) has been successfully proven as a valuable therapeutic choice for patients with resistant hypertension; moreover, the procedure looks promising in other settings, such as heart failure and atrial fibrillation, given its ability to downregulate the sympathetic nervous system, which is a recognized driver in these conditions as well as in microvascular dysfunction progression. The aim of this study is to explore the effect of RDN on coronary physiology in patients with ascertained coronary microvascular dysfunction and resistant hypertension.

METHODS

This is a multicenter, prospective, nonrandomized, open-label, interventional study. Consecutive patients with resistant hypertension, nonobstructive coronary artery disease (NOCAD) and documented microvascular dysfunction will be enrolled. Patients will undergo RDN by Spyral Symplicity 3 (Medtronic Inc, Minneapolis, Minnesota, USA) and reassessment of coronary microvascular function 6 months after the procedure. Primary endpoint will be the difference in the index of microcirculatory resistance.

CONCLUSION

The IMPRESSION study seeks to evaluate if there is any pleiotropic effect of the RDN procedure that results in modulation of microvascular function; if observed, this would be the first evidence showing RDN as a valuable therapy to revert hypertension-related microvascular dysfunction.

Profound Coronary Vasospasm Associated with Intraoperative Ketamine Administration: A Case Report

We report a case of a 62-year-old woman with a decade-long history of atypical chest pain resulting in a largely negative cardiac workup, who developed significant angiographically demonstrated coronary vasospasm thought to be due to a small dose of intravenous ketamine. In patients with a history of atypical chest pain despite a reassuring cardiac evaluation, providers should carefully consider medications that may precipitate coronary vasospasm and be prepared to treat it accordingly.

The Molecular Mechanisms and Therapeutic Targets of Atherosclerosis: From Basic Research to Interventional Cardiology

The goal of this Special Issue was to collect original pieces as well as state-of-the-art review articles from scientists and research groups with specific interests in atherosclerosis research [...].

Traditional Cardiovascular Risk Factors and Coronary Microvascular Dysfunction in Women and Men: A Single-Center Study

INTRODUCTION

Coronary microvascular dysfunction (CMD) is common in patients with and without obstructive epicardial coronary artery disease (CAD). Risk factors for the development of CMD have not been fully elucidated, and data regarding sex-associated differences in traditional cardiovascular risk factors for obstructive CAD in patients with CMD are lacking.

METHODS

In this single-center, prospective registry, we enrolled patients with nonobstructive CAD undergoing clinically indicated invasive assessment of coronary microvascular function between November 2019 and March 2023. Associations between coronary microvascular dysfunction, traditional cardiovascular risk factors, and sex were assessed using univariate and multivariate regression models.

RESULTS

Overall, 245 patients with nonobstructive CAD were included in the analysis (62.9% female; median age 68 (interquartile range: 59, 75). Microvascular dysfunction was diagnosed in 141 patients (57.5%). The prevalence of microvascular dysfunction was similar in women and men (59.0% vs. 57.0%; p = 0.77). No association was found between traditional risk factors for coronary atherosclerosis and CMD regardless of whether CMD was structural or functional. In women, but not in men, older age and the presence of previous ischemic heart disease were associated with lower coronary flow reserve (β = -0.29; p < 0.01 and β = -0.15; p = 0.05, respectively) and lower resistive reserve ratio (β = -0.28; p < 0.01 and β = -0.17; p = 0.04, respectively).

CONCLUSION

For the entire population, no association was found between coronary microvascular dysfunction and traditional risk factors for coronary atherosclerosis. In women only, older age and previous ischemic heart disease were associated with coronary microvascular dysfunction. Larger studies are needed to elucidate risk factors for CMD.

Impact of vessel volume on thermodilution measurements in patients with coronary microvascular dysfunction

BACKGROUND

Two invasive methods are available to estimate microvascular resistance: bolus and continuous thermodilution. Comparative studies have revealed a lack of concordance between measurements of microvascular resistance obtained through these techniques.

AIMS

This study aimed to examine the influence of vessel volume on bolus thermodilution measurements.

METHODS

We prospectively included patients with angina with non-obstructive coronary arteries (ANOCA) undergoing bolus and continuous thermodilution assessments. All patients underwent coronary CT angiography to extract vessel volume. Coronary microvascular dysfunction was defined as coronary flow reserve (CFR) < 2.0. Measurements of absolute microvascular resistance (in Woods units) and index of microvascular resistance (IMR) were compared before and after volumetric adjustment.

RESULTS

Overall, 94 patients with ANOCA were included in this study. The mean age was 64.7 ± 10.8 years, 48% were female, and 19% had diabetes. The prevalence of CMD was 16% based on bolus thermodilution, while continuous thermodilution yielded a prevalence of 27% (Cohen's Kappa 0.44, 95% CI 0.23-0.65). There was no correlation in microvascular resistance between techniques (r = 0.17, 95% CI -0.04 to 0.36, p = 0.104). The adjustment of IMR by vessel volume significantly increased the agreement with absolute microvascular resistance derived from continuous thermodilution (r = 0.48, 95% CI 0.31-0.63, p < 0.001).

CONCLUSIONS

In patients with ANOCA, invasive methods based on coronary thermodilution yielded conflicting results for the assessment of CMD. Adjusting IMR with vessel volume improved the agreement with continuous thermodilution for the assessment of microvascular resistance. These findings strongly suggest the importance of considering vessel volume when interpreting bolus thermodilution assessment.

Comparison of bolus versus continuous thermodilution derived indices of microvascular dysfunction in revascularized coronary syndromes

Background

The assessment of coronary microvascular dysfunction (CMD) using invasive methods is a field of growing interest, however the preferred method remains debated. Bolus and continuous thermodilution are commonly used methods, but weak agreement has been observed in patients with angina with non-obstructive coronary arteries (ANOCA). This study examined their agreement in revascularized acute coronary syndromes (ACS) and chronic coronary syndromes (CCS) patients.

Objective

To compare bolus thermodilution and continuous thermodilution indices of CMD in revascularized ACS and CCS patients and assess their diagnostic agreement at pre-defined cut-off points.

Methods

Patients from two centers underwent paired bolus and continuous thermodilution assessments after revascularization. CMD indices were compared between the two methods and their agreements at binary cut-off points were assessed.

Results

Ninety-six patients and 116 vessels were included. The mean age was 64 ± 11 years, and 20 (21 %) were female. Overall, weak correlations were observed between the Index of Microcirculatory Resistance (IMR) and continuous thermodilution microvascular resistance (Rµ) (rho = 0.30p = 0.001). The median coronary flow reserve (CFR) from continuous thermodilution (CFRcont) and bolus thermodilution (CFRbolus) were 2.19 (1.76-2.67) and 2.55 (1.50-3.58), respectively (p < 0.001). Weak correlation and agreement were observed between CFRcont and CFRbolus (rho = 0.37, p < 0.001, ICC 0.228 [0.055-0.389]). When assessed at CFR cut-off values of 2.0 and 2.5, the methods disagreed in 41 (35 %) and 45 (39 %) of cases, respectively.

Conclusions

There is a significant difference and weak agreement between bolus and continuous thermodilution-derived indices, which must be considered when diagnosing CMD in ACS and CCS patients.

Compositional plaque progression in women and men with non-obstructive coronary artery disease

Background

In coronary artery disease (CAD), plaque progression and plaque composition are associated with cardiovascular risk. Whether compositional plaque progression in non-obstructive CAD differs between women and men is less studied.

Methods

We included 31 patients (42% women) with chronic non-obstructive CAD from the Norwegian Registry of Invasive Cardiology, undergoing serial coronary computed tomography angiography (CCTA) on clinical indication (median inter-scan interval 1.8 [1.5-2.2] years). We performed quantitative and qualitative plaque analysis of all coronary artery segments.

Results

Women were older compared to men (65 ± 8 years vs. 55 ± 12 years, p = 0.019), while there was no difference in the prevalence of hypertension, diabetes, smoking or statin treatment between groups. At baseline, women had a higher total plaque burden, more calcified plaques, and less fibro-fatty and necrotic core plaques compared to men (all p < 0.05). During follow-up, men showed faster progression of fibro-fatty plaques (4.0 ± 5.4 % per year vs. -0.6 ± 3.1 % per year, p = 0.019) and a greater reduction of fibrous plaques (-7.3 ± 6.1 % per year vs. 2.1 ± 7.2 % per year, p = 0.003) compared to women even after age adjustment. At follow-up, total plaque burden remained higher in women compared to men (24.9 ± 3.3 % vs. 21.1 ± 2.6 %, p = 0.001), while men had an increase in fibro-fatty (21.2 ± 9.3 % vs. 28.6 ± 9.8 %, p = 0.004) and necrotic core plaques (5.6 ± 3.6 % vs. 10.8 ± 7.2 %, p = 0.006), and a decrease in fibrous plaques (69.0 ± 11.9 % vs. 54.7 ± 13.7 %, p < 0.001). Women's plaque composition remained unaltered.

Conclusion

In non-obstructive CAD, serial CCTA demonstrated a higher total plaque burden and a stable plaque composition in women, while men had a faster progression of unstable low-attenuating fibro-fatty plaques.Clinical trial registration: ClinicalTrials.gov: Identifier NCT04009421.

Takayasu's Arteritis: A Special Case Report and Review of the Literature

Background: Takayasu's arteritis is a rare type of vasculitis with severe complications like stroke, ischemic heart disease, pulmonary hypertension, secondary hypertension, and aneurysms. Diagnosis is achieved using clinical and angiographic criteria. Treatment is medical and surgical, but unfortunately, the outcome is limited. Case presentation: A 34-year-old Caucasian woman had an ischemic stroke (2009). She was diagnosed with Takayasu's arteritis and received treatment with methotrexate, prednisolone, and antiplatelet agents, with a mild improvement in clinical state. After 6 years (2015), she experienced an ascending aorta aneurysm, pulmonary hypertension, and mild aortic regurgitation. Surgical treatment solved both the ascending aorta aneurysm and left carotid artery stenosis (ultrasound in 2009 and computed tomography angiogram in 2014). Morphopathology revealed a typical case of Takayasu's arteritis. Tumor necrosis factor inhibitors (TNF inhibitors) were prescribed with methotrexate. At 48 years old (2023), she developed coronary heart disease (angina, electrocardiogram); echocardiography revealed severe pulmonary hypertension, and angiography revealed normal coronary arteries, abdominal aorta pseudoaneurysm, and arterial-venous fistula originating in the right coronary artery with drainage in the medium pulmonary artery. The patient refused surgical/interventional treatment. She again received TNF inhibitors, methotrexate, antiplatelet agents, and statins. Conclusions: This case report presented a severe form of Takayasu's arteritis. Our patient had multiple arterial complications, as previously mentioned. She received immunosuppressive treatment, medication targeted to coronary heart disease, and surgical therapy.