Culprit plaque characteristics in women vs men with a first ST-segment elevation myocardial infarction: In vivo optical coherence tomography insights

Sex-related differences in coronary and carotid vessel geometry, plaque composition and shear stress obtained from imaging

Atherosclerosis manifests itself differently in men and women with respect to plaque initiation, progression and plaque composition. The observed delay in plaque progression in women is thought to be related to the hormonal status of women. Also features associated with the vulnerability of plaques to rupture seem to be less frequently present in women compared to men. Current invasive and non-invasive imaging modalities allow for visualization of plaque size, composition and high risk vulnerable plaque features. Moreover, image based modeling gives access to local shear stress and shear stress-related plaque growth. In this review, current knowledge on sex-related differences in plaque size, composition, high risk plaque features and shear stress related plaque growth in carotid and coronary arteries obtained from imaging are summarized.

Coronary atherosclerotic plaque phenotype and physiopathologic mechanisms: Is there an influence of sex? Insights from intracoronary imaging

Coronary artery disease (CAD) is the leading cause of disability and death in both women and men; considerable differences in clinical presentation, natural history and prognosis are reported between sexes. Different pathophysiological mechanisms play a major role, including sex-related and gender-related features or a combination of both. Reports from intracoronary imaging studies pointed towards morphological plaque features, which seemed to differ between men and women, albeit results reported so far were not conclusive. The purpose of this review is to shed light on differences in the pathophysiology underlying CAD in women vs men including the description of coronary plaque phenotype and mechanisms of plaque instability, as assessed by intracoronary imaging. We will also discuss potential clinical implications with the aim to move towards a sex and gender-based personalized approach in CAD patients.

Percutaneous Coronary Interventions in Women

PURPOSEOF REVIEW

Cardiovascular disease is the leading cause of morbidity and mortality among women globally. Numerous studies show ongoing disparities in diagnosis, management, and outcomes of ischemic heart disease in women compared to men. We aim to review the factors contributing to sex-based differential outcomes of percutaneous coronary interventions in women.

RECENT FINDINGS

Hormonal influence on coronary arteries and progression of atherosclerosis in women results in distinct coronary plaque characteristics and unique pathological process such as spontaneous coronary artery dissection and myocardial infarction with non-obstructive coronary arteries. During the presentation of acute coronary syndromes, women are older and have higher burden of comorbidities, with higher short- and long-term mortality. Awareness of differences in vascular biology and unique risk factors for cardiovascular disease in women is essential for sustained improvement in cardiovascular mortality. Better representation of women in trials is crucial to address the gaps in knowledge and allow for individualized treatment approaches in women.

Utility of optical coherence tomography in acute coronary syndromes

Studies utilizing intravascular imaging have replicated the findings of histopathological studies, identifying the most common substrates for acute coronary syndromes (ACS) as plaque rupture, erosion, and calcified nodule, with spontaneous coronary artery dissection, coronary artery spasm, and coronary embolism constituting the less common etiologies. The purpose of this review is to summarize the data from clinical studies that have used high-resolution intravascular optical coherence tomography (OCT) to assess culprit plaque morphology in ACS. In addition, we discuss the utility of intravascular OCT for effective treatment of patients presenting with ACS, including the possibility of culprit lesion-based treatment by percutaneous coronary intervention.

Sex Differences in Culprit Plaque Characteristics Among Different Age Groups in Patients With Acute Coronary Syndromes

BACKGROUND

Despite the significant decline in cardiovascular mortality in women over the past several decades, sex differences in the underlying pathology of acute coronary syndromes remain poorly understood. Previous postmortem studies have demonstrated sex differences in coronary plaque morphology with a higher prevalence of plaque erosion in young women and more plaque rupture in older women after menopause, whereas men showed no increase in prevalence of plaque rupture with age. However, in vivo data are limited.

METHODS

This study included patients who presented with acute coronary syndrome and underwent preintervention optical coherence tomography imaging of the culprit lesion. The culprit plaque was categorized as plaque rupture, plaque erosion or culprit plaque with calcification, and stratified by age. Features of plaque vulnerability at culprit lesion were also analyzed.

RESULTS

In 1368 patients (women=286), women and men had a similar distribution of culprit plaque morphology (plaque rupture versus plaque erosion). However, significant sex differences were found in the underlying mechanisms of acute coronary syndrome among different age groups: women showed a significant ascending trend with age in plaque rupture (P<0.001) and the features of plaque vulnerability such as lipid plaque (P<0.001), thin-cap fibroatheroma (P=0.005), and microstructures including macrophages, cholesterol crystals, and calcification (P=0.026). No trend was observed in men.

CONCLUSIONS

Age related sex differences in culprit plaque morphology and vulnerability were identified in patients with acute coronary syndrome: prevalence of plaque rupture and vulnerability increased with age in women but not in men.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT01110538 and NCT03479723.

Near-infrared spectroscopy predicts events in men and women: Results from the Lipid Rich Plaque study

Background

The Lipid Rich Plaque (LRP) study demonstrated that near-infrared spectroscopy imaging of non-obstructive lesions identified patients and segments at higher risk for subsequent non-culprit major adverse cardiac events (NC-MACE). Whether this is true for both men and women is not known. In this post hoc analysis of the LRP study, we sought to investigate whether the maximum 4-mm Lipid Core Burden Index (maxLCBI_4mm) was of similar predictive value in men and women for NC-MACE.

Methods

Patients with an evaluable maxLCBI_4mm were stratified on the basis of sex at birth. A Cox proportional-hazards model was used to assess the predictive value of maxLCBI_4mm on future NC-MACE at the patient and plaque levels. The primary endpoint was cumulative incidence of NC-MACE at 24 months.

Results

Among 1271 patients, 388 (30.5%) were women. Women were older and had a higher cardiovascular risk profile. Cumulative incidence of NC-MACE at 24 months was 10.3% for women and 7.6% for men (log-rank p = 0.11). When comparing maxLCBI_4mm > 400 to maxLCBI_4mm ≤ 400, the hazard ratio (HR) for future NC-MACE was not significantly different between sexes: 2.10 (95% confidence interval [CI]: 1.28–3.44; p = 0.003) for men and 2.24 (95% CI: 1.18–4.28; p = 0.014) for women (p = 0.87). At the plaque level, the HR comparing maxLCBI_4mm > 400 to maxLCBI_4mm ≤ 400 was 3.49 (95% CI: 1.60–7.60, p = 0.002) for men and 4.79 (95% CI: 2.02–11.38, p < 0.001) for women, which was not significantly different (p = 0.57).

Conclusions

The maxLCBI_4mm was of similar predictive value for NC-MACE within 24 months in men and women.

Nuclear Cardiology in Women and Underrepresented Minority Populations

PURPOSE OF REVIEW

To outline sex-specific features of coronary artery disease (CAD) that should be considered in the assessment of women, including those from ethnic minority populations with suspected stable ischemic heart disease (IHD). Second, to determine the latest nuclear imaging tools available to assess microvascular CAD.

RECENT FINDINGS

Latest studies indicate that women are more likely to have ischemia with no obstructive coronary arteries (INOCA) and paradoxically have worse outcomes. Therefore, the evaluation of women with suspected IHD should include assessing microvascular and epicardial coronary circulation. The prevalence of CAD is increasing in younger women due to the increased cardiovascular disease (CVD) risk burden. CAD is often underrecognized in these patients. There is increasing recognition that INOCA is not benign and should be accurately diagnosed and managed. Nuclear imaging assesses the full spectrum of CAD from microvascular CAD to multivessel obstructive epicardial CAD. Further research on myocardial blood flow (MBF) assessment with PET MPI is needed.

Underrepresentation of women in cardiovascular trials- it is time to shatter this glass ceiling

Cardiovascular disease (CVD) is the leading cause of death in women, with underrepresented minority (URM) women experiencing the highest mortality rate. For decades, there has been an underrepresentation of women in CVD trials. Although more recent studies have increased the number of women enrolled in these trials, systematic reviews have demonstrated that this enrollment is still low. The National Institute of Health along with other agencies have boosted their efforts to increase enrollment of women and URM populations in CVD trials. Despite these efforts, there still remains a gap. This paper reviews the magnitude, implications and causes of the underrepresentation of women in CVD trials. A proposed multifaceted approach to solving this issue is also outlined in this commentary. Hopefully, implementation of these proposed solutions may facilitate the increase of women, including URM women, enrolled in CVD trials. It is anticipated that this will improve CVD outcomes in these patients.

Gender-based in vivo comparison of culprit plaque characteristics and plaque microstructures using optical coherence tomography in acute coronary syndrome

Introduction: Women perform worse after acute coronary syndrome (ACS) than men. The reason for these differences is unclear. The aim was to ascertain gender differences in the culprit plaque characteristics in ACS.

Methods: Patients with ACS undergoing percutaneous coronary intervention for the culprit vessel underwent optical coherence tomography (OCT) imaging. Culprit plaque was identified as lipid rich,fibrous, and calcific plaque. Mechanisms underlying ACS are classified as plaque rupture, erosion,or calcified nodule. A lipid rich plaque along with thin-cap fibroatheroma (TCFA) was a vulnerable plaque. Plaque microstructures including cholesterol crystals, macrophages, and microvessels were noted.

Results: A total of 52 patients were enrolled (men=29 and women=23). Baseline demographic features were similar in both the groups except men largely were current smokers (P <0.001). Plaque morphology,men vs. women: lipid rich 88.0% vs. 90.5%; fibrous 4% vs 0%; calcific 8.0% vs. 9.5% (P = 0.64). Of the ACS mechanisms in males versus females; plaque rupture (76.9 % vs. 50 %), plaque erosion (15.4 % vs.40 %) and calcified nodule (7.7 % vs. 10 %) was noted (P = 0.139). Fibrous cap thickness was (50.19 ±11.17 vs. 49.00 ± 10.71 mm, P = 0.71) and thin-cap fibroatheroma (96.2% vs. 95.0%, P = 1.0) in men and women respectively. Likewise no significant difference in presence of macrophages (42.3 % vs. 30%, P = 0.76), microvessels (73.1% vs. 60 %, P = 0.52) and cholesterol crystals (92.3% vs. 80%, P = 0.38).

Conclusion: No significant gender-based in-vivo differences could be discerned in ACS patients’ culprit plaques morphology, characteristics, and underlying mechanisms.

The evolving role of coronary computed tomography in understanding sex differences in coronary atherosclerosis

Our understanding of sex differences in subclinical atherosclerosis and plaque composition and characteristics have greatly improved with the use of coronary computed tomography (CCTA) over the past years. CCTA has emerged as an important frontline diagnostic test for women, especially as we continue to understand the impact of non-obstructive atherosclerosis as well as diffuse, high risk plaque as precursors of acute cardiac events in women. Based on its ability to identify complex plaque morphology such as low attenuation plaque, high risk non calcified plaque, positive remodeling, fibrous cap, CCTA can be used to assess plaque characteristics. CCTA can avoid false positive of other imaging studies, if included earlier in assessment of ischemic symptoms. In the contemporary clinical setting, CCTA will prove useful in further understanding and managing cardiovascular disease in women and those without traditional obstructive coronary disease.

Plaque characteristics in patients with ST-segment elevation myocardial infarction and early spontaneous reperfusion

BACKGROUND

Early spontaneous reperfusion (ESR) is not an uncommon phenomenon in clinical settings.

AIMS

The aim of this study was to detect potential mechanisms of ESR in patients with STEMI.

METHODS

This prospective study enrolled a total of 241 consecutive patients with STEMI undergoing optical coherence tomography (OCT) from July 2016 to August 2019. Forty-five patients (18.7%) met angiographic ESR criteria (TIMI 3 flow on the initial angiogram). Among those without ESR (TIMI 0 flow on initial angiogram), 45 patients were assigned to the control group according to propensity score matching with the ESR group.

RESULTS

Although the baseline characteristics of the groups were comparable, non-ruptured plaque (62.2% vs 35.6%) predominated and plaque rupture (37.8% vs 64.4%) was less common in the ESR group (p=0.011). Red thrombus (44.4% vs 77.8%) was also less common in the ESR group (p=0.001). Lastly, compared to the control group, the ESR group underwent fewer emergent stent placements (68.9% vs 91.1%, p=0.008).

CONCLUSIONS

Relief of coronary occlusion induced by a non-ruptured plaque may contribute to ESR in patients with STEMI.

Atherothrombosis in Acute Coronary Syndromes-From Mechanistic Insights to Targeted Therapies

The atherothrombotic substrates for acute coronary syndromes (ACS) consist of plaque ruptures, erosions and calcified nodules, while the non-atherothrombotic etiologies, such as spontaneous coronary artery dissection, coronary artery spasm and coronary embolism are the rarer causes of ACS. The purpose of this comprehensive review is to (1) summarize the histopathologic insights into the atherothrombotic plaque subtypes in acute ACS from postmortem studies; (2) provide a brief overview of atherogenesis, while mainly focusing on the events that lead to plaque destabilization and disruption; (3) summarize mechanistic data from clinical studies that have used intravascular imaging, including high-resolution optical coherence tomography, to assess culprit plaque morphology and its underlying pathobiology, especially the newly described role of innate and adaptive immunity in ACS secondary to plaque erosion; (4) discuss the utility of intravascular imaging for effective treatment of patients presenting with ACS by percutaneous coronary intervention; and (5) discuss the opportunities that these mechanistic and imaging insights may provide for more individualized treatment of patients with ACS.

Age- and Gender-Related Differences in Coronary Lesion Plaque Composition on Optical Coherence Tomography

BACKGROUND

The pathophysiology and chronological course of atherosclerosis seems to be different between men and women due to biological differences, and age and gender differences in plaque composition of coronary lesions remain to be elucidated.Methods and Results:A total of 860 consecutive patients with a median age of 69 years (IQR, 60-78 years) who underwent optical coherence tomography (OCT) of culprit lesions was included. The composition of culprit plaque on OCT was compared between female (n=171) and male (n=689) subjects in younger (<70 years old) and elderly (≥70 years old) patients. In elderly patients, the prevalence of thin-cap fibroatheroma (TCFA) was significantly higher in women than in men (30.6 vs. 15.2%, P<0.001). In younger patients, the prevalence of large calcification was significantly higher in women than in men (60.0 vs. 32.8%, P<0.001). The prevalence of other vulnerable plaque characteristics (i.e., macrophages, microchannels, and spotty calcification), was similar between women and men. Elderly women had a significantly higher prevalence of TCFA (OR, 2.13; 95% CI: 1.33-3.44, P=0.002) than other patients.

CONCLUSIONS

Women had a higher prevalence of TCFA and of large calcification than men in patients ≥70 and <70 years old, respectively. This may facilitate the understanding of gender differences in the pathogenesis of coronary atherosclerosis, and the tailoring of therapy and of prevention according to age and gender.

[Association of Strategy of Direct Stenting of Infarct-Related Artery with Reduction of Mortality in Woman with ST-Elevation Myocardial Infarction]

Aim of this study was to evaluate the impact of direct stenting (DS) strategy on the results of treatment of female patients with STelevation myocardial infarction (STEMI) undergoing percutaneous coronary interventions (PCIs).

MATERIALS AND METHODS

Among 1297 patients with STEMI admitted to the coronary care unit and subjected to PCIs from 2006 to 2015 there were 330 women (25.4 %). Data from 161 women (48.8 %) who underwent DS were compared with those from 169 women who underwent indirect stenting (IS). Among patients of IS group in 148 (87.6 %) stenting was performed after predilation, in 7 (4.1 %) after manual thrombus aspiration, and in 14 (8.3 %) after combination of predilation and thrombus aspiration.

RESULTS

The rate of angiographic success was higher in the DS group (97.5 vs. 87.6 %, р&lt;0.001). Rates of deaths (4.3 vs. 11.8 %; p=0.013), major adverse cardiac events (MACE)(4.3 vs. 13 %; p=0.005), and no-reflow (1.9 % vs. 11.2 %; p=0.013) were significantly lower in the DS group. There were no differences in rates of recurrent myocardial infarction and access site complications. Following propensity score matching, each group contained 78 patients. Rates of MACE (2.6 vs. 14.1 %; p=0.009) and deaths (2.6 vs. 12.8 %; p=0.016) remained significantly lower in the DS group. After multivariate adjustment, DS strategy was independently associated with lower mortality (odds ratio [OR] 0.29; 95 % confidence interval [CI] 0.09-0.97; p=0.04) and MACE (OR=0.28; 95 %CI 0.09-0.087; p=0.03).

CONCLUSION

DS strategy in STEMI female patients turned out to be safe and effective technique.

Gender differences in plaque characteristics of nonculprit lesions in patients with coronary artery disease

BACKGROUND

Although numerous reports suggest sex-related differences in atherosclerosis, limited data describing gender-associated differences in plaque morphology and composition are currently available. The aim of the present study was to compare coronary nonculprit plaque characteristics in women and men with coronary artery disease (CAD) by optical coherence tomography (OCT).

METHODS

This was a retrospective study. A total of 187 nonculprit plaques were identified in 103 patients with CAD who underwent OCT imaging of all 3 coronary arteries. These patients included 77 (74.8%) men and 26 (25.2%) women.

RESULTS

Female patients were significantly older than males (mean age, 70.8 ± 7.3 vs 60.8 ± 9.8 years; P < 0.001) and less likely to be current smokers (P = 0.007). OCT analysis included the presence of lipid-rich plaque, maximum lipid arc, lipid-core length, lipid index (LI), fibrous cap thickness, and the incidence of thin-cap fibroatheroma (TCFA). Nonculprit plaques in men exhibited greater lipid-core length and LI compared with those of women (9.4 ± 4.5 vs. 7.3 ± 4.3 mm, P = 0.024; 1615.1 ± 893.8 vs. 1237.8 ± 859.8, P = 0.035, respectively). In the univariate linear regression model, sex and current smoker were all associated with a larger LI, whereas only use of statin was independent risk factor for a larger LI in multivariate analysis.

CONCLUSIONS

Coronary nonculprit plaques in male patients with CAD contain larger lipid cores than those of female patients.

Correlation between pre-procedural plaque morphology and patterns of in-stent neointimal hyperplasia at 1-year follow-up in patients treated with new-generation drug-eluting stents: An optical coherence tomography based analysis

INSTRUCTION

Several factors affect the in-stent intimal healing process after drug-eluting stents (DESs) implantation. We hope to investigate the influence of plaque characteristics on subsequent heterogeneous neointimal hyperplasia (NIH) using optical coherence tomography (OCT).

METHODS

The study population consisted 217 patients with single-vessel de novo lesions who underwent both pre-procedural OCT scan and 12-month follow-up OCT examination. NIH is defined as at least five consecutive cross-sectional images with no less than 100µm neointimal thickness. According to OCT follow-up, patients were divided into three groups: neointima-covered group, homogeneous, and heterogeneous NIH group.

RESULTS

102 patients were categorized in neointima-covered group, 91 and 24 patients in homogeneous and heterogeneous group, respectively. Time interval between OCT scans was similar (P = 0.55). No significant differences in the patients' age, gender, comorbidities, laboratory findings, procedural, and lesion-related findings were found among these three groups. Heterogeneous group tended to have more subjects presented as acute coronary syndrome (ACS) (P = 0.04) and mean macrophage grade was higher in this group (P = 0.01). While no statistically significant difference concerning mean intimal thickness (P = 0.21) or neointimal burden (P = 0.73) was found between homogeneous and heterogeneous group. Multivariate logistic regression analysis showed that mean macrophage grade (OR: 2.26, 95%CI: 1.12 to 4.53, P = 0.02) and initial clinical presentation of ACS (OR: 2.81, 95%CI: 1.03 to 7.72, P = 0.04) were significant independent risk factors for heterogeneous NIH.

CONCLUSION

Mean macrophage grade measured by OCT as a semi-quantitative morphological risk factor, as well as clinical presentation of ACS, was associated with in-stent neointimal heterogeneity after DES implantation.

Culprit plaque characteristics in women vs men with a first ST-segment elevation myocardial infarction: In vivo optical coherence tomography insights

BACKGROUND

It is unclear whether more severe coronary atherosclerosis is a prerequisite to an initial acute coronary event in women vs men.

HYPOTHESIS

Women may have more severe coronary atherosclerosis than men in patients with acute coronary event.

METHODS

We used intravascular optical coherence tomography (OCT) to evaluate gender differences in culprit-plaque morphology in patients with a first ST-segment elevation myocardial infarction (STEMI).We retrospectively enrolled 211 consecutive patients who experienced a first STEMI and underwent an OCT examination of their infarct-related artery before primary percutaneous coronary intervention.

RESULTS

Of the 211 patients enrolled, 162 (76.7%) were men and 49 (23.2%) were women. The women were significantly older than the men (mean age, 60.2 ± 8.2 vs 55.7 ± 11.2 years; P = 0.01) and less likely to be current smokers (P = 0.02). Moreover, the delay from symptom onset to reperfusion was longer in women than in men (7.6 ± 6.1 vs 5.5 ± 4.4 hours; P = 0.01). The OCT data indicated that there were no gender differences in culprit-plaque morphology, including lipid length, lipid arc, minimum fibrous cap thickness, or minimum lumen area. Additionally, no gender differences were found in the prevalence of plaque rupture, thin-cap fibroatheroma, residual thrombus, microvessels, macrophages, cholesterol crystals, or calcification.

CONCLUSIONS

Among patients presenting with a first STEMI, there were no differences in culprit plaque features between women and men.