Molecular and Pathophysiological Mechanisms Leading to Ischemic Heart Disease in Patients with Diabetes Mellitus

Coronary atherosclerosis in patients with diabetes mellitus is the most significant pathophysiological mechanism responsible for ischemic heart disease. Atherosclerosis in diabetes is premature, more diffuse, and more progressive, and it affects more coronary blood vessels compared to non-diabetics. Atherosclerosis begins with endothelial dysfunction, continues with the formation of fatty streaks in the intima of coronary arteries, and ends with the appearance of an atherosclerotic plaque that expands centrifugally and remodels the coronary artery. If the atherosclerotic plaque is injured, a thrombus forms at the site of the damage, which can lead to vessel occlusion and potentially fatal consequences. Diabetes mellitus and atherosclerosis are connected through several pathological pathways. Among the most significant factors that lead to atherosclerosis in diabetics are hyperglycemia, insulin resistance, oxidative stress, dyslipidemia, and chronic inflammation. Chronic inflammation is currently considered one of the most important factors in the development of atherosclerosis. However, to date, no adequate anti-inflammatory therapeutic measures have been found to prevent the progression of the atherosclerotic process, and they remain a subject of ongoing research. In this review, we summarize the most significant pathophysiological mechanisms that link atherosclerosis and diabetes mellitus.

Suboptimal Control of Small Dense Low-Density Lipoprotein Cholesterol Is Associated With Coronary Plaque Progression: An Intravascular Ultrasound Study

BACKGROUND

Plaque progression (PP) is critical between subclinical atherosclerosis and plaque rupture. Small dense low-density lipoprotein cholesterol (sdLDL-C) is considered as the most atherogenic lipoprotein. This study aims to investigate the relationship between sdLDL-C level and PP in patients with stable coronary artery disease.

METHODS

We conducted a retrospective analysis of 146 lesions in 86 patients by repeat intravascular ultrasound examinations from January 2020 to May 2023. PP was determined by increases in percent atheroma volume, defined as the atheroma volume in proportion to the volume occupied by the entire vascular wall, ≥5% during follow-up. Time-averaged values were calculated for all cardiometabolic parameters including sdLDL-C. Multivariate logistic regression analysis was performed to interrogate the association between time-averaged sdLDL-C and PP.

RESULTS

During a median follow-up of 12.6 months, PP was found in 65 lesions (44.5%), and mean changes in percent atheroma volume were 4.1%±10.2%. A positive correlation was observed between time-averaged sdLDL-C and changes in total atheroma volume (Pearson r=0.29, P=0.006), especially in diabetic patients (Pearson r=0.58, P<0.001). After multivariate adjustment, every 0.1-mmol/L increase in time-averaged sdLDL-C conferred a 1.2-fold increased risk of PP.

CONCLUSIONS

Our findings suggest that sdLDL-C is an independent risk factor of PP in patients with coronary artery disease. Intensive control of sdLDL-C along with other risk factors should be considered to mitigate PP and improve cardiovascular outcomes.

Lesion-Level Effects of LDL-C-Lowering Therapy in Patients With Acute Myocardial Infarction: A Post Hoc Analysis of the PACMAN-AMI Trial

Importance

Previous studies investigated atherosclerotic changes induced by lipid-lowering therapy in extensive coronary segments irrespective of baseline disease burden (a vessel-level approach).

Objective

To investigate the effects of lipid-lowering therapy on coronary lesions with advanced atherosclerotic plaque features and presumably higher risk for future events.

Design, Setting, and Participants

The PACMAN-AMI randomized clinical trial (enrollment: May 2017 to October 2020; final follow-up: October 2021) randomized patients with acute myocardial infarction to receive alirocumab or placebo in addition to high-intensity statin therapy. In this post hoc lesion-level analysis, nonculprit lesions were identified as segments with plaque burden 40% or greater defined by intravascular ultrasound (IVUS). IVUS, near-infrared spectroscopy, and optical coherence tomography images at baseline and the 52-week follow-up were manually matched by readers blinded to treatment allocation. Data for this study were analyzed from October 2022 to November 2023.

Interventions

Alirocumab or placebo in addition to high-intensity statin therapy.

Main Outcomes and Measures

Lesion-level imaging outcome measures, including high-risk plaque characteristics and phenotypes.

Results

Of the 245 patients in whom lesions were found, 118 were in the alirocumab group (mean [SD] age, 58.2 [10.0] years; 101 [85.6%] male and 17 [14.4%] female) and 127 in the placebo group (mean [SD] age, 57.7 [8.8] years; 104 [81.9%] male and 23 [18.1%] female). Overall, 591 lesions were included: 287 lesions (118 patients, 214 vessels) in the alirocumab group and 304 lesions (127 patients, 239 vessels) in the placebo group. Lesion-level mean change in percent atheroma volume (PAV) was -4.86% with alirocumab vs -2.78% with placebo (difference, -2.02; 95% CI, -3.00 to -1.05; P < .001). At the minimum lumen area (MLA) site, mean change in PAV was -10.14% with alirocumab vs -6.70% with placebo (difference, -3.36; 95% CI, -4.98 to -1.75; P < .001). MLA increased by 0.15 mm2 with alirocumab and decreased by 0.07 mm2 with placebo (difference, 0.21; 95% CI, 0.01 to 0.41; P = .04). Among 122 lipid-rich lesions, 34 of 55 (61.8%) in the alirocumab arm and 27 of 67 (41.8%) in the placebo arm showed a less lipid-rich plaque phenotype at follow-up (P = .03). Among 63 lesions with thin-cap fibroatheroma at baseline, 8 of 26 (30.8%) in the alirocumab arm and 3 of 37 (8.1%) in the placebo arm showed a fibrous/fibrocalcific plaque phenotype at follow-up (P = .02).

Conclusions and Relevance

At the lesion level, very intensive lipid-lowering therapy induced substantially greater PAV regression than described in previous vessel-level analyses. Compared with statin therapy alone, alirocumab treatment was associated with greater enlargement of the lesion MLA and more frequent transition of presumably high-risk plaque phenotypes into more stable, less lipid-rich plaque phenotypes.

Trial Registration

ClinicalTrials.gov Identifier: NCT03067844.

Plaque Stabilization and Regression, from Mechanisms to Surveillance and Clinical Strategies

With advances in therapies to reduce cardiovascular events and improvements in coronary imaging, an increasing number of clinical trials have demonstrated that treatments to reduce cardiovascular events in coronary artery disease are associated with favorable effects on atherosclerotic plaque size and characteristics. It has been observed that various drugs may induce plaque regression and enhance plaque stability after plaque formation. Numerous clinical trials have been conducted to verify the occurrence of plaque stabilization and regression and their beneficial effects on cardiovascular events. Using invasive imaging techniques such as intravascular ultrasound (IVUS) and optical coherence tomography (OCT), researchers have been able to gather evidence supporting the existence of coronary plaque stabilization and regression. In this review, we explore the possible mechanisms of plaque stabilization and regression, summarize the imaging features of plaque stabilization and regression, and assemble the evidence from clinical studies that have used different features as observational endpoints.

Comparative Effectiveness and Safety of Atorvastatin Versus Rosuvastatin : A Multi-database Cohort Study

BACKGROUND

Rosuvastatin and atorvastatin are the most widely prescribed moderate- to high-intensity statins. However, evidence on their efficacy and safety during actual use is limited.

OBJECTIVE

To compare the real-world effectiveness and safety of rosuvastatin and atorvastatin.

DESIGN

Active comparator cohort study using target trial emulation.

SETTING

The China Renal Data System (CRDS) and UK Biobank (UKB) databases.

PARTICIPANTS

Adults newly prescribed rosuvastatin or atorvastatin.

MEASUREMENTS

The primary outcome was all-cause mortality. Cox proportional hazards regressions were used after 1:1 multilevel propensity score matching.

RESULTS

Among the 285 680 eligible participants in both databases, 6-year all-cause mortality was lower for rosuvastatin than for atorvastatin (2.57 vs. 2.83 per 100 person-years in the CRDS database and 0.66 vs. 0.90 per 100 person-years in the UKB database), with differences in cumulative incidence of -1.03% (95% CI, -1.44% to -0.46%) in the CRDS database and -1.38% (CI, -2.50% to -0.21%) in the UKB database. For secondary outcomes in both databases, rosuvastatin conferred lower risks for major adverse cardiovascular events and major adverse liver outcomes. In the UKB database, the risk for development of type 2 diabetes mellitus was higher with rosuvastatin, and the 2 medications carried similar risks for development of chronic kidney disease and other statin-related adverse effects.

LIMITATION

Possible residual confounding.

CONCLUSION

This study found differences in risks for some important outcomes associated with rosuvastatin and atorvastatin. The differences were relatively small, and many did not meet traditional standards for statistical significance. Further research is needed to understand whether these findings can be used with confidence in clinical practice.

PRIMARY FUNDING SOURCE

National Key R&D Program of China and National Natural Science Foundation of China.

Interplay of Age and Risk Factor Control Upon Coronary Atheroma Progression

BACKGROUND & AIM

The extent and composition of coronary plaque, and its progression differ with patients' age. The interplay of patient's age with respect to risk factor control, upon atheroma progression has not been evaluated. We tested the hypothesis that risk factor control modulates the association between age and coronary atheroma progression.

METHOD

We performed a posthoc pooled analysis of data from 10 prospective, randomised trials involving serial coronary intravascular ultrasonography (IVUS) (n=5,823). The percent atheroma volume (PAV) was calculated as the proportion of the entire vessel wall occupied by atherosclerotic plaque.

RESULTS

Mean overall age was 58±9 years (28% women). In a fully adjusted multivariable analysis (following adjustment of sex, body mass index, systolic blood pressure [SBP], smoking, high-density lipoprotein and low-density lipoprotein [LDL]-cholesterol, triglyceride levels, peripheral vascular disease, diabetes mellitus, trial, region, and baseline PAV), an increase in age by one standard deviation was linked with PAV progression (β-estimate 0.097; 95% confidence interval 0.048-0.15; p<0.001). In patients with good risk factor control (LDL-cholesterol <1.8 mmol/L and SBP <130 mmHg), increasing age remained associated with PAV progression (0.123; 0.014-0.23; p=0.027). Lower effect sizes for the association of age with PAV progression were observed for patients with partial control of LDL-cholesterol and SBP and were not significantly associated with PAV progression when both LDL-cholesterol and SBP were not controlled (0.099; 0.032-0.167; p=0.004 and 0.042; -0.056 to 0.14; p=0.40, respectively).

CONCLUSIONS

Patient age is directly associated with coronary atheroma progression independently of traditional cardiovascular risk factors. In the setting of poor risk factor control, the influence of age on coronary artery disease progression is attenuated.

Rosuvastatin effect on atherosclerotic plaque metabolism: A subclinical atherosclerosis imaging study with 18F-NaF PET-CT

BACKGROUND AND AIMS

Atherosclerotic plaque fluorine-18 sodium fluoride (18F-NaF) uptake on positron emission tomography with computed tomography (PET-CT) identifies active microcalcification and has been shown to correlate with clinical instability in patients with cardiovascular (CV) disease. Statin therapy promotes coronary macrocalcification over time. Our aim was to investigate rosuvastatin effect on atheroma 18F-NaF uptake.

METHODS

Subjects with high CV risk but without CV events underwent 18F-NaF-PET-CT in a single-centre. Those with subclinical atherosclerosis and significant 18F-NaF plaque uptake were included in a single-arm clinical trial, treated with rosuvastatin 20 mg/daily for six months, and re-evaluated by 18F-NaF-PET-CT. Primary endpoint was reduction in maximum atheroma 18F-NaF uptake in the coronary, aortic or carotid arteries, assessed by the tissue-to-background ratio (TBR). The secondary endpoint was corrected uptake per lesion (CUL) variation.

RESULTS

Forty individuals were enrolled and 38 included in the pharmacological trial; mean age was 64 years, two-thirds were male and most were diabetic. The 10-year expected CV risk was 9.5% (6.0-15.3) for SCORE2 and 31.7 ± 18.7% for ASCVD systems. After six months of rosuvastatin treatment (n = 34), low-density lipoprotein cholesterol lowered from 133.6 ± 33.8 to 58.8 ± 20.7 mg dL-1 (60% relative reduction, p < 0.01). There was a significant 19% reduction in maximum plaque 18F-NaF uptake after treatment, from 1.96 (1.78-2.22) to 1.53 (1.40-2.10), p < 0.001 (primary endpoint analysis). The secondary endpoint CUL was reduced by 23% (p = 0.003).

CONCLUSION

In a single-centre non-randomized clinical trial of high CV risk individuals with subclinical atherosclerosis, the maximum atherosclerotic plaque 18F-NaF uptake was significantly reduced after six months of high-intensity statin.

Reversal of atherosclerosis by restoration of vascular copper homeostasis

Atherosclerosis has traditionally been considered as a disorder characterized by the accumulation of cholesterol and thrombotic materials within the arterial wall. However, it is now understood to be a complex inflammatory disease involving multiple factors. Central to the pathogenesis of atherosclerosis are the interactions among monocytes, macrophages, and neutrophils, which play pivotal roles in the initiation, progression, and destabilization of atherosclerotic lesions. Recent advances in our understanding of atherosclerosis pathogenesis, coupled with results obtained from experimental interventions, lead us to propose the hypothesis that atherosclerosis may be reversible. This paper outlines the evolution of this hypothesis and presents corroborating evidence that supports the potential for atherosclerosis regression through the restoration of vascular copper homeostasis. We posit that these insights may pave the way for innovative therapeutic approaches aimed at the reversal of atherosclerosis.

Characteristics of Coronary Atherosclerosis Related to Plaque Burden Regression During Treatment With Alirocumab: The ARCHITECT Study

BACKGROUND

Intensive lipid-lowering therapy may induce coronary atherosclerosis regression. Nevertheless, the factors underlying the effect of lipid-lowering therapy on disease regression remain poorly characterized. Our aim was to determine which characteristics of atherosclerotic plaque are associated with a greater reduction in coronary plaque burden (PB) after treatment with alirocumab in patients with familial hypercholesterolemia.

METHODS

The ARCHITECT study (Effect of Alirocumab on Atherosclerotic Plaque Volume, Architecture and Composition) is a phase IV, open-label, multicenter, single-arm clinical trial to assess the effect of the treatment with alirocumab for 78 weeks on the coronary atherosclerotic PB and its characteristics in subjects with familial hypercholesterolemia without clinical atherosclerotic cardiovascular disease. Participants underwent a coronary computed tomographic angiography at baseline and a final one at 78 weeks. Every patient received alirocumab 150 mg subcutaneously every 14 days in addition to high-intensity statin therapy.

RESULTS

One hundred and four patients were enrolled. Median age was 53.3 (46.2-59.4) years and 54 were women (51.9%). The global coronary PB changed from 34.6% (32.5%-36.8%) at entry to 30.4% (27.4%-33.4%) at follow-up, which is -4.6% (-7.7% to -1.9%; P<0.001) reduction. A decrease in the percentage of unstable core (fibro-fatty+necrotic plaque; from 14.1 [7.9-22.3] to 8.0 [6.4-10.6]; -6.6%; P<0.001) was found. A greater PB (β, 0.36 [0.13-0.59]; P=0.002) and a higher proportion of unstable core (β, 0.15 [0.08-0.22]; P<0.001) were significantly related to PB regression.

CONCLUSIONS

Treatment with alirocumab in addition to high-intensity statin therapy might produce a greater PB regression in patients with familial hypercholesterolemia with higher baseline PB and in those with larger unstable core. Further studies are needed to corroborate the hypothesis raised by these results.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT05465278.

Concomitant Coronary Atheroma Regression and Stabilization in Response to Lipid-Lowering Therapy

BACKGROUND

The frequency, characteristics, and outcomes of patients treated with high-intensity lipid-lowering therapy and showing concomitant atheroma volume reduction, lipid content reduction, and increase in fibrous cap thickness (ie, triple regression) are unknown.

OBJECTIVES

This study was designed to investigate rates, determinants, and prognostic implications of triple regression in patients presenting with acute myocardial infarction and treated with high-intensity lipid-lowering therapy.

METHODS

The PACMAN-AMI (Effects of the PCSK9 Antibody Alirocumab on Coronary Atherosclerosis in Patients with Acute Myocardial Infarction) trial used serial intravascular ultrasound, near-infrared spectroscopy, and optical coherence tomography to compare the effects of alirocumab vs placebo in patients receiving high-intensity statin therapy. Triple regression was defined by the combined presence of percentage of atheroma volume reduction, maximum lipid core burden index within 4 mm reduction, and minimal fibrous cap thickness increase. Clinical outcomes at 1-year follow-up were assessed.

RESULTS

Overall, 84 patients (31.7%) showed triple regression (40.8% in the alirocumab group vs 23.0% in the placebo group; P = 0.002). On-treatment low-density lipoprotein cholesterol levels were lower in patients with vs without triple regression (between-group difference: -27.1 mg/dL; 95% CI: -37.7 to -16.6 mg/dL; P < 0.001). Triple regression was independently predicted by alirocumab treatment (OR: 2.83; 95% CI: 1.57-5.16; P = 0.001) and a higher baseline maximum lipid core burden index within 4 mm (OR: 1.03; 95% CI: 1.01-1.06; P = 0.013). The composite clinical endpoint of death, myocardial infarction, and ischemia-driven revascularization occurred less frequently in patients with vs without triple regression (8.3% vs 18.2%; P = 0.04).

CONCLUSIONS

Triple regression occurred in one-third of patients with acute myocardial infarction who were receiving high-intensity lipid-lowering therapy and was associated with alirocumab treatment, higher baseline lipid content, and reduced cardiovascular events. (Vascular Effects of Alirocumab in Acute MI-Patients [PACMAN-AMI]; NCT03067844).

Impact of alirocumab on plaque regression and haemodynamics of non-culprit arteries in patients with acute myocardial infarction: a prespecified substudy of the PACMAN-AMI trial

BACKGROUND

Treatment with proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors on top of statins leads to plaque regression and stabilisation. The effects of PCSK9 inhibitors on coronary physiology and angiographic diameter stenosis (DS%) are unknown.

AIMS

This study aimed to investigate the effects of the PCSK9 inhibitor alirocumab on coronary haemodynamics as assessed by quantitative flow ratio (QFR) and DS% by three-dimensional quantitative coronary angiography (3D-QCA) in non-infarct-related arteries (non-IRA) among acute myocardial infarction (AMI) patients.

METHODS

This was a prespecified substudy of the randomised controlled PACMAN-AMI trial, comparing alirocumab versus placebo on top of rosuvastatin. QFR and 3D-QCA were assessed at baseline and 1 year in any non-IRA ≥2.0 mm and 3D-QCA DS% >25%. The prespecified primary endpoint was the number of patients with a mean QFR increase at 1 year, and the secondary endpoint was the change in 3D-QCA DS%.

RESULTS

Of 300 enrolled patients, 265 had serial follow-up, of which 193 underwent serial QFR/3D-QCA analysis in 282 non-IRA. At 1 year, QFR increased in 50/94 (53.2%) patients with alirocumab versus 40/99 (40.4%) with placebo (Δ12.8%; odds ratio 1.7, 95% confidence interval [CI]: 0.9 to 3.0; p=0.076). DS% decreased by 1.03±7.28% with alirocumab and increased by 1.70±8.27% with placebo (Δ-2.50%, 95% CI: -4.43 to -0.57; p=0.011).

CONCLUSIONS

Treatment of AMI patients with alirocumab versus placebo for 1 year resulted in a significant regression in angiographic DS%, whereas no overall improvement of coronary haemodynamics was observed.

CLINICALTRIALS

gov: NCT03067844.

Intravascular Ultrasound and Optical Coherent Tomography Combined Catheter

Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) are established intravascular imaging tools for evaluating plaque characteristics and volume, together with guiding percutaneous coronary interventions. The high tissue penetration of IVUS facilitates assessment of the entire vessel wall, whereas the higher resolution of OCT allows detailed assessment of endoluminal structures. A combined IVUS-OCT probe works synergistically, facilitating a greater understanding of de novo coronary artery disease and a better correlation with pathological specimens. In this review, we discuss the rationale and potential roles of the combined IVUS-OCT catheter system.

Morphologies and composition changes in nonculprit subclinical atherosclerosis in diabetic versus nondiabetic patients with acute coronary syndrome who underwent long-term statin therapy

Although patients are undergoing similar lipid-lowering therapy (LLT) with statins, the outcomes of coronary plaque in diabetic mellitus (DM) and non-DM patients are different. Clinical data of 239 patients in this observational study with acute coronary syndrome was from our previous randomized trial were analyzed at 3 years, and 114 of them underwent OCT detection at baseline and the 1-year follow-up were re-anlayzed by a novel artificial intelligence imaging software for nonculprit subclinical atherosclerosis (nCSA). Normalized total atheroma volume changes (ΔTAVn) of nCSA were the primary endpoint. Plaque progression (PP) was defined as any increase in ΔTAVn. DM patients showed more PP in nCSA (ΔTAVn; 7.41 (- 2.82, 11.85) mm³ vs. - 1.12 (- 10.67, 9.15) mm³, p = 0.009) with similar reduction of low-density lipoprotein cholesterol (LDL-C) from baseline to 1-year. The main reason is that the lipid component in nCSA increases in DM patients and non-significantly decreases in non-DM patients, which leads to a significantly higher lipid TAVn (24.26 (15.05, 40.12) mm³ vs. 16.03 (6.98, 26.54) mm³, p = 0.004) in the DM group than in the non-DM group at the 1-year follow-up. DM was an independent predictor of PP in multivariate logistic regression analysis (OR = 2.731, 95% CI 1.160-6.428, p = 0.021). Major adverse cardiac events (MACEs) related to nCSA at 3 years were higher in the DM group than in the non-DM group (9.5% vs. 1.7%, p = 0.027). Despite a comparable reduction in LDL-C levels after LLT, more PP with an increase in the lipid component of nCSA and a higher incidence of MACEs at the 3-year follow-up was observed in DM patients.Trial registration: ClinicalTrials.gov. identifier: NCT02140801.

Layered plaque and plaque volume in patients with acute coronary syndromes

BACKGROUND

Layered plaque is a signature of previous subclinical plaque destabilization and healing. Following plaque disruption, thrombus becomes organized, resulting in creation of a new layer, which might contribute to rapid step-wise progression of the plaque. However, the relationship between layered plaque and plaque volume has not been fully elucidated.

METHODS

Patients who presented with acute coronary syndromes (ACS) and underwent pre-intervention optical coherence tomography (OCT) and intravascular ultrasound (IVUS) imaging of the culprit lesion were included. Layered plaque was identified by OCT, and plaque volume around the culprit lesion was measured by IVUS.

RESULTS

Among 150 patients (52 with layered plaque; 98 non-layered plaque), total atheroma volume (183.3 mm³[114.2 mm³ to 275.0 mm³] vs. 119.3 mm³[68.9 mm³ to 185.5 mm³], p = 0.004), percent atheroma volume (PAV) (60.1%[54.7-60.1%] vs. 53.7%[46.8-60.6%], p = 0.001), and plaque burden (86.5%[81.7-85.7%] vs. 82.6%[77.9-85.4%], p = 0.001) were significantly greater in patients with layered plaques than in those with non-layered plaques. When layered plaques were divided into multi-layered or single-layered plaques, PAV was significantly greater in patients with multi-layered plaques than in those with single-layered plaques (62.1%[56.8-67.8%] vs. 57.5%[48.9-60.1%], p = 0.017). Layered plaques, compared to those with non-layered pattern, had larger lipid index (1958.0[420.9 to 2502.9] vs. 597.2[169.1 to 1624.7], p = 0.014).

CONCLUSION

Layered plaques, compared to non-layered plaques, had significantly greater plaque volume and lipid index. These results indicate that plaque disruption and the subsequent healing process significantly contribute to plaque progression at the culprit lesion in patients with ACS.

CLINICAL TRIAL REGISTRATION

http://www.

CLINICALTRIALS

gov , NCT01110538, NCT03479723, UMIN000041692.

Effect of Alirocumab Added to High-Intensity Statin Therapy on Coronary Atherosclerosis in Patients With Acute Myocardial Infarction: The PACMAN-AMI Randomized Clinical Trial

IMPORTANCE

Coronary plaques that are prone to rupture and cause adverse cardiac events are characterized by large plaque burden, large lipid content, and thin fibrous caps. Statins can halt the progression of coronary atherosclerosis; however, the effect of the proprotein convertase subtilisin kexin type 9 inhibitor alirocumab added to statin therapy on plaque burden and composition remains largely unknown.

OBJECTIVE

To determine the effects of alirocumab on coronary atherosclerosis using serial multimodality intracoronary imaging in patients with acute myocardial infarction.

DESIGN, SETTING, AND PARTICIPANTS

The PACMAN-AMI double-blind, placebo-controlled, randomized clinical trial (enrollment: May 9, 2017, through October 7, 2020; final follow-up: October 13, 2021) enrolled 300 patients undergoing percutaneous coronary intervention for acute myocardial infarction at 9 academic European hospitals.

INTERVENTIONS

Patients were randomized to receive biweekly subcutaneous alirocumab (150 mg; n = 148) or placebo (n = 152), initiated less than 24 hours after urgent percutaneous coronary intervention of the culprit lesion, for 52 weeks in addition to high-intensity statin therapy (rosuvastatin, 20 mg).

MAIN OUTCOMES AND MEASURES

Intravascular ultrasonography (IVUS), near-infrared spectroscopy, and optical coherence tomography were serially performed in the 2 non-infarct-related coronary arteries at baseline and after 52 weeks. The primary efficacy end point was the change in IVUS-derived percent atheroma volume from baseline to week 52. Two powered secondary end points were changes in near-infrared spectroscopy-derived maximum lipid core burden index within 4 mm (higher values indicating greater lipid content) and optical coherence tomography-derived minimal fibrous cap thickness (smaller values indicating thin-capped, vulnerable plaques) from baseline to week 52.

RESULTS

Among 300 randomized patients (mean [SD] age, 58.5 [9.7] years; 56 [18.7%] women; mean [SD] low-density lipoprotein cholesterol level, 152.4 [33.8] mg/dL), 265 (88.3%) underwent serial IVUS imaging in 537 arteries. At 52 weeks, mean change in percent atheroma volume was -2.13% with alirocumab vs -0.92% with placebo (difference, -1.21% [95% CI, -1.78% to -0.65%], P < .001). Mean change in maximum lipid core burden index within 4 mm was -79.42 with alirocumab vs -37.60 with placebo (difference, -41.24 [95% CI, -70.71 to -11.77]; P = .006). Mean change in minimal fibrous cap thickness was 62.67 μm with alirocumab vs 33.19 μm with placebo (difference, 29.65 μm [95% CI, 11.75-47.55]; P = .001). Adverse events occurred in 70.7% of patients treated with alirocumab vs 72.8% of patients receiving placebo.

CONCLUSIONS AND RELEVANCE

Among patients with acute myocardial infarction, the addition of subcutaneous biweekly alirocumab, compared with placebo, to high-intensity statin therapy resulted in significantly greater coronary plaque regression in non-infarct-related arteries after 52 weeks. Further research is needed to understand whether alirocumab improves clinical outcomes in this population.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03067844.

Pathophysiology of Atherosclerosis

Atherosclerosis is the main risk factor for cardiovascular disease (CVD), which is the leading cause of mortality worldwide. Atherosclerosis is initiated by endothelium activation and, followed by a cascade of events (accumulation of lipids, fibrous elements, and calcification), triggers the vessel narrowing and activation of inflammatory pathways. The resultant atheroma plaque, along with these processes, results in cardiovascular complications. This review focuses on the different stages of atherosclerosis development, ranging from endothelial dysfunction to plaque rupture. In addition, the post-transcriptional regulation and modulation of atheroma plaque by microRNAs and lncRNAs, the role of microbiota, and the importance of sex as a crucial risk factor in atherosclerosis are covered here in order to provide a global view of the disease.

Association of Statin Treatment With Progression of Coronary Atherosclerotic Plaque Composition

Importance

The density of atherosclerotic plaque forms the basis for categorizing calcified and noncalcified morphology of plaques.

Objective

To assess whether alterations in plaque across a range of density measurements provide a more detailed understanding of atherosclerotic disease progression.

Design, Setting, and Participants

This cohort study enrolled 857 patients who underwent serial coronary computed tomography angiography 2 or more years apart and had quantitative measurements of coronary plaques throughout the entire coronary artery tree. The study was conducted from 2013 to 2016 at 13 sites in 7 countries.

Main Outcomes and Measures

The main outcome was progression of plaque composition of individual coronary plaques. Six plaque composition types were defined on a voxel-level basis according to the plaque attenuation (expressed in Hounsfield units [HU]): low attenuation (-30 to 75 HU), fibro-fatty (76-130 HU), fibrous (131-350 HU), low-density calcium (351-700 HU), high-density calcium (701-1000 HU), and 1K (>1000 HU). The progression rates of these 6 compositional plaque types were evaluated according to the interaction between statin use and baseline plaque volume, adjusted for risk factors and time interval between scans. Plaque progression was also examined based on baseline calcium density. Analysis was performed among lesions matched at baseline and follow-up. Data analyses were conducted from August 2019 through March 2020.

Results

In total, 2458 coronary lesions in 857 patients (mean [SD] age, 62.1 [8.7] years; 540 [63.0%] men; 548 [63.9%] received statin therapy) were included. Untreated coronary lesions increased in volume over time for all 6 compositional types. Statin therapy was associated with volume decreases in low-attenuation plaque (β, -0.02; 95% CI, -0.03 to -0.01; P = .001) and fibro-fatty plaque (β, -0.03; 95% CI, -0.04 to -0.02; P < .001) and greater progression of high-density calcium plaque (β, 0.02; 95% CI, 0.01-0.03; P < .001) and 1K plaque (β, 0.02; 95% CI, 0.01-0.03; P < .001). When analyses were restricted to lesions without low-attenuation plaque or fibro-fatty plaque at baseline, statin therapy was not associated with a change in overall calcified plaque volume (β, -0.03; 95% CI, -0.08 to 0.02; P = .24) but was associated with a transformation toward more dense calcium. Interaction analysis between baseline plaque volume and calcium density showed that more dense coronary calcium was associated with less plaque progression.

Conclusions and Relevance

The results suggest an association of statin use with greater rates of transformation of coronary atherosclerosis toward high-density calcium. A pattern of slower overall plaque progression was observed with increasing density. All findings support the concept of reduced atherosclerotic risk with increased densification of calcium.

Utilization of IVUS improves all-cause mortality in patients undergoing invasive coronary angiography

Background and aims

Available data suggest that the use of IVUS for guidance of percutaneous coronary interventions (PCIs) improves the prognosis of patients undergoing complex interventions. We aimed to examine how the utilization of intravascular ultrasound (IVUS) affects patient survival irrespective of procedure complexity.

Methods

The present analysis is based on the longitudinal ECAD registry of consecutive patients undergoing coronary angiography between 2004 and 2019. The incidence of death due to any cause was evaluated during a mean follow-up of 3.4 years. Cox regression analysis was used to determine the association of IVUS utilization with incident mortality.

Results

Overall, data from 30,814 coronary angiography exams (mean age 64.9 ± 12.5 years, 70.3% male) were included, among which 4991 procedures (16.2%) were guided by IVUS. Utilization of IVUS was associated with a 35% reduction in mortality, independent of traditional risk factors (0.64(0.58-0.71), p < 0.0001). The effect of IVUS on mortality was equally present in patients undergoing IVUS-guided coronary interventions (0.75[0.67-0.84], p < 0.0001) as well as purely diagnostic coronary angiography exams (0.62[0.56-0.72], p < 0.0001). In patients without coronary intervention, IVUS utilization led to a higher frequency of aspirin (82.6% vs. 61.9% for IVUS vs. no IVUS, p < 0.0001) and statin therapy (74.9% vs. 62.5%, p < 0.0001).

Conclusions

In a large longitudinal registry cohort of patients undergoing invasive coronary angiography, IVUS utilization was associated with lower long-term mortality. The beneficial role of IVUS utilization on survival was equally present for coronary interventions and diagnostic coronary angiograms. Our results support the use of intravascular imaging for decision making in interventional cardiology.

Relationship between arterial remodelling and serial changes in coronary atherosclerosis by intravascular ultrasound: an analysis of the IBIS-4 study

AIMS

Arterial remodelling is an important determinant of coronary atherosclerosis. Assessment of the remodelling index, comparing a lesion to a local reference site, is a suboptimal correlate of serial vascular changes. We assessed a novel approach which, unlike the local-reference approach, uses the entire artery's global remodelling as reference.

METHODS AND RESULTS

Serial (baseline and 13 months) intravascular ultrasound was performed in 146 non-infarct-related arteries of 82 patients treated with high-intensity statin. Arteries were divided into 3-mm segments (n = 1479), and focal remodelling was characterized in individual segments at both timepoints applying the global arterial reference approach. First, we compared preceding vascular changes in relation to follow-up remodelling. Second, we examined whether baseline remodelling predicts subsequent plaque progression/regression. At follow-up, segments with constrictive vs. compensatory or expansive remodelling had greater preceding reduction of vessel area (-0.67 vs. -0.38 vs. -0.002 mm2; P < 0.001) and lumen area (-0.82 vs. -0.09 vs. 0.40 mm2; P < 0.001). Overall, we found significant regression in percent atheroma volume (PAV) [-0.80% (-1.41 to -0.19)]. Segments with constrictive remodelling at baseline had greater subsequent PAV regression vs. modest regression in the compensatory, and PAV progression in the expansive remodelling group (-6.14% vs. -0.71% vs. 2.26%; P < 0.001). Lesion-level analyses (n = 118) showed no differences when remodelling was defined by the local reference approach at baseline or follow-up.

CONCLUSION

Remodelling assessment using a global arterial reference approach, but not the commonly used, local reference site approach, correlated reasonably well with serial changes in arterial dimensions and identified arterial segments with subsequent PAV progression despite intensive statin treatment and overall atheroma regression.

Advances in IVUS/OCT and Future Clinical Perspective of Novel Hybrid Catheter System in Coronary Imaging

Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) have been developed and improved as both diagnostic and guidance tools for interventional procedures over the past three decades. IVUS has a resolution of 100 μm with a high tissue penetration and capability of assessing the entire structure of a coronary artery including the external elastic membrane, whereas OCT has a higher resolution of 10–20 μm to assess endoluminal structures with a limited tissue penetration compared to IVUS. Recently, two companies, CONAVI and TERUMO, integrated IVUS and OCT into a single catheter system. With their inherent strength and limitations, the combined IVUS and OCT probes are complementary and work synergistically to enable a comprehensive depiction of coronary artery. In this review, we summarize the performance of the two intracoronary imaging modalities—IVUS and OCT—and discuss the expected potential of the novel hybrid IVUS–OCT catheter system in the clinical field.

Rivaroxaban With or Without Aspirin for the Secondary Prevention of Cardiovascular Disease: Clinical Implications of the COMPASS Trial

The COMPASS trial compared the impact of the selective direct factor Xa inhibitor, rivaroxaban, as monotherapy or in combination with aspirin on major adverse cardiovascular events (MACE) in patients with stable atherosclerotic disease. Patients treated with rivaroxaban 2.5 mg twice daily in combination with aspirin experienced fewer cardiovascular events but more bleeding complications than those who received aspirin monotherapy. In contrast, a higher dose of rivaroxaban (5 mg twice daily) and aspirin produced no clinical benefit and continued to be associated with greater bleeding rates than aspirin. Examining this study in the context of other trials of anticoagulant therapy in atherosclerotic vascular disease, this review attempts to place the role of very low-dose rivaroxaban in clinical context and highlights areas for future research.

Shrinkage as a potential mechanism of recurrent clinical events in patients with a large vulnerable plaque

AIMS

This study aimed to investigate the progression and vascular shrinkage of vulnerable plaque lesions with a plaque burden at least 70% among patients with coronary artery disease by optical coherence tomography (OCT) and intravascular ultrasound (IVUS).

METHODS

Fifty-six OCT-identified vulnerable plaques from 47 patients were included among coronary angiography-identified nonculprit/nontarget lesions. Serial IVUS images were used to assess plaque progression and vascular shrinkage.

RESULTS

Thirty-five small vulnerable plaques (plaque burden <70%, group A) and 21 large vulnerable plaques (plaque burden ≥70%, group B) were identified. The IVUS results at baseline show that mean plaque areas (P < 0.001) and the percentage atheroma volume (PAV) (P < 0.0001) were greater and the minimal lumen area (P < 0.0001) was smaller in group B. The absolute and relative changes in the PAV and mean plaque area from baseline to follow-up were not significantly different. However, the lesions exhibited vessel shrinkage [the mean external elastic membrane (EEM) area (P = 0.02) and mean lumen area (P = 0.03) were significantly smaller in group B] from baseline to follow-up. Patients in group B also exhibited clinical events (recurrent angina symptoms) during the follow-up period. Positive correlations were found between changes in the mean plaque area and the mean EEM area in large vulnerable plaques (r = 0.61, P < 0.0001) and between changes in the mean EEM area and the mean lumen area in large vulnerable plaques (r = 0.61, P < 0.0001).

CONCLUSION

Vulnerable plaque progression was not different between small and large vulnerable plaques. However, large vulnerable plaque lesions tended to exhibit vascular shrinkage, which is possible a cause of coronary artery lumen loss in patients with large vulnerable plaques.

Hypermethylation of the Micro-RNA 145 Promoter Is the Key Regulator for NLRP3 Inflammasome-Induced Activation and Plaque Formation

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miR-145 in vessels decreases with plaque progression.

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DNMT1 and TET2 dynamic imbalance leads to miR-145 promoter hypermethylation.

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Reduction of miR-145 activates NLRP3 inflammasome through CD137/NFATc1 signaling.

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DNMT1 and TET2 could be promising therapeutic candidates for atherosclerosis in the future.

Two major issues are involved in clinical atherosclerosis treatment. First, there are no significant clinical markers for early diagnosis of atherosclerosis. Second, the plaque will not regress once it initiates even if the risk factors are removed. In this paper, the research shows that the hypermethylation level of the microRNA 145 (miR-145) promoter is related to a DNMT1 and TET2 dynamic imbalance. The reduction of miR-145 causes NLRP3 (nucleotide-binding oligomerization domain-like receptor protein 3) inflammasome activation through CD137/NFATc1 signaling. These findings could be a potential target for plaque regression in the future.

Improvement in LDL is associated with decrease in non-calcified plaque volume on coronary CTA as measured by automated quantitative software

BACKGROUND

Computed tomography coronary angiography (CTA) can be used for assessment of plaque characteristics; however, quantitative assessment of changes in plaque composition in response to LDL lowering has not been performed with CTA. We sought to assess the association between LDL reduction and changes in plaque composition with quantitative CTA.

METHODS

Quantification of total, calcified, non-calcified and low-density non-calcified plaque volumes (TPV, CPV, NCPV and LD-NCPV) was performed using semi-automated software in 234 vessels from 116 consecutive patients (89 men, 60 ± 10 years) with baseline LDL>70 mg/dl. Significant reduction in LDL was defined as a decrease by >10% of baseline LDL. Changes (Δ) in plaque volumes between the second and baseline study were compared between patients with LDL reduction (n = 63) and those with no decrease in LDL (n = 53).

RESULTS

Median LDL at baseline was 98 mg/dl [interquartile range (IQR) 83-119 mg/dl] and median ΔLDL was -14 mg/dl (IQR -38 to 3 mg/dl). Mean interval between sequential CTA was 3.5 ± 1.6 years. TPV, NCPV, and LD-NCPV decreased in patients with a reduction in LDL compared to baseline; whereas, patients without reduction in LDL experienced an increase in TPV, NCPV and LD-NCPV. After adjusting for age, statin use, diabetes, baseline LDL and baseline TPV, reduction in LDL was associated with a decrease in TPV (P = 0.005), NCPV (P = 0.002) and LD-NCPV (P = 0.011) compared to patients without a reduction in LDL.

CONCLUSION

Reduction in LDL was associated with beneficial changes in the amount and composition of noncalcified plaque as measured using semi-automated quantitative software by CTA.

Atherosclerotic plaque vulnerability in the statin era

Life style changes and improved medical therapy have decreased cardiovascular mortality in many countries over the last decades. This has been accompanied by changes in disease characteristics including more non-ST segment elevation myocardial infraction and less vulnerable plaques as assessed by histological analysis of surgical specimens. However, many patients with established disease still suffer from recurrent cardiovascular events in spite of treatment with state-of-the-art-therapy including statins. It is likely that this reflects a state of the disease in which statins control the pro-inflammatory effects of lipids allowing other statin-unresponsive disease mechanisms to become increasingly important. If this assumption is correct it means that patients with established disease with time will get insuffient protection by current therapies alone. Against this background it is critical to reach a better understanding of alternative mechanisms for plaque vulnerability. Examples of such mechanisms include altered patterns of blood flow caused by plaque stenosis resulting in down-regulation of the anti-inflammatory and anti-thrombotic signals in the endothelium, impaired vascular repair associated with diabetes and plaque inflammation driven by cholesterol crystals, infectious pathogens as well as autoimmune responses against modified plaque components. Novel biomarkers and other diagnostics are needed to establish the clinical importance of these mechanisms as well as to determine how they are affected by current treatments. Consequently, there will also be a need for development of new treatments targeting these mechanisms and that can act in concert with current therapies.

Coronary Artery Plaque Regression by a PCSK9 Antibody and Rosuvastatin in Double-heterozygous Familial Hypercholesterolemia with an LDL Receptor Mutation and a PCSK9 V4I Mutation

The low-density lipoprotein-cholesterol (LDL-C) level of a 38-year-old man diagnosed with acute coronary syndrome was 257 mg/dL. The administration of a proprotein convertase subtilisin-kexin type 9 (PCSK9) antibody in addition to rosuvastatin plus ezetimibe was initiated, reducing his LDL-C level to 37 mg/dL. A genetic analysis revealed both an LDL receptor (LDLR) mutation and a PCSK9 V4I mutation. Nine months after revascularization, intravascular ultrasound revealed plaque regression in the coronary arteries. LDLR/PCSK9 mutation carriers are prone to coronary artery disease. Intensive LDL-C lowering by including PCSK9 antibody was associated with coronary plaque regression, suggesting the expectation of prognosis improvement.

Association of Dyslipidemia and Sex With Coronary Artery Calcium Assessed by Coronary Computed Tomography Angiography

Previous studies reporting that statin increases coronary artery calcium (CAC) were conducted exclusively on patients with statin as a prevention, regardless of the presence or absence of dyslipidemia. The impact of sex on CAC has not been fully evaluated. We aimed to determine the association of dyslipidemia and sex with CAC using 320-row multi-detector computed tomography (MDCT).Of the 356 consecutive patients who underwent coronary MDCT, 251 patients were enrolled, after excluding those with prior stenting and/or coronary bypass grafting or images showing motion artifacts. The primary outcome measures were the percent calcium volume (PCV) and percent atheroma volume (PAV) per coronary vessel.Multivariable analyses indicated that PCV was significantly higher in dyslipidemia patients without statins than in the subjects without dyslipidemia [partial regression coefficient (PRC): 2.59, 95% confidence interval (CI): 0.83 to 4.34, P = 0.004]. In contrast, PCV was similar in dyslipidemia patients taking statins and those without dyslipidemia (PRC: -1.09, 95% CI: -2.82 to 0.65, P = 0.22). There was no significant difference in PCV between men and women, although women exhibited a significantly lower PAV (PRC: -2.87, 95% CI: -4.54 to -1.20, P = 0.001).In low-risk patients, these results could be translated into hypotheses, which should be tested in future prospective studies. Furthermore, there was no significant difference in CAC between men and women, but women had lower PAV than men.

Regression of coronary atherosclerosis with infusions of the high-density lipoprotein mimetic CER-001 in patients with more extensive plaque burden

BACKGROUND

CER-001 is an engineered pre-beta high-density lipoprotein (HDL) mimetic, which rapidly mobilizes cholesterol. Infusion of CER-001 3 mg/kg exhibited a potentially favorable effect on plaque burden in the CHI-SQUARE (Can HDL Infusions Significantly Quicken Atherosclerosis Regression) study. Since baseline atheroma burden has been shown as a determinant for the efficacy of HDL infusions, the degree of baseline atheroma burden might influence the effect of CER-001.

METHODS

CHI-SQUARE compared the effect of 6 weekly infusions of CER-001 (3, 6 and 12 mg/kg) vs. placebo on coronary atherosclerosis in 369 patients with acute coronary syndrome (ACS) using serial intravascular ultrasound (IVUS). Baseline percent atheroma volume (B-PAV) cutoff associated with atheroma regression following CER-001 infusions was determined by receiver-operating characteristics curve analysis. 369 subjects were stratified according to the cutoff. The effect of CER-001 at different doses was compared to placebo in each group.

RESULTS

A B-PAV ≥30% was the optimal cutoff associated with PAV regression following CER-001 infusions. CER-001 induced PAV regression in patients with B-PAV ≥30% but not in those with B-PAV <30% (-0.45%±2.65% vs. +0.34%±1.69%, P=0.01). Compared to placebo, the greatest PAV regression was observed with CER-001 3mg/kg in patients with B-PAV ≥30% (-0.96%±0.34% vs. -0.25%±0.31%, P=0.01), whereas there were no differences between placebo (+0.09%±0.36%) versus CER-001 in patients with B-PAV <30% (3 mg/kg; +0.41%±0.32%, P=0.39; 6 mg/kg; +0.27%±0.36%, P=0.76; 12 mg/kg; +0.32%±0.37%, P=0.97).

CONCLUSIONS

Infusions of CER-001 3 mg/kg induced the greatest atheroma regression in ACS patients with higher B-PAV. These findings identify ACS patients with more extensive disease as most likely to benefit from HDL mimetic therapy.

The Yin–Yang Dynamics of DNA Methylation Is the Key Regulator for Smooth Muscle Cell Phenotype Switch and Vascular Remodeling

Objective—

DNA methylation plays an important role in chronic diseases such as atherosclerosis, yet the mechanisms are poorly understood. The objective of our study is to indicate the regulatory mechanisms of DNA methylation in vascular smooth muscle cells (VSMCs) and its roles in atherosclerosis.

Approach and Results—

In ApoE −/− mice fed a Western diet, DNA methyltransferase inhibitor, 5-aza-2′-deoxycytidine, significantly attenuated atherosclerotic lesions (20.1±2.2% versus 30.8±7.5%; P =0.016) and suppressed DNA methyltransferase activity and concomitantly decreased global 5-methylcytosine content in atherosclerotic lesions of ApoE −/− mice. Using a carotid ligation model, we found that 5-aza-2′-deoxycytidine also dramatically inhibited neointimal formation (intimal area: 2.25±0.14×10 4 versus 4.07±0.22×10 4 μm 2 ; P <0.01). Abnormal methylation status at the promoter of ten–eleven translocation 2, one of the key demethylation enzymes in mammals, was ameliorated after 5-aza-2′-deoxycytidine treatment, which in turn caused an increase in global DNA hydroxymethylation and 5-hydroxymethylcytosine enrichment at the promoter of Myocardin. In vitro, 5-aza-2′-deoxycytidine treatment or DNA methyltransferase 1 knockdown decreased global 5-methylcytosine content and restored Myocardin expression in VSMCs induced by platelet-derived growth factor, thus preventing excessive VSMCs dedifferentiation, proliferation, and migration. Furthermore, DNA methyltransferase 1 binds to ten–eleven translocation 2 promoter and is required for ten–eleven translocation 2 methylation in VSMCs.

Conclusions—

The inhibitory effects of DNA demethylation on global 5-methylcytosine content and ten–eleven translocation 2 hypermethylation in atherosclerotic aorta can recover 5-hydroxymethylcytosine enrichment at the Myocardin promoter and prevent VSMC dedifferentiation and vascular remodeling.

Plaque progression assessed by a novel semi-automated quantitative plaque software on coronary computed tomography angiography between diabetes and non-diabetes patients: A propensity-score matching study

BACKGROUND AND AIMS

We aimed at investigating whether diabetes is associated with progression in coronary plaque components.

METHODS

We identified 142 study subjects undergoing serial coronary computed tomography angiography. The resulting propensity score was applied 1:1 to match diabetic patients to non-diabetic patients for clinical risk factors, prior coronary stenting, coronary artery calcium (CAC) score and the serial scan interval, resulting in the 71 diabetes and 71 non-diabetes patients. Coronary plaque (total, calcified, non-calcified including fibrous, fibrous-fatty and low attenuation plaque [LAP]) volume normalized by total coronary artery length was measured using semi-automated plaque software and its change overtime between diabetic and non-diabetic patients was evaluated.

RESULTS

The matching was successful without significant differences between the two groups in all matched variables. The baseline volumes in each plaque also did not differ. During a mean scan interval of 3.4 ± 1.8 years, diabetic patients showed a 2-fold greater progression in normalized total plaque volume (TPV) than non-diabetes patients (52.8 mm³vs. 118.3 mm³, p = 0.005). Multivariable linear regression model revealed that diabetes was associated with normalized TPV progression (β 72.3, 95%CI 24.3-120.3). A similar trend was observed for the non-calcified components, but not calcified plaque (β 3.8, 95%CI -27.0-34.7). Higher baseline CAC score was found to be associated with total, non-calcified and calcified plaque progression. However, baseline non-calcified volume but not CAC score was associated with LAP progression.

CONCLUSIONS

The current study among matched patients indicates diabetes is associated with a greater plaque progression. Our results show the need for strict adherence of diabetic patients to the current preventive guidelines.

Effects of statin therapy on progression of mild noncalcified coronary plaque assessed by serial coronary computed tomography angiography: A multicenter prospective study

BACKGROUND

There are limited data assessing statin therapy in patients with nonobstructive coronary plaque on coronary computed tomography angiography (CCTA).

METHODS

Two hundred six consecutive patients with mild noncalcified plaque on CCTA were enrolled in this multicenter prospective observational study. Subjects were divided into 3 groups according to subsequent statin therapy: intensive statin therapy (n = 55), moderate statins (n = 85), and no statin (n = 66). Serial scans were performed after a median interval of 18 months. Low-attenuation plaque (LAP) volume, total plaque volume, and percent plaque volume were measured.

RESULTS

The LAP volume, total plaque volume, and percent plaque volume showed significant regression among intensive-statin compared with no-statin group (annualized changes: -7.1 ± 13.1 vs 0.9 ± 12.7 mm(3), P< .001; -16.4 ± 35.0 vs 12.3 ± 32.4 mm(3), P< .001; and -6.2% ± 11.8% vs 3.5% ± 12.1%, P< .001, respectively). Progression of LAP volume, total plaque volume, and percent plaque volume was retarded among moderate-statin compared with no-statin group (annualized changes: -2.8 ± 7.6 vs 0.9 ± 12.7 mm(3), P= .041; -0.1 ± 25.6 vs 12.3 ± 32.4 mm(3), P= .014; and -1.8% ± 11.2% vs 3.5% ± 12.1%, P= .006, respectively). On multivariable model predicting change in total plaque volume, higher baseline LAP volume, moderate statin therapy, and intensive statin therapy were each independent predictors of plaque regression (standardized coefficients: baseline LAP volume -0.36, P< .001; moderate statin -0.21, P= .004; intensive statin -0.36, P< .001, respectively).

CONCLUSIONS

This study suggests that statin treatment can retard progression and even induce regression of mild noncalcified coronary plaque. Patients with greater baseline LAP volume are more likely to benefit from statin therapy.

Coronary atheroma progression rates in men and women following high-intensity statin therapy: A pooled analysis of REVERSAL, ASTEROID and SATURN

BACKGROUND AND AIMS

High-intensity statin therapy (HIST) reduces cardiovascular events, however, sex-related differences in treatment effects are not well characterized.

METHODS

A patient-level post hoc pooled analysis of 3 randomized trials utilizing serial coronary intravascular ultrasound was undertaken, testing the anti-atherosclerotic effects of HIST in coronary disease patients. Sex-related differences in changes (Δ) in coronary percent atheroma volume (PAV) were ascertained following 18-24 months of HIST (atorvastatin 80 mg or rosuvastatin 40 mg daily), and further characterized according to on-treatment lipid and lipoprotein levels.

RESULTS

In women (n = 451) compared with men (n = 1190), on-treatment levels of LDL-C (68 ± 24 vs. 67 ± 22 mg/dl, p=0.62) and apoB (77 ± 23 vs. 76 ± 20 mg/dL, p=0.51) were similar; levels of HDL-C (53 ± 12 vs. 47 ± 11 mg/dl, p < 0.001), apoA1 (154 ± 26 vs. 140 ± 24 mg/dl, p < 0.001), triglycerides [122 (95, 158) vs. 114 (89, 154) mg/dl, p=0.012] and CRP [1.7 (0.9, 3.8) vs. 1.1 (0.6, 2.7) mg/l, p < 0.001] were higher; while the total cholesterol/HDL-C (TC/HDL-C) ratio was lower (2.9 ± 0.8 vs. 3.1 ± 0.8, p < 0.001). Compared with men, women harbored significantly lower baseline PAV (34.8 ± 8.7 vs. 38.3 ± 8.8%, p < 0.001), yet demonstrated significantly greater PAV regression (ΔPAV -1.07 ± 0.26 vs. -0.66 ± 0.23%, p=0.02). When achieved on-treatment levels of LDL-C were <64 mg/dl, apoB <73 mg/dl, non-HDL-C <88.8 mg/dl, and TC/HDL-C <2.99, women demonstrated significantly greater PAV regression than men. Multivariable analysis revealed female sex to independently associate with PAV regression (coefficient -0.66, p=0.02).

CONCLUSIONS

Women demonstrate greater degrees of coronary plaque regression compared with men following long-term HIST, especially in the setting of lower achieved atherogenic lipoprotein levels.

Remarkable regression of coronary atherosclerosis: An interplay of pharmacotherapeutic and lifestyle factors

Coronary heart disease is the leading cause of death in the world today. Regression of coronary atherosclerosis using a combination of drugs and lifestyle interventions has been reported. This letter describes three patients with remarkable reduction in angiographic stenosis of coronary arteries that is generally not considered feasible.

Regression of coronary atheroma with statin therapy

PURPOSE OF REVIEW

This article reviews coronary atheroma regression with statin therapy.

RECENT FINDINGS

Unlocking the mechanisms of atherogenesis and plaque progression has been fundamental to understanding the means by which contemporary antiatherosclerotic therapies lower cardiovascular risk. The advent of intracoronary imaging has helped chart the natural course of coronary atherosclerosis and evaluate therapeutic strategies that modify its natural progression. From earlier intravascular ultrasonography studies using lower dose statins to recent clinical trials evaluating the long-term effects of high-intensity statin therapies, our understanding of the relationship between incremental low-density lipoprotein-cholesterol lowering and coronary atheroma progression-regression has evolved considerably, particularly in patients of varying cardiometabolic risk including those with diabetes mellitus and acute coronary syndromes. Evaluating the impact of novel therapies on coronary atheroma using imaging will continue to be integral in establishing their mechanistic benefit prior to embarking on large-scale, expensive, long-duration randomized trials powered for clinical end points.

SUMMARY

Statins have remarkably impacted the natural course of coronary atherogenesis. Intravascular imaging has proven crucial in evaluating the mechanisms by which we can curb coronary atheroma progression and induce its regression. The insights gleaned from intravascular imaging trials evaluating statins have been complementary to the findings from large-scale trials powered for clinical end points.

Efficacy of Statin Therapy in Inducing Coronary Plaque Regression in Patients with Low Baseline Cholesterol Levels

Aim: The efficacy of statin therapy in inducing coronary plaque regression may depend on baseline cholesterol levels. We aimed to determine the efficacy of statin therapy in inducing coronary plaque regression in statin-naïve patients with low cholesterol levels using serial intravascular ultrasound (IVUS) data from the treatment with statin on atheroma regression evaluated by virtual histology IVUS (TRUTH) study.

Methods: The TRUTH study is a prospective, multicenter trial, comparing the efficacies of pitavastatin and pravastatin in coronary plaque regression in 164 patients. All patients were statin-naïve and received statin therapy only after study enrollment. The primary endpoint was the observation of coronary plaque progression, despite statin therapy.

Results: Serial IVUS data, at baseline and after an 8-month follow-up, were available for 119 patients. The patients were divided into three groups based on non-high-density lipoprotein cholesterol (HDL-C) levels—low: ≤ 140 mg/dl, n = 38; moderate: 141–169 mg/dl, n = 42; and high: ≥ 170 mg/dl, n = 39. Coronary plaque progression was noted in the low cholesterol group, whereas plaque regression was noted in the moderate and high cholesterol groups [%Δplaque volume: 2.3 ± 7.4 vs. − 2.7 ± 10.7 vs. − 3.2 ± 7.5, p = 0.004 (analysis of variance)]. After adjusting for all variables, a low non-HDLC level (≤ 140 mg/dl) was identified as an independent predictor of coronary plaque progression [odds ratio, 3.7; 95% confidence interval, 1.5–9.1, p = 0.004].

Conclusion: Serial IVUS data analysis indicated that statin therapy was less effective in inducing coronary plaque regression in patients with low cholesterol levels but more effective in those with high cholesterol levels at baseline.

University Hospital Medical Information Network (UMIN) (UMIN ID: C000000311).

Effect of the BET Protein Inhibitor, RVX-208, on Progression of Coronary Atherosclerosis: Results of the Phase 2b, Randomized, Double-Blind, Multicenter, ASSURE Trial

BACKGROUND

Bromodomain and extra-terminal (BET) proteins regulate transcription of lipoprotein and inflammatory factors implicated in atherosclerosis. The impact of BET inhibition on atherosclerosis progression is unknown.

METHODS

ASSURE was a double-blind, randomized, multicenter trial in which 323 patients with angiographic coronary disease and low high-density lipoprotein cholesterol (HDL-C) levels were randomized in a 3:1 fashion to treatment with the BET protein inhibitor RVX-208 200 mg or placebo for 26 weeks. Plaque progression was measured with serial intravascular ultrasound imaging. Lipid levels, safety, and tolerability were also assessed.

RESULTS

During treatment, apolipoprotein (apo)A-I increased by 10.6% with placebo (P < 0.001 compared with baseline) and 12.8% with RVX-208 (P < 0.001 compared with baseline), between groups P = 0.18. HDL-C increased by 9.1% with placebo (P < 0.001 compared with baseline) and 11.1% with RVX-208 (P < 0.001 compared with baseline), between groups P = 0.24. Low-density lipoprotein cholesterol (LDL-C) decreased by 17.9% with placebo (P < 0.001 compared with baseline) and 15.8% with RVX-208 (P < 0.001 compared with baseline), between groups P = 0.55. The primary endpoint, the change in percent atheroma volume, decreased 0.30% in placebo-treated patients (P = 0.23 compared with baseline) and 0.40% in the RVX-208 group (P = 0.08 compared with baseline), between groups P = 0.81. Total atheroma volume decreased 3.8 mm(3) in the placebo group (P = 0.01 compared with baseline) and 4.2 mm(3) in the RVX-208 group (P < 0.001 compared with baseline), P = 0.86 between groups. A greater incidence of elevated liver enzymes was observed in RVX-208-treated patients (7.1 vs. 0%, P = 0.009).

CONCLUSION

Administration of the BET protein inhibitor RVX-208 showed no greater increase in apoA-I or HDL-C or incremental regression of atherosclerosis than administration of placebo.

TRIAL REGISTRATION

ClinicalTrials.gov identifier-NCT01067820.

Impact of the Everolimus-eluting Bioresorbable Scaffold in Coronary Atherosclerosis

INTRODUCTION AND OBJECTIVES

The Absorb bioresorbable vascular scaffold has been shown to decrease total plaque areas in the treated segment. However, it is unknown whether plaque size is modified in scaffolded segments only or whether the modification extends to other coronary segments.

METHODS

Absorb Cohort A is a single-arm, prospective study, with safety and imaging endpoints, in which 30 patients underwent percutaneous coronary intervention with the first generation Absorb bioresorbable vascular scaffold. Noninvasive multislice computed tomography imaging was performed in 18 patients at 18 months and 5 years of follow-up. The present study was an intrapatient comparison of matched segments (normalized by the segment length) of the scaffolded region with nonintervened segments for lumen volume, vessel volume, plaque volume, plaque burden, and percent change in plaque atheroma volume.

RESULTS

All 18 scaffolded segments could be analyzed. In the nonintervened segments, 1 of 72 segments had a motion artifact and was excluded. Serial comparison showed that the scaffolded segments showed no significant change in the mean plaque burden, total atheroma volume, total lumen volume, or vessel volume between 18 months and 5 years. Conversely, the untreated segments showed a significant increase in plaque burden (2.7 ± 6.5%; P < .01) and normalized plaque volumes (8.0 ± 22.8mm(3); P < .01). This resulted in a significant difference in plaque burden between scaffolded and nonintervened segments (P = .03).

CONCLUSIONS

In this small series, the Absorb bioresorbable vascular scaffold showed the potential to provide an additional benefit to pharmacological therapy in locally reducing progression of percent plaque burden. These findings need to be confirmed in larger studies.

Statin-induced coronary artery disease regression rates differ in men and women

PURPOSE OF REVIEW

Whether statins are equi-efficacious in women and men continues to be debated. The potential antiatherosclerotic effects of high-intensity statin therapy on coronary atheroma in women compared with men have only very recently been characterized. This review aims to summarize the evidence underlying these recent observations.

RECENT FINDINGS

Coronary intravascular ultrasound (IVUS) is a highly sensitive plaque imaging tool, and serial changes of plaque burden on IVUS are known to associate with incident cardiovascular events. Study of coronary atheroma by intravascular ultrasound: effect of rosuvastatin versus atorvastatin was a randomized controlled trial employing serial IVUS to evaluate the antiatherosclerotic efficacy of high-dose rosuvastatin and atorvastatin during a 24-month study period. Study of coronary atheroma by intravascular ultrasound: effect of rosuvastatin versus atorvastatin revealed significantly greater coronary atheroma regression in women compared with men, particularly in the setting of lower achieved LDL cholesterol. Results of this analysis also identified a significant interaction between sex and type of statin used.

SUMMARY

These findings support the broad use of statins, especially high-intensity statins, in women with coronary artery disease, who may in fact derive greater benefit than men. These findings also suggest the need for dedicated clinical trials involving women, supporting the notion of more personalized therapeutic strategies for tackling atherosclerotic disease.