A critical appreciation of pathway analysis in atherosclerotic disease. Cellular phenotypic plasticity as an illustrative example

The rapid advancements in genome-scale (omics) techniques has created significant opportunities to investigate complex disease mechanisms in tissues and cells. Nevertheless, interpreting -omics data can be challenging, and pathway enrichment analysis is a frequently used method to identify candidate molecular pathways that drive gene expression changes. With a growing number of -omics studies dedicated to atherosclerosis, there has been a significant increase in studies and hypotheses relying on enrichment analysis. This brief review discusses the benefits and limitations of pathway enrichment analysis within atherosclerosis research. We highlight the challenges of identifying complex biological processes, such as cell phenotypic switching, within -omics data. Additionally, we emphasize the need for more comprehensive and curated gene sets that reflect the biological complexity of atherosclerosis. Pathway enrichment analysis is a valuable tool for gaining insights into the molecular mechanisms of atherosclerosis. Nevertheless, it is crucial to remain aware of the intrinsic limitations of this approach. By addressing these weaknesses, enrichment analysis in atherosclerosis can lead to breakthroughs in identifying the mechanisms of disease progresses, the identification of key driver genes, and consequently, advance personalized patient care.

Microvascular endothelial dysfunction in skin is associated with higher risk of heart failure with preserved ejection fraction in women with type 2 diabetes: the Hoorn Diabetes Care System Cohort

BACKGROUND

Microvascular dysfunction plays a crucial role in complications of type 2 diabetes and might contribute to heart failure with preserved ejection fraction (HFpEF), a disease that disproportionally affects women. We aimed to investigate if presence and degree of microvascular dysfunction (MVD) in skin relates to markers of left ventricular diastolic dysfunction (LVDD) and HFpEF risk in adults with type 2 diabetes, and whether sex modifies this association.

METHODS

We recruited 154 participants (50% women) from the Hoorn Diabetes Care System Cohort, a prospective cohort study, for in vivo evaluation of skin MVD, echocardiography and blood sampling. MVD was assessed by laser speckle contrast analysis combined with iontophoresis of insulin, acetylcholine and sodium nitroprusside (SNP). We performed a cross-sectional analysis of the association between perfusion responses and echocardiographic and clinical markers of LVDD and the H2FPEF score by multivariable linear regression analysis adjusted for confounders. Sex was evaluated as a potential effect modifier and the analysis was stratified.

RESULTS

Mean age was 67 ± 6y, mean HbA1c 7.6 ± 1.3%. Women were more frequently obese (54.5 vs. 35.1%), had higher NT-proBNP plasma levels (80, IQR:34-165 vs. 46, 27-117 pg/ml) and E/E'(13.3 ± 4.3 vs. 11.4 ± 3.0) than men. Eleven women and three men were diagnosed with HFpEF, and showed lower perfusion response to insulin than those without HFpEF. A lower perfusion response to insulin and acetylcholine was associated with higher HFpEF risk in women, but not men (10% decreased perfusion response was associated with 5.8% [95%CI: 2.3;9.4%] and 5.9% [1.7;10.1%] increase of the H2FPEF score, respectively). A lower perfusion response to SNP was associated with higher pulmonary arterial systolic pressure in men while a lower perfusion response to acetylcholine associated with higher LV mass index in women and with worse LV longitudinal strain in the total population. No significant associations were found between perfusion responses and conventional LVDD markers.

CONCLUSIONS

Impaired microvascular responses to insulin and acetylcholine in skin confers a higher risk of HFpEF in women with type 2 diabetes. In vivo measures of systemic MVD could represent novel risk markers for HFpEF, opening new avenues for the prevention of HFpEF in type 2 diabetes.

Design and rationale of the NetherLands registry of invasive Coronary vasomotor Function Testing (NL-CFT)

BACKGROUND

Angina without angiographic evidence of obstructive coronary artery disease (ANOCA) is a highly prevalent condition with insufficient pathophysiological knowledge and lack of evidence-based medical therapies. This affects ANOCA patients prognosis, their healthcare utilization and quality of life. In current guidelines, performing a coronary function test (CFT) is recommended to identify a specific vasomotor dysfunction endotype. The NetherLands registry of invasive Coronary vasomotor Function testing (NL-CFT) has been designed to collect data on ANOCA patients undergoing CFT in the Netherlands.

METHODS

The NL-CFT is a web-based, prospective, observational registry including all consecutive ANOCA patients undergoing clinically indicated CFT in participating centers throughout the Netherlands. Data on medical history, procedural data and (patient reported) outcomes are gathered. The implementation of a common CFT protocol in all participating hospitals promotes an equal diagnostic strategy and ensures representation of the entire ANOCA population. A CFT is performed after ruling out obstructive coronary artery disease. It comprises of both acetylcholine vasoreactivity testing as well as bolus thermodilution assessment of microvascular function. Optionally, continuous thermodilution or Doppler flow measurements can be performed. Participating centers can perform research using own data, or pooled data will be made available upon specific request via a secure digital research environment, after approval of a steering committee.

CONCLUSION

NL-CFT will be an important registry by enabling both observational and registry based (randomized) clinical trials in ANOCA patients undergoing CFT.

Diastolic dysfunction and sex-specific progression to HFpEF: current gaps in knowledge and future directions

Diastolic dysfunction of the left ventricle (LVDD) is equally common in elderly women and men. LVDD is a condition that can remain latent for a long time but is also held responsible for elevated left ventricular filling pressures and high pulmonary pressures that may result in (exercise-induced) shortness of breath. This symptom is the hallmark of heart failure with preserved ejection fraction (HFpEF) which is predominantly found in women as compared to men within the HF spectrum. Given the mechanistic role of LVDD in the development of HFpEF, we review risk factors and mechanisms that may be responsible for this sex-specific progression of LVDD towards HFpEF from an epidemiological point-of-view and propose future research directions.

Mortality after hospital admission for heart failure: improvement over time, equally strong in women as in men

Background

To assess the trend in age- and sex-stratified mortality after hospitalization for heart failure (HF) in the Netherlands.

Methods

Two nationwide cohorts of patients, hospitalized for new onset heart failure between 01.01.2000–31.12.2002 and between 01.01.2008–31.12.2010, were constructed by linkage of the Dutch Hospital Discharge Registry and the National Cause of Death registry. 30-day, 1-year and 5 -year overall and cause-specific mortality rates stratified by age and sex were assessed and compared over time.

Results

We identified 40,230 men and 41,582 women. In both cohorts, men were on average younger than women (74–75 and 78–79 years, respectively) and more often had comorbid conditions (37 and 30%, respectively). In the 2008–10 cohort, mortality rates for men were 13, 32 and 64% for respectively 30-day, 1-year and 5-year mortality and 14, 33 and 66% for women. Mortality rates increased considerably with age similarly in men and women (e.g. from 10.5% in women aged 25–54 to 46.1% in those aged 85 and older after 1 year). Between the two time periods, mortality rates dropped across all ages, equally strong in women as in men. The 1-year absolute risk of death declined by 4.0% (from 36.1 to 32.1%) in men and 3.2% (from 36.2 to 33.0%) in women.

Conclusions

Mortality after hospitalization for new onset HF remains high, however, both short-term and long-term survival is improving over time. This improvement was similar across all ages and equally strong in women as in men.

Meta-analysis of the outcomes of treatment of internal carotid artery near occlusion

Background

Guidelines recommend treating patients with an internal carotid artery near occlusion (ICANO) with best medical therapy (BMT) based on weak evidence. Consequently, patients with ICANO were excluded from randomized trials. The aim of this individual‐patient data (IPD) meta‐analysis was to determine the optimal treatment approach.

Methods

A systematic search was performed in MEDLINE, EMBASE and the Cochrane Library databases in January 2018. The primary outcome was the occurrence of any stroke or death within the first 30 days of treatment, analysed by multivariable mixed‐effect logistic regression. The secondary outcome was the occurrence of any stroke or death beyond 30 days up to 1 year after treatment, evaluated by Kaplan–Meier survival analysis.

Results

The search yielded 1526 articles, of which 61 were retrieved for full‐text review. Some 32 studies met the inclusion criteria and pooled IPD were available from 11 studies, including some 703 patients with ICANO. Within 30 days, any stroke or death was reported in six patients (1·8 per cent) in the carotid endarterectomy (CEA) group, five (2·2 per cent) in the carotid artery stenting (CAS) group and seven (4·9 per cent) in the BMT group. This resulted in a higher 30‐day stroke or death rate after BMT than after CEA (odds ratio 5·63, 95 per cent c.i. 1·30 to 24·45; P = 0·021). No differences were found between CEA and CAS. The 1‐year any stroke‐ or death‐free survival rate was 96·1 per cent for CEA, 94·4 per cent for CAS and 81·2 per cent for BMT.

Conclusion

These data suggest that BMT alone is not superior to CEA or CAS with respect to 30‐day or 1‐year stroke or death prevention in patients with ICANO. These patients do not appear to constitute a high‐risk group for surgery, and consideration should made to including them in future RCTs of internal carotid artery interventions.

Enhancing cardiovascular artificial intelligence (AI) research in the Netherlands: CVON-AI consortium

Background

Machine learning (ML) allows the exploration and progressive improvement of very complex high-dimensional data patterns that can be utilised to optimise specific classification and prediction tasks, outperforming traditional statistical approaches. An enormous acceleration of ready-to-use tools and artificial intelligence (AI) applications, shaped by the emergence, refinement, and application of powerful ML algorithms in several areas of knowledge, is ongoing. Although such progress has begun to permeate the medical sciences and clinical medicine, implementation in cardiovascular medicine and research is still in its infancy.

Objectives

To lay out the theoretical framework, purpose, and structure of a novel AI consortium.

Methods

We have established a new Dutch research consortium, the CVON-AI, supported by the Netherlands Heart Foundation, to catalyse and facilitate the development and utilisation of AI solutions for existing and emerging cardiovascular research initiatives and to raise AI awareness in the cardiovascular research community. CVON-AI will connect to previously established CVON consortia and apply a cloud-based AI platform to supplement their planned traditional data-analysis approach.

Results

A pilot experiment on the CVON-AI cloud was conducted using cardiac magnetic resonance data. It demonstrated the feasibility of the platform and documented excellent correlation between AI-generated ventricular function estimates as compared to expert manual annotations. The resulting AI solution was then integrated in a web application.

Conclusion

CVON-AI is a new consortium meant to facilitate the implementation and raise awareness of AI in cardiovascular research in the Netherlands. CVON-AI will create an accessible cloud-based platform for cardiovascular researchers, demonstrate the clinical applicability of AI, optimise the analytical methodology of other ongoing CVON consortia, and promote AI awareness through education and training.

Cardiovascular and all-cause mortality in patients with intermittent claudication and critical limb ischaemia

BACKGROUND

The aim of this study was to evaluate absolute mortality risks and to determine whether changes in mortality risk occurred in patients with intermittent claudication (IC) or critical limb ischaemia (CLI) in the Netherlands between 1998 and 2010.

METHODS

Data for patients treated between 1998 and 2010 were obtained from Dutch nationwide registers: the Hospital Discharge Register, Population Register and Cause of Death Register. The registers were used to obtain information regarding IC and CLI hospitalizations, co-morbidities, demographic factors, and date and cause of death. The cohort was split into two time intervals for comparison: 1998-2004 (period 1) and 2005-2010 (period 2). Thirty-day mortality was excluded to eliminate per-admission complications. One- and 5-year cardiovascular and all-cause mortality rates were compared with those of a representative sample of the general Dutch population (28 494 persons) by Cox proportional hazards models.

RESULTS

Some 47 548 patients were included, 34 078 with IC and 13 470 with CLI. In patients with IC, the age-adjusted 5-year mortality risk for cardiovascular disease decreased significantly in period 2 (14·1 per cent) compared with that in period 1 (16·1 per cent) in men only (5-year adjusted hazard ratio (HR) 0·76, 95 per cent c.i. 0·69 to 0·83; P < 0·001). In patients with CLI, the cardiovascular mortality risk decreased significantly only in women, with the 5-year risk reducing from 31·2 per cent in period 1 to 29·2 per cent in period 2 (adjusted HR 0·84, 0·74 to 0·94; P = 0·004). Compared with the general population, the mortality risk in patients with IC was increased between 1·70 (1·58 to 1·83) and 3·20 (2·69 to 3·81) times, and in those with CLI the risk was increased between 2·24 (2·09 to 2·40) and 5·19 (4·30 to 6·26) times.

CONCLUSION

The risk of premature death in patients with IC and CLI declined significantly in the Netherlands, in a sex-specific manner, over the period from 1998 to 2010. The absolute risk of cardiovascular mortality remains high in these patients.

Optimization of large animal MI models; a systematic analysis of control groups from preclinical studies

Large animal models are essential for the development of novel therapeutics for myocardial infarction. To optimize translation, we need to assess the effect of experimental design on disease outcome and model experimental design to resemble the clinical course of MI. The aim of this study is therefore to systematically investigate how experimental decisions affect outcome measurements in large animal MI models. We used control animal-data from two independent meta-analyses of large animal MI models. All variables of interest were pre-defined. We performed univariable and multivariable meta-regression to analyze whether these variables influenced infarct size and ejection fraction. Our analyses incorporated 246 relevant studies. Multivariable meta-regression revealed that infarct size and cardiac function were influenced independently by choice of species, sex, co-medication, occlusion type, occluded vessel, quantification method, ischemia duration and follow-up duration. We provide strong systematic evidence that commonly used endpoints significantly depend on study design and biological variation. This makes direct comparison of different study-results difficult and calls for standardized models. Researchers should take this into account when designing large animal studies to most closely mimic the clinical course of MI and enable translational success.

Meta-analysis of the costs of carotid artery stenting and carotid endarterectomy

BACKGROUND

Carotid artery stenting (CAS) is currently associated with an increased risk of 30-day stroke compared with carotid endarterectomy (CEA), whereas both interventions seem equally durable beyond the periprocedural period. Although the clinical outcomes continue to be scrutinized, there are few data summarizing the costs of both techniques.

METHODS

A systematic search was conducted in MEDLINE, Embase and Cochrane databases in August 2016 identifying articles comparing the costs or cost-effectiveness of CAS and CEA in patients with carotid artery stenosis. Combined overall effect sizes were calculated using random-effects models. The in-hospital costs were specified to gain insight into the main heads of expenditure associated with both procedures.

RESULTS

The literature search identified 617 unique articles, of which five RCTs and 12 cohort studies were eligible for analysis. Costs of the index hospital admission were similar for CAS and CEA. Costs of the procedure itself were 51 per cent higher for CAS, mainly driven by the higher costs of devices and supplies, but were balanced by higher postprocedural costs of CEA. Long-term cost analysis revealed no difference in costs or quality of life after 1 year of follow-up.

CONCLUSION

Hospitalization and long-term costs of CAS and CEA appear similar. Economic considerations should not influence the choice of stenting or surgery in patients with carotid artery stenosis being considered for revascularization.

Time-dependent trends in cardiovascular adverse events during follow-up after carotid or iliofemoral endarterectomy

BACKGROUND

Recent observations have suggested a decline in vulnerable carotid artery and iliofemoral atherosclerotic plaque characteristics over the past decade. The aim of this study was to determine whether, in the presence of clinically manifest carotid or peripheral artery disease, secondary adverse cardiovascular events decreased over this period.

METHODS

Patients included in the Athero-Express biobank between 2003 and 2012 were analysed. During 3-year follow-up, composite cardiovascular endpoints were documented yearly, including: myocardial infarction, coronary interventions, stroke, peripheral interventions and cardiovascular death. The major cardiovascular endpoint consisted of myocardial infarction, stroke and cardiovascular death.

RESULTS

Some 1684 patients who underwent carotid endarterectomy (CEA) and another 530 who had iliofemoral endarterectomy (IFE) were analysed. In total, 405 (25·2 per cent) and 236 (45·9 per cent) patients had a composite cardiovascular endpoint within 3 years after CEA and IFE respectively. Corrected for possible confounders, the percentage of patients with a secondary cardiovascular event after CEA did not change over time (hazard ratio (HR) 0·91, 95 per cent c.i. 0·65 to 1·28; P = 0·590, for 2011-2012 versus 2003-2004). In patients who had IFE, the incidence of secondary cardiovascular events significantly decreased only in the last 2 years (HR 0·62, 0·41 to 0·94; P = 0·024), owing to a decrease in peripheral (re)interventions in 2011-2012 (HR 0·59, 0·37 to 0·94; P = 0·028). No decrease in major cardiovascular events was observed in either group.

CONCLUSION

In patients who had undergone either CEA or IFE there was no evidence of a decrease in all secondary cardiovascular events. There were no differences in major cardiovascular events.

High On-Treatment Platelet Reactivity in Peripheral Arterial Disease: A Pilot Study to Find the Optimal Test and Cut Off Values

OBJECTIVE

Restenosis and stent thrombosis after endovascular intervention in patients with peripheral arterial disease (PAD) can potentially be tackled by more intensive antiplatelet therapy, such as dual antiplatelet therapy (DAPT) consisting of aspirin and P2Y12 inhibitor. Despite clopidogrel treatment, some patients still display high platelet reactivity (HCPR). Tailored antiplatelet therapy, based on platelet reactivity testing, might overcome HCPR. However, more data are warranted regarding the proportion of patients with HCPR in the PAD population, different platelet reactivity tests, their correlation, and the optimal timing for these tests as a stepping stone for a future trial investigating the potential benefit of tailored antiplatelet therapy in PAD patients.

METHODS

Thirty patients on DAPT after percutaneous transluminal angioplasty underwent platelet reactivity testing by VerifyNow, vasodilator-stimulated phosphoprotein (VASP) and platelet activation assay, and CYP2C19-polymorphism testing.

RESULTS

The proportion of patients with HCPR measured by VerifyNow varied between 43.3% and 83.3%, depending on the cut off values used. Testing within 24 hours of initiation of DAPT gave a higher proportion of HCPR than testing after more than 24 hours. According to DNA testing, 14.8% were CYP2C19*2 homozygote, 22.2% heterozygote, and 63% CYP2C19*2 negative. VASP assay revealed 24% HCPR. The highest HCPR rate was found with a VerifyNow cut off of less than 40% inhibition, whereas the lowest HCPR rate was found with the VASP assay. There was a low correlation between the tests.

CONCLUSION

HCPR is present in PAD patients and research on HCPR is needed in this population; timing of tests is relevant and standardisation of tests is needed. The optimal conditions for platelet function testing should be determined.

Management of extracranial carotid artery aneurysm

INTRODUCTION

Aneurysms of the extracranial carotid artery (ECAA) are rare. Several treatments have been developed over the last 20 years, yet the preferred method to treat ECAA remains unknown. This paper is a review of all available literature on the risk of complications and long-term outcome after conservative or invasive treatment of patients with ECAA.

METHODS

Reports on ECAA treatment until July 2014 were searched in PubMed and Embase using the key words aneurysm, carotid, extracranial, and therapy.

RESULTS

A total of 281 articles were identified. Selected articles were case reports (n = 179) or case series (n = 102). Papers with fewer than 10 patients were excluded, resulting in the final selection of 39 articles covering a total of 1,239 patients. Treatment consisted of either conservative treatment in 11% of the cases or invasive treatment in 89% of the cases. Invasive treatment comprised surgery in 94%, endovascular approach in 5%, and a hybrid approach in 1% of the patients. The most common complication described after invasive therapy was cranial nerve damage, which occurred in 11.8% of patients after surgery. The 30 day mortality rate and stroke rate in conservatively treated patients was 4.67% and 6.67%, after surgery 1.91% and 5.16%. Information on confounders in the present study was incomplete. Therefore, adjustments to correct for confounding by indication could not be done.

CONCLUSIONS

This review summarizes the largest available series in the literature on ECAA management. The number of ECAAs reported in current literature is scarce. The early and long-term outcome of invasive treatment in ECAA is favorable; however, cranial nerve damage after surgery occurs frequently. Unfortunately, due to limitations in reporting of results and confounding by indication in the available literature, it was not possible to determine the optimal treatment strategy. There is a need for a multicenter international registry to reveal the optimal treatment for ECAA.

Vascular age to determine cardiovascular disease risk: A systematic review of its concepts, definitions, and clinical applications

BACKGROUND

Vascular age is an alternate means of representing an individual's cardiovascular risk. Little consensus exists on what vascular age represents and its clinical utility has not been determined. We systematically reviewed the literature to provide a comprehensive overview of different methods that have been used to define vascular age, and to examine its potential clinical value in patient communication and risk prediction.

DESIGN

This was a systematic review with data sources of PubMed and Embase.

RESULTS

We identified 39 articles on vascular age, 20 proposed to use vascular age as a communication tool and 19 proposed to use vascular age as a means to improve cardiovascular risk prediction. Eight papers were methodological and 31 papers reported on vascular age in study populations. Of these 31 papers, vascular age was a direct translation of the absolute risk estimated by existing cardiovascular risk prediction models in 15 papers, 12 derived vascular age from the reference values of an additional test, and in three papers vascular age was defined as the age at which the estimated cardiovascular risk equals the risk from non-invasive imaging observed degree of atherosclerosis. One trial found a small effect on risk factor levels when vascular age was communicated instead of cardiovascular risk.

CONCLUSION

Despite sharing a common name, various studies have proposed distinct ways to define and measure vascular age. Studies into the effects of vascular age as a tool to improve cardiovascular risk prediction or patient communication are scarce but will be required before its clinical use can be justified.

Common carotid intima-media thickness does not add to Framingham risk score in individuals with diabetes mellitus: the USE-IMT initiative

AIMS/HYPOTHESIS

The aim of this work was to investigate whether measurement of the mean common carotid intima-media thickness (CIMT) improves cardiovascular risk prediction in individuals with diabetes.

METHODS

We performed a subanalysis among 4,220 individuals with diabetes in a large ongoing individual participant data meta-analysis involving 56,194 subjects from 17 population-based cohorts worldwide. We first refitted the risk factors of the Framingham heart risk score on the individuals without previous cardiovascular disease (baseline model) and then expanded this model with the mean common CIMT (CIMT model). The absolute 10 year risk for developing a myocardial infarction or stroke was estimated from both models. In individuals with diabetes we compared discrimination and calibration of the two models. Reclassification of individuals with diabetes was based on allocation to another cardiovascular risk category when mean common CIMT was added.

RESULTS

During a median follow-up of 8.7 years, 684 first-time cardiovascular events occurred among the population with diabetes. The C statistic was 0.67 for the Framingham model and 0.68 for the CIMT model. The absolute 10 year risk for developing a myocardial infarction or stroke was 16% in both models. There was no net reclassification improvement with the addition of mean common CIMT (1.7%; 95% CI -1.8, 3.8). There were no differences in the results between men and women.

CONCLUSIONS/INTERPRETATION

There is no improvement in risk prediction in individuals with diabetes when measurement of the mean common CIMT is added to the Framingham risk score. Therefore, this measurement is not recommended for improving individual cardiovascular risk stratification in individuals with diabetes.

Increased age, high body mass index and low HDL-C levels are related to an echolucent carotid intima-media: the METEOR study

INTRODUCTION

Echolucent plaques are related to a higher cardiovascular risk. Studies to investigate the relationship between echolucency and cardiovascular risk in the early stages of atherosclerosis are limited. We studied the relationship between cardiovascular risk factors and echolucency of the carotid intima-media in low-risk individuals.

METHODS

Data were analysed from the Measuring Effects on Intima-Media Thickness: an Evaluation of Rosuvastatin (METEOR) study, a randomized placebo-controlled trial including 984 individuals which showed that rosuvastatin attenuated the rate of change of carotid intima-media thickness (CIMT). In this post hoc analysis, duplicate baseline ultrasound images from the far wall of the left and right common carotid arteries were used for the evaluation of the echolucency of the carotid intima-media, measured by grey-scale median (GSM) on a scale of 0-256. Low GSM values reflect echolucent, whereas high values reflect echogenic structures. The relationship between baseline GSM and cardiovascular risk factors was evaluated using linear regression models.

RESULTS

Mean baseline GSM (± SD) was 84 ± 29. Lower GSM of the carotid intima-media was associated with older age, high body mass index (BMI) and low levels of high-density lipoprotein cholesterol (HDL-C) [beta -4.49, 95% confidence interval (CI) -6.50 to -2.49; beta -4.51, 95% CI -6.43 to -2.60; beta 2.45, 95% CI 0.47 to 4.42, respectively]. Common CIMT was inversely related to GSM of the carotid intima-media (beta -3.94, 95% CI -1.98 to -5.89).

CONCLUSION

Older age, high BMI and low levels of HDL-C are related to echolucency of the carotid intima-media. Hence, echolucency of the carotid intima-media may be used as a marker of cardiovascular risk profile to provide more information than thickness alone.

Manual or semi-automated edge detection of the maximal far wall common carotid intima-media thickness: a direct comparison

BACKGROUND

Automated edge detection is thought to be superior to manual edge detection in quantification of the far wall common carotid intima-media thickness (CIMT), yet published evidence making a direct comparison is not available.

METHODS

Data were used from the METEOR study, a randomized placebo-controlled trial among 984 individuals showing that rosuvastatin attenuated the rate of change of 2 year change in CIMT among low-risk individuals with subclinical atherosclerosis. For this post hoc analysis, CIMT images of the far wall of the common carotid artery were evaluated using manual and semi-automated edge detection and reproducibility, relation to cardiovascular risk factors, rates of change over time and effects of lipid-lowering therapy were assessed.

RESULTS

Reproducibility was high for both reading methods. Direction, magnitude and statistical significance of risk factor relations were similar across methods. Rate of change in CIMT in participants assigned to placebo was 0.0066 mm per year (SE: 0.0027) for manually and 0.0072 mm per year (SE: 0.0029) for semi-automatically read images. The effect of lipid-lowering therapy on CIMT changes was -0.0103 mm per year (SE: 0.0032) for manual reading and -0.0111 mm per year (SE: 0.0034) for semi-automated reading.

CONCLUSION

Manual and semi-automated readings of the maximal far wall of the common CIMT images both result in high reproducibility, show similar risk factor relations, rates of change and treatment effects. Hence, choices between semi-automated and manual reading software for CIMT studies likely should be based on logistical and cost considerations rather than differences in expected data quality when the choice is made to use far wall common CIMT measurements.