Association of Intima-Media Thickness Measured at the Common Carotid Artery With Incident Carotid Plaque: Individual Participant Data Meta-Analysis of 20 Prospective Studies

Background The association between common carotid artery intima-media thickness (CCA-IMT) and incident carotid plaque has not been characterized fully. We therefore aimed to precisely quantify the relationship between CCA-IMT and carotid plaque development. Methods and Results We undertook an individual participant data meta-analysis of 20 prospective studies from the Proof-ATHERO (Prospective Studies of Atherosclerosis) consortium that recorded baseline CCA-IMT and incident carotid plaque involving 21 494 individuals without a history of cardiovascular disease and without preexisting carotid plaque at baseline. Mean baseline age was 56 years (SD, 9 years), 55% were women, and mean baseline CCA-IMT was 0.71 mm (SD, 0.17 mm). Over a median follow-up of 5.9 years (5th-95th percentile, 1.9-19.0 years), 8278 individuals developed first-ever carotid plaque. We combined study-specific odds ratios (ORs) for incident carotid plaque using random-effects meta-analysis. Baseline CCA-IMT was approximately log-linearly associated with the odds of developing carotid plaque. The age-, sex-, and trial arm-adjusted OR for carotid plaque per SD higher baseline CCA-IMT was 1.40 (95% CI, 1.31-1.50; I²=63.9%). The corresponding OR that was further adjusted for ethnicity, smoking, diabetes, body mass index, systolic blood pressure, low- and high-density lipoprotein cholesterol, and lipid-lowering and antihypertensive medication was 1.34 (95% CI, 1.24-1.45; I²=59.4%; 14 studies; 16 297 participants; 6381 incident plaques). We observed no significant effect modification across clinically relevant subgroups. Sensitivity analysis restricted to studies defining plaque as focal thickening yielded a comparable OR (1.38 [95% CI, 1.29-1.47]; I²=57.1%; 14 studies; 17 352 participants; 6991 incident plaques). Conclusions Our large-scale individual participant data meta-analysis demonstrated that CCA-IMT is associated with the long-term risk of developing first-ever carotid plaque, independent of traditional cardiovascular risk factors.

Primary cutaneous interdigitating dendritic cell sarcoma (IDCS): Report of a new case and literature review

Interdigitating dendritic cell sarcoma is a very rare entity in the spectrum of histiocytic and dendritic cell neoplasms that mostly occurs in lymph nodes, generally presenting as solitary lymphadenopathy, but may affect every organ. Among extra nodal sites, cutaneous interdigitating dendritic cell sarcoma is exceedingly rare; to date, only 9 cases have been described in English literature. The mean age at diagnosis was 60 years, with a male-female ratio of 1,5 to 1; clinically, two different modalities of skin presentation have been reported: solitary, represented by a single red-brownish nodular lesion, or diffuse, characterized by multiple nodular lesions in one or more body districts. The extreme rarity of this sarcoma and its morphological similarity to other poorly differentiated tumors may lead to a delay in diagnosis; in particular, cutaneous localization may be difficult to differentiate from follicular dendritic cell sarcoma, Langerhans cell sarcoma, poorly differentiated squamous cell carcinoma and more generally sarcomatoid carcinoma, atypical fibroxanthoma, malignant melanoma and several sarcomas. Immunohistochemistry plays an important role in identifying this rare entity and formulating a correct histological diagnosis, fundamental requirement for choosing the best therapeutic approach. We report herein a further case of an 81-year-old Caucasian woman who presented to the Dermatology Department to remove an asymptomatic skin papule in the left temporal region, clinically diagnosed as dermatofibroma. The overall pathological and immunohistochemical features supported the diagnosis of a malignant dendritic cell tumor, consistent of interdigitating dendritic cell sarcoma.

Sex-specific predictors of PCSK9 levels in a European population: The IMPROVE study

BACKGROUND AND AIMS

Proprotein convertase subtilisin/kexin type 9 (PCSK9) is one of the key regulators of low-density lipoprotein cholesterol plasma levels. Circulating PCSK9, which differs between genders, represents a valid pharmacological target for preventing cardiovascular (CV) events. We aimed to investigate sex-related associations between PCSK9 plasma levels and biochemical and anthropomorphic factors, and familial and personal morbidities, in a large European cohort (n = 3673) of men (47.9%) and women (52.1%).

METHODS

Individuals (aged 54-79 years) free of CV diseases were enrolled in seven centers of five European countries: Finland, France, Italy, the Netherlands, and Sweden. PCSK9 plasma levels were measured by ELISA.

RESULTS

PCSK9 was higher in women than in men. Multiple linear regression analysis showed that latitude, sex, and treatments with statins and fibrates were the strongest predictors of PCSK9 in the whole group. These variables, together with triglycerides and high-density lipoprotein cholesterol, were also associated with PCSK9 in men or women. Mean corpuscular hemoglobin concentration and pack-years were PCSK9 independent predictors in women, whereas hypercholesterolemia and physical activity were independent predictors in men. The associations between PCSK9 and latitude, uric acid, diabetes, hypercholesterolemia and physical activity were significantly different in men and women (p_interaction <0.05 for all).

CONCLUSIONS

Besides confirming the association with lipids in the whole group, our study revealed previously unknown differences in PCSK9 predictors in men and women. These might be taken into account when defining individual risk for CV events and/or for refining PCSK9 lowering treatments.

P6315Effects of chronic heart failure unconventional therapies on endothelial function

Introduction

Endothelial Dysfunction (ED) of peripheral arteries in Chronic Heart Failure (CHF) subjects has been demonstrated.

Purpose

We assessed endothelial function in subjects undergoing unconventional treatments for CHF, namely Heart Transplantation (HTX), continuous-flow Left Ventricular Assist Device implantation (LVAD), and repeated levosimendan infusions (r-LEVO).

Methods

Twenty HTX recipients (median time from HTX 21 months), 20 patients supported with LVAD (median time from implant 39 months), and 20 patients receiving monthly Levosimendan infusions (median time on treatment 28 months) were enrolled and compared to a group of 20 healthy subjects. ED was evaluated with ultrasound assessment of the diameter before and after ischemic stress at the brachial artery level. The difference between the two diameters normalized for the baseline value (Flow Mediated Dilation – FMD) has been used for the analysis. All the patients were stable at the time of FMD assessment, with those on r-LEVO being evaluated prior to infusion.

Results

FMD was significantly lower in HTX and LVAD groups with respect to controls (9.8±7.4, 9.3±5.7, and 15.6±6.4% respectively, p=0.01), but not in r-LEVO group (12.5±6.9%).

When patients were analyzed according to time from the operation or on treatment, (< versus > of the median value), no differences were seen in HTX and r-LEVO group, while in LVAD group FMD was borderline significantly higher in patients with longer follow-up (8.4±6.4% versus 10.2±5.2%, p=0.05).

Conclusions

Based on this preliminary data we can inference the following: 1- FMD is abnormal in HTX recipients, despite their good functional status, probably due to factors unrelated to CHF (e.g. hypertension, renal insufficiency, denervation, and drug effects); 2- LVAD patients also show ED, with possible better adaptation in very long-term survivors; 3- Near-normal FMD values in CHF patients who remain stable with r-LEVO suggest that pulsed treatment may obtain favorable effects at peripheral level, persisting after clearance of the drug and its metabolites.

Acknowledgement/Funding

None

Data on the association between a simplified Mediterranean diet score and the incidence of combined, cardio and cerebro vascular events

Data presented in this article are related to the research article entitled “A priori-defined Mediterranean-like dietary pattern predicts cardiovascular events better in north Europe than in Mediterranean countries” [Veglia et al., 2018]. Data contain information about the incidence of cardiovascular events in a high-risk European population (IMPROVE study) [Baldassarre et al., 2010, 2012, 2013]. Combined vascular events, as well as cardio- and cerebro-vascular events were stratified according to a priori-defined simple Mediterranean Diet (MD) score, based on just seven nutritional items (minimal adherence was 0 and maximal adherence was 7).

Cardiovascular Remodeling after Endovascular Treatment for Thoracic Aortic Injury

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) currently represents the gold standard of treatment for thoracic aortic injury (TAI). Nevertheless, there is an ongoing debate surrounding its safety and subsequent cardiovascular effects. Our aim is to assess heart and vascular structure and function remodeling after TEVAR in TAI young patients.

METHODS

We evaluated 20 patients (18 men, age 41 ± 14 years, 11 treated with Gore CTAG, 9 with Medtronic Valiant) with office and 24-hr blood pressure (BP) with specific vascular stiffness analysis (Mobil-O-Graph), aortic diameters (computed tomography scan) and left ventricular mass index (LVMI echocardiogram). Evaluation was done after a median time of 5.0 ± 3.5 years from the trauma.

RESULTS

After TAI 12 patients (55%) developed hypertension. When patients were divided according to treating time, those treated for more than 3 years show higher LVMI, PWV, and ascending aorta dilatation.

CONCLUSIONS

Our study shows that TEVAR for TAI is associated with heart and vascular remodeling. The presence of TEVAR modifies aortic functional properties and could induce an increase in BP that can promote aortic and cardiac damage, even in young patients.

Treatment with fibrates is associated with higher LAL activity in dyslipidemic patients

Lysosomal acid lipase (LAL) is responsible for the hydrolysis of cholesteryl esters (CE) and triglycerides (TG) within the lysosomes; generated cholesterol and free fatty acids (FFA) are released in the cytosol where they can regulate their own synthesis and metabolism. When LAL is not active, as in case of genetic mutations, CE and TG accumulate in the lysosomal compartment, while the lack of release of cholesterol and FFA in the cytosol leads to an upregulation of their synthesis. Thus, LAL plays a central role in the intracellular homeostasis of lipids. Since there are no indications about the effect of different lipid-lowering agents on LAL activity, aim of the study was to address the relationship between LAL activity and the type of lipid-lowering therapy in a cohort of dyslipidemic patients. LAL activity was measured on dried blood spot from 120 patients with hypercholesterolemia or mixed dyslipidemia and was negatively correlated to LDL-cholesterol levels. Among enrolled patients, ninety-one were taking one or more lipid-lowering drugs, as statins, fibrates, ezetimibe and omega-3 polyunsaturated fatty acids. When patients were stratified according to the type of lipid-lowering treatment, i.e. untreated, taking statins or taking fibrates, LAL activity was significantly higher in those with fibrates, even after adjustment for sex, age, BMI, lipid parameters, liver function, metabolic syndrome, diabetes and statin use. In a subset of patients tested after 3 months of treatment with micronized fenofibrate, LAL activity raised by 21%; the increase was negatively correlated with baseline LAL activity. Thus, the use of fibrates is independently associated with higher LAL activity in dyslipidemic patients, suggesting that the positive effects of PPAR-α activation on cellular and systemic lipid homeostasis can also include an improved LAL activity.

A priori-defined Mediterranean-like dietary pattern predicts cardiovascular events better in north Europe than in Mediterranean countries

BACKGROUND

The Mediterranean Diet (MD) is a model of healthy eating contributing to a favorable health status, but its clinical usefulness is still debated. The aim of this study was to relate the adherence to MD with the incidence of cardio/cerebro-vascular events (VEs) in north and south European participants of the IMPROVE study.

METHODS

IMPROVE is an observational, longitudinal, prospective cohort study involving 3703 individuals from five European countries (Finland, Sweden, Netherlands, France and Italy). The study end-point was the incidence of the first combined cardio/cerebro-vascular event occurring during 36-months follow-up. At baseline, a dietary questionnaire about the usual intake during the year preceding enrollment was administered. Based on 7 nutritional items, a MD Score was constructed in which minimal adherence was 0 and maximal adherence was 7.

RESULTS

Latitude was the strongest determinant of MD score (p < 0.001). VEs occurred in 215 participants. The incidence of VEs was the highest in subjects with MD score 0-1, lower in those with score 2-3 and the lowest in those with score ≥ 4. MD score remained significantly associated with subsequent VEs after adjustment for confounders (hazard ratio for one-point increment of the score = 0.75, p < 0.001) and the association was stronger in northern than in southern countries (p = 0.04 for MD Score × latitude interaction).

CONCLUSIONS

The MD adherence score based on a simple dietary questionnaire detects changes of risk of VEs. According to our findings north Europeans appear to benefit most from VE-prevention when their diet is altered to the MD diet.

Predictive value for cardiovascular events of common carotid intima media thickness and its rate of change in individuals at high cardiovascular risk - Results from the PROG-IMT collaboration

AIMS

Carotid intima media thickness (CIMT) predicts cardiovascular (CVD) events, but the predictive value of CIMT change is debated. We assessed the relation between CIMT change and events in individuals at high cardiovascular risk.

METHODS AND RESULTS

From 31 cohorts with two CIMT scans (total n = 89070) on average 3.6 years apart and clinical follow-up, subcohorts were drawn: (A) individuals with at least 3 cardiovascular risk factors without previous CVD events, (B) individuals with carotid plaques without previous CVD events, and (C) individuals with previous CVD events. Cox regression models were fit to estimate the hazard ratio (HR) of the combined endpoint (myocardial infarction, stroke or vascular death) per standard deviation (SD) of CIMT change, adjusted for CVD risk factors. These HRs were pooled across studies. In groups A, B and C we observed 3483, 2845 and 1165 endpoint events, respectively. Average common CIMT was 0.79mm (SD 0.16mm), and annual common CIMT change was 0.01mm (SD 0.07mm), both in group A. The pooled HR per SD of annual common CIMT change (0.02 to 0.43mm) was 0.99 (95% confidence interval: 0.95-1.02) in group A, 0.98 (0.93-1.04) in group B, and 0.95 (0.89-1.04) in group C. The HR per SD of common CIMT (average of the first and the second CIMT scan, 0.09 to 0.75mm) was 1.15 (1.07-1.23) in group A, 1.13 (1.05-1.22) in group B, and 1.12 (1.05-1.20) in group C.

CONCLUSIONS

We confirm that common CIMT is associated with future CVD events in individuals at high risk. CIMT change does not relate to future event risk in high-risk individuals.

Indicators of Cardiovascular Risk in Metabolic Syndrome: Long Term Follow-up in Italian Patients

BACKGROUND

Cardiovascular risk (CV) factors associated with the metabolic syndrome (MetS) may vary in different populations. In some, hypertension may be the major determinant, in others are low high-density lipoprotein cholesterol (HDL-C), high triglycerides, or another component.

SUBJECTS AND METHODS

Subjects included in this analysis were identified in 2006, among those attending the Lipid Clinic of the Niguarda Hospital, and followed up through to 2013. Patient characteristics (including the occurrence of CV events) were obtained from electronic medical records. MetS was diagnosed according to the American Heart Association/National Heart, Lung and Blood Institute (AHA/NHLBI) guidelines. The carotid intima media thickness (cIMT) was also followed in these patients over the years.

RESULTS

After 7 years a total of 858 subjects had a complete follow-up; 271 of those had MetS. Patients developing a CV event showed elevated baseline cIMT (e.g. cIMTmax ≥ 2.4 mm in males and ≥ 2.2 mm in females); moreover the cIMT in MetS patients was higher at baseline and the rise over 7 years was larger compared with patients without MetS. By examining each body variable for MetS we found that a waist to height ratio (WHtR) ≥ 0.5 was present in nearly all subjects with a CV event.

CONCLUSION

The follow-up data of a series of Italian patients with and without MetS, clearly indicates that the former have a raised cIMT and their arterial IMT progression is greater and the presence of a larger WHtR is apparently linked to a higher incidence of CV events.

Carotid plaque-thickness and common carotid IMT show additive value in cardiovascular risk prediction and reclassification

Background and aims

Carotid plaque size and the mean common carotid intima-media thickness measured in plaque-free areas (PF CC-IMT_mean) have been identified as predictors of vascular events (VEs), but their complementarity in risk prediction and stratification is still unresolved. The aim of this study was to evaluate the independence of carotid plaque thickness and PF CC-IMT_mean in cardiovascular risk prediction and risk stratification.

Methods

The IMPROVE-study is a European cohort (n = 3703), where the thickness of the largest plaque detected in the whole carotid tree was indexed as cIMT_max. PF CC-IMT_mean was also assessed. Hazard Ratios (HR) comparing the top quartiles of cIMT_max and PF CC-IMT_meanversus their respective 1–3 quartiles were calculated using Cox regression.

Results

After a 36.2-month follow-up, there were 215 VEs (125 coronary, 73 cerebral and 17 peripheral). Both cIMT_max and PF CC-IMT_mean were mutually independent predictors of combined-VEs, after adjustment for center, age, sex, risk factors and pharmacological treatment [HR (95% CI) = 1.98 (1.47, 2.67) and 1.68 (1.23, 2.29), respectively]. Both variables were independent predictors of cerebrovascular events (ischemic stroke, transient ischemic attack), while only cIMT_max was an independent predictor of coronary events (myocardial infarction, sudden cardiac death, angina pectoris, angioplasty, coronary bypass grafting). In reclassification analyses, PF CC-IMT_mean significantly adds to a model including both Framingham Risk Factors and cIMT_max (Integrated Discrimination Improvement; IDI = 0.009; p = 0.0001) and vice-versa (IDI = 0.02; p < 0.0001).

Conclusions

cIMT_max and PF CC-IMT_mean are independent predictors of VEs, and as such, they should be used as additive rather than alternative variables in models for cardiovascular risk prediction and reclassification.

•

Taken by themselves, both cIMT_max and PF CC-IMT_mean are associated with the incidence of cardiovascular disease.

•

Complementarity of cIMT_max and PF CC-IMT_mean in cardiovascular risk prediction/reclassification is still under debate.

•

In our study, both cIMT_max and PF CC-IMT_mean were mutually independent predictors of cerebral and coronary vascular events.

•

In reclassification analyses, PF CC-IMT_mean adds to a model including Framingham Risk Factors and cIMT_max and vice-versa.

•

cIMT_max and PF CC-IMT_mean should be used as additive rather than alternative variables in risk prediction/reclassification.

Depletion in LpA-I:A-II particles enhances HDL-mediated endothelial protection in familial LCAT deficiency

The aim of this study was to evaluate the vasoprotective effects of HDL isolated from carriers of LCAT deficiency, which are characterized by a selective depletion of LpA-I:A-II particles and predominance of preβ migrating HDL. HDLs were isolated from LCAT-deficient carriers and tested in vitro for their capacity to promote NO production and to inhibit vascular cell adhesion molecule-1 (VCAM-1) expression in cultured endothelial cells. HDLs from carriers were more effective than control HDLs in promoting eNOS activation with a gene-dose-dependent effect (P_Trend = 0.048). As a consequence, NO production induced by HDL from carriers was significantly higher than that promoted by control HDL (1.63 ± 0.24-fold vs. 1.34 ± 0.07-fold, P = 0.031). HDLs from carriers were also more effective than control HDLs in inhibiting the expression of VCAM-1 (homozygotes, 65.0 ± 8.6%; heterozygotes, 53.1 ± 7.2%; controls, 44.4 ± 4.1%; P_Trend = 0.0003). The increased efficiency of carrier HDL was likely due to the depletion in LpA-I:A-II particles. The in vitro findings might explain why carriers of LCAT deficiency showed flow-mediated vasodilation and plasma-soluble cell adhesion molecule concentrations comparable to controls, despite low HDL-cholesterol levels. These results indicate that selective depletion of apoA-II-containing HDL, as observed in carriers of LCAT deficiency, leads to an increased capacity of HDL to stimulate endothelial NO production, suggesting that changes in HDL apolipoprotein composition may be the target of therapeutic interventions designed to improve HDL functionality.

The use of echocardiography for the non-invasive evaluation of coronary artery disease

In the Western world, there are now millions of patients who undergo clinical procedures that evaluate coronary artery status each year. Methods span from direct imaging using angiography, computerized tomography, to nuclear magnetic imaging as well as to functional studies, such as positron emission tomography. These techniques have provided significant information to physicians, but there is still need for an improved accessibility. Angiographic methods are expensive and expose the patient to significant amounts of radiation, undesirable in younger patients. Among the novel technologies for coronary diagnostics, transthoracic echocardiography (TTE) of coronary arteries has provided an important alternative, particularly in everyday practice. Diagnostic arterial TTE can allow determination of the coronary wall lumen in at least three major coronary segments (left main [LM], left arterial descending [LAD] and right coronary artery [RCA]). Coronary wall thickness using the LAD has been preliminarily shown to be related to the risk of coronary events. Since it is well ascertained that coronary lesions found in any location indicate that at least 80% of the coronary tree is affected, this is very important clinical information. Evaluation of coronary status by TTE is a novel technology providing important information in ischemic syndromes, in cases of coronary malformations and other coronary diseases. KEY MESSAGES Coronary evaluation can be carried out by a variety of both invasive and non-invasive methods, many requiring radiation exposure or patient immobility. Transthoracic echocardiography (TTE) of the coronaries can, in particular, evaluate the coronary wall thickness, and this may be directly related to the coronary disease risk. TTE is a useful method for the monitoring of coronary flow reserve and can allow the detection of coronary malformations.

A New Noninvasive Method for the Accurate and Precise Assessment of Varicose Vein Diameters

The feasibility and reproducibility of a new ultrasonic method for the direct assessment of maximal varicose vein diameter (VVD) were evaluated. A study was also performed to demon strate the capacity of the method to detect changes in venous diameter induced by a phar macologic treatment. Patients with varicose vein disease were recruited. A method that allows the precise positioning of patient and transducer and performance of scans in a gel-bath was developed. Maximal WD was recorded both in the standing and supine positions. The intraassay reproducibility was determined by replicate scans made within 15 minutes in both positions. The interobserver variability was assessed by comparing WDs measured during the first phase baseline examination with those obtained during baseline examinations in the second phase of the study. The error in reproducibility of WD determinations was 5.3% when diameters were evaluated in the standing position and 6.4% when assessed in the supine position. The intramethod agreement was high, with a bias between readings of 0.06 ±0.18 mm and of -0.02 ±0.19 mm, respectively, in standing and supine positions. Correlation coefficients were better than 0.99 in both positions. The method appears to be sensitive enough to detect small changes in VVDs induced by treatments. The proposed technique provides a tool of potential valid use in the detection and in vivo monitoring of WD changes in patients with varicose vein disease. The method offers an innovative approach to obtain a quantitative assessment of varicose vein progression and of treatment effects, thus providing a basis for epidemiologic surveys.

Status and potential clinical value of a transthoracic evaluation of the coronary arteries

The growing need for coronary evaluation has raised interest in non-radioactive, non-invasive monitoring systems. In particular, radiation exposure during coronary investigations has been shown to be a possible cause of an enhanced risk of secondary tumors. Literature search has indicated that transthoracic echocardiography (TTE) has been widely applied to coronary arteries up to 2003, following which the lack of adequate equipment and the increased availability of invasive diagnostics, has reduced interest in this low cost, low-risk technology. The more recent availability of newer, more sensitive machines, allows evaluation of a larger number of arterial trees, including the aorta in newborns, the prenatal aortic intima-media thickness, as well as the detection of coronary artery anomalies in the adult. Improved technology for this highly operator sensitive technique may thus predict a possible evolution toward the clinical diagnostics of coronary disease and, eventually, also of the progression/regression of disease. We sought to evaluate the present status of this seldom quoted non-invasive technology.

Plasma lecithin:cholesterol acyltransferase and carotid intima-media thickness in European individuals at high cardiovascular risk

Lecithin:cholesterol acyltransferase (LCAT) is the enzyme responsible for cholesterol esterification in plasma. LCAT is a major factor in HDL remodeling and metabolism, and it has long been believed to play a critical role in macrophage reverse cholesterol transport (RCT). The effect of LCAT on human atherogenesis is still controversial. In the present study, the plasma LCAT concentration was measured in all subjects (n = 540) not on drug treatment at the time of enrollment in the multicenter, longitudinal, observational IMPROVE study. Mean and maximum intima-media thickness (IMT) of the whole carotid tree was measured by B-mode ultrasonography in all subjects. In the entire cohort, LCAT quartiles were not associated with carotid mean and maximum IMT (P for trend 0.95 and 0.18, respectively), also after adjustment for age, gender, HDL-cholesterol (HDL-C), and triglycerides. No association between carotid IMT and LCAT quartiles was observed in men (P=0.30 and P=0.99 for mean and maximum IMT, respectively), whereas carotid IMT increased with LCAT quartiles in women (P for trend 0.14 and 0.019 for mean and maximum IMT, respectively). The present findings support the concept that LCAT is not required for an efficient reverse cholesterol transport and that a low plasma LCAT concentration and activity is not associated with increased atherosclerosis.

Functional lecithin: cholesterol acyltransferase is not required for efficient atheroprotection in humans

BACKGROUND

Mutations in the LCAT gene cause lecithin:cholesterol acyltransferase (LCAT) deficiency, a very rare metabolic disorder with 2 hypoalphalipoproteinemia syndromes: classic familial LCAT deficiency (Online Mendelian Inheritance in Man No. 245900), characterized by complete lack of enzyme activity, and fish-eye disease (Online Mendelian Inheritance in Man No. 136120), with a partially defective enzyme. Theoretically, hypoalphalipoproteinemia cases with LCAT deficiency should be at increased cardiovascular risk because of high-density lipoprotein deficiency and defective reverse cholesterol transport.

METHODS AND RESULTS

The extent of preclinical atherosclerosis was assessed in 40 carriers of LCAT gene mutations from 13 Italian families and 80 healthy controls by measuring carotid intima-media thickness (IMT). The average and maximum IMT values in the carriers were 0.07 and 0.21 mm smaller than in controls (P=0.0003 and P=0.0027), respectively. Moreover, the inheritance of a mutated LCAT genotype had a remarkable gene-dose-dependent effect in reducing carotid IMT (P=0.0003 for average IMT; P=0.001 for maximum IMT). Finally, no significant difference in carotid IMT was found between carriers of LCAT gene mutations that cause total or partial LCAT deficiency (ie, familial LCAT deficiency or fish-eye disease).

CONCLUSIONS

Genetically determined low LCAT activity in Italian families is not associated with enhanced preclinical atherosclerosis despite low high-density lipoprotein cholesterol levels. This finding challenges the notion that LCAT is required for effective atheroprotection and suggests that elevating LCAT expression or activity is not a promising therapeutic strategy to reduce cardiovascular risk.

Effects of timing and extent of smoking, type of cigarettes, and concomitant risk factors on the association between smoking and subclinical atherosclerosis

BACKGROUND AND PURPOSE

The purpose of this study was to evaluate the effects of timing and extent of smoking, type of cigarettes, and concomitant vascular risk factors (VRFs) on the association between smoking and carotid intima-media thickness (C-IMT) in a lipid clinic population.

METHODS

1804 patients (869 men, age 21 to 85 year) participated in the study. Smoking habits were recorded and C-IMTs were measured by B-mode ultrasound. The associations of C-IMT with smoking status (never, former, and current) and with the cigarettes' content of tar, nicotine, and carbon monoxide (alone or combined to define "light" or "regular" cigarettes) as well as the interactions between smoking status, gender, and VRFs were evaluated before and after adjustment for confounders.

RESULTS

C-IMT was highest in current smokers, lower in former, and lowest in never smokers. C-IMT of former and current smokers differed only after data adjustment for variables describing the extent and timing of smoking exposure. C-IMT was positively related to the number of pack-years (number of cigarettes smoked per day [cigarettes/d] multiplied by number of years smoked/20) in both former and current smokers. There were no differences in C-IMT between smokers of cigarettes with high or low nicotine, tar, or carbon monoxide content. Both diabetes and hypertension interacted positively with smoking in determining C-IMTs.

CONCLUSIONS

In the present cross-sectional observational investigation, carried out in a cohort of patients attending a lipid clinic, consumption of light cigarettes does not reduce the atherogenic effect of smoking on C-IMT. The number of pack-years, cigarettes/d, and years of smoking are relevant covariates in evaluating the effects of smoking on vascular health. The presence of diabetes or hypertension strengthens the association between smoking and cardiovascular risk.

Carotid intima-media thickness and markers of inflammation, endothelial damage and hemostasis

BACKGROUND

Different soluble molecules involved in inflammation, endothelial damage, or hemostasis are recognized as potential cardiovascular risk markers. Studies to assess the role of these markers in the atherosclerotic process by evaluating their relationship to carotid intima-media thickness (C-IMT) tend to provide contrasting results.

PURPOSE

To perform a review of studies addressing the association between C-IMT and soluble markers and to investigate whether the observed inconsistencies could be explained by the characteristics of the patients included in different studies, for example prevalence of atherosclerotic disease (atherosclerotic burden), gender, age, or occurrence of specific vascular risk factors (VRFs).

DATA SOURCES

PubMed and Embase (January 1990 to March 2006).

STUDY SELECTION

Articles in English reporting original cross-sectional studies.

DATA EXTRACTION

Two authors independently extracted data on study design, population, sample size, ultrasonic methodology, and statistical approach.

DATA SYNTHESIS

Despite the marked heterogeneity of results presented in the literature, meta-analysis established that studies showing positive associations between C-IMT and plasma levels of C-reactive protein (CRP) or fibrinogen are in the majority. Funnel plot analyses suggested the absence of an important publication bias. Data on the relationships between C-IMT and other soluble markers are by contrast scanty, contradictory, or unconfirmed by multivariate (as opposed to univariate) analyses, and the freedom from publication bias here cannot be vouched for. The degree of atherosclerotic burden in the population studied does not account for the heterogeneity of findings reported. Gender, noninsulin-dependent diabetes mellitus (NIDDM) and hypercholesterolemia influence the association between C-IMT and CRP. Blood pressure and hypercholesterolemia influence the association between C-IMT and fibrinogen. For all the other soluble markers considered, the number of groups was too small for this kind of statistical considerations.

LIMITATIONS

Heterogeneity in ultrasound methodologies and in statistical approach limited comparability between studies. For most soluble markers, publication bias of positive results cannot be excluded.

CONCLUSIONS

Only CRP and fibrinogen seem to be unequivocally related to C-IMT. For all the other soluble markers considered, no clear-cut conclusions can be drawn.

Measurement of carotid artery intima-media thickness in dyslipidemic patients increases the power of traditional risk factors to predict cardiovascular events

A longitudinal observational study investigated whether the measurement, in clinical practice, of carotid maximum intima-media thickness (Max-IMT) could be combined with the Framingham risk score (FRS) to improve the predictability of cardiovascular events in dyslipidemic patients who are at low or intermediate risk. Max-IMT was measured by ultrasound in 1969 patients attending a lipid clinic. The "best threshold values" (BTVs) above which we considered the Max-IMT to be abnormally high were calculated for our dyslipdemic population for each 10-year age interval in men and women. Two hundred and forty-two patients (age 54+/-10 years; 43.8% women) with an FRS <20%, i.e. at low or intermediate risk, were monitored for more than 5 years. Twenty-four of these patients suffered a cardiovascular event within 5.1+/-2.3 years. Both FRS and Max-IMT proved to be independent outcome predictors (p<0.04, both), with a hazard ratio (HR) of 6.7 (95% CI 1.43, 31.04; p=0.015) in patients in whom FRS was 10-20% and Max-IMT was above the BTV (60th percentile of Max-IMT distribution for men or 80th for women). In Kaplan-Meier analysis, the Max-IMT significantly improved the predictive value of the FRS (chi(2)=8.13, p=0.04). Patients with FRS 10-20% (currently considered intermediate-risk) and also elevated Max-IMT values came into the same high-risk category as patients with FRS 20-30%. The combination of FRS with Max-IMT measurement can be used in routine clinical practice to greatly enhance the predictability of cardiovascular events in the large number of patients who fall into the intermediate-risk category, which currently does not call for aggressive preventive measures.

Correlation of parents' longevity with carotid intima-media thickness in patients attending a Lipid Clinic

The relationship between carotid intima-media thickness (IMT) and the subject's parents' longevity has been investigated. The association between parents' age at death and IMT was estimated in 593 consecutive patients attending a Lipid Clinic by survival-analysis methods. Average maximum IMT (Avg-IMT), maximum IMT (Max-IMT), clinical and laboratory variables and parental age at death, were assessed. Kaplan-Meier analyses showed significant differences in survival curves, low IMTs being associated with long-lived parents (p=0.0003 and 0.001 by log-rank test for fathers and mothers, respectively). A Cox proportional hazards regression model showed that higher carotid IMT values were associated with father's and mother's deaths at an early age, even after adjusting for conventional cardiovascular risk factors. These data were confirmed after the stratification of patients into younger (<65 y) and older (>/=65 y) or into subjects with and without a family history of dyslipidemia or vascular diseases. In addition, by stratifying subjects into those with no, one or two long-lived parents, we observed a significant trend for the combination of father's and mother's longevity on their offspring's IMTs (p<0.01 and 0.05 for Avg-IMT and Max-IMT, respectively). These data highlight a significant relationship between carotid artery IMT and a familial predisposition to be long-lived that is independent of the individual's vascular risk profile.

Recognition of patients with cardiovascular disease by artificial neural networks

BACKGROUND

Artificial neural networks (ANNs) are computer algorithms inspired by the highly interactive processing of the human brain. When exposed to complex data sets, ANNs can learn the mechanisms that correlate different variables and perform complex classification tasks.

AIMS

A database, of 949 patients and 54 variables, was analysed to evaluate the capacity of ANNs to recognise patients with (VE+, n = 196) or without (VE-, n = 753) a history of vascular events on the basis of vascular risk factors (VRFs), carotid ultrasound variables (UVs) or both.

METHOD

The performance of ANN was assessed by calculating the percentage of correct identifications of VE+ and VE- patients (sensitivity and specificity, respectively) and the prediction accuracy (weighted mean between sensitivity and specificity).

RESULTS

The results showed that ANNs can be trained to identify VE+ and VE- subjects more accurately than discriminant analyses. When VRFs and UVs were used as input variables, the prediction accuracies of the ANN providing the best results were 80.8% and 79.2%, respectively. The addition of gender, age, weight, height and body mass index to UVs increased accuracy of prediction to 83.0%. When the ANNs were allowed to choose the relevant input data automatically (I.S. system-Semeion), 37 variables were selected among 54, five of which were UVs. Using this set of variables as input data, the performance of the ANNs in the classification task reached a prediction accuracy of 85.0%. with the 92.0% correct classification of VE+ patients.

CONCLUSIONS

Artificial neural network technology is highly promising in the development of accurate diagnostic tools designed to recognize patients at high risk of cardiovascular diseases.