Peripheral microvascular function is linked to cardiac involvement on cardiovascular magnetic resonance in systemic sclerosis-related pulmonary arterial hypertension

AIMS

Systemic sclerosis (SSc) is characterized by vasculopathy, inflammation, and fibrosis, and carries one of the worst prognoses if patients also develop pulmonary arterial hypertension (PAH). Although PAH is a known prognosticator, patients with SSc-PAH demonstrate disproportionately high mortality, presumably due to cardiac involvement. In this cross-sectional study, the relationship between cardiac involvement revealed by cardiovascular magnetic resonance (CMR) and systemic microvascular disease severity measured with nailfold capillaromicroscopy (NCM) in patients with SSc-PAH is evaluated and compared with patients with idiopathic PAH (IPAH).

METHODS AND RESULTS

Patients with SSc-PAH and IPAH underwent CMR, echocardiography, and NCM with post-occlusive reactivity hyperaemia (PORH) testing on the same day. CMR imaging included T2 (oedema), native, and post-contrast T1 mapping to measure the extracellular volume fraction (ECV, fibrosis) and adenosine-stress-perfusion imaging measuring the relative myocardial upslope (microvascular coronary perfusion). Measures of peripheral microvascular function were related to CMR indices of oedema, fibrosis, and myocardial perfusion. SSc-PAH patients (n = 20) had higher T2 values and a trend towards a higher ECV, compared with IPAH patients (n = 5), and a lower nailfold capillary density (NCD) and reduced capillary recruitment after PORH. NCD correlated with ECV and T2 (r = -0.443 and -0.464, respectively, P < 0.05 for both) and with markers of diastolic dysfunction on echocardiography. PORH testing, but not NCD, correlated with the relative myocardial upslope (r = 0.421, P < 0.05).

CONCLUSION

SSc-PAH patients showed higher markers of cardiac fibrosis and inflammation, compared with IPAH patients. These markers correlated well with peripheral microvascular dysfunction, suggesting that SSc-driven inflammation and vasculopathy concurrently affect peripheral microcirculation and the heart. This may contribute to the disproportionate high mortality in SSc-PAH.

Nailfold capillaroscopy and candidate-biomarker levels in systemic sclerosis-associated pulmonary hypertension: A cross-sectional study

Objectives

Pulmonary hypertension is one of the leading causes of death in systemic sclerosis. Early detection and treatment of pulmonary hypertension in systemic sclerosis is crucial. Nailfold capillaroscopy microscopy, vascular autoantibodies AT1R and ETAR, and several candidate-biomarkers have the potential to serve as noninvasive tools to identify systemic sclerosis patients at risk for developing pulmonary hypertension. Here, we explore the classifying potential of nailfold capillaroscopy microscopy characteristics and serum levels of selected candidate-biomarkers in a sample of systemic sclerosis patients with and without different forms of pulmonary hypertension.

Methods

A total of 81 consecutive systemic sclerosis patients were included, 40 with systemic sclerosis pulmonary hypertension and 41 with no pulmonary hypertension. In each group, quantitative and qualitative nailfold capillaroscopy microscopy characteristics, vascular autoantibodies AT1R and ETAR, and serum levels of 24 soluble serum factors were determined. For evaluation of the nailfold capillaroscopy microscopy characteristics, linear regression analysis accounting for age, sex, and diffusing capacity of the lungs for carbon monoxide percentage predicted was used. Autoantibodies and soluble serum factor levels were compared using two-sample t test with equal variances.

Results

No statistically significant differences were observed in quantitative or qualitative nailfold capillaroscopy microscopy characteristics, or vascular autoantibody ETAR and AT1R titer between systemic sclerosis-pulmonary hypertension and systemic sclerosis-no pulmonary hypertension. In contrast, several serum levels of soluble factors differed between groups: Endostatin, sVCAM, and VEGFD were increased, and CXCL4, sVEGFR2, and PDGF-AB/BB were decreased in systemic sclerosis-pulmonary hypertension. Random forest classification identified Endostatin and CXCL4 as the most predictive classifiers to distinguish systemic sclerosispulmonary hypertension from systemic sclerosis-no pulmonary hypertension.

Conclusion

This study shows the potential for several soluble serum factors to distinguish systemic sclerosis-pulmonary hypertension from systemic sclerosis-no pulmonary hypertension. We found no classifying potential for qualitative or quantitative nailfold capillaroscopy microscopy characteristics, or vascular autoantibodies.

Are Patients With Systemic Sclerosis Subject to an Increased Risk of Developing Superficial Erosion of Atherosclerotic Plaques?

Various inflammatory rheumatic diseases (RDs) are associated with an increased risk of developing cardiovascular (CV) disease. Increased cardiovascular morbidity and mortality has been reported in inflammatory arthritis (including rheumatoid arthritis, psoriatic arthritis, gout, and spondyloarthritis) and connective tissue disease (including vasculitis, systemic lupus erythematosus, and systemic sclerosis [SSc]).

Evaluation of left cardiac chamber function with cardiac magnetic resonance and association with outcome in patients with systemic sclerosis

OBJECTIVE

This study aimed to determine whether lower values of feature-tracking cardiovascular magnetic resonance (CMR)-derived left atrial reservoir strain (LARS) and impaired left ventricular (LV) global longitudinal strain (GLS) were associated with the presence of symptoms and long-term prognosis in patients with SSc.

METHODS

A total of 100 patients {54 [interquartile range (IQR) 46-64] years, 42% male} with SSc who underwent CMR imaging at two tertiary referral centres were included. All patients underwent analysis of LARS and LV GLS using feature-tracking on CMR and were followed-up for the occurrence of all-cause mortality.

RESULTS

The median LV GLS was -21.8% and the median LARS was 36%. On multivariable logistic regression, LARS [odds ratio (OR) 0.964 per %, 95% CI 0.929, 0.998, P = 0.049] was independently associated with New York Heart Association (NYHA) class II-IV heart failure symptoms. Over a median follow-up of 37 (21-62) months, a total of 24 (24%) patients died. Univariable Cox regression analysis demonstrated that LARS [hazard ratio (HR) 0.94 per 1%, 95% CI 0.91, 0.97, P < 0.0001) and LV GLS (HR 1.10 per %, 95% CI 1.03, 1.17, P = 0.005) were associated with all-cause mortality, while LV ejection fraction was not. Likelihood ratio tests demonstrated that LARS provided incremental value over prognostically important clinical and imaging parameters, including late gadolinium enhancement.

CONCLUSION

In patients with SSc, LARS was independently associated with the presence of NYHA class II-IV heart failure symptoms. Although both LARS and LV GLS were associated with all-cause mortality, only LARS provided incremental value over all evaluated variables known to be prognostically important in patients with SSc.

The Prognostic Value of Right Atrial and Right Ventricular Functional Parameters in Systemic Sclerosis

Introduction

Right ventricular (RV) function is of particular importance in systemic sclerosis (SSc), since common SSc complications, such as interstitial lung disease and pulmonary hypertension may affect RV afterload. Cardiovascular magnetic resonance (CMR) is the gold standard for measuring RV function. CMR-derived RV and right atrial (RA) strain is a promising tool to detect subtle changes in RV function, and might have incremental value, however, prognostic data is lacking. Therefore, the aim of this study was to evaluate the prognostic value of RA and RV strain in SSc.

Methods

In this retrospective study, performed at two Dutch hospitals, consecutive SSc patients who underwent CMR were included. RV longitudinal strain (LS) and RA strain were measured. Unadjusted cox proportional hazard regression analysis and likelihood ratio tests were used to evaluate the association and incremental value of strain parameters with all-cause mortality.

Results

A total of 100 patients (median age 54 [46–64] years, 42% male) were included. Twenty-four patients (24%) died during a follow-up of 3.1 [1.8–5.2] years. RA reservoir [Hazard Ratio (HR) = 0.95, 95% CI 0.91–0.99, p = 0.009] and conduit strain (HR = 0.93, 95% CI 0.88–0.98, p = 0.008) were univariable predictors of all-cause mortality, while RV LS and RA booster strain were not. RA conduit strain proved to be of incremental value to sex, atrial fibrillation, NYHA class, RA maximum volume indexed, and late gadolinium enhancement (p < 0.05 for all).

Conclusion

RA reservoir and conduit strain are predictors of all-cause mortality in SSc patients, whereas RV LS is not. In addition, RA conduit strain showed incremental prognostic value to all evaluated clinical and imaging parameters. Therefore, RA conduit strain may be a useful prognostic marker in SSc patients.

Feasibility of online home spirometry in systemic sclerosis-associated interstitial lung disease: a pilot study

OBJECTIVES

Frequent monitoring of forced vital capacity at home may be of added value in patients with SSc-associated interstitial lung disease (SSc-ILD) to monitor disease progression and guide treatment decisions. The aim of this study was to evaluate the feasibility and optimal frequency of online home spirometry using a home monitoring application in patients with SSc-ILD.

METHODS

This was a prospective, observational study in patients with SSc-ILD. Patients evaluated for 3 months the online home monitoring application ILD-online integrated with a Bluetooth-connected spirometer. Patients performed daily home spirometry for 6 weeks and weekly home spirometry for 6 weeks. In addition, patients completed an evaluation questionnaire after 3 months and online patient-reported outcomes at baseline and 3 months.

RESULTS

Ten consecutive patients participated. Mean adherence to home spirometry was 98.8% (s.d. 1.5). Home and hospital spirometry were highly correlated. The mean coefficient of variation was lower for weekly [2.45% (s.d. 1.19)] than daily [3.86% (s.d. 1.45)] forced vital capacity measurements (P = 0.005). All patients considered the home monitoring application and spirometer easy to use and no patients considered home spirometry burdensome. All patients would recommend home monitoring to other patients with SSc.

CONCLUSIONS

Home spirometry using an online home monitoring application is feasible in patients with SSc-ILD, with high adherence and patient satisfaction. Larger long-term studies are needed to assess whether home spirometry can detect the progression of ILD in patients with SSc.

Impact of the B Cell Growth Factor APRIL on the Qualitative and Immunological Characteristics of Atherosclerotic Plaques

Studies on the role of B lymphocytes in atherosclerosis development, have yielded contradictory results. Whereas B lymphocyte-deficiency aggravates atherosclerosis in mice; depletion of mature B lymphocytes reduces atherosclerosis. These observations led to the notion that distinct B lymphocyte subsets have different roles. B1a lymphocytes exert an atheroprotective effect, which has been attributed to secretion of IgM, which can be deposited in atherosclerotic lesions thereby reducing necrotic core formation. Tumor necrosis factor (TNF)-family member 'A Proliferation-Inducing Ligand' (APRIL, also known as TNFSF13) was previously shown to increase serum IgM levels in a murine model. In this study, we investigated the effect of APRIL overexpression on advanced lesion formation and composition, IgM production and B cell phenotype. We crossed APRIL transgenic (APRIL-Tg) mice with ApoE knockout (ApoE-/-) mice. After a 12-week Western Type Diet, ApoE-/-APRIL-Tg mice and ApoE-/- littermates showed similar increases in body weight and lipid levels. Histologic evaluation showed no differences in lesion size, stage or necrotic area. However, smooth muscle cell (α-actin stain) content was increased in ApoE-/-APRIL-Tg mice, implying more stable lesions. In addition, increases in both plaque IgM deposition and plasma IgM levels were found in ApoE-/-APRIL-Tg mice compared with ApoE-/- mice. Flow cytometry revealed a concomitant increase in peritoneal B1a lymphocytes in ApoE-/-APRIL-Tg mice. This study shows that ApoE-/-APRIL-Tg mice have increased oxLDL-specific serum IgM levels, potentially mediated via an increase in B1a lymphocytes. Although no differences in lesion size were found, transgenic ApoE-/-APRIL-Tg mice do show potential plaque stabilizing features in advanced atherosclerotic lesions.

Mycophenolate mofetil but not atorvastatin attenuates atherosclerosis in lupus-prone LDLr(-/-) mice

RATIONALE

Recent clinical and preclinical studies have demonstrated that systemic lupus erythematosus (SLE) is associated with an increased risk for cardiovascular disease (CVD). However, unlike in the general population, little is known regarding the efficacy of atheroprotective interventions in patients with SLE. The current study aims to determine the benefit of lymphocyte inhibition on reducing the atherosclerotic burden in SLE-susceptible LDLr-deficient mice.

METHODS

Female LDLr(-/-) mice were lethally irradiated and reconstituted with bone marrow from C57Bl/6 mice (LDLr.B6) or the SLE-susceptible B6.Sle1.2.3 mice (LDLr.Sle). At 16 weeks post transplant, mice were treated with atorvastatin (10 mg/kg), mycophenolate mofetil (MMF; 40 mg/kg), or both (MMF-A) for 8 weeks, after which the extent of atherosclerosis and the presence of SLE were assessed.

RESULTS

Following 8 weeks of treatment, we observed that atorvastatin-mediated reduction in cholesterol levels attenuated atherogenesis in LDLr.B6 mice but failed to significantly reduce atherosclerotic lesion size in LDLr.Sle mice, in spite of a significant reduction in serum cholesterol levels. Treatment with MMF and MMF-A attenuated atherogenesis in LDLr.B6 and LDLr.Sle mice. In addition, MMF-containing regimens inhibited recruitment of CD4+ T cells to atherosclerotic lesions in LDLr.Sle mice. In these mice, MMF also reduced the proportion of activated splenic T cells, as well as interleukin 10 secretion by T cells. With regard to lupus activity, MMF had no overt effect on anti-double-stranded DNA (dsDNA) antibody titres or kidney function and pathology.

CONCLUSIONS

The current study demonstrates that reduction of cholesterol levels alone is not atheroprotective in lupus-mediated atherogenesis. This is the first study to demonstrate that MMF reduces the atherosclerotic burden in a model of lupus-accelerated atherosclerosis. Our results suggest that MMF treatment may prove beneficial in preventing CVD in patients with SLE.

Statin therapy in lupus-mediated atherogenesis: two birds with one stone?

The atherosclerotic process is accelerated in patients with systemic lupus erythematosus (SLE). In addition to a robust lipid-lowering effect, various immunomodulatory functions have been ascribed to statins. By virtue of the latter they may be able to reduce atherosclerotic vascular disease in SLE by inhibiting immune activation within the arterial wall and by attenuating lupus activity. The effects of statins on SLE as well as on lupus-mediated atherogenesis in vivo are discussed in this viewpoint.

Chemokine ligand 2 genetic variants, serum monocyte chemoattractant protein-1 levels, and the risk of coronary artery disease

OBJECTIVE

In humans, evidence about the association between levels of monocyte chemoattractant protein-1 (MCP-1), its coding gene chemokine (C-C motif) ligand 2 (CCL2), and risk of coronary artery disease (CAD) is contradictory.

METHODS AND RESULTS

We performed a nested case-control study in the prospective EPIC-Norfolk cohort investigating the relationship between CCL2 single-nucleotide polymorphisms (SNPs), MCP-1 concentrations, and the risk of future CAD. Cases (n=1138) were apparently healthy men and women aged 45 to 79 years who developed fatal or nonfatal CAD during a mean follow-up of 6 years. Controls (n=2237) were matched by age, sex, and enrollment time. Using linear regression analysis no association between CCL2 SNPs and MCP-1 serum concentrations became apparent, nor did we find a significant association between MCP-1 serum levels and risk of future CAD. Finally, Cox regression analysis showed no significant association between CCL2 SNPs and the future CAD risk. In addition, we did not find any robust associations between the CCL2 haplotypes and MCP-1 serum concentration or future CAD risk.

CONCLUSIONS

Our data do not support previous publications indicating that MCP-1 is involved in the pathogenesis of CAD.

Cholesteryl Ester Transfer Protein Inhibitor Torcetrapib and Off-Target Toxicity

Background— Torcetrapib, an inhibitor of cholesteryl ester transfer protein, has been shown to increase the cardiovascular event rate despite conferring a significant high-density lipoprotein cholesterol increase. Using data from the Rating Atherosclerotic Disease Change by Imaging with a New CETP Inhibitor (RADIANCE) trials, which assessed the impact of torcetrapib on carotid intima-media thickness (cIMT), we sought to explore potential mechanisms underlying this adverse outcome.

Methods and Results— Data from the RADIANCE 1 and 2 studies, which examined cIMT in 904 subjects with familial hypercholesterolemia and in 752 subjects with mixed dyslipidemia, were pooled. Subjects were randomized to either atorvastatin or torcetrapib combined with atorvastatin. Mean common cIMT progression was increased in subjects receiving torcetrapib plus atorvastatin compared with subjects receiving atorvastatin alone (0.0076±0.0011 versus 0.0025±0.0011 mm/y; P =0.0014). Subjects treated with torcetrapib plus atorvastatin displayed higher postrandomization systolic blood pressure and plasma sodium and bicarbonate levels in conjunction with lower potassium levels. The decrease in potassium levels was associated with the blood pressure increase. Markedly, the use of renin-angiotensin-aldosterone system inhibitors tended to aggravate the blood pressure increase. Subjects receiving torcetrapib plus atorvastatin with the strongest low-density lipoprotein cholesterol reduction showed the smallest cIMT progression, whereas subjects with the highest systolic blood pressure increase showed the largest cIMT progression. High-density lipoprotein cholesterol increase was not associated with cIMT change.

Conclusions— These analyses support mineralocorticoid-mediated off-target toxicity in patients receiving torcetrapib as a contributing factor to an adverse outcome. The absence of an inverse relationship between high-density lipoprotein cholesterol change and cIMT progression suggests that torcetrapib-induced high-density lipoprotein cholesterol increase does not mediate atheroprotection. Future studies with cholesteryl ester transfer protein inhibitors without off-target toxicity are needed to settle this issue.

High-density lipoprotein: a fall from grace?

Based on a plethora of in-vitro and in-vivo research data, high-density lipoprotein cholesterol (HDL) has been regarded as universally atheroprotective. Consequently, pharmacologically mediated HDL increase has emerged as a potential means to improve prevention and treatment of patients with atherosclerotic vascular disease. In particular, inhibition of cholesteryl ester transfer protein (CETP) was considered a promising strategy. Recently, the unanticipated and disappointing results of four large clinical trials with the CETP inhibitor torcetrapib have necessitated refinement of the HDL hypothesis. In addition, the progressive insight that HDL may actually be predominantly a carrier molecule of a wide array of proteins rather than merely a cholesterol-transporter has resulted in the interest to look beyond HDL levels alone. Here we will discuss the impact of recent developments on the HDL hypothesis as well as the advent of even more recent therapeutic developments in the HDL field.

A single bolus infusion of C-reactive protein increases gluconeogenesis and plasma glucose concentration in humans

Recently, we reported that C-reactive protein (CRP) elicits inflammatory and procoagulant responses in humans. In addition, CRP has been associated with the development of type 2 diabetes mellitus. To further explore interactions between CRP and glucose handling, we evaluated the effects of CRP infusion on glucose metabolism in humans. Seven healthy white male volunteers (age, 39.3 +/- 16.9 years) received a single bolus infusion of 1.25 mg/kg purified recombinant human (rh) CRP or CRP-free diluent in a crossover design. C-reactive protein infusion induced an inflammatory response, which was followed by increased plasma concentrations of norepinephrine (3 hours) and cortisol (4 hours). Concomitantly, plasma concentrations of insulin and C-peptide decreased transiently. These metabolic changes increased plasma glucose concentrations from 8 hours after CRP infusion, which was preceded by an increased rate of glucose appearance that was a direct consequence of increased gluconeogenesis. In conclusion, CRP infusion induces an inflammatory response followed by increased norepinephrine and cortisol levels, which results in increased gluconeogenesis. This finding implies that elevated levels of CRP in humans may in fact contribute to altered glucose metabolism and thereby may contribute to the induction of type 2 diabetes mellitus.

Enhanced atherogenesis and altered high density lipoprotein in patients with Crohn's disease

A chronic inflammatory state is a risk factor for accelerated atherogenesis. The aim of our study was to explore whether Crohn's disease (CD), characterized by recurrent inflammatory episodes, is also associated with accelerated atherogenesis. In 60 CD patients and 122 matched controls, carotid intima media thickness (IMT), a validated marker for the burden and progression of atherosclerosis, was assessed ultrasonographically. Additional subgroup analyses, including plasma levels of acute phase reactants and HDL protein profiling, were performed in 11 consecutive patients with CD in remission, 10 patients with active CD, and 15 healthy controls. Carotid IMT in patients with CD was increased compared with healthy volunteers: 0.71 (0.17) versus 0.59 (0.14) mm (P < 0.0001), respectively. In the subgroup analysis, HDL levels in controls and patients in remission were identical [(1.45 (0.48) and 1.40 (0.46) mmol/l; P = 0.797], whereas HDL during exacerbation was profoundly reduced: 1.02 (0.33) (P = 0.022). HDL from patients with active CD and CD patients in remission was characterized by a reduced ability to attenuate oxidation compared with controls (P = 0.008 and P = 0.024 respectively). Patients with CD have increased IMT compared with matched controls, indicative of accelerated atherogenesis. The changes during CD exacerbation in terms of HDL concentration and composition imply a role for impaired HDL protection in these patients.

High-Density Lipoprotein Attenuates Inflammation and Coagulation Response on Endotoxin Challenge in Humans

OBJECTIVE

Low high-density lipoprotein (HDL) cholesterol is a strong independent cardiovascular risk factor, which has been attributed to its role in reverse cholesterol transport. Whereas HDL also has potent antiinflammatory effects, the relevance of this property remains to be established in humans. In the present study, we evaluated whether there is a relation between HDL and sensitivity toward a low-dose endotoxin challenge.

METHODS AND RESULTS

Thirteen healthy men with genetically determined isolated low HDL cholesterol (averaging 0.7+/-0.1 mmol/L) and 14 age- and body weight-matched healthy men with normal/high HDL cholesterol levels (1.9+/-0.4 mmol/L) were challenged with low-dose endotoxin intravenously (1 ng/kg body weight). The incidence and severity of endotoxin-associated clinical symptoms was increased in the low HDL group. Accordingly, both the inflammatory response (tumor necrosis factor-alpha, IL-1beta, IL-6, IL-8, and monocyte chemoattractant protein-1) as well as thrombin generation (prothrombin activation fragments F(1+2)) were significantly increased in the low HDL group on endotoxin challenge.

CONCLUSIONS

Low HDL in healthy males is associated with increased sensitivity toward inflammatory stimuli as reflected by enhanced inflammatory and coagulation responses on endotoxin challenge. These antiinflammatory effects of HDL in humans may lend further support to HDL-increasing interventions, particularly in proinflammatory conditions, such as acute coronary syndromes.

Effect of torcetrapib on carotid atherosclerosis in familial hypercholesterolemia

BACKGROUND

Torcetrapib, an inhibitor of cholesteryl ester transfer protein, may reduce atherosclerotic vascular disease by increasing levels of high-density lipoprotein (HDL) cholesterol.

METHODS

A total of 850 patients with heterozygous familial hypercholesterolemia underwent B-mode ultrasonography at baseline and at follow-up to measure changes in carotid intima-media thickness. The patients completed an atorvastatin run-in period and were subsequently randomly assigned to receive either atorvastatin monotherapy or atorvastatin combined with 60 mg of torcetrapib for 2 years.

RESULTS

After 24 months, in the atorvastatin-only group, the mean (+/-SD) HDL cholesterol level was 52.4+/-13.5 mg per deciliter and the mean low-density lipoprotein (LDL) cholesterol level was 143.2+/-42.2 mg per deciliter, as compared with 81.5+/-22.6 mg per deciliter and 115.1+/-48.5 mg per deciliter, respectively, in the torcetrapib-atorvastatin group. During the study, average systolic blood pressure increased by 2.8 mm Hg in the torcetrapib-atorvastatin group, as compared with the atorvastatin-only group. The increase in maximum carotid intima-media thickness, the primary measure of efficacy, was 0.0053+/-0.0028 mm per year in the atorvastatin-only group and 0.0047+/-0.0028 mm per year in the torcetrapib-atorvastatin group (P=0.87). The secondary efficacy measure, annualized change in mean carotid intima-media thickness for the common carotid artery, indicated a decrease of 0.0014 mm per year in the atorvastatin-only group, as compared with an increase of 0.0038 mm per year in the torcetrapib-atorvastatin group (P=0.005).

CONCLUSIONS

In patients with familial hypercholesterolemia, the use of torcetrapib with atorvastatin, as compared with atorvastatin alone, did not result in further reduction of progression of atherosclerosis, as assessed by a combined measure of carotid arterial-wall thickness, and was associated with progression of disease in the common carotid segment. These effects occurred despite a large increase in HDL cholesterol levels and a substantial decrease in levels of LDL cholesterol and triglycerides. (ClinicalTrials.gov number, NCT00136981 [ClinicalTrials.gov].).

Pleiotropic Effects of Statins: Stabilization of the Vulnerable Atherosclerotic Plaque?

Acute coronary syndromes (ACS), i.e. unstable angina and myocardial infarction, are the leading causes of death in developed countries and developing countries alike. Lipid lowering intervention studies have demonstrated a 30% risk reduction in recurrent cardiovascular events and death, despite only modest improvement in angiographic stenosis. This discrepancy suggested that cholesterol lowering by statins may lead to stabilization of vulnerable plaques rather than reducing stenosis per sé. The predominant effect of statins is to lower lipid levels by inhibiting cholesterol biosynthesis. Besides the lipid lowering effects, statins have also been shown to modulate the inflammatory status and improve endothelial function amongst others, commonly referred to as "pleiotropic effects". In the present review we will discuss different determinants which lead to plaque vulnerability and subsequently we will expand on the plaque stabilizing or "pleiotropic" effects of statin treatment.

Designs of RADIANCE 1 and 2: carotid ultrasound studies comparing the effects of torcetrapib/atorvastatin with atorvastatin alone on atherosclerosis

OBJECTIVE

The RADIANCE studies were designed to assess the effects of torcetrapib/atorvastatin (T/A) compared with atorvastatin alone on slowing atherosclerotic progression in patients with heterozygous familial hypercholesterolemia (RADIANCE 1) or mixed hyperlipidemia (RADIANCE 2), as measured by change in carotid intima-media thickness (CIMT).

RESEARCH DESIGN AND METHODS

RADIANCE 1 and 2 were randomized, double-blind, controlled trials with a duration of 2 years. In both studies, eligible subjects began treatment with atorvastatin during a run-in period and were titrated to target LDL-C levels defined by NCEP ATP III guidelines. Subjects then proceeded to a double-blind randomized treatment period where they received one of two regimens: (i) fixed combination T/A (torcetrapib dose, 60 mg), or (ii) atorvastatin alone. In both regimens, the dose of atorvastatin was established during the run-in period (20-80 mg, RADIANCE 1; 10-80 mg RADIANCE 2). B-mode ultrasonography was performed in duplicate at baseline and at end of study, and every 6 months in between.

MAIN OUTCOME MEASURES

The primary efficacy measure in both studies was the annualized rate of change in maximum CIMT of 12 pre-defined carotid segments. Further outcome measures included lipid and safety assessments.

CURRENT STATUS

The number of subjects randomized was 904 in RADIANCE 1 and 752 in RADIANCE 2. Results are anticipated in 2007.

The dyslipidemia of chronic renal disease: effects of statin therapy

PURPOSE OF REVIEW

Dyslipidemia is a prevalent condition in patients with chronic renal disease, but is often left untreated. Statin treatment constitutes an effective way to improve lipid abnormalities. This review summarizes present studies on dyslipidemia and its treatment in patients with chronic renal disease.

RECENT FINDINGS

The specific dyslipidemia in renal disease is associated with the presence of proteinuria and decreased creatinine clearance, and may even adversely affect the progression of chronic renal disease. Statin therapy may have renoprotective effects due to a combination of lipid lowering and pleiotropic effects. Statins exert several anti-inflammatory properties and lead to a decrease of proteinuria. Post-hoc analyses of large-scale lipid lowering trials have shown that the reduction of cardiovascular risk was equivalent to the reduction achieved in patients without chronic renal failure. We feel, however, that if intervention with statins is postponed until patients reach end-stage renal disease, statins have limited benefit.

SUMMARY

Present studies suggest that patients with renal disease should be screened early for dyslipidemia and that statins have to be considered as the lipid lowering therapy of choice. These drugs reduce cardiovascular risk. Further studies are needed to firmly establish whether statins preserve renal function.

Serum levels of mannose-binding lectin and the risk of future coronary artery disease in apparently healthy men and women

OBJECTIVE

To determine the association between serum levels of mannose-binding lectin (MBL) and the risk of future coronary artery disease (CAD) in apparently healthy men and women.

METHODS AND RESULTS

We performed a prospective case-control study among apparently healthy men and women nested in the EPIC-Norfolk cohort. Baseline concentrations of MBL were measured in serum samples of 946 patients who experienced a myocardial infarction or died of CAD during follow-up, and 1799 matched controls who remained free of CAD. Among men, median MBL levels were 1.63 ng/mL (interquartile range [IQR]: 0.59 to 3.80) in cases and 1.20 ng/mL (IQR: 0.48 to 3.37) in controls. Among women, median MBL levels were 1.02 ng/mL (IQR: 0.43 to 2.95) in cases and 1.01 ng/mL (IQR: 0.43 to 2.94) in controls. After adjustment, the odds ratio in men for future CAD was 1.59 (95% confidence interval [CI]: 1.09 to 2.32; P for linearity=0.01) for those in the highest quartile compared with those in the lowest quartile. In women no such relation was observed.

CONCLUSIONS

Elevated levels of MBL are associated with an increased risk of future CAD in apparently healthy men but not in women. The sex difference merits further exploration.

Mycophenolate mofetil (MMF): firing at the atherosclerotic plaque from different angles?

Atherosclerosis is characterized by a persistent, low-grade inflammatory state in which immune cell activation is inseparably linked to plaque formation and destabilization. The T-lymphocyte in particular has emerged as a pivotal player throughout the course of atherogenesis. As a consequence, the concept that immune modulation is a suitable target for cardiovascular prevention is currently an important focus of research. Mycophenolate mofetil (MMF) has emerged as a non-competitive inhibitor of inosine monophosphate dehydrogenase (IMPDH) that exerts cytostatic effects, particularly on proliferating T-lymphocytes. In addition, MMF has other immune-modulating effects, such as downregulation of the expression of adhesion molecules and attenuation of monocyte and macrophage responses. Given the added benefit that MMF is well tolerated, this immunosuppressive agent constitutes an attractive candidate for the modulation of inflammatory activation in atherogenesis. The present review provides an overview of the potential anti-atherogenic properties of MMF.

Cardiovascular disease in systemic lupus erythematosus: has the time for action come?

PURPOSE OF REVIEW

The recognition that inflammation is a hallmark of atherosclerotic disease has led to a series of studies reporting accelerated atherogenesis in chronic inflammatory diseases. Indeed, systemic lupus erythematosus is associated with an increased incidence of cardiovascular disease and the etiology thereof deserves closer attention.

RECENT FINDINGS

The association between systemic lupus erythematosus and accelerated atherosclerosis has recently been confirmed by surrogate-marker studies for cardiovascular disease in patients with systemic lupus erythematosus. Since the propensity towards cardiovascular disease cannot solely be explained by classical risk factors, disease-specific pathways have been put forward as additional risk factors.

SUMMARY

In the present review, we will discuss several of these factors as well as their potential impact for future prevention strategies in systemic lupus erythematosus.

Atorvastatin

The introduction of statins has drastically changed the treatment and prevention of atherosclerotic vascular disease. By lowering lipid levels and reducing the risk of coronary heart disease, these drugs are among the most effective at reducing morbidity and mortality available to clinical practice. In fact, these compounds have demonstrated the reversible nature of the process of atherosclerosis and can be considered the most useful drugs we currently have in our armamentarium in the prevention of atherosclerosis and its clinical sequelae. Atorvastatin provides pronounced lipid lowering in a broad range of individuals with hypercholesterolaemia and, as such, is an appropriate first-line therapy for patients at low to high risk of coronary heart disease. Reductions in total and low-density lipoprotein cholesterol achieved with atorvastatin have been shown to translate into reductions in risk of cardiovascular morbidity and mortality in both primary and secondary prevention settings. Significant clinical benefits have specifically been observed among patients with Type 2 diabetes and in those with acute coronary syndromes. In common with other members of the statin class, atorvastatin is well tolerated, and adverse events are generally mild and transient in nature. Despite the significant clinical benefits provided by atorvastatin, its full potential in the management of atherosclerotic disease has yet to be wholly explored; however, studies currently ongoing will answer many of the outstanding questions.