Meta-analysis of the studies assessing temporal changes in coronary plaque volume using intravascular ultrasound

Progression of coronary artery calcification at the crossroads: sign of progression or stabilization of coronary atherosclerosis?

Coronary artery calcification (CAC) has been strongly established as an independent predictor of adverse events, with a significant incremental prognostic value over traditional risk stratification algorithms. CAC progression has been associated with a higher rate of events. In parallel, several randomized studies and meta-analysis have shown the effectiveness of statins to slow progression and even promote plaque regression. However, evidence regarding the effect of routine medical therapy on CAC has yielded conflicting results, with initial studies showing significant CAC regression, and contemporaneous data showing rather the opposite. Accordingly, there is currently a great controversy on whether progression of CAC is a sign of progression or stabilization of coronary artery disease (CAD). The finding of inexorable CAC progression despite the implementation of intensive contemporaneous medical therapy suggests that further understanding of this phenomenon should be undertaken before the implementation of CAC as a surrogate endpoint for longitudinal studies, or for prospective follow-up of patients under routine medical treatment.

Relationship between changes in coronary atherosclerotic plaque burden measured by intravascular ultrasound and cardiovascular disease outcomes: a systematic literature review

Objective Evidence from coronary imaging studies suggests an association between increased atherosclerotic plaque burden and cardiovascular disease (CVD) outcomes. A systematic review was performed to evaluate the relationship between coronary atherosclerotic plaque burden changes measured by intravascular ultrasound (IVUS) and CVD outcomes. Research design and methods Rigorous systematic review methodology was used to identify prospective studies of any design assessing the relationship between atherosclerotic plaque volume (percentage or total atheroma volume [PAV or TAV]) changes and CVD outcomes, using multivariable analyses. Main outcome measures CVD outcomes including major adverse cardiac events (MACEs) and major adverse cardiac and cerebrovascular events (MACCEs). Results Literature searches from inception to February 2015 retrieved 6958 records after de-duplication. From these four studies (14 papers) were included. One study reported a significantly lower rate of CVD outcomes associated with a greater reduction in PAV (hazard ratio [HR] 0.26, 95% confidence interval [CI] 0.07-0.83). One study reported that large plaque volume was significantly associated with a greater risk of major adverse cardiac events (MACEs) (HR 1.73, 95% CI: 1.02-2.96). Similarly, a third study reported a significant increase in MACE with an increase in baseline PAV (HR 1.51, 95% CI: 1.06-2.51). Only one potentially inadequately powered Japanese study did not find a statistically significant relationship between PAV changes and MACE. Conclusions The current evidence suggests an independent and statistically significant association between increases in coronary atherosclerotic plaque burden measured by IVUS and greater long-term risk of future CVD outcomes. However, this evidence comes from a limited number of studies which mainly focus on Japanese populations and populations after PCI. Further large prospective studies are required to confirm these findings.

Impact of statin therapy on coronary plaque composition: a systematic review and meta-analysis of virtual histology intravascular ultrasound studies

BACKGROUND

Virtual histology intravascular ultrasound (VH-IVUS) imaging is an innovative tool for the morphological evaluation of coronary atherosclerosis. Evidence for the effects of statin therapy on VH-IVUS parameters have been inconclusive. Consequently, we performed a systematic review and meta-analysis to investigate the impact of statin therapy on plaque volume and its composition using VH-IVUS.

METHODS

The search included PubMed, Cochrane Library, Scopus and Embase (through 30 November 2014) to identify prospective studies investigating the effects of statin therapy on plaque volume and its composition using VH-IVUS.

RESULTS

We identified nine studies with 16 statin treatment arms and 830 participants. There was a significant effect of statin therapy in reducing plaque volume (standardized mean difference (SMD): -0.137, 95 % confidence interval (CI): -0.255, -0.019; P = 0.023), external elastic membrane volume (SMD: -0.097, 95 % CI: -0.183, -0.011; P = 0.027) but not lumen volume (SMD: -0.025, 95 % CI: -0.110, +0.061; P = 0.574). There was a significant reduction in fibrous plaque volume (SMD: -0.129, 95 % CI: -0.255, -0.003; P = 0.045) and an increase of dense calcium volume (SMD: +0.229, 95 % CI: +0.008, +0.450; P = 0.043), while changes in fibro-fatty (SMD: -0.247, 95 % CI: -0.592, +0.098; P = 0.16) and necrotic core (SMD: +0.011, 95 % CI: -0.144, +0.165; P = 0.892) tissue volumes were not statistically significant.

CONCLUSIONS

This meta-analysis indicates a significant effect of statin therapy on plaque and external elastic membrane volumes and fibrous and dense calcium volumes. There was no effect on lumen volume, fibro-fatty and necrotic tissue volumes.

The Effect of Statin Therapy on Coronary Plaque Composition Using Virtual Histology Intravascular Ultrasound: A Meta-Analysis

OBJECTIVE

Previous studies have indicated that statin therapy may promote plaque regression. However, the impact of statin therapy on plaque composition has not been clearly elucidated. We performed a meta-analysis to investigate the effect of statin therapy on coronary plaque composition as assessed by virtual histology intravascular ultrasound (VH-IVUS).

METHODS

Online databases were searched from inception to March 1, 2015. Studies providing VH-IVUS volumetric analyses of coronary plaque composition at baseline and follow-up in patients receiving statin therapy were included. Weighted mean difference (WMD) using a random-effects model was used.

RESULTS

Ten studies involving 682 patients were included. There was a substantial reduction in fibrous volume between baseline and follow-up (WMD: -2.37 mm3, 95% confidence interval (CI) -4.01 to -0.74 mm3, P=0.004), and a significant increase in dense calcium (DC) volume (WMD: 0.89 mm3, 95% CI 0.70 to 1.08 mm3, P<0.00001). No significant change was seen in fibro-fatty and necrotic core (NC) volumes. In stratified analyses, the fibrous volume was decreased significantly (WMD: -3.39 mm3, 95% CI -6.56 to -0.21 mm3, P=0.04) and the absolute DC volume (WMD: 0.99 mm3, 95% CI 0.23 to 1.76 mm3, P=0.01) was increased in the subgroup with ≥12 months follow-up, whereas no significant change was observed in the subgroup with < 12 months follow-up. Similarly, a substantial decrease in fibrous volume (WMD: -2.01 mm3, 95% CI -3.05 to -0.96 mm3, P< 0.0002) and an increase in DC volume (WMD: 0.90 mm3, 95% CI 0.70 to 1.10 mm3, P< 0.00001) were observed in the subgroup with high-intensive statin therapy, while the change in fibrous and DC volumes approached statistical significance (P=0.05 and P=0.05, respectively) in the subgroup with low-intensive statin therapy.

CONCLUSIONS

Statin treatment, particularly of high-intensity and long-term duration, induced a marked modification in coronary plaque composition including a decrease in fibrous tissue and an increase in DC.

Effect of statin therapy on the progression of coronary atherosclerosis

BACKGROUND

An increasing number of authors employing intravascular ultrasound (IVUS) and virtual histology (VH-IVUS) have investigated the effect of statin use on plaque volume (PV) and plaque composition. However, inconsistent results have been reported. Therefore, we conducted a meta-analysis to determine the appropriate regimen of statins to effectively stabilize vulnerable coronary plaques.

METHODS

Online electronic databases were carefully searched for all relevant studies. We compared mean values of PV and plaque composition between baseline and follow-up in patients receiving statin therapy. We pooled treatment effects and calculated mean differences (MD) with the 95% confidence interval (CI) using a random-effects model. By stratified analyses, we explored the influence of clinical presentation, dose and duration of statin treatment, and low-density lipoprotein-cholesterol (LDL-C) levels on the effects of statins.

RESULTS

Seventeen studies involving 2,171 patients were analyzed. Statin therapy significantly decreased PV (-5.3 mm(3); 95% CI: -3.3 mm(3) to -7.2 mm(3) P < 0.001), without heterogeneity. When considering the dose and duration of statins used, only subgroups employing a high dose and long duration demonstrated a significant reduction in PV (p < 0.001). A significant decrease in PV was noted if achieved LDL-C levels were <100 mg/dL (p < 0.001). Statin treatment could induce a twofold decrease in PV in patients with acute coronary syndrome (ACS) compared with that observed in patients with stable angina pectoris (SAP). A regressive trend was seen for necrotic core volume (MD: -2.1 mm(3); 95% CI: -4.7 mm(3) to 0.5 mm(3), P = 0.11). However, statin use did not induce a significant change for fibrotic, fibro-fatty, or dense calcium compositions.

CONCLUSIONS

Our meta-analysis demonstrated that statin therapy (especially that involving a high dose and long duration and achieving <100 mg/dL LDL-C levels) can significantly decrease PV in patients with SAP or ACS. These data suggested that statins can be used to reduce the atheroma burden for secondary prevention by appropriately selecting the statin regimen. No significant change in plaque composition was seen after statin therapy.

Secondary revascularization after CABG surgery

CABG surgery is an effective way to improve symptoms and prognosis in patients with advanced coronary atherosclerotic disease. Despite multiple improvements in surgical technique and patient treatment, graft failure after CABG surgery occurs in a time-dependent fashion, particularly in the second decade after the intervention, in a substantial number of patients because of atherosclerotic progression and saphenous-vein graft (SVG) disease. Until 2010, repeat revascularization by either percutaneous coronary intervention (PCI) or surgical techniques was performed in these high-risk patients in the absence of specific recommendations in clinical practice guidelines, and within a culture of inadequate communication between cardiac surgeons and interventional cardiologists. Indeed, some of the specific technologies developed to reduce procedural risk, such as embolic protection devices for SVG interventions, are largely underused. Additionally, the implementation of secondary prevention, which reduces the need for reintervention in these patients, is still suboptimal. In this Review, graft failure after CABG surgery is examined as a clinical problem from the perspective of holistic patient management. Issues such as the substrate and epidemiology of graft failure, the choice of revascularization modality, the specific problems inherent in repeat CABG surgery and PCI, and the importance of secondary prevention are discussed.

Four-year clinical outcomes of the OLIVUS-Ex (impact of Olmesartan on progression of coronary atherosclerosis: evaluation by intravascular ultrasound) extension trial

BACKGROUND

The previous OLIVUS trial reported a positive role in achieving a lower rate of coronary atheroma progression through the administration of olmesartan, an angiotension-II receptor blocking agent (ARB), for stable angina pectoris (SAP) patients requiring percutaneous coronary intervention (PCI). However, the benefits between ARB administration on long-term clinical outcomes and serial atheroma changes by IVUS remain unclear. Thus, we examined the 4-year clinical outcomes from OLIVUS according to treatment strategy with olmesartan.

METHODS

Serial volumetric IVUS examinations (baseline and 14 months) were performed in 247 patients with hypertension and SAP. When these patients underwent PCI for culprit lesions, IVUS was performed in their non-culprit vessels. Patients were randomly assigned to receive 20-40mg of olmesartan or control, and treated with a combination of β-blockers, calcium channel blockers, glycemic control agents and/or statins per physician's guidance. Four-year clinical outcomes and annual progression rate of atherosclerosis, assessed by serial IVUS, were compared with major adverse cardio- and cerebrovascular events (MACCE).

RESULTS

Cumulative event-free survival was significantly higher in the olmesartan group than in the control group (p=0.04; log-rank test). By adjusting for validated prognosticators, olmesartan administration was identified as a good predictor of MACCE (p=0.041). On the other hand, patients with adverse events (n=31) had larger annual atheroma progression than the rest of the population (23.8% vs. 2.1%, p<0.001).

CONCLUSIONS

Olmesartan therapy appears to confer improved long-term clinical outcomes. Atheroma volume changes, assessed by IVUS, seem to be a reliable surrogate for future major adverse cardio- and cerebrovascular events in this study cohort.

Intravascular ultrasound imaging for assessing regression and progression in coronary artery disease

New imaging techniques have been used as surrogate markers of atherosclerotic burden to determine the effects of pharmacologic intervention. The aim of this study was to better determine potential utility and limitations of intravascular ultrasound (IVUS) imaging for assessing regression and progression in coronary artery disease. Medline was searched for randomized trials using IVUS for assessing regression and progression in coronary artery disease (through September 2009). A comparison of IVUS studies with large trials evaluating the same issue with clinical end points was performed. A total of 26 relevant reports (8,631 patients randomized [median 207.5], 5,794 patients analyzed [median 152], duration 2 weeks to 3.4 years [median 12 months]) were identified. Three frequently used IVUS variables were the focus of the analysis: (1) nominal change in plaque volume, (2) percentage change in plaque volume, and (3) nominal change in percentage plaque volume. These variables were presented in 21, 12, and 11 studies, respectively. The variables were the primary end points in 4, 5, and 4 studies, respectively. Large variance with a relatively small difference was noticed in all 3 variables. Fewer than half of the variables showed statistically significant differences in comparing groups. Comparison of IVUS studies with large trials evaluating the same issue with clinical end points showed consistent and inconsistent results. In conclusion, the current method of calculating plaque volume using IVUS seems logical, and some clinical outcomes trials have yielded some evidence. Future studies are needed to determine which IVUS variable is the best surrogate to determine the effects of pharmacologic intervention in patients with coronary artery disease.

Plaque regression determined by intravascular ultrasound predicts long-term outcomes of patients with acute coronary syndrome

AIM

The usefulness of drugs to treat plaque regression is assessed by intravascular ultrasound (IVUS); however, the impact of plaque regression on clinical outcomes in patients with acute coronary syndrome (ACS) has not been established; therefore, we investigated the relationship between coronary plaque regression and long-term clinical outcomes.

METHODS

We analyzed data from 86 patients who underwent percutaneous coronary intervention (PCI) and who were assessed in detail at baseline and at 6 months of follow-up by measuring proximal non-culprit sites of PCI lesions using volumetric IVUS. Patients were divided according to changes in plaque volume over 6 months into one group with plaque regression (n =55; 64.0%) and another with progression (n =31; 36.0%). They were followed up observationally for a mean of 1,736 days.

RESULTS

Baseline characteristics at the time of ACS were similar between the groups. The probability of event-free survival was significantly higher in the regression group than in the progression group as estimated by the Kaplan-Meier method (Log-rank test, p =0.032). Furthermore, the Cox hazards model revealed the relative contribution of plaque regression as a predictor of cardiovascular events (hazard ratio: 0.26; 95% CI, 0.07 to 0.83; p =0.023).

CONCLUSIONS

Plaque regression determined by volumetric IVUS over a period of 6 months was associated with a lower rate of cardiovascular events among patients with ACS. This study also demonstrated that plaque regression could be a surrogate marker of future cardiovascular events.

Are changes in carotid intima-media thickness related to risk of nonfatal myocardial infarction? A critical review and meta-regression analysis

BACKGROUND

Carotid intima-media thickness (CIMT) is increasingly being used as a surrogate end point in randomized control trials (RCTs) of novel cardiovascular therapies. However, it remains unclear whether changes in CIMT that result from these therapies correlate with nonfatal myocardial infarction (MI).

METHODS

We performed a literature search of RCTs from 1990-2009 that used CIMT. Eligible RCTs (1) included quantitative and sequential assessments in CIMT at least 1 year apart and (2) reported nonfatal MI. Across RCTs, random-effects metaregression was employed to correlate differences in mean change in CIMT between treatment and control groups over time with the log odds ratios of developing nonfatal MI during follow-up.

RESULTS

Overall, we identified 28 RCTs with 15,598 patients. Differences in mean change in CIMT over time between treatment and control groups correlated with developing nonfatal MI during follow-up: for each 0.01 mm per year smaller rate of change in CIMT, the odds ratio for MI was 0.82 (95% CI, 0.69 to 0.96; P = .018). Results were similar in subgroups of RCTs with >1 year follow-up (P = .018) and those with at least 50 subjects in the treatment group (P = .019). However, there was no significant relationship between mean change in CIMT and nonfatal MI in RCTs evaluating statin therapy or those with high CIMTs at baseline (P > .20 in both instances).

CONCLUSIONS

Less progression in CIMT over time is associated with a lower likelihood of nonfatal MI in selected RCTs; however, these findings were inconsistent at times, suggesting caution in using CIMT as a surrogate end point.

Impact of olmesartan on progression of coronary atherosclerosis a serial volumetric intravascular ultrasound analysis from the OLIVUS (impact of OLmesarten on progression of coronary atherosclerosis: evaluation by intravascular ultrasound) trial

OBJECTIVES

The aim of this study was to evaluate the impact of olmesartan on progression of coronary atherosclerosis.

BACKGROUND

Prior intravascular ultrasound (IVUS) trial results suggest slowing of coronary atheroma progression with some medicines but have not shown convincing evidence of regression with angiotension-II receptor blocking agents.

METHODS

A prospective, randomized, multicenter trial-OLIVUS (Impact of OLmesartan on progression of coronary atherosclerosis: evaluation by IntraVascular UltraSound)-was performed in 247 stable angina pectoris patients with native coronary artery disease. When these patients underwent percutaneous coronary intervention for culprit lesions, IVUS was performed in their nonculprit vessels (without angiographically documented coronary stenosis [<50%]). Patients were randomly assigned to receive 10 to 40 mg of olmesartan or control and treated with a combination of beta-blockers, calcium channel blockers, diuretics, nitrates, glycemic control agents, and/or statins per physician's guidance. Serial IVUS examinations (baseline and 14-month follow-up) were performed to assess coronary atheroma volume. Volumetric IVUS analyses included lumen, plaque, vessel volume, percent atheroma volume (PAV), percent change in total atheroma volume (TAV) and PAV.

RESULTS

Patient characteristics and blood pressure control were identical between the 2 groups. However, follow-up IVUS showed significantly decreased TAV and percent change in PAV in the olmesartan group (5.4% vs. 0.6 % for TAV and 3.1% vs. -0.7% for percent change in PAV, control vs. olmesartan, p < 0.05 for all).

CONCLUSIONS

These observations suggest a positive role in a potentially lower rate of coronary atheroma progression through the administration of olmesartan, an angiotension-II receptor blocking agent, for patients with stable angina pectoris.

Rosuvastatin along the cardiovascular continuum: from JUPITER to AURORA

Dyslipidemia is one of the major causes of atherosclerosis, although in the last few years an increase in cholesterol control rates has been reported. However, results from the European Action on Secondary and Primary Prevention by Intervention to Reduce Events (EUROASPIRE) surveys indicate that approximately 50% of the patients with ischemic heart disease still do not attain LDL-cholesterol goals despite the use of lipid-lowering therapy (including statins). Rosuvastatin is a new and potent statin that produces greater reductions of LDL-cholesterol when compared with other agents in this class. Furthermore, rosuvastatin provides additional benefits in the lipid profile such as increased HDL-cholesterol, and decreased triglycerides, total cholesterol, apolipoprotein B and apolipoprotein B:A-1 ratio. Cardiovascular disease is a continuum: from risk factors to subclinical organ damage and finally to overt clinical cardiovascular disease. Several trials have investigated the effects of rosuvastatin along this cardiovascular continuum. The results provided by the GALAXY program emphasize the importance of the early treatment with rosuvastatin in the cardiovascular continuum to achieve the greatest benefit. In this paper, the efficacy and safety of rosuvastatin along the cardiovascular continuum is reviewed.

Intensive lipid lowering may reduce progression of carotid atherosclerosis within 12 months of treatment: the METEOR study

BACKGROUND

In several statin trials, vascular event rates for treatment groups begin to separate 1 year after commencement of treatment. For atherosclerosis progression, the temporal sequence of the effect has not been defined. We used data from the Measuring Effects on intima media Thickness: an Evaluation Of Rosuvastatin (METEOR) trial to determine the earliest time point at which significant differences in atherosclerosis progression rates could be detected after initiation of statin therapy.

METHODS

The METEOR trial was a double-blind, randomized placebo-controlled trial that studied the effect of LDL-C lowering with 40 mg rosuvastatin on the rate of change of carotid intima media thickness (CIMT) measured by B-mode ultrasound amongst 984 low risk subjects. Ultrasound assessments were made at baseline and every 6 months up to 2 years.

RESULTS

Rosuvastatin treatment was associated with a 49% reduction in LDL-C-C, a 34% reduction in total cholesterol, an 8.0% increase in HDL-C and a 16% reduction in triglycerides (all P < 0.0001 compared with placebo). The difference in rate of mean maximum CIMT progression between the rosuvastatin and placebo groups (based on near and far wall measurements from both left and right common carotid and internal carotid segments and carotid bifurcation) was not statistically significant after 6 months (0.0023 mm year(-1) and 0.0106 mm year(-1), respectively P = 0.34). After 12 months, CIMT progression rates were significantly different between the groups: 0.0032 mm year(-1) and 0.0133 mm year(-1) in the rosuvastatin-treated and placebo-treated groups, respectively (P = 0.049). This divergence grew with further follow-up: -0.0009 mm year(-1) and 0.0131 mm year(-1) after 18 months (P < 0.001) and -0.0014 mm year(-1) and 0.0131 mm year(-1) after 24 months of treatment (P < 0.001). Results were stronger for the mean common CIMT progression (based on near and far wall measurements from both left and right common carotid segments).

CONCLUSION

Aggressive LDL-C lowering seems to exert its beneficial effect on atherosclerosis progression during the first 12 months of treatment. This parallels the timing of event reduction seen in clinical trials and suggests that the efficacy of lipid lowering treatment on CIMT progression can be evaluated in trials with a duration of 1 year, given sufficient sample size, high precision of measurements and a treatment effect comparable to that seen in METEOR.

Prevention of atherosclerosis in patients living with HIV

INVESTIGATIONAL PRODUCT: Rosuvastatin (Crestor; Astra Zeneca).

ACTIVE INGREDIENTS

Rosuvastatin (5 mg).

STUDY TITLE

Prevention of Atherosclerosis in Patients Living with HIV.

PHASE OF STUDY

Phase III.

AIMS

PRIMARY AIM: To assess whether rosuvastatin therapy could slow the progression of the carotid intima-media thickness (C-IMT; as measured by the change in the mean IMT of the near and far walls of the distal common carotid arteries) over 2 years in HIV-infected patients (HIV-IP).

SECONDARY AIMS

To assess whether rosuvastatin therapy could reduce highly sensitive C reactive protein (hs-CRP) inflammatory marker that is increased in HIV-IP.To assess the effect of rosuvastatin therapy on serum lipid levels (total cholesterol [TC], low-density lipoprotein [LDL] cholesterol, high-density lipoprotein [HDL] cholesterol and triglycerides [TG]) and apolipoproteins (APO A1, APO B and APO B/A1).To assess the safety of rosuvastatin in HIV-IP through the evaluation of clinical laboratory analyses (liver function tests and creatine kinase) and adverse events (AEs).

STUDY DESIGN

Two-year randomized, double-blind, placebo-controlled, parallel group study.

PLANNED SAMPLE SIZE

320 HIV-IP.

SUMMARY OF ELIGIBILITY CRITERIA

HIV-IP who are aged between 30 and 60 years, with a CD4 count. greater than 200 cells/mm(3). Patients must be stable on combination antiretroviral therapy (cART) for at least 12 months and have a 10-year CVD risk of less than 20% (using the Framingham risk score).

NUMBER OF STUDY CENTERS

One.

DURATION OF TREATMENT

Two years (5 mg rosuvastatin or placebo once daily).

DOSE AND ROUTE OF ADMINISTRATION

Oral rosuvastatin (5 mg) once daily. The incidence of cardiovascular disease (CVD) in HIV-IP is at least three times higher than in the general population and further increases each year with combination anti-retroviral therapy (cART). The carotid atherosclerosis progression rate is 10 times higher in HIV-IP than in uninfected individuals. The aim of this study is to assess whether therapy with 5 mg rosuvastatin could: 1) Slow the progression in the mean IMT of the distal common carotid arteries over two years in HIV-IP.2) Change the concentration in the inflammatory marker--hs-CRP, which is increased in HIV-IP.3) Change the concentrations of TC, LDL cholesterol, HDL cholesterol, TG, apolipoproteins (APO) B, APO A1 and APO B/A1.4) Be administered safely in the study population. Pharmacological intervention with rosuvastatin will be evaluated in a double-blind, placebo-controlled, randomized clinical trial in HIV-IP treated with cART not matching the published selection criteria for lipid-lowering therapy. For the first time, this study will investigate anti-inflammatory and anti-atherogenic effects of a pharmacological lipid-lowering agent in HIV-IP that may lead to the reduction of CVD.

Non-invasive assessment of vulnerable plaque

BACKGROUND

Sudden cardiac death or unheralded acute coronary syndromes are common initial manifestations of coronary atherosclerosis and most such events occur at sites of non-flow limiting coronary atherosclerosis.

OBJECTIVE

Non-invasive detection of high-risk plaques might provide a means to improve risk stratification in primary and secondary prevention settings.

METHODS

This review is focused on the potential of multidetector computed tomography coronary angiography (MDCT-CA) to provide the opportunity to identify different aspects of plaque vulnerability throughout the coronary tree in an accurate, fast, safe and non-invasive manner.

CONCLUSION

Coronary artery calcium scoring, on top of established risk stratification, could potentially be a cost-effective strategy for primary prevention. MDCT-CA allows a non-invasive evaluation of several features commonly seen in vulnerable plaques and has demonstrated an independent prognostic value on a patient basis. The value of the technique itself might result, potentially, in a better estimation of the relative risk of an invidual plaque to rupture.

Why to screen heart disease in diabetes

The expanding diabetic epidemic and the high risk of cardiovascular events in diabetic patients suggest that screening heart disease in this population is an important issue. Nonetheless, the advisability of large-scale screening in asymptomatic individuals with diabetes is debated, because available techniques are expensive and have suboptimal diagnostic accuracy. Moreover, all diabetic patients should be treated aggressively as if they all had a positive screening test, because diabetes could be considered a coronary risk equivalent. In this article, we underline the importance of an early diagnosis of coronary artery disease and heart failure in diabetic patients, suggesting that positive screening tests have significant implications in clinical management.

Peroxisome Proliferator-Activated Receptor-γ–Mediated Effects in the Vasculature

Peroxisome proliferator-activated receptor (PPAR)-γ is a nuclear receptor and transcription factor in the steroid superfamily. PPAR-γ agonists, the thiazolidinediones, are clinically used to treat type 2 diabetes. In addition to its function in adipogenesis and increasing insulin sensitivity, PPAR-γ also plays critical roles in the vasculature. In vascular endothelial cells, PPAR-γ activation inhibits endothelial inflammation by suppressing inflammatory gene expression and therefore improves endothelial dysfunction. In vascular smooth muscle cells, PPAR-γ activation inhibits proliferation and migration and promotes apoptosis. In macrophages, PPAR-γ activation suppresses inflammation by regulating gene expression and increases cholesterol uptake and efflux. A recurring theme in many cell types is the modulation of the innate immunity system particularly through altering the activity of the nuclear factor κB. This system is likely to be even more prominent in modulating disease in vascular cells. The effects of PPAR-γ in the vascular cells translate into the beneficial function of this transcription factor in vascular disorders, including hypertension and atherosclerosis. Both human genetic studies and animal studies using transgenic mice have demonstrated the importance of PPAR-γ in these disorders. However, recent clinical studies have raised significant concerns about the cardiovascular side effects of thiazolidinediones, particularly rosiglitazone. Weighing the potential benefit and harm of PPAR-γ activation and exploring the functional mechanisms may provide a balanced view on the clinical use of these compounds and new approaches to the future therapeutics of vascular disorders associated with diabetes.

Effect of perindopril on coronary remodelling: insights from a multicentre, randomized study

AIMS

This study sought to evaluate the effect of perindopril in coronary remodelling.

METHODS AND RESULTS

In this sub-study of a double-blind, multicentre trial, patients without clinical evidence of heart failure were randomized to perindopril 8 mg/day or placebo for at least 3 years and IVUS investigation was performed at both time-points. Positive and negative remodelling were defined as a relative increase (positive remodelling) or decrease (negative remodelling) of the mean vessel cross-sectional area (CSA)>2 SD of the mean intra-observer difference. A total of 118 matched evaluable IVUS (711 matched 5 mm segments) were available at follow-up. After a median follow-up of 3.0 (inter-quartile range 1.9, 4.1) years, there was no significant difference in the change of plaque CSA between perindopril (360 segments) and placebo (351 segments) groups, P=0.27. Conversely, the change in vessel CSA was significantly different between groups (perindopril -0.18+/-2.4 mm2 vs. placebo 0.19+/-2.4, P = 0.04). Negative remodelling occurred more frequently in the perindopril than in the placebo group (34 vs. 25%, P=0.01). In addition, the placebo group showed a larger, although not significant, mean remodelling index (RI) than the perindopril group (1.03+/-0.2 vs. 1.00+/-0.2, P=0.06). The temporal change in vessel dimensions assessed by the RI was significantly correlated with the change in plaque dimensions (r=0.48, P<0.0001).

CONCLUSION

In this sub-analysis of a multicentre, controlled study, long-term administration of perindopril was associated with a constrictive remodelling pattern without affecting the lumen.