Relationship between cardiovascular risk factors and atherosclerotic disease burden measured by intravascular ultrasound

The relative and combined ability of stress hyperglycemia ratio and N-terminal pro-B-type natriuretic peptide to predict all-cause mortality in diabetic patients with multivessel coronary artery disease

BACKGROUND

Stress hyperglycemia ratio (SHR) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) are independently associated with increased mortality risk in diabetic patients with coronary artery disease (CAD). However, the role of these biomarkers in patients with diabetes and multivessel disease (MVD) remains unknown. The present study aimed to assess the relative and combined abilities of these biomarkers to predict all-cause mortality in patients with diabetes and MVD.

METHODS

This study included 1148 diabetic patients with MVD who underwent coronary angiography at Tianjin Chest Hospital between January 2016 and December 2016. The patients were divided into four groups according to their SHR (SHR-L and SHR-H) and NT-proBNP (NT-proBNP-L and NT-proBNP-H) levels. The primary outcome was all-cause mortality. Multivariate Cox regression analyses were performed to evaluate the association of SHR and NT-proBNP levels with all-cause mortality.

RESULTS

During a mean 4.2 year follow-up, 138 patients died. Multivariate analysis showed that SHR and NT-proBNP were strong independent predictors of all-cause mortality in diabetic patients with MVD (SHR: HR hazard ratio [2.171; 95%CI 1.566-3.008; P < 0.001; NT-proBNP: HR: 1.005; 95%CI 1.001-1.009; P = 0.009). Compared to patients in the first (SHR-L and NT-proBNP-L) group, patients in the fourth (SHR-H and NT-proBNP-H) group had the highest mortality risk (HR: 12.244; 95%CI 5.828-25.721; P < 0.001). The areas under the curve were 0.615(SHR) and 0.699(NT-proBNP) for all-cause mortality. Adding either marker to the original models significantly improved the C-statistic and integrated discrimination improvement values (all P < 0.05). Moreover, combining SHR and NT-proBNP levels into the original model provided maximal prognostic information.

CONCLUSIONS

SHR and NT-proBNP independently and jointly predicted all-cause mortality in diabetic patients with MVD, suggesting that strategies to improve risk stratification in these patients should incorporate SHR and NT-porBNP into risk algorithms.

HbA1c, Coronary atheroma progression and cardiovascular outcomes

Background and aims

We tested the hypothesis that on-treatment HbA1c levels independently associate with coronary atheroma progression and major adverse cardiovascular events (MACE: death, myocardial infarction, cerebrovascular accident, coronary revascularization, or hospitalization for unstable angina) rates.

Methods

We performed a post-hoc pooled analysis of data from seven prospective, randomized trials involving serial coronary intravascular ultrasonography (IVUS). The percent atheroma volume (PAV) was calculated as the proportion of the entire vessel wall occupied by atherosclerotic plaque. Using multivariable mixed modeling, we determined the association of on-treatment HbA1c with annualized change in PAV. Cox proportional hazard models were used to assess the association of HbA1c with incidence of MACE.

Results

Among 3,312 patients (mean age 58.6±9years, 28.4%women) average on-treatment HbA1c was 6.2±1.1%. Overall, there was no net significant annualized change in PAV (0.12±0.19%, p = 0.52). In a fully adjusted multivariable analysis (following adjustment of age, sex, body mass index, systolic blood pressure, smoking, low- and high-density lipoprotein cholesterol, triglyceride levels, peripheral vascular disease, trial, region, and baseline PAV), higher on-treatment HbA1c levels were independently associated with annualized changes in PAV [beta-estimate (95% confidence interval): 0.13(0.08, 0.19), p < 0.001]. On-treatment HbA1c levels were independently associated with MACE [hazard ratio (95% confidence interval): 1.13(1.04, 1.23), p = 0.005].

Conclusions

Independent of achieved cardiovascular risk factor control, greater HbA1c levels significantly associate with coronary atheroma progression rates and clinical outcomes. These results support the notion of a direct, specific effect of glycemic control upon coronary atheroma and atherosclerotic events, supporting the rationale of therapies designed to directly modulate it.

Prognostic Significance of Preprocedural N-Terminal Pro-B-Type Natriuretic Peptide Assessment in Diabetic Patients With Multivessel Coronary Disease Undergoing Revascularization

Background and Aims: The N-terminal pro-B-type natriuretic peptide (NT-proBNP) may predict adverse cardiovascular outcomes in patients with diabetes. However, its prognostic value in patients with multivessel disease (MVD) undergoing coronary revascularization remains unclear. This study aimed to evaluate the prognostic significance of preprocedural NT-proBNP levels in diabetic patients with MVD undergoing coronary revascularization.

Methods: A total of 886 consecutive diabetic patients with MVD who underwent coronary revascularization were enrolled in this study. Patients were divided into quartiles according to their pre-procedural NT-proBNP levels. Kaplan-Meier curves and Cox regression analyses were performed to evaluate the risk of cardiovascular events, including all-cause death, cardiovascular death, myocardial infarction (MI), stroke, and major adverse cardiovascular events (MACE), according to the NT-proBNP quartiles.

Results: During a median follow-up period of 4.2 years, 111 patients died (with 82 being caused by cardiovascular disease), 133 had MI, 55 suffered from stroke, and 250 experienced MACE. Kaplan-Meier curves demonstrated that NT-proBNP levels were significantly associated with higher incidences of all-cause death, cardiovascular death, MI, and MACE (log-rank test, P < 0.001, respectively). Multivariate Cox regression analysis revealed that NT-proBNP level was an independent predictor of adverse outcomes, including all-cause death (HR, 1.968; 95% CI, 1.377–2.812; P < 0.001), cardiovascular death (HR, 1.940; 95% CI, 1.278–2.945; P = 0.002), MI (HR, 1.722; 95% CI, 1.247–2.380; P = 0.001), and MACE (HR, 1.356; 95% CI, 1.066–1.725; P = 0.013). The role of NT-proBNP in predicting adverse outcomes was similar in patients with stable angina pectoris and acute coronary syndrome. Moreover, preprocedural NT-proBNP alone discriminated against the SYNTAX II score for predicting all-cause death [area under the curve (AUC), 0.662 vs. 0.626, P = 0.269], cardiovascular death (AUC, 0.680 vs. 0.622, P = 0.130), MI (AUC, 0.641 vs. 0.579, P = 0.050), and MACE (AUC, 0.593 vs. 0.559, P = 0.171). The addition of NT-proBNP to the SYNTAX II score showed a significant net reclassification improvement, integrated discrimination improvement, and improved C-statistic (all P < 0.05).

Conclusion: NT-proBNP levels were an independent prognostic marker for adverse outcomes in diabetic patients with MVD undergoing coronary revascularization, suggesting that preprocedural NT-proBNP measurement might help in the risk stratification of high-risk patients.

Greater plaque burden and cholesterol content may explain an increased incidence of non-culprit events in diabetic patients: a Lipid-Rich Plaque substudy

AIMS 

Diabetes mellitus (DM) is associated with increased cardiovascular morbidity and mortality. The multicentre, prospective Lipid-Rich Plaque trial (LRP) examined non-culprit (NC) non-obstructive coronary segments with a combined near-infrared spectroscopy (NIRS)-intravascular ultrasound (IVUS) catheter. This study assessed the differences in NC plaque characteristics and their influence on major adverse cardiac events (MACE) in diabetic and non-diabetic patients.

METHODS AND RESULTS 

Patients with known DM status were divided into no diabetes, diabetes not treated with insulin (non-ITDM), and insulin-treated diabetes (ITDM). The association between presence and type of DM and NC-MACE was assessed at both the patient and coronary segment levels by Cox proportional regression modelling. Out of 1552 patients enrolled, 1266 who had their diabetes status recorded were followed through 24 months. Female sex, hypertension, chronic kidney disease, peripheral vascular disease, and high body mass index were significantly more frequent in diabetic patients. The ITDM group had more diseased vessels, at least one NC segment with a maxLCBI4 mm ≥400 in 46.2% of patients, and maxLCBI4 mm ≥400 in nearly one out of six Ware segments (15.2%, 125/824 segments). The average maxLCBI4 mm significantly increased from non-diabetic patients (NoDM) to non-insulin-treated diabetic patients (non-ITDM) to insulin-treated diabetic patients (ITDM; 137.7 ± 161.9, 154.8 ± 173.6, 182.9 ± 193.2, P < 0.001, respectively). In patients assigned to follow-up (692 ± 129 days), ITDM doubled the incidence of NC-MACE compared with the absence of diabetes (15.7% vs. 6.9%, P = 0.0008). The presence of maxLCBI4 mm>400 further increased the NC-MACE rate to 21.6% (Kaplan-Meier estimate).

CONCLUSION 

Cholesterol-rich NC plaques detected by NIRS-IVUS were significantly more frequent in diabetic patients, especially those who were insulin-treated, and were associated with an increased NC-MACE during follow-up.

Time trends in ischaemic heart disease incidence and mortality over three decades (1990-2019) in 20 Western European countries: systematic analysis of the Global Burden of Disease Study 2019

AIMS

To investigate and compare changes in the rates of ischaemic heart disease (IHD) incidence and mortality between 1990 and 2019 in 20 high-income Western European countries with similar public health systems and low cardiovascular risk.

METHODS AND RESULTS

The 2020 updated version of the Global Burden of Disease database was searched. Variability and differences in IHD incidence and mortality rates (per 100 000) between countries over time, were calculated. A piecewise linear (join point) regression model was used to identify the slopes of these trends and the points in time at which significant changes in the trends occur. Ischaemic heart disease incidence and mortality rates varied widely between countries but decreased for all between 1990 and 2019. The relative change was greater for mortality than for incidence. Ischaemic heart disease incidence rates declined by approximately 36% between 1990 and 2019, while mortality declined by approximately 60%. Breakpoint analysis showed that the largest decreases in incidence and mortality occurred between 1990 and 2009 (-32%, -52%, respectively), with a much slower decrease after that (-5.9%, -17.6%, respectively), and even a slight increase for some countries in recent years. The decline in both incidence and mortality was lower in the Mediterranean European countries compared to the Nordic and Central European regions.

CONCLUSIONS

In the Western European countries studied, the decline in age-standardized IHD incidence over three decades was slower than the decline in age-standardized IHD mortality. Decreasing trends of both IHD incidence and mortality has substantially slowed, and for some countries flattened, in more recent years.

Effects of Statin Plus Ezetimibe on Coronary Plaques in Acute Coronary Syndrome Patients with Diabetes Mellitus: Sub-Analysis of PRECISE-IVUS Trial

AIM

Coronary plaque regression is weak in acute coronary syndrome (ACS) patients with diabetes mellitus (DM). We evaluated whether dual lipid-lowering therapy (DLLT) with ezetimibe and atorvastatin attenuates coronary plaques in ACS patients with DM.

METHODS

The prospective, randomized controlled, multicenter PRECISE-IVUS (Plaque Regression with Cholesterol Absorption Inhibitor or Synthesis Inhibitor Evaluated by Intravascular Ultrasound) trial assigned 246 patients undergoing percutaneous coronary intervention to DLLT or atorvastatin monotherapy and evaluated IVUS-derived changes in percent atheroma volume (ΔPAV), at baseline and 9-12-month follow-up, in 126 ACS cases, including 25 DM patients. The atorvastatin dose was up-titrated to achieve low-density lipoprotein cholesterol (LDL-C) ＜70 mg/dL.

RESULTS

In DM patients, the monotherapy group (n=13) and the DLLT group (n=12) showed a similar prevalence of coronary risks and baseline lipid profiles. During the study, the change in LDL-C level was similar between DM and non-DM patients. Compared with non-DM patients, DM patients showed weaker regression of ΔPAV by DLLT than those who underwent monotherapy (DM: -2.77±3.47% vs. -0.77±2.51%, P=0.11; non-DM: -2.01±3.36% vs. -0.08±2.66%, P=0.008). The change in LDL-C level was not correlated with ΔPAV in non-DM patients, but there was significant correlation between the change in LDL-C level and ΔPAV in DM patients (r=0.52, P=0.008).

CONCLUSIONS

ACS patients with DM showed weaker coronary plaque regression than their counterparts. A significant correlation between the change in LDL-C level and ΔPAV in DM patients suggested that more intensive lipid-lowering therapy is required in ACS patients with DM.

The history of proprotein convertase subtilisin kexin-9 inhibitors and their role in the treatment of cardiovascular disease

A consensus has formed based on epidemiological studies and clinical trials that intervention to reduce low density lipoprotein cholesterol (LDL-C) will reduce cardiovascular disease (CVD) events. This has progressively reduced the thresholds for intervention and targets for treatment. Whist statins are sufficient for many people in primary prevention, they only partially achieve the newer targets of secondary prevention for established CVD. Increasing use of statins has highlighted that 1–2% cannot tolerate these drugs. Other cholesterol-lowering drugs such as ezetimibe add to the benefits of statins but have limited efficacy. The discovery of activating mutations in proprotein convertase subtilisin kexin-9 (PCSK9) as a cause of familial hypercholesterolaemia while inactivating mutations lower LDL-C led to the idea to develop PCSK9 inhibitors as drugs. This article reviews the history of lipid-lowering therapies, the discovery of PCSK9 and the development of PCSK9 inhibitors. It reviews the key trials of the current antibody-based drugs and how these have influenced new guidelines. It also reviews the controversy caused by their cost and the increasing application of health economics to determine the optimum strategy for implementation of novel therapeutic pathways and surveys other options for targeting PCSK9 as well as other LDL-C lowering compounds in late development.

Coronary Atherosclerotic Plaque Volume Quantified by Computed Tomographic Angiography in Smokers Compared to Nonsmokers

RATIONALE AND OBJECTIVES

We sought to compare the prevalence and volume of lipid plaque, fibrous plaque, and calcified plaque in patients with smokers versus nonsmokers.

MATERIALS AND METHODS

We studied consecutive patients suspected of coronary artery disease and who underwent coronary computed tomography angiography. A structured interview and review of existing clinical data was conducted before computed tomography angiography to collect information on demographic characteristics, the presence of cardiovascular risk factors. The volume of lipid, fibrous, and calcified plaque were automatically calculated and marked in different colors according to predefined Hounsfield unit thresholds. The prevalence and volume of plaques were compared between smokers and nonsmokers.

RESULTS

Overall 6380 patients (3351 men and 3029 women, mean age 55.35 years) were finally analyzed, of whom 2075 (32.5%) were smokers, and 4305 (67.5%) were never smokers. The prevalence of any plaque in smokers was significantly higher compared to never smokers (47.7% vs. 32.3%, p < 0.001). Smoking was an independent risk factor of the presence of any plaque after correcting for age, gender, body mass index, hypertension, dyslipidemia, diabetes, and family history in a multivariate model (odds ratio = 1.250 (1.088-1.437), p = 0.002). The volume of lipid plaque, fibrous plaque, calcified plaque, and total plaque in smokers was significantly greater than nonsmokers (p < 0.001).

CONCLUSION

The prevalence and volume of lipid plaque, fibrous plaque, and calcified plaque were significantly higher in smokers versus never smokers.

Differences in coronary plaque morphology between East Asian and Western White patients: an optical coherence tomography study

AIMS

Prevalence of coronary artery disease as well as cardiac mortality varies between Asian and White patients. However, the link between race and plaque characteristics in patients with coronary artery disease remains largely unexplored. Thus, we aimed to investigate the detailed culprit plaque characteristics between East Asian and White patients using optical coherence tomography.

PATIENTS AND METHODS

A total of 101 East Asians were matched to 101 White patients. Matching parameters included age, sex, clinical presentation, hyperlipidemia, diabetes mellitus, and lesion location.

RESULTS

There were no differences in underlying pathology (rupture vs. erosion) of acute coronary syndrome (P=0.935). Lesion length was longer (18.0±6.0 vs. 14.6±5.4 mm; P<0.002), lipid length was greater (9.4±4.6 vs. 7.2±3.8 mm; P<0.023), lipid index was higher (1635±987 vs. 1104±730; P=0.002), and mean reference area was larger (8.1±3.0 vs. 6.5±2.4 mm; P<0.021) in White patients compared with East Asian patients.

CONCLUSION

There are significant differences in plaque morphology between East Asian and White patients even after controlling for confounders. Our findings underscore key differences in atherosclerosis between East Asian and White populations, and may have to be taken into consideration when interpreting the results of future research.

Predictors of thromboxane levels in patients with non-ST-elevation acute coronary syndromes on chronic aspirin therapy

High levels of thromboxane A2 (TxA2), a key mediator of platelet activation and aggregation, are associated with an increased risk of cardiovascular events. We aimed at assessing the predictors of higher plasma levels of TxB2, the stable metabolite of TxA2, in consecutive patients presenting with non-ST-elevation acute coronary syndrome (NSTE-ACS) on previous aspirin (ASA) treatment undergoing coronary angiography. Ninety-eight consecutive patients (age 61 ± 11, 75% males) with NSTE-ACS, on previous chronic ASA treatment, were prospectively enrolled in this study. Coronary disease extent was assessed by angiography according to the Bogaty score. In all patients, admission plasma levels of TxB2 (pg/ml) were measured by enzyme-linked immunosorbent assay, and patients showing TxB2 levels in the fourth quartile were compared to patients showing TxB2 levels in the lower quartiles. Multivariable logistic regression analysis showed that platelet count (odds ratio [OR] 1.18, 95% confidence interval [CI] 1.02–1.63, p=0.04), multivessel coronary disease (OR 1.37, 95% CI 1.13–3.67, p=0.03), and coronary atherosclerosis extent index (OR 1.91, 95% CI 1.45–6.79, p=0.001) were independent predictors of TxB2 level upper quartile. Of note, C-reactive protein serum levels were similar in patients with TxB2 levels in the upper quartile as compared to those in the lower quartiles (p=0.49). In conclusion, NSTE-ACS patients with severe coronary atherosclerosis may have incomplete suppression of TxA2 production despite chronic ASA therapy. This finding suggests that additional efforts should be made to lower TxA2 levels in patients with widespread coronary artery disease.

Patients With Diabetes Without Significant Angiographic Coronary Artery Disease Have the Same Risk of Myocardial Infarction as Patients Without Diabetes in a Real-World Population Receiving Appropriate Prophylactic Treatment

OBJECTIVE

The risk of myocardial infarction (MI) in patients with diabetes is greater than for patients without diabetes. Consequently, prophylactic treatment is recommended for patients with diabetes and risk factors for ischemic heart disease. We aimed to estimate the risk of adverse cardiac events in patients with and without diabetes with and without coronary artery disease (CAD) after coronary angiography (CAG).

RESEARCH DESIGN AND METHODS

A population-based cohort of patients registered in the Western Denmark Heart Registry who underwent CAG between 1 January 2003 and 31 December 2012 was stratified according to the presence or absence of obstructive CAD and diabetes. End points were death, cardiac death, and MI. Unadjusted and adjusted rate ratios (RRs) were calculated by using patients without diabetes and without CAD as the reference group.

RESULTS

We included 93,866 patients of whom 12,544 (13.4%) had diabetes at the time of CAG. Median follow-up was 4.1 years. Patients with and without diabetes without obstructive CAD had the same adjusted risk of death (RR 1.03 [95% CI 0.92-1.15]), cardiac death (RR 1.21 [95% CI 0.90-1.64]), and MI (RR 0.88 [95% CI 0.65-1.17]). Patients with diabetes without CAD were more often treated with statins (75.3% vs. 46.0%) and aspirin (65.7% vs. 52.7%) than patients without diabetes and CAD.

CONCLUSIONS

In a real-world population, patients with diabetes with high rates of statin and aspirin treatment had the same risk of cardiovascular events as patients without diabetes in the absence of angiographically significant CAD.

Risk factors of atherosclerotic tissue types in single-vessel and intermediate coronary lesions: a cross-sectional study

BACKGROUND

Few data exist that correlate lesion-related risk factors such as conventional cardiovascular risks or lipoprotein-associated phospholipase A2 (Lp-PLA2) with tissue types within atherosclerotic plaques in patients with single-vessel and intermediate coronary lesions.

METHODS

One hundred and ninety-two patients with single-vessel and intermediate coronary lesions were enrolled in a cross-sectional study and divided into two groups: stable angina pectoris (SAP) and acute coronary syndrome (ACS) groups. Data regarding clinical characteristics and Lp-PLA2 mass were collected. Using iMAP-IVUS, lumen areas were manually traced to determine the minimum lumen area (MLA) at 1-mm intervals in diseased segments. At the minimum lumen lesion, areas of different types of atherosclerotic tissue [i.e., areas of fibrous plaque tissue (FP), fibro-fatty tissue (FF), dense calcium (DC) and necrotic core (NC)], vascular external elastic membrane (EEMCSA) and plaque and media (P&MCSA) were calculated using the built-in iMap algorithm. Plaque burden was computed as P&MCSA divided by EEMCSA.

RESULTS

In a univariate analysis, glycosylated hemoglobin A1C (GHbA1C), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), hypertension, Lp-PLA2 and a history of taking statins predicted the degree of FP and NC area, as well as plaque burden, but were not significant predictors of FF or DC area. In a multivariate analysis, Lp-PLA2 and HbA1c remained independent predictors of plaque burden, FP and NC area. However, the results of the regression analyses were not identical when the SAP and ACS groups were analyzed separately. Lp-PLA2, diabetes and NC area were significant predictors of acute coronary lesions, and the predictive value of Lp-PLA2 was confirmed by the finding of a high area-under-the-curve in a ROC analysis (0.837, 95% CI:0.778-0.895, P = 0.000), as well as by the reasonable sensitivity and specificity of cut-off values.

CONCLUSIONS

GHbA1C and Lp-PLA2 were strong independent predictors of plaque burden and FP and NC area at the minimum lumen lesion in patients with single-vessel and intermediate coronary lesions. Furthermore, Lp-PLA2 has a certain predictive value for acute coronary lesions.

Biolimus-Eluting StenT For de-novo coRonary artery dIsease in patiENts with Diabetes mellituS: the BESTFRIENDS multicentre registry

AIMS

Coronary inflammation and healing influence outcomes of diabetic patients treated with Percutaneous coronary revascularization (PCI). Stents covered with biodegradable polymers (bp) may offer advantages over nonerodible polymer ones, because polymer reabsorption extinguish coronary inflammation and favours healing. Aim of our study was to assess the safety and efficacy of bp-biolimus-eluting stent (bp-BES) in a large series of consecutive diabetic patients.

METHODS

From 2009 to 2013 we retrospectively enrolled consecutive diabetic patients treated with PCI and bp-BES implantation. Primary end points were target lesion revascularization (TLR) and stent thrombosis rates.

RESULTS

Study cohort counted 747 patients. Multivessel disease was present in 48.2% with a mean stent/patient ratio of 1.860.78. During the hospital stay no stent thrombosis occurred. At 3-year follow-up we observed a 1.5% cumulative incidence of cardiac death, 1.1% of myocardial infarction and 6.3% of TLR. Stent thrombosis occurred in 1.1% of patients, all in the first 2 years of follow-up. Kaplan-Meier analysis showed a TLR-free survival at 1 and 3 years of 97.2 and 96.1%, respectively.

CONCLUSION

PCI with bp-BES seems to be well tolerated and effective in a large unselected population of diabetic patients. The good results observed were maintained at 3 years of follow-up.

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

BACKGROUND AND AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Cardiovascular Disease Risk Factors in Ghana during the Rural-to-Urban Transition: A Cross-Sectional Study

Populations in sub-Saharan Africa are shifting from rural to increasingly urban. Although the burden of cardiovascular disease is expected to increase with this changing landscape, few large studies have assessed a wide range of risk factors in urban and rural populations, particularly in West Africa. We conducted a cross-sectional, population-based survey of 3317 participants from Ghana (≥18 years old), of whom 2265 (57% female) were from a mid-sized city (Sunyani, population ~250,000) and 1052 (55% female) were from surrounding villages (populations <5000). We measured canonical cardiovascular disease risk factors (BMI, blood pressure, fasting glucose, lipids) and fibrinolytic markers (PAI-1 and t-PA), and assessed how their distributions and related clinical outcomes (including obesity, hypertension and diabetes) varied with urban residence and sex. Urban residence was strongly associated with obesity (OR: 7.8, 95% CI: 5.3–11.3), diabetes (OR 3.6, 95% CI: 2.3–5.7), and hypertension (OR 3.2, 95% CI: 2.6–4.0). Among the quantitative measures, most affected were total cholesterol (+0.81 standard deviations, 95% CI 0.73–0.88), LDL cholesterol (+0.89, 95% CI: 0.79–0.99), and t-PA (+0.56, 95% CI: 0.48–0.63). Triglycerides and HDL cholesterol profiles were similarly poor in both urban and rural environments, but significantly worse among rural participants after BMI-adjustment. For most of the risk factors, the strength of the association with urban residence did not vary with sex. Obesity was a major exception, with urban women at particularly high risk (26% age-standardized prevalence) compared to urban men (7%). Overall, urban residents had substantially worse cardiovascular risk profiles, with some risk factors at levels typically seen in the developed world.

Everolimus Eluting Stents Versus Coronary Artery Bypass Graft Surgery for Patients With Diabetes Mellitus and Multivessel Disease

BACKGROUND

In patients with diabetes mellitus and multivessel disease, coronary artery bypass graft surgery and percutaneous coronary intervention are treatment options. However, there is paucity of data comparing coronary artery bypass graft surgery against newer generation stents.

METHODS AND RESULTS

Patients included in the New York State registries who had diabetes mellitus and underwent isolated coronary artery bypass graft surgery or percutaneous coronary intervention with everolimus eluting stent (EES) for multivessel disease were included. Propensity score matching was used to assemble a cohort with similar baseline characteristics. The primary outcome was all-cause mortality. Secondary outcomes were myocardial infarction (MI), stroke, and repeat revascularization. Short-term (within 30 days) and long-term outcomes were evaluated. Among 16,089 patients with diabetes mellitus and multivessel disease, 8096 patients with similar propensity scores were included. At short-term, EES was associated with a lower risk of death (hazard ratio [HR] =0.58; 95% confidence interval [CI], 0.34-0.98; P=0.04) and stroke (HR=0.14; 95% CI, 0.06-0.30; P<0.0001) but higher risk of MI (HR=2.44; 95% CI, 1.13-5.31; P=0.02). At long-term, EES was associated with a similar risk of death (425 [10.50%] versus 414 [10.23%] events; HR=1.12; 95% CI, 0.96-1.30; P=0.16), a lower risk of stroke (118 [2.92%] versus 157 [3.88%] events; HR=0.76; 95% CI, 0.58-0.99; P=0.04) but a higher risk of MI (260 [6.42%] versus 166 [4.10%] events; HR=1.64; 95% CI, 1.32-2.04; P<0.0001) and repeat revascularization (889 [21.96%] versus 421 [10.40%] events; HR=2.42; 95% CI, 2.12-2.76; P<0.0001). The higher risk of MI was not seen in the subgroup of EES patients who underwent complete revascularization (HR=1.37; 95% CI, 0.76-2.47; P=0.30).

CONCLUSIONS

In patients with diabetes mellitus and multivessel disease, EES was associated with lower upfront risk of death and stroke when compared with coronary artery bypass graft surgery. However, at long-term, EES was associated with similar risk of death, a higher risk of MI (in those with incomplete revascularization), and repeat revascularization but a lower risk of stroke.

Comparison of lipid parameters to predict cardiovascular events in Japanese mild-to-moderate hypercholesterolemic patients with and without type 2 diabetes: Subanalysis of the MEGA study

AIMS

To determine whether specific lipid parameters are better predictors of cardiovascular disease (CVD) in Japanese mild-to-moderate hypercholesterolemic patients with and without diabetes.

METHODS

Mildly or moderately hypercholesterolemic patients with no history of CVD received diet therapy or diet therapy plus pravastatin. In this post-hoc subanalysis, 5-year data from 3170 patients (668 diabetes, 2502 non-diabetes) on diet therapy alone were used to compare lipid parameters as predictors of CVD. We examined the data by tertiles, using hazard ratio (HR) per one-standard deviation (SD) increment (decrease for high-density lipoprotein cholesterol, HDL-C), χ(2) value, receiver operating characteristic curve analysis, and spline analysis.

RESULTS

In mild-to-moderate hypercholesterolemic patients with diabetes, increased total cholesterol (TC)/HDL-C, low-density lipoprotein cholesterol (LDL-C)/HDL-C and decreased HDL-C were strongly associated with increased incidence of CVD (tertile analysis). In non-diabetes, increased non-HDL-C, and LDL-C/HDL-C were significantly associated with increased incidence of CVD. A one-SD decrease in HDL-C and a one-SD increment in non-HDL-C, TC/HDL-C, and LDL-C/HDL-C were significantly associated with increased HRs for CVD in both diabetes and non-diabetes. Linear CVD risk increases were found for non-HDL-C in diabetes and for non-HDL-C and HDL-C in non-diabetes (spline analysis).

CONCLUSIONS

In mild-to-moderate hypercholesterolemia, CVD risk prediction by stratifications of single or combination of traditional lipid parameter values illustrates various patterns. Parameters including HDL-C are better predictors of cardiovascular risk than only using TC or LDL-C alone. Non-HDL-C could be the most useful lipid parameter to assess CVD risk, considering it is easy to calculate and less affected by food intake.

Coronary atherosclerosis in outlier subjects at the opposite extremes of traditional risk factors: Rationale and preliminary results of the Coronary Atherosclerosis in outlier subjects: Protective and novel Individual Risk factors Evaluation (CAPIRE) study

Although it is generally accepted that cardiac ischemic events develop when coronary atherosclerosis (coronary artery disease [CAD]) has reached a critical threshold, this is true only to a first approximation. Indeed, there are patients with severe CAD who do not develop ischemic events; conversely, at the other extreme, individuals with minimal CAD may do. Similar exceptions to this paradigm include patients with diffuse CAD with a low risk factor (RF) profile and others with multiple RFs who develop only mild or no CAD. Therefore, the CAPIRE project was designed to investigate whether the specific study of these extreme outlier populations could provide clues for identification of yet unknown risk or protective factors for CAD and ischemic events. In the CAPIRE study, 481 subjects without previous symptoms or history of ischemic heart disease and normal left ventricular systolic function undergoing coronary computed tomography angiography have been selected based on coronary computed tomography angiography findings and cardiovascular RF profile. Therefore, in the whole population, 2 extreme outlier populations have been identified: (1) subjects with no CAD despite multiple RFs, and (2) at the opposite extreme, subjects with diffuse CAD despite a low-risk profile. Each subject has been characterized by clinical, anatomical imaging variables of CAD and baseline circulating biomarkers. Blood samples were collected and stored in a biological bank for further advanced investigations. The project is designed as a prospective, observational, international multicenter study with an initial cross-sectional analysis of clinical, imaging, and biomolecular variables in the selected groups and a longitudinal 5-year follow-up.

Chronic Inflammatory Diseases and Endothelial Dysfunction

Chronic inflammatory diseases are associated with increases in cardiovascular diseases (CVD) and subclinical atherosclerosis as well as early-stage endothelial dysfunction screening using the FMD method (Flow Mediated Dilation). This phenomenon, referred to as accelerated pathological remodeling of arterial wall, could be attributed to traditional risk factors associated with atherosclerosis. Several new non-invasive techniques have been used to study arterial wall's structural and functional alterations. These techniques (based of Radio Frequency, RF) allow for an assessment of artery age through calculations of intima-media thickness (RF- QIMT), pulse wave rate (RF- QAS) and endothelial dysfunction degree (FMD). The inflammatory and autoimmune diseases should now be considered as new cardiovascular risk factors, result of the major consequences of oxidative stress and RAS (Renin Angiotensin System) imbalance associated with the deleterious effect of known risk factors that lead to the alteration of the arterial wall. Inflammation plays a key role in all stages of the formation of vascular lesions maintained and exacerbated by the risk factors. The consequence of chronic inflammation is endothelial dysfunction that sets in and we can define it as an integrated marker of the damage to arterial walls by classic risk factors. The atherosclerosis, which develops among these patients, is the main cause for cardiovascular morbi-mortality and uncontrolled chronic biological inflammation, which quickly favors endothelial dysfunction. These inflammatory and autoimmune diseases should now be considered as new cardiovascular risk factors.

Smoking in Relation to Coronary Atherosclerotic Plaque Burden, Volume and Composition on Intravascular Ultrasound

Background

This study aimed to evaluate the relationship between cigarette smoking and coronary atherosclerotic burden, volume and composition as determined in-vivo by grayscale and virtual histology (VH) intravascular ultrasound (IVUS).

Methods and Results

Between 2008 and 2011, (VH-)IVUS of a non-culprit coronary artery was performed in 581 patients undergoing coronary angiography. To account for differences in baseline characteristics, current smokers were matched to never smokers by age, gender and indication for catheterization, resulting in 280 patients available for further analysis. Coronary atherosclerotic plaque volume, burden, composition (fibrous, fibro-fatty, dense calcium and necrotic core) and high-risk lesions (VH-IVUS derived thin-cap fibroatheroma (TCFA), plaque burden ≥70%, minimal luminal area ≤4.0 mm²) were assessed. Cigarette smoking showed a tendency towards higher coronary plaque burden (mean±SD, 38.6±12.5% in current versus 36.4±11.0% in never smokers, p = 0.080; and odds ratio (OR) of current smoking for plaque burden above versus below the median 1.69 (1.04–2.75), p = 0.033). This effect was driven by an association in patients presenting with an acute coronary syndrome (ACS) (current smokers, plaque burden 38.3±12.8% versus never smokers, plaque burden 35.0±11.2%, p = 0.049; OR 1.88 (1.02–3.44), p = 0.042). Fibrous tissue tended to be lower in current smokers (mean±SD, 57.7±10.5% versus 60.4±12.6%, p = 0.050) and fibro-fatty tissue was higher in current smokers (median[IQR], 9.6[6.0–13.7]% versus 8.6[5.8–12.2]%, p = 0.039). However, differences in percentage necrotic core and dense calcium could not be demonstrated. Also, no differences were found with regard to high-risk lesions.

Conclusions

An association between smoking and degree of coronary atherosclerosis was present in patients undergoing coronary angiography who presented with ACS. Although smoking was associated with higher fibro-fatty percentage, no associations could be demonstrated with percentage necrotic core, nor with VH-IVUS derived TCFA lesions. Since the magnitude of the differences in both degree and composition of atherosclerosis was modest, clinical relevance of the findings may be questioned.

Relationships between components of metabolic syndrome and coronary intravascular ultrasound atherosclerosis measures in women without obstructive coronary artery disease: the NHLBI-Sponsored Women's Ischemia Syndrome Evaluation Study

OBJECTIVE

In women, metabolic syndrome (MetS) is associated with higher risk of ischemic heart disease-related adverse outcomes versus individual components. We examined the relationship of MetS to subclinical coronary atherosclerosis.

METHODS

Women (n = 100) undergoing coronary angiography for suspected ischemia but without obstructive coronary artery disease (CAD) underwent intravascular ultrasound (IVUS) of a segment of the left coronary artery. A core lab, masked to other findings, assessed IVUS measures and normalized volume measures to pull-back length. MetS [defined using ATPIII criteria (fasting glucose ≥ 100 mg/dl per revised NCEP guideline)] and its components were entered into multiple regression models to assess associations with IVUS measures.

RESULTS

Detailed IVUS measurements were available in 87 women. Mean age was 54 ± 10 years, 36% had MetS, and 78% had atheroma. Comparing women with MetS versus without MetS, significant differences were observed for seven IVUS atherosclerosis measures, but were not significant after adjusting for the MetS components. Systolic blood pressure and waist circumference components remained independently positively associated with the IVUS measures after adjusting for age, diabetes, CAD family history, dyslipidemia, smoking, and hormone replacement.

CONCLUSION

In women with signs and symptoms of ischemia and no obstructive CAD, MetS is associated with coronary atherosclerosis presence and severity. However, these associations appear largely driven by components of waist circumference and systolic blood pressure versus MetS cluster. This supports the concept that MetS is a convenient clustering of risk factors rather than an independent risk predictor, and emphasizes that the critical factors for coronary atherosclerosis are potentially modifiable.

Regression of coronary atherosclerosis: Current evidence and future perspectives

Coronary atherosclerosis has been considered a chronic disease characterized by ongoing progression in response to systemic risk factors and local pro-atherogenic stimuli. As our understanding of the pathobiological mechanisms implicated in atherogenesis and plaque progression is evolving, effective treatment strategies have been developed that led to substantial reduction of the clinical manifestations and acute complications of coronary atherosclerotic disease. More recently, intracoronary imaging modalities have enabled detailed in vivo quantification and characterization of coronary atherosclerotic plaque, serial evaluation of atherosclerotic changes over time, and assessment of vascular responses to effective anti-atherosclerotic medications. The use of intracoronary imaging modalities has demonstrated that intensive lipid lowering can halt plaque progression and may even result in regression of coronary atheroma when the highest doses of the most potent statins are used. While current evidence indicates the feasibility of atheroma regression and of reversal of presumed high-risk plaque characteristics in response to intensive anti-atherosclerotic therapies, these changes of plaque size and composition are modest and their clinical implications remain largely elusive. Growing interest has focused on achieving more pronounced regression of coronary plaque using novel anti-atherosclerotic medications, and more importantly on elucidating ways toward clinical translation of favorable changes of plaque anatomy into more favorable clinical outcomes for our patients.

Age-related effects of smoking on coronary artery disease assessed by gray scale and virtual histology intravascular ultrasound

Although smoking is a risk factor for coronary atherosclerosis, the age-related impact on lesion morphology has not been studied. The aim of this study was to assess the age-related impact of smoking on the extent of atherosclerosis and arterial remodeling. In Providing Regional Observations to Study Predictors of Events in the Coronary Tree, 687 patients with acute coronary syndrome underwent 3-vessel gray scale and virtual histology intravascular ultrasound imaging of 3,185 nonculprit lesions. In 207 patients ≤65 years, current (smoking within 1 month) and former (no smoking for >1 month) smokers showed significantly smaller normalized volumes of external elastic membrane (EEM), lumen, and P + M (plaque + media) compared with nonsmokers. At the minimal lumen area site, current and former smokers had significantly smaller EEM, lumen, and P + M areas than nonsmokers. Conversely, in 480 patients >65 years, current smokers had greater normalized P + M volumes than nonsmokers with no difference in normalized EEM or lumen volumes. Finally, in patients >65 years (but not in patients ≤65 years), current smokers showed more plaque ruptures (4.7% vs 1.8%, p = 0.05) and echolucent plaques (8.3% vs 3.9%, p = 0.05) compared with nonsmokers. On multivariable analysis, a history of smoking (combining current and former smoking) predicted smaller normalized EEM volumes compared with nonsmokers ≤65 years. In conclusion, in patients ≤65 years, but not in patients >65 years, smoking had a vascular constrictive effect that contributed to severe luminal stenosis. Conversely, smokers >65 years had more plaque with greater plaque instability.

Using a Systems Pharmacology Approach to Study the Effect of Statins on the Early Stage of Atherosclerosis in Humans

More than 100,000 people have participated in controlled trials of statins (lowering cholesterol drugs) since the introduction of lovastatin in the 1980s. Meta-analyses of this data have shown that statins have a beneficial effect on treated groups compared to control groups, reducing cardiovascular risk. Inhibiting the HMG-CoA reductase in the liver, statins can reduce cholesterol levels, thus reducing LDL levels in circulation. Published data from intravascular ultrasound studies (IVUS) was used in this work to develop and validate a unique integrative system model; this consisted of analyzing control groups from two randomized controlled statins trials (24/97 subjects respectively), one treated group (40 subjects, simvastatin trial), and 27 male subjects (simvastatin, pharmacokinetic study). The model allows to simulate the pharmacokinetics of statins and its effect on the dynamics of lipoproteins (e.g., LDL) and the inflammatory pathway while simultaneously exploring the effect of flow-related variables (e.g., wall shear stress) on atherosclerosis progression.

Global coronary flow reserve is associated with adverse cardiovascular events independently of luminal angiographic severity and modifies the effect of early revascularization

BACKGROUND

Coronary flow reserve (CFR), an integrated measure of focal, diffuse, and small-vessel coronary artery disease (CAD), identifies patients at risk for cardiac death. We sought to determine the association between CFR, angiographic CAD, and cardiovascular outcomes.

METHODS AND RESULTS

Consecutive patients (n=329) referred for invasive coronary angiography after stress testing with myocardial perfusion positron emission tomography were followed (median 3.1 years) for cardiovascular death and heart failure admission. The extent and severity of angiographic disease were estimated with the use of the CAD prognostic index, and CFR was measured noninvasively by positron emission tomography. A modest inverse correlation was seen between CFR and CAD prognostic index (r=-0.26; P<0.0001). After adjustment for clinical risk score, ejection fraction, global ischemia, and early revascularization, CFR and CAD prognostic index were independently associated with events (hazard ratio for unit decrease in CFR, 2.02; 95% confidence interval, 1.20-3.40; P=0.008; hazard ratio for 10-U increase in CAD prognostic index, 1.17; 95% confidence interval, 1.01-1.34; P=0.032). Subjects with low CFR experienced rates of events similar to those of subjects with high angiographic scores, and those with low CFR or high CAD prognostic index showed the highest risk of events (P=0.001). There was a significant interaction (P=0.039) between CFR and early revascularization by coronary artery bypass grafting, such that patients with low CFR who underwent coronary artery bypass grafting, but not percutaneous coronary intervention, experienced event rates comparable to those with preserved CFR, independently of revascularization.

CONCLUSIONS

CFR was associated with outcomes independently of angiographic CAD and modified the effect of early revascularization. Diffuse atherosclerosis and associated microvascular dysfunction may contribute to the pathophysiology of cardiovascular death and heart failure, and impact the outcomes of revascularization.

Subclinical cardiovascular disease in type 2 diabetes mellitus: To screen or not to screen

The prevalence of type 2 diabetes mellitus (T2DM) has risen in recent decades, and cardiovascular disease remains the leading cause of death in this population. Several clinical trials have demonstrated the benefit of tight control of risk factors on the incidence and mortality of cardiovascular disease. However, in clinical practice, few patients achieve the therapeutic goals. The current diagnostic procedures for subclinical cardiovascular disease in T2DM patients have not been shown to improve prognosis or mortality, probably because they do not categorize cardiovascular risk. Thus, clinical practice guidelines do not systematically recommend screening for subclinical atherosclerosis in these patients, although it is known that patients with extra-coronary atherosclerosis, microangiopathy and poorly-controlled cardiovascular risk factors are at high risk for cardiovascular disease. Improvements in the reliability of diagnostic tests, with fewer side effects and better cost efficiency, may better help to stratify cardiovascular risk in this group of patients, and further evaluation on this topic should be considered.

Impact of cigarette smoking on extent of coronary artery disease and prognosis of patients with non-ST-segment elevation acute coronary syndromes: an analysis from the ACUITY Trial (Acute Catheterization and Urgent Intervention Triage Strategy)

OBJECTIVES

This study sought to evaluate the short- and long-term outcomes for smokers with non-ST-segment elevation acute coronary syndromes (NSTE-ACS).

BACKGROUND

Smoking has been associated with the "paradox" of reduced mortality after acute myocardial infarction (MI). This is thought to be due to favorable baseline characteristics and less diffuse coronary artery disease (CAD) among smokers.

METHODS

In the ACUITY (Acute Catheterization and Urgent Intervention Triage Strategy) trial, 13,819 patients (29.1% smokers) with moderate- to high-risk NSTE-ACS underwent angiography and, if indicated, revascularization.

RESULTS

Smokers were significantly younger and had fewer comorbidities than nonsmokers. Incidence of death and MI were comparable at 30 days, although smokers had significantly reduced risks of 30-day major bleeding (hazard ratio [HR]: 0.80, 95% confidence interval [CI]: 0.67 to 0.96; p = 0.016) and 1-year mortality (HR: 0.797, 95% CI: 0.65 to 0.97; p = 0.027). After correction for baseline and clinical differences, smoking was no longer predictive of major bleeding (odds ratio: 1.06, 95% CI: 0.86 to 1.32; p = 0.56) and was associated with higher 1-year mortality (HR: 1.37, 95% CI: 1.07 to 1.7; p = 0.013). This pattern of reversed risk after multivariable correction held true for those smokers requiring percutaneous coronary intervention. Core laboratory angiographic analysis showed that smokers and nonsmokers were comparable in terms of the extent of CAD, Thrombolysis In Myocardial Infarction flow, myocardial blush, and the presence of thrombi.

CONCLUSIONS

In contrast to the paradox previously described in ST-segment elevation MI, our analysis finds smoking to be an independent predictor of higher 1-year mortality in patients presenting with NSTE-ACS, and our angiographic study demonstrates CAD in smokers that is comparable to that in nonsmokers but evident ∼1 decade earlier. (Acute Catheterization and Urgent Intervention Triage Strategy [ACUITY]; NCT00093158).

Exploring the natural history of atherosclerosis with intravascular ultrasound

Intravascular ultrasound has emerged as the preferred imaging modality for the characterization of atherosclerotic plaque within the coronary arteries. Ultrasonic imaging reveals the presence of more extensive atheroma than suggested by conventional angiography in patients with coronary artery disease. The ability to precisely quantify atheroma volume in an arterial segment at different time points provides the unique opportunity to investigate the factors that influence the natural history of atheroma progression. Accordingly, serial intravascular ultrasound has been incorporated into a number of clinical trials that have evaluated the impact of medical therapies that modify established risk factors and novel pathological targets. This article will review the increasing role of imaging modalities in the assessment of atherosclerosis and factors that influence its natural history.

Synergistic effect of local endothelial shear stress and systemic hypercholesterolemia on coronary atherosclerotic plaque progression and composition in pigs

BACKGROUND

Systemic risk factors and local hemodynamic factors both contribute to coronary atherosclerosis, but their possibly synergistic inter-relationship remains unknown. The purpose of this natural history study was to investigate the combined in-vivo effect of varying levels of systemic hypercholesterolemia and local endothelial shear stress (ESS) on subsequent plaque progression and histological composition.

METHODS

Diabetic, hyperlipidemic swine with higher systemic total cholesterol (TC) (n=4) and relatively lower TC levels (n=5) underwent three-vessel intravascular ultrasound (IVUS) at 3-5 consecutive time-points in-vivo. ESS was calculated serially using computational fluid dynamics. 3-D reconstructed coronary arteries were divided into 3mm-long segments (n=595), which were stratified according to higher vs. relatively lower TC and low (<1.2Pa) vs. higher local ESS (≥1.2Pa). Arteries were harvested at 9months, and a subset of segments (n=114) underwent histopathologic analyses.

RESULTS

Change of plaque volume (ΔPV) by IVUS over time was most pronounced in low-ESS segments from higher-TC animals. Notably, higher-ESS segments from higher-TC animals had greater ΔPV compared to low-ESS segments from lower-TC animals (p<0.001). The time-averaged ESS in segments that resulted in significant plaque increased with increasing TC levels (slope: 0.24Pa/100mg/dl; r=0.80; p<0.01). At follow-up, low-ESS segments from higher-TC animals had the highest mRNA levels of lipoprotein receptors and inflammatory mediators and, consequently, the greatest lipid accumulation and inflammation.

CONCLUSIONS

This study redefines the principle concept that "low" ESS promotes coronary plaque growth and vulnerability by demonstrating that: (i.) the pro-atherogenic threshold of low ESS is not uniform, but cholesterol-dependent; and (ii.) the atherogenic effects of local low ESS are amplified, and the athero-protective effects of higher ESS may be outweighed, by increasing cholesterol levels. Intense hypercholesterolemia and very low ESS are synergistic in favoring rapid atheroma progression and high-risk composition.

Hypo- and hyperglycemia impair endothelial cell actin alignment and nitric oxide synthase activation in response to shear stress

Uncontrolled blood glucose in people with diabetes correlates with endothelial cell dysfunction, which contributes to accelerated atherosclerosis and subsequent myocardial infarction, stroke, and peripheral vascular disease. In vitro, both low and high glucose induce endothelial cell dysfunction; however the effect of altered glucose on endothelial cell fluid flow response has not been studied. This is critical to understanding diabetic cardiovascular disease, since endothelial cell cytoskeletal alignment and nitric oxide release in response to shear stress from flowing blood are atheroprotective. In this study, porcine aortic endothelial cells were cultured in 1, 5.55, and 33 mM D-glucose medium (low, normal, and high glucose) and exposed to 20 dynes/cm² shear stress for up to 24 hours in a parallel plate flow chamber. Actin alignment and endothelial nitric oxide synthase phosphorylation increased with shear stress for cells in normal glucose, but not cells in low and high glucose. Both low and high glucose elevated protein kinase C (PKC) levels; however PKC blockade only restored actin alignment in high glucose cells. Cells in low glucose instead released vascular endothelial growth factor (VEGF), which translocated β-catenin away from the cell membrane and disabled the mechanosensory complex. Blocking VEGF in low glucose restored cell actin alignment in response to shear stress. These data suggest that low and high glucose alter endothelial cell alignment and nitric oxide production in response to shear stress through different mechanisms.

Discordant association of C-reactive protein with clinical events and coronary luminal narrowing in postmenopausal women: data from the Women's Angiographic Vitamin and Estrogen (WAVE) study

BACKGROUND

The incidence of cardiovascular events had been shown to be associated with C-reactive protein (CRP). However, it is unclear that the cardiovascular risk associated with CRP is due to progressive coronary narrowing or to other factors such as formation of unstable plaque. This study was designed to determine the effect of baseline CRP on cardiovascular events and on the progression of atherosclerotic narrowing among 423 postmenopausal women with angiographic stenosis between 15% and 75%.

HYPOTHESIS

Baseline CRP levels may affect cardiovascular events and progression of atherosclerotic coronary artery narrowing among postmenopausal women.

METHODS

Baseline and follow-up (2.8 years) angiographic data were analyzed among 320 women. Women were stratified into 4 quartiles according to baseline CRP levels. The changes in lumen diameter and clinical events in each quartile were compared.

RESULTS

The annualized changes in minimal and average lumen diameter in diseased and nondiseased coronary segments were not significantly associated with baseline CRP levels. The composite end point of all-cause mortality and myocardial infarction (MI) increased from 3% (3/107) in the first CRP quartile to 14% (14/98) in fourth CRP quartile (P < 0.001). Similar results were found for cardiovascular death and MI (increased from 1% (2/107) in the first quartile to 11% (11/98) in fourth quartile). The difference remained significant even after adjustment for baseline differences and cardiovascular risk factors.

CONCLUSIONS

Higher baseline CRP was associated with increased risk of clinical events but was not associated with annualized change in luminal diameters. Thus, increased risk of adverse events among patients with higher baseline CRP events was independent of progression of atherosclerosis as measured by change in minimal or average luminal diameter.

Screening for subclinical atherosclerosis by noninvasive methods in asymptomatic patients with risk factors

Atherosclerosis is a leading cause of cardiovascular death due to the increasing prevalence of the disease and the impact of risk factors such as diabetes, obesity or smoking. Sudden cardiac death is the primary consequence of coronary artery disease in 50% of men and 64% of women. Currently the only available strategy to reduce mortality in the at-risk population is primary prevention; the target population must receive screening for atherosclerosis. The value of screening for subclinical atherosclerosis is still relevant, it has become standard clinical practice with the emergence of new noninvasive techniques (radio frequency [RF] measurement of intima-media thickness [RFQIMT] and arterial stiffness [RFQAS], and flow-mediated vasodilatation [FMV]), which have been used by our team since 2007 and are based on detection marker integrators which reflect the deleterious effect of risk factors on arterial remodeling before the onset of clinical events. These techniques allow the study of values according to age and diagnosis of the pathological value, the thickness of the intima media (RFQIMT), the speed of the pulse wave (RFQAS), and the degree of endothelial dysfunction (FMV). This screening is justified in asymptomatic patients with cardiovascular risk factors (hypertension, diabetes, obesity, dyslipidemia, and tobacco smoking). Studies conducted by RF coupled with two-dimensional echo since 2007 have led to a more detailed analysis of the state of the arterial wall. The various examinations allow an assessment of the degree of subclinical atherosclerosis and its impact on arterial remodeling and endothelial function. The use of noninvasive imaging in screening and early detection of subclinical atherosclerosis is reliable and reproducible and allows us to assess the susceptibility of our patients with risk factors and ensures better monitoring of atherosclerosis, thus reducing the occurrence of cardiovascular events in the long term.

Intravascular ultrasound comparison of left main coronary artery disease between white and Asian patients

We assessed the ethnic differences in coronary atherosclerosis lesion morphology between white and Asian patients. Our hypothesis was that left main coronary artery (LMCA) disease was more focal and less complex in Asian than in Western white patients. We studied 99 Asian patients (Japan and South Korea) and 99 matched control United States white patients with a stable clinical presentation and >30% LMCA angiographic diameter stenosis by visual estimation. The matching parameters included age, gender, and diabetes mellitus. The vessel and lumen areas and calcium arc were analyzed every 0.5 mm and normalized for analysis length. Overall, 75.1% of the patients were men and 34.1% had diabetes. The patient age was 68.0 ± 10 years, with no differences between the Asian and white patients. The Asian patients had a lower prevalence of hyperlipidemia than the white patients (41.4% vs 81.8%; p <0.0001) and were smaller in size, and the white patients were more obese (body mass index 23.7 ± 2.6 vs 27.6 ± 4.1 kg/m(2), p <0.0001). The Asian patients had a smaller lumen area (5.2 ± 1.8 vs 6.2 ± 14 mm(2); p <0.0001), larger vessel area (20.0 ± 4.9 vs 18.4 ± 4.4 mm(2); p <0.0001), and larger plaque burden (72 ± 10 vs 64 ± 12%: p <0.0001) at the minimum lumen site and over the entire LMCA length. The white patients had more calcification, whether assessed by the maximum arc (82° ± 74° vs 49° ± 45°; p <0.0001) or total length (3.6 ± 3.2 vs 2.1 ± 2.1 mm; p <0.0001). In conclusion, after matching well-known risk factors, there appeared to be ethnic differences in coronary atherosclerosis morphology between Asian and white patients, at least as it affected LMCA morphology.