Plaque characterisation by Virtual Histology intravascular ultrasound analysis in patients with type 2 diabetes

Comparison of Atherosclerotic Plaque Compositions in Diabetic and Non-diabetic Patients

INTRODUCTION

Diabetes mellitus is one of the major risk factors for coronary artery disease. Intravascular ultrasound (IVUS) imaging has an important role in the evaluation of atherosclerotic coronary artery disease. The aim of the study was to investigate the potential link between diabetes mellitus and plaque vulnerability in patients with coronary artery disease.

METHODS

In total, 26 patients with acute coronary syndrome (eight with diabetes mellitus) and 34 with stable angina pectoris (16 with diabetes mellitus) constituted the study population. Patients underwent IVUS ultrasound and virtual histology (VH)-IVUS imaging during routine diagnostic catheterization procedures. A total of 70 plaques in 60 patients were examined.

RESULTS

Patients with diabetes mellitus had a significantly greater percentage of fibrofatty components in the minimal lumen area (MLA) (17 ± 12 in diabetics; 12 ± 6 in non-diabetics; p=0.06). Thin-cap fibroatheromas were more frequent in patients with diabetes mellitus (72% versus 45%; p=0.012). There was a positive correlation between the presence of attenuated plaque and hemoglobin A1C (HbA1c) levels as well (7.09 ± 1.66 versus 6.02 ± 1.00; p=0.011). Patients with HbA1C ≥7.5% also had the highest prevalence of attenuated plaque.

CONCLUSION

As shown by VH-IVUS, the prevalence of vulnerable plaques in patients with diabetes mellitus was much higher than that in non-diabetic patients. The presence of attenuated plaque detected in grayscale intravascular ultrasonography was associated with high HbA1C levels in diabetic patients. Diabetes mellitus may cause cardiovascular vulnerability by changing the plaque morphology.

Melatonin ameliorates myocardial infarction in obese diabetic individuals: The possible involvement of macrophage apoptotic factors

In recent days, the hike in obesity-mediated epidemics across the globe and the prevalence of obesity-induced cardiovascular disease has become one of the chief grounds for morbidity and mortality. This epidemic-driven detrimental events in the cardiac tissues start with the altered distribution and metabolism pattern of high-density lipoprotein and low-density lipoprotein (LDL) leading to cholesterol (oxidized LDL) deposition on the arterial wall and atherosclerotic plaque generation, followed by vascular spasms and infarction. Subsequently, obesity-triggered metabolic malfunctions induce free radical generation which may further trigger pro-inflammatory signaling and nuclear factor kappa-light-chain-enhancer of activated B cells transcriptional factor, thus inducing interferon-gamma, tumor necrosis factor-alpha, and inducible nitric oxide synthase. This terrifying cardiomyopathy can be further aggravated in type 2 diabetes mellitus, thereby making obese diabetic patients prone toward the development of myocardial infarction (MI) or stroke in comparison to their nondiabetic counterparts. The accelerated oxidative stress and pro-inflammatory response induced cardiomyocyte hypertrophy, followed by apoptosis in obese diabetic individuals, causing progression of athero-thrombotic vascular disease. Being an efficient antioxidative and anti-inflammatory indolamine, melatonin effectively inhibits lipid peroxidation, pro-inflammatory reactions, thereby resolving free radical-induced myocardial damages along with maintaining antioxidant reservoir to preserve cardiovascular integrity. Prolonged melatonin treatment maintains balanced body weight and serum total cholesterol concentration by inhibiting cholesterol synthesis and promoting cholesterol catabolism. Additionally, melatonin promotes macrophage polarization toward the anti-inflammatory state, providing a proper shield during the recovery period. Therefore, the protective role of melatonin in maintaining the lipid metabolism homeostasis and blocking the atherosclerotic plaque rupture could be targeted as the possible therapeutic strategy for the management of obesity-induced acute MI. This review aimed at orchestrating the efficacy of melatonin in ameliorating irrevocable oxidative cardiovascular damage induced by the obesity-diabetes correlation.

Coronary Artery Lesion Lipid Content and Plaque Burden in Diabetic and Nondiabetic Patients: PROSPECT II

BACKGROUND

Patients with diabetes have increased rates of major adverse cardiac events (MACEs). We hypothesized that this is explained by diabetes-associated differences in coronary plaque morphology and lipid content.

METHODS

In PROSPECT II (Providing Regional Observations to Study Predictors of Events in the Coronary Tree), 898 patients with acute myocardial infarction with or without ST-segment elevation underwent 3-vessel quantitative coronary angiography and coregistered near-infrared spectroscopy and intravascular ultrasound imaging after successful percutaneous coronary intervention. Subsequent MACEs were adjudicated to either treated culprit lesions or untreated nonculprit lesions. This substudy stratified patients by diabetes status and assessed baseline culprit and nonculprit prevalence of high-risk plaque characteristics defined as maximum plaque burden ≥70% and maximum lipid core burden index ≥324.7. Separate covariate-adjusted multivariable models were performed to identify whether diabetes was associated with nonculprit lesion-related MACEs and high-risk plaque characteristics.

RESULTS

Diabetes was present in 109 of 898 patients (12.1%). During a median 3.7-year follow-up, MACEs occurred more frequently in patients with versus without diabetes (20.1% versus 13.5% [odds ratio (OR), 1.94 (95% CI, 1.14-3.30)]), primarily attributable to increased risk of myocardial infarction related to culprit lesion restenosis (4.3% versus 1.1% [OR, 3.78 (95% CI, 1.12-12.77)]) and nonculprit lesion-related spontaneous myocardial infarction (9.3% versus 3.8% [OR, 2.74 (95% CI, 1.25-6.04)]). However, baseline prevalence of high-risk plaque characteristics was similar for patients with versus without diabetes concerning culprit (maximum plaque burden ≥70%: 90% versus 93%, P=0.34; maximum lipid core burden index ≥324.7: 66% versus 70%, P=0.49) and nonculprit lesions (maximum plaque burden ≥70%: 23% versus 22%, P=0.37; maximum lipid core burden index ≥324.7: 26% versus 24%, P=0.47). In multivariable models, diabetes was associated with MACEs in nonculprit lesions (adjusted OR, 2.47 [95% CI, 1.21-5.04]) but not with prevalence of high-risk plaque characteristics (adjusted OR, 1.21 [95% CI, 0.86-1.69]).

CONCLUSIONS

Among patients with recent myocardial infarction, both treated and untreated lesions contributed to the diabetes-associated ≈2-fold increased MACE rate during the 3.7-year follow-up. Diabetes-related plaque characteristics that might underlie this increased risk were not identified by multimodality imaging.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02171065.

The comparative short-term efficacy and safety of drug-coated balloon vs. drug-eluting stent for treating small-vessel coronary artery lesions in diabetic patients

Purpose

This meta-analysis aimed to explore the comparative short-term efficacy and safety of drug-coated balloon (DCB) vs. drug-eluting stent (DES) for treating small-vessel coronary artery lesions in diabetic patients.

Methods

We searched PubMed, EMBASE, the Cochrane Library, and China National Knowledgement Infrastructure (CNKI) for retrieving relevant studies regarding the comparison of DCB with DES in treating small-vessel coronary artery lesions in diabetic patients until May 31, 2022. Two independent authors screened study, extracted data, and assessed methodological quality. Then, the meta-analysis was conducted using RevMan software, version 5.4.

Results

We included 6 studies with 847 patients in this meta-analysis. Pooled results showed that DCB was associated with fewer major adverse cardiac events (MACE) [RR, 0.60; 95% confidence interval (CI), 0.39-0.93; p = 0.02], myocardial infarction (MI) (RR, 0.42; 95% CI, 0.19-0.94; p = 0.03), target lesion revascularization (TLR) (RR, 0.24; 95% CI, 0.08-0.69; p < 0.001), target vessel revascularization (TVR) (RR, 0.33; 95% CI, 0.18-0.63; p < 0.001), binary restenosis (RR, 0.27; 95% CI, 0.11-0.68; p = 0.005), and late lumen loss (LLL) [mean difference (MD), -0.31; 95% CI, -0.36 to -0.27; p < 0.001], but was comparable technique success rate, death, minimal lumen diameter (MLD), and net lumen gain (NLG) to DES. There was no difference in long-term outcomes between these two techniques.

Conclusions

This meta-analysis shows that DCB is better than DES in the short-term therapeutic efficacy and safety of small-vessel coronary artery lesions in diabetic patients. However, more studies are required to validate our findings and investigate the long-term effects and safety of DCB.

The clinical impact of serum 1,5-anhydro-D-glucitol levels on coronary artery calcification and adverse outcomes assessed by coronary optical coherence tomography in diabetic patients

Background

Serum 1,5-anhydro-D-glucitol (1,5-AG) is a novel biomarker for short-term glycemic status and postprandial hyperglycemia. The association between serum 1,5-AG levels and coronary artery calcification (CAC) through a quantitative assessment using optical coherence tomography (OCT) is unclear. We aimed to evaluate this association using OCT in patients with diabetes mellitus (DM).

Methods

From June 2016 to December 2019, we prospectively enrolled 256 patients who underwent OCT-guided percutaneous coronary intervention (PCI). Half of the patients had diabetes. Patients were followed up for a mean period of 1.8 ± 0.8 years (median: 2.2 years). The relative calcium index and relative lipid core index measured by quantitative OCT analysis were used to evaluate the intra-plaque calcium and lipid levels of culprit plaques. We also analyzed the correlation between serum 1,5-AG levels and long-term major adverse cardiovascular events.

Results

Serum 1,5-AG levels were significantly lower in diabetic patients than in non-diabetic patients (DM vs. non-DM: 55.6 ± 27.9 μg/mL vs. 63.7 ± 26.1 μg/mL, p = 0.016), and lower in fibrocalcified lesions than in fibrotic or fibrolipidic lesions (fibrocalcified vs. fibrotic or fibrolipidic: 42.8 ± 19.1 vs. 72.9 ± 25.2 or 66.4 ± 27.5 μg/mL, p &lt; 0.001, respectively). In addition, we found a significant inverse correlation between serum 1,5-AG levels and relative calcium index (r = −0.729, p &lt; 0.001). In multivariate Cox regression analysis, low serum 1,5-AG level was identified as an independent predictor for major adverse cardiovascular events in diabetic patients (p = 0.043), but not in non-diabetic patients (p = 0.748) after adjusting for age and sex.

Conclusion

This study revealed that low serum 1,5-AG levels were associated with an increased risk of CAC as assessed by OCT, especially in diabetic patients. Low serum 1,5-AG levels may predict future major adverse cardiovascular events in diabetic patients undergoing OCT-guided PCI.

Cardiovascular events and atherosclerosis in patients with type 2 diabetes and impaired glucose tolerance -What are the medical treatments to prevent cardiovascular events in such patients?

Type 2 diabetes mellitus (T2DM) and impaired glucose tolerance (IGT) significantly induce advanced coronary artery disease and systemic atherosclerosis. Thus, T2DM and IGT are traditional risk factors of cardiovascular disease (CVD). On the other hand, acute coronary syndrome is frequently caused by the rupture of coronary atherosclerotic plaques, which reduces patients' quality of life and may result in death. To date, many trials have sought to identify ways to determine the coronary plaque volume and its vulnerability, and many studies have demonstrated that some specific antihyperglycemic agents may prevent coronary or carotid plaque progression, decrease plaque volume, induce plaque stability, and improve clinical outcomes in patients with T2DM and IGT. This article reviews i) the association between coronary or carotid plaques and abnormal glucose tolerance, including T2DM; and ii) the effects of oral antihyperglycemic drugs to improve clinical outcomes and stabilize atherosclerotic plaques in patients with T2DM and IGT.

Relation of renal function to mid-term prognosis of stable angina patients with high- or low-dose pitavastatin treatment: REAL-CAD substudy

BACKGROUND

It has not yet been established whether higher-dose statins have beneficial effects on cardiovascular events in patients with stable coronary artery disease (CAD) and renal dysfunction.

METHODS

The REAL-CAD study is a prospective, multicenter, open-label trial. As a substudy, we categorized patients by an estimated glomerular filtration rate (eGFR) as follows: eGFR ≥60 (n = 7,768); eGFR ≥45 and <60 (n = 3,176); and eGFR <45 mL/Min/1.73 m² (n = 1,164), who were randomized to pitavastatin 4mg or 1mg therapy. The primary endpoint was a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal ischemic stroke, or unstable angina, and was assessed by the log-rank test and Cox proportional hazards model.

RESULTS

The baseline characteristics and medications were largely well-balanced between two groups. The magnitude of low-density lipoprotein cholesterol (LDL-C) reduction at 6 months in high- and low-dose pitavastatin groups was comparable among all eGFR categories. During a median follow-up of 3.9 years, high- compared with low-dose pitavastatin significantly reduced cardiovascular events in patients with eGFR ≥60 (hazard ratio (HR) 0.73; 95% confidence interval (CI) 0.58-0.91; P = .006), and reduced but not significant for patients with eGFR ≥45 and <60 (HR 0.85; 95% CI, 0.63-1.14; P = .27) or eGFR <45 mL/Min/1.73 m² (HR 0.90; 95% CI 0.62-1.33; P = .61). An interaction test of treatment by eGFR category was not significant (P value for interaction = .30).

CONCLUSION

Higher-dose pitavastatin therapy reduced LDL levels and cardiovascular events in stable CAD patients irrespective of eGFR level, although the effect on events appeared to be numerically lower in patients with lower eGFR.

New carotid plaque, but not the progression of intima-media thickness, predicts the progression of high-risk coronary plaque

BACKGROUND

Carotid intima-media thickness (CIMT) is regarded as a controversial risk marker for cardiovascular disease (CVD). We aimed to evaluate the role of CIMT and carotid plaque progression as predictors for the progression of coronary plaque and compositions.

METHODS

In the Garlic 4 study, asymptomatic patients with intermediate CVD risk (Framingham risk score 6-20%) were recruited for a serial carotid ultrasound, and coronary artery calcium score (CAC)/coronary computed tomography angiography (CCTA) studies for subclinical atherosclerosis at a baseline and 1 year. The association between progression of quantitatively measured coronary plaque compositions and the progression of CIMT/carotid plaque was analyzed. A P value <0.05 is considered as statistically significant.

RESULTS

Forty-seven consecutive patients were included. The mean age was 58.5 ± 6.6 years, and 69.1 % were male. New carotid plaque appeared in 34.0 % (n = 16) of participants, and 55.3 % (n = 26) of subjects had coronary plaque progression. In multilinear regression analysis, adjusted by age, gender, and statin use, the development of new carotid plaque was significantly associated with an increase in noncalcified coronary plaque [β (SE) 2.0 (0.9); P = 0.025] and necrotic core plaque (1.7 (0.6); P = 0.009). In contrast, CIMT progression was not associated with the progression of coronary plaque, or coronary artery calcium (CAC) (P = NS).

CONCLUSION

Compared to CIMT, carotid plaque is a better indicator of coronary plaque progression. The appearance of a new carotid plaque is associated with significant progression of necrotic core and noncalcified plaque, which are high-risk coronary plaque components.

Macrophage accumulation within coronary arterial wall in diabetic patients with acute coronary syndrome: a study with in-vivo intravascular imaging modalities

Background and aims

Macrophage accumulation in arteriosclerotic plaque of coronary arteries is involved in plaque destabilization. Atherosclerosis has been known to be progressive in patients with type 2 diabetes mellitus (DM). This study compared the features of 3-dimensional (3D) spatial distribution of macrophage accumulation within coronary artery wall between acute coronary syndrome (ACS) patients with DM (n = 20) and those without (non-DM, n = 20) by using intravascular ultrasound (IVUS) and optical coherence tomography (OCT).

Methods

The OCT-derived macrophage accumulation was measured within the proximal left anterior-descending artery. This measurement was performed for the whole vessel segment of interest, higher shear stress region (flow divider side) and lower shear stress region (the opposite side).

Results

Normalized macrophage accumulation per unit length of the whole segment of interest was significantly larger in ACS patients with DM than without. In non-DM patients, macrophage density per IVUS-derived plaque volume was significantly higher in high shear stress region compared to low shear stress region, however, there was no significant difference between the two regions in DM patients. The macrophage density in the low shear stress region was significantly higher in the DM group than in the non-DM group. A multivariate analysis showed that the presence of DM was a major determinant for macrophage distribution.

Conclusions

Macrophage accumulation was more abundant and homogeneous within coronary arterial wall in DM patients with ACS compared to non-DM patients, suggesting that plaque destabilization may occur more widely throughout coronary wall in DM patients.

Coronary flow impairment in asymptomatic patients with early stage type-2 diabetes: Detection by FFRCT

PURPOSE

To determine the occurrence of physiological significant coronary artery disease (CAD) by coronary CT angiography (CTA) derived fractional flow reserve (FFRCT) in asymptomatic patients with a new diagnosis (<1 year) of type-2 diabetes mellitus (T2DM).

METHODS

FFRCT-analysis was performed from standard acquired coronary CTA data sets. The per-patient minimum distal FFRCT-value (d-FFRCT) in coronary vessels (diameter ⩾1.8 mm) was registered. The threshold for categorizing FFRCT-analysis as abnormal was a d-FFRCT ⩽0.75. Total plaque volume and volumes of calcified plaque, non-calcified plaque, and low-density non-calcified plaque (LD-NCP) were assessed by quantitative plaque analysis.

RESULTS

Overall, 76 patients; age, mean (SD): 56 (11) years; males, n (%): 49(65), were studied. A total of 57% of patients had plaques. The d-FFRCT was ⩽0.75 in 12 (16%) patients. The d-FFRCT, median (IQR), was 0.84 (0.79-0.87). Median (range) d-FFRCT in patients with d-FFRCT ⩽0.75 was 0.70 (0.6-0.74). Patients with d-FFRCT⩽0.75 versus d-FFRCT >0.75 had numerically higher plaque volumes for all plaques components, although only significant for the LD-NCP component.

CONCLUSION

Every sixth asymptomatic patient with a new diagnosis of T2DM has hemodynamic significant CAD as evaluated by FFRCT. Flow impairment by FFRCT was associated with coronary plaque characteristics.

Quantification of atherosclerotic plaque volume in coronary arteries by computed tomographic angiography in subjects with and without diabetes

Background

Diabetes mellitus (DM) is considered a cardiovascular risk factor. The aim of this study was to analyze the prevalence and volume of coronary artery plaque in patients with diabetes mellitus (DM) vs. those without DM.

Methods

This study recruited consecutive patients who underwent coronary computed tomography (CT) angiography (CCTA) between October 2016 and November 2017. Personal information including conventional cardiovascular risk factors was collected. Plaque phenotypes were automatically calculated for volume of different component. The volume of different plaque was compared between DM patients and those without DM.

Results

Among 6381 patients, 931 (14.59%) were diagnosed with DM. The prevalence of plaque in DM subjects was higher compared with nondiabetic group significantly (48.34% vs. 33.01%, χ² = 81.84, P < 0.001). DM was a significant risk factor for the prevalence of plaque in a multivariate model (odds ratio [OR] = 1.465, 95% CI: 1.258–1.706, P < 0.001). The volume of total plaque and any plaque subtypes in the DM subjects was greater than those in nondiabetic patients significantly (P < 0.001).

Conclusion

The coronary artery atherosclerotic plaques were significantly higher in diabetic patients than those in non-diabetic patients.

[Intravascular ultrasound with virtual histology in assessment of atherosclerotic plaque composition in patients with coronary artery disease and type 2 diabetes mellitus]

Type 2 diabetes mellitus (T2DM) is a serious medical and social problem leading to early disability of patients and high mortality from cardiovascular complications. The development of cardiovascular events is associated not only with the degree of coronary artery stenosis, but also with the structure of the atherosclerotic plaque.

AIM

This study aimed to characterize structure and composition of coronary artery atherosclerotic plaque in target lesion of T2DM patients and patients without diabetes using intravascular ultrasound (IVUS) and IVUS with virtual histology (IVUS-VH).

MATERIALS AND METHODS

We observed 25 patients with coronary artery disease (CAD) with T2DM and without T2DM, which admitted to Endocrinology Research Centre to perform percutaneous coronary intervention (PCI). Patients with CAD and T2DM were included at group 1 and patients with CAD and without T2DM were included at group 2. IVUS and IVUS-VH assessment of target lesion were performed prior to stent implantation. We observed 24 plaques at group 1 and 10 plaques at group 2.

RESULTS

In grey - scale IVUS 2D analysis there were no differences in mean cross - sectional area of the vessel (12.5 [10.4; 15.8] mm2 vs. 13.5 [12,7; 16.5] mm2; p=0.223, respectively) and lumen area (3.71 [2.5; 4.5] mm2 vs. 3.2 [2.7; 3.8] mm2; p=0.589, respectively). Plaque burden were higher in patients without T2DM (71.6 [65.5; 75.7] % vs. 77.6 [74.4; 80.4] %; p=0.008, respectively). IVUS-VH analysis showed that percent of necrotic core and dense calcium areas were significantly higher in the T2DM group (31.3 [25.3; 36.5] % vs. 21.65 [14.3; 27.8] %; p=0.01 and 4.7 [2.3; 7.8] % vs. 2.45 [1.2; 4.05] %; p=0.046, respectively). Percent of the fibrotic tissue were higher in non-T2DM group (55.35 [49.7; 63.6] % vs 67.7 [61.8; 76.5] %; p=0.004, respectively). There were no differences in percent of lipidic tissue in both groups.

CONCLUSIONS

IVUS-VH assessment of coronary artery atherosclerotic plaques showed greater amount of necrotic core and dense calcium in patients with T2DM compared to patients without diabetes.

Identification of Adipsin as a Novel Prognostic Biomarker in Patients With Coronary Artery Disease

Background

Circulating proteins are exposed to vascular endothelial layer and influence their functions. Among them, adipsin is a member of the trypsin family of peptidases and is mainly secreted from adipocytes, monocytes, and macrophages, catalyzing the rate‐limiting step of the alternative complement pathway. However, its pathophysiological role in cardiovascular disease remains to be elucidated. Here, we examined whether serum adipsin levels have a prognostic impact in patients with coronary artery disease.

Methods and Results

In 370 consecutive patients undergoing diagnostic coronary angiography, we performed a cytokine array analysis for screening serum levels of 50 cytokines/chemokines and growth factors. Among them, classification and regression analysis identified adipsin as the best biomarker for prediction of their long‐term prognosis (median 71 months; interquartile range, 55–81 months). Kaplan–Meier curve showed that higher adipsin levels (≥400 ng/mL) were significantly associated with all‐cause death (hazard ratio [HR], 4.2; 95% CI, 1.7–10.6 [P<0.001]) and rehospitalization (HR, 2.4; 95% CI, 1.7–3.5 [P<0.001]). Interestingly, higher high‐sensitivity C‐reactive protein levels (≥1 mg/L) were significantly correlated with all‐cause death (HR, 3.2; 95% CI, 1.7–5.9 [P<0.001]) and rehospitalization (HR, 1.5, 95% CI, 1.1–1.9 [P<0.01]). Importantly, the combination of adipsin (≥400 ng/mL) and high‐sensitivity C‐reactive protein (≥1 mg/L) was more significantly associated with all‐cause death (HR, 21.0; 95% CI, 2.9–154.1 [P<0.001]). Finally, the receiver operating characteristic curve demonstrated that serum adipsin levels predict the death caused by acute myocardial infarction in patients with coronary artery disease (C‐statistic, 0.847).

Conclusions

These results indicate that adipsin is a novel biomarker that predicts all‐cause death and rehospitalization in patients with coronary artery disease, demonstrating the novel aspects of the alternative complementary system in the pathogenesis of coronary artery disease.

Clinical significance of obstructive sleep apnea in patients with acute coronary syndrome in relation to diabetes status

OBJECTIVE

The prognostic significance of obstructive sleep apnea (OSA) in patients with acute coronary syndrome (ACS) according to diabetes mellitus (DM) status remains unclear. We aimed to elucidate the association of OSA with subsequent cardiovascular events in patients with ACS with or without DM.

RESEARCH DESIGN AND METHODS

In this prospective cohort study, consecutive eligible patients with ACS underwent cardiorespiratory polygraphy between June 2015 and May 2017. OSA was defined as an Apnea Hypopnea Index ≥15 events/hour. The primary end point was major adverse cardiovascular and cerebrovascular events (MACCEs), including cardiovascular death, myocardial infarction, stroke, ischemia-driven revascularization, or hospitalization for unstable angina or heart failure.

RESULTS

Among 804 patients, 248 (30.8%) had DM and 403 (50.1%) had OSA. OSA was associated with 2.5 times the risk of 1 year MACCE in patients with DM (22.3% vs 7.1% in the non-OSA group; adjusted HR (HR)=2.49, 95% CI 1.16 to 5.35, p=0.019), but not in patients without DM (8.5% vs 7.7% in the non-OSA group, adjusted HR=0.94, 95% CI 0.51 to 1.75, p=0.85). Patients with DM without OSA had a similar 1 year MACCE rate as patients without DM. The increased risk of events was predominately isolated to patients with OSA with baseline glucose or hemoglobin A1c levels above the median. Combined OSA and longer hypoxia duration (time with arterial oxygen saturation <90%>22 min) further increased the MACCE rate to 31.0% in patients with DM.

CONCLUSIONS

OSA was associated with increased risk of 1 year MACCE following ACS in patients with DM, but not in non-DM patients. Further trials exploring the efficacy of OSA treatment in high-risk patients with ACS and DM are warranted.

Natural History of Diabetic Coronary Atherosclerosis by Quantitative Measurement of Serial Coronary Computed Tomographic Angiography: Results of the PARADIGM Study

OBJECTIVES

This study aimed to determine the rate and extent of plaque progression (PP), changes in plaque features, and clinical predictors of PP in patients with diabetes mellitus (DM).

BACKGROUND

The natural history of coronary PP in patients with DM is not well established.

METHODS

A total of 1,602 patients (age 61.3 ± 9.0 years; 60.3% men; median scan interval 3.8 years) who underwent serial coronary computed tomography angiography over a period of at least 24 months were enrolled and analyzed from the PARADIGM (Progression of Atherosclerotic Plaque Determined by Computed Tomographic Angiography Imaging) trial. Study endpoints were changes in plaque features in diabetics with PP and risk factors for PP by serial coronary computed tomography angiography between patients with and without DM. PP was defined if plaque volume at follow-up minus plaque volume at baseline was >0.

RESULTS

DM was an independent risk factor for PP (84.6%; 276 of 326 patients with PP) in multivariate analysis (odds ratio [OR]: 1.526; 95% confidence interval [CI]: 1.100 to 2.118; p = 0.011). Independent risk factors for PP in patients with DM were male sex (OR: 1.485; 95% CI: 1.003 to 2.199; p = 0.048) and mean plaque burden at baseline ≥75% (OR: 3.121; 95% CI: 1.701 to 5.725; p ≤0.001). After propensity matching, percent changes in overall plaque volume (30.3 ± 36.9% in patients without DM and 36.0 ± 29.7% in those with DM; p = 0.032) and necrotic core volume (-7.0 ± 35.8% in patients without DM and 21.5 ± 90.5% in those with DM; p = 0.007) were significantly greater in those with DM. The frequency of spotty calcification, positive remodeling, and burden of low-attenuation plaque were significantly greater in patients with DM.

CONCLUSIONS

People with DM experience greater PP, particularly significantly greater progression in adverse plaque, than those without DM. Male sex and mean plaque burden >75% at baseline were identified as independent risk factors for PP.

Plaque volume and plaque risk profile in diabetic vs. non-diabetic patients undergoing lipid-lowering therapy: a study based on 3D intravascular ultrasound and virtual histology

Background

Coronary atherosclerosis progresses faster in patients with diabetes mellitus (DM) and causes higher morbidity and mortality in such patients compared to non-diabetics ones (non-DM). We quantify changes in plaque volume and plaque phenotype during lipid-lowering therapy in DM versus non-DM patients using advanced intracoronary imaging.

Methods

We analyzed data from 61 patients with stable angina pectoris included to the PREDICT trial searching for prediction of plaque changes during intensive lipid-lowering therapy (40 mg rosuvastatin daily). Geometrically correct, fully 3-D representation of the vascular wall surfaces and intravascular ultrasound virtual histology (IVUS-VH) defined tissue characterization was obtained via fusion of two-plane angiography and IVUS-VH. Frame-based indices of plaque morphology and virtual histology analyses were computed and averaged in 5 mm long baseline/follow-up registered vessel segments covering the entire length of the two sequential pullbacks (baseline, 1-year). We analyzed 698 5-mm-long segments and calculated the Liverpool active plaque score (LAPS).

Results

Despite reaching similar levels of LDL cholesterol (DM 2.12 ± 0.91 mmol/l, non-DM 1.8 ± 0.66 mmol/l, p = 0.21), DM patients experienced, compared to non-DM ones, higher progression of mean plaque area (0.47 ± 1.15 mm² vs. 0.21 ± 0.97, p = 0.001), percent atheroma volume (0.7 ± 2.8% vs. − 1.4 ± 2.5%, p = 0.007), increase of LAPS (0.23 ± 1.66 vs. 0.13 ± 1.79, p = 0.018), and exhibited more locations with TCFA (Thin-Cap Fibro-Atheroma) plaque phenotype in 5 mm vessel segments (20.3% vs. 12.5%, p = 0.01). However, only non-DM patients reached significant decrease of LDL cholesterol. Plaque changes were more pronounced in PIT (pathologic intimal thickening) compared to TCFA with increased plaque area in both phenotypes in DM patients.

Conclusion

Based on detailed 3D analysis, we found advanced plaque phenotype and further atherosclerosis progression in DM patients despite the same reached levels of LDLc as in non-DM patients.

Trial registration ClinicalTrials.gov identifier: NCT01773512

Type 2 diabetes mellitus is associated with a lower fibrous cap thickness but has no impact on calcification morphology: an intracoronary optical coherence tomography study

Background

Patients with type 2 diabetes (T2DM) are at high risk for cardiovascular events, which usually arise from the rupture of a vulnerable coronary plaque. The minimal fibrous cap thickness (FCT) overlying a necrotic lipid core is an established predictor for plaque rupture. Recently, coronary calcification has emerged as a relevant feature of plaque vulnerability. However, the impact of T2DM on these morphological plaque parameters is largely unexplored. Therefore, this study aimed to compare differences of coronary plaque morphology in patients with and without T2DM with a particular focus on coronary calcification.

Methods

In 91 patients (T2DM = 56, non-T2DM = 35) with 105 coronary de novo lesions (T2DM = 56, non-T2DM = 49) plaque morphology and calcification were analyzed using optical coherence tomography (OCT) prior to coronary intervention.

Results

Patients with T2DM had a lower minimal FCT (80.4 ± 27.0 µm vs. 106.8 ± 27.8 µm, p < 0.001) and a higher percent area stenosis (77.9 ± 8.1% vs. 71.7 ± 11.2%, p = 0.001) compared to non-diabetic subjects. However, patients with and without T2DM had a similar total number of calcifications (4.0 ± 2.6 vs. 4.2 ± 3.1, p = ns) and no significant difference was detected in the number of micro- (0.34 ± 0.79 vs. 0.31 ± 0.71), spotty (2.11 ± 1.77 vs. 2.37 ± 1.89) or macro-calcifications (1.55 ± 1.13 vs. 1.53 ± 0.71, all p = ns). The mean calcium arc (82.3 ± 44.8° vs. 73.7 ± 31.6), the mean thickness of calcification (0.54 ± 0.13 mm vs. 0.51 ± 0.15 mm), the mean calcified area (0.99 ± 0.72 mm² vs. 0.78 ± 0.49 mm²), the mean depth of calcification (172 ± 192 μm vs. 160 ± 76 μm) and the cap thickness overlying the calcification (50 ± 71 μm vs. 62 ± 61 μm) did not differ between the diabetic and non-diabetic groups (all p = ns).

Conclusion

T2DM has an impact on the minimal FCT of the coronary target lesion, but not on localization, size, shape or extent of calcification. Thus, the minimal FCT overlying the necrotic lipid core but not calcification is likely to contribute to the increased plaque vulnerability observed in patients with T2DM.

Impact of renal function on the underlying pathophysiology of coronary plaque composition in patients with type 2 diabetes mellitus

BACKGROUND

Both the progression of diabetic kidney disease and increased glycemic variability play important roles in the pathogenesis of coronary plaque formation via inflammatory pathways in patients with type 2 diabetes mellitus (T2DM). Therefore we evaluated the role of renal function in the contributory effects of blood glucose fluctuations and blood levels of inflammatory cytokine concentrations on the tissue characteristics of coronary plaques in patients with T2DM.

METHODS

We prospectively enrolled 71 T2DM patients (mean age: 68 ± 9, male 79%) with 153 coronary artery lesions. Patients were divided into 2 groups according to their estimated glomerular filtration rate (eGFR) levels: Group 1 (≥ 60 mL/min/1.73 m², n = 40) and Group 2 (< 60 mL/min/1.73 m², n = 31). All patients underwent continuous glucose monitoring (CGM) for 120 h and the mean amplitude of glycemic excursions (MAGE) was calculated. Serum tumor necrosis factor (TNF)-α was also measured. In addition, gray-scale coronary intravascular ultrasound (IVUS) and iMap-IVUS were performed in the coronary lesions with < 50% luminal reduction.

RESULTS

In Group 1, MAGE correlated with percent lipidic volume (%LV) (r = 0.477, p = 0.002). In this group, stepwise multivariate linear regression analyses showed that only MAGE was independently associated with %LV (β = 0.477, p = 0.002). In contrast, in Group 2, only serum TNF-α correlated with percent fibrotic volume (%FV) (r = - 0.471, p = 0.007), %LV (r = 0.496, p = 0.005) and percent necrotic volume (%NV) (r = 0.426, p = 0.017). In this group, stepwise multivariate linear regression analyses showed that only serum TNF-α was independently associated with each tissue characteristic (%FV β = - 0.471 and p = 0.007, %LV β = 0.496 and p = 0.005, %NV: β = 0.426 and p = 0.017).

CONCLUSIONS

In T2DM patients, the tissue characteristics of coronary plaques were associated with MAGE in patients with eGFR ≥ 60 mL/min/1.73 m² and with serum TNF-α in those with eGFR < 60 mL/min/1.73 m².

PRotective Effect on the coronary microcirculation of patients with DIabetes by Clopidogrel or Ticagrelor (PREDICT): study rationale and design. A randomized multicenter clinical trial using intracoronary multimodal physiology

Background

In diabetic patients a predisposed coronary microcirculation along with a higher risk of distal particulate embolization during primary percutaneous intervention (PCI) increases the risk of peri-procedural microcirculatory damage. However, new antiplatelet agents, in particular Ticagrelor, may protect the microcirculation through its adenosine-mediated vasodilatory effects.

Methods

PREDICT is an original, prospective, randomized, multicenter controlled study designed to investigate the protective effect of Ticagrelor on the microcirculation during PCI in patient with diabetes mellitus type 2 or pre-diabetic status. The primary endpoints of this study aim to test (i) the decrease in microcirculatory resistance with antiplatelet therapy (Ticagrelor > Clopidogrel; mechanistic effect) and (ii) the relative microcirculatory protection of Ticagrelor compared to Clopidogrel during PCI (Ticagrelor < Clopidogrel; protective effect).

Conclusions

PREDICT will be the first multicentre clinical trial to test the adenosine-mediated vasodilatory effect of Ticagrelor on the microcirculation during PCI in diabetic patients. The results will provide important insights into the prospective beneficial effect of this drug in preventing microvascular impairment related to PCI (http://www.clinicaltrials.gov No. NCT02698618).

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0543-5) contains supplementary material, which is available to authorized users.

Statin-induced improvements in vulnerable plaques are attenuated in poorly controlled diabetic patients with coronary atherosclerosis disease: a serial optical coherence tomography analysis

AIMS

The incidence of cardiac events is increased in diabetic patients even after lipid-lowering therapy. This study aimed to compare the statin-induced changes in the characteristics of vulnerable plaques in patients without diabetes mellitus (DM) and in those with better- or poorly controlled DM, measured by optical coherence tomography (OCT).

METHODS

This was a retrospective study of 99 non-culprit lipid-rich plaques from 75 patients who underwent intensive OCT imaging examination. Thirty-four non-diabetic patients were assigned to Group A. According to the average HbA1c level, 22 diabetic patients were assigned to Group B, and 19, to Group C (average HbA1c < 8 and ≥8 %, respectively).

RESULTS

Following 12 months of statin therapy, similar improvements in serum lipid levels were observed in the three groups. However, the increase in fibrous-cap thickness of plaques was the highest in Group A (Group A, 183 %; Group B, 104 %; and Group C, 53 %). Significant reductions in lipid volume index were observed in Groups A and B (Group A: -12 %, P < 0.001; Group B: -13 %, P = 0.038; Group C: 7 %, P = 0.948). Percent changes in OCT measurements were significantly correlated with average HbA1c in patients.

CONCLUSIONS

Improved glucose control may enhance the statin-induced reduction in characteristics of vulnerable plaque in diabetic patients.

Combined optical coherence tomography morphologic and fractional flow reserve hemodynamic assessment of non- culprit lesions to better predict adverse event outcomes in diabetes mellitus patients: COMBINE (OCT-FFR) prospective study. Rationale and design

BACKGROUND

Fractional flow reserve (FFR) is a widely used tool for the identification of ischaemia-generating stenoses and to guide decisions on coronary revascularisation. However, the safety of FFR-based decisions in high-risk subsets, such as patients with Diabetes Mellitus (DM) or vulnerable stenoses presenting thin-cap fibro-atheroma (TCFA), is unknown. This study will examine the impact of optical coherence tomography (OCT) plaque morphological assessment and the identification of TCFA, in combination with FFR to better predict clinical outcomes in DM patients.

METHODS

COMBINE (OCT-FFR) is a prospective, multi-centre study investigating the natural history of DM patients with ≥1 angiographically intermediate target lesion in three subgroups of patients; patients with FFR negative lesions without TCFA (group A) and patients with FFR negative lesions with TCFA (group B) as detected by OCT and to compare these two groups with each other, as well as to a third group with FFR-positive, PCI-treated intermediate lesions (group C). The study hypothesis is that DM patients with TCFA (group B) have a worse outcome than those without TCFA (group A) and also when compared to those patients with lesions FFR ≤0.80 who underwent complete revascularisation. The primary endpoint is the incidence of target lesion major adverse cardiac events (MACE); a composite of cardiac death, myocardial infarction or rehospitalisation for unstable/progressive angina in group B vs. group A.

CONCLUSION

COMBINE (OCT-FFR) is the first prospective study to examine whether the addition of OCT plaque morphological evaluation to FFR haemodynamic assessment of intermediate lesions in DM patients will better predict MACE and possibly lead to new revascularisation strategies. Trial Registration Netherlands Trial Register: NTR5376.

[Diabetes and type of diet as determinant factor in the progression of atherosclerosis]

The purpose of this review is to analyze the biochemical progression of atherosclerotic plaque and its association with diet and diabetes. This study shows the scientific evidence of demonstrating that diabetic patients present high levels of fatty acids like palmitic acid and linoleic acid in their atheroma plaques in comparison with non-diabetic patients. This study also establishes how patients with diabetes mellitus have a higher prevalence of atherosclerotic heart diseases in the form of Coronary Thrombosis and have different anatomopathological appearance like higher necrotic core and thin fibrotic layer than the general population. Furthermore this review describes the different anatomopathological appearance and cellular changes involved in the formation of these plaques and how diet can affect the development of these plaques.

Feasibility of diagnosing unstable plaque in patients with acute coronary syndrome using iMap-IVUS

OBJECTIVE

To compare the plaque composition between stable and unstable plaques, characterize unstable plaque by using iMap-intravascular ultrasound (IVUS), and quantify the diagnostic criteria for unstable plaque.

METHODS

Thirty-three acute coronary syndrome (ACS) patients who had undergone coronary angiography and IVUS from February 19, 2014 to December 19, 2014 at Peking University People's Hospital were enrolled in the study. Baseline data were collected. The patients were divided into two groups according to their gray-scale IVUS imaging, stable plaque and unstable plaque. A difference-in-difference evaluation was performed using the baseline data and off-line iMap imaging results between the two groups. A receiver operating characteristic (ROC) curve was constructed to obtain the optimal cut-off value to diagnose unstable plaque.

RESULTS

Percentages of fibrotic and necrotic tissues, absolute values of lipidic, necrotic, and calcified tissues, and plaque burden were independent predictors for unstable plaque. Absolute necrotic area was the best predictor and exhibited the highest diagnostic value for plaque vulnerability (area under the curve (AUC)=0.806, P=0.000, 95% CI (0.718, 0.894)). The cut-off score for predicting unstable plaque was 4.0 mm(2).

CONCLUSIONS

This study attempted to propose a cut-off value based on absolute necrotic area using iMap-IVUS to predict plaque vulnerability in patients with ACS. This score might provide a valuable reference for diagnosing unstable plaque.

Imaging of coronary atherosclerosis in various susceptible groups

Coronary artery disease (CAD) is the leading cause of death and disability worldwide. Atherosclerosis, which is the primary pathophysiologic mechanism for the development of plaque leading to CAD, is a multifactorial process resulting from a complex interplay between genetic susceptibility and various risk factors such as hypertension (HT), dyslipidaemia, diabetes mellitus (DM) and smoking. In addition, influences from other disease states such as chronic kidney disease (CKD), obesity and the metabolic syndrome as well as gender and ethnic diversity also contribute to the disease process. Insights from pathological observations and advances in cellular and molecular biology have helped us understand the process of plaque formation, progression and rupture leading to events. Several intravascular imaging techniques such as intravascular ultrasound (IVUS), Virtual histology IVUS (VH-IVUS) and optical coherence tomography (OCT) allow in vivo assessment of plaque burden, plaque morphology and response to therapy. In addition, non invasive assessment using coronary artery calcium (CAC) score allows risk stratification and plaque burden assessment whilst computed tomography coronary angiography (CTCA) allows evaluation of luminal stenosis, plaque characterisation and quantification. This review aims to summarise the results of invasive and non-invasive imaging studies of coronary atherosclerosis seen in various high-risk populations including DM, metabolic syndrome, obesity, CKD and, gender differences and ethnicity. Understanding the phenotype of plaques in various susceptible groups may allow potential development of personalised therapies.

Impact of TCFA on Unanticipated Ischemic Events in Medically Treated Diabetes Mellitus: Insights From the PROSPECT Study

OBJECTIVES

This study sought to investigate the relationship between thin-cap fibroatheromas (TCFAs) on major adverse cardiac events (MACEs) arising from medically treated nonculprit lesions (NCLs) in patients with acute coronary syndromes (ACS) with and without diabetes mellitus (DM).

BACKGROUND

MACEs occur frequently in patients with DM and ACS. The impact of plaque composition on subsequent MACEs in DM patients with ACS is unknown.

METHODS

In the PROSPECT (Providing Regional Observations Study Predictors of Events in the Coronary Tree) study, using 3-vessel radiofrequency intravascular ultrasound, we analyzed the incidence of NCL-MACE in 2 propensity-matched groups according to the presence of DM and TCFA.

RESULTS

Among 697 patients, 119 (17.7%) had DM. The 3-year total MACE rate (29.4% vs. 18.8%; p = 0.01) was significantly higher in patients with versus without DM, driven by a higher rate of NCL-MACE in DM (18.7% vs. 10.4%; p = 0.02). Propensity score matching generated 2 balanced groups with and without DM of 82 patients each. Among DM patients, the presence of ≥1 TCFA was associated with higher NCL-MACE at 3 years (27.8% vs. 8.9% in patients without a TCFA, hazard ratio: 3.56; 95% confidence interval: 0.98 to 12.96; p = 0.04). DM patients without a TCFA had a similar 3-year rate of NCL-MACE as patients without DM (8.9% vs. 8.9%; hazard ratio: 1.09; 95% confidence interval: 0.27 to 4.41; p = 0.90).

CONCLUSIONS

ACS patients with DM and ≥1 TCFA have a high rate of NCL-MACE at 3 years. In contrast, the prognosis of ACS patients with DM but no TCFAs is favorable and similar to patients without DM.

Relation between fractional flow reserve value of coronary lesions with deferred revascularization and cardiovascular outcomes in non-diabetic and diabetic patients

BACKGROUND

FFR of deferred PCI lesions can predict future cardiovascular events. However, the prognostic utility of FFR remains unclear in diabetic patients in view of the potential impact of the diffuse nature of vascular disease process. We aimed to study the relation between fractional flow reserve (FFR) values and long-term outcomes of diabetic and non-diabetic patients with deferred percutaneous coronary intervention (PCI).

METHODS

Patients with FFR assessment and deferred PCI (n=630) were enrolled and stratified according to diabetes mellitus (DM) status and FFR values. Patients were followed over a median of 39months. Cox proportional hazard regression models were used to analyze the association between clinical endpoints and clinical factors such as DM and FFR.

RESULTS

In non-diabetics (n=450), higher FFR values were associated with less cardiovascular events (hazard ratio (HR) for death and myocardial infarction (MI) [95% confidence interval (CI)], 0.61[0.44 to 0.86] per 0.1 increase in FFR, p=0.007; HR for revascularization [95%CI], 0.66[0.49 to 0.9] per 0.1 increase in FFR, p=0.006). In diabetics (n=180), there was no difference in death and MI across the range of FFR values. Among those patients with an FFR >0.85, diabetics had a more than two-fold higher risk of death and MI than non-diabetics (HR [95% CI], 2.20 [1.19 to 4.01], p=0.015).

CONCLUSION

Among non-diabetic patients with deferred PCI, a higher FFR was associated with lower rates of death, MI and revascularization. On the contrary in diabetic patients with deferred revascularization, FFR was not able to differentiate the risk of cardiovascular events.

Coronary atherosclerosis is already ongoing in pre-diabetic status: Insight from intravascular imaging modalities

Diabetes mellitus is a powerful risk factor of coronary artery disease (CAD), leading to death and disability. In recent years, given the accumulating evidence that prediabetes is also related to increasing risk of CAD including cardiovascular events, a new guideline has been proposed for the treatment of blood cholesterol for primary prevention of cardiovascular events. This guideline recommends aggressive lipid-lowering statin therapy for primary prevention in diabetes and other patients. The ultimate goal of patient management is to inhibit progression of systemic atherosclerosis and prevent fatal cardiovascular events such as acute coronary syndrome (ACS). Because disruption of atherosclerotic coronary plaques is a trigger of ACS, the high-risk atheroma is called a vulnerable plaque. Several types of novel diagnostic imaging technologies have been developed for identifying the characteristics of coronary atherosclerosis before the onset of ACS, especially vulnerable plaques. According to coronary angioscopic evaluation, atherosclerosis severity and plaque vulnerability were more advanced in prediabetic than in nondiabetic patients and comparable to that in diabetic patients. In addition, pharmacological intervention by statin therapy changed plaque color and complexity, and the dynamic changes in plaque features are considered plaque stabilization. In this article, we review the findings of atherosclerosis in prediabetes, detected by intravascular imaging modalities, and the therapeutic implications.

Coronary artery plaque volume and obesity in patients with diabetes: the factor-64 study

PURPOSE

To determine the relationship between coronary plaque detected with coronary computed tomographic (CT) angiography and clinical parameters and cardiovascular risk factors in asymptomatic patients with diabetes.

MATERIALS AND METHODS

All patients signed institutional review board-approved informed consent forms before enrollment. Two hundred twenty-four asymptomatic diabetic patients (121 men; mean patient age, 61.8 years; mean duration of diabetes, 10.4 years) underwent coronary CT angiography. Total coronary artery wall volume in all three vessels was measured by using semiautomated software. The coronary plaque volume index (PVI) was determined by dividing the wall volume by the coronary length. The relationship between the PVI and cardiovascular risk factors was determined with multivariable analysis.

RESULTS

The mean PVI (±standard deviation) was 11.2 mm(2) ± 2.7. The mean coronary artery calcium (CAC) score (determined with the Agatston method) was 382; 67% of total plaque was noncalcified. The PVI was related to age (standardized β = 0.32, P < .001), male sex (standardized β = 0.36, P < .001), body mass index (BMI) (standardized β = 0.26, P < .001), and duration of diabetes (standardized β = 0.14, P = .03). A greater percentage of soft plaque was present in younger individuals with a shorter disease duration (P = .02). The soft plaque percentage was directly related to BMI (P = .002). Patients with discrepancies between CAC score and PVI rank quartiles had a higher percentage of soft and fibrous plaque (18.7% ± 3.3 vs 17.4% ± 3.5 [P = .008] and 52.2% ± 7.2 vs 47.2% ± 8.8 [P < .0001], respectively).

CONCLUSION

In asymptomatic diabetic patients, BMI was the primary modifiable risk factor that was associated with total and soft coronary plaque as assessed with coronary CT angiography.

Low high-density lipoprotein cholesterol is a residual risk factor associated with long-term clinical outcomes in diabetic patients with stable coronary artery disease who achieve optimal control of low-density lipoprotein cholesterol

Diabetes mellitus is recognized an independent risk factor for coronary artery disease (CAD) and mortality. Clinical trials have shown that statins significantly reduce cardiovascular events in diabetic patients. However, residual cardiovascular risk persists despite the achievement of target low-density lipoprotein cholesterol (LDL-C) levels with statin. High-density lipoprotein cholesterol (HDL-C) is an established coronary risk factor that is independent of LDL-C levels. We evaluated the impact of HDL-C on long-term mortality in diabetic patients with stable CAD who achieved optimal LDL-C. We enrolled 438 consecutive diabetic patients who were scheduled for percutaneous coronary intervention between 2004 and 2007 at our institution. We identified 165 patients who achieved target LDL-C <100 mg/dl. Patients were stratified into two groups according to HDL-C levels (low HDL-C group, baseline HDL-C <40 mg/dl; high HDL-C group, ≥40 mg/dl). Major adverse cardiac events (MACE) that included all-cause death, acute coronary syndrome, and target lesion revascularization were evaluated between the two groups. The median follow-up period was 946 days. The rate of MACE was significantly higher in diabetic patients with low-HDL-C who achieved optimal LDL-C (6.9 vs 17.9 %, log-rank P = 0.030). Multivariate Cox regression analysis showed that HDL-C is significantly associated with clinical outcomes (adjusted hazard ratio for MACE 1.33, 95 % confidence interval 1.01-1.75, P = 0.042). Low HDL-C is a residual risk factor that is significantly associated with long-term clinical outcomes among diabetic patients with stable CAD who achieve optimal LDL-C levels.

The association of diabetes mellitus with clinical outcomes after coronary stenting: a meta-analysis

Background

Previous studies have shown inconsistent results on the association between diabetes mellitus (DM) and some clinical outcomes. We conducted a meta-analysis of observational studies to assess effect of DM on clinical outcomes after coronary stenting.

Methods

We searched for studies without language restriction in PubMed, Embase and Cochrane library prior to 2012. The clinical outcomes including in-stent restenosis (ISR), major adverse cardiac events (MACE), stent thrombosis (ST), target lesion revascularization (TLR) and target vessel revascularization (TVR). Adjusted odds ratio (OR), and the corresponding 95% confidence interval (95% CI) was summarized.

Results

55 studies involving 128,084 total patients (38,416 DM patients and 89,668 controls) were eligible for our analysis. Overall, there were significant associations between DM and ISR (OR = 1.70, 95% CI: 1.53–1.89, I² = 0.0%), MACE (OR = 1.54, 95% CI: 1.36–1.73, I² = 29.0%), ST (OR = 2.01, 95% CI: 1.36–2.97, I² = 47.7%), TLR (OR = 1.46, 95% CI: 1.26–1.68, I² = 43.3%) as well as TVR (OR = 1.33, 95% CI: 1.17–1.51, I² = 48.3). Subgroup analysis showed that the associations were similar between BMS and DES implantation. Moreover, there was no significant association in the ST subgroup after 1–3 years follow-up.

Conclusions

Our meta-analysis suggests that after coronary stent implantation, DM is associated with ISR, MACE, ST, TLR and TVR. DM appears to be a vital risk factor of these clinical outcomes.

Insulin resistance is associated with coronary plaque vulnerability: insight from optical coherence tomography analysis

AIMS

Previous studies have reported that insulin resistance plays an important role in the progression of atherosclerosis. However, the relationship between insulin resistance and coronary plaque instability is not well established. The purpose of this study was to assess the relationship between insulin resistance and coronary plaque characteristics identified by optical coherence tomography (OCT).

METHODS AND RESULTS

This study enrolled 155 consecutive patients undergoing percutaneous coronary intervention. OCT image acquisitions were performed in the culprit lesions. Insulin resistance was identified using the homeostasis model assessment of insulin resistance (HOMA-IR). Subjects were divided into three tertiles according to the HOMA-IR values. Patients in the higher HOMA tertile had more frequent prevalence of lipid-rich plaques than those in the middle and lower tertiles (83 vs. 62 vs. 57%; P = 0.01). The thin-cap fibroatheroma (TCFA) prevalence rates among the higher (>2.5), middle (1.4-2.5), and lower HOMA-IR (<1.4) tertiles were 50, 29, and 26% (P = 0.02). The microvessel prevalence rates of the three tertiles were 54, 39, and 28% (P = 0.02). Furthermore, in the higher HOMA-IR group, the fibrous cap was significantly thinner compared with the other two tertiles (vs. lower HOMA-IR, P = 0.009; vs. middle HOMA-IR, P = 0.008). On multivariate analysis, acute coronary syndrome [odds ratio (OR): 17.98; 95% confidence interval (CI): 7.12-52.02; P < 0.0001] and HOMA-IR >2.50 (OR: 3.57; 95% CI: 1.42-9.55; P = 0.007) were independent predictors for the presence of TCFA.

CONCLUSION

This study suggests that insulin resistance might be associated with coronary plaque vulnerability.

Evolution of intravascular assessment of coronary anatomy and physiology: from ultrasound imaging to optical and flow assessment

The fact that coronary angiography has limitations in terms of precise estimation and progression of atherosclerosis has been partially overcome during the last years by the use of new techniques. Catheter-based invasive modalities are of a profound clinical importance in regard to accurate assessment of coronary anatomy and physiology and the choice of the appropriate treatment strategy for each patient. Also their potential in clinical investigation projects is of great interest. This current review summarizes the basic principles of these methodologies and evidently highlights not only their use in clinical practice but also their contribution in clinical outcomes.

Comparison of nonculprit coronary plaque characteristics between patients with and without diabetes: a 3-vessel optical coherence tomography study

OBJECTIVES

The aim of the present study was to compare the characteristics of nonculprit coronary plaques between diabetes mellitus (DM) and non-DM patients using 3-vessel optical coherence tomography (OCT) imaging.

BACKGROUND

DM patients have a higher recurrent cardiovascular event rate.

METHODS

Patients who had undergone 3-vessel OCT imaging were identified from the Massachusetts General Hospital OCT Registry. Characteristics of nonculprit plaques were compared between DM and non-DM patients.

RESULTS

A total of 230 nonculprit plaques were identified in 98 patients. Compared with non-DM patients, DM patients had a larger lipid index (LI) (averaged lipid arc × lipid length; 778.6 ± 596.1 vs. 1358.3 ± 939.2, p < 0.001) and higher prevalence of calcification (48.4% vs. 72.2%, p = 0.034) and thrombus (0% vs. 8.3%, p = 0.047). DM patients were divided into 2 groups based on glycated hemoglobin (A(1C)) levels of ≤7.9% and ≥8.0%. LI was significantly correlated with diabetic status (778.6 ± 596.1 [non-DM] vs. 1,171.5 ± 708.1 [A(1C) ≤7.9%] vs. 1,638.5 ± 1,173.8 [A(1C) ≥8%], p value for linear trend = 0.005), and fibrous cap thickness was inversely correlated with the A(1C) level (99.4 ± 46.7 μm [non-DM] vs. 91.7 ± 29.6 μm [A(1C) ≤7.9%] vs. 72.9 ± 22.7 μm [A(1C) ≥8%], p value for linear trend = 0.014). Patients with A(1C) ≥8% also had the highest prevalence of thin-cap fibroatheroma (TCFA) and macrophage infiltration.

CONCLUSIONS

Compared with non-DM patients, DM patients have a larger LI and a higher prevalence of calcification and thrombus. The LI was larger and TCFA and macrophage infiltration were frequent in patients with A(1C) ≥8%.