Non-culprit plaque characteristics in acute coronary syndrome patients with raised hemoglobinA1c: an intravascular optical coherence tomography study

Coronary artery calcification and plaque stability： an optical coherence tomography study

Background

Coronary artery calcification (CAC), a surrogate of atherosclerosis, is related to stent underexpansion and adverse cardiac events. However, the effect of CAC on plaque stability is still controversial and the morphological significance of CAC has yet to be elucidated.

Methods

A retrospective series of 419 patients with acute coronary syndrome (ACS) who underwent optical coherence tomography (OCT) were enrolled. Patients were classified into three groups based on the calcification size in culprit plaques and the features of the culprit and non-culprit plaques among these groups were compared. Logistic regression was used to analyze independent risk factors for culprit plaque rupture and the nonlinear relationship between calcification parameters and culprit plaque rupture. Furthermore, we compared the detailed calcification parameters of different kinds of plaques.

Results

A total of 419 culprit plaques and 364 non-culprit plaques were identified. The incidence of calcification was 53.9 % in culprit plaques and 50.3 % in non-culprit plaques. Compared with culprit plaques without calcification, plaque rupture, macrophages and cholesterol crystals were more frequently observed in the spotty calcification group, and the lipid length was longer; the incidence of macrophages and cholesterol crystals was higher in the macrocalcification group. Calcification tended to be smaller in ruptured plaques than in non-ruptured plaques. Moreover, the arc and length of calcification were greater in culprit plaques than in non-culprit plaques.

Conclusions

Vulnerable features were more frequently observed in culprit plaques with spotty calcification, whereas the presence of macrocalcification calcifications did not significantly increase plaque vulnerability. Calcification tends to be larger in culprit plaques than in non-culprit plaques.

Association of pre-diabetes and type 2 diabetes mellitus with intracranial plaque characteristics in patients with acute ischemic stroke

OBJECTIVES

To investigate the association of pre-diabetes(i.e., the early stages of glucometabolic disturbance) and Type 2 diabetes mellitus (T2DM) with intracranial plaque characteristics in patients with acute ischemic stroke using three-dimensional high-resolution MR imaging.

METHODS

One hundred and forty-three symptomatic patients with acute ischemic stroke attribute to intracranial atherosclerotic plaque were prospectively enrolled. All participants were further divided into three groups: normal glucose metabolism(non-diabetes) group(n = 41), pre-diabetes group(n = 45), and T2DM group(n = 57) according to glucometabolic status. Culprit plaque characteristics (such as plaque burden, normalized wall index and enhancement ratio), total plaque number, and global plaque enhancement score were analyzed and compared among the three glucometabolic groups. The association between pre-diabetes and T2DM with intracranial plaque characteristics was assessed by logistic regression and multivariate linear regression.

RESULTS

Plaque number was higher in patients with pre-diabetes and T2DM compared with those with non-diabetes(3.71 ± 1.83 and 3.75 ± 1.71 vs 2.24 ± 1.46, p = 0.006). Multivariate logistic regression showed a significant association of multiple intracranial plaques with pre-diabetes(OR 3.524, 95% CI 1.082 ~ 11.479, p = 0.037), T2DM(OR 3.760, 95% CI 1.098 ~ 12.872, p = 0.035) and luminal stenotic rate. Both pre-diabetes and T2DM were significantly associated with culprit plaque enhancement ratio(β = 0.527 and β = 0.536; respectively; p < 0.001) and global plaque enhancement score(β = 0.264 and β = 0.373; respectively; p < 0.05).

CONCLUSIONS

Patients with pre-diabetes and T2DM had similar intracranial atherosclerotic plaque vulnerability, as demonstrated by multiple plaques, increased culprit plaque enhancement ratio and global plaque enhancement score.

ADVANCES IN KNOWLEDGE

Pre-diabetes might be a risk factor for intracranial plaque vulnerability. It is necessary to monitor a slight increase in blood glucose in non-diabetes patients with acute ischemic stroke.

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 relationship between Hemoglobin A1c and the maximal plaque stress of culprit ruptured plaques in patients with ST-segment elevated myocardial infarction

BACKGROUND

Plaque rupture occurs when the structural stress inside plaques exceeds the capacity of the overlying fibrous cap. Plaque structural stress has been acknowledged as an index to evaluate the risk of plaque rupture. However, impacting factors associated with the level of plaque structural stress in ST-segment elevated myocardial infarction patients with ruptured plaques remain unknown.

METHODS

Based on optical coherence tomography, we analyzed the plaque characteristics and calculated the maximal plaque stress of the culprit lesions in 162 patients with plaque rupture by performing finite element analysis. All enrolled patients were divided into two groups according to the level of maximal plaque stress. Cardiovascular risk factors, laboratory findings and clinical outcomes were compared between the two groups.

RESULTS

Hemoglobin A1c (HbA1c) was significantly higher in the high stress group than in the low stress group (7.0% ± 1.8 vs. 6.3% ± 1.2, p = 0.003). The maximal plaque stress of patients with diabetes was significantly higher than that of patients without diabetes (538.7 kPa [346.2-810.6] vs. 425.9 kPa [306.2-571.4], p = 0.006). Moreover, the level of maximal plaque stress was significantly associated with HbA1c (Pearson's correlation coefficient: r = 0.289, P < 0.001). OCT findings showed that the fibrous cap thickness and maximal lipid arc were significantly associated with maximal plaque stress (r = -0.163, p = 0.038; r = 0.194, p = 0.013, respectively).

CONCLUSION

OCT-based finite-element analysis showed that HbA1c was independently associated with the level of maximal plaque stress in STEMI patients with plaque rupture, thus indicating the importance of glucose control in patients with coronary atherosclerotic disease.

Impact of prediabetes and duration of diabetes on radial artery atherosclerosis in acute coronary syndrome patients: An optical coherence tomography study

BACKGROUND

Prediabetes (PDM) and diabetes mellitus (DM) are common among acute coronary syndrome (ACS) patients. The present study evaluated the association between diabetes status and radial artery (RA) atherosclerosis using optical coherence tomography (OCT) in ACS patients.

METHODS

A total of 335 ACS patients who underwent RA OCT were categorized into the DM group, the PDM group, and the normal glucose metabolism (NGM) group. OCT characteristics and clinical variables were compared.

RESULTS

RA atherosclerotic plaques were more frequent in the PDM and DM groups than in the NGM group (38.7% vs. 33.3% vs. 16.1%, p = 0.001). Lipid and calcified plaque occurrence were significantly more common in the DM group, followed by the PDM and NGM groups (19.3% vs. 14.6% vs. 6.5%, p = 0.027; 11.8% vs. 6.5% vs. 1.1%, p = 0.009). The prevalence of microvessels in the PDM group was significantly higher (42.7% vs 23.7%, p = 0.017) than in the NGM group but was comparable to the DM group. Multivariate analysis revealed that HbA1c level and age were independent predictors of RA plaque formation and eccentric intimal hyperplasia (all p<0.05).

CONCLUSIONS

RA atherosclerosis characteristics differ according to diabetes status. HbA1c level could be a useful marker for RA atherosclerosis progression in ACS 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.

Prognostic irrelevance of plaque vulnerability following plaque sealing in high-risk patients with type 2 diabetes: an optical coherence tomography study

Background

Type 2 diabetes mellitus (T2DM) is associated with an increased cardiovascular risk related at least in part to a more vulnerable plaque phenotype. However, patients with T2DM exhibit also an increased risk following percutaneous coronary intervention (PCI). It is unknown if plaque vulnerability of a treated lesion influences cardiovascular outcomes in patients with T2DM. In this study, we aimed to assess the association of plaque morphology as determined by optical coherence tomography (OCT) with cardiovascular outcome following PCI in high-risk patients with T2DM.

Methods

81 patients with T2DM and OCT-guided PCI were recruited. Pre-interventional OCT and systematic follow-up of median 66.0 (IQR = 8.0) months were performed.

Results

During follow-up, 24 patients (29.6%) died. The clinical parameters age (HR 1.16 per year, 95% CI 1.07–1.26, p < 0.001), diabetic polyneuropathy (HR 3.58, 95% CI 1.44–8.93, p = 0.006) and insulin therapy (HR 3.25, 95% CI 1.21–8.70, p = 0.019) predicted mortality in T2DM patients independently. Among OCT parameters only calcium-volume-index (HR 1.71 per 1000°*mm, 95% CI 1.21–2.41, p = 0.002) and lesion length (HR 1.93 per 10 mm, 95% CI 1.02–3.67, p = 0.044) as parameters describing atherosclerosis extent were significant independent predictors of mortality. However, classical features of plaque vulnerability, such as thickness of the fibrous cap, the extent of the necrotic lipid core and the presence of macrophages had no significant predictive value (all p = ns).

Conclusion

Clinical parameters including those describing diabetes severity as well as OCT-parameters characterizing atherosclerotic extent but not classical features of plaque vulnerability predict mortality in T2DM patients following PCI. These data suggest that PCI may provide effective plaque sealing resulting in limited importance of local target lesion vulnerability for future cardiovascular events in high-risk patients with T2DM.

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.

The association between glucose-related variables and plaque morphology in patients with ST-segment elevated myocardial infarction

Background

Plaque rupture (PR) and plaque erosion (PE) are main causes of acute myocardial infarction with different demographic and histology characteristics and need different treatment strategy. PR and PE can be identified with optical coherence tomography (OCT) accurately, but convenient and effective noninvasive markers for them are rarely found. History of diabetes mellitus (DM) was reported to be a potential predictor of PR in ST-segment elevated myocardial infarction (STEMI) patients, but the predictive value of other glucose-related variables for it is still uncertain. Present study aimed to clear the relationship between some glucose-related variables and plaque morphology in patients with STEMI.

Methods

We consecutively enrolled 872 STEMI patients and divided them into PR group (n = 616) and PE group (n = 256) based on OCT diagnostic criteria. The relationship of glucose-related variables, including random plasma glucose on admission (ARPG), glycosylated hemoglobin (HbA1c), post-PCI fasting plasma glucose (PFPG), DM history, glucose variable tendency (GVT) and the acute-to-chronic glycemic ratio (A/C), to the PR risk of STEMI patients was analyzed. The correlation between the glucose-related variables and plaque morphology was analyzed meanwhile.

Results

Among the glucose-related variables, ARPG and GVT were confirmed to be independent predictors for PR after adjusting for other traditional risk factors in nondiabetic patients. The higher the ARPG level, the more PR risk the STEMI patients had. And high HbA1c and APPG were demonstrated to have a weak and positive correlation with lipid constituents and stenosis degree of culprit vessel.

Conclusions

Compared to HbA1c, DM history, and some other glucose-related variables, ARPG and GVT were risk factors for PR in STEMI patients, especially those without DM. And high HbA1c and ARPG were positively correlated with the development of vulnerable plaque in culprit vessels.

Trial registration Present study is a retrospective one and the population came from the EROSION study of our center previously. It was approved by the Ethics Committee of the Second Affiliated Hospital of Harbin Medical University (Approval reference number, KY2017-249), and all patients provided written informed consent prior to the inclusion in the study and the investigation conformed to the principles outlined in the Declaration of Helsinki.

Severity of Coronary Artery Disease in Prediabetic Patients Undergoing Elective Coronary Angiography

Introduction Our objective was to determine the severity frequency of coronary artery disease (CAD) in prediabetes patients undergoing coronary angiography (CAG) in a catheterization laboratory. Materials and methods This descriptive comparative study was conducted on patients who were planned for elective CAG in the hospital from January 2019 to November 2019. The study includes patients age ≥40 years undergoing elective CAG with or without percutaneous coronary intervention/percutaneous transluminal coronary angioplasty. There were 458 patients (381 men and 77 women) in this study that were categorized into three groups on the basis on their glycated hemoglobin (HbA1c) levels: group I (n = 143) as non-diabetes, group II (n = 110) as prediabetes, and group III (n = 205) as diabetes. The severity of CAD was determined using the Gensini score. Results A total of 458 patients were included. Of these, 44.97% had hypertension; n = 36 (25.17%), n = 48 (43.63%), and n = 122 (59.51%) in group I, group II and group III, respectively (P = .0001). A total of 214 (46.72%) had a smoking history. There was a strong family history of CAD in group II (n = 29, 26.36%) and group III (n = 43, 20.98%). Group II and group III patients had a higher extension of CAD than group I (P = .01). Group II (n = 27, 41.54) and group III (n = 65, 50.39%) had a higher frequency of deployment of two stents compared to group I. Conclusion Coronary artery atherosclerosis disease increases parallel to the HbA1c severity and smoking. The present study emphasizes prediabetes as an independent risk factor for CAD.

Correlation between prediabetes and coronary artery disease severity in patients undergoing elective coronary angiography

Background

Diabetes is a chronic disease that is responsible for a high rate of morbidity and mortality which can be attributed to atherosclerosis and cardiovascular disease. Diabetes is heralded by prediabetes which not only indicates a higher risk of developing diabetes but also increases the burden of cardiovascular disease. The objective was to observe the effect of prediabetes on the severity of coronary artery disease in patients undergoing elective coronary angiography. Seven hundred and thirty-one patients were admitted for elective coronary angiography and/or PCI starting from September 2017 to August 2018. Patients were divided into group A (normoglycemic group, N = 228), group B (prediabetes group, N = 177), and group C (diabetic group, N = 326). Coronary artery disease (CAD) severity including number of vessels affected and atherosclerotic burden by Gensini score were compared among different groups.

Results

The number of vessels affected as well as left main (LM) disease was higher in the prediabetes group when compared to the normoglycemic group (P,=0.001, P = 0.009, respectively) and was comparable to the diabetes group (P = 0.4, P = 0.6, respectively). Prediabetes showed a Gensini score higher than the normoglycemic group (P = 0.0001) with no significant difference when compared to the diabetic group (P = 0.9).

Conclusion

Prediabetes is associated with high atherosclerotic burden and coronary artery disease complexity that is similar to diabetic than normoglycemic individuals.

Risk of coronary artery disease according to glucose abnormality status and prior coronary artery disease in Japanese men

OBJECTIVE

Although glucose abnormality status (GAS), prior coronary artery disease (CAD), and other traditional risk factors affect the incidence of subsequent CAD, their impact in the same cohort has been scantly studied.

RESEARCH DESIGN AND METHODS

We analyzed data from a nationwide claims database in Japan that was accumulated during 2008-2016 involving 138,162 men aged 18-72 years. Participants were classified as having normoglycemia, borderline glycemia, or diabetes mellitus (DM) with prior CAD (CAD+) or without prior CAD (CAD-). Cox regression model identified variables related to the incidence of CAD.

RESULTS

Among CAD-, management of traditional risks differed from those with and without subsequent CAD events. On the other hand, such differences were weaker in borderline glycemia and DM CAD+, and the influence of traditional risk factors on subsequent CAD was not observed. Cox regression model showed that borderline glycemia and DM confer approximately 1.2- and 2.8-fold excess risks of CAD, respectively, compared with CAD- with normoglycemia. CAD+ confers approximately a 5- to 8-fold increased risk. The impacts of DM and prior CAD additively reached a hazard ratio (HR) of 15.74 (95% confidence interval [CI]: 11.82-21.00). However, the HR in those with borderline glycemia and CAD+ was 7.20 (95% CI: 5.01-10.34), which was not different from those with normoglycemia and CAD+.

CONCLUSION

Control status of traditional risk factors and impact on subsequent CAD differ among categories of glycemic status with and without prior CAD. Individualizing treatment strategies is needed in consideration of risk factors, such as GAS and CAD+.

Relationships of coronary culprit-plaque characteristics with duration of diabetes mellitus in acute myocardial infarction: an intravascular optical coherence tomography study

Background

Diabetes mellitus (DM) or pre-diabetes status is closely associated with features of vulnerable coronary lesions in patients with stable coronary heart disease or acute coronary syndrome. However, the association between duration of diabetes and the morphologies and features of vulnerable plaques has not been fully investigated in patients with acute myocardial infarction (AMI).

Methods

We enrolled a total of 279 patients who presented with AMI between March 2017 and March 2019 and underwent pre-intervention optical coherence tomography imaging of culprit lesions. Patients with DM were divided into two subgroups: a Short-DM group with DM duration of < 10 years and a Long-DM group with DM duration of ≥ 10 years. Baseline clinical data and culprit-plaque characteristics were compared between patients without DM (the non-DM group), those in the Short-DM group, and those in the Long-DM group.

Results

Patients with DM represented 34.1% of the study population (95 patients). The Short- and Long-DM groups included 64 (67.4%) and 31 patients (32.6%), respectively. Glycated hemoglobin A1c (HbA1c) levels were significantly higher in the Long-DM group than the Non- or Short-DM groups (8.4% [Long-DM] versus 5.7% [Non-DM] and 7.6% [Short-DM], P < 0.001). In addition, the highest prevalence of lipid-rich plaques, thin-cap fibroatheroma (TCFA), and plaque ruptures of culprit lesions were observed in the Long-DM group (lipid-rich plaques: 80.6% [Long-DM] versus 52.2% [Non-DM] and 62.5% [Short-DM], P = 0.007; TCFA: 41.9% [Long-DM] versus 19.6% [Non-DM] and 31.3% [Short-DM], P = 0.012; plaque rupture: 74.2% [Long-DM] versus 46.7% [Non-DM] and 48.4% [Short-DM], P = 0.017). The frequency of calcification was significantly higher among patients with DM than among those without (62.1% versus 46.2%, P = 0.016); however, no significant differences were found between the DM subgroups (61.3% [Long-DM] versus 62.5% [Short-DM], P = 0.999).

Conclusions

Increased duration of DM combined with higher HbA1c levels influences culprit-plaque characteristics in patients with DM who suffer AMI. These findings might account for the higher risks of cardiac death in DM patients with long disease duration.

Trial registration This study is registered at clinicaltrials.gov as NCT03593928

Intrinsic calcification angle: a novel feature of the vulnerable coronary plaque in patients with type 2 diabetes: an optical coherence tomography study

Background

Coronary calcification is associated with high risk for cardiovascular events. However, its impact on plaque vulnerability is incompletely understood. In the present study we defined the intrinsic calcification angle (ICA) as the angle externally projected by a vascular calcification and analyzed its role as novel feature of coronary plaque vulnerability in patients with type 2 diabetes.

Methods

Optical coherence tomography was used to determine ICA in 219 calcifications from 56 patients with stable coronary artery disease (CAD) and 143 calcifications from 36 patients with acute coronary syndrome (ACS). We then used finite elements analysis to gain mechanistic insight into the effects of ICA.

Results

Minimal (139.8 ± 32.8° vs. 165.6 ± 21.6°, p < 0.001) and mean ICA (164.1 ± 14.3° vs. 176.0 ± 8.4°, p < 0.001) were lower in ACS vs. stable CAD patients. Mean ICA predicted ACS with very good diagnostic efficiency (AUC = 0.840, 95% CI 0.797–0.882, p < 0.001, optimal cut-off 175.9°); younger age (OR 0.95 per year, 95% CI 0.92–0.98, p = 0.002), male sex (OR 2.18, 95% CI 1.41–3.38, p < 0.001), lower HDL-cholesterol (OR 0.82 per 10 mg/dl, 95% CI 0.68–0.98, p = 0.029) and ACS (OR 14.71, 95% CI 8.47–25.64, p < 0.001) were determinants of ICA < 175.9°. A lower ICA predicted ACS (OR for 10°-variation 0.25, 95% CI 0.13–0.52, p < 0.001) independently from fibrous cap thickness, presence of macrophages or extension of lipid core. In finite elements analysis we confirmed that lower ICA causes increased stress on a lesion’s fibrous cap; this effect was potentiated in more superficial calcifications and adds to the destabilizing role of smaller calcifications.

Conclusion

Our clinical and mechanistic data for the first time identify ICA as a novel feature of coronary plaque vulnerability.

Impact of lesion angle on optical coherence tomography findings and clinical outcomes after drug-eluting stent implantation in curved vessels

Tortuous coronary lesions are associated with adverse outcomes after implantation of bare metal or first-generation drug-eluting stents (DESs). We investigated the impact of lesion angle on vessel wall injuries and stent apposition as assessed by optical coherence tomography (OCT) after second- and newer-generation DES implantation. We investigated 95 de novo lesions treated with a single DES (62 platinum-chromium everolimus-eluting stents and 33 bioresorbable-polymer sirolimus-eluting stents). Post-intervention OCT findings were compared between angled lesions (≥ 45°; n = 33) and non-angled lesions (< 45°; n = 62). The 12-month clinical outcomes were also compared between the groups. Cross-sectional OCT analysis revealed that compared to non-angled lesions, angled ones had a significantly higher incidence of intra-stent dissection around the centre of the angle (19.7% vs. 10.8%, p = 0.01) and incomplete stent apposition (ISA) in the distal and proximal sub-segments (10.0% vs. 4.1%, p = 0.002; 15.3% vs. 7.9%, p < 0.001, respectively). Strut-based analysis also showed that angled lesions demonstrated a higher rate of malapposed strut in the distal and proximal sub-segments (3.0% vs. 0.9%, p < 0.001; 4.3% vs. 1.8%, p < 0.001, respectively). The 12 month clinical outcomes were comparable between the groups. Compared to non-angled lesions, angled coronary lesions were associated with a higher incidence of intra-stent dissection and ISA on post-intervention OCT after implantation of second- and newer-generation DESs.

Coronary plaque characteristics and epicardial fat tissue in long term survivors of type 1 diabetes identified by coronary computed tomography angiography

OBJECTIVES

The aim was to assess coronary atherosclerosis, plaque morphology and associations to cardiovascular risk factors and epicardial adipose tissue (EAT) in patients with long duration of type 1 diabetes mellitus (T1DM).

MATERIALS AND METHODS

Eighty-eight patients with ≥ 45 year T1DM duration and 60 controls underwent coronary CT angiography (CCTA) for evaluation of coronary artery plaque volume (total, calcified or mixed/soft), coronary artery calcification score (CAC) and EAT.

RESULTS

Plaques were detected in 75 (85%) T1DM patients and 28 (47%) controls, p < 0.01. Median (interquartile range) plaque volume (mm³) in T1DM vs. controls was: 21.0 (1.0-66.0) vs. 0.2 (0.0-7.1), p < 0.01 for calcified, 0.0 (0.0-8.7) vs. 0.0 (0.0-0.0), p < 0.01 for soft/mixed and 29.5 (3.9-95.8) vs. 0.4 (0.0-7.4), p < 0.01 for total plaque volume. Median CAC was 128 (13-671) vs. 1 (0.0-39.0), p < 0.01 in T1DM vs. controls. Median EAT volume did not differ between the groups; 52.3 (36.1-65.5) cm³ vs. 55 (38.3-79.6), p = 0.20. No association between CAC or plaque volumes and EAT were observed. Low time-weighted LDL-cholesterol and HbA1c for 30 years were associated with having plaque volume < 25th percentile, OR (95% CI) 0.18 (0.05-0.70), p = 0.01 and 0.45 (0.20-1.00), p < 0.05, respectively. Time-weighted LDL-c was linearly associated with CAC (beta 0.82 (95% CI 0.03-1.62), p = 0.04) and total plaque volume (beta 0.77 (95% CI 0.19-1.36), p = 0.01).

CONCLUSION

Long-term survivors of T1DM have a higher prevalence of coronary atherosclerosis compared to controls. Low LDL-cholesterol and HbA1c over time have a protective effect on coronary atherosclerosis. EAT volume was not associated with coronary atherosclerosis in T1DM patients.

Cardiovascular events, diabetes and guidelines: the virtue of simplicity

Cardiovascular (CV) events or their minor syndromes, as various forms of ischemia, are medical emergencies that do not allow enough time for a guiding anamnesis or proper clinical examination, and lead to relying on Treatment Guidelines, but in many situations it is appropriate to deviate from them. Pathological studies have associated 75% of coronary artery events with atherosclerotic plaque rupture; it is now known that rupture alone is not enough for obstruction or occlusion of the vessel lumen. Concomitant conditions are required for the clinical manifestation of cardiovascular disease, including prothrombogenic and dysfunctional endothelium, less fibrinolytic capacity to protect it, increased platelet activation, increased adrenergic tone, microcirculation vasoconstriction, and other countless factors that contribute to thrombus formation, causing ischemia or infarction. But in most cases, repair of plaque rupture and re endothelization of the lesion are asymptomatic and silent. Atherosclerotic process is a chronic and progressive immune inflammation. Most of the therapeutic indications include statins, which cause side effects in 10% of patients, with a range varying between 7 and 21%, according to different authors. Many investigators have proved that statin use contribute to the genesis of diabetes, reports vary between 1 and 46%, where marked elevation of blood glucose fasting levels and glycosylated hemoglobin have been observed, be it by increased tissue resistance to insulin or by reduced β-cell insulin secretion. Physicians should base their indications on the recommendations provided by Guidelines, but they should not forget that every patient is different, and they should not get confused due to lack of time in an emergency nor be influenced by the latest publications or techniques until they have been properly tested.