Progression of coronary artery disease during long-term follow-up of the Swiss Interventional Study on Silent Ischemia Type II (SWISSI II)

Development and Validation of a Risk Nomogram Model for Predicting Revascularization After Percutaneous Coronary Intervention in Patients with Acute Coronary Syndrome

Objective

Percutaneous coronary intervention (PCI) is one of the most effective treatments for acute coronary syndrome (ACS). However, the need for postoperative revascularization remains a major problem in PCI. This study was to develop and validate a nomogram for prediction of revascularization after PCI in patients with ACS.

Methods

A retrospective observational study was conducted using data from 1083 patients who underwent PCI (≥6 months) at a single center from June 2013 to December 2019. They were divided into training (70%; n = 758) and validation (30%; n = 325) sets. Multivariate logistic regression analysis was used to establish a predictive model represented by a nomogram. The nomogram was developed and evaluated based on discrimination, calibration, and clinical efficacy using the concordance statistic (C-statistic), calibration plot and decision curve analysis (DCA), respectively.

Results

The nomogram was comprised of ten variables: follow-up time (odds ratio (OR): 1.01; 95% confidence interval (CI): 1.00-1.03), history of diabetes mellitus (OR: 1.83; 95% CI: 1.25-2.69), serum creatinine level on admission (OR: 0.99; 95% CI: 0.98-1.00), serum uric acid level on admission (OR: 1.005; 95% CI: 1.002-1.007), lipoprotein-a level on admission (OR: 1.0021; 95% CI: 1.0013-1.0029), low density lipoprotein cholesterol level on re-admission (OR: 1.33; 95% CI: 0.10-0.47), the presence of chronic total occlusion (OR: 3.30; 95% CI: 1.93-5.80), the presence of multivessel disease (OR: 4.48; 95% CI: 2.85-7.28), the presence of calcified lesions (OR: 1.63; 95% CI: 1.11-2.39), and the presence of bifurcation lesions (OR: 1.82; 95% CI: 1.20-2.77). The area under the receiver operating characteristic curve values for the training and validation sets were 0.765 (95% CI: 0.732-0.799) and 0.791 (95% CI: 0.742-0.830), respectively. The calibration plots showed good agreement between prediction and observation in both the training and validation sets. DCA also demonstrated that the nomogram was clinically useful.

Conclusion

We developed an easy-to-use nomogram model to predict the risk of revascularization after PCI in patients with ACS. The nomogram may provide useful assessment of risk for subsequent treatment of ACS patients undergoing PCI.

Adverse Cardiac Remodelling after Acute Myocardial Infarction: Old and New Biomarkers

The prevalence of heart failure (HF) due to cardiac remodelling after acute myocardial infarction (AMI) does not decrease regardless of implementation of new technologies supporting opening culprit coronary artery and solving of ischemia-relating stenosis with primary percutaneous coronary intervention (PCI). Numerous studies have examined the diagnostic and prognostic potencies of circulating cardiac biomarkers in acute coronary syndrome/AMI and heart failure after AMI, and even fewer have depicted the utility of biomarkers in AMI patients undergoing primary PCI. Although complete revascularization at early period of acute coronary syndrome/AMI is an established factor for improved short-term and long-term prognosis and lowered risk of cardiovascular (CV) complications, late adverse cardiac remodelling may be a major risk factor for one-year mortality and postponded heart failure manifestation after PCI with subsequent blood flow resolving in culprit coronary artery. The aim of the review was to focus an attention on circulating biomarker as a promising tool to stratify AMI patients at high risk of poor cardiac recovery and developing HF after successful PCI. The main consideration affects biomarkers of inflammation, biomechanical myocardial stress, cardiac injury and necrosis, fibrosis, endothelial dysfunction, and vascular reparation. Clinical utilities and predictive modalities of natriuretic peptides, cardiac troponins, galectin 3, soluble suppressor tumorogenicity-2, high-sensitive C-reactive protein, growth differential factor-15, midregional proadrenomedullin, noncoding RNAs, and other biomarkers for adverse cardiac remodelling are discussed in the review.

Canonical Correlation between Behavioral-Psychological Variables and Predictors of Coronary Artery Disease Prognosis

Metabolic syndrome (MetS) and severity of coronary artery disease (CAD) are considered predictors of CAD prognosis. Unhealthy lifestyles and type-D personality are associated with MetS and are potential causes of primary and secondary CAD. In this cross-sectional descriptive study, we aimed to investigate the relationship between behavioral-psychological variables and predictors of CAD prognosis. The behavioral-psychological variable set contained six lifestyle categories and two type-D personality categories. Descriptive analyses, t-tests, analysis of variance, Pearson’s correlation, and canonical correlation were used. The behavioral-psychological variable set was related to the predictor set for CAD prognosis, with a significant canonical variate of 0.67 (45% overlapping variance). Significant pairs of canonical variates indicated that poor physical activity and weight control (−0.77), poor dietary habits (−0.78), alcohol consumption and cigarette smoking (−0.37), lack of sleep and rest (−0.40), stress (−0.64) in the lifestyle set, higher negative affectivity (0.52), and social inhibition (0.71) in the type-D personality set were associated with a high MetS score (0.59) and severity of CAD (0.91). A combination of behavioral and psychological variables was found to be important in predicting the prognosis of CAD; therefore, interventions aimed at preventing combinations of these variables may be effective in improving CAD prognosis.

Successful revascularization versus medical therapy in diabetic patients with stable right coronary artery chronic total occlusion: a retrospective cohort study

Background

The territory of the right coronary artery (RCA) is smaller than that of the left anterior descending artery. Previous studies have reported conflicting results when considering whether stable RCA-chronic total occlusion (CTO) should be reopened. The coexistence of diabetic and coronary artery diseases represents a severe situation. Therefore, we aimed to determine if stable RCA-CTO in diabetic patients was necessary to be reopened. To our knowledge, no studies have focused on this topic to date.

Methods

We enrolled diabetic patients with RCA-CTO who had clinical presentations of symptomatic stable angina or silent ischemia. RCA-CTO was treated with either successful revascularization (the CTO-SR group) or medical therapy (the CTO-MT group). The primary endpoint was all-cause death. Both Cox regression and propensity score matching analyses were used. Sensitivity analysis was performed based on subgroup populations and relevant baseline variables.

Results

A total of 943 patients were included: 443 (46.98%) patients in the CTO-MT group and 500 (53.02%) patients in the CTO-SR group. After a mid-term follow-up (CTO-SR: 48 months; CTO-MT: 42 months), we found that CTO-SR was superior to CTO-MT in terms of all-cause death (adjusted hazard ratio [HR] [model 1]: 0.429, 95% conference interval [CI] 0.269–0.682; adjusted HR [model 2]: 0.445, 95% CI 0.278–0.714). The superiority of CTO-SR was consistent for cardiac death, possible/definite cardiac death, repeat revascularization, target vessel revascularization (TVR) and repeat nonfatal myocardial infarction. Subgroup analysis confirmed the mortality benefit of CTO-SR by percutaneous coronary intervention (the successful CTO-PCI subgroup, 309 patients in total). While CTO-SR by coronary artery bypass grafting (the CTO-CABG subgroup, 191 patients in total) offered patients more benefit from repeat revascularization and TVR than that offered by successful CTO-PCI.

Conclusions

For stable RCA-CTO patients with diabetes, successful revascularization offered patients more clinical benefits than medical therapy. CTO-CABG might be a more recommended way to accomplish revascularization.

Trial registration This study was not registered in an open access database

Electronic supplementary material

The online version of this article (10.1186/s12933-019-0911-4) contains supplementary material, which is available to authorized users.

Predictors of Coronary Artery Disease Progression among High-risk Patients with Recurrent Symptoms

Background

Despite the availability of new potent medical therapies, the rate of progression of angiographic coronary artery disease (CAD) is not well described. The aim of this analysis is to describe the rate and predictors of progression of CAD among patients with recurrent symptoms.

Materials and Methods

We reviewed 259 patients (mean age 61 ± 11 years, 70% males) who underwent two coronary angiograms between 2008 and 2013. Progressive CAD was defined as obstructive CAD in a previously disease-free segment or new obstruction in a previously nonobstructive segment. Patients who had coronary artery bypass surgery between these two angiograms were excluded from the analysis. Multivariate logistic regression was used to determine the independent predictors of progression of CAD.

Results

The included cohort had a high prevalence of coronary risk factors; hypertension (71%), diabetes (69%), and dyslipidemia (75%). Despite adequate medical therapy, more than half of the patients (61%) had CAD progression. Using multivariate logistic regression, a drop in the left ventricular ejection fraction (LVEF) by more than 5% was the predictor of CAD progression (adjusted odds ratio 5.8, P = 0.042, 95% confidence interval 1.1-31.2).

Conclusion

Among high-risk patients with recurrent symptoms, the short-term rate of progression of CAD is high. A drop in LVEF >5% is a predictor of CAD progression. Further studies are needed to determine the prognostic value of CAD progression in the era of potent medical therapy.

Sex-dependent effects of diabetes mellitus on the revascularization rate in mid-term follow up of young patients with coronary artery disease

AIMS

We investigated the association between Type-2 diabetes mellitus (DM) and the need for revascularization at a 5-year follow-up of young coronary artery disease patients and the role of sex in this regard.

METHODS

Among 1121 young (males≤45, and females≤55years) patients (female: 49.7%) from Tehran Heart Center's Premature Coronary Atherosclerosis Cohort, 371(33.1%) had diabetes prior to angiography. Revascularization was considered as either percutaneous coronary intervention or coronary artery bypass graft surgery.

RESULTS

The mean follow-up duration was 57.67±22.43months. In the univariable analysis, diabetics were at a significantly higher risk of revascularization than nondiabetics (Sub-distributional Hazard Ratio [SHR]=1.843, P value<0.001). There was no association between DM and revascularization among men (SHR=1.232, P value=0.508). In contrast, women with DM had threefold more revascularization risk than women without DM (SHR=3.519, P value<0.001). After adjustment for confounding factors, the risk of revascularization in diabetics compared to nondiabetics increased to 2.139 fold (95% CI=1.473, 3.108) among the whole subjects, remained nonsignificant among men, and increased significantly to 3.725 fold (95% CI=2.067, 6.725) in women.

CONCLUSIONS

Our data showed that in women with premature CAD, but not in men, DM may have a significant role in emerging revascularization during a mean follow-up of 5years.

Is ischemia the only factor predicting cardiovascular outcomes in all diabetes mellitus patients?

Diabetes mellitus (DM) is associated with an excess in cardiovascular morbidity and mortality, and is characterized by increased rates of coronary artery disease. Furthermore, once atherosclerosis is established, this is associated with an increased extent, complexity and a more rapid progression than seen in non-DM patients. Ischemia is the single most important predictor of future hard cardiac events and ischemia correction remains the cornerstone of current revascularization strategies. However recent data suggests that, in DM patients, coronary atherosclerosis despite the absence of ischemia, detected by either invasive or non-invasive methods, may not be associated with the same low risk of future cardiac events as seen in non-DM patients. This review seeks to examine the current evidence supporting an ischemia driven revascularization strategy, and to challenge the notion that ischemia is the only clinically relevant factor in the prediction of cardiovascular outcomes in all-comer DM patients. Specifically, we examine whether in DM patients certain characteristics beyond ischemia, such as microvascular disease, coronary atherosclerosis burden, progression and plaque composition, may need to be considered for a more refined risk stratification in these high-risk patients.

The burden of major adverse cardiac events in patients with coronary artery disease

Background

Patients with a history of cardiovascular disease are at high risk of developing secondary major adverse cardiac events (MACE). This study aimed to identify independent predictors of MACE after hospital admission which could be used to identify of high-risk patients who may benefit from preventive strategies.

Methods

This study included 1,520 consecutive patients with coronary artery disease (CAD) (654 with acute coronary syndrome (ACS) and 866 with elective percutaneous coronary intervention (PCI) patients) who received PCI and/or stenting. MACE was defined as all-cause mortality or rehospitalization for a cardiovascular- related illness. Cardiovascular-related illnesses included heart failure, reinfarction (nonfatal), recurrence of angina pectoris and repeat PCI or coronary artery bypass graft.

Results

During a mean follow-up period of 32 months, 558 of the 1,520 patients developed at least one MACE. Cox regression analysis showed that the baseline clinical and biochemical variables which associated with MACE were age, being illiterate, a widow or widower, and/or economically dependent, having triple vessel disease, stent implantation, anemia, and/or diabetes mellitus, waist to hip ratio (WHR), diastolic blood pressure, fasting glucose, total cholesterol, high-density lipoprotein cholesterol (HDL-C), creatinine, estimated glomerular filtration rate (eGFR), red blood cell count, hemoglobin, hematocrit, and mean corpuscular-hemoglobin concentration (MCHC) in ACS patients, and age, malnourished, and/or economically dependent, taking hypoglycemic medication, having triple vessel disease, stent implantation, anemia, diabetes mellitus, and/or hypertension, WHR, fasting glucose, HDL-C, uric acid, creatinine, eGFR, high-sensitivity C-reactive protein, mean corpuscular volume, and MCHC in elective PCI patients. Using multivariate Cox regression analysis, we found the MACE’s independent factors are triple vessel disease, stent implantation, hypertension, and eGFR in ACS patients, and having triple vessel disease, stent implantation, hypertension, and uric acid in elective PCI patients.

Conclusions

Having triple vessel disease, stent implantation, hypertension, and eGFR or uric acid independently predicted MACE in patients with CAD after long-term follow-up. Fortunately, these factors are modifiable and should be identified and monitored early.

A pan-coronary artery angiographic study of the association between diabetes mellitus and progression or regression of coronary atherosclerosis

The frequency and pattern of progression or regression of coronary atherosclerosis in contemporary patients with diabetes remain unknown. This study included 605 patients with coronary artery disease (CAD). Two coronary angiographic examinations at baseline and after 2 years were performed. The analysis focused on non-stented segments with diameter stenosis ≥25 %. Atherosclerosis progression (or regression) was defined as a decrease (or increase) in the mean minimal lumen diameter (MLD) in the 2-year angiogram compared to mean MLD in the baseline angiogram of >0.2 mm. Statins were prescribed in 576 patients (95.2 %). The primary outcome was atherosclerosis progression or regression in the 2-year angiogram. One hundred sixty-nine patients (28 %) had diabetes. Diabetic patients had greater reduction of mean MLD in the 24 angiogram compared to baseline angiogram than nondiabetic patients (0.11 ± 0.18 vs. -0.08 ± 0.15 mm, P < 0.001). Atherosclerosis progression was observed in 37 patients with diabetes and 16 nondiabetic patients (21.9 vs. 3.7 %; P < 0.001). Atherosclerosis regression was observed in two diabetic patients and 78 nondiabetic patients (1.2 vs. 17.9 %; P < 0.001). A progression pattern across all coronary segments was observed in 70 patients (41.4 %) with diabetes and 60 patients (13.8 %) without diabetes (P < 0.001). Diabetic patients with a low-density lipoprotein cholesterol ≥70 mg/dl showed more atherosclerosis progression than diabetic patients with LDL cholesterol <70 mg/dl (delta-MLD: 0.12 ± 0.19 vs. 0.08 ± 0.16 mm; P = 0.04). In conclusion, in contemporary patients with CAD treated with moderate-intensity statin therapy, diabetes is associated with the increased risk of progression and decreased probability of regression of coronary atherosclerosis.

Association of progression or regression of coronary artery atherosclerosis with long-term prognosis

BACKGROUND

The association between coronary atherosclerosis progression or regression and long-term prognosis remains poorly defined. We assessed the association of atherosclerosis progression or regression with long-term mortality and factors that promote angiographic progression or regression of coronary atherosclerosis in patients with angiographically proven coronary artery disease.

METHODS

The study included 605 patients with coronary artery disease who underwent coronary angiography at baseline and at 2 years later. Pan-coronary artery tree quantitative coronary angiography was performed. Of 6259 coronary segments (10.3 lesions per patient) analyzed, 1790 non-stented segments with ≥25% diameter stenosis at baseline were included. Atherosclerosis progression or regression was defined as a decrease or increase in the mean minimal lumen diameter (MLD) of the non-stented segments of ≥0.2 mm in the 2-year angiography compared to baseline angiography. The primary outcome was all-cause mortality.

RESULTS

Based on the change in mean MLD between baseline and 2-year angiography, patients were divided into 3 groups: the group with progression of atherosclerosis (n=53; 8.8%), the group with no progression or regression of atherosclerosis (n=472; 78.0%) and the group with regression of atherosclerosis (n=80; 13.2%). There were 126 deaths over 8-year follow-up: 17 deaths among patients with progression, 103 deaths among patients with no progression/regression and 6 deaths among patients with regression (Kaplan-Meier estimates of mortality, 37.5%, 25.2% and 8.9%, respectively; adjusted hazard ratio=1.16, 95% confidence interval 1.05 to 1.29, P=.004 for 0.1 mm reduction in mean MLD).

CONCLUSIONS

Progression or regression of coronary atherosclerosis in non-treated coronary segments was significantly associated with 8-year mortality.

Psychosocial interventions for smoking cessation in patients with coronary heart disease

BACKGROUND

This is an update of a Cochrane review previously published in 2008. Smoking increases the risk of developing atherosclerosis but also acute thrombotic events. Quitting smoking is potentially the most effective secondary prevention measure and improves prognosis after a cardiac event, but more than half of the patients continue to smoke, and improved cessation aids are urgently required.

OBJECTIVES

This review aimed to examine the efficacy of psychosocial interventions for smoking cessation in patients with coronary heart disease in short-term (6 to 12 month follow-up) and long-term (more than 12 months). Moderators of treatment effects (i.e. intervention types, treatment dose, methodological criteria) were used for stratification.

SEARCH METHODS

The Cochrane Central Register of Controlled Trials (Issue 12, 2012), MEDLINE, EMBASE, PsycINFO and PSYNDEX were searched from the start of the database to January 2013. This is an update of the initial search in 2003. Results were supplemented by cross-checking references, and handsearches in selected journals and systematic reviews. No language restrictions were applied.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in patients with CHD with a minimum follow-up of 6 months.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility and risk of bias. Abstinence rates were computed according to an intention to treat analysis if possible, or if not according to completer analysis results only. Subgroups of specific intervention strategies were analysed separately. The impact of study quality on efficacy was studied in a moderator analysis. Risk ratios (RR) were pooled using the Mantel-Haenszel and random-effects model with 95% confidence intervals (CI).

MAIN RESULTS

We found 40 RCTs meeting inclusion criteria in total (21 trials were new in this update, 5 new trials contributed to long-term results (more than 12 months)). Interventions consist of behavioural therapeutic approaches, telephone support and self-help material and were either focused on smoking cessation alone or addressed several risk factors (eg. obesity, inactivity and smoking). The trials mostly included older male patients with CHD, predominantly myocardial infarction (MI). After an initial selection of studies three trials with implausible large effects of RR > 5 which contributed to substantial heterogeneity were excluded. Overall there was a positive effect of interventions on abstinence after 6 to 12 months (risk ratio (RR) 1.22, 95% confidence interval (CI) 1.13 to 1.32, I² 54%; abstinence rate treatment group = 46%, abstinence rate control group 37.4%), but heterogeneity between trials was substantial. Studies with validated assessment of smoking status at follow-up had similar efficacy (RR 1.22, 95% CI 1.07 to 1.39) to non-validated trials (RR 1.23, 95% CI 1.12 to 1.35). Studies were stratified by intervention strategy and intensity of the intervention. Clustering reduced heterogeneity, although many trials used more than one type of intervention. The RRs for different strategies were similar (behavioural therapies RR 1.23, 95% CI 1.12 to 1.34, I² 40%; telephone support RR 1.21, 95% CI 1.12 to 1.30, I² 44%; self-help RR 1.22, 95% CI 1.12 to 1.33, I² 40%). More intense interventions (any initial contact plus follow-up over one month) showed increased quit rates (RR 1.28, 95% CI 1.17 to 1.40, I² 58%) whereas brief interventions (either one single initial contact lasting less than an hour with no follow-up, one or more contacts in total over an hour with no follow-up or any initial contact plus follow-up of less than one months) did not appear effective (RR 1.01, 95% CI 0.91 to 1.12, I² 0%). Seven trials had long-term follow-up (over 12 months), and did not show any benefits. Adverse side effects were not reported in any trial. These findings are based on studies with rather low risk of selection bias but high risk of detection bias (namely unblinded or non validated assessment of smoking status).

AUTHORS' CONCLUSIONS

Psychosocial smoking cessation interventions are effective in promoting abstinence up to 1 year, provided they are of sufficient duration. After one year, the studies showed favourable effects of smoking cessation intervention, but more studies including cost-effectiveness analyses are needed. Further studies should also analyse the additional benefit of a psychosocial intervention strategy to pharmacological therapy (e.g. nicotine replacement therapy) compared with pharmacological treatment alone and investigate economic outcomes.

Macrophage Heterogeneity and Plasticity: Impact of Macrophage Biomarkers on Atherosclerosis

Cardiovascular disease (CVD) is a global epidemic, currently representing the worldwide leading cause of morbidity and mortality. Atherosclerosis is the fundamental pathophysiologic component of CVD, where the immune system plays an essential role. Monocytes and macrophages are key mediators in this aspect: due to their heterogeneity and plasticity, these cells may act as either pro- or anti-inflammatory mediators. Indeed, monocytes may develop heterogeneous functional phenotypes depending on the predominating pro- or anti-inflammatory microenvironment within the lesion, resulting in classic, intermediate, and non-classic monocytes, each with strikingly differing features. Similarly, macrophages may also adopt heterogeneous profiles being mainly M1 and M2, the former showing a proinflammatory profile while the latter demonstrates anti-inflammatory traits; they are further subdivided in several subtypes with more specialized functions. Furthermore, macrophages may display plasticity by dynamically shifting between phenotypes in response to specific signals. Each of these distinct cell profiles is associated with diverse biomarkers which may be exploited for therapeutic intervention, including IL-10, IL-13, PPAR-γ, LXR, NLRP3 inflammasomes, and microRNAs. Direct modulation of the molecular pathways concerning these potential macrophage-related targets represents a promising field for new therapeutic alternatives in atherosclerosis and CVD.

The evolution and investigation of native coronary arteries in patients after coronary stent implantation: a study by 320-detector CT angiography

To study the role of 320-detector coronary computed tomography angiography (CTA) in assessing native coronary arteries in patients treated with coronary stents. 123 patients with coronary stenting received both CTA and conventional coronary angiography (CCA) within 1 day. The clinical parameters, coronary calcium scoring, CTA and CCA were analyzed to determine the prevalence of significant stenosis of native coronary arteries (SSNCA), the predictive value of CTA and the factors correlating with SSNCA and newly developed SSNCA after stenting (NDSSNCAS), with CCA as the standard of reference, using both vessel-based analysis (VBA) and patient-based analysis (PBA). Both the source and the reconstructed images were analyzed by CTA. All native coronary arteries were interpretable independent of cardiac motion. CTA showed a sensitivity/specificity of 93.5%/97.3% and 92.5%/92.5% in diagnosing SSNCA in VBA and PBA, respectively. The significant factors related to SSNCA were higher calcium scores (P = 0.003), a higher serum glucose level (P = 0.048), a greater number of vessels without previous stent placement (P = 0.003) and fewer stents implanted within the vessels (P = 0.003). The risk factors showed no significant correlation from PBA on SSNCA or from NDSSNCAS on either VBA or PBA. CTA demonstrates excellent correlation with CCA. The prevalence of SSNCA is significantly correlated with the presence of higher calcium scores in the arteries, a higher serum glucose level, a greater number of vessels without previous stent placement and fewer stents implanted within the vessels; PBA on SSNCA and NDSSNCAS on both VBA and PBA showed no significance.

ARTERIAL ENDOTHELIAL DYSFUNCTION AND MYOCARDIAL ISCHEMIA IN PATIENTS WITH CARBOHYDRATE METABOLISM DISTURBANCES

Aim.To assess the role of vasomotor dysfunction and impaired flowdependent vasodilatation as a risk factor of silent myocardial ischemia (SMI) in patients with Type 2 diabetes mellitus (DM-2).

Material and methods.The study included 128 patients (66 men and 62 women; mean age 59,3±4,7 years), who underwent Holter ECG monitoring, stress test (Bruce protocol), echocardiography, vascular ultrasound, and brachial artery endothelium-dependent vasodilatation (EDVD) assessment.

Results.Patients with coronary heart disease and DM-2 demonstrated reduced EDVD levels (3,7±1,1%) and highly prevalent SMI (93,3%). There was a correlation between EDVD and the number (r=–0,68; p<0,05) or duration of SMI episodes (r=–0,53; p<0,01).

Conclusion.Patients with DM-2 require the assessment of vasomotor endothelial function in order to predict cardiovascular complications. Coronary artery endothelial dysfunction, which manifests in inadequate vasodilatation in response to increased myocardial demand for oxygen, plays an important role in the ischemia development and progression.

Detectable subclinical myocardial necrosis is associated with cardiovascular risk in stable patients with diabetes

OBJECTIVE

To investigate the relationship between different degrees of subclinical myocardial necrosis, glycemic control, and long-term adverse clinical outcomes within a stable patient population with diabetes mellitus.

RESEARCH DESIGN AND METHODS

We examined 1,275 stable patients with diabetes mellitus undergoing elective diagnostic coronary angiography with cardiac troponin I (cTnI) levels below the diagnostic cut-off for defining myocardial infarction (MI) (<0.03 ng/mL). The relationship of subclinical myocardial necrosis (cTnI 0.009-0.029 ng/mL) with incident major adverse cardiovascular events (MACE; defined as any death, MI, or stroke) over 3 years of follow-up was examined.

RESULTS

Subclinical myocardial necrosis was observed in 22% of patients. A strong association was observed between the magnitude of subclinical myocardial necrosis and risk of 3-year incident MACE (hazard ratio, 1.98; 95% confidence interval, 1.48-2.65; P < 0.001) and remained statistically significant even after adjustment for traditional risk factors, high-sensitivity C-reactive protein, and creatinine clearance. Only a weak correlation was observed between the presence of subclinical myocardial necrosis and either glycemic control (r = 0.06; P = 0.044 for hemoglobin A1c versus cTnI) or insulin resistance (r = 0.04; P = 0.094 for glucose-to-insulin ratio versus cTnI).

CONCLUSIONS

The presence of detectable subclinical myocardial necrosis in stable patients with diabetes mellitus is associated with heightened long-term risk for MACE, independent of traditional risk factors and glycemic control.

Ultrasound-assessed non-culprit and culprit coronary vessels differ by age and gender

AIM: To investigate age- and gender-related differences in non-culprit versus culprit coronary vessels assessed with virtual histology intravascular ultrasound (VH-IVUS).

METHODS: In 390 patients referred for coronary angiography to a single center (Luzerner Kantonsspital, Switzerland) between May 2007 and January 2011, 691 proximal vessel segments in left anterior descending, circumflex and/or right coronary arteries were imaged by VH-IVUS. Plaque burden and plaque composition (fibrous, fibro-fatty, necrotic core and dense calcium volumes) were analyzed in 3 age tertiles, according to gender and separated for vessels containing non-culprit or culprit lesions. To classify as vessel containing a culprit lesion, the patient had to present with an acute coronary syndrome, and the VH-IVUS had to be performed in a vessel segment containing the culprit lesion according to conventional coronary angiography.

RESULTS: In non-culprit vessels the plaque burden increased significantly with aging (in men from 37% ± 12% in the lowest to 46% ± 10% in the highest age tertile, P < 0.001; in women from 30% ± 9% to 40% ± 11%, P < 0.001); men had higher plaque burden than women at any age (P < 0.001 for each of the 3 age tertiles). In culprit vessels of the lowest age tertile, plaque burden was significantly higher than that in non-culprit vessels (in men 48% ± 6%, P < 0.001 as compared to non-culprit vessels; in women 44% ± 18%, P = 0.004 as compared to non-culprit vessels). Plaque burden of culprit vessels did not significantly change during aging (plaque burden in men of the highest age tertile 51% ± 9%, P = 0.523 as compared to lowest age tertile; in women of the highest age tertile 49% ± 8%, P = 0.449 as compared to lowest age tertile). In men, plaque morphology of culprit vessels became increasingly rupture-prone during aging (increasing percentages of necrotic core and dense calcium), whereas plaque morphology in non-culprit vessels was less rupture-prone and remained constant during aging. In women, necrotic core in non-culprit vessels was very low at young age, but increased during aging resulting in a plaque morphology that was very similar to men. Plaque morphology in culprit vessels of young women and men was similar.

CONCLUSION: This study provides evidence that age- and gender-related differences in plaque burden and plaque composition significantly depend on whether the vessel contained a non-culprit or culprit lesion.

Correlation between major adverse cardiac events and coronary plaque characteristics

BACKGROUND

Unstable plaque is believed to be responsible for major adverse cardiac events (MACE).

OBJECTIVE

To determine whether coronary computed tomography angiography (CCTA) could be used to predict future MACE.

METHODS

Patients undergoing CCTA between January 2008 and February 2010 were consecutively enrolled in the study. The hospital database was screened for patients who later developed acute ST segment elevation myocardial infarction (STEMI), non-STEMI (NSTEMI) or cardiac death. Plaque scores were calculated and analyzed using one-way ANOVA to examine the relationship between plaque scores and MACE.

RESULTS

Of the 8557 patients who underwent CCTA, 1055 had hospital records available for follow-up. During follow-up, 25 patients experienced MACE including death (six patients), heart failure (two patients), STEMI (11 patients) and NSTEMI (six patients). The plaque scores were significantly increased in patients who later died, developed heart failure or experienced STEMI (P<0.05). Calcification, erosion and severe stenosis were responsible for the events (P<0.05). Mild and moderate lesions, positive remodelling, drug-eluting stent placement, occlusion and diffuse lesions were not predictive of MACE (P>0.05).

CONCLUSION

Severe calcification, erosion and severe stenosis predict death, heart failure and STEMI.

Associations of reactive hyperemia index and intravascular ultrasound-assessed coronary plaque morphology in patients with coronary artery disease

Although reactive hyperemia index (RHI) predicts future coronary events, associations with intravascular ultrasound (IVUS)-assessed coronary plaque structure have not been reported. This study therefore investigated associations between RHI and IVUS-assessed coronary plaques. In 362 patients RHI was measured by noninvasive peripheral arterial tonometry and coronary plaque components (fibrous, fibrofatty, necrotic core, and dense calcium) were identified by IVUS in 594 vessel segments of the left anterior descending, circumflex, and/or right coronary arteries. RHI values <1.67 were considered abnormal. Analysis of variance was used to detect independent associations between RHI and plaque composition. Patients with an abnormal RHI had greater plaque burden (41% vs 39% in patients with normal RHI, p = 0.047). Compared to patients with normal RHI, plaque of patients with abnormal RHI had more necrotic core (21% vs 17%, p <0.001) and dense calcium (19% vs 15%, p <0.001) and less fibrous (49% vs 54%, p <0.001) and fibrofatty (11% vs 14%, p = 0.002) tissue. After adjustment for age, gender, cardiovascular risk factors, and drug therapy, abnormal RHI remained significantly associated with fibrous (F ratio 14.79, p <0.001), fibrofatty (F ratio 5.66, p = 0.018), necrotic core (F ratio 14.47, p <0.001), and dense calcium (F ratio 10.80, p = 0.001) volumes. In conclusion, coronary artery plaques of patients with abnormal RHI had a larger proportion of necrotic core and dense calcium. The association of an abnormal RHI with a plaque structure that is more prone to rupture may explain why these patients exhibit a greater risk of coronary events.

Deviation from Murray's law is associated with a higher degree of calcification in coronary bifurcations

OBJECTIVE

Murray's law describes the optimal branching anatomy of vascular bifurcations. If Murray's law is obeyed, shear stress is constant over the bifurcation. Associations between Murray's law and intravascular ultrasound (IVUS) assessed plaque composition near coronary bifurcations have not been investigated previously.

METHODS

In 253 patients plaque components (fibrous, fibro-fatty, necrotic core, and dense calcium) were identified by IVUS in segments proximal and distal to the bifurcation of a coronary side branch. The ratio of mother to daughter vessels was calculated according to Murray's law (Murray ratio) with a high Murray ratio indicating low shear stress. Analysis of variance was used to detect independent associations of Murray ratio and plaque composition.

RESULTS

Patients with a high Murray ratio exhibited a higher relative amount of dense calcium and a lower amount of fibrous and fibro-fatty tissue than those with a low Murray ratio. After adjustment for age, sex, cardiovascular risk factors or concomitant medications, the Murray ratio remained significantly associated with fibrous volume distal (F-ratio 4.90, P=0.028) to the bifurcation, fibro-fatty volume distal (F-ratio 4.76, P=0.030) to the bifurcation, and dense calcium volume proximal (F-ratio 5.93, P=0.016) and distal (F-ratio 5.16, P=0.024) to the bifurcation.

CONCLUSION

This study shows that deviation from Murray's law is associated with a high degree of calcification near coronary bifurcations. Individual deviations from Murray's law may explain why some patients are prone to plaque formation near vessel bifurcations.

Acute myocardial infarction late following stent implantation: Incidence, mechanisms and clinical presentation

Acute myocardial infarction (AMI) can occur late following stent implantation with an incidence up to >6% at 3-4 years, with no difference between DES and BMS. AMI can originate either from the stented site or from disease progression at nonstented sites. Restenosis, against previous thoughts, can lead to AMI. Stent thrombosis occurs with similar overall frequency following DES and BMS implantations, although a higher very late stent thrombosis with DES has been observed. Dissimilar mechanisms between BMS and DES thrombosis are very likely, with impaired neointimal healing being the rule for DES but the exemption for BMS. The use of invasive imaging techniques is useful in elucidating the involved mechanism. Disease progression is a particularly important cause of AMI late post stenting. The angiographic study depicted stent failure and disease progression equally implicated in the AMI late post stenting. When the AMI underlying mechanism is stent thrombosis, it usually occurs earlier and more frequently presented as STEMI compared to the other causes of AMI. The AMI caused by restenosis is more often presented as nonSTEMI, while disease progression leads to AMI later than the other causes. Further research should address equally not only the stent related inadequacies but also disease progression as causes of the future AMI. Angiographic follow-up and intracoronary imaging seem the most appropriate methods to define the exact pathophysiologic mechanism responsible for the AMI post stenting.

Long-term outcome of percutaneous coronary intervention: the significance of native coronary artery disease progression

The extensive use of stents during percutaneous coronary intervention (PCI) is associated with concerns about their potential adverse effects. In-stent restenosis and stent thrombosis definitely significantly affect the PCI outcome. However, review of recent relevant studies suggests that stent-related problems may have been somewhat overestimated when compared to coronary artery disease (CAD) progression at nonstented coronary segments as causative factors of adverse cardiac clinical events late (>30 days) post-PCI. Both stent-related problems and native CAD progression have to be equally addressed to optimize the PCI clinical benefit.