American College of Cardiology/American Heart Association Expert Consensus document on electron-beam computed tomography for the diagnosis and prognosis of coronary artery disease

Continuous Positive Airway Pressure but Not GLP1-mediated Weight Loss Improves Early Cardiovascular Disease in Obstructive Sleep Apnea: A Randomized Proof-of-Concept Study

Rationale: Obstructive sleep apnea (OSA) is an independent risk factor for cardiovascular (CV) morbidity and mortality, but the benefit of continuous positive airway pressure (CPAP) is uncertain. However, most randomized controlled trials have focused on the role of CPAP in secondary prevention, although there is growing evidence of a potential benefit on early CV disease. Weight loss in combination with CPAP may be superior but is difficult to achieve and maintain with conventional measures alone. Objectives: The aim of this study was to gain insights into the effect of CPAP on early atherosclerotic processes and to compare it with a glucagon-like peptide (GLP)-1-mediated weight loss regimen in patients with OSA. Methods: We performed a randomized proof-of-concept study comparing CPAP, a GLP1-mediated weight-loss regimen (liraglutide [Lir]), and both in combination for 24 weeks in 30 consecutive patients with OSA (apnea-hypopnea index >15 events/h; body mass index 30-40 kg/m2; and no history of diabetes, heart failure, or unstable CV disease). In addition to extensive evaluation for CV risk factors and endothelial function at baseline and end of study, subjects underwent 18F-fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography (18F-FDG PET-CT) for the measurement of aortic wall inflammation (target-to-background ratio) and coronary computed tomography angiography for semiautomated coronary plaque analysis. Results: Baseline characteristics were similar between groups. CPAP alone and in combination resulted in greater reduction in apnea-hypopnea index than Lir alone (mean difference, -45 and -43 events/h, respectively, vs. -12 events/h; P < 0.05). Both Lir and combination treatment led to significant weight loss, but only CPAP alone resulted in significant decrease in vascular inflammation (aortic wall target-to-background ratio from 2.03 ± 0.34 to 1.84 ± 0.43; P = 0.010), associated with an improvement in endothelial function and a decrease in C-reactive protein. Low-attenuation coronary artery plaque volume as a marker of unstable plaque also decreased with CPAP (from 571 ± 490 to 334 ± 185 mm3) and with combination therapy (from 401 ± 145 to 278 ± 126 mm3) but not with Lir. Conclusions: These data suggest that CPAP therapy, but not GLP1-mediated weight loss, improves vascular inflammation and reduces unstable plaque volume in patients with OSA. Further large randomized controlled studies are warranted to assess the benefit of CPAP therapy in modifying early CV disease. Clinical trial registered with www.clinicaltrials.gov (NCT04186494).

Relation between Coronary Artery Calcium Score and Cardiovascular Events in Hodgkin Lymphoma Survivors: A Cross-Sectional Matched Cohort Study

BACKGROUND

Thoracic radiotherapy is one of the corner stones of HL treatment, but it is associated with increased risk of cardiovascular events. As HL is often diagnosed at a young age, long-term follow-up including screening for coronary artery disease (CAD) is recommended.

OBJECTIVES

This study aims to evaluate the presence of coronary artery calcium score (CACS) in relation to cardiovascular events in HL patients treated with thoracic radiotherapy compared to a non-cancer control group.

METHODS

Consecutive HL patients who underwent evaluation for asymptomatic CAD with coronary computed tomography angiography > 10 years after thoracic irradiation were included. The study population consisted of 97 HL patients matched to 97 non-cancer patients on gender, age, cardiovascular risk factors, and statin use.

RESULTS

Mean age during CT scan in the HL population was 45.5 ± 9.9 and in the non-cancer population 45.5 ± 10.3 years. CACS was elevated (defined as >0) in 49 (50.5%) HL patients and 30 (30.9%) control patients. HL survivors had an odds ratio of 2.28 [95% CI: 1.22-4.28] for having a CACS > 0 compared to the matched population (p = 0.006). Prevalence of CACS > 90th percentile differed significantly: 17.1% in HL survivors vs. 4.6% in the matched population (p = 0.009). Non-obstructive coronary artery stenosis was more prevalent in the HL population than in the control population (45.7% vs. 28.4%, respectively, p = 0.01). During follow-up of 8.5 [5.3; 9.9] years, nine HL patients experienced an event including two patients with a CACS of zero. No events occurred in the control population.

CONCLUSION

In a matched study population, HL survivors have a higher prevalence of a CACS > 0 and an increased risk of cardiovascular events after thoracic irradiation compared to a matched non-cancer control group.

Transcription factor 21 accelerates vascular calcification in mice by activating the IL-6/STAT3 signaling pathway and the interplay between VSMCs and ECs

Vascular calcification is caused by the deposition of calcium salts in the intimal or tunica media layer of the aorta, which increases the risk of cardiovascular events and all-cause mortality. However, the mechanisms underlying vascular calcification are not fully clarified. Recently it has been shown that transcription factor 21 (TCF21) is highly expressed in human and mouse atherosclerotic plaques. In this study we investigated the role of TCF21 in vascular calcification and the underlying mechanisms. In carotid artery atherosclerotic plaques collected from 6 patients, we found that TCF21 expression was upregulated in calcific areas. We further demonstrated TCF21 expression was increased in an in vitro vascular smooth muscle cell (VSMC) osteogenesis model. TCF21 overexpression promoted osteogenic differentiation of VSMC, whereas TCF21 knockdown in VSMC attenuated the calcification. Similar results were observed in ex vivo mouse thoracic aorta rings. Previous reports showed that TCF21 bound to myocardin (MYOCD) to inhibit the transcriptional activity of serum response factor (SRF)-MYOCD complex. We found that SRF overexpression significantly attenuated TCF21-induced VSMC and aortic ring calcification. Overexpression of SRF, but not MYOCD, reversed TCF21-inhibited expression of contractile genes SMA and SM22. More importantly, under high inorganic phosphate (3 mM) condition, SRF overexpression reduced TCF21-induced expression of calcification-related genes (BMP2 and RUNX2) as well as vascular calcification. Moreover, TCF21 overexpression enhanced IL-6 expression and downstream STAT3 activation to facilitate vascular calcification. Both LPS and STAT3 could induce TCF21 expression, suggesting that the inflammation and TCF21 might form a positive feedback loop to amplify the activation of IL-6/STAT3 signaling pathway. On the other hand, TCF21 induced production of inflammatory cytokines IL-1β and IL-6 in endothelial cells (ECs) to promote VSMC osteogenesis. In EC-specific TCF21 knockout (TCF21ECKO) mice, VD3 and nicotine-induced vascular calcification was significantly reduced. Our results suggest that TCF21 aggravates vascular calcification by activating IL-6/STAT3 signaling and interplay between VSMC and EC, which provides new insights into the pathogenesis of vascular calcification. TCF21 enhances vascular calcification by activating the IL-6-STAT3 signaling pathway. TCF21 inhibition may be a new potential therapeutic strategy for the prevention and treatment of vascular calcification.

Correlation Between Intracranial Calcification and Extracranial Stenosis of the Internal Carotid Artery

Intracranial artery calcification is a marker of vascular atherosclerosis and has a high prevalence worldwide. Both atherosclerosis of the internal carotid artery at the carotid sinus in the neck and intracranial calcification have been associated with ischemic stroke. The relationship between the two has not been well studied. The present study investigated how carotid sinus narrowing could relate to calcification located in the distal intracranial artery at the cavernous carotid. We examined a population not selected for cerebral disease. This retrospective study contained 179 subjects aged 18 years and older from the Hawaii Diagnostic Radiology database. Extracranial internal carotid artery stenosis was determined using the absolute diameter, North American Symptomatic Carotid Endarterectomy Trial, and common carotid artery methods. Calcification was scored using the modified Woodcock method. A positive correlation between intracranial calcification and extracranial carotid stenosis was found using all three methods. Individuals with intracranial calcification were more likely to be older, have a smaller internal carotid artery diameter, and have a greater percent stenosis at the internal carotid artery than those without intracranial artery calcification (p<0.001 for all). These results may help refocus interest in calcification in studies of cerebral vasculature and its correlation with extracranial carotid stenosis.

Sex-specific performance of the ASCVD pooled cohort equation risk calculator as a correlate of coronary artery calcium in Kampala, Uganda

INTRODUCTION

The prevalence of cardiovascular disease (CVD) is rising in Sub-Saharan Africa, but it is not known whether current risk assessment tools predict coronary atherosclerosis in the region. Furthermore, sex-specific performance and interaction with HIV serostatus has not been well studied.

METHODS

This cross-sectional study compared ASCVD risk scores and detectable coronary artery calcium (CAC>0) by sex in Kampala, Uganda (n = 200). The cohort was enriched for persons living with HIV, and all participants had at least one CVD risk factor. We fit log binomial regression models and constructed ROC curves to assess the correlation between ASCVD scores and CAC>0.

RESULTS

The mean age was 56. 62% were female and 50% of both men and women were living with HIV. The median 10-year ASCVD risk score was significantly higher in men (11.0%, IQR 7.6-19.4%) than in women (5.1%, IQR 3.2-8.7%), although the prevalence of CAC>0 was similar (8.1 vs 10.5%, p = 0.63). Each 10% increase in ASCVD risk was associated with increased risk of CAC>0 in men (PR 1.59, 95% CI 1.00-2.55, p = 0.05) but not women (PR 1.15, 95% CI 0.44-3.00, p = 0.77). ROC curves demonstrated an AUC of 0.57 for women vs 0.70 for men. Adjustment for HIV serostatus improved the predictive value of ASCVD in women only (AUC 0.78, p = 0.02).

CONCLUSIONS

ASCVD risk score did not correlate with the presence of CAC in women. When HIV status was added to the ASCVD risk score, correlation with CAC was improved in women but not in men.

Coronary Calcium Risk Score and Cardiovascular Risk

The association between the presence of coronary artery calcium (CAC) and the risk of coronary artery disease (CAD) has been appreciated for decades. In this review, we critically appraise the role of CAC based on computerized tomography in contemporary risk stratification. Available evidence suggests that the measurement of CAC is a useful modality in many patients for more precise risk stratification and prognostic determination. Whether newer CAC score incorporating extra coronary calcification will add incremental value, especially for stroke and other non-coronary vascular outcomes, needs a prospective study.

Value of Coronary Calcium Scoring in Symptomatic and Asymptomatic Coronary Artery Disease Patients

AIM AND OBJECTIVE

The study aimed to estimate the relationship between Coronary Calcium Scoring (CCS) and the presence of different degrees of obstructive coronary artery disease (CAD) to avoid unnecessary examinations and hence unnecessary radiation exposure and contrast injection.

BACKGROUND

Coronary Calcium Scoring (CCS) is a test that uses x-ray equipment to produce pictures of the coronary arteries to determine the degree of its narrowing by the build-up of calcified plaques. Despite the lack of definitive data linking ionizing radiation with cancer, the American Heart Association supports widely that practitioners of Computed tomography Coronary Angiography (CTCA) should keep "patient radiation doses as low as reasonably achievable but consistent with obtaining the desired medical information".

METHODS

Data obtained from 275 CTCA examinations were reviewed. Radiation effective doses were estimated for both CCS and CTCA, and measures to keep them as low as possible were presented. CCS and Framingham risk estimates were compared to obtain the final results of CTCA to detect sensitivity and specificity of each one in detecting obstructive lesions.

RESULTS

CCS is a strong discriminator for obstructive CAD with high sensitivity and specificity and correlates well with the degree of obstruction even more than Framingham risk estimate, which has high sensitivity and low specificity.

CONCLUSION

CCS helps to reduce the effective radiation dose if properly evaluated to skip unnecessary CTCA if obstructive lesions are unlikely, and this as a test does not use contrast material, thus harmful effect on the kidney will be avoided as most of the coronary atherosclerotic patients have renal problems.

Erectile dysfunction and coronary artery calcification in incident dialysis patients

PURPOSE

Erectile dysfunction, which has been associated with mortality in the general population, is common in individuals on hemodialysis. Our aim was to determine the relationship between erectile dysfunction, coronary artery calcification and mortality in incident hemodialysis patients.

MATERIALS AND METHODS

A prospective cohort of incident adult dialysis patients with no history of coronary artery disease underwent coronary artery calcification measurement by ECG-triggered multi-slice computed tomography (MSCT) scan at baseline and at least 12 months later. Erectile dysfunction was determined using the 15-item validated International Index of Erectile Function (IIEF-15) questionnaire.

RESULTS

Erectile dysfunction was prevalent in 83% of patients, with 43% classified as severe erectile dysfunction, 22.4% as moderate erectile dysfunction, and 17.2% as mild erectile dysfunction. The median (IQR) coronary artery calcification score was 43.4 (0.25-353.8) for those with erectile dysfunction and 0 (0-0) for those without erectile dysfunction (p = 0.007). More than half (55.6%) of the patients with erectile dysfunction experienced progression of coronary artery calcification compared to 14.3% of patients without erectile dysfunction (p = 0.05). Mortality was 21% during an average follow-up of 5.2 (1.3) years. Twenty-three percent of patients with erectile dysfunction died compared to 10% of people without erectile dysfunction (p = 0.4). Erectile dysfunction was not significantly associated with mortality [HR 1.2 (1.3), p = 0.87].

CONCLUSIONS

Erectile dysfunction is common in individuals who start dialysis. It is significantly associated with an increased coronary artery calcification score, however, it is not associated with increased mortality in incident dialysis patients with no history of coronary artery disease.

ERK1/2 inhibition reduces vascular calcification by activating miR-126-3p-DKK1/LRP6 pathway

Rationale: Vascular microcalcification increases the risk of rupture of vulnerable atherosclerotic lesions. Inhibition of ERK1/2 reduces atherosclerosis in animal models while its role in vascular calcification and the underlying mechanisms remains incompletely understood.

Methods: Levels of activated ERK1/2, DKK1, LRP6 and BMP2 in human calcific aortic valves were determined. ApoE deficient mice received ERK1/2 inhibitor (U0126) treatment, followed by determination of atherosclerosis, calcification and miR-126-3p production. C57BL/6J mice were used to determine the effect of U0126 on Vitamin D₃ (VD₃)-induced medial arterial calcification. HUVECs, HAECs and HASMCs were used to determine the effects of ERK1/2 inhibitor or siRNA on SMC calcification and the involved mechanisms.

Results: We observed the calcification in human aortic valves was positively correlated to ERK1/2 activity. At cellular and animal levels, U0126 reduced intimal calcification in atherosclerotic lesions of high-fat diet-fed apoE deficient mice, medial arterial calcification in VD₃-treated C57BL/6J mice, and calcification in cultured SMCs and arterial rings. The reduction of calcification was attributed to ERK1/2 inhibition-reduced expression of ALP, BMP2 and RUNX2 by activating DKK1 and LRP6 expression, and consequently inactivating both canonical and non-canonical Wnt signaling pathways in SMCs. Furthermore, we determined ERK1/2 inhibition activated miR-126-3p production by facilitating its maturation through activation of AMPKα-mediated p53 phosphorylation, and the activated miR-126-3p from ECs and SMCs played a key role in anti-vascular calcification actions of ERK1/2 inhibition.

Conclusions: Our study demonstrates that activation of miR-126-3p production in ECs/SMCs and interactions between ECs and SMCs play an important role in reduction of vascular calcification by ERK1/2 inhibition.

Risk factors for myocardial injury and death in patients with COVID-19: insights from a cohort study with chest computed tomography

AIMS

Whether pulmonary artery (PA) dimension and coronary artery calcium (CAC) score, as assessed by chest computed tomography (CT), are associated with myocardial injury in patients with coronavirus disease 2019 (COVID-19) is not known. The aim of this study was to explore the risk factors for myocardial injury and death and to investigate whether myocardial injury has an independent association with all-cause mortality in patients with COVID-19.

METHODS AND RESULTS

This is a single-centre cohort study including consecutive patients with laboratory-confirmed COVID-19 undergoing chest CT on admission. Myocardial injury was defined as high-sensitivity troponin I >20 ng/L on admission. A total of 332 patients with a median follow-up of 12 days were included. There were 68 (20.5%) deaths; 123 (37%) patients had myocardial injury. PA diameter was higher in patients with myocardial injury compared with patients without myocardial injury [29.0 (25th-75th percentile, 27-32) mm vs. 27.7 (25-30) mm, P < 0.001). PA diameter was independently associated with an increased risk of myocardial injury [adjusted odds ratio 1.10, 95% confidence interval (CI) 1.02-1.19, P = 0.01] and death [adjusted hazard ratio (HR) 1.09, 95% CI 1.02-1.17, P = 0.01]. Compared with patients without myocardial injury, patients with myocardial injury had a lower prevalence of a CAC score of zero (25% vs. 55%, P < 0.001); however, the CAC score did not emerge as a predictor of myocardial injury by multivariable logistic regression. Myocardial injury was independently associated with an increased risk of death by multivariable Cox regression (adjusted HR 2.25, 95% CI 1.27-3.96, P = 0.005). Older age, lower estimated glomerular filtration rate, and lower PaO2/FiO2 ratio on admission were other independent predictors for both myocardial injury and death.

CONCLUSIONS

An increased PA diameter, as assessed by chest CT, is an independent risk factor for myocardial injury and mortality in patients with COVID-19. Myocardial injury is independently associated with an approximately two-fold increased risk of death.

Largely Accelerated Arterial Aging in Rheumatoid Arthritis Is Associated With Inflammatory Activity and Smoking in the Early Stage of the Disease

Background: Rheumatoid arthritis (RA) patients have a shorter life expectancy than the general population primarily due to cardiovascular comorbidities.

Objectives: To characterize arterial aging in RA.

Patients and Methods: Coronary calcium score (CCS) were available from 112 RA patients; out of these patients, follow-up CCS were measured for 54 randomly selected individuals. Control CCS were obtained from the MESA database (includes 6,000 < participants); arterial age was calculated from CCS.

Results: RA patients were significantly older (10.45 ± 18.45 years, p < 0.001) in terms of the arterial age than the age-, gender-, and race-matched controls. The proportion of RA patients who had zero CCS was significantly less (p < 0.01) than that of those in the MESA reference group. Each disease year contributed an extra 0.395 years (p < 0.01) on the top of the normal aging process. However, the rate of the accelerated aging is not uniform, in the first years of the disease it is apparently faster. Smoking (p < 0.05), previous cardiovascular events (p < 0.05), and high blood pressure (p < 0.05) had additional significant effect on the aging process. In the follow-up study, inflammatory disease activity (CRP > 5 mg/L, p < 0.05) especially in smokers and shorter than 10 years of disease duration (p = 0.05) had the largest impact.

Conclusion: Arterial aging is faster in RA patients than in control subjects, particularly in the first 10 years of the disease. Inflammation, previous cardiovascular events, and smoking are additional contributing factors to the intensified coronary atherosclerosis progression. These data support that optimal control of inflammation is essential to attenuate the cardiovascular risk in RA.

Thickness of epicardial and pericoronary adipose tissue measured using 128-slice MSCT as predictors for risk of significant coronary artery diseases

Aim

Determination the relationship between the epicardial adipose tissue thickness (EATT) and pericoronary adipose tissue thickness (PATT) and the risk of significant coronary artery diseases (CAD) using the coronary artery calcium score (CACS).

Materials and methods

The study group consisted of 80 patients. The risk of significant CAD was estimated based on CACS. Adipose tissue thickness was measured based on multiplanar reformation (MPR), left ventricle short axis and mid-chamber level. EATT in the middle of the length of the right ventricular free wall, PATT around the left anterior descending (LAD), around the left circumflex (LCX) and around the right coronary artery in the posterior interventricular sulcus (RCA).

Results

The median (IQR) values of CACS and EATT were 12.00 (97.90) and 8.65 (3.90) mm. It was found that in the subgroup CACS = 0 statistically significantly lower than in the subgroup CACS > 0 were mean values EATT and PATT RCA. Based on the regression analysis, it was demonstrated that higher CACS is associated with higher EATT, independent of older age and higher BMI. On the basis the ROC curve analysis, the highest prediction sensitivity of 98.4% was demonstrated for EATT ≥ 16.7 mm as a predictor of high risk of significant CAD and the highest specificity of 61.5% for the criterion EATT ≤ 8.7 mm as a predictor of practically no risk of significant CAD.

Conclusion

There is a positive relationship between the risk of a significant CAD estimated based on the coronary artery calcium score and the epicardial adipose tissue thickness.

Intracranial Calcification is Predictive for Hemorrhagic Transformation and Prognosis After Intravenous Thrombolysis in Non-Cardioembolic Stroke Patients

Aim: Hemorrhagic transformation is the major complication of intravenous thrombolysis. Calcification is used widely as an imaging indicator of atherosclerotic burden and cerebrovascular function. The relationship between intracranial calcification and hemorrhagic transformation has not been explored fully. We aimed to identify and quantify calcification in the main cerebral vessels to investigate the correlations between quantitative calcification parameters, hemorrhagic transformation, and prognosis.

Methods: Acute, non-cardiogenic, ischemic stroke patients with anterior circulation who received intravenous thrombolysis therapy in the First Hospital of Jilin University were retrospectively and consecutively included. All included patients underwent a baseline CT before intravenous thrombolysis and a follow-up CT at 24 hours. A third-party software, ITK-SNAP, was used to segment and measure the calcification volume. A vascular nonbone component with a CT value > 130 HU was considered calcified. Hemorrhagic transformation was determined based on the ECASS II classification criteria.

Results: The study included 242 patients, 214 of whom were identified as having calcification. Thirty-one patients developed hemorrhagic transformation. The calcification volume on the lesion side (0.1ml) was associated with hemorrhagic transformation (p = 0.004, OR= 1.504, 95% CI: 1.140–1.985). Ninety-six patients had poor prognoses. The poor prognosis group had more calcified vessels than the good prognosis group (p = 0.014, OR= 1.477, 95% CI: 1.083–2.015).

Conclusions: The arterial calcification volume on the lesion side is associated with hemorrhagic transformation after thrombolysis. The higher the number of calcified vessels, the greater the risk of poor prognosis.

Serum uric acid is independently associated with aortic arch calcification in a cross-sectional study of middle-aged and elderly women

BACKGROUND AND AIMS

The increased serum uric acid (SUA) level is associated with the prevalence of cardiovascular disease (CVD) risks. Aortic arch calcification (AAC) reflects subclinical coronary atherosclerosis and is linked to subsequent cardiovascular morbidity and mortality risks closely. To better understand the role of SUA on arteriosclerosis and CVD, we aim to determine the association between SUA and the presence of AAC.

METHODS AND RESULTS

A total of 5920 individuals aged >45 years old without prior CVD disease were included. The prevalence rate of AAC was 14.4% in all participants and a significantly increasing trend for AAC prevalence rate was found across the SUA tertiles (p < 0.001 for trend). Subsequent subgroup analyses revealed that this positive association trend was only significant in female subjects. After adjusting for confounders, SUA is an independent predictor for the presence of AAC in overall participants and in women.

CONCLUSION

SUA is independently associated with AAC in middle-aged and elderly population, especially in the women. More research needs to determine whether lower thresholds for CVD risk screening for those middle-aged and elderly women with higher SUA tertile even without hyperuricemia are warranted.

Interactive and Multifactorial Mechanisms of Calcific Vascular and Valvular Disease

Calcific vascular and valvular disease (CVVD) is widespread and has major health consequences. Although coronary artery calcification has long been associated with hyperlipidemia and increased mortality, recent evidence suggests that its progression is increased in association with cholesterol-lowering HMG-CoA reductase inhibitors ('statins') and long-term, high-intensity exercise. A nationwide trial showed no cardiovascular benefit of vitamin D supplements. Controversy remains as to whether calcium deposits in plaque promote or prevent plaque rupture. CVVD appears to occur through mechanisms similar to those of intramembranous, endochondral, and osteophytic skeletal bone formation. New evidence implicates autotaxin, endothelial-mesenchymal transformation, and microRNA and long non-coding RNA (lncRNA) as novel regulatory factors. New therapeutic options are being developed.

The Association of Water-Pipe Smoking and Coronary Artery Calcium in a Community-Based Sample

BACKGROUND

Water-pipe smoking is increasing in popularity, driven partly by a perception of reduced harm compared with cigarette smoking. This study evaluates the association of water-pipe smoking with coronary artery calcium (CAC), a marker of coronary heart disease (CHD) risk, in a community-based sample.

METHODS

A total of 175 exclusive water-pipe smokers and 170 nonsmokers, ≥ 35 years of age, were recruited from the community in Lebanon and Qatar. Water-pipe smoking was assessed using a validated questionnaire. CAC score was assessed using multidetector CT scan. The association of water-pipe smoking with the presence and extent of CAC was evaluated using regression analyses adjusted for CHD risk factors.

RESULTS

CAC was present in 41% of water-pipe smokers vs 28% of nonsmokers (P = .01), with an average CAC score ± SD of 90.6 ± 400.3 Agatston units (AUs) in water-pipe smokers and 52.4 ± 218.6 AUs in nonsmokers. In adjusted analyses, water-pipe smokers had significantly higher adjusted odds of having CAC (OR = 2.20; 95% CI, 1.20-4.01; P = .01) and being in the high CHD risk category defined by CAC > 300 AUs (OR = 3.41; 95% CI, 1.08-10.77; P = .04) or CAC > 75% of age, sex, and race-predicted (OR = 3.11; 95% CI, 1.55-6.24; P = .001) than nonsmokers. CAC extent was significantly associated with water-pipe smoking extent measured by smoking duration (β = 0.17/year; 95% CI, 0.05-0.29; P = .004) or the product of smoking duration and the number of water pipes smoked daily (β = 0.04/water-pipe-year; 95% CI, 0.003-0.07; P = .03).

CONCLUSIONS

Exclusive water-pipe smoking was associated with the presence and extent of CAC, with twice the risk of having CAC and three times the risk of being in the high CHD risk category while accounting for other risk factors.

Effects of teriparatide on morphology of aortic calcification in aged hyperlipidemic mice

Calcific aortic vasculopathy correlates with bone loss in osteoporosis in an age-independent manner. Prior work suggests that teriparatide, the bone anabolic treatment for postmenopausal osteoporosis, may inhibit the onset of aortic calcification. Whether teriparatide affects the progression of preexisting aortic calcification, widespread among this patient population, is unknown. Female apolipoprotein E-deficient mice were aged for over 1 yr to induce aortic calcification, treated for 4.5 wk with daily injections of control vehicle (PBS), 40 µg/kg teriparatide (PTH40), or 400 µg/kg teriparatide (PTH400), and assayed for aortic calcification by microcomputed tomography (microCT) before and after treatment. In a followup cohort, aged female apolipoprotein E-deficient mice were treated with PBS or PTH400 and assayed for aortic calcification by serial microCT and micropositron emission tomography. In both cohorts, aortic calcification detected by microCT progressed similarly in all groups. Mean aortic ¹⁸F-NaF incorporation, detected by serial micropositron emission tomography, increased in the PBS-treated group (+14 ± 5%). In contrast, ¹⁸F-NaF incorporation decreased in the PTH400-treated group (-33 ± 20%, P = 0.03). Quantitative histochemical analysis by Alizarin red staining revealed a lower mineral surface area index in the PTH400-treated group compared with the PBS-treated group ( P = 0.04). Furthermore, Masson trichrome staining showed a significant increase in collagen deposition in the left ventricular myocardium of mice that received PTH400 [2.1 ± 0.6% vs. control mice (0.5 ± 0.1%), P = 0.02]. In summary, although teriparatide may not affect the calcium mineral content of aortic calcification, it reduces ¹⁸F-NaF uptake in calcified lesions, suggesting the possibility that it may reduce mineral surface area with potential impact on plaque stability. NEW & NOTEWORTHY Parathyroid hormone regulates bone mineralization and may also affect vascular calcification, which is an important issue, given that its active fragment, teriparatide, is widely used for the treatment of osteoporosis. To determine whether teriparatide alters vascular calcification, we imaged aortic calcification in mice treated with teriparatide and control mice. Although teriparatide did not affect the calcium content of cardiovascular deposits, it reduced their fluoride tracer uptake.

Coronary artery calcium may stabilize following islet cell transplantation in patients with type 1 diabetes

Islet cell transplantation can functionally cure type 1 diabetes and also improve carotid intima-media thickness. This study provides a preliminary description of changes in coronary artery calcium following islet transplantation, and associated factors. Coronary artery calcium was measured in 14 patients with type 1 diabetes (11 had measures both pre- and post-transplant [mean 2.3 years]) in the University of Illinois at Chicago's clinical trial. Multivariable mixed-effects linear regression of repeated measures was used to quantify calcium change and determine if this change was longitudinally associated with risk/protective factors. Thirteen of the patients were female, with mean baseline age, diabetes duration, and BMI of 47.6 and 28.7 years, and 23.1, respectively. Over half (57%) had detectable coronary artery calcium pre-transplant. Minimal change (0.39 mm³ /y, P = .02) occurred in coronary artery calcium levels pre- to post-transplant. No patient met criteria for calcium progression. Coronary artery calcium was positively associated with total and small VLDL particles (P ≤ .02), statin dose (P = .02), and urine albumin-to-creatinine ratio (P = .04) and negatively associated with free fatty acids (P = .03), total HDL (P = .03), large HDL particles (P = .005), and tacrolimus dose (P = .02). Islet transplant may stabilize coronary artery calcium, with optimal management of lipids and kidney function remaining key therapeutic targets. [NCT00679041].

Coronary Artery Calcification and Rheumatoid Arthritis: Lack of Relationship to Risk Alleles for Coronary Artery Disease in the General Population

OBJECTIVE

Coronary artery disease (CAD) in the general population is characterized by an increased frequency of particular susceptibility single-nucleotide polymorphisms (SNPs). Because the frequency of CAD is increased among patients with rheumatoid arthritis (RA), we sought to determine whether the frequency of these SNPs is increased in RA patients with CAD, hypothesizing that RA could enhance CAD risk by acting through established genetic pathways predisposing to CAD.

METHODS

Coronary artery calcification (CAC) as detected by computed tomography was used as a measure of CAD in 561 patients with RA. One hundred SNPs associated with CAD in the general population were genotyped or imputed, and their relationship to CAC was established through multiple regression analysis for individual SNPs and a genetic risk score representing their cumulative effect.

RESULTS

Ninety-one CAD-related SNPs were genotyped successfully; of these, 81 exhibited no association with CAC (Agatston units) or different CAC categorizations, either individually or collectively, in the genetic risk score. Only rs579459 (ABO) and rs17676451 (HAL) had a consistent positive association between genotype and CAC, with a significant increase in the frequency of the effect allele in both homozygous and heterozygous genotype distributions. Five were variably negatively associated. Furthermore, a positive association between the Disease Activity Score in 28 joints and CAC was observed, and after adjustment for traditional cardiovascular risk factors, it was not modified by correcting for the CAD-related SNP genetic risk score.

CONCLUSION

The increased risk of CAC in patients with RA does not appear to operate primarily through established genetically regulated atherogenic mechanisms that are preponderant in the general population.

The relationship between coronary artery calcium scores and left atrium size in hemodialysis patients

PURPOSE

Hemodialysis patients have extremely increased cardiovascular mortality. The coronary artery calcification score (CACS) in uremic patients receiving hemodialysis reflects the severity of atherosclerotic vascular disease and predicts the cardiovascular events. In cardiac conditions, left atrial (LA) size has a prognostic importance. In this study, relationship between coronary artery calcification and left atrial size was investigated.

METHODS

This was a cross-sectional study involving 32 hemodialysis patients (16 females, 16 males; mean age, 52.4 ± 14.1 years) receiving HD for ≥6 months. Coronary artery calcium scoring was performed by a 16-MDCT scanner, and CACS was calculated by Agatston score. A calcification was defined as a minimum of two adjacent pixels (>0.52 mm²) with a density over 130 Hounsfield units. Patients were divided into two subgroups (group 1: CACS ≤ 45.85, n = 16 and group 2: CACS > 45.85, n = 16) according to median CACS value.

RESULTS

Mean CACS value of 32 hemodialysis patients was 245.57 ± 373.91. LA size was significantly higher in patients with CACS > 45.85 (group 2) than in patients with CACS ≤ 45.85 (group 1). In the bivariate correlation analysis, total CACS was positively correlated with left atrium size (r = 0.47, p = 0.006). Total CACS was positively correlated with age (r = 0.43, p = 0.014). LA size was positively correlated with diastolic blood pressure (r = 0.42, p = 0.016) and negatively correlated with ejection fraction (r = -0.42, p = 0.016). The clinical parameters such as BMI, duration of dialysis, blood pressure, ejection fraction, serum levels of calcium, phosphorus, uric acid, albumin, CRP, triglyceride, cholesterol, hemoglobin and ferritin were not independently associated with total CACS.

CONCLUSIONS

We found a positive relationship between the CACS and LA size measured by echocardiography in hemodialysis patients. Therefore; echocardiography, which is cheaper and non-invasive than tomographic examinations, might be considered for the risk stratification of coronary artery disease in hemodialysis patients.

Renal function had an independent relationship with coronary artery calcification in Chinese elderly men

BACKGROUND

Although previous studies have analyzed the relationship between renal function and coronary artery calcification (CAC) in pre-dialysis and dialysis patients, limited studies have discussed the relationship between renal function and CAC in Chinese elderly men without obvious damage of renal function. The present study was designed to explore the relationship between renal function and CAC in Chinese elderly men without obvious damage of renal function.

METHODS

This cross-sectional study was carried out in 105 male participants older than 60 years with glomerular filtration rate (GFR) ≥ 45 ml/min/1.73 m². CAC was detected by high-definition computerized tomography (HDCT), which is a highly sensitive technique for detecting the CAC and provides the most accurate CAC scores up to date.

RESULTS

Age was 72 ± 8.4 years on average and ranged from 60 to 89 years. Simple correlation analysis indicated that all kinds of CAC scores including the Agatston, volume and mass scores inversely correlated with GFR values (p < 0.05 for all). In multivariate linear regression analysis, GFR values were independently associated with all these CAC scores (p < 0.05 for all).

CONCLUSION

Renal function had an independent relationship with CAC detected by HDCT in Chinese elderly men, demonstrating that the relationship between renal function and CAC started at the early stage of renal function decline.

Diagnostic accuracy of carotid intima media thickness in predicting coronary plaque burden on coronary computed tomography angiography in patients with obstructive sleep apnoea

AIM

To assess the diagnostic accuracy of common carotid artery intima media thickness (CIMT) for coronary artery disease (CAD) detection in patients with obstructive sleep apnoea (OSA).

MATERIALS & METHODS

Patients with clinically suspected OSA prospectively underwent polysomnography (PSG), ultrasound CIMT measurement and coronary computed tomography angiography (CTA). An average CIMT of ≥0.9 mm in either common carotid artery designated as a positive test. Coronary CTA was the reference standard for the presence of CAD. Coronary plaque presence, volume, density and type were correlated with CIMT findings.

RESULTS

35 consecutive male patients were enrolled from sleep clinic. Two patients had no evidence of OSA on PSG (apnoea-hypopnea index [AHI]<5/hr), and were excluded. Of the remaining 33, 18 (54%) had mild-moderate OSA (AHI 5-30/hr) and 15 (46%) had severe OSA (AHI >30/hr). Eight (24%) patients had CAD on coronary CTA. Coronary plaques were predominantly non- or partly calcified, and located in proximal coronary artery segments. Sensitivity, specificity, positive and negative predictive and likelihood ratios for a positive CIMT (≥0.9 mm) in diagnosing CAD were 0.5 (95% confidence interval: 0.76-0.12), 0.96 (1-0.89), 80, 85.7, 12.5 and 0.52 respectively. The adjusted odds ratio was 40.8.

CONCLUSION

In patients with OSA, CIMT is a highly specific but poorly sensitive test for detecting CAD.

Subclinical coronary atherosclerosis is more pronounced in men and women with lower socio-economic status: associations in a population-based study Coronary atherosclerosis and social status

Background

Social inequalities of manifest coronary heart diseases are well documented in modern societies. Less evidence is available on subclinical atherosclerotic disease despite the opportunity to investigate processes underlying this association. Therefore, we examined the relationship between coronary artery calcification as a sign of subclinical coronary atherosclerosis, socio-economic status and established cardiovascular risk factors in a healthy population.

Design

Cross-sectional.

Methods

In a population-based sample of 4487 men and women coronary artery calcification was assessed by electron beam computed tomography quantified by the Agatston score. Socio-economic status was assessed by two indicators, education and income. First, we investigated associations between the social measures and calcification. Second, we assessed the influence of cardiovascular risk factors on this association.

Results

After adjustment for age, men with 10 and less years of formal education had a 70% increase in calcification score compared with men with high education. The respective increase for women was 80%. For income the association was weaker (among men 20% higher for the lowest compared with the highest quartile; and among women 50% higher, respectively). Consecutive adjustment for cardiovascular risk factors significantly attenuated the observed association of socio-economic status with calcification.

Conclusions

Social inequalities in coronary heart diseases seem to influence signs of subclinical coronary atherosclerosis as measured by coronary artery calcification. Importantly, cumulation of major cardiovascular risk factors in lower socio-economic groups accounted for a substantial part of this association.

Inflammation Drives Retraction, Stiffening, and Nodule Formation via Cytoskeletal Machinery in a Three-Dimensional Culture Model of Aortic Stenosis

In calcific aortic valve disease, the valve cusps undergo retraction, stiffening, and nodular calcification. The inflammatory cytokine, tumor necrosis factor (TNF)-α, contributes to valve disease progression; however, the mechanisms of its actions on cusp retraction and stiffening are unclear. We investigated effects of TNF-α on murine aortic valvular interstitial cells (VICs) within three-dimensional, free-floating, compliant, collagen hydrogels, simulating their natural substrate and biomechanics. TNF-α increased retraction (percentage of diameter), stiffness, and formation of macroscopic, nodular structures with calcification in the VIC-laden hydrogels. The effects of TNF-α were attenuated by blebbistatin inhibition of myosin II-mediated cytoskeletal contraction. Inhibition of actin polymerization with cytochalasin-D, but not inhibition of Rho kinase with Y27632, blocked TNF-α-induced retraction in three-dimensional VIC hydrogels, suggesting that actin stress fibers mediate TNF-α-induced effects. In the hydrogels, inhibitors of NF-κB blocked TNF-α-induced retraction, whereas simultaneous inhibition of c-Jun N-terminal kinase was required to block TNF-α-induced stiffness. TNF-α also significantly increased collagen deposition, as visualized by Masson's trichrome staining, and up-regulated mRNA expression of discoidin domain receptor tyrosine kinase 2, fibronectin, and α-smooth muscle actin. In human aortic valves, calcified cusps were stiffer and had more collagen deposition than noncalcified cusps. These findings suggest that inflammation, through stimulation of cytoskeletal contractile activity, may be responsible for valvular cusp retraction, stiffening, and formation of calcified nodules.

Pathogenesis of Varicose Veins and Implications for Clinical Management

Varicose veins (VVs) classically result from venous hypertension owing to incompetence of the major communications between the superficial and deep veins of the lower extremity. In a significant number of patients, there is no demonstrable truncal saphenous reflux and varicosities are the result of isolated perforating and nonsaphenous vein incompetence. The clinical and histologic features of VVs are the result of disruption of the normal architectural structure of the venous wall as a consequence of remodeling of the extracellular matrix (ECM) in response to increased venous distention and altered hemodynamic shear stress. Although a number of genes, growth factors, proteases, and their inhibitors known to modulate the ECM have been implicated in the pathogenesis of VVs, their etiology remains unknown. The complex variations in venous anatomy in patients with VVs require detailed vein mapping to determine the source and drainage locations of reflux if the rates of residual and recurrent varicosities are to be reduced. The distinct pathogenic mechanisms involved in the development of VVs have important implications for the management of VVs that include a wide spectrum of treatment modalities ranging from reassurance, alternative medicines, conservative management or compression therapy, and surgical or endovascular therapy.

Protective Role of Smad6 in Inflammation-Induced Valvular Cell Calcification

Calcific aortic vascular and valvular disease (CAVD) is associated with hyperlipidemia, the effects of which occur through chronic inflammation. Evidence suggests that inhibitory small mothers against decapentaplegic (I-Smads; Smad6 and 7) regulate valve embryogenesis and may serve as a mitigating factor in CAVD. However, whether I-Smads regulate inflammation-induced calcific vasculopathy is not clear. Therefore, we investigated the role of I-Smads in atherosclerotic calcification. Results showed that expression of Smad6, but not Smad7, was reduced in aortic and valve tissues of hyperlipidemic compared with normolipemic mice, while expression of tumor necrosis factor alpha (TNF-α) was upregulated. To test whether the effects are in response to inflammatory cytokines, we isolated murine aortic valve leaflets and cultured valvular interstitial cells (mVIC) from the normolipemic mice. By immunochemistry, mVICs were strongly positive for vimentin, weakly positive for smooth muscle α actin, and negative for an endothelial cell marker. TNF-α upregulated alkaline phosphatase (ALP) activity and matrix mineralization in mVICs. By gene expression analysis, TNF-α significantly upregulated bone morphogenetic protein 2 (BMP-2) expression while downregulating Smad6 expression. Smad7 expression was not significantly affected. To further test the role of Smad6 on TNF-α-induced valvular cell calcification, we knocked down Smad6 expression using lentiviral transfection. In cells transfected with Smad6 shRNA, TNF-α further augmented ALP activity, expression of BMP-2, Wnt- and redox-regulated genes, and matrix mineralization compared with the control cells. These findings suggest that TNF-α induces valvular and vascular cell calcification, in part, by specifically reducing the expression of a BMP-2 signaling inhibitor, Smad6.

Coronary computed tomography angiography and calcium scoring in routine clinical practice for identification of patients who require revascularization

BACKGROUND

The predictive value of CCTA to predict coronary artery disease is high in particular in the absence of coronary calcification. However, the consideration of both CCTA and the calcium score, in addition to the risk factors to determine the indication for coronary revascularization, has not been yet studied.

MATERIALS AND METHODS

This study included 2302 patients (mean age: 60±9.8 years, 46% men), without known coronary artery disease (CAD), who underwent 320-row CCTA. Logistic regression, c-statistic and net reclassification improvement (NRI) were used to assess the role of coronary artery calcium score (CACS) in predicting revascularization after CCTA.

RESULTS

The revascularization rates were 0.75% in patients with a CACS of 0, and there were no adverse events during the follow-up period. The revascularization rates were 3.3% in patients with a CACS of 1-99, 15.4% in patients with a CACS of 100-399, 25.6% in patients with a CACS of 400-999, and 42.4% in patients with a CACS≥1000. The crude and adjusted odds ratios (95% confidence interval) for revascularization per CACS group category were 2.89 (2.53-2.3) and 2.71 (2.33-3.15), respectively; the area under the ROC curve (AUC) was 0.85 (0.83-0.88). The addition of CACS to conventional risk factors improved the accuracy of risk prediction model for revascularization (AUC 0.74 vs 0.63, P=0.001), but it did not reclassify a substantial proportion of patients with positive CACS to risk categories (NRI=-0.023, P=0.66).

CONCLUSIONS

The 320-row CCTA might rule out CAD in low- to intermediate-risk patients. However, its accuracy in identifying patients who require revascularization is limited. The CACS added to the conventional risk factors did not improve the identification of patients who require revascularization.

Intracranial Artery Calcification and Its Clinical Significance

Intracranial arterial calcification (IAC) is an easily identifiable entity on plain head computed tomography scans. Recent studies have found high prevalence rates for IAC worldwide, and this may be associated with ischemic stroke and cognitive decline. Aging, traditional cardiovascular risk factors, and chronic kidney disease have been found to be associated with IAC. The severity of IAC can be assessed using different visual grading scales or various quantitative methods (by measuring volume or intensity). An objective method for assessing IAC using consistent criteria is urgently required to facilitate comparisons between multiple studies involving diverse populations. There is accumulating evidence from clinical studies that IAC could be utilized as an indicator of intracranial atherosclerosis. However, the pathophysiology underlying the potential correlation between IAC and ischemic stroke-through direct arterial stenosis or plaque stability-remains to be determined. More well-designed clinical studies are needed to explore the predictive values of IAC in vascular events and the underlying pathophysiological mechanisms.

Bone Like Arterial Calcification in Femoral Atherosclerotic Lesions: Prevalence and Role of Osteoprotegerin and Pericytes

OBJECTIVE/BACKGROUND

Arterial calcification, a process that mimics bone formation, is an independent risk factor of cardiovascular morbidity and mortality, and has a significant impact on surgical and endovascular procedures and outcomes. Research efforts have focused mainly on the coronary arteries, while data regarding the femoral territory remain scarce.

METHODS

Femoral endarterectomy specimens, clinical data, and plasma from a cohort of patients were collected prospectively. Histological analysis was performed to characterize the cellular populations present in the atherosclerotic lesions, and that were potentially involved in the formation of bone like arterial calcification known as osteoid metaplasia (OM). Enzyme linked immunosorbent assays and cell culture assays were conducted in order to understand the cellular and molecular mechanisms underlying the formation of OM in the lesions.

RESULTS

Twenty-eight of the 43 femoral plaques (65%) displayed OM. OM included osteoblast and osteoclast like cells, but very few of the latter exhibited the functional ability to resorb mineral tissue. As in bone, osteoprotegerin (OPG) was significantly associated with the presence of OM (p = .04). Likewise, a high plasma OPG/receptor activator for the nuclear factor kappa B ligand (RANKL) ratio was significantly associated with the presence of OM (p = .03). At the cellular level, there was a greater presence of pericytes in OM+ compared with OM- lesions (5.59 ± 1.09 vs. 2.42 ± 0.58, percentage of area staining [region of interest]; p = .04); in vitro, pericytes were able to inhibit the osteoblastic differentiation of human mesenchymal stem cells, suggesting that they are involved in regulating arterial calcification.

CONCLUSION

These results suggest that bone like arterial calcification (OM) is highly prevalent at femoral level. Pericyte cells and the OPG/RANK/RANKL triad seem to be critical to the formation of this ectopic osteoid tissue and represent interesting potential therapeutic targets to reduce the clinical impact of arterial calcification.

Association between brachial-ankle pulse wave velocity and progression of coronary artery calcium: a prospective cohort study

BACKGROUND

Few studies have investigated the association between coronary artery calcium (CAC) progression and arterial stiffness measured by brachial-ankle pulse wave velocity (baPWV). We examined the influence of the severity of baseline baPWV on CAC progression in a large prospective cohort.

METHODS

A total of 1600 subjects who voluntarily participated in a comprehensive health-screening program between March 2010 and December 2013 and had baseline baPWV as well as CAC on baseline and serial follow-up computed tomography performed approximately 2.7 ± 0.5 years apart were enrolled in the study.

RESULTS

A total of 1124 subjects were included in the analysis (1067 men; mean age, 43.6 ± 5.1 years). An increased CAC score was found in 318 subjects (28.3%) during the follow-up period. Baseline higher baPWV was significantly correlated with CAC progression, especially in subjects with third- and fourth-quartile values (adjusted odds ratio [OR] 2.04; 95% confidence interval [CI] 1.33-3.15 and OR 2.14; 95% CI 1.34-3.41, respectively) compared with the lowest-quartile values (P for trend <0.001). A similar effect was observed in diabetic subjects. Among the 835 subjects with a baseline CAC score = 0, progression to CAC score >0 was associated with male sex, diabetes, and higher baPWV. However, among the 289 individuals with a baseline CAC score >0, only the presence of CAC itself was predictive of CAC progression.

CONCLUSIONS

Higher arterial stiffness measured by baPWV could be significantly associated with CAC progression.

Coronary artery calcium: 0.5 mm slice-thickness reconstruction with adjusted attenuation threshold outperforms 3.0 mm by validating against spatially registered intravascular ultrasound with radiofrequency backscatter

RATIONALE AND OBJECTIVES

Coronary artery calcium (CAC) images can be reconstructed with thinner slice thickness on some modern multidetector-row computed tomography scanners without additional radiation. We hypothesized that the isotropic 0.5-mm CAC reconstruction outperforms the conventional 3.0-mm reconstruction in detecting and quantifying coronary calcium, and we proposed to compare them by validating against spatially registered intravascular ultrasound with radiofrequency backscatter-virtual histology (IVUS-VH).

MATERIALS AND METHODS

Twenty-seven patients were enrolled, and 5976 mm of coronary arteries were analyzed. A semiautomatic software was developed to coregister CAC and IVUS-VH on a detailed slice-by-slice basis. Calcium detection and calcium volume quantification were evaluated and compared using varying calcium attenuation thresholds. Algorithms for deriving individualized optimal threshold and comparable Agatston score on the 0.5-mm reconstruction were developed.

RESULTS

The isotropic 0.5-mm reconstruction achieved significantly higher area under receiver-operating curve than the conventional 3.0-mm reconstruction (0.9 vs. 0.74, P < .001). Using the optimal threshold, the 0.5-mm reconstruction had higher sensitivity (0.79 vs. 0.65), specificity (0.85 vs. 0.77), positive predictive value (0.42 vs. 0.29), and negative predictive value (0.97 vs. 0.94) than the 3.0 mm. Individualized optimal threshold was significantly correlated with the image noise (r = 0.66, P < .001) in the 0.5-mm reconstruction.

CONCLUSIONS

By optimizing the calcium threshold, the 0.5-mm reconstruction is superior to the conventional 3.0-mm in detecting and quantifying calcium, which may improve the clinical value of CAC without additional radiation.

The role of septal perforators and "myocardial bridging effect" in atherosclerotic plaque distribution in the coronary artery disease

The distribution of atherosclerotic plaque burden in the human coronary arteries is not uniform. Plaques are located mostly in the left anterior descending artery (LAD), then in the right coronary artery (RCA), circumflex branch (LCx) and the left main coronary artery (LM) in a decreasing order of frequency. In the LAD and LCx, plaques tend to cluster within the proximal segment, while in the RCA their distribution is more uniform. Several factors have been involved in this phenomenon, particularly flow patterns in the left and right coronary artery. Nevertheless, it does not explain the difference in lesion frequency between the LAD and the LCx as these are both parts of the left coronary artery. Branching points are considered to be the risk points of atherosclerosis. In the LCx, the number of side branches is lower than in the LAD or RCA and there are no septal perforators with intramuscular courses like in the proximal third of the LAD and the posterior descending artery (PDA). We hypothesized that septal branches generate disturbed flow in the LAD and PDA in a similar fashion to the myocardial bridge (myocardial bridging effect). This coronary architecture determines the non-uniform plaque distribution in coronary arteries and LAD predisposition to plaque formation.

Cardiac imaging in patients with chronic kidney disease

Patients with chronic kidney disease (CKD) carry a high cardiovascular risk. In this patient group, cardiac structure and function are frequently abnormal and 74% of patients with CKD stage 5 have left ventricular hypertrophy (LVH) at the initiation of renal replacement therapy. Cardiac changes, such as LVH and impaired left ventricular systolic function, have been associated with an unfavourable prognosis. Despite the prevalence of underlying cardiac abnormalities, symptoms may not manifest in many patients. Fortunately, a range of available and emerging cardiac imaging tools may assist with diagnosing and stratifying the risk and severity of heart disease in patients with CKD. Moreover, many of these techniques provide a better understanding of the pathophysiology of cardiac abnormalities in patients with renal disease. Knowledge of the currently available cardiac imaging modalities might help nephrologists to choose the most appropriate investigative tool based on individual patient circumstances. This Review describes established and emerging cardiac imaging modalities in this context, and compares their use in CKD patients with their use in the general population.

Screening for asymptomatic coronary heart disease in the young 'at risk' population: Who and how?

Deaths due to coronary heart disease (CHD) remain high worldwide, despite recent achievements. An effective screening strategy may improve outcomes further if implemented in a high or ‘at risk’ cohort. Asymptomatic CHD in the young maybe underappreciated and applying an effective screening strategy to a young cohort may lead to improved outcomes due to significant socioeconomic impact from the consequences of CHD in this sub-group. A positive family history of CHD, which is known to be associated with an increased risk of future myocardial events, could aid in identifying the ‘at risk’ young cohort.

Traditional cardiovascular risk scoring systems are in wide use but lack the sensitivity or specificity required to estimate risk in an individual. Rather their use is limited to predicting population attributable risk. Functional studies such as exercise stress tests are readily available and cost effective but do not have the required sensitivity required to suggest their use as part of a screening protocol. Coronary CT angiography has been demonstrated to have high sensitivity for the detection of CHD and therefore may be suitable for screening purposes but there are concerns regarding radiation exposure.

Here we review the evidence for the use of potential screening strategies and the suitability of using such strategies to estimate risk of CHD in a young ‘at risk’ population.

Vascular health late after Kawasaki disease: implications for accelerated atherosclerosis

Kawasaki disease (KD), an acute vasculitis that primarily affects young children, is the most common acquired paediatric cardiovascular disease in developed countries. While sequelae of arterial inflammation in the acute phase of KD are well documented, its late effects on vascular health are increasingly unveiled. Late vascular dysfunction is characterized by structural alterations and functional impairment in term of arterial stiffening and endothelial dysfunction and shown to involve both coronary and systemic arteries. Further evidence suggests that continuous low grade inflammation and ongoing active remodeling of coronary arterial lesions occur late after acute illness and may play a role in structural and functional alterations of the arteries. Potential importance of genetic modulation on vascular health late after KD is implicated by associations between mannose binding lectin and inflammatory gene polymorphisms with severity of peripheral arterial stiffening and carotid intima-media thickening. The changes in cholesterol and lipoproteins levels late after KD further appear similar to those proposed to be atherogenic. While data on adverse vascular health are less controversial in patients with persistent or regressed coronary arterial aneurysms, data appear conflicting in individuals with no coronary arterial involvements or only transient coronary ectasia. Notwithstanding, concerns have been raised with regard to predisposition of KD in childhood to accelerated atherosclerosis in adulthood. Until further evidence-based data are available, however, it remains important to assess and monitor cardiovascular risk factors and to promote cardiovascular health in children with a history of KD in the long term.

Obstructive sleep apnea and progression of coronary artery calcium: the multi-ethnic study of atherosclerosis study

Background

Obstructive sleep apnea (OSA) is a common condition associated with cardiovascular disease. Its potential effect on progression of subclinical atherosclerosis is not well understood. We tested the hypothesis that self‐reported OSA is associated with progression of coronary artery calcium (CAC). We also evaluated whether traditional cardiovascular risk factors accounted for the association.

Methods and Results

In the Multi‐Ethnic Study of Atherosclerosis (MESA) prospective cohort, we studied 2603 participants who at baseline (2002–2004) completed a sleep questionnaire and underwent coronary computed tomography (CT) and, then 8 years later (2010–2011), a repeat coronary CT. Participants were categorized by symptoms of habitual snoring or reported physician diagnosis of OSA. At baseline, 102 (3.9%) reported diagnosed OSA; 666 (25.6%) reported diagnosed habitual snoring; and 1835 (70.5%) reported neither habitual snoring nor OSA (“normal”). At baseline, CAC prevalence was highest among those with OSA but similar for those with and without habitual snoring. During 8 years of follow‐up, greater progression of CAC was observed among those with OSA versus normal (mean increase of 204.2 versus 135.5 Agatston units; P=0.01), after accounting for demographics, behaviors, and body habitus. Modest attenuation was observed after adjustment for cardiovascular risk factors (188.7 versus 138.8; P=0.06). CAC progression among habitual snorers was similar to that observed in the normal group.

Conclusions

OSA was associated with CAC score progression after adjustment for demographics, behaviors, and body mass index. However, the association was not significant after accounting for cardiovascular risk factors, which may mediate the association between OSA and CAC.

The relationship between diastolic blood pressure and coronary artery calcification is dependent on single nucleotide polymorphisms on chromosome 9p21.3

Background

Single nucleotide polymorphisms (SNPs) within the 9p21.3 genomic region have been consistently associated with coronary heart disease (CHD), myocardial infarction, and quantity of coronary artery calcification (CAC), a marker of subclinical atherosclerosis. Prior studies have established an association between blood pressure measures and CAC. To examine mechanisms by which the 9p21.3 genomic region may influence CHD risk, we investigated whether SNPs in 9p21.3 modified associations between blood pressure and CAC quantity.

Methods

As part of the Genetic Epidemiology Network of Arteriopathy (GENOA) Study, 974 participants underwent non-invasive computed tomography (CT) to measure CAC quantity. Linear mixed effects models were used to investigate whether seven SNPs in the 9p21.3 region modified the association between blood pressure levels and CAC quantity. Four SNPs of at least marginal significance in GENOA for a SNP-by-diastolic blood pressure (DBP) interaction were then tested for replication in the Framingham Heart Study’s Offspring Cohort (N = 1,140).

Results

We found replicated evidence that one SNP, rs2069416, in CDKN2B-AS1, significantly modified the association between DBP and CAC quantity (combined P = 0.0065; Bonferroni-corrected combined P = 0.0455).

Conclusions

Our results represent a novel finding that the relationship between DBP and CAC is dependent on genetic variation in the 9p21.3 region. Thus, variation in 9p21.3 may not only be an independent genetic risk factor for CHD, but also may modify the association between DBP levels and the extent of subclinical coronary atherosclerosis.

The effects of coronary artery calcium screening on behavioral modification, risk perception, and medication adherence among asymptomatic adults: a systematic review

OBJECTIVE

To perform systematic review of the effects of screening for coronary artery calcium (CAC), a subclinical marker of coronary artery disease (CAD), on behavioral or lifestyle modification, risk perception, and medication adherence.

METHODS

We searched through CINAHL, PsychInfo, Web of Science, Cochrane Central Register of Control Trials, and PubMed (Medline) for studies on the effects of CAC screening in asymptomatic individuals across three major domains: behavioral modification, risk perception for CAD, and medication adherence. We extracted data from the retrieved studies, assessed and synthesized the information.

RESULTS

Of the 15 retrieved studies, three were randomized control trials and 12 were observational studies. CAC score was ascertained either as total score, quartiles, or standardized Agatston's ordinal scale. While all the 15 studies involved issues related to behavioral and medication adherence, four involved risk perception of CAD. Although no standardized approach was used in these studies, CAC screening enhanced medication adherence in 13 of the 15 studies, while the others were mixed.

CONCLUSION

CAC screening improved medication adherence and could likely motivated individuals for beneficial behavioral or lifestyle changes to improve CAD. The mixed results suggest the need for further research because screening for subclinical atherosclerosis has significant implications for early detection and prevention of future cardiovascular events by aggressive risk factors modification.

Risks and diagnosis of coronary artery disease in Hodgkin lymphoma survivors

Higher mortality rates are reported because of cardiovascular diseases in individuals living in industrialized areas of the World. In cancer patients, cardiotoxic chemotherapeutic agents and/or mediastinal radiotherapy are additional risk factors for the development of coronary artery disease. An improved survival rate for patients with Hodgkin lymphoma was reported in recent decades. Determining and handling the long-term effects of cancer treatment have become more important nowadays, parallel to the good results reached in survival rates. Mediastinal radiotherapy and cardiotoxic chemotherapeutic agents are routinely used to treat Hodgkin lymphoma but are commonly associated with a variety of cardiovascular complications. Drugs used in cancer treatment and radiotherapy may cause deleterious effects on contractile capacity and conduction system of the heart. Approximately ten years after the completion of all therapies, the cardiovascular disease risk peaks in patients who survived from Hodgkin lymphoma. The value of coronary computed tomography angiography as a diagnostic tool in determining coronary artery disease as early as possible is underlined in this review, in patients who are in remission and carry the risk of coronary artery disease probably because of chemo/radiotherapy used in their treatment. Survivors of Hodgkin lymphoma especially treated with combined chemoradiotherapy at younger ages are candidates for coronary computed tomography angiography.

Multidetector-row computed tomography for noninvasive coronary imaging

Computed tomography (CT) permits cross-sectional imaging of the heart. Temporal and spatial resolutions of the technique have been insufficient to cover the heart without motion artefacts until the recent advent of multidetector systems with more than 16 detector rows. The modality is now suited for noninvasive imaging of the coronary arteries, producing detailed morphologic images of the entire coronary tree with upto 0.4 mm of spatial resolution, within a single short breath-hold duration. CT imaging goes beyond the delineation of the coronary lumen as provided by selective invasive angiography; the plaque burden of the coronary artery wall can be visualized directly, utilizing soft-tissue contrast and a high sensitivity even for the small calcifications that are present in hard plaque formations. Therefore, CT combines elements of catheterization angiography for lumen imaging and of intravascular ultrasound imaging for coronary wall imaging. However current CT technology is not yet able to compete with the temporal or spatial resolution of catheterization angiography nor does it provide the detailed spatial or contrast resolution of intravascular ultrasound imaging. At present, its use is therefore restricted to complementing the invasive modalities in appropriate indications. Although CT entails significantly less risk than the invasive procedures, the risks of radiation dose exposure and contrast agent application are not negligible. In the foreseeable future, if the current rate of technological advancement continues, CT may replace the invasive modalities in routine care for diagnostic purposes.

Osteoprotegerin inhibits calcification of vascular smooth muscle cell via down regulation of the Notch1-RBP-Jκ/Msx2 signaling pathway

Objective

Vascular calcification is a common pathobiological process which occurs among the elder population and in patients with diabetes and chronic kidney disease. Osteoprotegerin, a secreted glycoprotein that regulates bone mass, has recently emerged as an important regulator of the development of vascular calcification. However, the mechanism is not fully understood. The purpose of this study is to explore novel signaling mechanisms of osteoprotegerin in the osteoblastic differentiation in rat aortic vascular smooth muscle cells (VSMCs).

Methods and Results

VSMCs were isolated from thoracic aorta of Sprague Dawley rats. Osteoblastic differentiation of VSMCs was induced by an osteogenic medium. We confirmed by Von Kossa staining and direct cellular calcium measurement that mineralization was significantly increased in VSMCs cultured in osteogenic medium; consistent with an enhanced alkaline phosphatase activity. This osteoblastic differentiation in VSMCs was significantly reduced by the addition of osteoprotegerin in a dose responsive manner. Moreover, we identified, by real-time qPCR and western blotting, that expression of Notch1 and RBP-Jκ were significantly up-regulated in VSMCs cultured in osteogenic medium at both the mRNA and protein levels, these effects were dose-dependently abolished by the treatment of osteoprotegerin. Furthermore, we identified that Msx2, a downstream target of the Notch1/RBP-Jκ signaling, was markedly down-regulated by the treatment of osteoprotegerin.

Conclusion

Osteoprotegerin inhibits vascular calcification through the down regulation of the Notch1-RBP-Jκ signaling pathway.