Anouk L. M. Eikendal

Common Carotid Intima-Media Thickness Relates to Cardiovascular Events in Adults Aged <45 Years

Although atherosclerosis starts in early life, evidence on risk factors and atherosclerosis in individuals aged <45 years is scarce. Therefore, we studied the relationship between risk factors, common carotid intima-media thickness (CIMT), and first-time cardiovascular events in adults aged <45 years. Our study population consisted of 3067 adults aged <45 years free from symptomatic cardiovascular disease at baseline, derived from 6 cohorts that are part of the USE-IMT initiative, an individual participant data meta-analysis of general-population–based cohort studies evaluating CIMT measurements. Information on risk factors, CIMT measurements, and follow-up of the combined end point (first-time myocardial infarction or stroke) was obtained. We assessed the relationship between risk factors and CIMT and the relationship between CIMT and first-time myocardial infarction or stroke using a multivariable linear mixed-effects model and a Cox proportional-hazards model, respectively. During a follow-up of 16.3 years, 55 first-time myocardial infarctions or strokes occurred. Median CIMT was 0.63 mm. Of the risk factors under study, age, sex, diastolic blood pressure, body mass index, total cholesterol, and high-density lipoprotein cholesterol related to CIMT. Furthermore, CIMT related to first-time myocardial infarction or stroke with a hazard ratio of 1.40 per SD increase in CIMT, independent of risk factors (95% confidence interval, 1.11–1.76). CIMT may be a valuable marker for cardiovascular risk in adults aged <45 years who are not yet eligible for standard cardiovascular risk screening. This is especially relevant in those with an increased, unfavorable risk factor burden.

Reliability and agreement of adipose tissue fat fraction measurements with water–fat MRI in patients with manifest cardiovascular disease

The supraclavicular fat depot is known for brown adipose tissue presence. To unravel adipose tissue physiology and metabolism, high quality and reproducible imaging is required. In this study we quantified the reliability and agreement of MRI fat fraction measurements in supraclavicular and subcutaneous adipose tissue of 25 adult patients with clinically manifest cardiovascular disease. MRI fat fraction measurements were made under ambient temperature conditions using a vendor supplied mDixon chemical‐shift water–fat multi‐echo pulse sequence at 1.5 T field strength. Supraclavicular fat fraction reliability (intraclass correlation coefficientagreement, ICCagreement) was 0.97 for test–retest, 0.95 for intra‐observer and 0.56 for inter‐observer measurements, which increased to 0.88 when ICCconsistency was estimated. Supraclavicular fat fraction agreement displayed mean differences of 0.5% (limit of agreement (LoA) −1.7 to 2.6) for test–retest, −0.5% (LoA −2.9 to 2.0) for intra‐observer and 5.6% (LoA 0.4 to 10.8) for inter‐observer measurements. Median fat fraction in supraclavicular adipose tissue was 82.5% (interquartile range (IQR) 78.6–84.0) and 89.7% (IQR 87.2–91.5) in subcutaneous adipose tissue (p < 0.0001). In conclusion, water–fat MRI has good reliability and agreement to measure adipose tissue fat fraction in patients with manifest cardiovascular disease. These findings enable research on determinants of fat fraction and enable longitudinal monitoring of fat fraction within adipose tissue depots. Interestingly, even in adult patients with manifest cardiovascular disease, supraclavicular adipose tissue has a lower fat fraction compared with subcutaneous adipose tissue, suggestive of distinct morphologic characteristics, such as brown adipose tissue. Copyright

Fast 3D isotropic imaging of the aortic vessel wall by application of 2D spatially selective excitation and a new way of inversion recovery for black blood imaging

Aortic vessel wall imaging requires large coverage and a high spatial resolution, which makes it prohibitively time‐consuming for clinical use. This work explores the feasibility of imaging the descending aorta in acceptable scan time, using two‐dimensional (2D) spatially selective excitation and a new way of inversion recovery for black blood imaging.

Single Breath-Hold T1ρ-Mapping of the Heart for Endogenous Assessment of Myocardial Fibrosis

ObjectivesIn this study, we propose a method to acquire high spatial-resolution T1&rgr;-maps, which allows bright and black-blood imaging, in a single breath-hold. To validate this innovative method, the reproducibility was tested in phantoms and volunteers. Lastly, the sensitivity and specificity for infarct detection was compared with the criterion standard late gadolinium enhancement (LGE). MethodsT1&rgr;-mapping was performed using a T1&rgr;-prepared balanced steady-state free precession sequence at 1.5 T and 3 T. Five images with increasing spin-lock preparation times (spin-lock = 0, 10, 20, 30, 40 milliseconds, amplitude = 500 Hz) were acquired with an interval of 3 beats. Black-blood imaging was performed using a double inversion pulse sequence. The method was tested in 2 times 10 healthy volunteers at 1.5 and 3 T and in 9 myocardial infarction patients at 1.5 T. T1&rgr;-maps, and LGE images were scored for presence and extent of myocardial scarring. ResultsPhantom results show that the proposed T1&rgr;-mapping method gives accurate T1&rgr;-values. The mean T1&rgr;-relaxation time of the myocardium in healthy controls was 52.8 ± 1.8 milliseconds at 1.5 T and 46.4 ± 1.8 milliseconds at 3 T. In patients, the T1&rgr; of infarcted myocardium was (82.4 ± 5.2 milliseconds), and the T1&rgr; of remote myocardium was (54.2 ± 2.8 milliseconds; P < 0.0001). Sensitivity of infarct detection on a T1&rgr;-map was 70%, with a specificity of 94%, compared with LGE. ConclusionsIn this study, we have investigated a method to acquire high spatial-resolution T1&rgr;-maps of the heart in a single breath-hold. This method proved to be reproducible and had high specificity compared with LGE and can thus be used for the endogenous detection of myocardial fibrosis in patients with ischemic cardiomyopathy.

Reference Values for Cardiac and Aortic Magnetic Resonance Imaging in Healthy, Young Caucasian Adults

Background Reference values for morphological and functional parameters of the cardiovascular system in early life are relevant since they may help to identify young adults who fall outside the physiological range of arterial and cardiac ageing. This study provides age and sex specific reference values for aortic wall characteristics, cardiac function parameters and aortic pulse wave velocity (PWV) in a population-based sample of healthy, young adults using magnetic resonance (MR) imaging. Materials and Methods In 131 randomly selected healthy, young adults aged between 25 and 35 years (mean age 31.8 years, 63 men) of the general-population based Atherosclerosis-Monitoring-and-Biomarker-measurements-In-The-YOuNg (AMBITYON) study, descending thoracic aortic dimensions and wall thickness, thoracic aortic PWV and cardiac function parameters were measured using a 3.0T MR-system. Age and sex specific reference values were generated using dedicated software. Differences in reference values between two age groups (25–30 and 30–35 years) and both sexes were tested. Results Aortic diameters and areas were higher in the older age group (all p<0.007). Moreover, aortic dimensions, left ventricular mass, left and right ventricular volumes and cardiac output were lower in women than in men (all p<0.001). For mean and maximum aortic wall thickness, left and right ejection fraction and aortic PWV we did not observe a significant age or sex effect. Conclusion This study provides age and sex specific reference values for cardiovascular MR parameters in healthy, young Caucasian adults. These may aid in MR guided pre-clinical identification of young adults who fall outside the physiological range of arterial and cardiac ageing.

Relation Between Adolescent Cardiovascular Risk Factors and Carotid Intima-Media Echogenicity in Healthy Young Adults: The Atherosclerosis Risk in Young Adults (ARYA) Study.

Background Echogenicity is an ultrasound measure that reflects arterial wall composition. In adult populations, lower carotid intima‐media echogenicity relates to an unfavorable cardiovascular risk burden yet appears to reflect a different aspect of arterial wall remodeling than carotid intima‐media thickness (CIMT). Since studies on carotid intima‐media echogenicity earlier in life are lacking, we investigated associations between adolescent cardiovascular risk factors and young adulthood carotid intima‐media echogenicity and compared this to CIMT. Methods and Results In 736 participants of the Atherosclerosis Risk in Young Adults study, information on adolescent anthropometrics, puberty stage, and systolic blood pressure (SBP) was available. In young adulthood, demographics, anthropometrics, and fasting plasma samples were collected. Common CIMT and echogenicity, quantified as gray‐scale median (GSM), were evaluated using B‐mode ultrasonography. Lower and higher GSM values, respectively, represented lower and higher echogenicity. Associations of adolescent body mass index and SBP with young adulthood GSM and CIMT were evaluated using linear regression analysis. Mean age was 13.5 years in adolescence and 28.4 years in young adulthood (difference: 14.9 years). After full adjustment, adolescent body mass index related to GSM (β=−1.62/SD; 95% CI: −2.79, −0.46; P=0.006), independent of CIMT. Adolescent SBP did not relate to GSM. Moreover, adolescent body mass index (β=8.06 μm/SD [95% CI: 4.12, 11.99], P<0.001) and SBP (β=4.69 μm/SD [95% CI: 0.84, 8.54], P=0.02) related to CIMT. Conclusions Adolescent body mass index related to GSM and CIMT in young adulthood; SBP only related to CIMT. Hence, carotid intima‐media echogenicity appears to be involved in arterial wall remodeling, yet may mimic a different facet of this process than CIMT.

Relation Between Circulating Inflammatory Chemokines and Vascular Characteristics in Healthy, Young Children.

Background Atherosclerosis begins in childhood with the occurrence of inflammatory vascular wall alterations that are detectable with B‐mode ultrasound. Chemokines appear to be involved in the development of these alterations given that they occur early in the atherosclerotic pathway as mediators of vascular inflammation. However, this has not extensively been investigated. Therefore, we studied in healthy young children whether chemokines monocyte chemotactic protein 1 (MCP‐1), regulated on activation normal T‐cell expressed and secreted (RANTES), and vascular and intercellular adhesion molecules (VCAM and ICAM) related to vascular characteristics of the carotid artery. Methods and Results We obtained demography, anthropometry, and overnight fasting plasma of 139 eight‐year‐old children of the Wheezing Illnesses Study Leidsche Rijn birth cohort. Carotid intima‐media thickness (CIMT), distensibility, and Youngs Elastic Modulus (YEM) of the common carotid artery were measured sonographically. Chemokine plasma levels were assessed using a multiplex assay. We studied the relation between the chemokines and vascular characteristics using multivariable linear regression analyses with adjustments for sex, systolic blood pressure, homeostasis model assessment of insulin resistance, triglycerides, low‐density lipoprotein‐ and high‐density lipoprotein‐cholesterol. Of the studied chemokines, RANTES related to common carotid distensibility and YEM. One standard deviation increase in RANTES level related to a 5.45‐MPA −1 (95% confidence interval [CI], −9.43, −1.39; P=0.01) decrease in distensibility and to a 5.55‐kPa increase in YEM (95% CI, 0.40, 10.85; P=0.03). RANTES did not relate to CIMT. MCP‐1, VCAM, and ICAM did not relate to any of the studied vascular characteristics. Conclusion RANTES appears to be involved in the development of preatherosclerotic inflammatory vascular alterations already in healthy, young children. This may provide further insight into the early‐life origins of atherosclerosis.