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With the availability of massive amounts of data from electronic health records and registry databases, incorporating time-varying patient information to improve risk prediction has attracted great attention. To exploit the growing amount of predictor information over time, we develop a unified framework for landmark prediction using survival tree ensembles, where an updated prediction can be performed when new information becomes available. Compared to conventional landmark prediction with fixed landmark times, our methods allow the landmark times to be subject-specific and triggered by an intermediate clinical event. Moreover, the nonparametric approach circumvents the thorny issue of model incompatibility at different landmark times. In our framework, both the longitudinal predictors and the event time outcome are subject to right censoring, and thus existing tree-based approaches cannot be directly applied. To tackle the analytical challenges, we propose a risk-set-based ensemble procedure by averaging martingale estimating equations from individual trees. Extensive simulation studies are conducted to evaluate the performance of our methods. The methods are applied to the Cystic Fibrosis Foundation Patient Registry (CFFPR) data to perform dynamic prediction of lung disease in cystic fibrosis patients and to identify important prognosis factors.

Additional file 1.

BACKGROUND: Left ventricular (LV) subclinical remodeling is associated with adverse outcomes and indicates mechanisms of disease development. Standard metrics such as LV mass and volume may not capture the full range of remodeling. PURPOSE: To quantify relationships between LV 3D shape and incident cardiovascular events over 10-years. MATERIALS AND METHODS: 5,098 participants from the Multi-Ethnic Study of Atherosclerosis population, free of clinical cardiovascular disease, underwent cardiac magnetic resonance imaging in 2000–2002. LV shape models were automatically generated using a machine learning workflow. Event-specific remodeling signatures (RS) were computed using partial least squares regression, and random survival forests were used to determine which features were most associated with incident of heart failure (HF), coronary heart disease (CHD), and all cardiovascular events (CVD) over a 10-year follow-up period. The discrimination improvement of adding LV shape to traditional cardiovascular risk factors, coronary calcium score and NT-proBNP was assessed using the index of prediction accuracy and the time-dependent area under the receiver operating characteristic curve (AUC). Kaplan-Meier survival curves were used to illustrate the abilities of RS to predict the endpoints. RESULTS: 4,618 participants had sufficient 3D information to generate patient-specific LV models (age 60.6±9.9 years, 55% women). 147 HF, 317 CHD and 455 CVD events were observed. The addition of LV RS to traditional cardiovascular risk factors improved the 10-year AUC for prediction and achieved better performance than LV mass and volumes: HF (AUC: 0.83±0.01 and 0.81±0.01 respectively, p

Supplemental material, sj-pdf-1-vmj-10.1177_1358863X221122577 for Association of HIV infection with clinical features and outcomes of patients with aortic aneurysms by Omar Chehab, Amjad Kanj, Ralph Zeitoun, Tanveer Mir, Irfan Shafi, Mohit Pahuja, Alexandros Briasoulis, Henrique Doria de Vasconcellos, Anum Minhas, Vinithra Varadarajan, Colin Wu, Armin Arbab-Zadeh, Wendy S Post, Katherine C Wu and João AC Lima in Vascular Medicine

Supplemental material, sj-pdf-1-vmj-10.1177_1358863X221122577 for Association of HIV infection with clinical features and outcomes of patients with aortic aneurysms by Omar Chehab, Amjad Kanj, Ralph Zeitoun, Tanveer Mir, Irfan Shafi, Mohit Pahuja, Alexandros Briasoulis, Henrique Doria de Vasconcellos, Anum Minhas, Vinithra Varadarajan, Colin Wu, Armin Arbab-Zadeh, Wendy S Post, Katherine C Wu and João AC Lima in Vascular Medicine

Supplemental Material, sj-docx-1-jps-10.1177_24755303211000757 for Identifying Top Predictors of Change in Noncalcified Coronary Burden in Psoriasis by Machine Learning Over 1-Year by Eric Munger, Amit K. Dey, Justin Rodante, Martin P. Playford, Alexander V. Sorokin, Xin Tian, Colin O. Wu, Ahmed Hasan, Marcus Y. Chen, Joel M. Gelfand, Mohsin Saleet Jafri and Nehal N. Mehta in Journal of Psoriasis and Psoriatic Arthritis

Additional file 2. Association of right atrial volume with incident AF after adjustment for right ventricle variables. EF: emptying fraction; EDM: end-diastolic mass. Models are also adjusted for demographics and traditional risk factors.

Additional file 1. Correlation of AF risk factors and RA volume at study initiation. SD: Standard deviation; BMI: Body mass index. Association of risk factors for AF and RA volume indices is shown. RA volume was generally not significantly different for risk factors though demographic differences by sex and race are evident. Volume is indexed by body-surface area which may affect the significance risk factors due to collinearity.

Additional file 3. Baseline characteristics of patients who did and did not receive cardiac magnetic resonance imaging. Values are mean ± SD or %. CMR: cardiovascular magnetic resonance imaging; SD: Standard deviation; BMI: Body mass index; HDL: High density lipoprotein.

The predictive value of aortic arch pulse wave velocity (PWV) assessed by magnetic resonance imaging (MRI) for cardiovascular disease (CVD) events has not been fully established. The aim of the present study was to evaluate the association of arch PWV with incident CVD events in MESA. Aortic arch PWV was measured using MRI at baseline in 3,527 MESA participants (mean age = 62 ± 10 years at baseline, 47% male) free of overt CVD. Cox regression was used to evaluate the risk of incident CVD (coronary heart disease, stroke, transient ischemic attack, or heart failure) in relation to arch PWV adjusted for age, gender, race, and CVD risk factors. The median value of arch PWV was 7.4 (IQR; 5.6 to 10.2) m/s. There was significant interaction between arch PWV and age for outcomes, so analysis was stratified by age categories (45–54 and over 54 years). There were 456 CVD events over the 10-year follow-up. 45–54 year-old participants had significant association of arch PWV with incident CVD independent of CVD risk factors (HR, 1.44; 95% confidence interval, 1.07 to 1.95; p=0.018; per 1SD increase for logarithmically transformed PWV), whereas over 54 years group did not (p=0.93). Aortic arch PWV assessed by MRI is a significant predictor of CVD events among middle-aged (45 to 54 years old) individuals, whereas arch PWV is not associated with CVD among an elderly in a large multi-ethnic population.

Using extreme phenotypes for association studies can improve statistical power . We study the impact of using samples with extremely high or low traits on the alternative model space, the genotype relative risks, and the genetic models in association studies. We prove the following results: when the risk allele causes high-trait values, the more extreme the high traits, the larger the genotype relative risks, which is not always true for using extreme low traits; we also prove that a genetic model theoretically changes with more extreme trait except for the recessive or dominant models. Practically, however, the impact of deviations from the true genetic model at a functional locus due to selective sampling is virtually negligible. The implications of our findings are discussed. Numerical values are reported for illustrations.

Regulation of translocation polarity by helicase domain 1 in SF2B helicases Biochemical and reverse footprinting studies of the nucleotide excision repair protein XPD show that opposing translocation polarity in superfamily II A and B helicases is an intrinsic property of their respective motor domains, rather than related to different relative DNA binding orientations., Structurally similar superfamily I (SF1) and II (SF2) helicases translocate on single-stranded DNA (ssDNA) with defined polarity either in the 5′–3′ or in the 3′–5′ direction. Both 5′–3′ and 3′–5′ translocating helicases contain the same motor core comprising two RecA-like folds. SF1 helicases of opposite polarity bind ssDNA with the same orientation, and translocate in opposite directions by employing a reverse sequence of the conformational changes within the motor domains. Here, using proteolytic DNA and mutational analysis, we have determined that SF2B helicases bind ssDNA with the same orientation as their 3′–5′ counterparts. Further, 5′–3′ translocation polarity requires conserved residues in HD1 and the FeS cluster containing domain. Finally, we propose the FeS cluster-containing domain also provides a wedge-like feature that is the point of duplex separation during unwinding.

Background: Left atrial (LA) remodeling in response to cardiovascular and hemodynamic stress may precede atrial fibrillation (AF) and heart failure (HF). We hypothesized that LA systolic synchronous contraction as a functional measure of LA remodeling is deranged in patients with paroxysmal AF and HF. Methods: We performed a nested case-control analysis with 1:2 matching for 39 cases of paroxysmal AF (n=28, in sinus rhythm during cardiac magnetic resonance (CMR)) and HF (n=14, AF+HF; n=3) and 78 controls with similar demographic and clinical characteristics at the baseline (Table 1). LA circumferential (short axis) and longitudinal strain rate (horizontal long axis) were measured using Multi-modality Tissue Tracking (Toshiba, Japan) from short and long-axis cine CMR images. Circumferential LA systolic dyssynchrony among 18 LA segments (6 segments x 3 slices) was evaluated as; Standard Deviation (SD) of time to pre atrial contraction Strain rate (PreA Src) and Peak systolic strain rate (Peak Srac) (Figure 1). Similarly, longitudinal LA dyssynchrony parameters (among 6 segments) were: SD-Time to pre-atrial contraction strain rate (PreA SrL) and SD-Time to peak systolic strain rate (Peak-SraL). Wilcoxon-rank sum test (non-parametric) or two sample t-test (parametric) were used for comparison between the groups. Results: In participants during MESA exam 5 (age 74±8 years, 51.4% men), systolic circumferential dyssynchrony (SD-TP-PreA Src, msec) was significantly higher in the cases compared to controls (45.06 vs. 28.73, p

Fundamento: A doença cardiovascular subclínica é prevalente em pacientes com síndrome metabólica (SM). O strain circunferencial (εCC) e o strain longitudinal (εLL) do ventriculo esquerdo (VE), avaliados pelo ecocardiograma com speckle tracking (STE), são índices de função sistólica: o encurtamento das fibras circunferenciais e longitudinais do VE é indicado por um valor negativo do strain. Portanto, quanto mais negativo o strain, melhor a função sistólica do VE. O εCC e o εLL têm sido usados para demonstrar disfunção ventricular subclínica em vários distúrbios clínicos. Objetivo: Levantamos a hipótese de que a SM está associada com comprometimento da função miocárdica, quando avaliada pelo STE. Métodos: Este estudo analisou participantes do Multi-Ethnic Study of Atherosclerosis (MESA) que realizaram o STE e foram avaliados para todos os componentes da SM. Resultados: Entre os 133 participantes incluídos (mulheres: 63%; idade: 65 ± 9 anos), a prevalência de SM foi de 31% (41/133). Indivíduos com SM apresentaram valores menores do εCC e do εLL que aqueles sem SM (-16,3% ± 3,5% vs. -18,4% ± 3,7%, p < 0,01; e -12,1% ± 2,5% vs. -13,9% ± 2,3%, p < 0,01, respectivamente). A fração de ejeção do VE (FEVE) foi semelhante nos dois grupos (p = 0,09). Na análise multivariada, a SM associou-se a um valor mais baixo do strain circunferencial (B = 2,1%, IC 95%: 0,6-3,5; p < 0,01), mesmo após ajuste para idade, etnia, massa VE e FEVE. De maneira semelhante, a presença de SM (B = 1,3%, IC 95%: 0,3-2,2; p < 0,01) e a massa do VE (B = 0,02%, IC 95%: 0,01 0,03; p = 0,02) associaram-se a um valor menor do strain longitudinal após ajuste para etnia, FEVE e creatinina. Conclusão: O εCC e o εLL do VE, marcadores de doença cardiovascular subclínica, estão comprometidos em indivíduos assintomáticos com SM e sem história prévia de infarto miocárdico, insuficiência cardíaca e/ou de FEVE < 50%. Background: Subclinical cardiovascular disease is prevalent in patients with Metabolic Syndrome (MetSyn). Left ventricular (LV) circumferential strain (εCC) and longitudinal strain (εLL), assessed by Speckle Tracking Echocardiography (STE), are indices of systolic function: shortening is indicated by negative strain, and thus, the more negative the strain, the better the LV systolic function. They have been used to demonstrate subclinical ventricular dysfunction in several clinical disorders. Objective: We hypothesized that MetSyn is associated with impaired myocardial function, as assessed by STE. Methods: We analyzed Multi-Ethnic Study of Atherosclerosis (MESA) participants who underwent STE and were evaluated for all MetSyn components. Results: Among the 133 participants included [women: 63%; age: 65 ± 9 years (mean ± SD)], the prevalence of MetSyn was 31% (41/133). Individuals with MetSyn had lower εCC and lower εLL than those without MetSyn (-16.3% ± 3.5% vs. -18.4% ± 3.7%, p < 0.01; and -12.1% ± 2.5% vs. -13.9% ± 2.3%, p < 0.01, respectively). The LV ejection fraction (LVEF) was similar in both groups (p = 0.09). In multivariate analysis, MetSyn was associated with less circumferential myocardial shortening as indicated by less negative εCC (B = 2.1%, 95%CI:0.6 3.5, p < 0.01) even after adjusting for age, ethnicity, LV mass, and LVEF). Likewise, presence of MetSyn (B = 1.3%, 95%CI:0.3 2.2, p < 0.01) and LV mass (B = 0.02%, 95% CI: 0.01-0.03, p = 0.02) were significantly associated with less longitudinal myocardial shortening as indicated by less negative εLL after adjustment for ethnicity, LVEF, and creatinine. Conclusion: Left ventricular εCC and εLL, markers of subclinical cardiovascular disease, are impaired in asymptomatic individuals with MetSyn and no history of myocardial infarction, heart failure, and/or LVEF < 50%.

Tagged cardiac magnetic resonance provides detailed information on regional myocardial function and mechanical behavior. T1 mapping by cardiac magnetic resonance allows noninvasive quantification of myocardial extracellular expansion (ECE), which has been related to interstitial fibrosis in previous clinical and subclinical studies. We assessed sex-associated differences in the relation of ECE to left ventricular (LV) remodeling and myocardial systolic and diastolic deformation in a large community-based multiethnic population.Midventricular midwall peak circumferential shortening and early diastolic strain rate and LV torsion and torsional recoil rate were determined using cardiac magnetic resonance tagging. Midventricular short-axis T1 maps were acquired in the same examination pre- and postcontrast injection using Modified Look-Locker Inversion-Recovery sequence. Multivariable linear regression (estimated regression coefficient, B) was used to adjust for risk factors and subclinical disease measures. Of 1230 participants, 114 had a visible myocardial scar by late gadolinium enhancement. Participants without a visible myocardial scar (n=1116) had no history of previous clinical events. In the latter group, multivariable linear regression demonstrated that lower postcontrast T1 times, reflecting greater ECE, were associated with lower circumferential shortening (B=-0.1; P=0.0001), lower LV end-diastolic volume index (B=0.6; P=0.0001), and lower LV end-diastolic mass index (B=0.4; P=0.0001). In addition, lower postcontrast T1 times were associated with lower early diastolic strain rate (B=0.01; P=0.03) in women only and lower LV torsion (B=0.005; P=0.03) and lower LV ejection fraction (B=0.2, P=0.01) in men only.Greater ECE is associated with reduced LV end-diastolic volume index and LV end-diastolic mass index in a large multiethnic population without history of previous cardiovascular events. In addition, greater ECE is associated with reduced circumferential shortening, lower early diastolic strain rate, and a preserved ejection fraction in women, whereas in men, greater ECE is associated with greater LV dysfunction manifested as reduced circumferential shortening, reduced LV torsion, and reduced ejection fraction.

Using extreme phenotypes for association studies can improve statistical power . We study the impact of using samples with extremely high or low traits on the alternative model space, the genotype relative risks, and the genetic models in association studies. We prove the following results: when the risk allele causes high-trait values, the more extreme the high traits, the larger the genotype relative risks, which is not always true for using extreme low traits; we also prove that a genetic model theoretically changes with more extreme trait except for the recessive or dominant models. Practically, however, the impact of deviations from the true genetic model at a functional locus due to selective sampling is virtually negligible. The implications of our findings are discussed. Numerical values are reported for illustrations.

The authors investigated 3 important areas related to the clinical use of left ventricular mass (LVM): accuracy of assessments by echocardiography and cardiac magnetic resonance (CMR), the ability to predict cardiovascular outcomes, and the comparative value of different indexing methods. The recommended formula for echocardiographic estimation of LVM uses linear measurements and is based on the assumption of the left ventricle (LV) as a prolate ellipsoid of revolution. CMR permits a modeling of the LV free of cardiac geometric assumptions or acoustic window dependency, showing better accuracy and reproducibility. However, echocardiography has lower cost, easier availability, and better tolerability. From the MEDLINE database, 26 longitudinal echocardiographic studies and 5 CMR studies investigating LVM or LV hypertrophy as predictors of death or major cardiovascular outcomes were identified. LVM and LV hypertrophy were reliable cardiovascular risk predictors using both modalities. However, no study directly compared the methods for the ability to predict events, agreement in hypertrophy classification, or performance in cardiovascular risk reclassification. Indexing LVM to body surface area was the earliest normalization process used, but it seems to underestimate the prevalence of hypertrophy in obese and overweight subjects. Dividing LVM by height to the allometric power of 1.7 or 2.7 is the most promising normalization method in terms of practicality and usefulness from a clinical and scientific standpoint for scaling myocardial mass to body size. The measurement of LVM, calculation of LVM index, and classification for LV hypertrophy should be standardized by scientific societies across measurement techniques and adopted by clinicians in risk stratification and therapeutic decision making.

International audience; Arterial stiffness predicts cardiovascular events beyond traditional risk factors. However, the relationship with aging of novel noninvasive measures of aortic function by MRI and their interrelationship with established markers of vascular stiffness remain unclear and currently limit their potential impact. Our aim was to compare age-related changes of central measures of aortic function with carotid distensibility, global carotid-femoral pulse wave velocity, and wave reflections. We determined aortic strain, distensibility, and aortic arch pulse wave velocity by MRI, carotid distensibility by ultrasound, and carotid-femoral pulse wave velocity by tonometry in 111 asymptomatic subjects (54 men, age range: 20 to 84 years). Central pressures were used to calculate aortic distensibility. Peripheral and central pulse pressure, augmentation index, and carotid-femoral pulse wave velocity increased with age, but aortic strain and aortic arch PWV were most closely and specifically related to aging. Ascending aortic (AA) strain and distensibility decreased, respectively, by 5.3+/-0.5% (R(2)=0.54, P

BACKGROUND AND PURPOSE: The relevance of cavernous carotid artery calcification on unenhanced CT scans of the brain has recently been investigated against the backdrop of the widespread implementation of coronary artery calcification scoring. We sought to determine whether the degree of cavernous carotid artery calcification correlated with scores of white matter hyperintensity seen on MR images. In so doing, we sought to establish a relative risk for future stroke on the grade of carotid calcification. METHODS: Neuroradiologic findings in 187 patients who underwent CT and MR imaging examinations within 1 month of each other were retrospectively reviewed. The degree of circumferential calcification and thickness of calcification were graded for the cavernous carotid arteries on the basis of CT findings. Using the scale developed by the Cardiovascular Health Study, the white matter was graded for degree of disease on the basis of MR findings. Correlation tests and regression analyses were performed to determine the impact of age, race, and sex on results. RESULTS: Although the cavernous carotid calcification scores and the MR imaging white matter scores showed good correlation (P < .001), the effect was mediated by age. With age factored in as a covariant, no correlation was shown between CT calcification scores and MR imaging white matter scores. Sex had no effect, but African American study participants had worse MR imaging white matter scores than did white participants. CONCLUSION: After adjusting for age, cavernous carotid calcification grades and MR imaging white matter scores do not show a significant correlation. The relative risk for future stroke cannot be predicted from cavernous carotid calcifications.

ObjectivesWe sought to examine the prognostic value of subclinical left ventricular (LV) regional myocardial dysfunction (RMD) measured by magnetic resonance imaging (MRI) among asymptomatic individuals.BackgroundLV RMD, defined as segmental impairment in systolic wall thickening, predicts adverse events in patients with established cardiovascular disease. MRI is highly accurate for detecting subtle RMD, of which the prognostic significance in a large multiethnic asymptomatic population is not known.MethodsWe used MRI to evaluate baseline regional LV myocardial function and prospectively followed a multiethnic (African American, Caucasian, Chinese, and Hispanic) population-based sample of 4,510 men and women without cardiovascular disease for a mean of 4.6 years. Regional myocardial dysfunction was defined as the presence of impaired systolic wall thickening (

BackgroundCumulative blood pressure (BP) exposure may adversely influence myocardial function, predisposing individuals to heart failure later in life.ObjectivesThis study sought to investigate how cumulative exposure to higher BP influences left ventricular (LV) function during young to middle adulthood.MethodsThe CARDIA (Coronary Artery Risk Development in Young Adults) study prospectively enrolled 5,115 healthy African Americans and whites in 1985 and 1986 (baseline). At the year 25 examination, LV function was measured by 2-dimensional echocardiography; cardiac deformation was assessed in detail by speckle-tracking echocardiography. We used cumulative exposure of BP through baseline and up to the year 25 examination (millimeters of mercury × year) to represent long-term exposure to BP levels. Linear regression and logistic regression were used to quantify the association of BP measured repeatedly through early adulthood (18 to 30 years of age) up to middle age (43 to 55 years).ResultsAmong 2,479 participants, cumulative BP measures were not related to LV ejection fraction; however, high cumulative exposure to systolic blood pressure (SBP) and diastolic blood pressure (DBP) were associated with lower longitudinal strain rate (both p < 0.001). For diastolic function, higher cumulative exposures to SBP and DBP were associated with low early diastolic longitudinal peak strain rate. Of note, higher DBP (per SD increment) had a stronger association with diastolic dysfunction compared with SBP.ConclusionsHigher cumulative exposure to BP over 25 years from young adulthood to middle age is associated with incipient LV systolic and diastolic dysfunction in middle age.

ObjectivesThe objective of this study was to investigate the relationship between baseline resting heart rate and incidence of heart failure (HF) and global and regional left ventricular (LV) dysfunction.BackgroundThe association of resting heart rate to HF and LV function has not been well described in an asymptomatic multi-ethnic population.MethodsResting heart rate was measured in participants in the MESA (Multi-Ethnic Study of Atherosclerosis) trial at inclusion. Incident HF was registered (n = 176) during follow-up (median 7 years) in those who underwent cardiac magnetic resonance imaging (n = 5,000). Changes in ejection fraction (ΔEF) and peak circumferential strain (Δεcc) were measured as markers of developing global and regional LV dysfunction in 1,056 participants imaged at baseline and 5 years later. Time to HF (Cox model) and Δεcc and ΔEF (multiple linear regression models) were adjusted for demographics, traditional cardiovascular risk factors, calcium score, LV end-diastolic volume, and mass in addition to resting heart rate.ResultsCox analysis demonstrated that for 1 beat/min increase in resting heart rate, there was a 4% greater adjusted relative risk for incident HF (hazard ratio: 1.04; 95% CI: 1.02 to 1.06; p < 0.001). Adjusted multiple regression models demonstrated that resting heart rate was positively associated with deteriorating εcc and decrease in EF, even when all coronary heart disease events were excluded from the model.ConclusionsElevated resting heart rate was associated with increased risk for incident HF in asymptomatic participants in the MESA trial. Higher heart rate was related to development of regional and global LV dysfunction independent of subclinical atherosclerosis and coronary heart disease. (Multi-Ethnic Study of Atherosclerosis [MESA]; NCT00005487)

ObjectivesWe sought to define age-related geometric changes of the aortic arch and determine their relationship to central aortic stiffness and left ventricular (LV) remodeling.BackgroundThe proximal aorta has been shown to thicken, enlarge in diameter, and lengthen with aging in humans. However, no systematic study has described age-related longitudinal and transversal remodeling of the aortic arch and their relationship with LV mass and remodeling.MethodsWe studied 100 subjects (55 women, 45 men, average age 46±16 years) free of overt cardiovascular disease using magnetic resonance imaging to determine aortic arch geometry (length, diameters, height, width, and curvature), aortic arch function (local aortic distensibility and arch pulse wave velocity [PWV]), and LV volumes and mass. Radial tonometry was used to calculate central blood pressure.ResultsAortic diameters and arch length increased significantly with age. The ascending aorta length increased most, with age leading to aortic arch widening and decreased curvature. These geometric changes of the aortic arch were significantly related to decreased ascending aortic distensibility, increased aortic arch PWV (p < 0.001), and increased central blood pressures (p < 0.001). Increased ascending aortic diameter, lengthening, and decreased curvature of the aortic arch (unfolding) were all significantly associated with increased LV mass and concentric remodeling independently of age, sex, body size, and central blood pressure (p < 0.01).ConclusionsAge-related unfolding of the aortic arch is related to increased proximal aortic stiffness in individuals without cardiovascular disease and associated with increased LV mass and mass-to-volume ratio independent of age, body size, central pressure, and cardiovascular risk factors.

ObjectivesThis study sought to determine the relationship of cardiovascular magnetic resonance (CMR) measures of tissue composition to age in the Multi-Ethnic Study of Atherosclerosis (MESA).BackgroundAnimal and human studies have demonstrated increased collagen deposition in senescent hearts. New CMR indices of tissue composition by using T1 mapping are sensitive to the presence of myocardial fibrosis.MethodsA total of 1,231 study participants (51% women; age range 54 to 93 years) of the MESA cohort were evaluated with T1 mapping by using 1.5-T CMR scanners. None of the participants had focal scar on delayed enhancement CMR. Single-slice T1 mapping was performed at the midventricular level before and at 12- and 25-min delay after administration of gadolinium contrast by using a modified Look-Locker inversion recovery sequence. The partition coefficient was determined by the slope of the linear relationship of (1/T1myo vs. 1/T1blood). The extracellular volume fraction (ECV) was derived accounting for the hematocrit level. Multivariable regression analyses were performed, adjusting for traditional risk factors and left ventricular structure.ResultsWomen had significantly greater partition coefficient, ECV, and precontrast T1 than men, as well as lower post-contrast T1 values (all p < 0.05). In general, linear regression analyses demonstrated that greater partition coefficient, pre-contrast T1 values, and ECV were associated with older age in men (multivariate regression coefficients = 0.01; 5.9 ms; and 1.04% per 10 years' change; all p < 0.05). ECV was also significantly associated with age in women after multivariable adjustments.ConclusionsCMR parameters that have been associated with myocardial fibrosis were related to older age in the MESA study. Women had higher ECV than men but less ECV change over time.

BackgroundThe predictive value of ascending aortic distensibility (AAD) for mortality and hard cardiovascular disease (CVD) events has not been fully established.ObjectivesThis study sought to assess the utility of AAD to predict mortality and incident CVD events beyond conventional risk factors in MESA (Multi-Ethnic Study of Atherosclerosis).MethodsAAD was measured with magnetic resonance imaging at baseline in 3,675 MESA participants free of overt CVD. Cox proportional hazards regression was used to evaluate risk of death, heart failure (HF), and incident CVD in relation to AAD, CVD risk factors, indexes of subclinical atherosclerosis, and Framingham risk score.ResultsThere were 246 deaths, 171 hard CVD events (myocardial infarction, resuscitated cardiac arrest, stroke and CV death), and 88 HF events over a median 8.5-year follow-up. Decreased AAD was associated with increased all-cause mortality with a hazard ratio (HR) for the first versus fifth quintile of AAD of 2.7 (p = 0.008) independent of age, sex, ethnicity, other CVD risk factors, and indexes of subclinical atherosclerosis. Overall, patients with the lowest AAD had an independent 2-fold higher risk of hard CVD events. Decreased AAD was associated with CV events in low to intermediate- CVD risk individuals with an HR for the first quintile of AAD of 5.3 (p = 0.03) as well as with incident HF but not after full adjustment.ConclusionsDecreased proximal aorta distensibility significantly predicted all-cause mortality and hard CV events among individuals without overt CVD. AAD may help refine risk stratification, especially among asymptomatic, low- to intermediate-risk individuals.

Methods; CINE Cardiovascular magnetic resonance/ Torsion and Myocardial Strain Analysis/ Left ventricular indices/ Risk factor measures. (DOCX 636 kb)

Methods; CINE Cardiovascular magnetic resonance/ Torsion and Myocardial Strain Analysis/ Left ventricular indices/ Risk factor measures. (DOCX 636 kb)