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Introduction: The role of the right atrium (RA) in the pathogenesis and prediction of cardiovascular disease has been increasingly recognized, however the effects of aging on the RA remain unknown. In this longitudinal study we sought to describe the structural and functional changes in the RA over approximately ten years and explore their association with demographic and clinical risk factors. Methods: We included 1509 participants who had cardiovascular magnetic resonance at Exam 1 (2000-2002) and follow-up at Exam 5 (2009-2010) with adequate quality RA imaging at both timepoints. Quantification was performed using multimodality tissue tracking software, which has been extensively validated previously. Volumes were indexed to body-surface area. Adjusted multivariate linear regression used for analysis. Results: Participants were on average 58 years old at study onset, 54% female, 43% white, 14% Chinese American, 25% black, and 18% Hispanic. Over 10 years, RA indexed maximum and minimum volumes increased by 32% (8.8 mL/m2) and 37% (5.2 mL/m2) respectively. RA emptying fraction (EF) decreased by 1.3% and global strain trended towards a 0.7% decrease. Older age was associated with greater increases in volume but smaller decreases in function. Men had greater increase in volume and decrease in function, as did black and white races. Baseline obesity (BMI≥30), smoking, and diabetes status were all associated with greater decreases in function. Baseline use of ACE-inhibitors, lipid-lowering medications, and antihypertensives were not associated with larger or smaller changes in structure or function. Conclusions: In this large, diverse participant cohort, RA volumes substantially increased and function decreased over 10 years of follow-up. These differences were generally more prominent among men, older individuals, and white and black participants, and were further associated with baseline clinical risk factors.

OBJECTIVE We investigated the association of cardiovascular risk factors and myocardial fibrosis with early cardiac dysfunction in type 1 diabetes. RESEARCH DESIGN AND METHODS Participants with type 1 diabetes aged 13–39 years without a known history of cardiovascular disease (CVD) (n = 1,441) were recruited into the Diabetes Control and Complications Trial (1983–1993) and subsequently followed in the Epidemiology of Diabetes Interventions and Complications study (1994 to present). Seven hundred fourteen participants underwent cardiac magnetic resonance (CMR) imaging (2007–2009) with late gadolinium enhancement sequences to assess ischemic and nonischemic scars and tagging sequences to evaluate circumferential strain. CMR-derived T1 mapping also was used to assess interstitial fibrosis. The influence of cardiovascular risk factors and myocardial scar on circumferential strain was assessed using linear regression. RESULTS Circumferential dysfunction was consistently associated with older age, male sex, smoking history, obesity, higher blood pressure, lower HDL cholesterol, and higher mean HbA1c. Participants with nonischemic scars (n = 16) had the worst circumferential function compared with those without scars (β ± SE 1.32 ± 0.60; P = 0.03). In sex-adjusted models, the correlation between T1 times and circumferential strain was not significant. In the fully adjusted models, a trend toward circumferential dysfunction in participants with nonischemic scars was found. Left ventricular ejection fraction was not associated with risk factors but was significantly lower if a myocardial scar was present. CONCLUSIONS Traditional CVD risk factors and elevated HbA1c levels are major factors related to early cardiac dysfunction in type 1 diabetes. Nonischemic myocardial scar, possibly as a marker of chronic exposure to known risk factors, may predict early cardiac dysfunction mediated by diffuse myocardial fibrosis as seen in diabetic cardiomyopathy.

Aims To assess the test–retest, intra- and inter-reader reliability of thoracic aorta measurements by magnetic resonance imaging (MRI). Methods and results Twenty-five participants underwent aortic MRI twice over 13 ± 7 days. All aortic variables from baseline and repeat MR were analysed using a semi-automated method by the ARTFUN software. To assess the inter-study reproducibility of aortic variables, we calculated intraclass correlation coefficient (ICC) for individual aortic measurements. Intra- and inter-observer variability was also assessed using the baseline MR data. Mean ascending aortic strain had moderate inter-study reproducibility (11.53 ± 6.44 vs. 10.55 ± 6.64, P = 0.443, ICC = 0.53, P < 0.01). Mean descending aortic strain and arch pulse wave velocity (PWV) had good inter-study reproducibility (descending aortic strain: 8.65 ± 5.30 vs. 8.35 ± 5.26, P = 0.706, ICC = 0.74, P < 0.001; PWV: 9.92 ± 4.18 vs. 9.94 ± 4.55, P = 0.968, ICC = 0.77, P < 0.001, respectively). All aortic variables had excellent intra- and inter-observer reproducibility (intra-: ICC range, 0.87–0.99, inter-: ICC range, 0.56–0.99, respectively). Conclusion Inter-study reproducibility of all aortic variables was acceptable. Intra- and inter-observer reproducibility of all aortic variables was excellent. MRI can provide a repeatable method of measuring aortic structural and functional parameters.

Transthoracic Doppler echocardiography is recommended for screening for the presence of pulmonary hypertension (PH). However, some recent studies have suggested that Doppler echocardiographic pulmonary artery pressure estimates may frequently be inaccurate.Evaluate the accuracy of Doppler echocardiography for estimating pulmonary artery pressure and cardiac output.We conducted a prospective study on patients with various forms of PH who underwent comprehensive Doppler echocardiography within 1 hour of a clinically indicated right-heart catheterization to compare noninvasive hemodynamic estimates with invasively measured values.A total of 65 patients completed the study protocol. Using Bland-Altman analytic methods, the bias for the echocardiographic estimates of the pulmonary artery systolic pressure was -0.6 mm Hg with 95% limits of agreement ranging from +38.8 to -40.0 mm Hg. Doppler echocardiography was inaccurate (defined as being greater than +/-10 mm Hg of the invasive measurement) in 48% of cases. Overestimation and underestimation of pulmonary artery systolic pressure by Doppler echocardiography occurred with a similar frequency (16 vs. 15 instances, respectively). The magnitude of pressure underestimation was greater than overestimation (-30 +/- 16 vs. +19 +/- 11 mm Hg; P = 0.03); underestimates by Doppler also led more often to misclassification of the severity of the PH. For cardiac output measurement, the bias was -0.1 L/min with 95% limits of agreement ranging from +2.2 to -2.4 L/min.Doppler echocardiography may frequently be inaccurate in estimating pulmonary artery pressure and cardiac output in patients being evaluated for PH.

Introduction: Increased left atrial (LA) size and reduced LA function are known predictors of atrial fibrillation (AF). Evidence also links increased LA size and stroke. We sought to examine the association of LA function, measured with cardiac magnetic resonance imaging (CMR) and incident stroke/TIA and dementia. Methods: This case-cohort study compared LA size and function in 180 MESA participants with incident Stroke/TIA and 95 with incident dementia, over a median follow up of 10.7 years, to 550 participants randomly selected from the whole MESA cohort. All individuals were free of clinical cardiovascular and major valvular heart disease. Phasic LA volumes, LA emptying fractions (LAEF) and peak strain were quantified in sinus rhythm using tissue-tracking CMR. Vascular neurologists adjudicated stroke events by medical record review. Dementia cases were identified using ICD9 codes from hospital records. Modified Cox proportional hazard models weighted for the stratified case-cohort sampling design was used to examine the associations. Results: Incident Stroke/TIA (age 67 ± 9 years, 45% male) and dementia cases (age 74 ± 6 years, 58% male) were older than the subcohort population (age: 61 ± 10, 49% male). In multivariable analysis adjusted for standard cardiovascular risk factors and left ventricular ejection fraction, lower peak LA strain and passive LAEF were associated with both incident stroke/TIA and dementia. After further adjustment for incident AF, the associations were attenuated for peak LA strain but remained significant for passive LAEF (HR for incident Stroke/TIA: 0.72 per SD 95% CI: 0.55-0.93, p=0.013 and for incident dementia: 0.59 per SD 95% CI: 0.37-0.95, p=0.031). Conclusions: Reduced LA conduit function was associated with incident Stroke/TIA and dementia independent of other cardiovascular risk factors and incident AF. Assessment of LA function may add further information in risk stratifying individuals at risk for stroke and dementia.

Background Left atrium (LA) strain, volume and function are important markers of cardiovascular disease and myocardial impairment. We aimed to assess the accuracy of LA biplane volume and function measured by Multimodality Tissue Tracking (MTT). Also we assessed the inter-study reproducibility for cardiovascular magnetic resonance (CMR) derived LA volume and function parameters. Methods Thirty subjects (mean age: 71.3 ± 8.7, 87 % male) including twenty subjects with cardiovascular events and ten healthy subjects, with CMR were evaluated in the Multi-Ethnic Study of Atherosclerosis (MESA). LA volumes were computed by the modified biplane method from 2- and 4-chamber projections and the Simpson’s method from short-axis slices using both methods - manual and semi-automated delineation using MTT. LA total, active and passive ejection fractions were calculated. Pearson’s correlation and Bland-Altman analysis were used to compare the measurements. In a second sample of 25 subjects (age: 65.7 ± 7.1, 72 % males) inter study, intra and inter reader reliability analysis was performed. The intra-class correlation coefficient (ICC) was evaluated. Results Left atrial MTT structural and functional parameters were not different from manual delineation, yet image analysis was only half as time consuming on average with MTT. Maximal volume MTT was not different between the Simpson’s and Biplane methods, functional parameters, however were different. MTT allowed us to measure multiple LA parameters with good-excellent (ICC; 0.88– 0.98, p

Background Steady-state free precession (SSFP) results in larger volumes and lower ejection fraction for the left ventricle compared to fast gradient echo (fGRE) imaging. Similar comparisons for the left atrium (LA) are not available and may be relevant for 3T imaging and historical comparison to prior imaging datasets. As opposed to LV imaging, volumes in the LA are more commonly derived using biplane area measurements.

Background Left atrium (LA) volume and function are important markers of cardiovascular disease. LA volume can be assessed by several different methods. In clinical practice, the Simpson’s method is well accepted as a reference standard, although there is no standardization for LA volume calculations. We aimed to compare the estimations of LA volume by the Simpson’s method and the modified biplane Simpson’s method; and to introduce Multimodality Tissue Tracking (MTT, Japan, Toshiba) as a new semi-automated method for quantifying LA function based on tissue feature tracking. Methods Thirty subjects (mean age: 71.3 ± 8.7, 87% male) including twenty subjects with cardiovascular events (4 atrial fibrillation, 18 myocardial scar from late gadolinium enhancement, 2 heart failure) and ten healthy subjects, with CMR imaging were evaluated in the Multi-Ethnic Study of Atherosclerosis (MESA). LA volumes were measured using the modified biplane Simpson’ sm ethod from 2- and 4-chamber projections and the original Simpson’s method using short-axis slices. For the manual methods, LA endo- and epicardial boundaries were delineated at left-ventricular end-diastole (Vmin), end-systole (Vmax) and just before the pre-atrial contraction (VpreA). Using MTT, LA endocardial and epicardial borders were manually delineated at end-systole and the boundaries were propagated automatically throughout the cardiac

Methods LA volume indexed to body surface area (LAVi) was measured by CMR using steady-state free precession cine long and short axis images in 2576 participants of the MultiEthnic Study of Atherosclerosis (68.7 years, 53.0% women). We used gender stratified regression models to evaluate the association of LAVi as the dependent variable with demographic and cardiovascular risk factors, left ventricular (LV) parameters and diagnosis of coronary heart disease as independent variables. LAVi between ethnicities were compared using analysis of variance (ANOVA) with Tukey’s post-hoc analysis. To determine normal LA dimensions we also selected a group of participants with normal body mass index (≥18.5 and < 25 kg/m), without hypertension, diabetes, coronary heart disease, congestive heart failure, LV systolic dysfunction (defined as ejection fraction less than 50%), LV hypertrophy or atrial fibrillation (n = 285, 65.6 years, 61.8% women). Results The unadjusted mean LA volume index in the whole cohort was 36.5 ± 11.4 ml/m and was 9% smaller in men (35.9 ± 11.1 vs. 37.0 ± 11.6 ml/m, p < 0.05). LAVi was greater with age in men (b = 0.2 ml/m/yr, p < 0.0001) and women (b = 0.3 ml/m/yr, p < 0.0001). Both Chinese American men and women had significantly (p < 0.05) smaller LAVi compared to other ethnicities (Figure 2). History of coronary disease was associated with 10% larger LAVi in women (b=3.7 ml/m, p < 0.05), but not in men (p = ns). In the normal reference cohort free of cardiovascular disease there were no differences in LAVi by gender (men 34.5 ± 9.9 ml/m, women 36.0 ± 10.2 ml/m, p = 0.30).

Methods 114 participants age >65 years were enrolled in a double blinded randomized trial as part of the NIA Plaque study. Participants were randomly assigned to two treatment groups; one receiving simvastatin and niacin and other receiving simvastatin and placebo. Baseline MRI was performed on all participants using a 1.5-Tesla scanner. Follow-up MRI exams were done every 6 months for 18 months. Axial images of 3 segments of the thoracic aorta (ascending, arch and descending) were obtained using a double inversion recovery black blood fast spin-echo sequence with ECG-gating. 0.1 mmol/kg of gadodiamide contrast was given intravenously. Post contrast T1weighted images were used to evaluate the changes in vessel wall thickness and lumen diameter over the course of lipid therapy. Paired t test and multivariable regression were used for data analyses.

Methods Twenty-five participants underwent aortic MRI twice over 13 ± 7 days. All aortic variables (ascending aortic area, descending aortic area, ascending and descending aortic strain [maximum area minus minimum area divided by minimum area], aortic arch transit time and pulse wave velocity [PWV]) from baseline and repeat MR were analyzed using a semi-automated method by the ARTFUN software. Phase contrast (PC) cine at the level of the pulmonary artery bifurcation was used for assessment of aortic area, aortic strain, and PWV. Steady State Free Precession (SSFP) sagittal images were used to measure aortic arch transit distance. To assess the inter-study reproducibility of aortic variables, we calculated intraclass correlation coefficient (ICC) for individual aortic measurements. Intraand inter-observer variability was also assessed using the baseline MR data.

Right ventricular (RV) function is an important determinant of prognosis in pulmonary hypertension. However, noninvasive assessment of the RV function is often limited by complex geometry and poor endocardial definition.To test whether the degree of tricuspid annular displacement (tricuspid annular plane systolic excursion [TAPSE]) is a useful echo-derived measure of RV function with prognostic significance in pulmonary hypertension.We prospectively studied 63 consecutive patients with pulmonary hypertension who were referred for a clinically indicated right heart catheterization. Patients underwent right heart catheterization immediately followed by transthoracic echocardiogram and TAPSE measurement.In the overall cohort, a TAPSE of less than 1.8 cm was associated with greater RV systolic dysfunction (cardiac index, 1.9 vs. 2.7 L/min/m2; RV % area change, 24 vs. 33%), right heart remodeling (right atrial area index, 17.0 vs. 12.1 cm(2)/m), and RV-left ventricular (LV) disproportion (RV/LV diastolic area, 1.7 vs. 1.2; all p0.001), versus a TAPSE of 1.8 cm or greater. In patients with pulmonary arterial hypertension (PAH; n = 47), survival estimates at 1 and 2 yr were 94 and 88%, respectively, in those with a TAPSE of 1.8 cm or greater versus 60 and 50%, respectively, in subjects with a TAPSE less than 1.8 cm. The unadjusted risk of death (hazard ratio) in patients with a TAPSE less than 1.8 versus 1.8 cm or greater was 5.7 (95% confidence interval, 1.3-24.9; p = 0.02) for the PAH cohort. For every 1-mm decrease in TAPSE, the unadjusted risk of death increased by 17% (hazard ratio, 1.17; 95% confidence interval, 1.05-1.30; p = 0.006), which persisted after adjusting for other echocardiographic and hemodynamic variables and baseline treatment status.TAPSE powerfully reflects RV function and prognosis in PAH.

article i nfo Background:Pixel-basedmultimodality tissuetracking (MTT) isa newnoninvasivemethodfor thequantification of cardiac deformation from cine image of MRI. The aim of this study is to validate bi-ventricular strain measure- ment by MTT compared to strain-encoding (SENC) MRI and harmonic phase (HARP) MRI in pulmonary hyper- tension (PH) patients. Methods:In 45 subjects (30 PH patients and 15 normal subjects), RV and LV peak global longitudinal strains (Ell) were measured from long axis 4 chamber view using MTT. LV peak global circumferential strains (Ecc) by MTT were measured from short axis. For validation, RV and LV Ell by MTT were compared to measures by SENC- MRI from short axis, and LV Ecc by MTT was compared to measures by short axis tagged MRI analysis (HARP). Reproducibility of MTT was also determined. Results: MTT quantified RV Ell correlated closelyto those of SENC (r = 0.72, p b 0.001), with good limits of agree- ment.LVEllquantifiedbyMTTshowedmoderatecorrelationwithSENC(r=0.57,p=0.001),andLVEccbyMTT

Background Left ventricular (LV) diastolic dysfunction is considered to be an important determinant of heart failure with preserved LV ejection fraction (LVEF). Hypertension, diabetes and aging leading to increased aortic stiffness have been related to impaired diastolic function. Novel CMR measures of proximal aortic function have been recently shown to be better markers of vascular aging than conventional measures of arterial stiffness but their relationship to LV diastolic function has not been reported.