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ObjectiveTo investigate whether sphericity volume index (SVI), an indicator of left ventricular (LV) remodelling, predicts incident cardiovascular events (coronary heart disease, CHD; all cardiovascular disease, CVD; heart failure, HF; atrial fibrillation, AF) over 10 years of follow-up in a multiethnic population (Multi-Ethnic Study of Atherosclerosis).Methods5004 participants free of known CVD had magnetic resonance imaging (MRI) in 2000–2002. Cine images were analysed to compute, equivalent to LV volume/volume of sphere with length of LV as the diameter. The highest (greatest sphericity) and lowest (lowest sphericity) quintiles of SVI were compared against the reference group (2–4 quintiles combined). Risk-factor adjusted hazard's ratio (HR) from Cox regression assessed the predictive performance of SVI at end-diastole (ED) and end-systole (ES) to predict incident outcomes over 10 years in retrospective interpretation of prospective data.ResultsAt baseline, participants were aged 61±10 years; 52% men and 39%/13%/26%/22% Cauc/Chinese/Afr-Amer/Hispanic. Low sphericity was associated with higher Framingham CVD risk, greater coronary calcium score and higher N-terminal pro-brain natriuretic peptide (NT-proBNP); while increased sphericity was associated with higher NT-proBNP and lower ejection fraction. Low sphericity predicted incident CHD (HR: 1.48, 1.55–2.59 at ED) and CVD (HR: 1.82, 1.47–2.27 at ED). However, both low (HR: 1.81, 1.20–2.73 at ES) and high (HR: 2.21, 1.41–3.46 at ES) sphericity predicted incident HF. High sphericity also predicted AF.ConclusionsIn a multiethnic population free of CVD at baseline, lowest sphericity was a predictor of incident CHD, CVD and HF over a 10-year follow-up period. Extreme sphericity was a strong predictor of incident HF and AF. SVI improved risk prediction models beyond established risk factors only for HF, but not for all CVD or CHD.

Cardiovascular magnetic resonance (CMR) is currently the gold standard for assessing both global and regional myocardial function. New tools for quantifying regional function have been recently developed to characterize early myocardial dysfunction in order to improve the identification and management of individuals at risk for heart failure. Of particular interest is CMR myocardial tagging, a non-invasive technique for assessing regional function that provides a detailed and comprehensive examination of intra-myocardial motion and deformation. Given the current advances in gradient technology, image reconstruction techniques, and data analysis algorithms, CMR myocardial tagging has become the reference modality for evaluating multidimensional strain evolution in the human heart. This review presents an in depth discussion on the current clinical applications of CMR myocardial tagging and the increasingly important role of this technique for assessing subclinical myocardial dysfunction in the setting of a wide variety of myocardial disease processes.

Peripheral artery disease (PAD) is important to public health as a major contributor to cardiovascular morbidity and mortality. Recent developments in magnetic resonance imaging (MRI) techniques permit improved assessment of PAD anatomy and physiology, and may serve as surrogate end points after proangiogenic therapies. The PACE study is a randomized, double-blind, placebo-controlled clinical trial designed to assess the physiologic impact and potential clinical efficacy of autologous bone marrow–derived ALDHbr stem cells. The primary MRI end points of the study are as follows: (1) total collateral count, (2) calf muscle plasma volume (a measure of capillary perfusion) by dynamic contrast-enhanced MRI, and (3) peak hyperemic popliteal flow by phase-contrast MRI (PC-MRI). The interreader and intrareader and test-retest results demonstrated good-to-excellent reproducibility (interclass correlation coefficient range 0.61-0.98) for all magnetic resonance measures. The PAD participants (n=82) had lower capillary perfusion measured by calf muscle plasma volume (3.8% vs 5.6%) and peak hyperemic popliteal flow (4.1 vs 13.5mL/s) as compared with the healthy participants (n=16), with a significant level of collateralization. Reproducibility of the MRI primary end points in PACE was very good to excellent. The PAD participants exhibited decreased calf muscle capillary perfusion as well as arterial flow reserve when compared with healthy participants. The MRI tools used in PACE may advance PAD science by enabling accurate measurement of PAD microvascular anatomy and perfusion before and after stem cell or other PAD therapies.

Clinical studies implementing late gadolinium-enhanced (LGE) cardiovascular magnetic resonance (CMR) studies suggest that the peri-infarct zone (PIZ) contains a mixture of viable and non-viable myocytes, and is associated with greater susceptibility to ventricular tachycardia induction and adverse cardiac outcomes. However, CMR data assessing the temporal formation and functional remodeling characteristics of this complex region are limited. We intended to characterize early temporal changes in scar morphology and regional function in the PIZ. CMR studies were performed at six time points up to 90 days after induction of myocardial infarction (MI) in eight minipigs with reperfused, anterior-septal infarcts. Custom signal density threshold algorithms, based on the remote myocardium, were applied to define the infarct core and PIZ region for each time point. After the initial post-MI edema subsided, the PIZ decreased by 54% from day 10 to day 90 (p = 0.04). The size of infarct scar expanded by 14% and thinned by 56% from day 3 to 12 weeks (p = 0.004 and p < 0.001, respectively). LVEDV increased from 34.7. ± 2.2 ml to 47.8 ± 3.0 ml (day3 and week12, respectively; p < 0.001). At 30 days post-MI, regional circumferential strain was increased between the infarct scar and the PIZ (-2.1 ± 0.6 and -6.8 ± 0.9, respectively;* p < 0.05). The PIZ is dynamic and decreases in mass following reperfused MI. Tensile forces in the PIZ undergo changes following MI. Remodeling characteristics of the PIZ may provide mechanistic insights into the development of life-threatening arrhythmias and sudden cardiac death post-MI.

In an international study, the authors evaluated the diagnostic performance of coronary angiography by means of 64-row multidetector computed tomography (CT). The technique accurately identified obstructive coronary lesions, but the positive and negative predictive values were inadequate for this technology to replace conventional coronary angiography with the use of contrast medium. In this study, coronary angiography by means of 64-row multidetector computed tomography (CT) accurately identified obstructive coronary lesions, but the positive and negative predictive values were inadequate for this technology to replace conventional coronary angiography. Coronary artery disease is the leading cause of death in the United States. 1 In symptomatic patients, diagnosis of the presence and severity of coronary artery disease is critical for determining appropriate clinical management. 2 , 3 Indirect evaluation of coronary stenosis, such as through stress testing, has limited diagnostic ability as compared with direct conventional coronary angiography. 4 , 5 Conventional coronary angiography reveals the extent, location, and severity of coronary obstructive lesions, which are potent predictors of outcome, 2 , 3 , 6 , 7 and identifies high-risk patients who may benefit from revascularization. 3 , 6 , 8 – 11 Thus, invasive coronary angiography, despite the associated risks, remains the . . .

In a population-based study, emphysema was quantified by computed tomography, pulmonary function was assessed by spirometry, and cardiac volumes and function were measured by magnetic resonance imaging. Both percent emphysema and the severity of airflow obstruction were linearly related to reductions in left ventricular end-diastolic volume, stroke volume, and cardiac output. These effects were more pronounced among smokers. In a population-based study, emphysema and the severity of airflow obstruction were linearly related to reductions in left ventricular end-diastolic volume, stroke volume, and cardiac output. Chronic obstructive pulmonary disease (COPD), defined as airflow obstruction that is not fully reversible, 1 is currently the fourth leading cause of death in the United States. 2 COPD overlaps partially with emphysema, which is characterized by the destruction of alveolar walls and the permanent enlargement of air spaces distal to the terminal bronchioles. 1 , 3 Cor pulmonale, which can occur in very severe COPD, is characterized by elevated pulmonary vascular resistance and right heart failure, with associated reductions in left ventricular filling, left ventricular stroke volume, and cardiac output, although left ventricular ejection fraction is generally preserved. 4 – 7 This disorder may occur . . .

•Valve calcium progression and heart failure risk was assessed in a diverse cohort.•Progression of valve calcification was associated with increased heart failure risk.•Association seen for heart failure with preserved but not reduced ejection fraction.•This was independent of interim coronary heart disease & atrial fibrillation events. Heart failure (HF) is a leading cause of morbidity. Strategies for preventing HF are paramount. Prevalent extracoronary calcification is associated with HF risk but less is known about progression of mitral annular (MAC) and aortic valve calcification (AVC) and HF risk. Progression of valvular calcification (VC) [interval change of >0 units/yr] was assessed by 2 cardiac computed tomography scans over a median of 2.4 years. We used Cox regression to determine the risk of adjudicated HF and linear mixed effects models to determine 10-year change in left ventricular (LV) parameters measured by cardiac magnetic resonance imaging associated with VC progression. We studied 5,591 MESA participants free of baseline cardiovascular disease. Mean ± SD age was 62 ± 10 years; 53% women; 83% had no VC progression, 15% progressed at 1 site (AVC or MAC) and 3% at both sites. There were 251 incident HF over 15 years. After adjusting for cardiovascular risk factors, the hazard ratios (95% confidence interval) of HF associated with VC progression at 1 and 2 sites were 1.62 (1.21 to 2.17) and 1.88 (1.14 to 3.09), respectively, compared with no progression (p-for-trend <0.001). Hazard ratios were higher for HFpEF (2.52 [1.63 to 3.90] and 2.49 [1.19 to 5.25]) but nonsignificant for HFrEF. Both AVC (1.61 [1.19 to 2.19]) and MAC (1.50 [1.09 to 2.07]) progression were associated with HF. VC was associated with worsening of some LV parameters over 10 years. In conclusion, VC progression was associated with increased risk of HF and change in LV function. Interventions targeted at reducing VC progression may also impact HF risk, particularly HFpEF.

Left ventricular mass is a strong predictor of cardiovascular disease (CVD), and magnetic resonance imaging (MRI) of the heart is a standard of reference for left ventricular mass measurement. Ethnicity is believed to affect electrocardiographic (ECG) performance. We evaluated the diagnostic and prognostic performance of ECG for left ventricular hypertrophy (LVH) as defined by MRI in relationship to ethnicity. Data were analyzed from 4,967 participants (48% men, mean age 62 ± 10 years; 39% white, 13% Chinese, 26% African American, 22% Hispanic) enrolled in the Multi-Ethic Study of Atherosclerosis (MESA) who were followed for a median of 4.8 years for incident CVD. Thirteen traditional ECG-LVH criteria were assessed, and showed overall and ethnicity-specific low sensitivity (10%-26%) and high specificity (88%-99%) in diagnosing MRI-defined LVH. Ten of 13 ECG-LVH criteria showed superior sensitivity and diagnostic performance in African Americans as compared with whites ( P = .02-.001). The sum of amplitudes of S wave in V 1, S wave in V 2, and R wave in V 5 (a MESA-specific ECG-LVH criterion) offered higher sensitivity (40.4%) compared with prior ECG-LVH criteria while maintaining good specificity (90%) and diagnostic performance (receiver operating characteristic area = 0.65). In fully adjusted models, only the MESA-specific ECG-LVH criterion, Romhilt-Estes score, Framingham score, Cornell voltage, Cornell duration product, and Framingham-adjusted Cornell voltage predicted increased CVD risk ( P < .05). Electrocardiography has low sensitivity but high specificity for detecting MRI-defined LVH. The performance of ECG for LVH detection varies by ethnicity, with African Americans showing higher sensitivity and overall performance compared with other ethnic groups.

Myocardial late gadolinium enhancement was originally validated using higher than label-recommended doses of gadolinium chelate. The objective of this study was to evaluate available evidence for various gadolinium dosing regimens used for CMR. The relationship of gadolinium dose warnings (due to nephrogenic systemic fibrosis) announced in 2008 to gadolinium dosing regimens was also examined. We conducted a meta-analysis of peer reviewed publications from January, 2004 to December, 2010. Major subject search headings (MeSh) terms from the National Library of Medicine's PubMed were: contrast media, gadolinium, heart, magnetic resonance imaging; searches were limited to human studies with abstracts published in English. Case reports, review articles, editorials, MRA related papers and all reports that did not indicate gadolinium type or weight-based dose were excluded. For all included references, full text was available to determine the total administered gadolinium dose on a per kg basis. Average and median dose values were weighted by the number of subjects in each study. 399 publications were identified in PubMed; 233 studies matched the inclusion criteria, encompassing 19,934 patients with mean age 54.2 ± 11.4 (range 9.3 to 76 years). 34 trials were related to perfusion testing and 199 to myocardial late gadolinium enhancement. In 2004, the weighted-median and weighted-mean contrast dose were 0.15 and 0.16 ± 0.06 mmol/kg, respectively. Median contrast doses for 2005-2010 were: 0.2 mmol/kg for all years, respectively. Mean contrast doses for the years 2005-2010 were: 0.19 ± 0.03, 0.18 ± 0.04, 0.18 ± 0.10, 0.18 ± 0.03, 0.18 ± 0.04 and 0.18 ± 0.04 mmol/kg, respectively (p for trend, NS). Gadopentetate dimeglumine was the most frequent gadolinium type [114 (48.9%) studies]. No change in mean gadolinium dose was present before, versus after the Food and Drug Administration (FDA) black box warning (p > 0.05). Three multi-center dose ranging trials have been published for cardiac MRI applications. CMR studies in the peer-reviewed published literature routinely use higher gadolinium doses than regulatory agencies indicated in the package leaflet. Clinical trials should be supported to determine the appropriate doses of gadolinium for CMR studies.

Previous research suggests that elevated pulse pressure (PP) is a risk factor for atrial fibrillation (AF) independently of mean arterial pressure (MAP). PP may serve as an indirect measure of aortic stiffness (reduced distensibility), but whether directly measured aortic distensibility is related to risk for AF has not yet been studied. This analysis included 6,630 participants aged 45 to 84 years from the Multi-Ethnic Study of Atherosclerosis. At baseline, blood pressure and other relevant covariates were measured using standardized protocols. Magnetic resonance imaging–based aortic distensibility was measured in 3,441 participants. Incident AF was identified from hospitalization discharge codes and Medicare claims. Multivariate Cox models were used to estimate the association of blood pressure components and aortic distensibility with AF risk. During a mean follow-up of 7.8 years, 307 AF events (137 among those with aortic distensibility measurements) were identified. In multivariate-adjusted models simultaneously including MAP and PP, each 1-SD increase in PP was associated with a 29% increased risk of AF (95% confidence interval 5% to 59%, p = 0.02), with MAP not being associated with increased AF risk. Overall, aortic distensibility was not consistently associated with AF risk: after removing outliers, each 1-SD increase in aortic distensibility was associated with a 9% increased risk of AF (95% confidence interval −22% to 51%, p = 0.63). In conclusion, in this large community-based cohort, we found that PP, but not MAP or aortic distensibility, was a significant risk factor for AF, emphasizing the importance of PP when assessing the risk for developing AF. Our results cast doubt on the clinical utility of aortic distensibility as a predictor for the development of AF.