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1.
Seung-Pyo Lee Sung-Ji Park Yong-Jin Kim Sung-A Chang Eun-Ah Park Hyung-Kwan Kim Whal Lee Sang-Chol Lee Seung Woo Park Dae-Won Sohn Yeon-Hyeon Choe 《Journal of cardiovascular magnetic resonance》2013,15(1):72
Background
Severe aortic stenosis (AS) patients with late gadolinium enhancement (LGE) on cardiovascular magnetic resonance (CMR) or left ventricular (LV) systolic dysfunction are known to have worse outcome. We aimed to investigate whether LGE on CMR would be useful in early detection of subclinical LV structural and functional derangements in AS patients.Methods
118 patients with moderate to severe AS were prospectively enrolled. Echocardiography and CMR images were taken and the patients were divided into groups according to the presence/absence of LGE and of LV systolic dysfunction (LV ejection fraction (EF) <50%). The stiffness of LV was calculated based on Doppler and CMR measurements.Results
Patients were grouped into either group 1, no LGE and normal LVEF, group 2, LGE but normal LVEF and group 3, LGE with depressed LVEF. There was a significant trend towards increasing LV volumes, worsening of LV diastolic function (E/e’, diastolic elastance), systolic function (end-systolic elastance) and LV hypertrophy between the three groups, which coincided with worsening functional capacity (all p-value < 0.001 for trend). Also, significant differences in the above parameters were noted between group 1 and 2 (E/e’, 14.6 ± 4.3 (mean ± standard deviation) in group 1 vs. 18.2 ± 9.4 in group 2; end-systolic elastance, 3.24 ± 2.31 in group 1 vs. 2.38 ± 1.16 in group 2, all p-value < 0.05). The amount of myocardial fibrosis on CMR correlated with parameters of diastolic (diastolic elastance, Spearman’s ρ = 0.256, p-value = 0.005) and systolic function (end-systolic elastance, Spearman’s ρ = -0.359, p-value < 0.001).Conclusions
These findings demonstrate the usefulness of CMR for early detection of subclinical LV structural and functional deterioration in AS patients. 相似文献2.
Florian Andre Henning Steen Philipp Matheis Maria Westkott Kristin Breuninger Yannick Sander Rebekka Kammerer Christian Galuschky Evangelos Giannitsis Grigorios Korosoglou Hugo A Katus Sebastian J Buss 《Journal of cardiovascular magnetic resonance》2015,17(1)
Background
Assessment of left (LV) ventricular function is one of the most important tasks of cardiovascular magnetic resonance (CMR). Impairment of LV deformation is a strong predictor of cardiovascular outcome in various cardiac diseases like ischemic heart disease or cardiomyopathies. The aim of the study was to provide reference values for myocardial deformation derived from the CMR feature tracking imaging (FTI) algorithm in a reference population of healthy volunteers.Methods
FTI was applied to standard short axis and 2-, 3- and 4-chamber views of vector-ECG gated CMR cine SSFP sequences of 150 strictly selected healthy volunteers (75 male/female) of three age tertiles (mean age 45.8yrs). Global peak and mean radial, circumferential and longitudinal endo- and myocardial systolic strain values as well as early diastolic strain rates were measured using FTI within a standard protocol on a 1.5T whole body MR scanner.Results
Global peak systolic values were 36.3 ± 8.7% for radial, −27.2 ± 4.0% for endocardial circumferential, −21.3 ± 3.3% for myocardial circumferential, −23.4 ± 3.4% for endocardial longitudinal and −21.6 ± 3.2% for myocardial longitudinal strain. Global peak values were -2.1 ± 0.5s−1 for radial, 2.1 ± 0.6s−1 for circumferential endocardial, 1.7 ± 0.5s−1 for circumferential myocardial, 1.8 (1.5-2.2)s−1 for longitudinal endocardial, 1.6 (1.4-2.0)s−1 for longitudinal myocardial early diastolic strain rates. Men showed a higher radial strain than women whereas the circumferential and longitudinal strains were lower resulting in less negative values. Circumferential and longitudinal strain rates were significantly higher in female subjects. Radial strain increased significantly with age whereas the diastolic function measured by the radial, circumferential and longitudinal strain rates showed a decrease.The coefficients of variation determined in ten further subjects, who underwent two CMR examinations within 12 days, were −4.8% for circumferential and −4.5% for longitudinal endocardial mean strains.Conclusions
Myocardial deformation analysis using FTI is a novel technique and robust when applied to standard cine CMR images providing the possibility of a reliable, objective quantification of global LV deformation. Since strain values and strain rates differed partly between genders as well as between age groups, the application of specific reference values as provided by this study is recommendable. 相似文献3.
Dorinna D Mendoza Noel CF Codella Yi Wang Martin R Prince Sonia Sethi Shant J Manoushagian Keigo Kawaji James K Min Troy M LaBounty Richard B Devereux Jonathan W Weinsaft 《Journal of cardiovascular magnetic resonance》2010,12(1):46
Objectives
To examine relationships between severity of echocardiography (echo) -evidenced diastolic dysfunction (DD) and volumetric filling by automated processing of routine cine cardiovascular magnetic resonance (CMR).Background
Cine-CMR provides high-resolution assessment of left ventricular (LV) chamber volumes. Automated segmentation (LV-METRIC) yields LV filling curves by segmenting all short-axis images across all temporal phases. This study used cine-CMR to assess filling changes that occur with progressive DD.Methods
115 post-MI patients underwent CMR and echo within 1 day. LV-METRIC yielded multiple diastolic indices - E:A ratio, peak filling rate (PFR), time to peak filling rate (TPFR), and diastolic volume recovery (DVR80 - proportion of diastole required to recover 80% stroke volume). Echo was the reference for DD.Results
LV-METRIC successfully generated LV filling curves in all patients. CMR indices were reproducible (≤ 1% inter-reader differences) and required minimal processing time (175 ± 34 images/exam, 2:09 ± 0:51 minutes). CMR E:A ratio decreased with grade 1 and increased with grades 2-3 DD. Diastolic filling intervals, measured by DVR80 or TPFR, prolonged with grade 1 and shortened with grade 3 DD, paralleling echo deceleration time (p < 0.001). PFR by CMR increased with DD grade, similar to E/e'' (p < 0.001). Prolonged DVR80 identified 71% of patients with echo-evidenced grade 1 but no patients with grade 3 DD, and stroke-volume adjusted PFR identified 67% with grade 3 but none with grade 1 DD (matched specificity = 83%). The combination of DVR80 and PFR identified 53% of patients with grade 2 DD. Prolonged DVR80 was associated with grade 1 (OR 2.79, CI 1.65-4.05, p = 0.001) with a similar trend for grade 2 (OR 1.35, CI 0.98-1.74, p = 0.06), whereas high PFR was associated with grade 3 (OR 1.14, CI 1.02-1.25, p = 0.02) DD.Conclusions
Automated cine-CMR segmentation can discern LV filling changes that occur with increasing severity of echo-evidenced DD. Impaired relaxation is associated with prolonged filling intervals whereas restrictive filling is characterized by increased filling rates. 相似文献4.
Vincenzo Giglio Paolo Emilio Puddu Giovanni Camastra Stefano Sbarbati Sabino Walter Della Sala Alessandra Ferlini Francesca Gualandi Enzo Ricci Federico Sciarra Gerardo Ansalone Marco Di Gennaro 《Journal of cardiovascular magnetic resonance》2014,16(1):45
Background
This study was designed to assess whether cardiovascular magnetic resonance imaging (CMR) in Duchenne muscular dystrophy carriers (DMDc) may index any cell milieu elements of LV dysfunction and whether this cardiac phenotype may be related to genotype. The null hypothesis was that myocardial fibrosis, assessed by late gadolinium enhancement (LGE), might be similarly accounted for in DMDc and gender and age-matched controls.Methods
Thirty DMDc patients had CMR and genotyping with 37 gender and age-matched controls. Systolic and diastolic LV function was assessed by 2D-echocardiography.Results
Absolute and percent LGE were higher in muscular symptomatic (sym) than asymptomatic (asy) DMDc (1.77 ± 0.27 vs 0.76 ± 0.17 ml; F = 19.6, p < 0.0001 and 1.86 ± 0.26% vs 0.68 ± 0.17%, F = 22.1, p < 0.0001, respectively). There was no correlation between LGE and age. LGE was seen most frequently in segments 5 and 6; segment 5 was involved in all asy-DMDc. Subepicardial LGE predominated, compared to the mid-myocardial one (11 out of 14 DMDc). LGE was absent in the subendocardium. No correlations were seen between genotyping (type of mutation, gene region and protein domain), confined to the exon’s study, and cardiac phenotype.Conclusions
A typical myocardial LGE-pattern location (LV segments 5 and 6) was a common finding in DMDc. LGE was more frequently subepicardial plus midmyocardial in sym-DMDc, with normal LV systolic and diastolic function. No genotype-phenothype correlation was found. 相似文献5.
Toshinari Onishi Samir K Saha Daniel R Ludwig Tetsuari Onishi Josef J Marek Jo?o L Cavalcante Erik B Schelbert David Schwartzman John Gorcsan III 《Journal of cardiovascular magnetic resonance》2013,15(1):95
Background
Analysis of left ventricular (LV) mechanical dyssynchrony may provide incremental prognostic information regarding cardiac resynchronization therapy (CRT) response in addition to QRS width alone. Our objective was to quantify LV dyssynchrony using feature tracking post processing of routine cardiovascular magnetic resonance (CMR) cine acquisitions (FT-CMR) in comparison to speckle tracking echocardiography.Methods
We studied 72 consecutive patients who had both steady-state free precession CMR and echocardiography. Mid-LV short axis CMR cines were analyzed using FT-CMR software and compared with echocardiographic speckle tracking radial dyssynchrony (time difference between the anteroseptal and posterior wall peak strain).Results
Radial dyssynchrony analysis was possible by FT-CMR in all patients, and in 67 (93%) by echocardiography. Dyssynchrony by FT-CMR and speckle tracking showed limits of agreement of strain delays of ± 84 ms. These were large (up to 100% or more) relative to the small mean delays measured in more synchronous patients, but acceptable (mainly <25%) in those with mean delays of >200 ms. Radial dyssynchrony was significantly greater in wide QRS patients than narrow QRS patients by both FT-CMR (radial strain delay 230 ± 94 vs. 77 ± 92* ms) and speckle tracking (radial strain delay 242 ± 101 vs. 75 ± 88* ms, all *p < 0.001).Conclusions
FT-CMR delivered measurements of radial dyssynchrony from CMR cine acquisitions which, at least for the patients with more marked dyssynchrony, showed reasonable agreement with those from speckle tracking echocardiography. The clinical usefulness of the method, for example in predicting prognosis in CRT patients, remains to be investigated. 相似文献6.
7.
Heiner Latus Kerstin Gummel Stefan Rupp Matthias Mueller Christian Jux Gunter Kerst Hakan Akintuerk Juergen Bauer Dietmar Schranz Christian Apitz 《Journal of cardiovascular magnetic resonance》2014,16(1):3
Background
In patients with anomalous left coronary artery from the pulmonary artery (ALCAPA) left ventricular (LV) dilatation and dysfunction evolves due to diminished myocardial perfusion caused by coronary steal phenomenon. Using late gadolinium enhanced cardiovascular magnetic resonance (LGE-CMR) imaging, myocardial scarring has been shown in ALCAPA patients late after repair, however the incidence of scarring before surgery and its impact on postoperative course after surgical repair remained unknown.Methods
8 ALCAPA-patients (mean age 10.0 ± 5.8 months) underwent CMR before and early after (mean 4.9 ± 2.5 months) coronary reimplantation procedures. CMR included functional analysis and LGE for detection of myocardial scars.Results
LV dilatation (mean LVEDVI 171 ± 94 ml/m2) and dysfunction (mean LV-EF 22 ± 10 %) was present in all patients and improved significantly after surgery (mean LVEDV 68 ± 42 ml/m2, p = 0.02; mean LV-EF 58 ± 19 %, p < 0.001). Preoperative CMR revealed myocardial scarring in 2 of the 8 patients and did not predict postoperative course. At follow-up CMR, one LGE-positive patient showed delayed recovery of LV function while myocardial scarring was still present in both patients. In two patients new-onset transmural scarring was found, although functional recovery after operation was sufficient. One of them showed a stenosis of the left coronary artery and required resurgery.Conclusions
Despite diminished myocardial perfusion and severely compromised LV function, myocardial scarring was preoperatively only infrequently present. Improvement of myocardial function was independent of new-onset scarring while the impact of preoperative scarring still needs to be defined. 相似文献8.
Mohammed S M Elbaz Emmeline E Calkoen Jos J M Westenberg Boudewijn P F Lelieveldt Arno A W Roest Rob J van der Geest 《Journal of cardiovascular magnetic resonance》2014,16(1)
Background
LV diastolic vortex formation has been suggested to critically contribute to efficient blood pumping function, while altered vortex formation has been associated with LV pathologies. Therefore, quantitative characterization of vortex flow might provide a novel objective tool for evaluating LV function. The objectives of this study were 1) assess feasibility of vortex flow analysis during both early and late diastolic filling in vivo in normal subjects using 4D Flow cardiovascular magnetic resonance (CMR) with retrospective cardiac gating and 3D vortex core analysis 2) establish normal quantitative parameters characterizing 3D LV vortex flow during both early and late ventricular filling in normal subjects.Methods
With full ethical approval, twenty-four healthy volunteers (mean age: 20±10 years) underwent whole-heart 4D Flow CMR. The Lambda2-method was used to extract 3D LV vortex ring cores from the blood flow velocity field during early (E) and late (A) diastolic filling. The 3D location of the center of vortex ring core was characterized using cylindrical cardiac coordinates (Circumferential, Longitudinal (L), Radial (R)). Comparison between E and A filling was done with a paired T-test. The orientation of the vortex ring core was measured and the ring shape was quantified by the circularity index (CI). Finally, the Spearman’s correlation between the shapes of mitral inflow pattern and formed vortex ring cores was tested.Results
Distinct E- and A-vortex ring cores were observed with centers of A-vortex rings significantly closer to the mitral valve annulus (E-vortex L=0.19±0.04 versus A-vortex L=0.15±0.05; p=0.0001), closer to the ventricle’s long-axis (E-vortex: R=0.27±0.07, A-vortex: R=0.20±0.09, p=0.048) and more elliptical in shape (E-vortex: CI=0.79±0.09, A-vortex: CI=0.57±0.06; <0.001) compared to E-vortex. The circumferential location and orientation relative to LV long-axis for both E- and A-vortex ring cores were similar. Good to strong correlation was found between vortex shape and mitral inflow shape through both the annulus (r=0.66) and leaflet tips (r=0.83).Conclusions
Quantitative characterization and comparison of 3D vortex rings in LV inflow during both early and late diastolic phases is feasible in normal subjects using retrospectively-gated 4D Flow CMR, with distinct differences between early and late diastolic vortex rings.Electronic supplementary material
The online version of this article (doi:10.1186/s12968-014-0078-9) contains supplementary material, which is available to authorized users. 相似文献9.
Alicia M Maceira Carmen Ripoll Juan Cosin-Sales Bego?a Igual Mirella Gavilan Jose Salazar Vicente Belloch Dudley J Pennell 《Journal of cardiovascular magnetic resonance》2014,16(1):26
Background
Cocaine is an addictive, sympathomimetic drug with potentially lethal effects. The prevalence and features of cocaine cardiotoxicity are not well known. We aimed to assess these effects using a comprehensive cardiovascular magnetic resonance (CMR) protocol in a large group of asymptomatic cocaine users.Methods
Consecutive (n = 94, 81 males, 36.6 ±7 years), non-selected, cocaine abusers were recruited and had a medical history, examination, ECG, blood test and CMR. The CMR study included measurement of left and right ventricular (LV, RV) dimensions and ejection fraction (EF), sequences for detection of myocardial oedema and late gadolinium enhancement (LGE). Images were compared to a cohort of healthy controls.Results
Years of regular cocaine use were 13.9 ± 9. When compared to the age-matched healthy cohort, the cocaine abusers had increased LV end-systolic volume, LV mass index and RV end-systolic volume, with decreased LVEF and RVEF. No subject had myocardial oedema, but 30% had myocardial LGE indicating myocardial damage.Conclusions
CMR detected cardiovascular disease in 71% of this cohort of consecutive asymptomatic cocaine abusers and mean duration of abuse was related to probability of LV systolic dysfunction. 相似文献10.
Vincent Wu Janice Y Chyou Sohae Chung Sharath Bhagavatula Leon Axel 《Journal of cardiovascular magnetic resonance》2014,16(1)
Background
Measurement of mitral annulus (MA) dynamics is an important component of the evaluation of left ventricular (LV) diastolic function; MA velocities are commonly measured using tissue Doppler imaging (TDI). This study aimed to examine the clinical potential of a semi-automated cardiovascular magnetic resonance (CMR) technique for quantifying global LV diastolic function, using 3D volume tracking of the MA with conventional cine-CMR images.Methods
124 consecutive patients with normal ejection fraction underwent both clinically indicated transthoracic echocardiography (TTE) and CMR within 2 months. Interpolated 3D reconstruction of the MA over time was performed with semi-automated atrioventricular junction (AVJ) tracking in long-axis cine-CMR images, producing an MA sweep volume over the cardiac cycle. CMR-based diastolic function was evaluated, using the following parameters: peak volume sweep rates in early diastole (PSRE) and atrial systole (PSRA), PSRE/PSRA ratio, deceleration time of sweep volume (DTSV), and 50% diastolic sweep volume recovery time (DSVRT50); these were compared with TTE diastolic measurements.Results
Patients with TTE-based diastolic dysfunction (n = 62) showed significantly different normalized MA sweep volume profiles compared to those with TTE-based normal diastolic function (n = 62), including a lower PSRE (5.25 ± 1.38 s−1 vs. 7.72 ± 1.7 s−1), a higher PSRA (6.56 ± 1.99 s−1 vs. 4.67 ± 1.38 s−1), a lower PSRE/PSRA ratio (0.9 ± 0.44 vs. 1.82 ± 0.69), a longer DTSV (144 ± 55 ms vs. 96 ± 37 ms), and a longer DSVRT50 (25.0 ± 11.0% vs. 15.6 ± 4.0%) (all p < 0.05). CMR diastolic parameters were independent predictors of TTE-based diastolic dysfunction after adjusting for left ventricular hypertrophy, hypertension, and coronary artery disease. Good correlations were observed between CMR PSRE/PSRA and early-to-late diastolic annular velocity ratios (e′/a′) measured by TDI (r = 0.756 to 0.828, p < 0.001).Conclusions
3D MA sweep volumes generated by semi-automated AVJ tracking in routinely acquired CMR images yielded diastolic parameters that were effective in identifying patients with diastolic dysfunction when correlated with TTE-based variables. 相似文献11.
Andris H Ellims Leah M Iles Liang-han Ling James L Hare David M Kaye Andrew J Taylor 《Journal of cardiovascular magnetic resonance》2012,14(1):76
Background
The presence of myocardial fibrosis is associated with worse clinical outcomes in hypertrophic cardiomyopathy (HCM). Cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) sequences can detect regional, but not diffuse myocardial fibrosis. Post-contrast T1 mapping is an emerging CMR technique that may enable the non-invasive evaluation of diffuse myocardial fibrosis in HCM. The purpose of this study was to non-invasively detect and quantify diffuse myocardial fibrosis in HCM with CMR and examine its relationship to diastolic performance.Methods
We performed CMR on 76 patients - 51 with asymmetric septal hypertrophy due to HCM and 25 healthy controls. Left ventricular (LV) morphology, function and distribution of regional myocardial fibrosis were evaluated with cine imaging and LGE. A CMR T1 mapping sequence determined the post-contrast myocardial T1 time as an index of diffuse myocardial fibrosis. Diastolic function was assessed by transthoracic echocardiography.Results
Regional myocardial fibrosis was observed in 84% of the HCM group. Post-contrast myocardial T1 time was significantly shorter in patients with HCM compared to controls, consistent with diffuse myocardial fibrosis (498 ± 80 ms vs. 561 ± 47 ms, p < 0.001). In HCM patients, post-contrast myocardial T1 time correlated with mean E/e’ (r = −0.48, p < 0.001).Conclusions
Patients with HCM have shorter post-contrast myocardial T1 times, consistent with diffuse myocardial fibrosis, which correlate with estimated LV filling pressure, suggesting a mechanistic link between diffuse myocardial fibrosis and abnormal diastolic function in HCM. 相似文献12.
Wei Feng Hosakote Nagaraj Himanshu Gupta Steven G Lloyd Inmaculada Aban Gilbert J Perry David A Calhoun Louis J Dell'Italia Thomas S Denney Jr 《Journal of cardiovascular magnetic resonance》2009,11(1):30
Background
Although cardiovascular magnetic resonance (CMR) is frequently performed to measure accurate LV volumes and ejection fractions, LV volume-time curves (VTC) derived ejection and filling rates are not routinely calculated due to lack of robust LV segmentation techniques. VTC derived peak filling rates can be used to accurately assess LV diastolic function, an important clinical parameter. We developed a novel geometry-independent dual-contour propagation technique, making use of LV endocardial contours manually drawn at end systole and end diastole, to compute VTC and measured LV ejection and filling rates in hypertensive patients and normal volunteers.Methods
39 normal volunteers and 49 hypertensive patients underwent CMR. LV contours were manually drawn on all time frames in 18 normal volunteers. The dual-contour propagation algorithm was used to propagate contours throughout the cardiac cycle. The results were compared to those obtained with single-contour propagation (using either end-diastolic or end-systolic contours) and commercially available software. We then used the dual-contour propagation technique to measure peak ejection rate (PER) and peak early diastolic and late diastolic filling rates (ePFR and aPFR) in all normal volunteers and hypertensive patients.Results
Compared to single-contour propagation methods and the commercial method, VTC by dual-contour propagation showed significantly better agreement with manually-derived VTC. Ejection and filling rates by dual-contour propagation agreed with manual (dual-contour – manual PER: -0.12 ± 0.08; ePFR: -0.07 ± 0.07; aPFR: 0.06 ± 0.03 EDV/s, all P = NS). However, the time for the manual method was ~4 hours per study versus ~7 minutes for dual-contour propagation. LV systolic function measured by LVEF and PER did not differ between normal volunteers and hypertensive patients. However, ePFR was lower in hypertensive patients vs. normal volunteers, while aPFR was higher, indicative of altered diastolic filling rates in hypertensive patients.Conclusion
Dual-propagated contours can accurately measure both systolic and diastolic volumetric indices that can be applied in a routine clinical CMR environment. With dual-contour propagation, the user interaction that is routinely performed to measure LVEF is leveraged to obtain additional clinically relevant parameters. 相似文献13.
Ning Hua Zhongjing Chen Alkystis Phinikaridou Tuan Pham Ye Qiao Michael P LaValley Sherman J Bigornia Megan R Ruth Caroline M Apovian Frederick L Ruberg James A Hamilton 《Journal of cardiovascular magnetic resonance》2014,16(1):37
Background
Although increased volume of pericardial fat has been associated with decreased cardiac function, it is unclear whether this association is mediated by systemic overall obesity or direct regional fat interactions. We hypothesized that if local effects dominate, left ventricular (LV) function would be most strongly associated with pericardial fat that surrounds the left rather than the right ventricle (RV).Methods
Female obese subjects (n = 60) had cardiovascular magnetic resonance (CMR) scans to obtain measures of LV function and pericardial fat volumes. LV function was obtained using the cine steady state free precession imaging in short axis orientation. The amount of pericardial fat was determined volumetrically by the cardiac gated T1 black blood imaging and normalized to body surface area.Results
In this study cohort, LV fat correlated with several LV hemodynamic measurements including cardiac output (r = -0.41, p = 0.001) and stroke volume (r = -0.26, p = 0.05), as well as diastolic functional parameters including peak-early-filling rate (r = -0.38, p = 0.01), early late filling ratio (r = -0.34, p = 0.03), and time to peak-early-filling (r = 0.34, p = 0.03). These correlations remained significant even after adjusting for the body mass index and the blood pressure. However, similar correlations became weakened or even disappeared between RV fat and LV function. LV function was not correlated with systemic plasma factors, such as C-reactive protein (CRP), B-type natriuretic peptide (BNP), Interleukin-6 (IL-6), resistin and adiponectin (all p > 0.05).Conclusions
LV hemodynamic and diastolic function was associated more with LV fat as compared to RV or total pericardial fat, but not with systemic inflammatory markers or adipokines. The correlations between LV function and pericardial fat remained significant even after adjusting for systemic factors. These findings suggest a site-specific influence of pericardial fat on LV function, which could imply local secretion of molecules into the underlying tissue or an anatomic effect, both mechanisms meriting future evaluation. 相似文献14.
Kristofer Nyman Marit Granér Markku O Pentik?inen Jesper Lundbom Antti Hakkarainen Reijo Sirén Markku S Nieminen Marja-Riitta Taskinen Nina Lundbom Kirsi Lauerma 《Journal of cardiovascular magnetic resonance》2013,15(1):103
Background
Ectopic accumulation of fat accompanies visceral obesity with detrimental effects. Lipid oversupply to cardiomyocytes leads to cardiac steatosis, and in animal studies lipotoxicity has been associated with impaired left ventricular (LV) function. In humans, studies have yielded inconclusive results. The aim of the study was to evaluate the role of epicardial, pericardial and myocardial fat depots on LV structure and function in male subjects with metabolic syndrome (MetS).Methods
A study population of 37 men with MetS and 38 men without MetS underwent cardiovascular magnetic resonance and proton magnetic spectroscopy at 1.5 T to assess LV function, epicardial and pericardial fat area and myocardial triglyceride (TG) content.Results
All three fat deposits were greater in the MetS than in the control group (p <0.001). LV diastolic dysfunction was associated with MetS as measured by absolute (471 mL/s vs. 667 mL/s, p = 0.002) and normalized (3.37 s-1 vs. 3.75 s-1, p = 0.02) LV early diastolic peak filling rate and the ratio of early diastole (68% vs. 78%, p = 0.001). The amount of epicardial and pericardial fat correlated inversely with LV diastolic function. However, myocardial TG content was not independently associated with LV diastolic dysfunction.Conclusions
In MetS, accumulation of epicardial and pericardial fat is linked to the severity of structural and functional alterations of the heart. The role of increased intramyocardial TG in MetS is more complex and merits further study. 相似文献15.
Iris K Rüssel Wessel P Brouwer Tjeerd Germans Paul Knaapen Tim J Marcus Jolanda van der Velden Marco JW G?tte Albert C van Rossum 《Journal of cardiovascular magnetic resonance》2011,13(1):3
Background
Increased left ventricular (LV) torsion has been observed in patients with manifest familial hypertrophic cardiomyopathy (HCM), and is thought to be caused by subendocardial dysfunction. We hypothesize that increased LV torsion is already present in healthy mutation carriers with normal wall thickness.Methods
Seventeen carriers with an LV wall thickness <10 mm, and seventeen age and gender matched controls had cardiovascular magnetic resonance (CMR) cine imaging and tissue tagging. LV volumes and mass were calculated from the cine images. LV torsion, torsion rate, endocardial circumferential strain and torsion-to-endocardial-circumferential-shortening (TECS) ratio, which reflects the transmural distribution in contractile function, were determined using tissue tagging.Results
LV volumes, mass and circumferential strain were comparable between groups, whereas LV ejection fraction, torsion and TECS-ratio were increased in carriers compared to controls (63 ± 3% vs. 60 ± 3%, p = 0.04, 10.1 ± 2.5° vs. 7.7 ± 1.2°, p = 0.001, and 0.52 ± 0.14°/% vs. 0.42 ± 0.10°/%, p = 0.02, respectively).Conclusions
Carriers with normal wall thickness display increased LV torsion and TECS-ratio with respect to controls, which might be due to subendocardial myocardial dysfunction. As similar abnormalities are observed in patients with manifest HCM, the changes in healthy carriers may be target for clinical intervention to delay or prevent the onset of hypertrophy. 相似文献16.
Ikechukwu U. Okafor Arvind Santhanakrishnan Brandon D. Chaffins Lucia Mirabella John N. Oshinski Ajit P. Yoganathan 《Journal of cardiovascular magnetic resonance》2015,17(1)
Background
The development of clinically applicable fluid-structure interaction (FSI) models of the left heart is inherently challenging when using in vivo cardiovascular magnetic resonance (CMR) data for validation, due to the lack of a well-controlled system where detailed measurements of the ventricular wall motion and flow field are available a priori. The purpose of this study was to (a) develop a clinically relevant, CMR-compatible left heart physical model; and (b) compare the left ventricular (LV) volume reconstructions and hemodynamic data obtained using CMR to laboratory-based experimental modalities.Methods
The LV was constructed from optically clear flexible silicone rubber. The geometry was based off a healthy patient’s LV geometry during peak systole. The LV phantom was attached to a left heart simulator consisting of an aorta, atrium, and systemic resistance and compliance elements. Experiments were conducted for heart rate of 70 bpm. Wall motion measurements were obtained using high speed stereo-photogrammetry (SP) and cine-CMR, while flow field measurements were obtained using digital particle image velocimetry (DPIV) and phase-contrast magnetic resonance (PC-CMR).Results
The model reproduced physiologically accurate hemodynamics (aortic pressure = 120/80 mmHg; cardiac output = 3.5 L/min). DPIV and PC-CMR results of the center plane flow within the ventricle matched, both qualitatively and quantitatively, with flow from the atrium into the LV having a velocity of about 1.15 m/s for both modalities. The normalized LV volume through the cardiac cycle computed from CMR data matched closely to that from SP. The mean difference between CMR and SP was 5.5 ± 3.7 %.Conclusions
The model presented here can thus be used for the purposes of: (a) acquiring CMR data for validation of FSI simulations, (b) determining accuracy of cine-CMR reconstruction methods, and (c) conducting investigations of the effects of altering anatomical variables on LV function under normal and disease conditions. 相似文献17.
Verena Hoerr Nina Nagelmann Arno Nauerth Michael T Kuhlmann J?rg Stypmann Cornelius Faber 《Journal of cardiovascular magnetic resonance》2013,15(1):59
Background
To overcome flow and electrocardiogram-trigger artifacts in cardiovascular magnetic resonance (CMR), we have implemented a cardiac and respiratory self-gated cine ultra-short echo time (UTE) sequence. We have assessed its performance in healthy mice by comparing the results with those obtained with a self-gated cine fast low angle shot (FLASH) sequence and with echocardiography.Methods
2D self-gated cine UTE (TE/TR = 314 μs/6.2 ms, resolution: 129 × 129 μm, scan time per slice: 5 min 5 sec) and self-gated cine FLASH (TE/TR = 3 ms/6.2 ms, resolution: 129 × 129 μm, scan time per slice: 4 min 49 sec) images were acquired at 9.4 T. Volume of the left and right ventricular (LV, RV) myocardium as well as the end-diastolic and -systolic volume was segmented manually in MR images and myocardial mass, stroke volume (SV), ejection fraction (EF) and cardiac output (CO) were determined. Statistical differences were analyzed by using Student t test and Bland-Altman analyses.Results
Self-gated cine UTE provided high quality images with high contrast-to-noise ratio (CNR) also for the RV myocardium (CNRblood-myocardium = 25.5 ± 7.8). Compared to cine FLASH, susceptibility, motion, and flow artifacts were considerably reduced due to the short TE of 314 μs. The aortic valve was clearly discernible over the entire cardiac cycle. Myocardial mass, SV, EF and CO determined by self-gated UTE were identical to the values measured with self-gated FLASH and showed good agreement to the results obtained by echocardiography.Conclusions
Self-gated UTE allows for robust measurement of cardiac parameters of diagnostic interest. Image quality is superior to self-gated FLASH, rendering the method a powerful alternative for the assessment of cardiac function at high magnetic fields. 相似文献18.
Xiomara Q Rosales Sean J Moser Tam Tran Beth McCarthy Nicholas Dunn Philip Habib Orlando P Simonetti Jerry R Mendell Subha V Raman 《Journal of cardiovascular magnetic resonance》2011,13(1):39
Background
Limb girdle muscular dystrophies (LGMD) are inclusive of 7 autosomal dominant and 14 autosomal recessive disorders featuring progressive muscle weakness and atrophy. Studies of cardiac function have not yet been well-defined in deficiencies of dysferlin (LGMD2B) and fukutin related protein (LGMD2I). In this study of patients with these two forms of limb girdle muscular dystrophy, cardiovascular magnetic resonance (CMR) was used to more specifically define markers of cardiomyopathy including systolic dysfunction, myocardial fibrosis, and diastolic dysfunction.Methods
Consecutive patients with genetically-proven LGMD types 2I (n = 7) and 2B (n = 9) and 8 control subjects were enrolled. All subjects underwent cardiac magnetic resonance (CMR) on a standard 1.5 Tesla clinical scanner with cine imaging for left ventricular (LV) volume and ejection fraction (EF) measurement, vector velocity analysis of cine data to calculate myocardial strain, and late post-gadolinium enhancement imaging (LGE) to assess for myocardial fibrosis.Results
Sixteen LGMD patients (7 LGMD2I, 9 LGMD2B), and 8 control subjects completed CMR. All but one patient had normal LV size and systolic function; one (type 2I) had severe dilated cardiomyopathy. Of 15 LGMD patients with normal systolic function, LGE imaging revealed focal myocardial fibrosis in 7 (47%). Peak systolic circumferential strain rates were similar in patients vs. controls: εendo was -23.8 ± 8.5vs. -23.9 ± 4.2%, εepi was -11.5 ± 1.7% vs. -10.1 ± 4.2% (p = NS for all). Five of 7 LGE-positive patients had grade I diastolic dysfunction [2I (n = 2), 2B (n = 3)]. that was not present in any LGE-negative patients or controls.Conclusions
LGMD2I and LGMD2B generally result in mild structural and functional cardiac abnormalities, though severe dilated cardiomyopathy may occur. Long-term studies are warranted to evaluate the prognostic significance of subclinical fibrosis detected by CMR in these patients. 相似文献19.
Francisco Contijoch Walter R. T. Witschey Kelly Rogers Hannah Rears Michael Hansen Paul Yushkevich Joseph Gorman III Robert C. Gorman Yuchi Han 《Journal of cardiovascular magnetic resonance》2015,17(1)
Background
Data obtained during arrhythmia is retained in real-time cardiovascular magnetic resonance (rt-CMR), but there is limited and inconsistent evidence to show that rt-CMR can accurately assess beat-to-beat variation in left ventricular (LV) function or during an arrhythmia.Methods
Multi-slice, short axis cine and real-time golden-angle radial CMR data was collected in 22 clinical patients (18 in sinus rhythm and 4 patients with arrhythmia). A user-initialized active contour segmentation (ACS) software was validated via comparison to manual segmentation on clinically accepted software. For each image in the 2D acquisitions, slice volume was calculated and global LV volumes were estimated via summation across the LV using multiple slices. Real-time imaging data was reconstructed using different image exposure times and frame rates to evaluate the effect of temporal resolution on measured function in each slice via ACS. Finally, global volumetric function of ectopic and non-ectopic beats was measured using ACS in patients with arrhythmias.Results
ACS provides global LV volume measurements that are not significantly different from manual quantification of retrospectively gated cine images in sinus rhythm patients. With an exposure time of 95.2 ms and a frame rate of > 89 frames per second, golden-angle real-time imaging accurately captures hemodynamic function over a range of patient heart rates. In four patients with frequent ectopic contractions, initial quantification of the impact of ectopic beats on hemodynamic function was demonstrated.Conclusion
User-initialized active contours and golden-angle real-time radial CMR can be used to determine time-varying LV function in patients. These methods will be very useful for the assessment of LV function in patients with frequent arrhythmias. 相似文献20.
Stéphanie Seldrum Sophie Pierard Stéphane Moniotte Christiane Vermeylen David Vancraeynest Agnès Pasquet Jean-Louis Vanoverschelde Bernhard L Gerber 《Journal of cardiovascular magnetic resonance》2011,13(1):23