Shape Of Ventricle Research Articles

Correcting motion in multiplanar cardiac magnetic resonance images.

BackgroundMisalignment in cardiac magnetic resonance (CMR) images can adversely affect three-dimensional left ventricle modelling and downstream quantitative analysis. Currently, there are two types of approaches for dealing with realignment and motion distortion problems, one image based and the other geometry based. Image-based approaches are limited by the inherent non-homogeneity and anisotropy of CMR images. Geometry-based approaches rely on idealized models and over-simplified assumptions. This study was motivated by the need for a robust and effective approach for correcting motion related distortions due to misalignment in CMR images.MethodsA cine cardiac magnetic resonance image sequence was acquired using our routine clinical imaging protocol. The left ventricular endocardium was delineated manually with software assistance on all long and short-axis images. Long and short-axis contours were projected onto a patient-based coordinate system and then realigned using iterative registration. The realigned contour points were used to reconstruct the shape of the left ventricle for quantitative validation.ResultsThe method was tested on five myocardial infarction patients whose images showed substantial misalignment. Realignment time was about 16 seconds per case, using a 2.5 GHz CPU desktop with obvious elimination of the distortion in the reconstructed model. Using the long-axis contour as a reference in evaluating the reconstructed models, it was apparent that the models with realigned contours had better accuracy than the non-realigned ones.ConclusionThis study presents a novel, geometry-based method for correcting motion distortions in CMR images. The method incorporates (1) manual delineation, (2) registration based on a generalized, iterative closest point algorithm, and (3) reconstruction of the shape of the left ventricle for quantitative validation. The effectiveness of our approach is corroborated both visually and by quantitative assessment. We envision the use of our method in current clinical practice as a means of improving accuracy in the evaluation of cardiac function.

Subclinical Right Ventricular Dysfunction by Strain Analysis

The peculiar shape of the right ventricle (RV), its position within the chest, and the thinness of its free wall have always represented a formidable challenge for the assessment of RV size and function by conventional 2-dimensional echocardiography. Over time, a large number of 2D echocardiography and Doppler parameters have been proposed to describe RV geometry and function.1,2 However, most of them are limited by geometric assumptions about RV shape, load dependency, or suboptimal reproducibility, resulting in a limited contribution of conventional echocardiography to the understanding of the role played by the RV in many clinical conditions. See Article by Mukherjee et al In the last decade, the advent of 2D speckle-tracking echocardiography (2DSTE) has fueled the application of strain imaging to measure the RV myocardial deformation, particularly for an early detection of subclinical myocardial dysfunction, when global ventricular function indices are still normal. The possibility to derive strain parameters from conventional gray-scale images with excellent reproducibility and the relative ease of use of the technique have encouraged researchers to apply 2DSTE for elucidating the extent of RV involvement in a wide variety of cardiac and noncardiac conditions. A PubMed search found >800 articles published on RV strain imaging by echocardiography since 2008. In this issue of Circulation: Cardiovascular Imaging , Mukherjee et al3 from the Johns Hopkins University School of Medicine report on the ability of 2DSTE longitudinal strain to detect occult abnormalities in regional and global myocardial function of RV free wall in patients with systemic sclerosis (SSc). Conventional 2DE parameters of RV function (eg, tricuspid annular plane systolic excursion and fractional area change) were similar in patients with SSc versus age- and sex-matched controls, whereas RV free wall …

Clinical, neuroradiological and molecular characterization of cerebellar dysplasia with cysts (Poretti-Boltshauser syndrome).

Cerebellar dysplasia with cysts and abnormal shape of the fourth ventricle, in the absence of significant supratentorial anomalies and of muscular involvement, defines recessively inherited Poretti-Boltshauser syndrome (PBS). Clinical features comprise non-progressive cerebellar ataxia, intellectual disability of variable degree, language impairment, ocular motor apraxia and frequent occurrence of myopia or retinopathy. Recently, loss-of-function variants in the LAMA1 gene were identified in six probands with PBS. Here we report the detailed clinical, neuroimaging and genetic characterization of 18 PBS patients from 15 unrelated families. Biallelic LAMA1 variants were identified in 14 families (93%). The only non-mutated proband presented atypical clinical and neuroimaging features, challenging the diagnosis of PBS. Sixteen distinct variants were identified, which were all novel. In particular, the frameshift variant c.[2935delA] recurred in six unrelated families on a shared haplotype, suggesting a founder effect. No LAMA1 variants could be detected in 27 probands with different cerebellar dysplasias or non-progressive cerebellar ataxia, confirming the strong correlate between LAMA1 variants and PBS.

3D shape analysis of the brain's third ventricle using a midplane encoded symmetric template model

BackgroundStructural changes of the brain's third ventricle have been acknowledged as an indicative measure of the brain atrophy progression in neurodegenerative and endocrinal diseases. To investigate the ventricular enlargement in relation to the atrophy of the surrounding structures, shape analysis is a promising approach. However, there are hurdles in modeling the third ventricle shape. First, it has topological variations across individuals due to the inter-thalamic adhesion. In addition, as an interhemispheric structure, it needs to be aligned to the midsagittal plane to assess its asymmetric and regional deformation. MethodTo address these issues, we propose a model-based shape assessment. Our template model of the third ventricle consists of a midplane and a symmetric mesh of generic shape. By mapping the template's midplane to the individuals’ brain midsagittal plane, we align the symmetric mesh on the midline of the brain before quantifying the third ventricle shape. To build the vertex-wise correspondence between the individual third ventricle and the template mesh, we employ a minimal-distortion surface deformation framework. In addition, to account for topological variations, we implement geometric constraints guiding the template mesh to have zero width where the inter-thalamic adhesion passes through, preventing vertices crossing between left and right walls of the third ventricle. The individual shapes are compared using a vertex-wise deformity from the symmetric template. ResultsExperiments on imaging and demographic data from a study of aging showed that our model was sensitive in assessing morphological differences between individuals in relation to brain volume (i.e. proxy for general brain atrophy), gender and the fluid intelligence at age 72. It also revealed that the proposed method can detect the regional and asymmetrical deformation unlike the conventional measures: volume (median 1.95ml, IQR 0.96ml) and width of the third ventricle. Similarity measures between binary masks and the shape model showed that the latter reconstructed shape details with high accuracy (Dice coefficient ≥0.9, mean distance 0.5mm and Hausdorff distance 2.7mm). ConclusionsWe have demonstrated that our approach is suitable to morphometrical analyses of the third ventricle, providing high accuracy and inter-subject consistency in the shape quantification. This shape modeling method with geometric constraints based on anatomical landmarks could be extended to other brain structures which require a consistent measurement basis in the morphometry.

Toxicity effects of the environmental hormone 4-tert-octylphenol in zebrafish (<i>Danio rerio</i>)

4-tert-octylphenol (4-t-OP), an environmental exogenous estrogen is produced by microbial degradation of alkylphenol polyethoxylates (APEOs). Although it is well known that 4-t-OP can cause the feminization of male, sterility and deficiency of gonad development of aquatic animals by disrupting the endocrine reproductive signaling, less is known about the effects of 4-t-OP on embryonic development. Moreover, the presence of 4-t-OP were detected in umbilical cord blood samples of newborns suggesting infants during development may expose to the risk of 4-t-OP contaminant, hence to investigate the effect of 4-t-OP on physiological function during embryonic development is necessary. In the present study, zebrafish embryos exposed to 4-t-OP were used to evaluate the toxicity of 4-t-OP. The 50% lethal dose (LD50) for wild type zebrafish embryos exposure to 4-t-OP for 3 days is approximately 1.0 mM, and a high ratio of cardiovascular defects were showed in survival embryos. To observe the cardiovascular defects more efficiently, Tg(fil-1:EGFP) zebrafish embryos was used in 4-t-OP exposure treatment. Following exposure Tg(fil-1:EGFP) zebrafish embryos to 4-t-OP at 1.0 mM for 4 days, a highly proportion of defects revealed in cardiovascular system, including pericardical edema, irregular shape or incomplete looping of ventricle and atrium, the absence of intersegmental vessel in the tail of notochord, unformed parachordal vessel and kinks in the caudal vein. The phenotype of cardiovascular defects was accompanied by reduced heart rate and impaired blood circulation. The mRNA expression levels of transcription factors, which are critical for zebrafish heart chamber formation and blood vessel development, were analyzed by RT-PCR. The results showed that the presence of 4-t-OP significantly induce expression level of ERα and ERβ2 , and caused cardiovascular defects by suppressing transcription factor Nkx2.7 , Hand2 , Tbx2a , Tbx2b , Tbx5a , FGF1a , GATA-4 , -5 and -6 in zebrafish. The present study suggests that 4-t-OP affects the cardiovascular development in zebrafish and elucidated that early life exposure to 4-t-OP potentially may take a risk of impaired cardiovascular function.

'Broken-heart syndrome'… Be aware..

Takotsubo cardiomyopathy (TCM), also known by various other names such as broken-heart syndrome, stress-induced cardiomyopathy and apical ballooning syndrome, is an acute, reversible, transient left ventricular dysfunction that was first described by a Japanese cardiologist in 22 patients in the year 1990. The Japanese word ‘takotsubo’ means an octopus trap, used to describe the shape of the left ventricle in this condition during systole. Since its original publication, there have been several case reports describing its occurrence in patients in the periprocedural and perioperative periods, underscoring the importance of the need for awareness about this rare syndrome among anaesthesiologists. There are several case reports published from India too. In this issue of the Indian Journal of Anaesthesia, a case of this entity is reported after thyroidectomy and also one describing its occurrence in a young patient who developed anaphylaxis to cephalosporin intraoperatively during limb salvage surgery for osteosarcoma of the tibia.[1,2] TCM is more common in elderly postmenopausal women, although presentations have been reported in young men and women also. A systematic review of this syndrome has recently been published by Ono and Falcao.[3] The triggering factor for this cardiomyopathy seems to be the elevated levels of plasma catecholamines due to physical or emotional stress, which leads to coronary spasm, direct myocardial toxicity or microvascular impairment. Iatrogenic administration of catecholamines can also be a trigger of this syndrome.[4] Lyon et al. have described a novel pathophysiological hypothesis to explain the myocardial stunning due to catecholamine excess.[5] It has been proposed that apical ballooning could be due to the abundance of beta receptors in this region that can lead to negative inotropy due to change in the intracellular signal trafficking. The Heart Failure Association of the European Society of Cardiology has recently published a position statement on takotsubo syndrome that includes a diagnostic algorithm comprising seven criteria including anatomic features, electrocardiogram (ECG) changes, cardiac biomarkers and reversibility of the ventricular dysfunction.[6]

The Role of Shape and Heart Rate on the Performance of the Left Ventricle.

The left ventricle function is to pump the oxygenated blood through the circulatory system. Ejection fraction is the main noninvasive parameter for detecting heart disease (healthy >55%), and it is thought to be the main parameter affecting efficiency. However, the effects of other parameters on efficiency have yet to be investigated. We investigate the effect of heart rate and left ventricle shape by carrying out 3D numerical simulations of a left ventricle at different heart rates and perturbed geometries under constant, normal ejection fraction. The simulation using the immersed boundary method provide the 3D flow and pressure fields, which enable direct calculation of a new hemodynamic efficiency (H-efficiency) parameter, which does not depend on any reference pressure. The H-efficiency is defined as the ratio of flux of kinetic energy (useful power) to the total cardiac power into the left ventricle control volume. Our simulations show that H-efficiency is not that sensitive to heart rate but is maximized at around normal heart rate (72 bpm). Nevertheless, it is more sensitive to the shape of the left ventricle, which affects the H-efficiency by as much as 15% under constant ejection fraction.

EP03.07: Prenatal diagnosis of Joubert syndrome and related cerebellar disorders and review of literatures

To explore the clinical value of ultrasound imaging and MRI in the diagnosis of fetal Joubert syndrome. Three cases of fetal Joubert syndrome were analysed retrospectively. Recently related literatures were reviewed. Case 1 with suspected occipital encephalocele was transferred to fetal MRI, which confirmed the diagnosis of occipital encephalocele and Joubert syndrome. Case 2 were suffered from prominent cisterna magna, mirror image dextrocardia and polydactyly. After birth, Joubert syndrome were detected by MRI. Prenatal ultrasound imaging and MRI demonstrated Joubert syndrome in Case 3. By reviewing the literatures, ‘Molar tooth' sign and the abnormal shape of the fourth ventricle were found to be features of Joubert syndrome. ‘Molar tooth' sign and the abnormal features of the fourth ventricle are clues to diagnosis fetal Joubert syndrome. The use of MRI and family history of Joubert syndrome may help to make a correct diagnosis.

Toxicity Effects of the Environmental Hormone 4-Tert-Octylphenol in Zebrafish (Danio Rerio)

4-tert-octylphenol (4-t-OP), an environmental exogenous estrogen is produced by microbial degradation of alkylphenol polyethoxylates (APEOs). Although it is well known that 4-t-OP can cause the feminization of male, sterility and deficiency of gonad development of aquatic animals by disrupting the endocrine reproductive signaling, less is known about the effects of 4-t-OP on embryonic development. Moreover, the presence of 4-t-OP were detected in umbilical cord blood samples of newborns suggesting infants during development may expose to the risk of 4-t-OP contaminant, hence to investigate the effect of 4-t-OP on physiological function during embryonic development is necessary. In the present study, zebrafish embryos exposed to 4-t-OP were used to evaluate the toxicity of 4-t-OP. The 50% lethal dose (LD50) for wild type zebrafish embryos exposure to 4-t-OP for 3 days is approximately 1.0 μM, and a high ratio of cardiovascular defects were showed in survival embryos. To observe the cardiovascular defects more efficiently, Tg (fil-1: EGFP) zebrafish embryos was used in 4-t-OP exposure treatment. Following exposure Tg (fil-1: EGFP) zebrafish embryos to 4-t-OP at 1.0 μM for 4 days, a highly proportion of defects revealed in cardiovascular system, including pericardical edema, irregular shape or incomplete looping of ventricle and atrium, the absence of intersegmental vessel in the tail of notochord, unformed parachordal vessel and kinks in the caudal vein. The phenotype of cardiovascular defects was accompanied by reduced heart rate and impaired blood circulation. The mRNA expression levels of transcription factors, which are critical for zebrafish heart chamber formation and blood vessel development, were analyzed by RT-PCR. The results showed that the presence of 4-t-OP significantly induce expression level of ERα and ERβ2, and caused cardiovascular defects by suppressing transcription factor Nkx2.7, Hand2, Tbx2a, Tbx2b, Tbx5a, FGF1a, GATA-4, -5 and -6 in zebrafish. The present study suggests that 4-t-OP affects the cardiovascular development in zebrafish and elucidated that early life exposure to 4-t-OP potentially may take a risk of impaired cardiovascular function.

Permanent ligation of the left anterior descending coronary artery in mice: a model of post-myocardial infarction remodelling and heart failure.

Heart failure is a syndrome in which the heart fails to pump blood at a rate commensurate with cellular oxygen requirements at rest or during stress. It is characterized by fluid retention, shortness of breath, and fatigue, in particular on exertion. Heart failure is a growing public health problem, the leading cause of hospitalization, and a major cause of mortality. Ischemic heart disease is the main cause of heart failure. Ventricular remodelling refers to changes in structure, size, and shape of the left ventricle. This architectural remodelling of the left ventricle is induced by injury (e.g., myocardial infarction), by pressure overload (e.g., systemic arterial hypertension or aortic stenosis), or by volume overload. Since ventricular remodelling affects wall stress, it has a profound impact on cardiac function and on the development of heart failure. A model of permanent ligation of the left anterior descending coronary artery in mice is used to investigate ventricular remodelling and cardiac function post-myocardial infarction. This model is fundamentally different in terms of objectives and pathophysiological relevance compared to the model of transient ligation of the left anterior descending coronary artery. In this latter model of ischemia/reperfusion injury, the initial extent of the infarct may be modulated by factors that affect myocardial salvage following reperfusion. In contrast, the infarct area at 24 hr after permanent ligation of the left anterior descending coronary artery is fixed. Cardiac function in this model will be affected by 1) the process of infarct expansion, infarct healing, and scar formation; and 2) the concomitant development of left ventricular dilatation, cardiac hypertrophy, and ventricular remodelling. Besides the model of permanent ligation of the left anterior descending coronary artery, the technique of invasive hemodynamic measurements in mice is presented in detail.

Quantification of right ventricular volume in dogs: a comparative study between three-dimensional echocardiography and computed tomography with the reference method magnetic resonance imaging.

BackgroundRight ventricular (RV) volume and function are important diagnostic and prognostic factors in dogs with primary or secondary right-sided heart failure. The complex shape of the right ventricle and its retrosternal position make the quantification of its volume difficult. For that reason, only few studies exist, which deal with the determination of RV volume parameters. In human medicine cardiac magnetic resonance imaging (CMRI) is considered to be the reference technique for RV volumetric measurement (Nat Rev Cardiol 7(10):551-563, 2010), but cardiac computed tomography (CCT) and three-dimensional echocardiography (3DE) are other non-invasive methods feasible for RV volume quantification. The purpose of this study was the comparison of 3DE and CCT with CMRI, the gold standard for RV volumetric quantification.Results3DE showed significant lower and CCT significant higher right ventricular volumes than CMRI. Both techniques showed very good correlations (R > 0.8) with CMRI for the volumetric parameters end-diastolic volume (EDV) and end-systolic volume (ESV). Ejection fraction (EF) and stroke volume (SV) were not different when considering CCT and CMRI, whereas 3DE showed a significant higher EF and lower SV than CMRI. The 3DE values showed excellent intra-observer variability (<3%) and still acceptable inter-observer variability (<13%).ConclusionCCT provides an accurate image quality of the right ventricle with comparable results to the reference method CMRI. CCT overestimates the RV volumes; therefore, it is not an interchangeable method, having the disadvantage as well of needing general anaesthesia. 3DE underestimated the RV-Volumes, which could be explained by the worse image resolution. The excellent correlation between the methods indicates a close relationship between 3DE and CMRI although not directly comparable. 3DE is a promising technique for RV volumetric quantification, but further studies in awake dogs and dogs with heart disease are necessary to evaluate its usefulness in veterinary cardiology.

Tako-tsubo Cardiomyopathy on the First Day After Renal Transplantation — Case Report and Literature Review

BackgroundThe etiology of tako-tsubo cardiomyopathy, defined as a transient left ventricular dysfunction in the absence of significant coronary artery stenosis, still remains unclear. This syndrome mainly occurs in postmenopausal women and is often associated with emotional stress or miscellaneous diagnostic and therapeutic procedures. Estimated prevalence of tako-tsubo cardiomyopathy is found in 1% to 2% of patients presenting with suspected acute coronary syndrome. So far there has been only one case report of tako-tsubo cardiomyopathy in a renal transplant recipient. Case reportWe describe the case of a 68-year-old woman with a history of coronary artery disease and coronary artery bypass grafting in whom unspecific transient chest pain and hypotension were observed on the first day after renal transplantation. After transplantation, the patient was anuric with pulmonary congestion and toxic tacrolimus concentrations were observed. Electrocardiogram showed sinus rhythm with left bundle branch block (LBBB) that has not been described before. Plasma cardiac necrosis markers troponin I and creatine kinase MB were mildly elevated. Echocardiography showed severe left ventricular function impairment with characteristic shape of left ventricle. Subsequent cardiac catheterization revealed the absence of angiographic evidence of acute plaque rupture within both coronary arteries and bypass grafts. During the next few days there was marked clinical improvement with resolution of LBBB and full recovery of all biochemical parameters. On discharge, full functional recovery of the left ventricle in echocardiography was observed. Postulated mechanisms of tako-tsubo cardiomyopathy include catecholamine excess, coronary artery spasm, and microvascular dysfunction. On the other hand calcineurin inhibitors are known factors causing coronary epicardial endothelial dysfunction and negatively affecting vasomotor function. ConclusionsTako-tsubo cardiomyopathy in patients after renal transplantation may be at least in part a manifestation of calcineurin inhibitor cardiotoxicity.

New anatomical simulator for pediatric neuroendoscopic practice.

The practice of neuroendoscopic procedures requires many years of training to obtain the adequate skills to perform these operations safely. In this study, we present a new pediatric neuroendoscopic simulator that facilitates training. This realistic simulator was built with a synthetic thermo-retractile and thermo-sensible rubber called Neoderma® which, when combined with different polymers, produces more than 30 different formulae, which present textures, consistencies, and mechanical resistances similar to many human tissues. Silicon and fiberglass molds, in the shape of the cerebral ventricles, constitute the basic structure of the neuroendoscopic training module. The module offers the possibility for practicing many basic neuroendoscopic techniques such as: navigating the ventricular system to visualize important anatomic landmarks (e.g., septal and thalamostriate veins, foramen of Monro, temporal horns, aqueduct, and fourth ventricle), performing third ventriculostomy and choroid plexus cauterization, and resecting intraventricular "tumors" that bleed. It is important to emphasize that it is possible to perform with this simulator not only the rigid but also the flexible endoscopy, with good correspondence to reality and no risks. Notable future perspectives can be considered regarding this new pediatric simulator, for example, to improve the learning curve for nonexperienced neurosurgeons and to spread the flexible endoscopy technique.

Left ventricular ejection fraction by real-time three-dimensional echocardiography : The Necker cube for the naive realism of two-dimensional methods.

Despite a staggering technical progress in echocardiography, in daily clinical practice assessment of left ventricular (LV) ejection fraction (EF) is still often done in a rather inaccurate two-dimensional (2D) manner. Real-time three-dimensional echocardiography (RT3DE) provides a more representative realistic view of LV volumes, thereby being the Necker cube for the naive realism of 2D methods. The Necker cube (Fig. 1a) is an optical illusion first published by the Swiss crystallographer Louis Albert Necker in 1832 [1]. It provides a counter-attack against naive realism, which states that the way we observe the world is the way the world actually is. The Necker cube contradicts this claim, because we see one or the other of two cubes (Fig. 1b), but really, there is no cube there at all, but only a 2D drawing of 12 lines. We see something which is not really there, thus apparently disproving naive realism. This criticism of naive realism supports representative realism. This view argues that we experience reality indirectly by perceptions that represent the real world. For example, if we see a yellow flower, we do not actually see the flower itself but a representation of it. In this way, differences of perception which occur due to changes in the position of the viewer, light conditions, and so on can be easily explained: it is not the object that is changing, only our perception of it. Fig. 1 a The Necker cube. b Like a 2D echocardiographic image, the Necker cube may give the suggestion of a realistic representation of a 3D structure, but really there is only a 2D picture that can be interpreted in different ways Let us go back to echocardiography. Visual estimation of wall motion (‘eyeballing’) is highly subjective, imprecise and poorly reproducible. Nevertheless, some sense of naive realism seems to provide an unrealistic confidence in the accuracy of our eyes. Calculating LV volumes and EF from 2D images by using algorithms such as the biplane method of disks (modified Simpson’s rule) are considered more accurate and better reproducible. However, because of the geometric assumptions of this 2D method, measurements may be inaccurate if the shape of the left ventricle is abnormal or when the acquisition of the 2D images is suboptimal. In other words, like the yellow flower, 2D echocardiographic images are not necessarily a realistic representation of the true left ventricle, but only a perception that is influenced by subjective interpretation and variability in measurements of only a very small 2D portion of the true 3D volume.

Characterization and quantification of curvature using independent coordinates method in the human left ventricle by magnetic resonance imaging to identify the morphology subtype of hypertrophy cardiomyopathy.

The patterns of ventricular hypertrophy are critical determinants of blood flow and function, but are variable. Therefore, it is clinically relevant to assess the hypertrophic shape patterns to better characterize and identify the morphological subtypes. We proposed and developed an independent coordinates method (ICM) to quantify the regional shape of the left ventricle in terms of curvature. 19 normal subjects and 5 HCM (hypertrophic cardiomyopathy) patients with different morphological subtype (i.e., septal hypertrophy, mid-ventricular hypertrophy, reverse curvature septum hypertrophy and sigmoid septum hypertrophy) were recruited and underwent magnetic resonance scans. The curvature along the endocardial and epicardial surface was computed using ICM method and was compared in HCM patients against normal subjects. The results showed that curvature plots are variable in different morphological subtype. The curvature pattern demonstrated the utilities in delineating different subtype. In conclusion, ICM method to quantify regional curvature of the left ventricle from magnetic resonance imaging are feasible in normal subjects and those with hypertrophy cardiomyopathy, which may serve as a novel approach to depict local shape of the left ventricle and to assess the morphological subtype in clinical practice.

Vaccination and triploidy increase relative heart weight in farmed Atlantic salmon, Salmo salar L.

Heart morphology is particularly plastic in teleosts and differs between farmed and wild Atlantic salmon. However, little is known about how different culture practices and sex affect heart morphology. This study investigated how vaccination, triploidy and sex affected heart size and heart morphology (ventricle shape, angle of the bulbus arteriosus) in farmed Atlantic salmon for 18 months following vaccination (from c. 50-3000 g body weight). In addition, hearts were examined histologically after 7 months in sea water. All fish sampled were sexually immature. Vaccinated fish had significantly heavier hearts relative to body weight and a more triangular ventricle than unvaccinated fish, suggesting a greater cardiac workload. Irrespective of time, triploids had significantly heavier hearts relative to body weight, a more acute angle of the bulbus arteriosus and less fat deposition in the epicardium than diploids. The ventricle was also more triangular in triploids than diploids at seawater transfer. Sex had transient effects on the angle of the bulbus arteriosus, but no effect on relative heart weight or ventricle shape. From a morphological perspective, the results indicate that vaccination and triploidy increase cardiac workload in farmed Atlantic salmon.

The shape and function of the left ventricle in Ebstein's anomaly

BackgroundLeft ventricular (LV) failure is common in Ebstein's anomaly, though remains poorly understood. We investigated whether shape deformity impacts LV function. MethodsThree-dimensional models of the right ventricle (RV) and LV from 29 adult Ebstein's patients and nine normal subjects were generated from cardiac magnetic resonance image tracings. LV end diastolic (ED) shape, systolic function, septal motion and ventricular interaction were analyzed. ResultsLV ED volume index was normal in Ebstein's (75±19 vs. 78±11ml/m2 in normals, p=0.50) but the LV was basally narrowed and modestly dilated apically. LV function was reduced globally (ejection fraction (EF) 41±7 vs. 57±5% in normals, p<0.0001) and regionally (decreased mean segment displacement at end systole (ES) in 12/16 segments, basal Z-scores −2.1 to −1.0). Septal dyskinesis was suggested by outward mean segment displacement in at least one basal septal segment in 25 patients (86%) but refuted by septal thickening in 14 (48%), normal septal curvature at ED and ES, and by visually evident basal LV anterior translation in 27 patients (93%). LV EF correlated better with normalized tricuspid annular plane systolic excursion (r=0.70) than with RV EF (r=0.42) or RVEDVI (r=0.18). ConclusionsAlthough the Ebstein's LV has preserved volume, it exhibits basal narrowing, modest apical dilation and global hypokinesis. The apparent basal septal dyskinesis observed in most patients is likely attributable to anterior cardiac translation rather than true paradoxical motion. LV EF is unaffected by RV volume, correlating well instead with RV longitudinal shortening.

Assessment of the right ventricle in pregnant women with and without structural heart disease

We would like to thank the authors for their valuable comments on ourmanuscript and certainlywelcome the suggestion formore interest in right ventricular function in pregnant women with structural heart disease [1,2]. While evaluation of its functioning seems evident in lesions with right sided involvement, it is probably essential in all types of structural heart disease as it becomes more and more evident that left sided dysfunction often involves or induces right ventricular dysfunction [3]. While the latter is often less apparent, it is indeed not less important. The problem remains that there are no data on normal right ventricular function during uncomplicated pregnancy for comparison. It thenbecomesdifficult todiscernbetweenphysiological changes related to pregnancy and pathological changes due to the structural defect. The neglection of right ventricular assessment can largely be attributed to the difficulties in obtaining straightforward representative measurements with ultrasound. Evenmore than for its left counterpart, most parameters only crudely reflect aspects of right ventricular function. Interpretation is then highly dependent of underlying structural abnormalities and changing loading conditions [4]. Assessment of volume and ejection fraction with 2-D ultrasound is severely hampered by the anterior position and complex shape of the right ventricle [4]. The gold standard remains cardiacmagnetic resonance (CMR). 3-D is promising but still remains challenging in patients with structural heart defects [5,6]. In assessing other parameters of right ventricular systolic function, one has to bear in mind that the interplay between intrinsic myocardial performance and loading conditions is evenmore complex as for the left ventricle. Therefore, development of load independent markers of right ventricular function, especially with changing conditions during pregnancy, is essential [3]. As suggested, several parameters like tricuspidal annular plane systolic excursion (TAPSE), Tissue Doppler velocities as well as strain, strain rate and myocardial acceleration during myocardial contraction (IVA), the latter being less load dependent, are promising [4,7]. Still most of them also have their intrinsic limitations and normal values for pregnancy are lacking for comparison. We performed CMR of the right ventricle in a subgroup of our population and will soon submit our data. Unfortunately we did not asses right ventricular function by ultrasound in a systematic way [2]. We think that more research on normal values of both ventricles with the latest ultrasound techniques is primordial in healthy pregnant women and agree that parameters of right ventricular function should then be included in studies of pregnantwomenwith heart disease. Only then will we be able to truly asses the influence of pregnancy on global heart function in these women.

Morphometric Changes in Lateral Ventricles of Patients with Recent-Onset Type 2 Diabetes Mellitus

It is becoming increasingly evident that type 2 diabetes mellitus can have effects on global and regional brain morphology. Ventricular enlargement reflecting cerebral atrophy has been reported particularly in elderly type 2 diabetes patients. However, little is known about its timing through the disease course and morphological variability. Using the combined volumetric and advanced three-dimensional morphological approach, we identified differences in size and shape of the lateral ventricles between recent-onset type 2 diabetes patients and healthy individuals. High-resolution T1-weighted images were obtained from 23 type 2 diabetes patients whose illness duration was less than 1 year and 23 carefully matched healthy individuals. By volume measurement, we found enlarged lateral and third ventricles in type 2 diabetes patients, relative to healthy individuals (F 1,41 = 7.96, P = 0.007; F 1,41 = 11.16, P = 0.002, respectively). Morphological analysis revealed that the expansion of lateral ventricles in the diabetic brain was prominent in the bilateral frontal horns. The current findings suggest that atrophic changes particularly of the anterior frontal lobe can occur as early as the first year after the clinical diagnosis of type 2 diabetes mellitus.

Ventricular Enlargement and its Clinical Correlates in the Imaging Cohort From the ADCS MCI Donepezil/Vitamin E Study

We analyzed the baseline and 3-year T1-weighted magnetic resonance imaging data of 110 amnestic mild cognitive impairment (MCI) participants with minimal hippocampal atrophy at baseline from the Alzheimer's Disease Cooperative Study group MCI Donepezil/Vitamin E trial. Forty-six subjects converted to Alzheimer disease (AD) (MCIc), whereas 64 remained stable (MCInc). We used the radial distance technique to examine the differences in lateral ventricle shape and size between MCIc and MCInc and the associations between ventricular enlargement and cognitive decline. MCIc group had significantly larger frontal and right body/occipital horns relative to MCInc at baseline and significantly larger bilateral frontal, body/occipital, and left temporal horns at follow-up. Global cognitive decline measured with AD Assessment scale cognitive subscale and Mini-Mental State Examination and decline in activities of daily living (ADL) were associated with posterior lateral ventricle enlargement. Decline in AD Assessment scale cognitive subscale and ADL were associated with left temporal and decline in Mini-Mental State Examination with right temporal horn enlargement. After correction for baseline hippocampal volume, decline in ADL showed a significant association with right frontal horn enlargement. Executive decline was associated with right frontal and left temporal horn enlargement.