Morphological Assessment and Possible Clinical Implications of the Left Ventricle Papillary Muscles. Study in a Colombian Population Sample

SUMMARY: Papillary muscles in the left ventricle present multiple anatomic expressions that are relevant for medical fields focusing on the understanding of clinical events involving these structures. Here, the aim was to perform a morphological characterization of the left ventricle papillary muscles in a sample of Colombian population. In the study were included eighty-two hearts from male individuals who underwent autopsy at the Institute of Legal Medicine and Forensic Sciences in Bucaramanga, Colombia. In each heart was carefully performed a longitudinal incision on the obtuse margin to visualize the papillary muscles. Data set was registered, and analysis of the continuous and categorical variables was carried out. Single anterior papillary muscle was observed in 74 samples (90.2 %) whereas this represented only 48 specimens (58.5 %) for the posterior papillary muscle (p = 0.3). Mean length and breadth of the anterior muscle were 29.9 ± 4.94 and 11.74 ± 2.75 mm, and those for the posterior muscle were 27.42 ± 7.08 and 10.83 ± 4.08 mm. Truncated apical shape was the most frequent type observed on the papillary muscles, anterior 41 (50 %) and posterior 37 (45.1 %), followed by flat-topped in the anterior 25 (30.5 %) and bifurcated in posterior muscle 14 (17.1 %). A mean of 9.04 ± 2.75 chordae raised from the anterior and 7.50 ± 3.3 from posterior papillary muscle. In our study we observed a higher incidence of single papillary muscles and slightly larger dimensions than information reported in the literature. The anatomic diversity of the papillary muscles should be considered for the correct image interpretation, valve implantation and performance evaluation on myocardial ischemic events.

Los músculos papilares del ventrículo izquierdo presentan múltiples expresiones anatómicas que son relevantes para las áreas médicas que se centran en la comprensión de los eventos clínicos que involucran estas estructuras. El objetivo fue realizar una caracterización morfológica de los músculos papilares del ventrículo izquierdo en una muestra de población colombiana. En el estudio se incluyeron ochenta y dos corazones de individuos masculinos a los que se les realizó autopsia en el Instituto de Medicina Legal y Ciencias Forenses de Bucaramanga, Colombia. En cada corazón se realizó cuidadosamente una incisión longitudinal en el margen obtuso para visualizar los músculos papilares. Se registró el conjunto de datos y se realizó el análisis de las variables continuas y categóricas. Se observó un solo músculo papilar anterior en 74 muestras (90,2 %), mientras que este rasgo se presentó en 48 muestras (58,5 %) para el músculo papilar posterior (p = 0,3). La longitud y anchura media del músculo anterior fueron 29,9 ± 4,94 y 11,74 ± 2,75 mm, y las del músculo posterior fueron 27,42 ± 7,08 y 10,83 ± 4,08 mm. La forma apical truncada fue el tipo más frecuente observado en los músculos papilares, anterior 41 (50 %) y posterior 37 (45,1 %), seguido de la forma plana en los 25 anteriores (30,5 %) y bifurcada en el músculo posterior 14 (17,1 %). Una media de 9,04 ± 2,75 cuerdas elevadas desde el músculo papilar anterior y 7,50 ± 3,3 desde posterior. En nuestro estudio observamos una mayor incidencia de músculos papilares únicos y dimensiones ligeramente mayores que la información reportada en la literatura. La diversidad anatómica de los músculos papilares debe ser considerada para la correcta interpretación de imágenes, implantación valvular y evaluación del desempeño en eventos isquémicos miocárdicos.

Cardiac Corpuscles: A "New" Morphofunctional Entity? / Corpúsculos Cardíacos: ¿Una "Nueva" Entidad Morfofuncional?

SUMMARY: The existence of "transitional muscular structures" between subendocardial branches (Purkinje fibers) and ventricular working muscle fibers (WF) was first described by the German anatomist, Kurt Goerttler, in 1964. He designated them as "subendocardial nucleus organs." He supposed such fibers functioned as mechanoreceptors, controlling of the intensity of contraction of the ventricular musculature. Brazilian anatomist Ferraz de Carvalho described similar structures in 1993. A thorough literature search failed to identify any other research articles confirming or denying their existence. The objective of this work was to find such structures in subendocardial ventricular walls in human hearts. We collected fifteen formalin-preserved hearts from the Anatomy Department of São Paulo University and sectioned the apical portions on the right and left ventricles according to method used by Goerttler. We utilized conventional histology (light microscopy- LM), scanning electron microscopy (SEM), and a new preservation method called micro- plastination (MP). At the anterior wall of the right ventricle in the subendocardial region between the interventricular septum and moderator band, we found several bundles of fusiform and helicoidal fibers of similar histology to the WF. The bundles measured between 400 and 1150 µm in length and were separated from adjacent muscular fibers by thin collagen fiber, thus acting as a "pseudo capsule." Some structures seemed to be linked to PF and were appeared to be lymphatic and blood vessels and nerves. We called those structures "cardiac corpuscles" (CC). The observation of the previously "unknown" CC in this initial study confirmed the previous descriptions and its discovery may contribute to new perspectives in the study of cardiac muscle structure and function.

La existencia de "estructuras musculares de transición" entre los ramos subendocárdicos (fibras de Purkinje) y las fibras musculares ventriculares activas(FMV) fue descrita por primera vez por el anatomista alemán Kurt Goerttler en 1964, quien las denominó "órganos del núcleo subendocárdico". Supuso que tales fibras funcionaban como mecanoreceptores, controlando la intensidad de la contracción de la musculatura ventricular. El anatomista brasileño Ferraz de Carvalho describió estructuras similares en 1993. Una búsqueda bibliográfica exhaustiva no logró identificar ningún otro artículo de investigación que confirmara o negara su existencia. El objetivo de este trabajo fue encontrar dichas estructuras en las paredes ventriculares subendocárdicas de corazones humanos. Recolectamos 15 corazones conservados en formalina del Departamento de Anatomía de la Universidad de São Paulo y seccionamos las porciones apicales de los ventrículos derecho e izquierdo según el método utilizado por Goerttler. Utilizamos histología convencional (microscopía de luz-LM), microscopía electrónica de barrido (SEM) y un nuevo método de conservación llamado microplastinación (MP). En la pared anterior del ventrículo derecho en la región subendocárdica entre el tabique interventricular y la banda moderadora, encontramos varios haces de fibras fusiformes y helicoidales de histología similar a la FMV. Los haces medían entre 400 y 1150 µm de longitud y estaban separados de las fibras musculares adyacentes por una fina fibra de colágeno, actuando así como una "pseudocápsula". Algunas estructuras parecían estar vinculadas a la fibras de purkinje y parecían ser vasos linfáticos, sanguíneos y nerviosos. Llamamos a esas estructuras "corpúsculos cardíacos" (CC). La observación del CC previamente "desconocido" en este estudio inicial confirmó las descripciones anteriores y su descubrimiento puede contribuir a nuevas perspectivas en el estudio de la estructura y función del músculo cardíaco.

Como eu faço o strain longitudinal do ventrículo direito com softwares automatizados 2D e 3D / My approach to right ventricular longitudinal strain with automated 2D and 3D software

A análise da deformação miocárdica ventricular direita tem surgido como uma ferramenta diagnóstica importante na detecção de disfunção sistólica ventricular direita inicial não detectada pelas técnicas ecocardiográficas convencionais. Além disso, é capaz de trazer informações diagnósticas e prognósticas adicionais aos parâmetros tradicionais de avaliação da função sistólica ventricular direita em diversas patologias. O método ecocardiográfico de escolha para sua avaliação é o strain longitudinal derivado do speckletracking. Ele tem se mostrado mais sensível para pequenas mudanças na função sistólica quando comparado à excursão sistólica do plano do anel tricúspide, estudo da onda s´ ao Doppler tecidual do anel tricúspide e variação da área fracional do ventrículo direito. O avanço da inteligência artificial e a presença de softwares com análise automatizada entram neste cenário visando tornar a aplicabilidade do método mais simples, rápida e com menor variabilidade inter e intraobservador. O objetivo deste artigo de revisão é demonstrar o passo a passo da técnica, desde a otimização e aquisição de imagens até a interpretação dos resultados, com figuras ilustrativas de casos selecionados.(AU)

Right ventricular strain analysis has emerged as an important diagnostic tool in the detection of early right ventricular systolic dysfunction not detected by conventional echocardiography techniques. Furthermore, it is capable of providing additional diagnostic and prognostic information to the traditional parameters for evaluating right ventricular systolic function in various pathologies. The echocardiography method of choice for its assessment is longitudinal strain derived from speckletracking. This method has been shown to be more sensitive for small changes in systolic function when compared to tricuspid annular plane systolic excursion, tissue Doppler imaging of the tricuspid annular s' wave, and right ventricular fractional area change. Advances in artificial intelligence and software with automated analysis have been introduced to this scenario with the aim of making the method simpler and quicker to apply, with lower inter- and intra-observer variability. The objective of this review article is to demonstrate the technique step by step, from image optimization and acquisition to interpretation of results, with illustrative figures of selected cases.(AU)

Multiscale model of heart growth during pregnancy: integrating mechanical and hormonal signaling.

Pregnancy stands at the interface of mechanics and biology. The growing fetus continuously loads the maternal organs as circulating hormone levels surge, leading to significant changes in mechanical and hormonal cues during pregnancy. In response, maternal soft tissues undergo remarkable growth and remodeling to support the mother and baby for a healthy pregnancy. We focus on the maternal left ventricle, which increases its cardiac output and mass during pregnancy. This study develops a multiscale cardiac growth model for pregnancy to understand how mechanical and hormonal cues interact to drive this growth process. We coupled a cell signaling network model that predicts cell-level hypertrophy in response to hormones and stretch to a compartmental model of the rat heart and circulation that predicts organ-level growth in response to hemodynamic changes. We calibrated this multiscale model to data from experimental volume overload and hormonal infusions of angiotensin 2 (AngII), estrogen (E2), and progesterone (P4). We then validated the model's ability to capture interactions between inputs by comparing model predictions against published observations for the combinations of VO + E2 and AngII + E2. Finally, we simulated pregnancy-induced changes in hormones and hemodynamics to predict heart growth during pregnancy. Our model produced growth consistent with experimental data. Overall, our analysis suggests that the rise in P4 during the first half of gestation is an important contributor to heart growth during pregnancy. We conclude with suggestions for future experimental studies that will provide a better understanding of how hormonal and mechanical cues interact to drive pregnancy-induced heart growth.

Extreme altitude induces divergent mass reduction of right and left ventricle in mountain climbers.

Mountain climbing at high altitude implies exposure to low levels of oxygen, low temperature, wind, physical and psychological stress, and nutritional insufficiencies. We examined whether right ventricular (RV) and left ventricular (LV) myocardial masses were reversibly altered by exposure to extreme altitude. Magnetic resonance imaging and echocardiography of the heart, dual x-ray absorptiometry scan of body composition, and blood samples were obtained from ten mountain climbers before departure to Mount Everest or Dhaulagiri (baseline), 13.5 ± 1.5 days after peaking the mountain (post-hypoxia), and six weeks and six months after expeditions exceeding 8000 meters above sea level. RV mass was unaltered after extreme altitude, in contrast to a reduction in LV mass by 11.8 ± 3.4 g post-hypoxia (p = 0.001). The reduction in LV mass correlated with a reduction in skeletal muscle mass. After six weeks, LV myocardial mass was restored to baseline values. Extreme altitude induced a reduction in LV end-diastolic volume (20.8 ± 7.7 ml, p = 0.011) and reduced E', indicating diastolic dysfunction, which were restored after six weeks follow-up. Elevated circulating interleukin-18 after extreme altitude compared to follow-up levels, might have contributed to reduced muscle mass and diastolic dysfunction. In conclusion, the mass of the RV, possibly exposed to elevated afterload, was not changed after extreme altitude, whereas LV mass was reduced. The reduction in LV mass correlated with reduced skeletal muscle mass, indicating a common denominator, and elevated circulating interleukin-18 might be a mechanism for reduced muscle mass after extreme altitude.

Revisiting left atrial volumetry by magnetic resonance imaging: the role of atrial shape and 3D angle between left ventricular and left atrial axis.

BACKGROUND: Accurate measurement of left atrial (LA) volumes is needed in cardiac diagnostics and the follow up of heart and valvular diseases. Geometrical assumptions with 2D methods for LA volume estimation contribute to volume misestimation. In this study, we test agreement of 3D and 2D methods of LA volume detection and explore contribution of 3D LA axis orientation and LA shape in introducing error in 2D methods by cardiovascular magnetic resonance imaging. METHODS: 30 patients with prior first-ever ischemic stroke and no known heart disease, and 30 healthy controls were enrolled (age 18-49) in a substudy of a prospective case-control study. All study subjects underwent cardiac magnetic resonance imaging and were pooled for this methodological study. LA volumes were calculated by biplane area-length method from both conventional long axis (LAVAL-LV) and LA long axis-oriented images (LAVAL-LA) and were compared to 3D segmented LA volume (LAVSAX) to assess accuracy of volume detection. 3D orientation of LA long axis to left ventricular (LV) long axis and to four-chamber plane were determined, and LA 3D sphericity indices were calculated to assess sources of error in LA volume calculation. Shapiro-Wilk test, Bland-Altman analysis, intraclass and Pearson correlation, and Spearman's rho were used for statistical analysis. RESULTS: Biases were - 9.9 mL (- 12.5 to - 7.2) for LAVAL-LV and 13.4 (10.0-16.9) for LAVAL-LA [mean difference to LAVSAX (95% confidence interval)]. End-diastolic LA long axis 3D deviation angle to LV long axis was 28.3 ± 6.2° [mean ± SD] and LA long axis 3D rotation angle to four-chamber plane 20.5 ± 18.0°. 3D orientation of LA axis or 3D sphericity were not correlated to error in LA volume calculation. CONCLUSIONS: Calculated LA volume accuracy did not improve by using LA long axis-oriented images for volume calculation in comparison to conventional method. We present novel data on LA axis orientation and a novel metric of LA sphericity and conclude that these measures cannot be utilized to assess error in LA volume calculation. TRIAL REGISTRATION: Main study Searching for Explanations for Cryptogenic Stroke in the Young: Revealing the Etiology, Triggers, and Outcome (SECRETO; NCT01934725) has been registered previously.

Right ventricular anatomical and functional parameters in healthy Mexican term newborns / Parámetros anatómicos y funcionales del ventrículo derecho en recién nacidos Mexicanos sanos

Abstract Objective: Right ventricle (RV) function plays an important role during fetal and neonatal transitional circulation. Despite the published echocardiography guidelines in children including neonates, there is scare evidence on RV assessment using echocardiography in Mexican neonates. This study was aimed at assessing RV function and anatomical measures in healthy term newborns and defines normal values in this cohort of patients. Methods: A prospective study involving healthy term newborns in a single center were enrolled in the study to assess RV, all patients were recruited within 24-72 h after birth. The right ventricular assessment was performed as per American Society of Echocardiography's guidelines. Results: Seventy healthy term newborns with a median gestational age of 38 (38.5 ± 2.7) weeks had RV function assessment and anatomical structures measures with a predefined ten echocardiographic parameters protocol. The mean values for: tricuspid valve diameter was 13 mm ± 1.8, basal diameter of the RV 16.7 mm ± 2, RV length 27.8 mm ± 2.2, mid cavity diameter 14.3 mm ± 1.7, RV-anteroinferior basal diameter 21.5 mm ± 2.5, tricuspid regurgitation gradient 13.3 mmHg ± 5.9, tricuspid annular plane systolic excursion 8.7 mm, right ventricular fractional area change (RVFAC) 4 chamber (%) 40.6 ± 7.5, tricuspid E/A 0.7 ± 0.5, myocardial velocities (cm/s) E´ 8 ± 2.7, A´ 9.6 ± 2.4, S´ 6.9 ± 1.2, myocardial performance index 0.5 ± 0.1, RVFAC 3 chamber (%) 37.8 ± 15.8, and pulmonary acceleration time mean value 58.8 ± 14.9. Flattening of interventricular septum was seen in 13% infants. Conclusions: This study describes echocardiographic parameters for anatomical structures and assessment of RV function in healthy term newborns during transitional circulation. We reported novel anatomical measures of the RV; this information can provide normal reference range values and be referenced while assessing RV function in normal and sick newborns during transitional circulation.

Resumen Objetivo: Realizar una valoración ecocardiográfica de parámetros anatómicos y funcionales del ventrículo derecho (VD) en recién nacidos de término (RNT) sanos durante el periodo transicional. Método: Estudio prospectivo en RNT sanos de la Unidad de Cuidados Intensivos Neonatales del Hospital Español. Todos los pacientes fueron estudiados en las primeras 24-72 horas de vida, con base en las guías de la American Society of Echocardiography. Resultados: Se estudiaron 70 RNT sanos con una media de edad gestacional de 38 semanas de gestación (38.5 ± 2.7); en estos pacientes se obtuvieron 10 parámetros ecocardiográficos. El valor medio obtenido para la válvula tricúspide fue de 13 ± 1.8 mm, diámetro basal del VD 16.7 ± 2 mm, longitud 27.8 ± 2.2 mm, cavidad media del VD 14.3 ± 1.7 mm, diámetro basal anteroinferior 21.5 ± 2.5 mm, gradiente de insuficiencia tricuspídea 13.3 ± 5.9 mmHg, tricuspid annular plane systolic excursion (TAPSE) 8.7 mm, Fracción de acortamiento del VD (FAVD) 4 cámaras (%) 40.6 ± 7.5, E/A tricuspídeo 0.7 ± 0.5, velocidades miocárdicas (cm/s) E´ 8 ± 2.7, A´ 9.6 ± 2.4, S´ 6.9 ± 1.2, índice de rendimiento miocárdico 0.5 ± 0.1, FAVD 3 cámaras (%) 37.8 ± 15.8, tiempo de aceleración pulmonar 58.8 ± 14.9. Conclusiones: Este estudio describe parámetros anatómicos y funcionales del VD en RNT sanos durante el periodo de transición. Se reportan valores de normalidad que pueden servir como referencia.

A randomised controlled trial to examine the effects of cinacalcet on bone and cardiovascular parameters in haemodialysis patients with advanced secondary hyperparathyroidism.

BACKGROUND: Secondary hyperparathyroidism may lead to increased cardiovascular risk. The use of cinacalcet may improve bone and cardiovascular health with improved parathormone (PTH) and phosphate control. METHODS: This is an open-label prospective randomised controlled trial to compare progression of cardiovascular and chronic kidney disease mineral and bone disorder (CKD-MBD) parameters. Patients were randomised to receive cinacalcet alongside standard therapy or standard therapy alone. Thirty-six haemodialysis patients who had > 90 days on dialysis, iPTH > 300 pg/mL, calcium > 2.1 mmol/L and age 18-75 years were included. Following randomization, all 36 patients underwent an intensive 12-week period of bone disease management aiming for iPTH 150-300 pg/mL. The primary outcome was change in vascular calcification using CT agatston score. Secondary outcomes included pulse wave velocity (PWV), left ventricular mass index (LVMI), carotid intima-media thickness (CIMT), augmentation index (Aix) and bone measurements. The above measurements were obtained at baseline and 12 months. RESULTS: There was no evidence of a group difference in the progression of calcification (median change (IQR) cinacalcet: 488 (0 to1539); standard therapy: 563 (50 to 1214)). In a post hoc analysis combining groups there was a mean (SD) phosphate reduction of 0.3 mmol/L (0.7) and median (IQR) iPTH reduction of 380 pg/mL (- 754, 120). Regression of LVMI and CIMT was seen (P = 0.03 and P = 0.001) and was significantly associated with change of phosphate on multi-factorial analyses. CONCLUSIONS: With a policy of intense CKD-MBD parameter control, no significant benefit in bone and cardiovascular markers was seen with the addition of cinacalcet to standard therapy over one year. Tight control of hyperphosphataemia and secondary hyperparathyroidism may lead to a reduction in LVMI and CIMT but this needs further investigation. Although the sample size was small, meticulous trial supervision resulted in very few protocol deviations with therapy.

Efectos de la actividad locomotriz voluntaria gestacional sobre la morfología cardiaca en crías murinas / Effects of gestational voluntary locomotor activity on cardiac morphology in murine offspring

RESUMEN: El objetivo del presente estudio es analizar los efectos de la actividad locomotriz voluntaria gestacional, como un tipo de entrenamiento físico, sobre la morfología de la bomba cardíaca de la cría, en modelo murino de la cepa CF-1. 12 hembras gestantes fueron divididas aleatoriamente en un grupo control y un grupo que realizó actividad locomotriz voluntaria, accediendo a una rueda de actividad durante los primero 12 días de gestación. Se evaluó la morfología cardiaca mediante cortes transversales, midiendo espesor y área de las paredes del ventrículo derecho, ventrículo izquierdo y septum, tanto en valores absolutos como en valores relativos a la masa corporal del individuo. Se observó que la masa corporal de las crías control (GC) fue significativamente mayor que las del grupo cuyas hembras accedieron a la rueda de actividad (GE) (p<0.01). Solo hubo diferencias en los valores absolutos de espesores y áreas miocárdicas de ventrículo derecho, entre el grupo GE y GC (p<0.05), pero al evaluar los espesores y áreas relativos a la masa corporal se observó que las crías del grupo GE presentaron espesores y áreas significativamente mayores que las que grupo GC (p<0.01). En conclusión, la actividad física gestacional altera el desarrollo morfológico de la bomba cardíaca en ratones CF-1, aumentando significativamente el espesor y área de las paredes miocárdicas en relación a la masa corporal total de la cría.

SUMMARY: The objective of the present study is to analyze the effects of gestational voluntary locomotor activity, as a type of physical training, on the morphology of the offspring´s heart pump, in a murine model of the CF-1 strain. Twelve (12) pregnant females were randomly divided in a control group and a group performing voluntary locomotor activity, by accessing an activity wheel during the first 12 days of gestation. Cardiac morphology was evaluated using cross sections, measuring thickness and area of the walls of the right ventricle, left ventricle, and septum, both in absolute values and values relative to the individual's body mass. It was observed that the body mass of the control pups (CG) was significantly higher than those of the group whose females accessed the activity wheel (GE) (p <0.01). Differences were observed only in absolute values of thickness and myocardial areas of the right ventricle, between the GE and GC group (p <0.05). However, when evaluating the thickness and areas relative to body mass, it was observed that the offspring of the GE group presented thicknesses and areas significantly larger than those in the GC group (p <0.01). In conclusion, gestational physical activity alters the morphological development of the heart pump in CF-1 mice, significantly increasing the thickness and area of the myocardial walls in relation to offspring total body mass.

Morphological variations of the conduction system in the atrioventricular zone and its clinical relationship in different species.

Atrioventricular node is responsible for delaying the passage of the electrical impulse to ventricles in order to protect them from fast depolarizations coming from the atria. The importance of this study is to identify the morphological variations of the components of atrioventricular zone that affect the conduction system and its clinical relationship in different species of mammals. We analyzed ten human hearts, nine from horses, eight from pigs, and five from dogs without a clinical history of cardiac pathologies. Histological section thickness of 5 µm were obtained with a microtome and stained with hematoxylin-eosin and Masson's trichrome. We observed both an increase in collagen fibers and a decrease in the size of P cells (nodal pacemaker cells) within the atrioventricular node in dogs, horses and pigs in cases that presented cartilage in fibrous body. The percentage of fundamental substance in atrioventricular node was significantly higher in dogs and the percentage of collagen fibers was higher in pigs, both than in humans. The presence of cartilaginous metaplasia in cardiac fibrous skeleton from different species decreases the size of atrioventricular node and its cells and increases the percentage of collagen fibers within the node, which can reduce the transmission of the electrical impulse to ventricles and therefore predispose to the presentation of ventricular arrhythmias. Morphometric analysis has allowed us to objectively quantify each of the components of AV node and compare them in the different species.

Anatomia macroscópica interna e avaliação elétrica do coração de Bradypus variegatus / Internal macroscopic anatomy and electrical evaluation of the Bradypus variegatus heart

The Bradypus variegatus species presents peculiar anatomophysiological properties and many aspects of its organic systems still need to be clarified, especially regarding the cardiovascular system, given its participation in vital activities. Disorderly anthropic action has had drastic consequences in sloth populations and the need to treat sick and injured animals is increasingly common. To this end, the importance of knowing its characteristics is emphasized. Therefore, this study proposed to describe the internal macroscopic structures of the sloth's heart, as well as to measure the ventricular walls and indicate the electrical activity of the organ. For the dissections, 15 Bradypus variegatus cadavers were used (1 young female, 9 adults females and 5 adult males) belonging to the Área de Anatomia of the Departamento de Morfologia e Fisiologia Animal (DMFA), Universidade Federal Rural de Pernambuco (UFRPE), Recide, PE, Brazil. After they were fixed and preserved, the specimens received a midsagittal incision in the chest, followed by soft tissue folding and removal of ribs to access the heart. The organ was derived from the cavity and sectioned sagittal medially to identify its internal anatomy. Ventricular walls and interventricular septum were measured with a steel caliper (150 mm / 0.02 mm). An electrocardiogram was performed to determine the electrical profile on 5 healthy B. variegatus sloths, living under semi-livestock conditions at the Recife Zoo, PE, Brazil. The electrodes were taken from the regions, scapular and glutes of the animals that were called hugging a keeper during the procedure, carried out in the Zoo itself, using a portable device. Based on the data obtained, sloths have cardiac chambers separated by septa, however between atria and ventricles, in both antimeres, there are atrioventricular ostia, where valves are found, consisting of 3 valves on the right and 2 on the left. The atria are practically smooth inside and have their cavity enlarged by the atria, the right being larger than the left, these having a greater amount of pectineal muscles in relation to the atria. The ventricles have trabeculae and papillary muscles, 3 on the right and 2 on the left. These muscles hold the tendinous chords that connect the valves. The existence of trabeculae marginal septum was not evidenced. The thickness of the wall of the left ventricle, as well as that of the interventricular septum, proved to be greater than the thickness of the wall of the right ventricle, regardless of the age or sex of the animals. Based on the electrocardiographic recordings, the sloths presented sinus rhythm, with a heart rate between 67 and 100 bpm. The electrical axis ranged from -60º to -90º. The P wave is smoother than the QRS complex. While the S-T segment was classified as isoelectric. The T wave was shown to be + and predominantly > or = at 25% of the S wave, which characterized an rS type QRS deflection in both females and males. The general characteristics of the cardiac chambers in sloths are similar to those observe in other domestic and wild mammals. However, the presence of pectineal muscles associated with the atria and auricles differs from that observed in mammals such as the paca and raccoon and in birds such as the ostrich, which have trabecular structures in these cavities. The number of valves in sloths is equal to the anteater. However, it has a marginal trabeculae septum, not seen in Bradypus variegatus. According to the electrocardiographic findings, the rhythm was sinus, but much lower than that observed in the capuchin monkey, which also maintains arboreal habits.(AU)

Evaluation of a delineation software for cardiac atlas-based autosegmentation: An example of the use of artificial intelligence in modern radiotherapy.

PURPOSE: The primary objective of this work was to implement and evaluate a cardiac atlas-based autosegmentation technique based on the "Workflow Box" software (Mirada Medical, Oxford UK), in order to delineate cardiac substructures according to European Society of Therapeutic Radiation Oncology (ESTRO) guidelines; review and comparison with other cardiac atlas-based autosegmentation algorithms published to date. MATERIALS AND METHODS: Of an atlas of data set from 20 breast cancer patients' CT scans with recontoured cardiac substructures creation according to the ESTRO guidelines. Performance evaluation on a validation data set consisting of 20 others CT scans acquired in the same treatment position: cardiac substructure were automatically contoured by the Mirada system, using the implemented cardiac atlas, and simultaneously manually contoured by a radiation oncologist. The Dice similarity coefficient was used to evaluate the concordance level between the manual and the automatic segmentations. RESULTS: Dice similarity coefficient value was 0.95 for the whole heart and 0.80 for the four cardiac chambers. Average Dice similarity coefficient value for the left ventricle walls was 0.50, ranging between 0.34 for the apical wall and 0.70 for the lateral wall. Compared to manual contours, autosegmented substructure volumes were significantly smaller, with the exception of the left ventricle. Coronary artery segmentation was unsuccessful. Performances were overall similar to other published cardiac atlas-based autosegmentation algorithms. CONCLUSION: The evaluated cardiac atlas-based autosegmentation technique, using the Mirada software, demonstrated acceptable performance for cardiac cavities delineation. However, algorithm improvement is still needed in order to develop efficient and trusted cardiac autosegmentation working tools for daily practice.

Cells of the adult human heart.

Cardiovascular disease is the leading cause of death worldwide. Advanced insights into disease mechanisms and therapeutic strategies require a deeper understanding of the molecular processes involved in the healthy heart. Knowledge of the full repertoire of cardiac cells and their gene expression profiles is a fundamental first step in this endeavour. Here, using state-of-the-art analyses of large-scale single-cell and single-nucleus transcriptomes, we characterize six anatomical adult heart regions. Our results highlight the cellular heterogeneity of cardiomyocytes, pericytes and fibroblasts, and reveal distinct atrial and ventricular subsets of cells with diverse developmental origins and specialized properties. We define the complexity of the cardiac vasculature and its changes along the arterio-venous axis. In the immune compartment, we identify cardiac-resident macrophages with inflammatory and protective transcriptional signatures. Furthermore, analyses of cell-to-cell interactions highlight different networks of macrophages, fibroblasts and cardiomyocytes between atria and ventricles that are distinct from those of skeletal muscle. Our human cardiac cell atlas improves our understanding of the human heart and provides a valuable reference for future studies.

Effect of endoprostheses on pulse wave velocity and its long-term outcomes after thoracic endovascular aortic repair.

BACKGROUND: The purpose of this study was to evaluate the changes in pulse wave velocity and left ventricular dimensions in patients undergoing stent-graft treatment for aortic arch aneurysm. METHODS: From July 2008 to February 2019, 86 patients underwent thoracic endovascular aortic repair of an aortic arch aneurysm. Changes in pulse wave velocity (PWV), echocardiogram findings, and long-term outcomes were compared between endoskeleton type (n = 60) and exoskeleton type stent-graft (n = 26). RESULTS: There was no significant difference in patient demographics except for diabetes which was more observed in endoskeleton type (p = 0.017). There was a significant increase in PWV in exoskeleton type after surgery, which further progressed at a median follow-up of 32 months (before: 2047 cm/s vs. after: 2259 cm/s vs. follow-up: 2486 cm/s, p = 0.010, p = 0.017). No significant difference was observed in endoskeleton type (before: 1980 cm/s vs. after: 2058 cm/s, vs. follow-up: 2042 cm/s, p = 0.25, p = 0.34). Echocardiogram performed at a median period of 46.3 months, revealed a significant increase in left ventricular diastolic volume (LVDV) (before: 107.4 ± 20.6 ml vs. follow-up: 127.7 ± 27.5 ml, p = 0.003) and decrease in e' (before: 5.5 ± 1.78 cm/s vs. follow-up: 4.7 ± 1.72 cm/s, p = 0.012) in exoskeleton type, while no significant change was observed in endoskeleton type (LVDV: before: 102.6 ± 32.3 ml vs. follow-up: 96.9 ± 35.4 ml, p = 0.74; e': before: 4.4 ± 1.21 cm/s vs. follow-up: 4.8 ± 1.40 cm/s, p = 0.68). At the median period of 61.3 months, there was no significant difference in long-term mortality (p = 0.89). However, the endoskeleton type was associated with a lower incidence of a cardiac event (p = 0.034) and cerebrovascular event (p = 0.029). CONCLUSION: Types of endoprosthesis might affect differently on physiological changes and its accommodated risk factors after surgery.

Quantification of Initial Right Ventricular Dimensions by Computed Tomography in Infants with Congenital Heart Disease and a Hypoplastic Right Ventricle.

OBJECTIVE: To demonstrate the feasibility of using cardiothoracic CT for quantification of the initial right ventricle (RV) dimensions in infants with congenital heart disease (CHD) and a hypoplastic RV and to compare these measurements with those obtained in a control group with CHD without a hypoplastic RV. MATERIALS AND METHODS: Initial RV dimensions, including RV volumes, RV/left ventricle (LV) volume ratios, atrioventricular valve annulus diameter ratios, and RV/LV length ratios based on CT data, were collected from 57 infants with CHD and a hypoplastic RV (hypoplastic RV group; age range, 1 day to 6 months) and 33 infants with tetralogy of Fallot (control group; age range, 1 day to 6 months) and compared between the 2 groups. The type of final surgery was also evaluated in the hypoplastic RV group over a follow-up period of 3-8 years. RESULTS: The RV and LV volumes and lengths were successfully quantified in all 90 patients. The tricuspid valve annulus diameter could not be measured in cases showing muscular tricuspid atresia and double-inlet LV. The initial RV dimensions quantified by CT were significantly lower for the hypoplastic RV group than for the control group (p < 0.001). The types of final surgery performed in the hypoplastic RV group were univentricular repair in 46 patients, biventricular repair in 4 patients, or an indeterminate surgery in 7 patients. CONCLUSION: Initial RV dimensions in infants with CHD and a hypoplastic RV can be quantified by CT and are substantially smaller than those in infants with tetralogy of Fallot.

Results of Left Ventricular Reconstruction With and Without Mitral Valve Surgery.

BACKGROUND: This study aims to compare the midterm outcomes of left ventricular reconstruction with those of left ventricular reconstruction plus mitral valve surgery in patients with left ventricular aneurysm due to anterior myocardial infarction and moderate mitral regurgitation. METHODS: A total of 523 patients (75 who underwent left ventricular reconstruction plus mitral valve surgery and 448 who underwent left ventricular reconstruction) with concomitant moderate mitral regurgitation were included in the study population. All-cause mortality was considered the primary endpoint. Major adverse cardiovascular and cerebrovascular events, including death, myocardial infarction, stroke, and subsequent mitral valve surgery, were considered secondary endpoints. Multivariable proportional hazards Cox regression models were used to assess the associations between groups and outcomes. In the sensitivity analysis we excluded patients who did not undergo coronary artery bypass graft and repeated the statistical analysis above. RESULTS: The median follow-up time among all patients was 41 months. There was no significant difference between the left ventricular reconstruction plus mitral valve surgery and the left ventricular reconstruction groups with regard to all-cause mortality (P = .208) and major adverse cardiovascular and cerebrovascular events (P = .817) after adjustment for covariates. In the sensitivity analysis there was no significant difference between the left ventricular reconstruction plus mitral valve surgery and left ventricular reconstruction groups with regard to all-cause mortality (P = .158) and major adverse cardiovascular and cerebrovascular events (P = .651) after adjustment for covariates. CONCLUSIONS: The clinical outcomes of left ventricular reconstruction are comparable with those of left ventricular reconstruction plus mitral valve surgery in patients with left aneurysm and moderate mitral regurgitation.

Análise Ecocardiográfica das Câmaras Direitas segundo Sexo e Superfície Corporal / Echocardiographic Assessment of Right Chambers by Gender and Body Surface Area

Introdução: A avaliação sistemática das dimensões e da função das câmaras direitas, de acordo com sexo, idade, superfície corporal e índice de massa corporal, não é uniformemente realizada. Objetivo: Avaliar, ao ecocardiograma transtorácico, as dimensões e a função das câmaras direitas de acordo com o sexo, superfície corporal e índice de massa corporal em uma população ambulatorial. Métodos: Estudo observacional, transversal. Foram selecionados 81 pacientes, 60,4 ± 13,5 anos, de ambos os sexos (57 mulheres, 70%). Foram avaliados: diâmetro proximal do ventrículo direito, basal do ventrículo direito, médio e longitudinal; área do átrio direito e volume do átrio direito; espessura da parede livre do ventrículo direito; excursão sistólica do anel valvar tricúspide; e Doppler tecidual do anel tricúspide, onda S'. Resultados: O sexo feminino apresentou menores diâmetros em relação ao sexo masculino (teste t de Student) de diâmetro proximal do ventrículo direito (20,6 mm ± 2,4 vs. 22,7 mm ± 2,2; p = 0,001), basal do ventrículo direito (34,4 mm ± 3,5 vs. 38,2 mm ± 4,8; p < 0,001), diâmetro médio do ventrículo direito (27 mm ± 3,3 vs. 32,4 mm ± 4,9; p < 0,001), área do átrio direito (13,7 cm² ± 2,7 vs. 16,6 cm² ± 3,9; p = 0,002) e volume do átrio direito (37 mL ± 10,6 vs. 50,7 mL ± 15,6 ; p = 0,002). O índice de massa corporal e a superfície corporal se correlacionaram positivamente com o diâmetro proximal do ventrículo direito (coeficiente de correlação - CC 0,24; p = 0,03), diâmetro basal do ventrículo direito (CC 0,22; p = 0,04), diâmetro médio do ventrículo direito (CC 0,23; p = 0,04), diâmetro longitudinal do ventrículo direito (CC 0,28; p = 0,01), área do átrio direito (CC 0,40; p = 0,001) e volume do átrio direito (CC 0,24; p = 0,0006). Conclusão: As médias dos diâmetros ventriculares, área e volume atriais direitos foram menores no sexo feminino. Foi encontrada correlação positiva destes parâmetros com o índice de massa corporal e a superfície corporal. Os valores da excursão sistólica do anel valvar tricúspide e S' não foram influenciados por sexo, índice de massa corporal e superfície corporal.

Introduction: Assessment of right chambers dimensions and function according to gender, age, body surface area and body mass index is not uniformly performed. Objective: To evaluate, by transthoracic echocardiography dimensions and function of right chambers, according to gender, body surface area and body mass index in an outpatient population. Method: Cross-sectional study. Eighty-one patients were selected, 60.4 ± 13.5 years (57 women, 70%). Parameters assessed were the following: proximal, basal, medium and longitudinal, right ventricle diameter; right atrium area and right atrium volume; right ventricle wall thickness; tricuspid annular plane systolic excursion; and tricuspid annulus tissue Doppler and S' wave. Results: Female sex presented lower diameters (Student's t-test) of proximal right ventricle diameter (20.6 mm ± 2.4 vs. 22.7 mm ± 2.2; p = 0.001), basal right ventricle diameter (34,4 mm ± 3,5 vs. 38,2 mm ± 4,8; p <0.001), medium right ventricle diameter (27 mm ± 3.3 vs. 32.4 mm ± 4.9; p <0.001), right atrium area (13.7 cm² ± 2.7 vs. 16.6 cm² ± 3.9; p = 0.002) and right atrium volume (37 mL ± 10.6 vs.

Avaliação do ventrículo esquerdo em pacientes com DPOC e hipoxemia noturna / Evaluation of the left ventricle in patients with COPD and nocturnal hypoxemia

RESUMO Objetivo Verificar a associação entre massa e espessura do ventrículo esquerdo (VE) e presença de hipoxemia noturna significativa em pacientes portadores de DPOC com hipoxemia diurna leve. Métodos Estudo transversal realizado em pacientes ambulatoriais, clinicamente estáveis, portadores de DPOC e hipoxemia leve (saturação de oxigênio ≥ 90 a ≤ 94%, identificados por oximetria não invasiva) em um centro clínico especializado no atendimento de doenças respiratórias em Goiânia (GO). Todos foram submetidos a avaliação clínica, espirometria, polissonografia, ecocardiografia, gasometria arterial, teste de caminhada de 6 minutos e radiografia de tórax. Resultados Foram avaliados 64 pacientes com DPOC e hipoxemia noturna. Pacientes com hipoxemia noturna significativa apresentaram parâmetros ecocardiográficos associados a mais quantidade de musculatura do VE quando comparados a pacientes com hipoxemia noturna leve. A relação entre volume/massa do VE foi significativamente menor no grupo com hipoxemia noturna significativa (0,64 ± 0,13 versus 0,72 ± 0,12; p = 0,04) e a espessura diastólica do septo interventricular e a espessura diastólica da parede posterior do VE foram significativamente maiores nesse grupo (9,7 ± 0,92 versus 9,1 ± 0,90; p = 0,03) (9,7 ± 1,0 versus 8,9 ± 1,0; p = 0,01). O tempo de sono REM com saturação abaixo de 85% prediz significativamente a espessura do septo (ajuste para índice de massa corporal [IMC], idade e pressão arterial média; r2 = 0,20; p = 0,046). Conclusão Em indivíduos portadores de DPOC e hipoxemia noturna significativa, foi observada associação entre hipoxemia severa no sono REM e parâmetros ecocardiográficos que indicam aumento da massa do VE. Tal fato sugere que esse subgrupo de indivíduos pode se beneficiar de uma avaliação ecocardiográfica do VE.

ABSTRACT Objective To verify association between left ventricular (LV) mass and thickness and the presence of significant nocturnal hypoxemia in patients with COPD with mild diurnal hypoxemia. Methods A cross-sectional study carried out in clinically stable outpatients with COPD and mild hypoxemia (oxygen saturation ≥90 to ≤94%, identified by noninvasive oximetry) in a clinic specialized in the treatment of respiratory diseases in Goiânia-GO. All patients were submitted to clinical evaluation, spirometry, polysomnography, echocardiography, arterial blood gas analysis, 6-minute walk test and chest X-ray. Results Patients with significant nocturnal hypoxemia had echocardiographic parameters associated with increase of LV musculature when compared to patients with mild nocturnal hypoxemia. The LV volume/mass ratio was significantly lower in the group with significant nocturnal hypoxemia (ratio 0.64 ± 0.13 versus 0.72 ± 0.12, p = 0.04), the thickness diastolic diameter of the interventricular septum and the diastolic thickness of the LV posterior wall were significantly higher in this group (9.7 ± 0.92 versus 9.1 ± 0.90 p = 0.03), (9.7 ± 1.0 versus 8.9 ± 1.0, p = 0.01. The time in REM sleep with saturation below 85% significantly predicted septum thickness (adjustment for BMI, age and mean blood pressure, r2 = 0.20; p = 0.046). Conclusion We observed association between severe REM sleep hypoxemia and echocardiographic parameters indicating increased LV mass in individuals with COPD and significant nocturnal hypoxemia. This suggests that this subgroup of individuals may benefit from an echocardiographic evaluation of the left ventricle.

Análisis del Ventrículo derecho / Analysis of the right ventricle

Resumen El ventrículo derecho, históricamente, ha sido en gran medida olvidado e y la gran mayoría de las técnicas diagnósticas,los abordajes terapéuticos y las investigaciones clínicas están dirigidas al ventrículo izquierdo. Con una anatomía y fisiologíamuy diferente a su contraparte izquierda, el ventrículo derecho dispone de limitadas opciones terapéuticas cuando éste falla, lo cual empeora enormemente el pronóstico del paciente. La presente revisión pretende hacer un análisis de la anatomía, fisiología, fisiopatología, estudios de imagen y tratamiento de la falla ventricular derecha con el fin de retomar su importancia en la cardiología actual.

Abstract The right ventricle has been, historically, largely forgotten and the vast majority of diagnostic techniques, therapeutic approaches and clinical research are directed to the left ventricle. With a very different anatomy and physiology from its left counterpart, the right ventricle has limited therapeutic options when it fails, which greatly worsens the patient's prognosis. The present review intends to analyze the anatomy, physiology, physiopathology, imaging studies and treatment of right ventricular failure in order to resume its importance in current cardiology.