Temporally Segmented Directionality in the Motor Cortex.

Developing models of the dynamic and complex patterns of information processing that take place during behavior is a major thrust of systems neuroscience. An underlying assumption of many models is that the same set of rules applies across different conditions. This has been the case for directional tuning during volitional movement; a single cosine function has been remarkably robust for describing the encoding of movement direction in different types of neurons, in many locations of the nervous system, and even across species. However, detailed examination of the tuning time course in motor cortex suggests that direction coding may be labile. Here, we show that there are discrete time epochs within single reaches, between which individual neurons change their tuning. Our findings suggest that motor cortical activity patterns may reflect consistent changes in the state of the control system during center-out reaching. These transitions are likely linked to different behavioral components, suggesting that the task defines changes in the operational structure of the control system.

Jump percentile: a proposal for evaluation of high level sportsmen.

AIM: The goal of this study was to determine reference values of explosive strength for Spanish professional athletes using a force platform. Reference values are displayed as a sports-independent percentile distribution. METHODS: A total of 323 elite male athletes (age: 20.38 ± 4.65 years, body mass: 75.04 ± 14.30 kg, height: 178.62 ± 14.18 cm) from different disciplines performed the following test: squat jump (SJ), countermovement jump (CMJ), Abalakov test (AB), drop jump (DJ) and repeated jumps (RJ). We calculated: relative peak power, relative peak force, maximal height, symmetry index, explosive index of strength, relative effective impulse, duration of jump, elastic capacity, eccentric time, action of arm, jump number, average height, intensity and fatigue index of force. RESULTS: Significant differences were found among sports disciplines (P<0.05) in relative peak power, maximal height and relative effective impulse during the SJ, CMJ and AB tests. No significant differences were found among disciplines in DJ variables. In RJ, the main variable characterizing the disciplines analyzed was average height, which showed a significant negative association with athletics, soccer, volleyball and gymnastics. CONCLUSION: The results obtained suggest that a percentile table may be useful in assessing explosive strength in athletes, regardless of there being any reference values available for their sports discipline.

Spatial aggregation patterns in four mistletoe species: ecological and environmental determinants.

Plant spatial distribution is an important topic in ecology as it determines species coexistence and biodiversity dynamics. Usually, plants show clustered distributions in nature. Mistletoes are a good example of aggregated distributions, as they form dense aggregations due to several factors (availability of competent hosts, seed dispersal vectors, microclimate conditions). We analysed four native mistletoe species with divergent life histories and host ranges: Desmaria mutabilis and Tristerix corymbosus from the temperate rainforests of southern Chile; and Tristerix aphyllus and Tristerix verticillatus from the northern semi-desert zone. While T. corymbosus and T. verticillatus have a wide host range, T. aphyllus and D. mutabilis are specialists that can parasitize only a few plant species. We hypothesized that specialized species would be more aggregated due to ecological and environmental restrictions. We used heterogeneous Poisson models to quantify spatial aggregation. Three of the four mistletoe species were spatially clustered at both environments, with aggregation being stronger in the temperate rainforest of southern Chile and particularly in the host-specialist species. Our results suggest that environmental constraints are more important than ecological constraints (host range) in shaping mistletoe spatial structure. Mistletoe aggregated spatial distribution depends primarily on the environment that they inhabit, which conditions host spatial availability, and arrangement.

ß-2 agonists in sport: are the anti-doping rules meeting the needs of asthmatic athletes?

OBJECTIVES: (a) To review the methacholine tests performed in our laboratory up until 2008; (b) to compare them with previously reported data in 2006 and (c) to examine if the anti-doping rules are meeting the needs of asthmatic athletes who really need bronchodilator treatment. METHODS: Between April 2004 and September 2008, 89 high-level athletes were examined in our laboratory in order to obtain an abbreviated therapeutic use exemption for ß-2 agonists. Of these, 50 men (23.31 (7.05) years) and 23 women (20.68 (5.94) years) performed a methacholine inhalation test with increasing concentrations of methacholine (0.025, 0.25, 2.5, 5, 10 and 25 mg/ml) until a fall of 20% in forced expiratory volume in 1 s (FEV(1)) was achieved. RESULTS: 31 candidates (42.5%) had a provocative concentration causing a 20% fall in FEV(1) (PC(20)) <2 mg/ml; 12 (16.4%) were between 2 and 4 mg/ml; 8 (11%) between 4.1 and 8 mg/ml and 22 candidates (30.1%) had a PC(20) >8 mg/ml. Seven of the 73 candidates had an obstructive pattern in the spirometry at rest, demonstrated by a FEV(1)% <70% but with a FEV(1) >70% of the reference value. CONCLUSIONS: The anti-doping regulations with respect to ß-2 agonists need to be reviewed, and measures should be adopted to include a fall of 70% in FEV(1)% as an obstruction criterion to indicate a bronchodilation test and to extend the criterion for a positive methacholine test to a PC(20) of 8 mg/ml.

Result of the implementation of telematic consultations in orthopaedic surgery and traumatology during COVID-19 laparoscopic surgery. / Resultado de la implantación de consultas telemáticas en cirugía ortopédica y traumatología durante la pandemia COVID-19.

The COVID pandemic has made telematic consultations a basic tool in daily practice. AIMS: The main objective of the study is to assess the results of the application of telematic consultations to limit the mobility of patients. The operational objectives are; to propose a consultation plan, to know how attendance limits consultations and to define which pathologies benefit the most from this plan. METHODS: A scheme is proposed with the creation of pre-scheduled clinic to assess suitability and the possibility of carrying them out in a single non face-to-face act. RESULTS: Phone call to 5,619 patients were made with a lack of response of 19%. The cases of 74% of the patients that answered were resolved virtually. There is a difference between units, obtaining a higher answering rate from patients appointed to specific clinic units, OR = 0.60, or to general trauma ones, OR = 0.67. The lowest answering rate was obtained from those derived from the emergency department. Twenty per cent of the consultations were not accompanied by complementary tests that would have favored the resolution in a single act. The general trauma consultations, OR = 0.34, postoperative control, OR = 0.49, and specific unit ones, OR = 0.40, were the ones that better met this requirement. Out of the remaining patients, the general trauma consultations, OR = 0.50, and those referred to units, OR = 0.54, were the ones that had a higher resolution rate without in- person consultation. CONCLUSIONS: The cases of 74% of the patients who answered the phone call were resolved virtually. Cases of 20% of the patients cannot be solved in a single act because they are derived without complementary tests. Osteosynthesis and postoperative arthroscopic follow-up consultations are the ones that need to be carried out in person the most.

Identification of Peptides Potentially Responsible for In Vivo Hypolipidemic Activity of a Hydrolysate from Olive Seeds.

Previous studies demonstrated that peptides produced by the hydrolysis of olive seed proteins using Alcalase enzyme showed in vitro multifunctional lipid-lowering capability. This work presents a deeper insight into the hypolipidemic effect of olive seed peptides. The capability of olive seed peptides to inhibit endogenous cholesterol biosynthesis through the inhibition of HMG-CoA reductase enzyme was evaluated observing a 38 ± 7% of inhibition. Two in vivo assays using different peptides concentrations (200 and 400 mg/kg/day) were designed to evaluate the hypolipidemic effect of olive seed peptides in male and female mice. A low concentration of hydrolysate reduced total cholesterol in male mice in a 20% after 11 weeks compared to the mice feeding with hypercholesterolemic diet. A higher hydrolysate concentration showed a greater reduction in total cholesterol (25%). The analysis of the olive seed hydrolysate by reverse phase high-performance liquid chromatography mass spectrometry (RP-HPLC-MS) enabled the identification of peptides that could be responsible for this hypolipidemic effect.

Non-linear heart rate dynamics during and after three controlled exercise intensities in healthy men.

We aimed to analyse the complexity and fractal nature of heartbeat during constant exercise, at three different intensities, and recovery.Fourteen healthy men underwent 4 separate sessions. The first session was an incremental treadmill test to determine ventilatory thresholds (VT1 and VT2) and maximal aerobic speed (MAS). Each subject ran at VT1 and VT2 speeds and MAS (second, third and fourth day). The duration of VT1 and VT2 loads were selected in such a way that the product intensity-duration (training load) was the same. Sample Entropy (SampEn) and slope of Detrended Fluctuation Analysis (DFA α1) were measured during the whole session.DFA α1 declines with exercise, being less in the VT1 trial than in the other two.SampEn shows no significant change during exercise. The three tests induce the same decline in SampEn, but at the highest intensity (MAS) tends to decline during the exercise itself, whereas at lower intensities (VT1, VT2) the decline is delayed (10 min of recovery). Subsequently, SampEn at VT1 gradually recovers, whereas at VT2 and MAS it remains stable during recovery.In conclusion, exercise produces a loss of heartbeat complexity, but not fractal nature, during recovery and it depends on intensity.

Distribution of artificial radionuclides in deep sediments of the Mediterranean Sea.

Artificial radionuclides enter the Mediterranean Sea mainly through atmospheric deposition following nuclear weapons tests and the Chernobyl accident, but also through the river discharge of nuclear facility effluents. Previous studies of artificial radionuclides impact of the Mediterranean Sea have focussed on shallow, coastal sediments. However, deep sea sediments have the potential to store and accumulate pollutants, including artificial radionuclides. Deep sea marine sediment cores were collected from Mediterranean Sea abyssal plains (depth >2000 m) and analysed for (239,240)Pu and (137)Cs to elucidate the concentrations, inventories and sources of these radionuclides in the deepest areas of the Mediterranean. The activity - depth profiles of (210)Pb, together with (14)C dating, indicate that sediment mixing redistributes the artificial radionuclides within the first 2.5 cm of the sedimentary column. The excess (210)Pb inventory was used to normalize (239,240)Pu and (137)Cs inventories for variable sediment fluxes. The (239,240)Pu/(210)Pb(xs) ratio was uniform across the entire sea, with a mean value of 1.24x10(-3), indicating homogeneous fallout of (239,240)Pu. The (137)Cs/(210)Pb(xs) ratio showed differences between the eastern (0.049) and western basins (0.030), clearly significant impact of deep sea sediments from the Chernobyl accident. The inventory ratios of (239,240)Pu/(137)Cs were 0.041 and 0.025 in the western and eastern basins respectively, greater than the fallout ratio, 0.021, showing more efficient scavenging of (239,240)Pu in the water column and major sedimentation of (137)Cs in the eastern basin. Although areas with water depths of >2000 m constitute around 40% of the entire Mediterranean basin, the sediments in these regions only contained 2.7% of the (239,240)Pu and 0.95% of the (137)Cs deposited across the Sea in 2000. These data show that the accumulation of artificial radionuclides in deep Mediterranean environments is much lower than predicted by other studies from the analysis of continental shelf sediments.

Analysis of heart rate variability at rest and during aerobic exercise: a study in healthy people and cardiac patients.

OBJECTIVE: To analyse HRV at rest in healthy people and in patients with acute myocardial infarction (AMI) and how it changes during aerobic exercise. METHODS: The heartbeat signal was recorded beat to beat for 15 minutes at rest and 15 minutes while pedalling in 10 healthy and active men (H group) and 10 cardiac patients (C group). The statistical parameters in the time domain were calculated as well as the spectral analysis applying the Fast Fourier Transform (FFT) and Poincare's graphic analysis (PGA). RESULTS: At rest, H group have an average SDRR (standard deviation of RR intervals) of 71.24 msec, a pRR50 (percentage of differences higher than 50 msec in RR intervals) of 9.97% and a PGA called "comet-type". The C group have a SDRR of 36.69 msec, a pRR50 of 1.69%, and a PGA "torpedo-type". These data show a low or moderate risk for healthy people and a high risk for patients. The FFT analysis lies in the very-low-frequency (VLF) zone in both groups. During exercise, H group shows a significant decrease in all parameters; the PGA turns to "torpedo-type" and the FFT remains in the VLF zone. However, C group is characterised by the maintenance of pRR50, no change in PGA and a second peak in FFT in the high-frequency zone. CONCLUSION: The HRV at rest and during aerobic exercise follows a different pattern in healthy people and in patients and it provides further information about performance during exercise.

A new Certified Reference Material for radionuclides in Irish sea sediment (IAEA-385).

A new Certified Reference Material (CRM) for radionuclides in sediment (IAEA-385) is described and the results of the certification process are presented. Eleven radionuclides ((40)K, (137)Cs, (226)Ra, (228)Ra, (230)Th, (232)Th, (234)U, (238)U, (238)Pu, (239+240)Pu and (241)Am) have been certified and information mass activities with 95% confidence intervals are given for seven other radionuclides ((90)Sr, (210)Pb((210)Po), (235)U, (239)Pu, (240)Pu and (241)Pu). Results for less frequently reported radionuclides ((60)Co, (99)Tc, (134)Cs, (155)Eu, (224)Ra and (239)Np) and information on some activity and mass ratios are also reported. The CRM can be used for quality assurance/quality control of the analysis of radionuclides in sediment samples, for the development and validation of analytical methods and for training purposes.

Anthropogenic 236U and 129I in the Mediterranean Sea: First comprehensive distribution and constrain of their sources.

The first basin-wide distribution of 236U/238U atom ratios and 129I concentrations is presented for the Mediterranean Sea. During the GEOTRACES GA04S-MedSeA expedition in 2013 seawater was collected from 10 vertical profiles covering the principal sub-basins of the Mediterranean Sea. The main objective was to understand the distributions of 236U and 129I in relation to the water masses, and to constrain their sources in this region. The 236U/238U atom ratios and the 129I concentrations ranged from (710±40)×10-12 to (2220±60)×10-12 and from (4.0±0.1)×107 to (13.8±0.3)×107at·kg-1, respectively. The results show that radionuclide-poor Atlantic Water is entering at the surface through the Strait of Gibraltar whereas comparably radionuclide-enriched Levantine Intermediate Water is sinking in the Eastern Basin and flowing westward at intermediate depths. Low radionuclide levels were found in the oldest water masses at about 1000-2000m depth in the Eastern Basin. At greater depths, waters were relatively enriched in 236U and 129I due to dense water formation occurring in both, the Eastern and Western Basins. The inventories of 236U and 129I cannot be explained only by global fallout from atmospheric nuclear bomb testings carried out in the 1950s and 1960s. We estimate that the liquid input of 236U from the nuclear reprocessing facility of Marcoule (France), via the Rhône river, was of the same order of magnitude than the contribution from global fallout, whereas liquid and gaseous releases of 129I from Marcoule were up to two orders of magnitude higher than global fallout. For both radionuclides, the contribution from the Chernobyl accident is found to be minor.

Use of beta2 agonists in sport: are the present criteria right?

BACKGROUND: The regulations for doping control prohibit the use of beta2 agonist bronchodilators (salbutamol, salmeterol, formoterol, and terbutaline) unless the subject follows the procedure known as abbreviated therapeutic use exemption (ATUE). OBJECTIVE: To highlight how the interest in discovering possible cheats may result in damage to athletes who really need bronchodilator treatment. METHODS: Thirty one high level athletes (18 men and 13 women) with a previous diagnosis of asthma were examined in our laboratory in order to obtain an ATUE for beta2 agonists. All the subjects underwent spirometry at rest. If the results were normal, the subjects underwent an effort test and, if negative, a methacholine test inhaling progressive doses of methacholine until a fall of 20% in forced expiratory volume in one second (FEV1) was achieved. The international anti-doping regulations require that the fall in FEV1 occurs with a concentration of methacholine (PC20) lower than 2 mg/ml (4 mg/ml for Torino 2006). In clinical practice, a test is positive if the response occurs with a PC20 lower than 8 mg/ml. RESULTS: Only one subject met the criterion for the bronchodilation test at rest. The remaining 30 athletes underwent an effort test, which was positive in nine of them. In 21 cases (13 men and 8 women) the effort test was negative so a methacholine test was carried out. Seven (33%) were negative for ATUE with a PC20 higher than 8 mg/ml, seven (33%) were positive for ATUE with a PC20 less than 2 mg/ml, in four (19%) the PC20 was 2-4 mg/ml, and in three (14%) it was 4-8 mg/ml. CONCLUSIONS: Strict vigilance of fair play should be pursued, but excessive control can lead to situations of inequality for asthmatic athletes such that a third of athletes cannot be treated with beta2 agonists. Therefore under current regulations, asthmatic athletes are often denied the most effective therapeutic option.

Dose assessment to workers in a dicalcium phosphate production plant.

The production of dicalcium phosphate (DCP) uses phosphate rock (PR) as a raw material. Sedimentary phosphate rocks are enriched with relevant concentrations of natural radionuclides from the 238U decay chain (around 103 Bq·kg-1), leading to the need of controlling potential exposures to radiation of workers and members of the public in accordance with IAEA safety standards. Indeed, phosphate industries are classified as Naturally Occurring Radioactive Material (NORM) industries. Thus, the aim of this work is to assess the radiological risk of the workers in a DCP production plant located in the Iberian Peninsula (South-West Europe), which digests PR with hydrochloric acid. In the present study 238U, 230Th, 222Rn, 210Pb and 210Po concentrations in aerosols (indoor and outdoor areas) are reported. Aerosols showed concentrations between 0.42-92 mBq·m-3 for 238U, 0.24-33 mBq·m-3 for 230Th, 0.67-147 mBq·m-3 for 210Pb and 0.09-34 mBq·m-3 for 210Po. Long-term exposure (four months) of passive 222Rn detectors provided concentrations that ranged from detection limit (< DL) to 121 Bq·m-3 in outdoor areas and from < DL to 211 Bq·m-3 in indoor areas, similar to concentrations obtained from short-term measurements with active detectors from < DL to 117 Bq·m-3 in outdoor areas and from < DL to 318 Bq·m-3 in indoor places. 226Ra accumulation in ebonite and pipe scales were the most important contributions to the ambient dose equivalent H*(10), resulting in 0.07 (background)-27 µSv·h-1 with a median value of 1.1 µSv·h-1. Average 222Rn air concentrations were lower than the 300 Bq·m-3 limit and therefore, according to European Directive 2013/59/EURATOM, 222Rn concentration is excluded from the worker operational annual effective dose. Thus, considering the inhalation of aerosols and the external dose sources, the total effective dose determined for plant operators was 0.37 mSv·y-1.

Influence of submarine groundwater discharge on (210)Po and (210)Pb bioaccumulation in fish tissues.

This study presents the results of the accumulation of (210)Po and (210)Pb in fish tissues and organs in a brackish-water marshland that is characterized by high concentrations of (222)Rn and (226)Ra supplied by submarine groundwater discharge (SGD). Tissues and organs from Cyprinus carpio, Chelon labrosus and Carassius auratus in the wetland were significantly enriched by both (210)Pb and (210)Po (up to 55 and 66 times, respectively) compared to blanks. The major input route of (210)Pb and (210)Po into the fish body seems to be through ingestion, due to the high levels of (210)Pb and (210)Po found in the gut content as well as in organs involved in digestion and metabolism (i.e. gut, kidney and hepatopancreas). Results showed that (210)Po was more accumulated in all fish tissues and organs except for the spine, which showed a higher affinity for (210)Pb, due to its capacity to replace Ca from apatite in bones. Over all the variables analyzed, fish tissues/organs and, secondarily, fish species were the most important factors explaining the concentration of radionuclides, whereas fish length and the sampling location played a minor role. The relationship of the two radionuclides varied markedly among tissues and their concentration levels were only correlated in gills, gut and, marginally, in spines. In general, the highest values of (210)Pb and (210)Po concentrations in tissues were found on C. labrosus tissues rather C. auratus and C. carpio. This study demonstrates that inputs of natural radionuclides supplied by SGD to coastal semi-enclosed areas (such as marshlands, lagoons or ponds) may significantly increase the contents of (210)Pb and (210)Po in fish tissues/organs. Thus, this study represents one of the first evidences of direct ecological effects derived from SGD.

Chronic stress impairs acoustic conditioning more than visual conditioning in rats: morphological and behavioural evidence.

Chronic stress affects brain areas involved in learning and emotional responses. These alterations have been related with the development of cognitive deficits in major depression. The aim of this study was to determine the effect of chronic immobilization stress on the auditory and visual mesencephalic regions in the rat brain. We analyzed in Golgi preparations whether stress impairs the neuronal morphology of the inferior (auditory processing) and superior colliculi (visual processing). Afterward, we examined the effect of stress on acoustic and visual conditioning using an avoidance conditioning test. We found that stress induced dendritic atrophy in inferior colliculus neurons and did not affect neuronal morphology in the superior colliculus. Furthermore, stressed rats showed a stronger impairment in acoustic conditioning than in visual conditioning. Fifteen days post-stress the inferior colliculus neurons completely restored their dendritic structure, showing a high level of neural plasticity that is correlated with an improvement in acoustic learning. These results suggest that chronic stress has more deleterious effects in the subcortical auditory system than in the visual system and may affect the aversive system and fear-like behaviors. Our study opens a new approach to understand the pathophysiology of stress and stress-related disorders such as major depression.

Most of the homoeologous pairing at metaphase I in wheat-rye hybrids is not chiasmatic.

The use of telomeric C-bands in wheat-rye hybrids has made it possible to distinguish three types of wheat-wheat (1B(L)) and wheat-rye associations (a, end-to-end extremely distal; b, end-to-ed distal; and c, interstitial) between homoeologous chromosomes at different metaphase I stages (early, middle and late) and also to estimate the actual recombination frequencies for such associations at anaphase I. There was a decrease of the a and b association frequencies during the different metaphase I stages, whereas the c type remained without variation in all stages. A good fit between the frequencies of c associations at metaphase I and the number of recombinant chromosomes at anaphase I, assuming a maximum of one chiasma per bond, was found; however, there was no correspondence between metaphase I and anaphase I data when all associations (a + b + c) were considered. In addition, rye-rye homologous pairing was observed at metaphase I, but no evidence for rye-rye recombination was found at anaphase I. The results indicate that most of end-to-end (a and b) homoeologous and nonhomologous associations are actually nonchiasmatic and are a remnant of prophase pairing.

Chromosome differentiation and pairing behavior of polyploids: an assessment on preferential metaphase I associations in colchicine-induced autotetraploid hybrids within the genus Secale.

Preferential chromosome association at metaphase I has been analyzed and compared in autotetraploid cells obtained by colchicine treatment of hybrid diploid rye plants with different degrees of chromosomal divergence between homologs. The tendency to identical over homologous, but not identical, pairing preferences detected when homologous partners are contributed by less related parental lines indicates that chromosome differentiation may play an important role on preferential pairing behavior of polyploids. However, associations between more similar (identical) partners are not always favored, thus suggesting that additional factors must be considered. Other hypotheses for explaining pairing preferences in competitive situations are discussed. No clear relationship has been found between multivalent frequencies at metaphase I and chromosome differentiation between homologs or preferential pairing behavior. Therefore evolutionary divergences among related genomes should be carefully stated when evaluated from metaphase I configuration frequencies.

Pairing Competition between Identical and Homologous Chromosomes in Autotetraploid Rye. I. Submetacentric Chromosomes.

Meiotic pairing preferences between identical and homologous but not identical chromosomes were analyzed in ten induced tetraploid/diploid chimaeral rye plants (Secale cereale) heterozygous for telomeric heerochromatin C-bands in both arms of chromosome 1R. These plants were the progeny of two crosses between only one plant of cv. Petkus, used as male, and two plants of the inbred lines E and R, respectively. Different pairing preferences for chromosome 1R were found: (1) between plants, (2) between chromosome arms within the same plant and (3) between bivalents and multivalents within the same plant. The possible influence in the preferences of several factors such as differences in C-heterochromatin content in the chromosomes analyzed, specific genetic control and independence in pairing behavior between both arms and partner exchange is discussed.

Pairing Competition between Identical and Homologous Chromosomes in Rye and Grasshoppers.

Meiotic pairing preferences between identical and homologous but not identical chromosomes were analyzed in spontaneous tetraploid/diploid chimeras of three male grasshoppers (Eyprepocnemis plorans) whose chromosome pair 11 were heterozygous for C-banding pattern and in four induced tetraploid/diploid chimaeral rye plants (Secale cereale) heterozygous for telomeric heterochromatin C-bands in chromosomes 1R and 2R. In the grasshoppers, a preference for identical over homologous pairing was observed, whereas in rye both a preference for homologous rather than identical pairing and random pairing between the four chromosomes of the set was found. From the results in rye, it can be deduced that pairing preferences do not depend exclusively on the similarities between chromosomes involved. It is suggested that genotypic or cryptic structural differences between the homologous chromosomes of each pair analyzed might be responsible for the pairing preferences found. This hypothesis can also explain the results obtained in grasshoppers, although the possibility of premeiotic association cannot be excluded in this material.

[Diagnosis of complex congenital heart disease through magnetic resonance]. / Diagnóstico de las cardiopatías congénitas complejas por resonancia magnética.

OBJECTIVE: To analyze the usefulness of magnetic resonance for the morphological diagnosis in complex congenital cardiopathies and compare it with the transthoracic echocardiogram. METHOD: We included 45 patients with clinical suspicion of severe congenital cardiopathy. A magnetic resonance and a transthoracic echocardiogram were performed and the anatomy and size of the cardiac cavities were compared. Descriptive statistics were used and Bland-Altman test was used to analyze concordance between both methods. RESULTS: There were no significant differences in the measures obtained with either method, except for the left ventricle ejection fraction (66.56 +/- 9.47 with ECO vs 52.32 +/- 13.85 with MR, p = 0.0001) and for diameter of the left branch of the pulmonary artery (9.77 +/- 6.80 with ECO vs 12.83 +/- 8.46 with MR, p = 0.05). The sensitivity, specificity, and predictive values of MR were high to analyze the AV and VA connection, but not for the atrial sinus and the venous drainages (pulmonary and systemic). Concordance of ejection fraction measures, McGoon index, and size of VD revealed few extreme values. CONCLUSIONS: MR and ECO are similar for the morphological diagnosis of severe congenital cardiopathies, but MR can be better than ECO for the visualization of extracardiac structures.