In-plane reorientation induced single laser pulse magnetization reversal.

Single Pulse All Optical Switching represents the ability to reverse the magnetization of a nanostructure using a femtosecond single laser pulse without any applied field. Since the first switching experiments carried out on GdFeCo ferrimagnets, this phenomena has been only recently extended to a few other materials, MnRuGa alloys and Tb/Co multilayers with a very specific range of thickness and composition. Here, we demonstrate that single pulse switching can be obtained for a large range of rare earth-transition metal multilayers, making this phenomenon much more general. Surprisingly, the threshold fluence for switching is observed to be independent of the laser pulse duration. Moreover, at high laser intensities, concentric ring domain structures are induced. These striking features contrast to those observed in Gd based materials pointing towards a different reversal mechanism. Concomitant with the demonstration of an in-plane magnetization reorientation, a precessional reversal mechanism explains all the observed features.

Spintronic memristors for neuromorphic circuits based on the angular variation of tunnel magnetoresistance.

In this study, a new type of compact magnetic memristor is demonstrated. It is based on the variation of the conductivity of a nano-sized magnetic tunnel junction as a function of the angle between the in-plane reference layer magnetization and a free layer exhibiting an isotropic in-plane coercivity. The free layer magnetization is rotated by two spin transfer torque contributions: one originating from the in-plane magnetized reference layer and the other one from an additional perpendicular polarizer integrated in the stack. Thanks to a proper tuning of the relative influence of these two torques, the magnetization of the free layer can be rotated step by step clockwise or anticlockwise in a range of angle between 0° (parallel configuration) and 180° (anti-parallel configuration) by sending pulses of current through the stack, of one or opposite polarity. The amplitude of the rotation steps and therefore of the conductance variations depends on the pulse amplitude and duration. In this way, we achieve monotonous variations of the resistance with the voltage polarity through the application of pulses in the ns range. We also retrieve the analytical expression of critical current density which is found to be in good agreement with the experimental results. The thermal stability of the intermediate resistance levels and the role of Joule heating are also discussed.

All-optical spin switching probability in [Tb/Co] multilayers.

Since the first experimental observation of all-optical switching phenomena, intensive research has been focused on finding suitable magnetic systems that can be integrated as storage elements within spintronic devices and whose magnetization can be controlled through ultra-short single laser pulses. We report here atomistic spin simulations of all-optical switching in multilayered structures alternating n monolayers of Tb and m monolayers of Co. By using a two temperature model, we numerically calculate the thermal variation of the magnetization of each sublattice as well as the magnetization dynamics of [[Formula: see text]/[Formula: see text]] multilayers upon incidence of a single laser pulse. In particular, the condition to observe thermally-induced magnetization switching is investigated upon varying systematically both the composition of the sample (n,m) and the laser fluence. The samples with one monolayer of Tb as [[Formula: see text]/[Formula: see text]] and [[Formula: see text]/[Formula: see text]] are showing thermally induced magnetization switching above a fluence threshold. The reversal mechanism is mediated by the residual magnetization of the Tb lattice while the Co is fully demagnetized in agreement with the models developed for ferrimagnetic alloys. The switching is however not fully deterministic but the error rate can be tuned by the damping parameter. Increasing the number of monolayers the switching becomes completely stochastic. The intermixing at the Tb/Co interfaces appears to be a promising way to reduce the stochasticity. These results predict for the first time the possibility of TIMS in [Tb/Co] multilayers and suggest the occurrence of sub-picosecond magnetization reversal using single laser pulses.

Indium Tin Oxide optical access for magnetic tunnel junctions in hybrid spintronic-photonic circuits.

The all-optical magnetization reversal of magnetic layers, by picosecond optical pulses, is of particular interest as it shows the potential for energy-efficient and fast magnetic tunnel junction (MTJ) elements. This approach requires memory elements that are optically and electronically accessible, for optical writing and electronic read-out. In this paper, we propose the integration of indium tin oxide (ITO) as a transparent conducting electrode for magnetic tunnel junctions in integrated spintronic-photonic circuits. To provide light with sufficient energy to the MTJ free layer and allow electrical read-out of the MTJ state, we successfully integrated indium tin oxide as a top transparent electrode. The study shows that ITO film deposition by physical vapor deposition with conditions such as high source power and low O2 flow achieves smooth and conductive thin films. Increase in grain size was associated with low resistivity. Deposition of 150 nm ITO at 300 W, O2 flow of 1 sccm and 8.10-3 mbar vacuum pressure results in 4.8 × 10-4 Ω.cm resistivity and up to 80% transmittance at 800 nm wavelength. The patterning of ITO using CH4/H2 chemistry in a reactive ion etch process was investigated showing almost vertical sidewalls for diameters down to 50 nm. The ITO based process flow was compared to a standard magnetic tunnel junctions fabrication process flow based on Ta hard mask. Electrical measurements validate that the proposed process based on ITO results in properties equivalent to the standard process. We also show electrical results of magnetic tunnel junctions having all-optical switching top electrode fabricated with ITO for optical access. The developed ITO process flow shows very promising initial results and provides a way to fabricate these new devices to integrate all-optical switching magnetic tunnel junctions with electronic and photonic elements.

Single-shot all-optical switching of magnetization in Tb/Co multilayer-based electrodes.

Ever since the first observation of all-optical switching of magnetization in the ferrimagnetic alloy GdFeCo using femtosecond laser pulses, there has been significant interest in exploiting this process for data-recording applications. In particular, the ultrafast speed of the magnetic reversal can enable the writing speeds associated with magnetic memory devices to be potentially pushed towards THz frequencies. This work reports the development of perpendicular magnetic tunnel junctions incorporating a stack of Tb/Co nanolayers whose magnetization can be all-optically controlled via helicity-independent single-shot switching. Toggling of the magnetization of the Tb/Co electrode was achieved using either 60 femtosecond-long or 5 picosecond-long laser pulses, with incident fluences down to 3.5 mJ/cm2, for Co-rich compositions of the stack either in isolation or coupled to a CoFeB-electrode/MgO-barrier tunnel-junction stack. Successful switching of the CoFeB-[Tb/Co] electrodes was obtained even after annealing at 250 °C. After integration of the [Tb/Co]-based electrodes within perpendicular magnetic tunnel junctions yielded a maximum tunneling magnetoresistance signal of 41% and RxA value of 150 Ωµm2 with current-in-plane measurements and ratios between 28% and 38% in nanopatterned pillars. These results represent a breakthrough for the development of perpendicular magnetic tunnel junctions controllable using single laser pulses, and offer a technologically-viable path towards the realization of hybrid spintronic-photonic systems featuring THz switching speeds.

Thermal robustness of magnetic tunnel junctions with perpendicular shape anisotropy.

The concept of Perpendicular Shape Anisotropy STT-MRAM (PSA-STT-MRAM) has been recently proposed as a solution to enable the downsize scalability of STT-MRAM devices beyond the sub-20 nm technology node. For conventional p-STT-MRAM devices with sub-20 nm diameters, the perpendicular anisotropy arising from the MgO/CoFeB interface becomes too weak to ensure thermal stability of the storage layer. In addition, this interfacial anisotropy rapidly decreases with increasing temperature which constitutes a drawback in applications with a large range of operating temperatures. Here, we show that by using a PSA based storage layer, the source of anisotropy is much more robust against thermal fluctuations than the interfacial anisotropy, which allows considerable reduction of the temperature dependence of the coercivity. From a practical point of view, this is very interesting for applications having to operate on a wide range of temperatures (e.g. automotive -40 °C/+150 °C).

A highly thermally stable sub-20 nm magnetic random-access memory based on perpendicular shape anisotropy.

A new approach to increase the downsize scalability of perpendicular STT-MRAM is presented. It consists of significantly increasing the thickness of the storage layer in out-of-plane magnetized tunnel junctions (pMTJ) as compared to conventional pMTJ in order to induce a perpendicular shape anisotropy (PSA) in this layer. This PSA is obtained by depositing a thick ferromagnetic (FM) layer on top of an MgO/FeCoB based magnetic tunnel junction (MTJ) so that the thickness of the storage layer is of the order of or larger than the diameter of the MTJ pillar. In contrast to conventional spin transfer torque magnetic random access memory (STT-MRAM) wherein the demagnetizing energy opposes the interfacial perpendicular magnetic anisotropy (iPMA), in these novel memory cells, both PSA and iPMA contributions favor the out-of-plane orientation of the storage layer magnetization. Using thicker storage layers in these PSA-STT-MRAMs has several advantages. Due to the PSA, very high and easily tunable thermal stability factors can be achieved, even down to sub-10 nm diameters. Moreover, a low damping material can be used for the thick FM material thus leading to a reduction of the write current. The paper describes this new PSA-STT-MRAM concept, practical realization of such memory arrays, magnetic characterization demonstrating thermal stability factor above 200 for MTJs as small as 8 nm in diameter and possibility to maintain the thermal stability factor above 60 down to 4 nm diameter.

Using atmospheric plasma to increase wettability, imbibition and germination of physically dormant seeds of Mimosa Caesalpiniafolia.

In this study, we analyzed seed wettability as well as imbibition and germination after treatment with atmospheric pressure cold plasma (APCP) using dielectric barrier discharge (DBD) in seeds that have very low germination rates. To aid industrial applications, several seeds were simultaneously treated with plasma within a space between two coaxial glass tubes sandwiched by two metal mesh screens that produced high-voltage pulses at 17.5kV with a frequency of 990Hz. Three treatment times (3min, 9min and 15min) as well as untreated seeds were used to conduct the wettability, imbibition and germination tests. The wettability and imbibition were found to be directly related to the treatment duration, but saturation of the imbibition was found for treatment durations greater than 9min. Plasma treatment was also effective in improving germination, but shorter treatment duration presented greater germination. This apparent contradiction is explained by the cell damage caused by the increased exposure to plasma, as observed in other studies. The results suggest that there must be an optimal wettability and imbibition condition that ensures that excessive moisture does not harm the germination process.

High-resolution electrocardiography in dogs under doxorubicin-induced cardiomyopathy / Eletrocardiografia de alta resolução em cães com cardiomiopatia induzida pela doxorrubicina

The occurrence of late potentials in dogs under doxorubicin-induced cardiomyopathy and their relationship with the development of ventricular arrhythmias or sudden death were studied. Seven adult mongrel dogs of both sexes were used. Cardiomyopathy was induced by slow intravenous infusion of doxorubicin (30mg/m²) at 21-day intervals, until a total cumulative dose of 240mg/m² was reached. Animals were monitored by echocardiography. After the induction of cardiomyopathy, high-resolution electrocardiography was recorded. Late potentials were observed in two animals that suddenly died a few days later.

Determinaram-se a ocorrência de potencial tardio em cães com cardiomiopatia induzida pela doxorrubicina e sua relação com o desenvolvimento de arritmias ventriculares ou morte súbita. Sete cães adultos, sem raça definida, de ambos os sexos foram utilizados. A cardiomiopatia foi induzida por infusão venosa lenta de doxorrubicina (30mg/m²) em intervalos de 21 dias, até uma dose total cumulativa de 240mg/m². Os animais foram monitorados ecocardiograficamente. Após a confirmação da cardiomiopatia, foi feito o registro da eletrocardiografia de alta resolução. Potenciais tardios foram observados em dois animais que morreram subitamente poucos dias após.

A clinical report of bone regeneration in maxillofacial surgery using bonelike synthetic bone graft.

The objective of this study is to evaluate the osteoconductivity and bioactivity of the Bonelike graft in repairing surgical cystic bone defects. Bonelike is implanted in 11 patients, aged between 24 and 53 years with a mean age of 36 years, consisting of 5 men and 6 women. According to the standard follow up protocols, radiological examinations are performed and Bonelike/bone retrieved samples have been analyzed histologically using non-decalcified sections obtained perpendicular to bone length axis. Radiographic examination and histological results clearly demonstrate an extensive new bone formation apposed on Bonelike granules with a significant degree of maturation. These clinical applications in maxillary bone defects indicate perfect bone bonding between new bone formed and Bonelike granules, along with partial surface biodegradation. This quick and effective osteoconductive response from Bonelike may reduce the time needed to reconstruct the bone defected area of patients.

Phase coherent precessional magnetization reversal in microscopic spin valve elements.

We evidence multiple coherent precessional magnetization reversal in microscopic spin valves. Stable, reversible, and highly efficient magnetization switching is triggered by transverse field pulses as short as 140 ps with energies down to 15 pJ. At high fields a phase coherent reversal is found revealing periodic transitions from switching to nonswitching under variation of pulse parameters. At the low field limit the existence of a relaxation dominated regime is established allowing switching by pulse amplitudes below the quasistatic switching threshold.

Quasiballistic magnetization reversal.

We demonstrate a quasiballistic switching of the magnetization in a microscopic magnetoresistive memory cell. By means of time resolved magnetotransport, we follow the large angle precession of the free layer magnetization of a spin valve cell upon application of transverse magnetic field pulses. Stopping the field pulse after a 180 degrees precession rotation leads to magnetization reversal with reversal times as short as 165 ps. This switching mode represents the fundamental ultrafast limit of field induced magnetization reversal.

Morphometric changes associated with sex and development in the Malpighian tubules of Aedes aegypti.

The Malpighian tubules of Aedes aegypti showed significant differences in their diameters between male and female larvae, male and female pupae, male larvae and male adults and male pupae and male adults. In every case, female values were greater than in males. Measurements of mean nuclear areas of the principal and stellate cells from Malpighian tubules, taken in males and females during development, showed that this parameter in both types of cell was significantly greater in females than in male larvae, pupae and adult stages. In males, significant differences between developmental stages were observed only in comparison with the nuclear area of larvae and adults in the principal cells, but in females, every comparison between stages showed significant differences except between pupae and adults in stellate cells. The frequency distribution of nuclear area values, in development, for male stellate and principal cells, were mostly concentrated in the first seven classes among the 30 classes considered in every stage, while for females, the frequency dropped drastically in the same classes from larvae to pupae and adults, moving to classes of higher values. Considering the importance of Malpighian tubules in insect physiology, the meaning of the differences detected are discussed on the basis of different metabolic levels, between sexes and developmental stages.

[Benign prostatic hyperplasia. Guidelines and recommendations in urological clinical practice]. / Hiperplasia benigna da prostata. Orientações e recomendações na prática clínica urológica.

After reviewing the clinical, diagnostic and therapeutic attitudes related to benign prostatic hyperplasia, the authors present guidelines for generalists in what concerns practical attitudes and when and how to refer their patients to the urologist. Based on the criteria presented, generalists must refer their patients to a urologist in the presence of mild or severe symptoms, ages below 50, diabetes or neurological perturbations, dysfunctional voiding, palpable bladder, palpable nodule or a diffusely hardened or asymmetric gland revealed by digital rectal examination, haematuria, urinary tract infection, renal impairment or PSA above 4 ng/ml in patients under 70 years of age.

[The echocardiographic assessment of wall regurgitant jets in prosthetic mitral valves: the superiority of multiplanar transesophageal sections over standard sections]. / Valoración ecocardiográfica de los jets regurgitantes de pared en válvulas protésicas mitrales: superioridad de las secciones transesofágicas multiplanares sobre las secciones estándares.

OBJECTIVES: The purpose of this study was to determine whether multiplanar (MP) transesophageal echocardiographic views were superior to standard views (ST), in the evaluation of mitral prosthesis regurgitation (MR), particularly in presence of wall regurgitant jets. METHODS: We studied all mitral prostheses (n = 43) in which pathological mitral regurgitation had been detected by multiplanar TEE between January 1993 and March 1994. Regurgitant prostheses were classified in two groups according to the presence of wall regurgitant jets and maximum turbulent color flow areas (Amax.) were measured on standard (0 and 90 degrees) and MP (0 to 180 degrees) views. RESULTS: The Amax. detected on ST views were 5.80 +/- 4.60 cm2 and on MP 7.42 +/- 5.13 cm2. Student's test was used to compare both areas and significant differences were found: 1.61 cm2; 95% confidence interval from 0.94 to 2.28 cm2; p = 0.000025. The sample was divided in two groups, A (n = 33): with wall jets and B (n = 10): without wall jets. The Amax. for group A was 5.64 +/- 4.30 cm2 in ST views, and 7.51 +/- 5.12 cm2 in MP. The difference was statistically significant: 1.86 cm2, 95% c.i. from 1.04 to 2.68 cm2; p = 0.00009. Differences for group B were also statistically significant: 0.68 cm2; p = 0.0172. MP views detected a bigger regurgitant area in 26 of the 43 cases (60%). The difference between ST and MP views was significantly bigger for group A than for group B: mean 1.18 cm2; p = 0.0176. MP views detected a severer degree of MR, classified as mild moderate and severe according to the color flow area, than ST views in 8 patients. All of them had wall regurgitant jets. Three had been considered normal on ST views. CONCLUSION: We conclude that MP transesophageal views are significantly superior to ST in the assessment of regurgitant prosthetic mitral valves, particularly in presence of wall regurgitant jets. Our data strongly suggest that multiplanar TEE is the procedure of choice in the assessment of wall regurgitant mitral prostheses.

[Mitral valve with double orifice. Report of a clinical case]. / Válvula mitral com duplo orifício. A propósito de um caso clínico.

Double mitral valve orifice is an uncommon congenital heart defect. The isolated occurrence of this anomaly is exceptional and, more often, is encountered in association with other congenital cardiac abnormalities. We present a case of a functionally normal double mitral valve orifice, an "incomplete bridge" type, diagnosed by two-dimensional transthoracic echocardiography in a ten years old patient. Due to its rarity we have reviewed and discussed this entity and the echocardiographic features of its types.

[The contribution and usefulness of routine intraoperative transesophageal echocardiography in cardiac surgery. An analysis of 130 consecutive cases]. / Contributo e rentabilidade da ecocardiografia transesofágica intraoperatória de rotina em cirurgia cardíaca. Análise de 130 casos consecutivos.

PURPOSE: To assess the value of routine intraoperative transesophageal echocardiography (TEE) in unselected patients (P) undergoing cardiac surgery. DESIGN: Routine intraoperative TEE in unselected patients undergoing cardiac surgery and evaluation of its usefulness and contribute to a successful surgery. PATIENTS: In-hospital patients from cardiology, cardiac surgery and intensive care departments of a general hospital classified as a reference medical centre in cardiovascular pathology. MATERIAL AND METHODS: From February 1994 to May 1994 an intraoperative TEE was routinely performed in patients undergoing cardiac surgery. A total of 130 TEE studies were made corresponding to 128 patients, 69 males and 61 females, with a mean age of 49.4 +/- 12.1 years. Indications for surgery were as following: a) Coronary artery bypass grafting (C.A.B.G.)-39; b) Valvular surgery-76; c) C.A.B.G. and valvular surgery-5; d) Thoracic aorta pathology associated or not to aortic valve surgery and/or coronary arteries re-implantation-6; e) Other-4. TEE performed using either a monoplane, biplane or multiplane probe and the images acquisition was made before thoracotomy and cardiopulmonary bypass (CPB) and after CPB with hemodynamic stabilization. RESULTS: Pre CPB imaging yielded unsuspected findings in 11 P (8.5%) that changed the planned surgery in 7 cases (5.4%). Post CPB echo study, which was performed after hemodynamic stabilization, modified the surgical strategy in 13 cases (10.9%) avoiding 1 predetermined surgical procedure (tricuspid ring annuloplasty) and a new surgery in another case, leading to a 3 non-predetermined surgical procedures (by showing significative tricuspid regurgitation), to a further surgery in the same valve in 6 patients (mitral paravalvular leak with significative regurgitation in 1P, another mitral prosthesis dysfunction in 1P, residual mitral valve insufficiency after mitral valve repair in 3 P and aortic prosthesis dysfunction in 1 P), to a intraaortic counterpulsation balloon device in 1 P and to new CPB due to an insufficient extraction of calcified pericardium in one case of constrictive pericarditis. In 23 cases (17.7%) TEE has modified the anesthetic procedure by demonstrating signs of hemodynamic changes before Swan-Ganz catheter, thus prompting changes in the administrations of fluids and either in inotropic or vasodilator agents. In total, intraoperative TEE has changed the surgical and/or anesthetic plan in 43 cases (33.0%). There was no difficulties or complications related to the procedure. CONCLUSION: These data indicate that intraoperative TEE is useful in formulating the surgical plan and assessing immediate operative results as well as a guide to anesthetic procedures. Its high rentabillity in modifying the surgical and/or anesthetic plans lead us to believe that it must be used as a routine procedure in patients undergoing cardiac surgery.

[Transesophageal echocardiography assessment of regurgitant jets of eccentric geometry in mitral valve prosthesis: superiority of multiplanar sections over standard sections]. / Avaliação por ecocardiografia transesofágica dos jactos regurgitantes de geometria excêntrica em válvulas protésicas mitrais: superioridade das secções de corte multiplanares sobre as secções standard.

OBJECTIVE: The purpose of this study was to determine whether multiplanar (MP) transesophageal echocardiographic views were superior to standard views (ST) at 0 degree and 90 degrees in the evaluation of mitral prosthesis regurgitation (MR), particularly in presence of wall regurgitant jets. DESIGN: Comparison between MP and ST views in the evaluation of mitral prosthesis regurgitation. SETTING: Laboratory of Echocardiography of the General Hospital Gregorio Marañon. MATERIAL AND METHODS: Study of all mitral prostheses in which pathological mitral regurgitation had been detected by multiplanar TEE, between January 1993 and March 1994. Regurgitation prosthesis were classified in two groups according to the presence of wall regurgitation jets and maximum turbulent color flow areas (MAX) were measured on standard (0 degree and 90 degrees) and MP (0 degree to 180 degrees) views. The sample was divided in two groups, A (n = 33): with wall jets and B (n = 10): without wall jets. Students' t test was used to compare both areas using a 95% confidence interval (95% c.i.). RESULTS: MAX detected on ST views were of 5.80 +/- 4.60 cm2 and on MP were of 7.42 +/- 5.13 cm2 being the difference statistically significant: 1.61 cm2, 95% c.i. from 0.94 to 2.28 cm2, p = 0.000025. MAX for group A was of 5.64 +/- 4.30 cm2 in ST views and of 7.51 +/- 5.12 cm2 in MP views, being the difference 1.86 cm2, 95% c.i. from 1.04 to 2.68; p = 0.00009. Differences for group B were also statistically significant: 0.68 cm2, p = 0.0176. Mitral regurgitation (MR) was classified as mild, moderate and severe according to the color flow area. MP views detected a severer degree of MR than ST views in 8 patients, all of them with wall regurgitation jets. Three of these cases had been considered normal on ST views. CONCLUSIONS: Multiplanar transesophageal views are significantly superior to standard views in the assessment of regurgitant prosthetic mitral valves, particularly in presence of wall regurgitant jets. Our data strongly suggest that multiplanar TEE is the procedure of choice in the assessment of wall regurgitant mitral prostheses.

[Value of transesophageal echocardiography in the assessment of blunt chest trauma: correlation with electrocardiogram, heart enzymes, and transthoracic echocardiogram]. / Valor da ecocardiografia transesofágica na avaliação de doentes com traumatismo torácico fechado: correlação com o electrocardiograma, enzimas cardíacas e ecocardiograma transtorácico.

OBJECTIVE: To asses the feasibility, usefulness and clinical rentability of the transesophageal echocardiography (TEE) in the evaluation of patients suffering a severe blunt chest trauma as well as to correlate the TEE findings with those provided by the conventional electrocardiogram (ECG), cardiac isoenzymes assay and transthoracic echocardiography (TTE). DESIGN: Prospective study using ECG, blood cardiac enzymes assay, TTE and TEE. SETTING: Intensive care unit of a general hospital. PATIENTS: We studied 34 patients admitted with blunt chest trauma and suspected cardiac contusion in spite of the existence of other traumatic injuries in some of them. There were 23 (67.6%) males and 11 females, with a mean age of 37.1 +/- 19.4 years (range: 16-69 years). MATERIAL AND METHODS: Patients with a previous history of cardiovascular or chronic pulmonary disease, cardiac arrest upon admission or positive cocaine or amphetamine levels in the urine were excluded from the study. Suspected cardiac contusion was established by clinical data, electrocardiographic findings, enzymes blood values (CPK-total and MB-fraction) and TTE findings. Additionally, a TEE was performed in each patient. Patients were stratified into two groups according to the TEE findings: Group A patients had signs compatible with cardiac contusion and in Group B patients there was a lack of evidence to substantiate this diagnosis. Those tests were evaluated in respect to their accuracy in the diagnosis of cardiac contusion when compared to transesophageal echocardiography and TEE findings were compared, whenever possible, to surgical or necropsic findings. RESULTS: We found TEE signs of cardiac injury in 22 (64.7%) patients and a wide spectrum of traumatic cardiac abnormalities were identified. TEE signs of ventricular injury were found in 15 pts of Group A (68.2%) being the right ventricle the most frequent affected. There were also two cases of mitral leaflet rupture, one case of tricuspid valve prolapse (with severe tricuspid regurgitation and associated with right ventricle wall motion abnormalities) and seven cases of pericardial effusion as well as one case of thoracic aortic dissection. In every patient submitted to cardiothoracic surgery or necropsy the TEE findings were confirmed. TEE provided significant information, sometimes crucial, to the patient evaluation and management, it was performed without any difficulty and it doesn't carried out any related complication. TTE was technically suboptimal in 53% and fail to demonstrate many cases of cardiac contusion and the thoracic aorta lesion, being the number of cardiovascular injuries demonstrated by TEE significantly higher (p = 0.029). No statistically significant difference was found between the number of patients with either an abnormal ECG or high values of CPK-MB in each group. Neither clinical findings, cardiac enzymes values, serial ECG's nor TTE predicted all the patients who had traumatic cardiac injury and those would subsequently developed complications related to cardiac contusion. CONCLUSIONS: A severe blunt chest trauma frequently results in cardiac injury. The ECG and the CPK-MB measurements appears both to be fairly sensitive and specific tests in the cardiac contusion diagnosis. TTE has shown to have important limitations in these patients, thus not allowing neither a complete echo evaluation nor a reliable one. TEE plays an important role in the evaluation and management of this type of patients providing rapid diagnostic information and being of high value in the rule out cardiac contusion as well as in the establishment of a specific diagnosis of cardiac and/or thoracic aorta injuries with a consequent better assessment and treatment strategy in these patients.

[Multiplanar transesophageal echocardiography: technique, methodology, and applications]. / Ecocardiografia transesofágica multiplano: técnica, metodologia e aplicações.

OBJECTIVE: To present the experience of transesophageal echocardiography with a multiplane probe, its methodology, the advantages, disadvantages and diagnostic improvements of this type of probe. SETTING: Laboratory of Echocardiography of the General Hospital Gregorio Marañon. MATERIAL AND METHODS: Analysis of the first 1000 examinations performed on hospitalized patients and outpatients, in most cases to study either native valvular heart disease and valvular prosthesis or to search for embolic sources. We evaluate the advantages, disadvantages, initial difficulties and complications of this type of probe. RESULTS: Multiplane probe provides continuous imaging from 0 degree to 180 degrees without need of intraesophagic movements. This type of probe increases the diagnostic capability of transesophagic echocardiography because it performs as a scanning of anatomy and pathological features of cardiac chambers and great vessels. Pulmonary artery and its branches, right heart chambers and tricuspid valve, inferior and superior vena cava, outflow tract of both ventricles, aortic root, pulmonary veins and segmental views of both ventricles are well analyzed. Also in native and prosthetic regurgitants jets, cardiac tumors and other masses, diagnosis and complications of endocarditis, aortic dissection and in anomalous return of pulmonary veins, multiplane probe proves to be more informative. There was no difficulties in the intubation despite the bigger size of the transducer. No severe complications occurred. The higher price and the initial more difficult understanding of the images are the only disadvantages we have found. CONCLUSIONS: Multiplane probe contributes to increase diagnostic capability of transesophageal echocardiography without significant risk and it is an important and promising refinement of the transesophageal technique.