The Biomed caged-ball cardiac valve prosthesis. A study of 120 implants.

The purpose of this study was to report our experience with 120 prosthetic valves implanted in 105 patients over an 8-year period. Their preoperative status was compared at an average follow-up period of 4 years (range 1 to 6 years) with the postoperative results. We conclude that the Mexican-made valves (Biomed) meet the highest international quality standards: they are well tolerated by the patients; their performance is excellent and no postoperative dysfunction of the valves was ever detected. The few complications observed were no different from those reported for foreign ball-caged valves. Finally, most of our patients showed a marked improvement postoperatively.

[An evaluation of the efficacy of nitrates (transdermal and peroral) in the management of the patient with a myocardial contusion]. / Valoración de la eficacia de los nitratos (transdérmicos y por vía oral) en el manejo del paciente con contusión miocárdica.

Although thoracic trauma is frequently accompanied by myocardial injury; this later is often oversighted at early stages of trauma and misdiagnosed by the time complications are present. Myocardial abnormalities have been attributed to a reduction of cardiac flow. Nitroglycerin and isosorbide dinitrate, both agents with a known vasodilator effect on coronary arteries, might improve myocardial ischemic resulting from traumatic contusion. In order to compare safety and efficacy between two nitrates and placebo on myocardial contusion resulting from thoracic trauma, we carried out a comparative, prospective, single blind study. Subjects were randomly allocated to one of the following 3 groups: a) transdermal nitroglycerin, b) isosorbide dinitrate and c) placebo. Medication was dispensed for five days. Major endpoint were electrocardiographic abnormalities at entry and their final modifications. Other were severity injury score and myocardial enzyme levels. Twelve patients were included in each group. Four measured enzymes were high at entry, but MB fraction in the nitroglycerin group showed the most rapid normalization. Creatine phosphokinase and lactic dehydrogenase significantly correlated with severity injury index, but not MB fraction. Electrocardiographic normalization was mainly observed in the nitroglycerin group. Transdermal nitroglycerin systems demonstrated to be effective on recovering from electrocardiographic abnormalities resulting of myocardial contusion.

Estudio de las características de flujo en tres tipos de prótesis valvulares cardiacas / Study of the characteristics of the flow in three types of cardiac valvular prosthesis

La turbulencia causada por el flujo transvalvular después de la implantación de una prótesis valvular, es una causa de la formación de trombos en la región postvalvular. La revisión de la literatura al respecto indica que hay mayor frecuencia de accidentes tromboembólicos en las válvulas cardiacas mecánicas de disco oscilante. Con el objeto de determinar la turbulencia que provoca una bioprótesis valvular porcina, una mecánica de esfera Biomed y un equipo para visualizar y fotografiar las características de flujo en las tres válvulas, destinado a visualizar la turbulencia. Se construyó también un equipo accesorio para medir la presión estática y dinámica en varios puntos de la probeta que contiene la prótesis, donde los cambios de presión muestran la turbulencia. Los datos obtenidos en unas 500 tomas de presión se analizaron en una computadora. Estos datos indican que la válvula biológica porcina origina poca turbulencia, en tanto que las mecánicas la provocan en mayor grado. De las mecánicas, la de disco oscilante causa una turbulencia considerablemente mayor que la de esfera y sobre todo, en la vecindad del orificio menor(au)

[Flow characteristics in 3 kinds of heart valve prosthesis]. / Estudio de las características de flujo en tres tipos de prótesis valvulares cardíacas.

Transvalvular turbulence caused by the blood flow in implanted cardiac valvular prosthesis is the cause of thrombosis at the post-valvular region. The literature in this connection indicates that thromboembolic complications are more common with the tilting disc mechanical valves. In order to study the turbulence caused by porcine biological prosthetic valves, by a caged-ball Biomed mechanical valve and by a tilting disc Björk-Shiley valve, a device was developed which permits to visualize and to photograph flow characteristics in the three types of valves with the purpose of determining the degree of turbulence generated in each case. An additional accessory equipment was devised for the purpose of measuring static and dynamic pressures at various levels of the test tube containing the prosthetic valve wherein the variations in pressure reflect the degree of turbulence. The data obtained from 500 pressure registrations were analyzed in a computer. The data indicate that the porcine biological valve causes the least turbulence, whereas the mechanical valves create greater turbulence. Of the mechanical valves, the tilting disc prosthetic valve causes considerably greater turbulence, in particular in the vicinity of the smaller orifice.

A heart with three arterial trunks (tritruncal heart). Report of a case.

The case is described of a 4 1/2-year-old girl with a previously unreported malformation: a heart with three arterial trunks, aorta, main pulmonary artery, and an intermediate vessel, called "intermediate trunk" because it was situated between the aorta and the main pulmonary artery. Each of these three arteries had a semilunar valve at its origin, and their lumens were completely separated from each other. The pulmonary trunk arose from the right ventricle, while the aorta and the intermediate trunk arose from the left ventricle. The intermediate trunk continued as the right pulmonary artery. The pulmonary trunk continued as the left pulmonary artery. The outflow tracts of both ventricles were normal. There were therefore three arterial trunks arising from a heart with two outflow tracts. Our hypothesis on the embryopathogenesis of this case is that there was double septation of the primitive arterial trunk and the aortic sac, without involvement of the conus. In addition, there was a malalignment between the truncal and conal septa. This entity, however rare, should be considered in the differential diagnosis of absent or anomalous right pulmonary artery.

[Single ventricle. II. Clinical study. Special studies and surgical treatment]. / Ventriculo único II. Estudio clínico. estudios especializados y tratamiento quirúrgico

A study was made of 29 cases of single ventricle confirmed by autopsy, hemodynamic study, or both. It must be emphasized that the term single ventricle excludes whatever malformation which shows traces of an intraventricular septum. Thus conceived, the malformation has been seen to have different clinical courses, which only permit partial diagnosis that may suggest the possibility of "single ventricle". In live patients this can only be diagnosed with specialized studies. In outline, there exist 4 types of clinical hemodynamic behavior: 1) The type with marked increase of pulmonary flow, in which the single cavity vascular systems, pulmonary and aortic, had similar pressures. This type behaves, in a certain way, like large interventricular communications. 2) The type which behaves hemodynamically like a large hypertensive communication with delayed cyanosis of rapid evolution and with few manifestations of heart failure. 3) The third type also has pulmonary hypertension with delayed cyanosis. This differs from the preceeding in that there is a preferential flow in such a way that the venous blood proceeding from the right atrium empties into the aorta and the arterial blood from the left atrium empties into the pulmonary artery. 4) The fourth type is characterized by rapid cyanosis and from the anatomical point of view has stenosis or atresia of the pulmonary artery. An analysis was made of the varieties which within these four classes actually ocurred or cases which were present as theoretical possibilities: single ventricle with crossed great arteries; single ventricle with transposition of the great arteries; single ventricle with partial distortion of the great arteries; single ventricle with common trunc. A detailed analysis was made of the clinical, hemodynamic, electrocardiographic, and radiological manifestations which are seen in these combinations and an anatomic-embriologic classification is proposed on the basis of the systematization of the 29 cases of the present study. Finally brief considerations are made of the operability of those cases of single ventricle according to their anatomic variety.

[Single ventricle. New embryological-anatomical classification. I. Pathology and physiology]. / Ventriculo único. Nueva clasificación embriológico-anatómica I. Patología y fisiología

The different nomenclatures which have been given to this malformation are discussed, defining the single ventrical as a single ventricular chamber without an interventricular septum and generally with two well defined atrioventricular orfices, although in some cases there is only one mitral-tricuspid ring. Twelve cases of single ventricle, proven by necropsic study, were examined. A new embriological-anatomical classification was proposed based on the location of the outflow tract (concordant or discordant in relation to the situs viscerae of which it is a part) and the troncoconal morphology (crossed great vessels, transposition of the great arteries, and truncus arteriosus), presenting some examples of these malformations. The pathological characteristics of the malformation in each of the established groups is described, as well as the physiopathology in the most frequent varieties. The defects associated with single ventricle are studied.

[Primary prevention of rheumatic fever. Occurrence of beta hemolytic Streptococcus of the A group in 11,314 students in Magdalena Contreras]. / Estudios sobre la prevención primaria de fiebre reumática. I. Prevalencia de estreptococo beta hemolítico del grupo A, en 11,314 escolares de la Magdalena Contreras

A study was made in 11,314 school-age children to determine the prevalence of streptococcus pyogenes group A. The children studied belonged to a low socioeconomic group of one of the political boroughs of the Federal District. The prevalence found was 6.86%. There were no differences in the percentage of carriage according to the school surveyed or the school grade studied. However, marked differences were found when the presence of arthralgias was related to the carriage of streptococcus. Children complaining of artharlgias showed twice as much streptococcus in their pharynx than the ones not carrying it.

[Tricuspid atresia: A therapeutic problem]. / Atresia tricúspidea: un problema terapéutico

1. The authors present 80 cases of tricuspid atresia of the Children's Cardiology Service of the Instituto Nacional de Cardiología de México. They propose their own classification based on the position of the visceral suits and of the great arteries and the possible existance of a persistent truncus arteriosus. 2. The requirements that should be fulfiled to establish an anatomic and hemodynamic diagnosis are determined; and the need to know in detail the anatomy of the right ventricle; of its exit chamber, of the pulmonary valve and of the pulmonary truncus is emphasized; as well as the measures in the auricles and the left ventricle. 3. They insist upon the need, when the pulmonar arterial pressure cannot be measured directly, to introduce a catheter in a pulmonar vein, because the pressures obtained are quite similar to the pressure in the pulmonar arterial territory. 4. The fundamental data of the anatomic and hemodynamic study are discussed and illustrated. They confirm the close relation that exists between the diameter of the exit chamber of the right ventricle and of the valvular ring, the pulmonary truncus and its branches. 5. In all cases of tricuspid atresia with AQRS deviated to the right and downwards in the frontal plane; transposition of the great arteries should be thought of when it deviates to the left and upwards, in patients with crossed great arteries. 6. In the cases operated with sistemic-pulmonary fistula, there was an intrahospital mortality range of 25%, similar to that obtained by most authors. 7. The paliative surgical procedures are analyzed, and those that at present could be considered as "corrective" such as Fontan and Kreutzer's operations. The need, to gather several diagnostic parameters. To establish the surgical indication in the sistemicpulmonary and venus shunts, is emphasized.

[Electro-ventorcardiographic manifestations of ventricular inversion with transposition of great arteries]. / Manifestaciones electro-vectocardiográficas de la inversión ventricular con transposición de las grandes arterias

Electrocardiograms obtained in two groups of patients with inversion of the ventricles and transposition of the great arteries, were analyzed: group I corresponding in situs solitus and group II to situs inversus. This series comprises 36 cases (29 of group I and 7 of Group II), in which the diagnosis of the main congenital heart disease --ventricular inversion-- and of the associated defects was established by angiocardiography. In 7 cases of group I and in one of group II, the angiocardiographic diagnosis was proved at least in part during open heart surgery. Direct anatomic study was possible in 5 more cases of group I and in 2 more of group II. Each group comprises two subgroups: A, without RBBB, and B, with RBBB of different degrees. Group I consists of 11 cases of subgroup A and 18 of subgroup B. In group II there were 2 cases of subgroup A and 5 of subgroup B. Vectorcardiograms were obtained following Grishman's method in 17 cases of group I (8 of subgroup A and 9 of subgroup B) and in 3 cases of group II (1 of subgroup A and 2 of subgroup B). In 7 cases of group I (5 of subgroup A and 2 of subgroup B), it was possible to record also the vectorcardiographic curves following Frank's method. Electro and vectorcardiographic findings were correlated with hemodynamic data and, in some cases, also with anatomic ones.

Cardiac and pulmonary diseases. A pathophysiologic interelationship.

Left heart diseases, in particular mitral stenosis, are often associated with anatomic and functional alterations of the lung. According to the pulmonary structures involved they could be named chronic secondary intersticial and vascular lung diseases. Congenital heart diseases with pre- or post-tricuspid shunts are also often associated with anatomic and functional alterations of the lung. This condition also constitutes a chronic secondary vascular lung disease (atrial septal defect) or a chronic primary vascular lung disease ( ventricular septal defect, patent ductus arteriosus). Primary lung diseases (interstitial pulmonary fibrosis, pulmonary emphysema, recurrent pulmonary embolism) are often associated with right ventricular hypertrophy with or without dilation, a condition commonly named chronic cor pulmonale. On the whole the interrelationships between heart and lung diseases are as follows: a) anatomic and functional alterations of the lung due to left heart diseases are mediated through pulmonary venous hypertension; b) anatomic and functional alterations of the lung due to congenital heart diseases are mediated through the increased pulmonary blood flow with or without transmission of the systemic blood pressure to the pulmonary vasculature, and c) anatomic and functional alterations of the right ventricle due to primary or secondary lung diseases are mediated through arterial pulmonary hypertension. In summary, the interrelationships between heart and lung diseases are mainly mediated through the pulmonary venous or pulmonary arterial hypertension.