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D Zavaleta

Publications and source records attributed to D Zavaleta.

14 recordsLinked to original sources

Congenital absence of pulmonary valve leaflets.

Congenital absence of pulmonary valve leaflets is an uncommon condition usually associated with ventricular septal defect and an obstructive pulmonary valve ring. Twenty-one patients with these malformations are described. Twenty had an associated ventricular septal defect with ventriculoarterial concordance, and one also had transposition of the great arteries, ventricular septal defect, and obstructive pulmonary valve ring. The clinical features, cardiac catheterisation findings, and angiocardiographic results are presented. Twelve patients underwent cardiac surgery. Three patients died, one in the early, and the other two in the late postoperative period. The results, according to the surgical technique employed and postoperative cardiac catheterisation findings, showed that patients in whom the bioprostheses were implanted in the pulmonary position had a better late follow-up.

Adolescent↗

[Juxtaposition of the atria].

Left juxtaposition of atrial appendages is an anomaly of their origin and position which is associated with a high incidence of complex congenital heart defects. We studied six cases of juxtaposed right atrial appendages. They emerged from the anterior wall adjacent to the atrial septum and were situated to the left of the origin of the great arteries. Associated congenital heart defects were: single outlet, right ventricular hypoplasia, absent right atrioventricular connection, ventricular and atrial septal defects and pulmonary outflow obstruction. Other abnormal morphological features present were anatomically corrected malposition of the great arteries, bilateral infundibulum and right aortic arch. Although the association of these malformations with juxtaposed atrial appendages does not per se constitute a syndrome, its presence is an ominous sign of severe cyanotic congenital heart disease which should alert both clinicians and surgeons. There are various possible embryological explanations for the genesis of this malformation. We believe that juxtaposition is the consequence of the ectopic origin of the atrial appendage rudiment, which in the presence of truncal alterations grows behind and to the left of the great arteries.

Heart Atria↗

[Malposition of the great arteries. Is this term a valid one?].

We present four cases of a congenital heart malformation classically known as malposition of the great arteries. This term means there are concordant ventriculo-arterial connections with abnormal spatial relations of the aortic and the pulmonary arteries, in which the former is anterior relative to the latter, and either to the right or to the left, according to the position of the corresponding ventricle. This anomaly can be found in any type of atrial situs, notwithstanding the type or mode of atrioventricular connection, as in the cases we studied. If we consider that this anomaly depends on the associated lesions in order to produce physiological heart alterations, we think that the term of malposition of the great arteries is not valid, since in the anatomic diagnosis of congenital heart disease it is important to consider the connections between atria, ventricles and arteries, the spatial relations between them being of second importance.

Adolescent↗

[Double inlet left ventricle].

Twenty-five cases of double-inlet left ventricle, 23 in atrial situs solitus and 2 with dextroisomerism are described. Twenty had both atrioventricular valves and in 3 a common atrioventricular valve connected to the left ventricle. In rest, the left atrioventricular valve was straddling over the left-sided right ventricle in about 15%. The position of the rudimentary right ventricle varied from superior, anterior and to the right of left ventricle (6 with transposition and 9 with concordant ventriculo arterial connection), to superior anterior and to the left of left ventricle (10 cases, all with transposition). Five cases had stenosis of the left atrioventricular valve and 2 stenosis of the right one. In 11, the clinical presentation was dominated by cyanosis, reduced pulmonary blood flow and right to left shunt. The rest had cyanosis and congestive heart failure. Five patients with right ventricle on the left had complete atrioventricular block, 9 right AQRS orientation and all of them findings of left ventricle hypertrophy. Three cases showed initial Q wave in VI and one left bundle branch block. Cases with right ventricle on the right, had left QRS orientation, left ventricle hypertrophy and 2 complete atrioventricular block. Cross-sectional echoes showed in 13, two atrioventricular valves committed to the left ventricle; in 3 of them the right ventricle was visualized. In 22 cases angiography determined the type of atrioventricular connection. Double inlet left ventricle is one of the most challenging diagnosis in congenital heart disease. Considering its lack of clinical specificity and according to our results, the electrocardiogram, echocardiogram and angiographic findings are of great help for its identification.

Adolescent↗

[Ebstein's anomaly in infants].

Ebstein's disease is a congenital malformation of the tricuspid valve that causes various hemodynamic alterations depending on the anatomic changes in the valve, presence or absence of atrial septal defect and reduction in the ventricular function. We present 19 patients with Ebstein's malformation of the tricuspid valve younger than 2 years of age. The long-term follow-up was from 1 week to 16 years with a mean of 40 months. Eight children died, 6 were lost in the follow-up and 5 survived. Early cyanosis with associated lesions give a bad prognosis. If the child survives the first year of life he has a better long term prognosis.

Arrhythmias, Cardiac↗

[Double outlet right ventricle with discordant atrioventricular connection. Clinical study].

The clinical and anatomic findings were reviewed in 17 patients with double-outlet right ventricle and atrioventricular discordance. Ten cases had atrial situs solitus, seven with right-sided heart three with left-sided heart. Seven cases had atrial situs inversus, five with left-sided heart and two with right-sided heart. All cases presented ventricular septal defect, 13 subvalvar pulmonary stenosis, two tricuspid regurgitation and two complete atrioventricular block. The spatial relationship between the arterial valves are variable. Most cases in atrial situs solitus had a left-sided and anterior aorta and all patients in atrial situs inversus had a right-sided and anterior aorta. In this study we compared the anomalies found in our cases with double outlet right ventricle with those in 58 patients with corrected transposition. Absolute, relative and attributable risks were calculated for the presence of subvalvular pulmonary stenosis, ventricular septal defect, tricuspid regurgitation and atrioventricular block for each the two groups. We concluded that patients with double-outlet right ventricle are more prone to present ventricular septal defect and subvalvar pulmonary stenosis, while those with corrected transposition have a greater likelihood of presenting with tricuspid regurgitation and atrioventricular block. There is no typical clinical picture for the malformations. Symptoms depend upon the associated anomalies. The final diagnosis is best achieved by the echocardiographic and angiocardiographic studies, but electrocardiogram and chest radiograph may suggest the presence of a discordant atrioventricular connection.

Adolescent↗

[Tetralogy of Fallot associated with supravalvular mitral membrane].

Two children with tetralogy of Fallot and supravalvular mitral membrane are reported. In both, the diagnosis was established before surgery. In the first case, clinical data suggested the associated mitral lesion and a two-dimensional echocardiogram demonstrated a supravalvular membrane. In the second patient, mitral obstruction was diagnosed by Doppler echocardiography and the supravalvular membrane was visualized by means of the angiographic study. Despite the rare association of both malformation, the importance of its clinical recognition is mainly related to the surgical correction of both lesions.

Child, Preschool↗

[Electrocardiographic findings in pulmonary arterial hypertension in children].

Pulmonary hypertension (PH) induces high risk of cardiovascular morbidity and mortality, mainly in the primary or essential type. Invasive studies are needed to confirm the diagnosis; among the non- invasive approach, the electrocardiogram has been used to suspect such entity with poor results due to inadequate diagnostic criteria. Twelve children with pulmonary hypertension of the essential type (PPH) and ten children with PH due to interventricular septal defect (VSD) were studied haemodynamically and electrocardiographically and compared to electrocardiographic data of 53 normal children. PPH showed higher resistances than VSD (17.2 +/- 1.9 vs 6 +/- 0.6 u/m2 p less than 0.01) with the same pressure level (99.5 +/- 10.3 vs 101.5 +/- 4.8 mmHg). Right axis deviation, peaked P wave, increased ventricular activation time and prominent ST-T changes were seen in PPH patients whereas in VSD the electrical axis was within normal limits, without P wave changes and in some cases, less conspicuous ST-T abnormalities were observed (p less than 0.01). Such changes showed good sensitivity (80%) and specificity (81%) to suspect PH with resistances higher than 10 u/m2 with a predictive value of 75% (p less than 0.02). P wave and ST-T changes could be of use to suspect PPH with elevated resistances instead of right ventricular hypertrophy voltage criteria.

Child↗

[Fibrous fixed subaortic stenosis].

Fifty eight patients with isolated with discrete subaortic stenosis or in association with just another heart defect, were studied between 1961 and 1980. The age range was between 2 and 42 years. The evaluation of each case was done according to clinical manifestations, systolic overloading of the left ventricle and the amount of the systolic gradient. There is a poor correlation between the clinical, electrocardiographic and hemodynamic parameters according to the student t test in the preoperative evaluation. Forty-one patients were operated, two of them died in the early post-operative period. There was a good clinical evolution with significant values comparing pre and post-operative symptoms. The decrease in the systolic gradient in 26 cases after surgery was significative (p less than or equal to 0.005). Based on the natural history of this malformation and on the results obtained with the surgical treatment, we may conclude that there is surgical indication once the diagnosis is made, because this malformation has a completely different evolution compared with other forms of congenital aortic stenosis.

Adolescent↗