Experimental evaluation of atriopulmonary anastomosis in the presence of high pulmonary resistance.

We studied pulmonary resistance as a surgical criterion for atriopulmonary shunt. We created a model of experimental pulmonary hypertension by establishing a systemic-pulmonary shunt in 11 dogs. Two to 3 months after the shunt operation, total pulmonary resistance was calculated before (7.24 +/- 1.54 U . m2) and after (3.50 +/- 1.54 U . m2) ligation of the shunt. An atriopulmonary anastomosis technique was then performed and the hemodynamic status of the dogs during the first 2 postoperative hours was evaluated. Pathologic study of the lungs disclosed no arterial lesions. From our experimental work, we conclude that the surgical criterion for establishing the indication for this operation should be pulmonary resistance, which is conditioned by the state of the intrapulmonary vessels. We propose a procedure for determining real pulmonary resistance in the course of preoperative catheterization.

Does a critical hemodynamic situation develop from right ventriculotomy and free wall infarct or from small changes in dysfunctional right ventricle afterload?

An experimental model for right ventricle free wall infarct associated with double ventriculotomy and tricuspid insufficiency was created to evaluate whether right ventricle failure can cause profound refractory heart failure or whether modifications in right ventricular afterload are more influential in this regard. In our model, the left ventricle, interventricular septum and right atrial wall were maintained intact and pulmonary banding made it possible to modify right ventricular afterload during the experiment. The results of our study showed that pure right ventricular failure does affect the hemodynamic state negatively, but it is not itself, a cause of death in dogs. A slight increase in the dysfunctional right ventricular afterload produced a profound deterioration in the hemodynamic state that required pulmonary artery debanding within no more than 10 minutes.

[Left subclavian-pulmonary trunk fistula with a vascular prosthesis as palliative treatment in Fallot conditions]. / Fístula subclavia izquierda-tronco pulmonar con prótesis vascular como tratamiento paliativo de las situaciones de Fallot.

In this paper, our experience with a new systemic-to-pulmonary artery shunt: subclavian-pulmonary artery trunk shunt with PTFE (central shunt) is presented. Between November 1985 and March 1990 this central shunt was employed in 8 children with ages ranged between 4 days and 3 years, and weights between 2 and 12 kg. Diagnosis were Fallot's tetralogy in three; pulmonary atresia with intact septum in three; complete AV canal and Fallot's tetralogy in one, and univentricular heart and pulmonary atresia in 1 patient. There were no surgical deaths. Hospital mortality was present in 1 case (AV canal and Fallots tetralogy) at the moment of reoperation 1 month later. Follow-up ranged between 2 and 46 months. One case, pulmonary atresia with intact septum, has undergone total correction. The remainder 6 cases are in good situation with O2 saturation above 70%. This central shunt has the advantages to provide a bidirectional blood flow to both pulmonary branches avoiding the risk of direct damage in the pulmonary arteries found with the conventional aorto-pulmonary shunts.

[Vascular rings of aortic origin: the surgical experience in 43 cases]. / Anillos vasculares de origen aórtico: experiencia quirúrgica en 43 casos.

INTRODUCTION AND OBJECTIVES: Aortic vascular rings can produce compression and obstruction in the airway and/or esophagus early surgical treatment in the first days or months of life. The reported incidence range between 0.3-0.6% with an 0.5% in our series. The following is a retrospective analysis with clinical, radiological and angiocardiographic study of the patients operated on in our service with the diagnosis of aortic vascular ring focused on the surgical results. METHODS: A total of 43 children with ages ranging between 21 days and 10 years (mean age 17 months) underwent surgical treatment for aortic vascular ring, during the period between january 68 and january 94. Clinically, 74% had stridor, 27.4% gastroesophageal reflux, 34% pulmonary infection, 14% respiratory insufficiency with mechanical ventilation, 12% heart failure, 9% dysphagia, 2% crisis of bronchospasm and 2% tracheomalacia that require tracheotomy prior to surgical correction. Diagnosis was made by esophagogram 86% of the cases. Aortography as the late diagnosis method or for election to surgical approach was made in 85% of the cases. In 42% were double aortic arch, 32% anomalous right subclavian artery and 25% right aortic arch with left ductal ligamentum. RESULTS: Reoperation was performed in 4 cases. Two early (1 case for hemorrhage, 1 case for phrenic paralysis requiring diaphragmatic plication), and two late reoperations (1 aortopexy, 1 tracheal termino-terminal anastomosis) at 2 and 13 months respectively. Hospital mortality was 1 case (2%) with 1 additional late death (2%). Follow-up was performed in the remaining 39 cases with a mean of 11 years (ranging between 1 and 25 years. Thirty seven of 41 patients alive asymptomatic (90%). CONCLUSIONS: Due to a low mortality rate (2.3%) not related with the age of the patient at the moment of the surgical procedure based in our experience, we conclude that it is very important to perform both, early diagnosis and surgical treatment in order to avoid the potential residual lesion on the airway caused by tracheo-broncho malacia, in order to avoid the deleterious effect on the results both at early and later follow-up.

[Technical innovations in total extracardiac cavo-pulmonary connection in Fontan-type operation. An experimental study and first 2 operated clinical cases with excellent immediate results]. / Innovaciones técnicas de la conexión cavo-pulmonar total extracardíaca en la cirugía tipo Fontan. Estudio experimental y dos primeros casos clínicos operados con excelentes resultados inmediatos.

INTRODUCTION: Three technical modalities are presented with total extracardiac cava-pulmonary connection, with bidirectional Glenn, as coverage of this type of extracardiac connection for all types of cardiopathies suitable for Fontan type correction. METHODS: Development of an experimental protocol for the perfecting of the three technical variants tested: "Tunnel from inferior cava to right pulmonary artery by means of right atrial wall and vascularized pericardium", "Tunnel from inferior cava to the trunk of the pulmonary artery with or without pulmonary valve with P.T.F.E. hemiconduit" and "Tunnel from inferior cava to the pulmonary graft as a artery with P.T.F.E. graft as a hemiconduit". RESULTS: The first two clinical cases operated on using the third technical variant are presented. Both cases evolved during immediate postoperative period with a very favourable hemodynamic response, with pressures at conduit and P.A. level of 10-12 mmHg, normal cardiac output and sinus rhythm. The later clinical evolution in both cases is very satisfactory. The five cases published by Laschinger with this same technique showed a very favourable evolution during the immediate postoperative period and later. CONCLUSION: The technical facility of its performance, the slight traumatism of this surgery, the important technical advantages with respect to the total cava-pulmonary intraauricular connection and the good initial hemodynamic results make us consider the total extracardiac cava-pulmonary connection as an important contribution in this type of surgery. It is clear that time and greater clinical experience with this type of connection is required for the correct evaluation of all and each one of the numerous theoretical advantages shown and in order to detect possible disadvantages.

[Experimental evaluation of the role of the coronary sinus pressure in the regulation of coronary return volume via the coronary sinus. Surgical considerations in atrio-pulmonary diversion procedures]. / Valoración experimental del papel de la presión en seno coronario en la regulación del volumen de retorno vía seno coronario. Consideraciones quirúrgicas en las técnicas de derivación atriopulmonar.

In order to find out the validity of the vascular waterfall mechanism in coronary venous circulation, the role of coronary sinus pressure in the regulation of coronary return volume via the coronary sinus is studied in healthy animals. An experimental model of pressure regulation in the coronary sinus was prepared, and aortic pressure, EKG and the cardiac output (measured by thermodilution) were recorded. The return volume via the coronary sinus was measured at coronary sinus pressure of 10 or less, 15, 20, and 25 mmHg or more, for a total of 36 determinations. Increased coronary sinus pressure did not produce significant changes in aortic pressure, heart rate, cardiac index or coronary return volume via coronary sinus. When coronary sinus pressure was 25 mmHg or more, there was a significant decline in the average of coronary return volume via coronary sinus. Nevertheless, stepwise variant regression showed that the coronary sinus pressure per se does not condition the volume of coronary return via the coronary sinus. Our results suggest that in the healthy animals, the vascular waterfall mechanism in coronary venous circulation is not valid. Our results suggest that in the correction of congenital cardiac malformations using atriopulmonary anastomosis procedures, employing techniques that ensure coronary sinus drainage into the left atrium, in order to avoid the hemodynamic repercussions attributable to the vascular waterfall mechanism, is not justified.

[The treatment of the tracheobronchial stenosis by extracorporeal circulation]. / Tratamiento de las estenosis traqueo-bronquiales mediante circulación extracorpórea.

Six children with tracheobronchial stenosis secondary to cardiovascular ring were operated with extracorporeal surgery. Three of them with pulmonary sling had a tracheobroncoplasty with costal cartilage, one with xiphoides appendix and another with pericardio. One girl 2 years old was operated resecting three tracheal rings and anastomosis end to end. The child that was operated with pericardio died with infection and sepsis three months after the operation. The other five are well five, four and two years after plasty.

[Vascular rings]. / Anillos vasculares.

30 patients with vascular rings operated between 1966 and 1985 are described. Age, sex and symptomatology are studied. Nineteen had a double aortic arch, 9 cases had anomalous subclavian artery, 6 patients had right aortic arch with ductus or ligamentum arteriosum, 1 patient had pulmonary artery sling and 1 patient had right aortic arch and ductus arteriosus and anomalous subclavian artery. Associated congenital malformations were seen in 8 (27%) patients. Basic surgical procedures include a left thoracotomy, identification of the aortic arch anatomy and division of anomalous ring. The aortic arch malformations have a good prognosis with early diagnosis ans surgical treatment.

[Congenital heart defects with tracheal and bronchial stenoses: surgical treatment with extracorporeal circulation]. / Cardiopatías congénitas con estenosis traqueales y bronquiales: tratamiento quirúrgico con circulación extracorpórea.

We present our experience with the surgical management of congenital cardiac defects when tracheal or bronchial stenosis is present. Concerning pulmonary artery sling, we think that it is necessary to correct the cardiac malformation and trachea-bronchial stenosis at the same time. After surgical correction, if the patient cannot be weaned from mechanical ventilation (10-15 days), it is mandatory to rule out the presence of tracheo-bronchial tree lesions in order to perform surgery without delay. The operation should be performed under cardiopulmonary by-pass at the same time as the surgical correction of the cardiac malformation. We believe that the best technique for localized obstruction is resection of the stenotic area, followed by termino-terminal anastomosis (one case in our patient group). However, when the length of the obstruction is longer, our election is to enlarge the stenotic area with pre-molded cartilage (four cases).

[Surgical treatment of congenital cardiopathies in the 1st year of life: experience in 893 treated cases]. / Tratamiento quirúrgico de las cardiopatías congénitas en el primer año de la vida: experiencia en 893 casos intervenidos.

We present a study of 893 infants treated surgically, of ages from 30 hours to 12 months old, with a global mortality rate of 23.1%. In 37.6% of the cases, a total correction of cardiopathy was reached, using closed techniques in 25.9% and open-heart surgery in 11.7%. Palliative techniques wer chosen in 62.3% of the patients. The highest mortality corresponds to those patients under one month old (40%), decreasing to 14% in the 7-12 month old group. Surgical indications and techniques used are commented in each group of cardiopathies, making special reference to post surgical care.

[Tetralogy of Fallot: total repair in the first year of life]. / Tetralogía de Fallot: corrección total en el primer año de vida.

OBJECTIVE: Since the first correction of tetralogy of Fallot in 1955, the optimal age for total correction has been in continuous debate and remains a controversy. PATIENTS AND METHODS: Here we present our experience with 44 patients with tetralogy of Fallot which was surgically corrected in the first year of life. In 37 cases total correction was achieved with the first operation. In the remaining 7 cases previous palliative surgery was performed. Details of surgical decision making, hemodynamic data and surgical procedure are described in detail. RESULTS: There were 8 deaths (18.1% mortality rate). There were no deaths in the last 24 consecutive cases. Complications, need for reoperation and long-term follow-up of the 36 survivors are discussed. CONCLUSIONS: After a detailed analysis of both results and follow-up, our surgical criteria is described, with the intention of performing palliative surgery in only a restricted number of cases of tetralogy of Fallot where the anatomy is unfavorable for total correction with a single intervention.

A new physiologic correction technique for re-establishment of pulmonary circulation. Experimental surgical development.

A new physiologic technique is presented for surgical correction of truncus arteriosus, pseudotruncus, transposition of the great arteries, double right ventricular outflow tract with subpulmonary ventricular septal defect and certain cases of Fallot's tetralogy. The basis of the technique are creation of a neo-right atrium, neo-pulmonary trunk, neo-right atrioventricular valve and a neo-pulmonary valve by right angular atriotomy and insertion of a homologous pericardial patch with a monocuspid valve. The pulmonary circulation is re-established by anastomosis of the neo-pulmonary trunk to the pulmonary tree. The technique was used on 26 mongrel dogs. In 14 the experiments were preliminary, to evaluate the technique's validity, and in the other 12 it was performed with extracorporeal circulation and the hemodynamic status was studied at 30 and 180 min postoperatively. The technique and its results and potential advantages are described. Clinical application is considered to be feasible.