No variation in Hsp70 mRNA level during cardiac surgery in pediatric patients evaluated by semiquantitative RT-PCR.

We evaluated mRNA expression of the heat shock protein gene, Hsp70-1, by means of a semiquantitative RT-PCR in atrial tissue specimens from pediatric patients collected before and after cardiopulmonary bypass surgery for congenital heart diseases, to see whether surgical stress may affect the expression level of this mRNA. We studied thirty nine pediatric patients (aged 3 months to 15 years) undergoing surgical correction of congenital heart malformation. Twenty-one patients were affected by the tetralogy of Fallot, two by combined atrioventricular septal defects, six by ventricular septal defect, three by atrial septal defect, two by atrioventricular canal defect, two by pulmonary valve stenosis, one by mitral insufficiency, and one by double-outlet right ventricle. Our results showed no significant changes in the Hsp70-1 mRNA expression in atrial tissue of patients before and after cross-clamping (the mean relative expression after cross-clamping was 1.0+/-0.6 compared to the baseline value). Furthermore, no significant correlations were observed between cross-clamping time and temperature, cardiopulmonary bypass time and mRNA variation. Our study suggests that, during cardioplegia, myocardial tissue does not have an appropriate adaptive response to surgical stress.

Surgical closure of muscular ventricular septal defects using double umbrella devices (intraoperative VSD device closure).

OBJECTIVES: Surgical closure of some muscular ventricular septal defects has been proven to be difficult. In order to simplify the surgical technique we have used intraoperatively Rashkind double umbrella devices to occlude muscular ventricular septal defects. METHODS: On the basis of haemodynamic and echocardiographic study five children aged 4, 6, 7, 14 and 41 months were considered suitable candidates for intraoperative closure of muscular ventricular septal defects (midmuscular in three cases, apical in two) by Rashkind devices. Three of them had previously undergone pulmonary artery banding at 10, 11 and 41 days, respectively. During hypothermic cardiopulmonary by pass a delivery system was introduced across the tricuspid valve into the right ventricle and then passed through the ventricular septal defect; the distal umbrella of a 17 mm device was opened in the left ventricular cavity; a traction was applied to the introducer and the proximal umbrella was opened on the right side straddling the interventricular septum; the device was then secured on the right side by few stitches. In one case because of the wide diameter of the ventricular septal defect two umbrellas were used. The surgical procedure was completed with debanding and/or closure of other defects close to the aortic or tricuspid valve. RESULTS: Immediate results, tested by epicardial or transesofageal echo, showed a minimal residual shunt in 4 patients and a moderate shunt in one. No early deaths occurred. A complete atrioventricular block developed in 1 patient who had an additional perimembranous defect closed with a prosthetic patch: a permanent pace maker was inserted 3 months after the operation. There was a late death for untractable right ventricular failure in 1 patient who had a large residual shunt erroneously considered moderate. In this patient, the size of the defect was underestimated both preoperatively then intraoperatively. The four survivors are doing well with no signs of hemodynamically significant residual shunts. CONCLUSIONS: The use of Rashkind umbrella devices for closing intraoperatively muscular defects can be helpful to standard surgical techniques when technical problems make patch closure difficult. Its use avoid the need of left ventriculotomy. Careful definition of the size of the defect is mandatory to select suitable candidates.

[Truncus arteriosus with an unusual anatomy of the pulmonary arteries: a report of a surgically treated case]. / Truncus arteriosus con inusuale anatomia delle arterie polmonari: descrizione di un caso trattato chirurgicamente.

The authors describe the rare case of an infant, 35 days old at operation, with truncus arteriosus in which the right pulmonary artery rose from the left posterolateral side of the truncus arteriosus above the truncal valve, and the left pulmonary artery from the inferior aspect of the proximal third of the aortic arch. At operation, the right ventricle-pulmonary artery continuity was reconstructed with an aortic homograft. The left pulmonary artery was anastomosed "end-to-side" to the left carotid artery of the aortic homograft, and the right pulmonary artery "end-to-side" to the joined openings of the left subclavian artery and descending thoracic aorta. It was difficult to understand if the first tract of the left pulmonary artery (2 mm in diameter) was a true pulmonary artery, a ductus arteriosus or an anomalous vessel. The infant survived the operation. Intensive postoperative treatment was necessary to counteract severe episodes of pulmonary hypertension. Enoximone 5 mcg/Kg/min and prostacyclin 5-10 mcg/Kg/min were effective in reducing pulmonary vascular reactivity. Four month follow-up shows optimal surgical correction and normal hemodynamic findings.

Hypertrophic obstructive cardiomyopathy. Late follow-up after ventricular myotomy-myectomy.

A series of 25 patients with hypertrophic obstructive cardiomyopathy, isolated or associated with minor anomalies, were operated upon using a modified Morrow's procedure. The indication for operation was based on either the presence of severe symptoms despite treatment with beta-blocking agents, or a significant peak gradient of over 50 mmHg even in asymptomatic patients. All patients survived and none was lost to follow-up. Long-term results were evaluated with 2-dimensional echocardiography. Surgical versus pharmacological treatment is discussed, with particular consideration given to paediatric patients.

Quadricuspid aortic valve.

A case of quadricuspid aortic valve is described. The anomaly was unexpectedly found during operation for aortic valve replacement in a 70-year-old woman. Macroscopic and histological examinations of the valve showed no sign of previous inflammatory disease. Quadricuspid aortic valve must be considered, therefore, a malformation capable of leading to severe valve failure in later life.

Chylothorax following cardiac surgery in children.

Eleven cases of chylothorax following cardiac surgery in children are described. Conservative treatment was carried out with success in all patients but one, who died because of the underlying cardiac pathology, with the chylothorax still present. Our results indicate that conservative treatment is effective in children, although surgery has been previously considered by some authors as the treatment of choice in this age group.

The syndrome of congenital absence of the pulmonary valve: pathological, clinical and surgical considerations.

Four cases of congenital absence of the pulmonary valve are described. Three of them underwent successful operation. The fourth case, operated on in the first days of life, died because of severe respiratory distress. After examining the embryological aspects of this malformation, its treatment is discussed in relation to particular respiratory problems in infants and to the possibility of inserting prosthetic valves in children undergoing elective surgical treatment.

Ventricular septal defect associated with aortic regurgitation. Surgical considerations.

Fifteen consecutive cases of ventricular septal defect (VSD) associated with aortic regurgitation (AR), observed from January 1972 to November 1980 in the Department of Cardiac Surgery of Massa Hospital were evaluated from a pathological and hemodynamic point of view and surgically treated. All patients underwent cardiac catheterization and selective aortography before and after surgical correction. The VSD was closed by Dacron patch in 10 cases and by direct suture in 5. Aortotomy was performed in 9 patients who presented moderate to severe AR; among these 7 underwent valvular repair and two prosthetic replacement. One patient died (6.6% mortality) 8 days after the operation; another developed complete atrioventricular block requiring insertion of epicardial pace-maker. Residual AR has been found in only one of the 6 patients with preoperative mild degree of AR in whom only the closure of the VSD was carried out. Residual AR is also present in 4 patients who required valvular repair, but only in one it is severe. We favor correction at preschool age on the principle that early closure of the VSD may control or prevent the progression of AR. However, in small children in whom the severity of AR may suggest the necessity of valve replacement, the operation is postponed as long as possible to avoid functional prosthetic stenosis later in life.