Ventricular exclusion during Fontan operation: an evolving technique.

The modified Fontan operation, which consists of ventricular exclusion by obliteration of the right atrioventricular ostium, requires a technique that provides firm and permanent occlusion while preserving the atrioventricular node and bundle. Ten patients underwent such an operation. In 5 of them, closure of the right atrioventricular ostium was achieved by suturing a patch into the valve leaflets; in the other 5, the ventricle was excluded by a patch sutured into the right atrial wall above the annulus fibrosus. None of the patients who underwent this procedure experienced heart block postoperatively. However, three instances of late patch dehiscence occurred, each in the group of patients in whom the patch had been attached to the valve leaflets. We conclude that both patching techniques are safe as far as the atrioventricular node and bundle are concerned but that permanent occlusion is better obtained by implanting the patch into the atrial wall. Therefore, we prefer to use this technique.

Right and left isomerism: the cardiac surgeon's view.

We have treated by palliative or corrective surgery 12 patients with the complex cardiovascular anomalies associated with right isomerism (asplenia syndrome) or left isomerism (polysplenia syndrome). A systemic-pulmonary artery shunt was performed in 4 patients, with 2 early deaths. Anatomical intracardiac repair was successfully done in 2 patients, while an orthoterminal repair using a modified Fontan procedure was attempted in 5 patients, only 1 of whom survived. A 1-year-old girl with diffuse pulmonary arteriovenous fistulas associated with left isomerism was not considered a good candidate for operation after an exploratory sternotomy. The surgical options and technical problems related to the complex intracardiac morphology of these developmental syndromes are presented.

Univentricular heart: can we alter the natural history?

Surgical treatment must be considered for patients with univentricular heart in view of their poor natural history. Since one of the major factors influencing the natural history of this malformation is the amount of pulmonary blood flow, we discuss the potential surgical options by separately considering the two main pathophysiological situations: univentricular heart with restricted pulmonary blood flow, and univentricular heart with unrestricted pulmonary blood flow. We have reviewed the early and late results of surgical treatment based on our experience with 19 patients and the data from the literature. Temporary relief of symptoms can be provided by palliative operations (systemic-pulmonary shunt, atrioseptectomy, enlargement of the outlet foramen, pulmonary artery banding, or palliative Mustard or Senning procedure). "Corrective" surgery, by means of either a modified Fontan operation or ventricular septation, carries a high early mortality (about 30%) and a high early and late morbidity, with only 50% of survivors enjoying an asymptomatic life. Studies of the long-term efficacy of palliative operations as well as our experience and that of others with "corrective" operations, which have a relatively short follow-up, do not yet indicate whether presently available surgical procedures can alter the natural history of patients with univentricular heart.

Simplified thoracic approach to the ascending and descending aorta in complex coarctation.

Two patients with left ventricular and proximal aortic hypertension secondary to diffuse hypoplasia of the aortic arch have recently been treated by a surgical technique based on: I simultaneous exposure of the ascending and descending thoracic aorta through a left antero-latero-posterior thoracotomy; 2 insertion of a Dacron graft between the aortic root and the descending thoracic aorta. In both cases equal systemic pressures in the ascending and descending thoracic aorta and adequate distal perfusion were obtained.

Results of aortic valve replacement with the Starr-Edwards and Björk-Shiley prostheses.

A study has been made of the last 50 patients subjected to aortic valve replacement with a Starr-Edwards or a Björk-Shiley prosthesis. The surgical mortality was 6%, the late mortality was 4%. Postoperatively the vast majority of the patients were symptom-free. Paravalvular leakage was believed to be present in two patients, both of them free from symptoms.