Results of 546 Blalock-Taussig shunts performed in 478 patients.

Between 1983 and 1995, 546 Blalock-Taussig shunt procedures were performed in 472 patients: 128 (23.0%) were classical shunts, 90 of them on the same side as to the aortic arch, and 418 (77.0%) were modified shunts, 182 on the same side of the arch. At the time of surgery, 78 patients were aged below one week, 270 from one week to 12 months, and 198 patients were over one year of age. The mean pre-operative arterial saturation (71.7% +/- 16.5%) was significantly increased to 83% +/- 17.9% immediately after the procedure (p=0.017). The overall hospital mortality rate was 2.9% (16/546), with rates of 2.3% (3/128) for the classical, and 3.1% (13/418) for the modified shunts (p=not significant). The rate was significantly higher, however, for classical shunts when the pulmonary arterial diameter was less than 4 mm (15.4% versus zero; p=0.047), though this relationship was reversed for modified shunts (zero versus 3.6%; p=0.338). Early mortality was significantly influenced by the age at surgery, 5/78 (6.4%) in patients aged below 1 week, 3.7% between 1 week and 1 year, and 0.5% over 1 year (p=0.019). Early mortality was also significantly increased in patients weighing 3kg or less, 8/156 (5.1%), versus 3/303 (1.0%), p=0.037. Overall, 51 shunts failed (9.3%), 10 early and 41 late. Early failure was significantly increased in patients weighing 3kg or less, 8/156 (5.1%) versus 3/303 (1.0%), p=0.016. The overall early failure rate was 1.4% (3/215) when heparin was administered intra-operatively and for 48 hours postoperatively, in contrast to an early failure rate of 3.4% (7/203) when heparin was not used (p=0.294). Overall rates of failure during follow-up were 9.1% (17/188) in heparinized patients versus 13.6% (24/177), (p=0.173) in non-heparinized patients. Failure of classical shunts was 10.2% (13/128), compared with 6.7% (28/418) for modified shunts (p=0.195). Failure was more common overall if the pulmonary arterial diameter was less than 4 mm, 14.7% (9/61), as opposed to 8.7% (26/300) when the diameter was 4 mm or greater, (p=0.144). Administration of aspirin during follow-up after the modified shunt procedure reduced failure from 11% (18/163) to 6.7% (10/150), p=0.176. Classical or modified Blalock-Taussig shunts, either on the same side or opposite to the aortic arch, can be performed on patients of any age with minimum postoperative complications and low operative mortality. The use of intra- and post-operative heparin appears to reduce the overall rate of failure, and the administration of aspirin during follow-up appears to reduce failure of modified Blalock-Taussig shunts.

Balloon dilatation of complete obstruction of the superior vena cava after Mustard operation for transposition of great arteries.

Balloon dilatation was successfully performed in two patients with complete obstruction of the superior vena cava baffle junction after a Mustard operation for transposition of the great arteries. Evidence for complete relief of obstruction in the first patient, aged 4 years, was obtained by angiography, which showed improved calibre at the site of obstruction and improved haemodynamic pressure measurement after the balloon dilatation. In the second patient, aged 14 years, the relief was incomplete; in this patient a 3 cm long 3 mm diameter Palmaz stent was successfully implanted.

Experience with 205 procedures of transcatheter closure of ductus arteriosus in 182 patients, with special reference to residual shunts and long-term follow-up.

Between December 1987 and September 1991, 205 nonsurgical procedures for closure of patent ductus arteriosus were attempted in 182 infants, children, and young adults with use of the Rashkind double-disc ductal occluding device. The patients' ages ranged from 8 months to 26 years (median 5 years) with 18 aged less than 2 years. Their weights ranged from 7.4 to 55 kg (median 16 kg); in patients aged less than 2 years the mean weight was 10.2 +/- 1.5 kg, and in those aged more than 2 years mean weight was 19.5 +/- 9.6 kg. Successful occluder device implantation was achieved in 174 patients (96%) at the initial attempt. Device embolization to a pulmonary artery occurred in six patients; two of these devices were retrieved by grabber catheter and four at operation, all without adverse sequelae; there were two other technical failures. Follow-up studies included two-dimensional Doppler echocardiography with color flow mapping. The 6-week follow-up study revealed a small residual shunt in 27% (46/169) of patients. At the 6-month follow-up study, 22% (37/167) of the patients had a small residual shunt; this prevalence was 17% (24/145) in ducts with a narrowest diameter of less than 6 mm, and 59% (13/22) in ducts greater than 6 mm. Immediately after implantation of the occluder device and throughout the follow-up period, the mean narrowest ductal diameter of ducts with residual shunts was significantly larger than that of ducts in which total occlusion was achieved (range of p < 0.01 to 0.001). The use of the 17 mm occluder device, however, was significantly associated with an increased prevalence of residual shunt only immediately after implantation (p < 0.01). Implantation of a second occluder device was attempted in 21 patients with residual patent ductus together with a continuous murmur at the 6-month follow-up; embolization of one device to a pulmonary artery occurred immediately but it was retrieved by grabber catheter and another device was successfully implanted 1 month later. All 21 patients were seen for 6-month follow-up study, when only one (5%) had a small residual shunt that was subsequently successfully closed by the insertion of a third occluder device. Thus, after successful implantation of one or more occluder devices, complete closure of the ductus was achieved in 90% of all patients seen to date for their 6-month follow-up study. One patient had limited hemolysis. The maximum follow-up period is 50 months. These results confirm the efficacy, with low morbidity and no mortality, of the use of the Rashkind occluder device for nonsurgical closure of patent ductus arteriosus, especially in those with smaller diameters.

Blade atrial septostomy: experience with the first 50 procedures.

We have performed 50 blade and balloon atrial septostomies in 46 patients with diagnoses of transposition of the great arteries--32 patients; mitral atresia or stenosis--10 patients; total anomalous pulmonary venous drainage--2 patients; tricuspid atresia--1 patient; and pulmonary valve atresia with hypoplastic right ventricle--1 patient. The patients' age ranged from 1 day to 72 months (median = 8 months) and weights ranged from 2.7 to 14.5 kg. In patients with transposition the systemic saturation increased from an average of 62% to 74.6% (p less than 0.001) and the inter-atrial mean pressure gradient was reduced from 7.74 +/- 5.3 to 1.4 +/- 2.04 mm Hg. Patients with mitral atresia had no significant increase in systemic arterial saturation but a significant decrease in the mean inter-atrial gradient from 19.6 +/- 12.4 to 3.8 +/- 5.3 mm Hg. In three patients the blade septostomy was unsuccessful for technical reasons and the condition of the patient. Complications included one death due to atrial laceration, blood loss requiring transfusion in 5 patients, transient CVA in one patient, and failure of the blade to close in one patient. We have found the palliative use of the blade catheter in conjunction with balloon atrial septostomy to be an effective and safe procedure.

Results of repeat percutaneous balloon valvuloplasty for pulmonary valvar restenosis.

Follow-up cardiac catheterization studies were used to evaluate 105 patients who had undergone percutaneous balloon pulmonary valvuloplasty. Fifteen of those patients who had peak systolic pulmonary valve gradients greater than = 40 mm Hg at follow-up underwent repeat balloon valvuloplasty. For the initial balloon pulmonary valvuloplasty, the mean ratio of the balloon diameter to pulmonary valve annulus diameter was 0.98 +/- 0.2; at repeat valvuloplasty the mean was 1.19 +/- 0.12. The immediate post-repeat balloon valvuloplasty results showed a reduction in the peak systolic gradient from a mean of 70.2 +/- 17.8 to 29.1 +/- 19.0 mm Hg (p less than 0.001). This reduction in the gradient was maintained at a mean of 14.3 +/- 5.0 mm Hg in 8 of the 10 patients who underwent further follow-up studies. We conclude that successful repeat balloon pulmonary valvuloplasty with the use of larger sized balloons is feasible in patients who have restenosis after the initial percutaneous balloon valvuloplasty--including partial but not complete dysplasia of the pulmonary valve.

Transseptal left heart catheterisation in infants, children, and young adults.

Over a 5 yr period, from October 1983 to September 1988, transseptal left heart catheterisation, using Mullins long-sheath technique, was performed in 217 infants, children, and young adults, with various forms of congenital or acquired heart disease. The mean age was 50 +/- 45 months, (range 1 mo to 21 yr). The procedure was successful in 215 (99%) patients. Pericardial puncture occurred in three patients (1.4%), though without tamponade or sequelae. There was no mortality or morbidity. Transseptal left heart catheterisation is a safe procedure for studying the left side of the heart. In addition, and of increasing importance, it allows the performance of interventional procedures on the left side of the heart and avoids the use of retrograde catheterisation through the femoral arteries.

Percutaneous catheter closure of the ductus arteriosus in children and young adults.

The double-disk occluding device suitable for use in infants and children with patent ductus arteriosus, developed by Rashkind and Mullins, has been available to this institution since December 1987 on an investigational basis. Results of 43 nonsurgical ductal closure attempts using this device in children and young adults between December 1987 and October 1988 are presented. Successful implantation was achieved in 42 patients (98%). In 25 patients a residual shunt was seen on angiography immediately after implantation. In 12 patients a residual ductal shunt was detected by Doppler 24 hours after implantation; 6-week follow-up studies showed a small residual shunt in only 3 patients. After a second occluder device was implanted in 2 of these patients, complete closure of the patient ductus arteriosus was achieved. In 1 patient, early in the series, the occluder device embolized to the left pulmonary artery, necessitating surgical removal at the time of ductus division. This event was the only serious complication; there were no deaths.

Critical pulmonary valve stenosis in patients less than 1 year of age: treatment with percutaneous gradational balloon pulmonary valvuloplasty.

A new technique of percutaneous gradational balloon pulmonary valvuloplasty was used successfully in 17 infants less than 1 year of age, including four neonates, with critical congenital pulmonary valve stenosis, who would otherwise have required surgical intervention. This technique uses a sequential series of balloon catheters of gradually increasing size as a means of eventually crossing the very small valve orifice with a balloon catheter of adequate size to achieve successful pulmonary valvuloplasty. The initial dilatations were achieved with balloon catheters 2, 3, or 4 mm in diameter. Immediately after successful balloon valvuloplasty, the mean pulmonary systolic pressure gradient was reduced from 105 +/- 11 to 20 +/- 5 mm Hg. Percutaneous balloon pulmonary valvuloplasty can be performed safely with good results despite critical congenital pulmonary valve obstruction in severely ill infants.

Brucella infective endocarditis. Successful combined medical and surgical therapy.

Five cases of Brucella infective endocarditis are described involving a native aortic valve, two native mitral valves, a mitral valve bioprosthesis, and a ventricular septal defect patch. The diagnosis of Brucella infective endocarditis was established from the clinical features, with a high Brucella serologic titer in each case. Blood and tissue cultures were positive in four of five patients. Two-dimensional echocardiograms demonstrated moderately large vegetations on the three affected native valves and the patch and also revealed the development of vegetation on the mitral bioprosthesis as the disease progressed. All the patients were successfully treated by combined surgical and medical therapy, the latter consisting of co-trimoxazole, tetracycline, and streptomycin/gentamicin for 6 weeks; the affected valves and the ventricular septal defect patch were all replaced. There were no operative deaths and there has been no recurrence of infection to date. One patient died suddenly of an unknown cause 1 year after the operation.