Aorta-pulmonary artery shunts with expanded polytetrafluoroethylene (PTFE) tube

Ascending aorta to right pulmonary artery interposition shunt in critically ill infants

In spite of a trend toward earlier complete repair, some neonates and infants with complex cyanotic heart disease continue to require interim palliation with systemic-to-pulmonary artery shunts. A variety of shunt procedures have been proposed, each with inherent advantages and disadvantages. We have found a prosthetic interposition shunt between the ascending aorta and right pulmonary artery (AA-RPA) to be effective in very young infants with small vessels. Over a 15-year period, 51 patients, mean weight 3.33 kg and mean age 59 days, underwent this procedure with a 13% perioperative mortality and a 78% 2-year overall shunt patency rate. We conclude that the AA-RPA interposition shunt is a safe, effective procedure in these infants.

Optimal flow of aorta-pulmonary artery shunt in patients with cyanotic heart disease

An aorta-pulmonary artery shunt with an expanded polytetrafluoroethylene (Gore-Tex) tube graft (3 to 6 mm in diameter) was done in 33 cyanotic patients with complex congenital heart disease. The patients ranged from 14 days to 22 years old. In 28, the shunt flow (QB) was measured, and the optimal QB and graft size were determined. Nine patients had severe heart failure because of an excessively large shunt. Seven of these patients died, 5 early and 2 late after operation. The QBS in these 9 patients were extremely high; the QB index and the ratio of shunt flow to systemic flow (QB/QS) were 3.86 +/- 0.91 L/min/m2 (mean +/- standard deviation) and 52.4 +/- 9.7%, respectively. The QB index and the QB/QS of patients without severe cardiac failure were 1.49 +/- 0.92 L/min/m2 and 27.2 +/- 11.4%, respectively. In conclusion, the QB index, the QB/QS, or both should be maintained in the range of 1.6 to 2.4 L/min/m2 and 30 to 40%, respectively. In infants, however, it is advisable to control the flow at less than the range just given. Analysis of graft size in relation to body weight (BW, in kilograms) and body surface area (BSA, in square meters) showed that the optimal diameter (D, in millimeters) could be calculated by the following formulas: D = 1.88 In(BW) + 1.8 (r = .86) D = 0.87 In(BSA) + 5.3 (r = .73).

Palliation in cyanotic congenital heart disease. Fifteen years' experience of various shunt procedures

During the past 15 years, 143 systemic pulmonary shunt procedures have been performed in 117 patients. These have been evaluated for their clinical effectiveness, the need for a repeat operation and the mortality; particular attention was paid to the Teflon shunt. Variations were found in shunt performance, depending on the primary defect, the type of shunt that was employed and the year of operation. The overall shunt patency after three years was 77% (85% with the Teflon shunt). Although, in our total experience, mortality at 30 days was 12%, with 16% late deaths, "modified Blalock" (Teflon) shunts had only a 5% hospital mortality and a 5% late mortality within three years. Pulmonary atresia, without a ventricular septal defect, is often insufficiently palliated by a shunt alone. Ten of 82 patients with variations of the tetralogy complex died within 30 days of operation, and a further 11 died in the late follow-up period. Six of these 21 shunts were patent at autopsy. Less common defects, such as univentricular heart, transposition and double-outlet right ventricular connections, that are associated with pulmonary stenosis had no early mortality but led to four late deaths among 27 patients. Two of the four patients had patent shunts. Results in the early part of this experience were less than acceptable owing to inferior shunting techniques, postoperative management errors and, particularly, inadequate follow-up surveillance. With correction of these factors we find that the modified Blalock shunt provides very good early and late mortality results, with excellent clinical palliation and patency rates.

Experience with polytetrafluoroethylene grafts in children with cyanotic congenital heart disease

Survival and event-free rates of 47 polytetrafluoroethylene (PTFE) (Gore-Tex) shunts for severe cyanotic congenital heart defects were studied in 42 children from April, 1981, to March, 1983. Retrospective actuarial analysis was conducted over the 27 months of the study in 3-month intervals of the follow-up. The estimated actuarial patient survival at two years was 86% with an estimated actuarial event-free rate of 57.2%. The grafts were found to be patent in 89% (42/47) of the grafts. Complications associated with PTFE grafts were thrombosis, infections, heart failure, shunt stenosis, and deformity of the pulmonary arteries. Polytetrafluoroethylene grafts for systemic-pulmonary shunts offer good palliation, but the frequency of complications indicates that close follow-up is mandatory to avoid or treat serious sequelae of the complications.

Technique and experience with azygos patch modified Blalock-Taussig anastomosis for congenital cyanotic heart disease

Seventeen patients 1 day to 28 months old with congenital cyanotic heart disease underwent a modification of the Blalock-Taussig shunt. Eight were newborn infants weighing 2.6 to 4.8 kg. All infants had complex congenital heart defects that were not considered amenable to early correction. There were no early deaths and no shunt failures. Postoperative complications were restricted to prolonged intubation in 2 patients and a subcutaneous wound infection in a 14-day-old infant. Follow-up from 1 to 31 months revealed minimal cyanosis, stable hemoglobin levels, and good shunt murmurs, and there have been no upper extremity complications. There were 2 late deaths; 1 (the oldest patient) was related to medication, and the second resulted from small bowel necrosis. The concept of the azygos vein patch modified Blalock-Taussig shunt involves two factors: (1) mobilizing as much length as possible of the subclavian artery in spite of its distal small size to allow for a tension-free shunt to prevent tension on the anastomosis as growth occurs, and (2) enlarging the subclavian artery distal to the vertebral artery origin with an autologous azygos patch. During performance of a standard Blalock-Taussig shunt, a longitudinal incision is made through the pulmonary artery across the anastomosis into the upper subclavian artery. The appropriate length of harvested azygos vein is used as a patch angioplasty across the shunt. A tension-free shunt with a patulous distal portion is achieved. Pulmonary overcirculation is avoided by the limiting size of the proximal subclavian artery. Temporary occlusion of the shunt at operation resulted in an increased mean blood pressure from 6 to 18% in all infants.(ABSTRACT TRUNCATED AT 250 WORDS)

A comparison of Blalock-Taussig, Waterston, and polytetrafluoroethylene shunts in children less than two weeks of age

Results obtained with Blalock-Taussig, Waterston, and polytetrafluoroethylene (PTFE) shunts were compared in 67 cyanotic infants less than 2 weeks of age. A different shunt was preferably used at each of three institutions. The incidences of early shunt failure (3 out of 21, 14%), mortality after revision of early shunt failure (0 out of 3), and overall hospital mortality (1 out of 21, 5%) were all lowest for the PTFE shunt. Incidence of congestive heart failure secondary to excessive flow was comparable for the Blalock-Taussig and PTFE shunts, both of which were lower than the Waterston shunt. Cumulative probabilities of late shunt adequacy were calculated for hospital survivors. At 1 year, all shunts provided comparable adequate palliation (greater than 80%). Probability of late shunt failure was significantly higher (p = 0.04) for the PTFE shunt at 3.5 years. Results suggest that the PTFE shunt may be the safest and most effective shunt in neonates, but that elective shunt replacement or total repair may be warranted in the first or second year of life.

Subclavian-pulmonary artery shunts with polytetrafluorethylene interposition grafts

Systemic-pulmonary artery shunts remain an important treatment in cyanotic patients. Central shunts continue to pose early and late problems when standard Blalock-Taussig shunts are not possible. Twenty patients underwent subclavian-pulmonary artery shunt procedures with polytetrafluoroethylene (PTFE) prostheses between October, 1980, and August, 1982. Their ages ranged from 1 day to 15 years; 11 patients were less than 14 days old. The arterial oxygen tension rose from 30.7 +/- 11.9 mm Hg to 51.3 +/- 9.1 mm Hg (standard deviation; p less than 0.001) and from 26.4 +/- 7.5 mm Hg to 50.5 +/- 9.3 mm Hg (p less than 0.001) among the 11 neonates. There were no hospital deaths and only 2 late deaths (not shunt related). All patients have patent shunts and excellent relief of cyanosis. The 18 survivors have been followed for an average of 19 months (range, 7 to 29 months). No patient has required reoperation for shunt inadequacy or thrombosis. Recatheterization in 11 patients has demonstrated normal pulmonary pressures and good pulmonary artery growth without vessel distortion. Subclavian-pulmonary shunts using PTFE provide long-term palliation in cyanotic patients. This type of shunt appears to offer important advantages over other shunt procedures, including the classic Blalock-Taussig operation, in newborns.

Septic involvement of polytetrafluoroethylene (PTFE) anastomoses producing false aneurysms: diagnosis and problems related to management

Two patients with polytetrafluoroethylene (PTFE) grafts developed mycotic aneurysms at the suture lines. Both patients had chronic illnesses and recurrent infections. Attempts to surgically treat these aneurysms were unsuccessful. Infections involving PTFE grafts used in the management of children with congenital heart disease have not been reported. Problems related to diagnosis and management are discussed.

Experience with the modified Blalock-Taussig operation using polytetrafluoroethylene (Impra) grafts

Between June 1978 and January 1982, 115 patients underwent 122 subclavian artery-pulmonary artery shunts using polytetrafluoroethylene (PTFE Impra) grafts. Forty-six of the patients had a ductus dependent pulmonary circulation, the patency of which was maintained by an infusion of prostaglandin E2 in 29 cases. There were nine hospital deaths, four of which were related to shunt failure. Five patients underwent a second shunt procedure within one week of the first. There were two cases of late graft occlusion. Twelve shunts were considered to have failed. The actuarial estimate of shunt patency was 90% (+/- 3%) at two years for all patients and 74% (+/- 10%) for neonates. There was no statistically significant difference in two year shunt patency between 4 mm grafts (88 +/- 5%) and 6 mm grafts (96 +/- 3%). The modified Blalock shunt using a PTFE graft is an effective pulmonary-systemic shunt with a good short term patency.

Alprostadil (Prostin VR Pediatric Sterile Solution, The Upjohn Company)

Alprostadil is a naturally occurring prostaglandin used in the treatment of infants with congenital heart defects to maintain the patency of the ductus arteriosus until palliative or corrective surgery can be performed. In infants with defects restricting pulmonary blood flow (cyanotic), alprostadil improves arterial blood oxygenation. In infants with defects restricting systemic blood flow, alprostadil improves arterial blood pH, urine output, and femoral arterial pulses. Alprostadil is administered by continuous intraarterial or intravenous infusion, usually at a starting dose of 0.1 microgram/kg/min, with maintenance doses as low as 0.002 microgram/kg/min. The most common side effects include fever, apnea, flushing, bradycardia, hypotension, and seizures; although in some cases, some of these effects may be related to the infant's underlying condition. Literature reports of clinical experience with alprostadil are reviewed.

Systemic-Pulmonary shunts inneonates and infants using microporous expanded polytetrafluoroethylene: immediate and late results

Thirty infants with various types of cyanotic congenitl heart disease underwent systemic-pulmonary artery shunts with a microporous polytetrafluoroethylene (PTFE) graft between May, 1976, and July, 1979. Sixteen of them were less than 1 month old, and the average age of the neonates was 5.3 days. There were no operative deaths and 5 hospital deaths, 2 related directly to the shunt. Five patients required early revision of the shunt. Relief from cyanosis was achieved in each patient. Twenty-five patients have been followed up to three and one-half years. There have been 2 late deaths and one late occlusion of the shunt. One patient outgrew the shunt and required secondary shunting procedures. Three of 30 patients have evidenced mild congestive heart failure, which has responded to digitalis. Because of the reliability and excellent late patency of the PTFE prosthesis, we consider it to be superior to a central or Potts shunt for relief from cyanosis in the neonate and infant, and as reliable as a Blalock-Taussig shunt.