Postoperative angiographic assessment of modified Blalock-Taussig shunts using expanded polytetrafluoroethylene (Gore-Tex)

Transcatheter implantation of covered stents serving as extravascular conduits-Proof of a CT-based approach in three cases

BACKGROUND

Covered stents perform similar to surgically implanted conduits, although the stents work inside of vessels. We present a computed tomography (CT)-based workflow for the implantation of covered stents as extravascular conduits.

METHODS

We selected three different use cases: 1. Connecting a left-sided partially anomalous drainage of a pulmonary vein to the left atrium. 2. Bypassing an outgrown Dacron conduit in aortic recoarctation. 3. Re-directing hepatic venous blood to the left lung in a Fontan patient with heterotaxy, connecting the innominate vein to the right pulmonary artery like a right-sided cavopulmonary connection. By postprocessing and analyzing CT scans for planning and by the use of long needles under biplane fluoroscopy for the realization of the procedure, we projected and performed the exit of a long needle out of a vessel, the re-entering of a target vessel, and the bridging of the extravascular distance by implantation of covered stents.

RESULTS

In all three cases, the covered stents were placed successfully, connecting vessels of 15-50 mm distance from each other with very good hemodynamic results. In one case, two stents were placed consecutively, overlapping each other to accomplish an exact fitting at the connection sites to the native vessels.

Comparison of diameter and length of subclavian arteries to external jugular veins in variably sized dogs: A cadaveric study

OBJECTIVE

To evaluate the length and diameter of a left external jugular vein graft as a substitute for the left subclavian artery in the modified Blalock-Thomas-Taussig shunt (mBTTS) in differently sized dogs.

STUDY DESIGN

Cadaveric study.

ANIMALS

Dog cadavers of three weight categories (10/group): <9.5 kg, 9.5 to 27 kg, and > 27 kg.

METHODS

The length and infused external diameters of harvested vessels were measured with vernier calipers and recorded. A matched-pairs t test was used to test the difference in vessel lengths. The agreement in vessel diameters was assessed by using Lin's concordance correlation coefficient (CCC). Pearson's correlation coefficients (CC) were determined for vessel diameter to weight category and vessel length to weight category.

RESULTS

The external jugular vein measured longer than the subclavian artery in all dogs (52.0 ± 20.8 mm and 23.0 ± 8.9 mm, respectively), with a mean difference of 28 ± 14.3 mm (P < .001). The mean external infused subclavian and external jugular diameters measured 7.8 ± 2.2 mm and 8.0 ± 2.5 mm, respectively (P = .32). Lin's CCC was 0.87. Pearson's CC were 0.74 in both vessel diameters (P < .001); they were 0.36 and 0.43, respectively, for subclavian artery and external juglar vein length (P < .001).

CONCLUSION

Autologous external jugular vein grafts had an external diameter similar to subclavian artery and a significantly longer length in variably sized dogs.

CLINICAL SIGNIFICANCE

External jugular vein grafts may be an acceptable graft choice for mBTTS.

Bleeding and Thrombotic Emergencies in Pediatric Cardiac Intensive Care

Children in the cardiac intensive care unit (CICU) with congenital or acquired heart disease are at risk for hematologic complications, both hemorrhage and thrombosis. The overall incidence of hematologic complications in the CICU is unknown, but risk factors and target groups have been identified where the essential physiologic balance between bleeding and clotting has been disrupted. Although the best management of life-threatening bleeding and clotting is prevention, the cardiac intensivist is often faced with managing life-threatening hematologic events involving patients from within the unit or those who present from outside. Part I of this review deals with the propensity of children with congenital and acquired heart disease to complications of both bleeding and clotting, and includes discussions of perioperative bleeding, thromboses in single-ventricle patients, clotting of Blalock-Taussig shunts and thrombotic complications of mechanical valves. Part II deals with the subject of stroke in children with heart disease. Part III reviews monitoring the effectiveness of anticoagulation and thrombolysis in the CICU. Currently available diagnostics modalities, medications and management strategies are reviewed and future directions discussed.

Occlusion of modified Blalock-Taussig shunt after clopidogrel cessation

It has been suggested previously that rebound hypercoagulability may be responsible for morbidity and mortality following clopidogrel cessation in adults with acute coronary syndrome. We report a case of acute occlusion of a modified Blalock-Taussig shunt in an infant after clopidogrel discontinuation.

Outcome of the construction of a Blalock-Taussig shunt in adolescents and adults

AIMS

The purpose of our study was to ascertain the outcome of the construction of a Blalock-Taussig shunt in patients aged 12 years and over.

PATIENTS AND METHODS

We identified 21 patients in whom a Blalock-Taussig shunt had been constructed subsequent to the age of 12 years. Of the patients, 9 were female, and their median age was 18.5 years, with a range from 12 to 46 years. All had usual atrial arrangement, and the atrioventricular connections were concordant in 11, with univentricular atrioventricular connection in 10. Pulmonary atresia was present in 8 (38 per cent), and pulmonary stenosis, either valvar or subvalvar, in 13. An interposition graft had been placed between the subclavian and pulmonary arteries in 16 patients, and an end-to-side anastomosis between the arteries in 5.

RESULTS

One patient had died in hospital, while 4 patients had died during the period of follow-up after initial construction of the shunt. Long-term follow-up was available in 86 per cent of patients. In the 3 patients lost to follow-up, the shunt had been known to be functioning at periods of 4, 8, and 10 years, respectively. Actuarial freedom from death after a period of 17 years was 76 per cent. In 8 patients, a period of 10 years had elapsed with the shunt patent, and a further 10 had a patent shunt after 5 years follow-up. Symptomatic improvement was reported in 16 (76 per cent) patients, although adverse cardiac events had occurred during follow-up in 17, including congestive heart failure in 3, atrial fibrillation in 3, and endocarditis in 2. In 2 patients, it had been possible to proceed to biventricular repair, one with tetralogy of Fallot, and the other having a Rastelli procedure. Further in 3 patients, it had been possible to construct the Fontan circulation, or one of its variants. One patient has undergone cardiac transplantation, while 2 are awaiting transplantation.

CONCLUSIONS

Symptomatic improvement can be achieved by construction of a Blalock-Taussig shunt in older subjects, and the risks of surgery are low. Later repair may be feasible in some patients, but adverse cardiac events may follow the increased volume load on the systemic ventricle.

Obstruction in Modified Blalock Shunts: A Quantitative Analysis With Clinical Correlation

BACKGROUND

Despite numerous reports describing the clinical course of patients undergoing a modified Blalock-Taussig shunt (MBTS), there is limited information on shunt obstruction. No studies have quantified MBTS stenosis histopathologically and correlated that with demographic and clinical risk factors.

METHODS

From June 2001 to June 2003, 155 patients had MBTS takedown. The shunt operation (at median age 6 days; shunt size 3.5 mm in 56 [36%]; 4 mm in 84 [54%]; 5 mm in 15 [10%]) was performed on cardiopulmonary bypass (CPB) in 96 patients (62%). At elective takedown (at median 8.1 months), the shunt was excised and histopathologically analyzed for maximal narrowing. Demographics and clinical variables including age, weight, shunt size and duration, diagnosis, use of cardiopulmonary bypass, blood products, anastomosis sites, and concomitant antegrade flow were then tested for correlation with shunt stenosis.

RESULTS

The mean value for maximal narrowing of the shunt lumen was 34% +/- 22%, and 32 patients (21%) had greater than 50% stenosis. Myofibroblastic proliferation, often associated with organized thrombus, caused the obstruction. Smaller shunt size (<4 mm) was a statistically significant risk factor for stenosis greater than 50% (odds ratio [OR] = 2.51; p = 0.028). Other variables that showed a clinically important association with obstruction but did not reach statistical significance included age less than 14 days at shunt (OR = 2.08, confidence interval [CI] 0.8 to 5.2), shunt on bypass (OR = 2.07, CI 0.9 to 4.8), and platelet use at shunt operation (OR = 1.96, CI 0.9 to 4.4).

CONCLUSIONS

Most MBTS develop stenosis by the time of takedown, and 21% have greater than 50% obstruction. Shunt size less than 4 mm is a risk factor for high-grade stenosis. Younger age, CPB, and use of platelets are other clinically important factors. Better conduits and suppression of intimal proliferation could potentially improve outcomes.

Does the Site of Insertion of a Systemic-Pulmonary Shunt Influence Growth of the Pulmonary Arteries?

BACKGROUND

The modified Blalock-Taussig shunt is a common palliative procedure for children with cyanotic congenital heart disease. The distal shunt anastomosis can be done to a branch pulmonary artery or to the main pulmonary artery. The purpose of this study was to determine if the site of shunt connection influences pulmonary artery growth.

METHODS

The records of 101 patients with a modified Blalock-Taussig shunt undergoing a subsequent cardiac catheterization between January 2000 and April 2002 were retrospectively reviewed. From the cineangiograms, the diameters of the right and left pulmonary arteries at their first branching and the diameter of the descending aorta at the diaphragm were measured.

RESULTS

If the distal shunt anastomosis was to the right pulmonary artery and there was no antegrade pulmonary flow then the left pulmonary artery was significantly smaller than if the distal connection was to the main pulmonary artery (p = 0.009). Absence of antegrade pulmonary blood flow resulted in significantly smaller right and left pulmonary artery size in general (p < 0.001). No significant differences in pulmonary artery growth were found with respect to gender, anatomic subtype, proximal shunt site, use of cardiopulmonary bypass or size of shunt. By multiple regression analysis absence of antegrade flow and the presence of right-sided shunts were statistically significant predictors of smaller left pulmonary artery and size discrepancy between right and left pulmonary artery.

CONCLUSIONS

These data suggest that in the absence of antegrade pulmonary blood flow, a modified Blalock-Taussig shunt to the main pulmonary artery may promote more uniform branch pulmonary artery growth.

Tetralogy of Fallot

The optimal surgical approach and timing for patients with tetralogy of Fallot remain controversial. There are two options in current practice: a two-stage repair (an initial palliative aortopulmonary shunt at an early age followed by complete repair at an older age) or primary complete repair. There has been a trend towards primary repair at a young age, which can be attributed to advances in anesthetic and cardiac surgical techniques. Primary repair has several advantages. The correction can be done in one operation and shunt complications are avoided. Progressive right ventricular fibrosis, ventricular hypertrophy, and chronic hypoxia are avoided, which may reduce the incidence of late ventricular arrhythmias. However, surgical correction at a young age is associated with an increased incidence of transannular patching and consequent pulmonary regurgitation. Progressive pulmonary regurgitation is associated with late ventricular arrhythmias and sudden death. These consequences may be prevented by timely pulmonary valve replacement. Palliative procedures include an aortopulmonary shunt, balloon dilation of the right ventricular tract, and stent placement. Of these measures, the aortopulmonary shunt is preferred, as it results in a more predictable outcome. Complications associated with shunt placement include shunt occlusion, pulmonary artery distortion, and occasionally, volume overloading of the left ventricle and pulmonary circulation. Institutional and surgeon preferences exist for either surgical strategy, and ultimately are justifiable when they produce the best outcomes for the individual patient. The optimal surgical strategy has to be determined by large prospective randomized studies that compare the functional status of the pulmonary valve and the need for reoperation at long-term follow-up.

Thoracic and thoracoabdominal aneurysm repair under deep hypothermia using subclavian arterial perfusion

BACKGROUND

Hypothermic circulatory arrest is a valuable adjunct for thoracic and thoracoabdominal aortic aneurysm repair. Retrograde aortic perfusion through the femoral artery, however, carries a risk of cerebral embolism or malperfusion. To avoid these complications we adopted antegrade aortic perfusion through a prosthetic graft attached to the left subclavian artery through a left thoracotomy.

METHODS

Ten patients had repair of descending thoracic and thoracoabdominal aortic aneurysm under deep hypothermia with antegrade aortic perfusion through the left subclavian artery. Hypothermic circulatory arrest was used because proximal aortic control was hazardous due to rupture or intraluminal disease, or for spinal cord protection.

RESULTS

There was no brain injury and one hospital death. The cause of death was massive bleeding from the gastrointestinal tract not related to deep hypothermia or the perfusion method. All 9 survivors were alive and well after a mean follow-up period of 9 months.

CONCLUSIONS

Using the left subclavian artery as a site of aortic perfusion can avoid retrograde aortic perfusion, hence reducing the potential for brain injury due to embolic stroke or malperfusion through a dissected thoracoabdominal aorta.

Reduced frequency of occlusion of aorto-pulmonary shunts in infants receiving aspirin

OBJECTIVE

Infants with severely reduced pulmonary perfusion due to complex congenital cardiac malformations are in need of an improved flow of blood to the lungs. One option for treatment is to construct a systemic-to-pulmonary arterial shunt. Although such shunts have been used since 1945, their spontaneous occlusion remains a major problem in the long-term.

DESIGN

We studied all infants in whom a systemic-to-pulmonary arterial shunt had been constructed using a Gore-Tex tube graft between December 1989 and March 1996.

PATIENTS

Of 46 infants undergoing construction of a shunt, 7 (15%) died within 30 days of surgery. The shunts had to be taken down in 2 infants. Thus, 37 infants were included in the study. All but three infants received Aspirin. Aspirin was discontinued on the personal decision of individual physicians. Of 22 infants, 3 never received Aspirin, and in 19 it was stopped well before undertaking subsequent surgery. Aspirin was administered continuously to 15 infants until further surgery.

RESULTS

Those in whom Aspirin was discontinued, or not given, and those receiving Aspirin until further surgery, were comparable concerning their age, time of follow-up, severity of the cardiac lesions, and size and type of shunt. Partial or complete occlusion of the shunt occurred in 2 of 15 (13%) infants taking Aspirin, but was seen in 12 of 22 (54%) infants in whom Aspirin was discontinued. Of these, 3 died due to acute occlusion of the shunt.

CONCLUSIONS

Aspirin reduced effectively the rate of occlusion of systemic-to-pulmonary arterial shunts, and should be continued as long as the shunt is in place.

Effects of modified and classic Blalock-Taussig shunts on the pulmonary arterial tree

BACKGROUND

The aim of this study was to assess by angiography the late effects of both classic and modified Blalock-Taussig shunts in terms of growth and development of stenosis and distortion.

METHODS

At a mean of 51 months postoperatively, we retrospectively reviewed the results in 78 patients who underwent creation of Blalock-Taussig shunts (25 classic and 71 modified).

RESULTS

At the level of the anastomosis, the shunt caused a reduction in diameter of the pulmonary artery in 49% of all shunts, major stenosis (>50% narrowing of the lumen) in 14%, and distortion of the pulmonary artery in 19%, findings that did not correlate with the type of shunt. Distortion did correlate with younger age at the time of shunt operation (p=0.01).

CONCLUSIONS

After a Blalock-Taussig shunt, growth of the pulmonary arteries occurred but did not exceed the normal growth of the pulmonary arterial tree. Moreover, a shunt procedure can cause distortion and stenosis of the pulmonary artery, which may have important implications for future corrective surgical intervention. All these findings support earlier complete surgical repair of correctable congenital cardiac defects.

Transaxillary minithoracotomy for modified Blalock-Taussig shunt

A technique that allows construction of a modified Blalock-Taussig shunt using a polytetrafluoroethylene graft in neonates and infants through an axillary vertical minimal access thoracotomy is described. It is a simple, safe, cosmetically acceptable, and efficient approach even when used during emergency situations. It was successfully performed in 5 neonates and infants.

Early balloon dilatation of the pulmonary valve in infants with tetralogy of Fallot. Risks and benefits

BACKGROUND

Balloon dilatation, an established treatment for pulmonary valve stenosis, remains a controversial procedure in tetralogy of Fallot.

METHODS AND RESULTS

Balloon dilatation of the pulmonary valve was performed in 19 infants with tetralogy of Fallot. Its effects on the severity of cyanosis, the growth of the pulmonary valve and pulmonary arteries, and the need for transannular patching were evaluated. Clinical, echographic, angiographic, hemodynamic, and operative data were analyzed. The procedure was safe in all, without significant complications. After balloon dilatation, systemic oxygen saturation increased from a mean value of 79% to 90%. This increase proved to be short-lasting in 4 patients, who required surgery before the age of 6 months. Balloon dilatation increased pulmonary annulus size in each case, from a mean value of 4.9 to 6.9 mm (P < .001). This gain in size remained stable over time, with a mean Z score of -4.8 SD before dilatation, -3.1 SD immediately after the procedure, and -2.7 SD at preoperative catheterization (P < .001). Pulmonary artery dimensions remained unchanged immediately after balloon dilatation but increased at follow-up from a Z score mean value of -2.5 to -0.06 SD and from -2.2 to 0.04 SD for right and left pulmonary arteries, respectively (P < .001). At the time of corrective surgery, the pulmonary annulus was considered large enough to avoid a transannular patch in 69% of the infants. This represented a 30% to 40% reduction in the need for a transannular patch compared with the incidence of transannular patch expected before balloon dilatation.

CONCLUSIONS

Pulmonary valve dilatation in infants with tetralogy of Fallot is a relatively safe procedure and appears to produce adequate palliation in most patients. It allowed the growth of the pulmonary annulus and of the pulmonary arteries, resulting in a mean gain of 2 SD for those structures.

Transcatheter treatment of pulmonary outflow tract obstruction: a review

The role of transcatheter methods in the management of pulmonary outflow tract obstruction are discussed in this review. Balloon pulmonary valvuloplasty for relief of isolated pulmonary valve stenosis has been successfully used by many investigators and is the procedure of choice for the management of these lesions. Supravalvar pulmonic stenosis, if discrete, can be relieved by balloon dilatation. Cyanotic children with interatrial right-to-left shunts secondary to severe valvar pulmonary stenosis respond in a manner similar to that observed with isolated pulmonary valve stenosis. In these patients, balloon valvuloplasty is the treatment of choice and may be corrective in most patients. In patients with interventricular right-to-left shunting secondary to pulmonary outflow tract obstruction and in patients with narrowed BT shunts, balloon dilatation may be an effective palliative procedure in a substantial proportion of patients obviating the need for an initial or second palliative shunt. Balloon dilatation is recommended if the patient's size or cardiac anatomy make them unsuitable for safe total surgical correction. In patients with pulmonary atresia, either initial opening of the atretic pulmonary valve by laser or by surgery with subsequent balloon dilatation are potentially beneficial in reducing the total number of surgical procedures that these children are likely to require. However, further clinical trials are needed before their general use.

Transcatheter management of cyanotic congenital heart defects: a review

In this review, the role of transcatheter methods in the management of cyanotic congenital heart defects is discussed. In patients with interventricular right-to-left shunting secondary to pulmonary outflow tract obstruction (most commonly tetralogy of Fallot), balloon dilatation may be an effective palliative procedure in a substantial proportion of patients, obviating the need for a palliative shunt. We would recommend this if the patient's size or cardiac anatomy makes that patient an unsuitable candidate for safe total surgical correction. Infundibular myectomy with atherectomy catheter in tetralogy of Fallot patients may become a useful adjunct in the management of these infants. Cyanotic children with interatrial right-to-left shunt secondary to severe valvar pulmonary stenosis respond to balloon pulmonary valvuloplasty in a manner similar to that seen with isolated pulmonary valve stenosis. In these patients, balloon valvuloplasty is the treatment of choice and may be corrective in most cases. In patients with a narrowed Blalock-Taussig shunt, balloon angioplasty may improve pulmonary oligemia and systemic arterial hypoxemia and may obviate the need for a second systemic-to-pulmonary artery shunt. Balloon angioplasty is recommended if the patient's cardiac defect is not amenable to surgical correction at a low risk either because of the size of the patient or because of the complexity of the cyanotic heart defect. In patients with pulmonary valve atresia, initial opening of the atretic pulmonary valve by either laser or surgery with subsequent balloon dilatation is potentially beneficial in reducing the total number of surgical procedures that these children are likely to require. However, further clinical trials are needed prior to their general use.

Progress of patients with pulmonary atresia after systemic to pulmonary arterial shunts

Between February 1980 and June 1987, 42 shunts were placed in 39 infants with pulmonary atresia: 33 were modified Blalock-Taussig shunts with polytetrafluoroethylene (PTFE) and 9 were classic Blalock-Taussig shunts. There were four hospital deaths not related to the shunts. The remaining 35 patients were followed up for 1.6 months to 6.3 years (mean, 24.7 +/- 18 months). Repeat cineangiocardiographic studies revealed stenosis or distortion of the pulmonary arteries related to the site of the shunt in 11/22 patients (50%) with PTFE shunts and in 1/6 (17%) with classic Blalock-Taussig shunts; the stenosis was severe in only 1 patient. Mean increase in the pulmonary arterial index in the group with classic Blalock-Taussig shunts was 117 +/- 52 mm2/m2 (not significant) and in the group with PTFE shunts, 158 +/- 21 mm2/m2 (p less than 0.001). Late shunt occlusion occurred in 1 patient 23 months postoperatively. Thereafter, shunt patency rate remained at 94% +/- 6%. At the end of 1 year 81% +/- 7% of patients were judged to have adequate palliation, but between 2 and 3 years, only 60% +/- 10%. Univariate analysis showed that after 2 years the ranking order for successful palliation was classic Blalock-Taussig, 5-mm PTFE, and 4-mm PTFE shunts, but differences did not achieve statistical significance.

Tetralogy of Fallot

Tetralogy of Fallot is the most common malformation of children born with cyanotic heart disease, with an incidence of approximately 10 per cent of congenital heart disease. There can be a wide spectrum as to the severity of the anatomic defects, which include ventricular septal defect, aortic override, right ventricular outflow tract obstruction, and right ventricular hypertrophy. Cyanosis may vary from mild to severe, and patients may present as newborns or, more commonly, young infants. Infants with classic tetralogy of Fallot and stable anatomy should undergo primary complete intracardiac repair. The overall hospital mortality is approximately 3 to 5 per cent, with most patients who survive having an excellent clinical and hemodynamic result.

Tricuspid atresia: current concepts in diagnosis and treatment

Tricuspid atresia is the third most common cyanotic cardiac malformation, seen in 1 per cent of children with congenital heart disease. Anatomic details in each patient can be elucidated by echocardiography. Surgical treatment initially is palliation, usually with aortopulmonary shunt. Definitive treatment is with a Fontan operation, in which the systemic venous return is connected directly to the pulmonary arterial tree. Long-term results of the corrective procedure have been very good.

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).

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.

The surgical treatment of tetralogy of Fallot

This is a review of the last 307 patients with tetralogy of Fallot who were operated on in our unit at Groote Schuur Hospital and Red Cross War Memorial Children's Hospital. Complete repair was undertaken in 301 patients, and shunts were performed in 6 children. There were 17 hospital deaths and 1 late death. The mortality was 5.5% for children less than 12 years old and 6.6% in patients between 12 and 20 years old. During this study period, there was a change in our policy as to when complete repair should be attempted. At present, we perform systemic-pulmonary shunts in patients less than 6 months old and delay complete repair until the child is 2 years old. In deciding whether a shunt should precede complete repair, our experience has shown that age is not as important a consideration as the anatomy of the outflow tract of the right ventricle and pulmonary arteries.

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.

Cardiac surgery in the critically ill infant during the first three months of life

Major advances have been made in the treatment of congenital heart disease in the past 10 years. Management of the 20 per cent of children who become critically ill during the first 3 months of life remains a major challenge because they represent the most extreme anatomic and physiologic derangements. A review of the recent data accumulated in the NERICP showed an overall mortality of 54 per cent in infants presenting for surgery in the first 2 months of life. We have reviewed our experience with over 400 procedures during the past 5 years in infants less than three months of age, and our overall mortality is 19 per cent. Primary repair remains our goal, but a disappointingly high mortality with primary repair in this group, by us and others, has caused us to perform palliative procedures when palliation in our experience offers an overall lower mortality.