Does the modified Blalock-Taussig shunt cause growth of the contralateral pulmonary artery?

BACKGROUND: Although some pediatric cardiology departments have a policy of adopting primary correction of tetralogy of Fallot in all symptomatic infants, we and others still palliate neonates and infants. Effective palliation should ameliorate symptoms and allow growth of the pulmonary arteries. Although studies on the growth of the ipsilateral and contralateral pulmonary arteries after a classic Blalock-Taussig shunt have been reported, pulmonary artery growth after a modified Blalock-Taussig shunt has not been studied as thoroughly. Therefore, we examined whether there is equal growth of the contralateral pulmonary artery after a modified Blalock-Taussig shunt. METHODS: We retrospectively analyzed the records of 140 patients with symptomatic tetralogy of Fallot who had a modified Blalock-Taussig shunt between October 1985 and October 1995. The median age at the time of the Blalock-Taussig shunt was 1.6 months. All patients had corrective procedures at a median age of 1.7 years. Cineangiography was done before the corrective procedure. From the angiograms the diameter of the right and left pulmonary arteries before their first lobar branches and the diameter of the descending thoracic aorta at the level of the diaphragm were measured. For each patient the ratios of right pulmonary artery to descending thoracic aorta and left pulmonary artery to descending thoracic aorta were determined and compared using Student's t test. RESULTS: Of the 140 patients, 114 had a left-sided Blalock-Taussig shunt, 20 had a right-sided shunt, and 6 patients had bilateral shunts. The mean right pulmonary artery to descending thoracic aorta ratio was 1.10 and the mean left pulmonary artery to descending thoracic aorta ratio was 0.98. This difference was not significant. CONCLUSION: We showed equal growth of the right and left pulmonary arteries with no distortion after a modified Blalock-Taussig shunt. If palliation is considered, the modified Blalock-Taussig shunt remains our choice.     

Right lower lobe consolidation: an unusual complication of the modified Blalock-Taussig operation

Persistent right lower lobe consolidation in a 5-year-old girl is described. In infancy she had been diagnosed to have tricuspid atresia and pulmonary stenosis, and she had undergone a modified Blalock-Taussig shunt using a polytetrafluoroethylene tube graft at the age of 1 year. The shunt had parasitized and then occluded the right main bronchus. At bronchoscopy, the shunt was removed. The pneumonia resolved, and the child remains well 10 months later. This complication of the modified Blalock-Taussig shunt, which does not appear to have been reported previously, demonstrates the need for bronchoscopy in unresolving pneumonia in childhood.     

Complete atrioventricular canal and tetralogy of Fallot with pulmonary atresia

Our patient was diagnosed with complete atrioventricular canal and Tetralogy of Fallot with pulmonary atresia at the age of 1 month. Then he underwent right and left Blalock-Taussig shunts at the ages of 2 months and 5 years, respectively. His cyanosis had increased at 20 years of age. Cardiac catheterization showed occlusion of the left Blalock-Taussig shunt and absence of the left pulmonary artery. Lung perfusion scintigram showed late phase perfusion in the left lung. Chest computed tomographic scan demonstrated the left pulmonary artery. We describe the operative technique of total correction.     

Fontan operation through a right lateral thoracotomy to treat Cantrell syndrome with severe ectopia cordis

A median sternotomy would be very difficult for Cantrell syndrome with severe ectopia cordis. For Cantrell syndrome and tricuspid atresia after left modified Blalock-Taussig shunt with severe ectopia cordis, defect in the middle and inferior portion of the sternum, and the closing of ventriculo-peritoneal shunt, we performed extracardiac total cavopulmonary connection through a right lateral thoracotomy after establishing right modified Blalock-Taussig shunt and performing coil embolization of left modified Blalock-Taussig shunt by cardiologists.     

An infected pseudoaneurysm following a modified Blalock-Taussig shunt

A two-month-old male infant with tetralogy of Fallot underwent a right-sided modified Blalock-Taussig shunt using a 4 mm expanded polytetrafluoroethylene graft through a right thoracotomy. Five months later, the patient developed otitis media, followed by repeated relapses of pneumonia and fever of unknown origin. Multidetector-row computed tomography and angiography, performed at 12 months of age, revealed a pseudoaneurysm of the subclavian artery at the insertion of the modified Blalock-Taussig shunt. After 20 days of antibiotic therapy, the pseudoaneurysm and infected graft were successfully resected through a median sternotomy approach. This report describes the treatment strategy of this rare but potentially fatal complication after a modified Blalock-Taussig shunt operation.     

An unusual post-operative complication following modified left Blalock-Taussig shunt

A left modified Blalock-Taussig shunt was performed in a 3-year old child with Fallot's tetralogy. Intraoperative course was uneventful. Persistent hypoxia was noticed in the post-operative period in spite of a clinically functioning shunt. Angiography revealed a functioning shunt with totally blocked left pulmonary artery. A thrombus was removed from the left pulmonary artery which dramatically improved the clinical course of the patient.     

Successful repair of tetralogy of Fallot with severe right ventricular dysfunction using veno-arterial bypass in an adult

A 35-year-old male with tetralogy of Fallot, who had undergone left Blalock-Taussig shunt at ten year old, developed severe dysfunction of right ventricle with decreased right ventricular ejection fraction of 25% and frequent premature ventricular contractions of right ventricular origin. Following intracardiac procedure, the venoarterial assist circulation was successfully employed for 9 hours, until his hemodynamic conditions were improved. This experience reemphasized the importance of right ventricular protection and mechanical circulatory assist in the surgical treatment of Fallot's tetralogy in older children and adults who developed severe right ventricular dysfunction as a natural history of this disease.     

Atrial isomerism: a surgical experience.

Most publications on atrial isomerism are autopsy or case reports. The authors review 41 consecutive children operated on from 1980 through to 1996 with emphasis on associated cardiac anomalies, surgical procedures and outcome. Left atrial isomerism was present in 23 patients. Interruption of the inferior vena cava (56%), atrio-ventricular septal defect (47%), common atrium (38%) and cor triatriatum sinistrum (30%) were the most common diagnoses. Biventricular repair was achieved in 17 children and total cavo-pulmonary connection in two. Three underwent staged palliation: modified Blalock-Taussig shunt for two and bidirectional Glenn anastomosis for one. The remainder received a cardiac pacemaker. One patient died early after repair. Two underwent reoperation to correct a regurgitant left atrio-ventricular valve: one of these, in another hospital, had peroperative death. Three died later. Actuarial survival rate after repair and total cavo-pulmonary connection that was stabilized after 2 years was 84%. In the 18 children with right atrial isomerism, pulmonary atresia or stenosis predominated (89%) with discordant ventriculo-arterial connection (72%), atrio-ventricular septal defect (72%), 'single' ventricle (55%) and extracardiac total anomalous pulmonary venous drainage (50%). Biventricular repair was achieved in two patients and complete Fontan circulation in eight. The other eight underwent various staged palliative procedures and correction of extracardiac total anomalous pulmonary venous drainage. Five patients died postoperatively: two in our unit after modified Blalock-Taussig shunt and total cavo-pulmonary connection, three in other hospitals after repair (n = 1) and Fontan (n = 2). Five died later. One was lost for review. Survival after repair and Fontan stabilized after 6 months at 49%. In conclusion, the cardiovascular malformations associated with left atrial isomerism can often be successfully corrected. Those accompanying right atrial isomerism usually preclude a biventricular repair, require staged palliation and carry a poor prognosis.     

Repair of tetralogy of Fallot in an adult; the importance of preoperative examination for major aorto-pulmonary collateral arteries

We report the repair of tetralogy of Fallot in a 51-year-old man. He underwent a left classical Blalock-Taussig (B-T) shunt when he was ten years old. Preoperative angiography showed a patent B-T shunt. Total corrective surgery was performed. Postoperatively, he suffered from left ventricular failure. Re-intubation was required three times. Postoperative catheterization showed excellent correction of the right ventricular system, however, descending aortography revealed a great many aorto-pulmonary collateral arteries, which caused the left ventricular failure. Coil embolization of these 13 collateral arteries was performed and he recovered from the left ventricular failure. We conclude that even in an elderly patient with tetralogy of Fallot, total correction should be performed, since the surgical risk is acceptable and the procedure improves the capacity for physical activity and quality of life. Preoperative examination of collateral arteries is important, especially in elderly patients, and coil embolization should be considered.     

Cavopulmonary anastomosis as long-term palliation for patients with tricuspid atresia

Prior to 1970, most patients with tricuspid atresia (TA) and reduced pulmonary blood flow were palliated by means of a systemic to pulmonary artery shunt (SPAS). In Birmingham between 1967 and 1988, 19 patients with TA (aged 16 days to 23 years, mean 3.8 years) have undergone side-to-side cavopulmonary anastomosis (CPA) with preservation of pulmonary artery continuity. One had undergone a previous right Blalock-Taussig shunt and in 1 patient with left and right SVCs, bilateral CPAs were performed. Nine patients were less than 1 year old at the time of operation. There were no operative deaths. One late death occurred due to pneumonia. Immediate clinical improvement occurred in all cases. Six symptomatic patients subsequently required further surgery (mean interval between operations 8.9 years, range 4.6–14.2 years). The remaining 12 patients have recently been reviewed. Mean follow-up was 9.5 years (range 5 weeks to 21 years). Exercise tolerance remains good (9 in NY-HA Class 1 or 2) and resting transcutaneous oxygen saturations are higher (mean 85%, range 70%–89%) compared with preoperative values (P < 0.01). In small children, CPA avoids the complications of SPAS and, in some patients, may itself achieve adequate long-term definitive palliation.     

Double outlet right ventricle and pulmonary atresia with a birth weight of 1092 g

A premature infant with double outlet right ventricle and pulmonary atresia with a birth weight of 1092 g is reported. He underwent right modified Blalock-Taussig (RMBT) shunt with an expand-polytetrafluoroethylene (ePTFE) tube of 3.0 mm in diameter between the right subclavian artery and the right pulmonary artery through right thoracotomy. Eleven days later, he had to undergo central shunt between the innominate artery and the main pulmonary trunk due to poor pulmonary blood flow. Soon after the central shunt, severe heart failure occurred due to excessive pulmonary blood flow. RMBT division was performed immediately. He finally attained definitive repair at 17 months of age. Postoperative course was uneventful and he was discharged on the 17th postoperative day.     

The bidirectional cavopulmonary shunt.

The bidirectional cavopulmonary shunt improves systemic arterial oxygen saturation without increasing ventricular work or pulmonary vascular resistance. Since 1983, 17 patients have undergone a cavopulmonary shunt procedure (five primary operations, 12 secondary operations). Diagnoses were single ventricle complex (n = 4), hypoplastic right heart syndrome (n = 10), and hypoplastic left ventricle (n = 3). Age at primary operation ranged from 3 1/2 to 30 months (median 6 months). Weight ranged from 3.5 to 9.7 kg. Age at secondary operation ranged from 10 months to 14 years (median 15 months). Seven cavopulmonary shunt operations were performed without cardiopulmonary bypass (six via thoracotomy and one via sternotomy) and 10, with cardiopulmonary bypass. All patients in the bypass group had additional procedures: takedown of modified Blalock-Taussig shunt, seven patients; revision of right ventricular outflow tract, four patients; reconstruction of pulmonary arteries, four patients; tricuspid valvuloplasty, one patient; and Damus procedure, one patient. There was one (1/17) operative death (Damus procedure). One patient required early revision. Follow-up ranges from 1 to 53 months (median 23 months). Twelve of 16 had a good to excellent late result, with a rise in mean arterial oxygen saturation from 69% to 83%. Three patients died late (4 to 53 months) (pulmonary vascular disease, pulmonary arteriovenous malformations, and pneumonia, one patient each). There was one late failure (converted to Glenn shunt). The cavopulmonary shunt is an excellent palliative procedure when right atrium-pulmonary artery connection (modified Fontan) must be deferred because of age, weight, or anatomic considerations. Five patients have undergone right atrium-pulmonary artery connection later. In addition, at the time of the modified Fontan operation, the cavopulmonary shunt approach may optimize the anatomic connection (eight additional patients).     

Right ventricular aneurysm following modified Norwood-Sano operation for hypoplastic left heart syndrome

Hypoplastic left heart syndrome is a rare congenital heart defect characterized by underdevelopment of left-sided heart structures, including the aortic arch. The contemporary surgical management of this anomaly includes the Norwood procedure and provision of pulmonary blood flow by either a modified Blalock-Taussig shunt (MBTS) or a right ventricle-to-pulmonary artery (RV-PA) conduit, commonly referred to as the Sano shunt. We report on an unusual complication of the Sano shunt, that of a giant right ventricular pseudoaneurysm occurring at the shunt insertion site.     

A case of a patient with the non-confluent main pulmonary artery with the left pulmonary artery after a left Blalock-Taussig shunt for tetralogy of Fallot, which underwent a successful two staged radical repair

We report on a 14-year-old girl with tetralogy of Fallot and the non-confluent main pulmonary artery with the left pulmonary artery after a left Blalock-Taussig shunt. She underwent a left-sided classic Blalock-Taussig shunt at the age of one. However, she showed repeated dyspnea and increasing cyanosis, and cardioangiography showed the non-confluent main pulmonary artery with the left pulmonary artery. Corrective surgery of tetralogy of Fallot was done by a two-staged operation. In the first stage, a EPTFE prosthesis was grafted between the main pulmonary artery and the left pulmonary artery, and in the second stage, intracardiac operation was performed. The late postoperative status and hemodynamic results were satisfactory and we emphasize the rational for this approach.     

Surgical palliation of cardiac malformations associated with right isomerism

Between 1985 and 1993, palliative surgery was performed on 13 pediatric patients who had complex cardiovascular anomalies associated with right isomerism. The patients included two neonates, ten infants, and one child who were divided into two groups according to whether or not a total anomalous pulmonary venous connection (TAPVC) was present. Group 1 consisted of six patients with TAPVC and group 2 consisted of seven patients without TAPVC. In group 1, the surgical procedures involved TAPVC repair alone in two patients, combined TAPVC repair with a modified Blalock-Taussig shunt in two, combined TAPVC repair with pulmonary artery banding in one, and a modified Blalock-Taussig shunt alone in one. There were five hospital deaths and one late death in this group: pulmonary venous obstruction in two patients, perioperative myocardial failure in the two neonates, and congestive heart failure caused by increased pulmonary blood flow in two patients. In group 2, all the patients underwent systemic-pulmonary artery shunts, and there was one hospital death and three late deaths, the causes of which were unknown in two patients, and shunt failure and pneumonia in one patient each. These results suggest that surgical palliation for right isomerism produces poor results in young infants with obstructed TAPVC. Thus, we conclude that TAPVC repair should be performed without delay if pulmonary venous obstruction has been diagnosed clinically. Resolving pulmonary venous obstruction without cardiopulmonary bypass (CPB) may be preferable for infants, considering their difficult management. The systemic-pulmonary artery shunt should be of the low-calibrated type, especially if common atrioventricular valve regurgitation exists. If infants survive the surgery, they must be carefully followed up for a long period due to the risk of sudden death or infection.     

Fontan operation for tricuspid atresia with dysplasia of the right ventricular myocardium and absence of pulmonary valve

We report a case of successful staged repair of tricuspid atresia with dysplasia of the right ventricular myocardium and absence of the pulmonary valve. The patient underwent the modified Blalock-Taussig shunt operation at 1 month the bidirectional Glenn procedure at 11 months, and the total cavopulmonary connection procedure using extracardiac graft at 2 years. It is important to prevent the left ventricular outflow tract obstruction (LVOTO) caused by the non-functioning right ventricle when the Fontan completion. We were safely able to disconnect the pulmonary trunk from the right ventricle using the transesophageal echocardiography to evaluate the LVOTO during operation.     

Classic shunting operations as part of two-stage repair for tetralogy of Fallot.

One hundred forty-nine consecutive patients with tetralogy of Fallot, with or without pulmonary atresia, underwent Blalock-Taussig or Waterston operation for initial palliation. Of these patients, 45 were less than 6 months old, and 63 were less than 1 year old. The type of shunt, and the presence or absence of pulmonary atresia did not have a significant effect (p greater than 0.2) on hospital mortality. Parametric analysis showed a significant effect of age (p = 0.03), the risk of hospital death being 6% at 1 month of age, 4% at 3 months, 3% at 6 months, and 2.5% at 12 months. No late deaths occurred before the age of 3 years. Six patients (4.2% of the hospital survivors) required another operation before they were 3 years old. Severe arm ischemia occurred after a Blalock-Taussig shunt in 1 infant with Down's syndrome.     

Post cardiac surgery phrenic nerve palsy in pediatric patients

From January 1978 to December 1988, 109 phrenic nerve paralyses (PNP) occurred in a total of 9149 cardiac operations performed in a population of patients younger than 15 years old (1.2%) whose age varied from 1 day to 15 years old and mean weight was 11.3 +/- 8.7 kg. PNP was diagnosed in 43 patients after closed procedures (1.2% of 3509 procedures) and in 66 patients after open heart operations (1.2% of 5640 operations). PNP was right sided in 49 cases and left sided in 60 cases. Open heart operations that predisposed to PNP were those which needed harvesting of autologous pericardium (P less than 0.0001) and wide exposure of the great vessels. The modified right Blalock-Taussig shunt was the main cause of PNP in closed procedures (P less than 0.02). Small children tolerated PNP less well. They needed longer ventilatory support (P less than 0.0005) and developed more respiratory complications. Seventeen children underwent plication of the affected hemidiaphragm and could be subsequently extubated. It is concluded that for prevention of PNP, a high level of attention should be exercised in neonates and small children, particularly when pericardium is harvested or when exposure needs extensive dissection of the great vessels and thymus resection, or at reoperation. We also prefer to avoid the use of iced slush lavage. PNP, when symptomatic, is best managed by continuous positive airway pressure (CPAP) ventilation. Diaphragmatic plication is recommended when after 2-3 weeks there is no recovery of diaphragmatic function or when there are troublesome respiratory complications.     

An autopsy case of pinealoma treated by irradiation about four years ago (author's transl)]

The patient was a thirty years old male, who was diagnosed as having pineal body tumors in June,1969, and treated by irradiation after a ventriculo-atrial shunt operation. He recovered well, and participated in some simple work. In May 1972, he suddenly had convulsions followed by incontinence, and he became nearly apallic. Neuroradiological examinations revealed the presence of left frontal tumor, which was removed, on June 22, 1972. Histological examinations of the tumor proved to be pinealoma of two-cell pattern. Though improved slightly after operation, he became apallic again, developed pneumonia, and died on February 22, 1973.     

Double switch operation (Senning and Rastelli operation) with left atrial augumentation by in situ autologous pericardium: a case report]

A 23-month-old female infant with situs solitus, atrioventricular and ventriculoarterial discordance, pulmonary atresia, ventricular septal defect, who had received modfied right Blalock-Taussig shunt (4 mm Gore-Tex tube) at the age of 2 months, was carried out double switch operation with left atrial augumentation by in situ autologous pericardium. The spatial position of the heart was mesocardia. The systemic right ventricular end-diastolic volume was 100% of normal, and the pulmonic left ventricular end-diastolic volume was 105% of normal. Atrioventricular valvular regurgitation was not found. Postoperative course was uneventful. On the 28th postoperative day,she discharged from hospital. The disadvantage of double switch operation is difficulty of atrial switch procedure, because most patients have a small atrium due to dextrocardia or mesocardia. For the purpose of atrial augumentation without artificial materials, our modified Senning procedure is useful. But longer follow-up is necessary to determine whether this technique is indeed beneficial.