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.     

Pleural flap for treating perigraft leak after a modified Blalock-Taussig shunt

Plasa oozing through the graft after a modified Blalock-Taussig shunt is a troublesome complication. We encountered a massive leak following a modified Blalock-Taussig shunt in a 2 1/2 year-old-girl which required reexploration. The leak was treated by wrapping the polytetrafluoroethylene shunt with the parietal pleura flap harvested from the adjacent chest wall. The patient had an uneventful recovery. Covering of the polytetrafluoroethylene shunt with parietal pleura appears to stop plasma leak through the graft following a modified Blalock-Taussig shunt.     

Reoperation of Blalock-Taussig shunt for double outlet right ventricle and pulmonary atresia in an adult

A 36-year-old man was admitted to our hospital due to dyspnea and pneumonia. He had undergone left classical Blalock-Taussig shunt at 5 years old and right modified Blalock-Taussig shunt at 16 years old, because he was judged as no indication for any radical operation. Since the last surgery, he had stopped visiting hospital. Computed tomography showed pneumonia and pulmonary embolism in the left lower lung and occlusion of the right modified Blalock-Taussig shunt. After pneumonia was improved by antibiotic treatment, he underwent reoperation of the right modified Blalock-Taussig shunt using 8 mm knitted Dacron graft. Postoperative course was uneventful and dyspnea and cyanosys were improved. We successfully treated a complicated case of an adult congenital heart disease by reoperation of the right modified Blalock-Taussig shunt.     

Single-stage repair of tetralogy of Fallot with pseudoaneurysm: a unique approach

Pseudoaneurysm is a potentially lethal complication after modified Blalock-Taussig shunt. This report describes a frequently misdiagnosed clinical presentation along with noninvasive diagnosis of pseudoaneurysm after a modified Blalock-Taussig shunt. We report a novel single-stage surgical management of the pseudoaneurysm with concomitant complete repair of tetralogy of Fallot.     

Dilatable banding of a Blalock-Taussig shunt

Dilatable banding has been used in various situations. Sometimes Blalock-Taussig shunt banding is performed to prevent pulmonary overcirculation. Recently several reports have described dilatable pulmonary artery banding. We modified these methods for flow control of a Blalock-Taussig shunt. We report the case of a neonate with truncus arteriosus in which this technique was used.     

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.     

A rare association of tetralogy of Fallot and hypertrophic cardiomyopathy

Tetralogy of Fallot (TOF) is the most common form of cyanotic congenital heart disease. It is often associated with other congenital cardiac or non-cardiac defects. However, its association with hypertrophic cardiomyopathy (HCM) is rarely reported. We reported two cases. The first case is a full-term girl receiving modified Blalock-Taussig shunt creation and the second case is an 8-month old boy receiving total correction for TOF. Although they tolerated the operation well, both of them developed congestive heart failure and died of malignant cardiac arrhythmia several months after the operation. We made a literature review and only 11 case reports were found. There is currently no treatment guideline for this group of patients. From our limited experience and case reports, the physiology of HCM and TOF should both be taken into consideration when managing these patients. Close echocardiography follow-up with early myectomy and preventive implantation of implantable cardioverter-defibrillator may be beneficial for them.     

Acute pulmonary edema after Blalock-Taussig anastomosis.

Acute pulmonary edema developed in 2 patients after a Blalock-Taussig shunt procedure. Both patients had a univentricular heart complex with pulmonary stenosis. One patient underwent a modified Blalock-Taussig shunt using a polytetrafluoroethylene tube and the other underwent a classic Blalock-Taussig anastomosis. Acute pulmonary edema after the Blalock-Taussig shunt is rare, but once it has occurred, immediate treatment is obligatory.     

Surgical strategy for pulmonary coarctation in the univentricular heart.

OBJECTIVE: The placement of a modified Blalock-Taussig shunt in patients suffering from pulmonary coarctation can result in the aggravation of uneven pulmonary blood flow. This may subsequently obviate the possibility of future performance of the Fontan procedure. The objective of this study was to evaluate mid-term results in patients with pulmonary coarctation who had undergone the placement of a modified Blalock-Taussig shunt, coupled with a pulmonary artery angioplasty. METHODS: We retrospectively reviewed the records of 13 patients who had undergone the placement of a modified Blalock-Taussig shunt, coupled with concomitant pulmonary angioplasty, between September 1998 and August 2002. All patients received follow-up angiographic evaluations. RESULTS: On the ipsilateral side of the modified Blalock-Taussig shunt, we observed a significant increase in the pulmonary artery index during a mean follow-up period of 11+/-5 months (preoperative 82+/-37 mm2/m2, follow-up 129+/-57, p=0.03). On the contralateral side, we also observed a significant increase in the pulmonary artery index (preoperative 90+/-56 mm2/m2, follow-up 137+/-56, p=0.047). There was one late death. During the follow-up period (mean 23+/-18 months), 10 patients received either a bidirectional or total cavopulmonary shunt and five of these patients underwent extracardiac Fontan operations. CONCLUSIONS: Our study demonstrated that the placement of a modified Blalock-Taussig shunt, with concomitant pulmonary artery angioplasty, constitutes a good initial surgical strategy in cases of univentricular heart with pulmonary coarctation.     

Systemic-pulmonary shunts in infants and children. Early and late results

From September, 1978, to January, 1983, 44 cyanotic infants and children underwent a systemic-pulmonary artery shunt for the treatment of reduced pulmonary blood flow. Age ranged from 18 hours to 4 years (mean age = 0.49 years). Weight ranged from 1.7 kg to 13.2 kg (mean weight = 4.9 kg). There were 12 classic Blalock-Taussig shunts, five central polytetrafluoroethylene shunts, six interposition modified Blalock-Taussig shunts, and 21 Great Ormond Street type of modified Blalock-Taussig shunts. No direct aorta-pulmonary artery anastomoses were performed. There was one postoperative death (1/44 = 2.3%) in a 1,700 gm neonate born with pulmonary atresia and intact ventricular septum (shunt patent). Four shunts required early revision: one thrombosed central shunt, a kinked patent interposition Blalock-Taussig shunt, a small but patent Blalock-Taussig shunt, and one excessive Great Ormond Street type of Blalock-Taussig shunt. Two late deaths were probably shunt-related: one Blalock-Taussig and one central. All four types of shunts provided good palliation, but the Great Ormond Street type of Blalock-Taussig shunt is our preferred shunt because of (1) low operative risk, (2) predictable patency (100% in our series), (3) lack of distortion of pulmonary arterial anatomy, and (4) technical ease of insertion as well as takedown.     

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.     

Classic Blalock-Taussig shunt in neonates

BACKGROUND: The choice of palliative procedure for neonates with congenital cyanotic heart defects remains controversial. Several reports have questioned whether the classic Blalock-Taussig shunt is adequate in neonates, because it shows a high rate of mortality and early shunt failure. The purpose of this study is to evaluate the early and late results of classic Blalock-Taussig shunt in neonates. METHODS: From December 1981 to December 1996, 31 neonates underwent a classic Blalock-Taussig shunt. Mean age at operation was 15.9 days (range, 2 to 28 days), and mean body weight was 3214 g (range, 2229 to 4468 g). The major diagnoses were pulmonary atresia with intact ventricular septum (6 patients) and with ventricular septal defect (4), univentricular heart (6), tricuspid atresia (5), tetralogy of Fallot (4), transposition of the great arteries (3), and double outlet right ventricle (3). RESULTS: There were no early deaths. There was one early shunt failure. The patient underwent a replacement of Blalock-Taussig shunt by vascular graft on the 1st postoperative day. Two patients with non-confluent central pulmonary artery underwent a contralateral modified Blalock-Taussig shunt on the 22nd and 42nd postoperative day, respectively. There were two late deaths before the definitive repair was performed. Twelve patients required an additional shunt operation. The mean interval between the initial and the second shunt procedure was 27.7 months (range, 6 to 67 months). Ten patients underwent definitive operation and the mean interval to that procedure was 55.5 months (range, 14 to 121 months). Shunt patency was 94.7+/-5.1% at 3 years. The freedom from cardiac event (cardiac deaths or repeat shunting procedure) was 80.5+/-7.1% at 1 year and 54.9+/-9.4% at 3 years. CONCLUSIONS: The classic Blalock-Taussig shunt has a low operative mortality and has provided excellent long-term palliation in the neonate. We conclude that a classic Blalock-Taussig shunt should be considered a reasonable choice in neonates requiring a palliative procedure for congenital cyanotic heart defects.     

False aneurysm formation: a complication following the modified Blalock-Taussig shunt

False aneurysm formation is a rare complication of the modified Blalock-Taussig shunt. A patient is described in whom this complication arose 11 months after operation. Death resulted from rupture of the aneurysm into the right lung with associated massive hemoptysis. The onset of hemoptysis in patients with a functioning modified Blalock-Taussig shunt may be the first evidence of a developing false aneurysm.     

Growth of the pulmonary arteries after systemic-pulmonary shunt.

Pulmonary artery growth after a systemic-pulmonary shunt was angiographically evaluated in 19 out of 35 patients. The mean age of the subjects at the time of the initial operation was 18+/-18 months including 12 patients under a year old. The preoperative diagnosis was tetralogy of Fallot (TOF) in 10 patients, TOF plus pulmonary atresia in five and transposition of great arteries in four. A Blalock-Taussig shunt (BTS) operation was performed in 16 patients (15 classical and 1 modified) and a central shunt was performed in three patients as an initial operation. The preoperative pulmonary artery index (PAI) was 129+/-42 in all patients and there were no significant differences between patients under or over a year old (139+/-42 vs. 115+/-49). Postoperative angiography was performed 32+/-13 months after the surgery. Room air arterial O2 pressure increased significantly from 29+/-5 mmHg to 42+/-5 mmHg just after an initial palliative shunt operation. PAI change in patients under a year old was 214+/-73%, which was higher than 145+/-27% in patients over a year old after a palliative shunt operation. On the ipsilateral side, PAI change was almost the same between patients under and over a year old. On the contralateral side, PAI change in patients under a year old was 216+/-68%, which was significantly higher than the 116+/-21% in patients over one year old. There was a significant negative correlation (r=-0.65, p<0.05) between PAI change and arterial O2 pressure as measured just after a palliative shunt operation. In conclusion, a palliative shunt operation prior to a year old is desirable in order to produce sufficient and bilateral pulmonary artery growth.     

姑息手术在肺动脉闭锁合并室间隔缺损分期矫治中的应用

目的 总结改良Blalock-Taussig shunt(B-T分流术)、Waterston分流术和右心室肺动脉连接重建术3种不同姑息手术在肺动脉闭锁合并室间隔缺损((pulmonary atresia with ventricular septal defect,PAVSD)中的应用效果.方法 回顾性分析北京阜外心血...     

The evaluation of the modified Blalock-Taussig shunt with a prosthesis of microknitted Dacron for tetralogy of Fallot in early infancy]

We evaluated the surgical results of the modified Blalock-Taussig shunt (MBTS), performed with a prosthesis of microknitted Dacron, for the ductus-dependent tetralogy of Fallot (TOF) in early infancy. Nine MBTSs for eight patients, 4 with and 4 without pulmonary atresia, were performed, and one patient died. The mean age was 30 +/- 27 days, and the mean weight was 3460 +/- 770 g at the initial MBTS. In the initial two cases, the patients experienced convulsions due to severe hypoxia on account of the troubles of the preoperative administration of Prostaglandin E1 (PGE1). Thereafter, in order to prevent brain damage, we performed the MBTS following short-term administration of PGE1 (2-13 days). Consequently, we did not experience brain damage in later cases. Half of the patients with the MBTS with a 5 mm diameter prosthesis experienced postoperative congestive heart failure due to excessive pulmonary flow, and one of them died. The patients with the MBTS with a 4 mm diameter prosthesis had good postoperative courses. The suitable shunt flow in these patients was estimated to be 70-90 ml/kg/min. The MBTS with a 4 mm prosthesis obtained the lower level of this suitable shunt flow, but that a 5 mm prosthesis induced excessive shunt flow. Observing the patients' weight gain and the progress of polycythemia until two years of age, there were no differences between the MBTS with a 4 mm prosthesis and that with a 5 mm prosthesis. From these results, we recommend a 4 mm microknitted Dacron prosthesis for the MBTS of the TOF in early infancy.(ABSTRACT TRUNCATED AT 250 WORDS)     

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.     

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.     

Palliation of tetralogy of fallot by balloon dilation: Efficacy and safety

Seventeen patients with tetralogy of Fallot (TOF) were palliated by balloon dilation of the right ventricular outflow tract (RVOT). Their mean age was 9.8 months and mean weight 6.7 kg. Nine had hypercyanotic spells and eight had worsening cyanosis and polycythaemia. Successful dilation was achieved in 16 patients. The mean pulmonary valve annulus diameter measured angiographically was 8.8 mm and the mean balloon/annulus ratio was 1.5. Aortic oxygen saturation increased from mean (±SD) of 79(12)% before to 90(7)%. Pulmonary artery saturation rose from 64(12)% to 80(6)%. The systolic pressure gradient across the RVOT fell from 72.7(18.6) to 59.7(20.4) mmHg. One patient had a cardiac arrest prior to dilation and died shortly after the procedure. Four patients had cyanotic spells on induction of anaesthetic and one during the procedure. One patient had infundibular perforation by guide wire without any adverse sequelae and a Blalock-Taussig (BT) shunt was performed electively. Follow-up has ranged from 6–19 months with adequate palliation in all but five requiring a second procedure and one subsequently a third. Seven have undergone surgical correction and two patients unsuitable for correction had a BT shunt. In conclusion, balloon dilation of RVOT offers adequate palliation prior to surgery.     

Pulmonary atresia with intact ventricular septum: is neonatal repair advisable?

The optimal management of pulmonary atresia with an intact ventricular septum in the neonate remains controversial. The introduction of balloon septostomy and prostaglandin has significantly reduced early mortality but early surgical intervention is necessary to obtain a more adequate pulmonary blood flow. Fourteen neonates with pulmonary atresia and an intact ventricular septum were admitted to the Wessex Cardiothoracic Unit, Southampton from 1979 to 1986. Thirteen patients underwent cardiac catheterization. Cardiac catheterization data and right ventricular angiograms were reviewed retrospectively. Four patients with tripartite ventricles underwent total repair. The others received various palliative operations (valvotomy + modified Blalock-Taussig shunt or modified Blalock-Taussig shunt alone). Retrospective analysis of the angiograms indicated that right ventricular morphology alone is not a satisfactory criterion for surgical management. We have been able to demonstrate that there is a good correlation between the diameter of the tricuspid valve and the diameter of the infundibulum and that successful neonatal repair is possible when the tricuspid valve diameter is above 80% of the normal value for weight and when the tricuspid valve diameter to infundibular diameter ratio (TV/Inf ratio) is 2.2 or less. In patients with a tripartite ventricle but inadequate TV diameter and TV/Inf ratio, a closed pulmonary valvotomy with a modified Blalock-Taussig shunt remains the treatment of choice.