Successful surgical management of infected modified Blalock-Taussig shunts

We describe the successful management of two patients with infected modified Blalock-Taussig shunts by replacement of the graft combined with antibiotic therapy.     

Absent pulmonary valve and origin of left pulmonary artery from ascending aorta

A rare combination of tetralogy of Fallot, absent pulmonary valve and absent left pulmonary artery is described. The clinical and angiographic profile and the impact on management are discussed. The embryology is outlined.     

Massive pulmonary valve insufficiency associated with double pulmonary artery and ascending aorta aneurysm

A case is reported of aneurysm of both the ascending aorta and pulmonary artery, associated with massive pulmonary valve insufficiency. Pulmonary artery aneurysm is a rare condition of unknown natural history; therapeutic management has not yet been established. Pulmonary valve insufficiency is also rare, with reported etiologies comprising mainly pulmonary valve anomalies. A comparative review of the literature relating to the diagnosis and therapeutic management of the condition is provided.     

Anomalous origin of one pulmonary artery from the ascending aorta

We describe the surgical repair in three infants presenting with one pulmonary artery arising from the ascending aorta, the other artery arising normally from the right ventricle via the pulmonary trunk. Repair consisted of reimplantation of the anomalous pulmonary artery to the pulmonary trunk, in association with repair of associated intracardiac malformations. All patients survived the surgical procedures, and were discharged in stable clinical condition. Subsequently, two of the three patients developed stenosis at the surgical anastomosis relatively early after the initial procedure, and underwent reoperation. Although survival after operation is now expected for this malformation, reports of late results are lacking. Larger numbers of operations are needed before we can reach definitive conclusions. The origin of one branch pulmonary artery from the ascending aorta in the presence of a pulmonary valve and main pulmonary artery is a very rare congenital cardiac anomaly. PATIENTS AND METHODS: Between January 1995 and June 2003, 3 infant girls presented with the origin of one branch artery from the ascending aorta, while the other pulmonary artery originated from the pulmonary trunk which was in continuity with the right ventricular outflow tract. The pulmonary artery that arose from the right ventricle was left in 2 and right in 1 patient. RESULTS: At the age 13, 48 and 62 days respectively, the patients underwent surgical repair consisting with reimplantation of the anomalous pulmonary artery branch to the pulmonary trunk in association with repair of intracardiac malformations. There were no hospital deaths. Postoperative complications included: prolonged intubation in two patients (10 and 16 days), low output syndrome in 1 patient, cardiac tamponade in 1 patient and seizures in 1 patient. All patients were discharged in good clinical condition. There have been no late deaths. Subsequently, two of the three patients developed stenosis at the surgical anastomosis relatively early after the initial procedure, and after unsuccessful balloon dilation, underwent surgical reoperation. CONCLUSIONS: Although operative survival is now possible for this malformation, reports of late results are lacking. Two of the three patients developed stenosis at the surgical anastomosis relatively early after surgery. Larger numbers of operations are necessaries to reach definitive conclusions.     

Magnetic resonance imaging: evaluation of the Blalock-Taussig shunts and anatomy of the pulmonary artery]

The morphology and circulation of the pulmonary arteries and shunt vessels were evaluated by magnetic resonance imaging (MRI) in 8 patients with cyanotic heart disease after a Blalock-Taussig shunt operation. Their ages ranged from one month to 17 years. MRI permitted assessment of the size and patency of the Blalock-Taussig shunts, as well as the size and morphology of the pulmonary arteries in all patients. Measurements of the vessel diameters on MRI correlated well with the angiographic measurements (main pulmonary artery, r = 0.98; right pulmonary artery, r = 0.98; left pulmonary artery, r = 0.98; and Blalock-Taussig shunt, r = 0.97). MRI successfully imaged 3 of 4 shunt obstructions and 3 of 4 pulmonary stenoses with high resolution. In assessing peripheral pulmonary stenosis or obstruction, MRI was superior to echocardiography, the latter being unable to image peripheral pulmonary arteries satisfactorily. We concluded that MRI is an excellent noninvasive method for serially evaluating the anatomy and function of Blalock-Taussig shunts and pulmonary arteries, which is particularly useful for children with cyanotic congenital heart disease.     

A simple method of treating seromas involving modified Blalock-Taussig shunts

We treated seromas developing in two patients in relation to left-sided modified Blalock-Taussig shunts by reattaching the original graft to the descending aorta. We postulate that seromas may develop because of the large area of contact between the graft and blood. Shortening the length of the Gore-Tex graft may therefore be a feasible treatment.     

Emergency transcatheter balloon recanalization of acutely thrombosed modified Blalock-Taussig shunts

BACKGROUND: Modified Blalock-Taussig shunts are used to palliate a variety of cyanotic heart diseases associated with reduced pulmonary blood flow. Acute shunt thrombosis in patients with shunt-dependent pulmonary blood flow can result in life-threatening hypoxia. We describe our experience of emergency transcatheter recanalization in 5 severely hypoxic children with acute shunt occlusion. METHODS AND RESULTS: Five patients with ages ranging between 5 and 24 months (median 11 months) and weight ranging from 4 to 8 kg (median 5 kg) presented with severe hypoxia, acidosis and hypotension following acute occlusion of modified Blalock-Taussig shunts placed 11 days to 12 months ago. As severe hypoxia (saturation range 3 5%-5 0%), acidosis and a state of shock in all the patients increased the risk for a redo surgical procedure, they were taken up for emergency transcatheter recanalization within 2-6 hours of hospitalization. This was done by positioning a Judkin's right coronary catheter at the mouth of the thrombosed shunt, crossing the shunt with a guidewire and serial dilatations with coronary and/or peripheral angioplasty balloons to the size of the graft. This technique was immediately successful in 4 of the 5 patients, thereby avoiding a repeat palliative operation. In 2 patients with residual stenosis, stents were used to restore luminal patency. One patient with acute stent thrombosis was managed successfully with local delivery of thrombolysis for 36 hours, which resulted in good luminal patency. At follow-up after 6 and 12 months, the shunts in both the stented patients are patent, with an oxygen saturation of 78% and 80%, respectively. In 2 other patients who had undergone plain balloon angioplasty, the shunts remained patent for 11 days (died of bronchopneumonia and septicemia) and 3 months, respectively. The procedure was unsuccessful in one very sick patient in whom the shunt had a tortuous course. CONCLUSIONS: Transcatheter recanalization of an acutely thrombosed Blalock-Taussig shunt is feasible. It can offer satisfactory short-term palliation in selected patients. Stents may play a role in patients with residual narrowing after dilatation. The procedure can be expeditiously accomplished in an emergency situation in a severely hypoxic child and may be a realistic alternative to surgery or thrombolysis.     

Balloon occlusion of the carotid artery for the angiographic visualization of Blalock-Taussig shunts and pulmonary arteries

We describe the use of a balloon catheter to occlude the right or left carotid artery as a way of directing contrast material to the pulmonary arteries. This procedure was carried out in the postoperative study of 14 children who had undergone a Blalock-Taussig shunt. The method was reliable, and the angiograms provided excellent visualization of the pulmonary arteries using only small volumes of contrast material.     

Balloon angioplasty for obstructed modified systemic-pulmonary artery shunts and pulmonary artery stenoses.

OBJECTIVES: The results of percutaneous balloon angioplasty for obstructed modified Blalock-Taussig (BT) or central shunts and pulmonary artery (PA) stenoses were studied to assess its role as an alternative to second shunt and surgical PA angioplasty. BACKGROUND: Obstruction of a modified shunt and PA stenosis related to the shunt or ductus are not infrequent. A second shunt with or without PA angioplastv is required if the PA size, morphology or age of the patient is suboptimal for definitive surgery. METHODS: From June 1994 to May 1999, balloon angioplasty for obstructed systemic-to-PA shunts was performed in 46 patients, with ages ranging from 1 month to 7.4 years (2.2 +/- 1.9 years). Among the 46 patients, 32 had modified BT shunts, 5 had bilateral shunts, 7 had modified central shunts, and 2 had both modified BT and central shunts. Stenoses were seen in 27 main branch PAs, and interruption was present in three. A concurrent balloon angioplasty was attempted in 28 main branch PAs, but it was performed in only 25 vessels. RESULTS: Balloon dilation for obstructed modified shunts was considered to be effective in 42 patients (91%), while angioplasty for PA stenosis was effective in 14 vessels and not effective in 11 vessels. After balloon dilation angioplastv, oxygen saturation in the aorta increased from 74.4 +/- 4.3% to 80.8 +/- 3.6% (p < 0.01) in these 46 patients. One patient died of pneumonia. Eight patients required an additional modified BT shunt soon after the procedure because of severe stenosis or interruption at main branch PA. After a mean follow-up period of 11.6 +/- 5.4 months, 29 patients underwent a repeated imaging study to evaluate the morphology and size of the PAs. Of these 29 patients, 26 underwent open-heart surgery, with two mortalities. CONCLUSIONS: When a second shunt is under consideration because of obstruction of the modified shunt, balloon angioplasty is a possible alternative procedure. Pulmonary artery stenosis, if present, can be simultaneously dilated.     

Long-term positive remodeling of the right coronary artery after reimplantation from the pulmonary artery to the ascending aorta

A 53-year-old woman, nonsmoking patient, with a history of surgically corrected anomalous origin of the right coronary artery from the pulmonary artery 17 years prior to admission, presented to our department complaining of mild, left-sided exertional chest pain for the past 3 months. She underwent a computed tomography examination of the heart and coronary angiography revealing postsurgical changes to the coronary vasculature and severe stenosis of the left circumflex artery, which was successfully treated by percutaneous stent implantation.     

Prediction of moderate or severe pulmonary hypertension by main pulmonary artery diameter and main pulmonary artery diameter/ascending aorta diameter in pulmonary embolism

We investigated the accuracy of computed tomographic measurements of main pulmonary artery diameter (MPAD) and of MPAD/ascending aorta diameter (AAD) in predicting moderate or severe pulmonary hypertension in 190 patients with acute pulmonary embolism. A pulmonary artery systolic pressure of > or = 50 mm Hg measured by Doppler echocardiography was considered moderate or severe pulmonary hypertension. A MPAD of > 28.6 mm and a MPAD/AAD ratio of > or = 1.00 measured by computed tomography were considered abnormal. A MPAD of > 28.6 mm had a 75% sensitivity and specificity, a 52% positive predictive value, a 89% negative predictive value, a 3.0 likelihood ratio for a positive test, and a 0.33 likelihood ratio for a negative test in predicting moderate or severe pulmonary hypertension. A MPAD/AAD ratio of > or = 1.00 had a 59% sensitivity, a 82% specificity, a 55% positive predictive value, a 84% negative predictive value, a 3.3 likelihood ratio for a positive test, and a 0.50 likelihood ratio for a negative test.     

Transcatheter closure of Blalock-Taussig shunts with a modified Rashkind umbrella delivery system.

Transcatheter occlusion of Blalock-Taussig shunts was successfully performed in three children with the Rashkind double umbrella occluding device. Complete occlusion was confirmed angiographically in two patients and echocardiographically in the third. The delivery system was adapted for use through smaller sheaths making it more suitable for small children or arterial access.