Clinical evaluation of the new Amplatzer duct occluder II for patent arterial duct occlusion.

BACKGROUND: Several devices such as coils and Amplatzer duct occluder (ADO) are used for catheter closure of patent arterial ducts (PDA). These carry a high success rate but residual shunts, suboptimal device orientation, and technical problems are encountered. The Amplatzer duct occluder II (ADO II) is designed to address these limitations. OBJECTIVES: To evaluate the technical features of the new ADO II device for PDA closure and document the immediate/early closure rate, complications and device behavior during implantation. METHODS: Prospective, two center study from February 2008 to January 2009. Twenty-seven patients (18 females) received the ADO II. The median age was 22 months (range: 7 months-68 years) and the median weight was 11.7 kg (range: 6.9-108). The median PDA diameter was 2.6 mm (range: 1-4.4). The approach was arterial in 13 and venous in 14 patients. Follow-up included echocardiography at 1 day and 1 month postimplantation. RESULTS: All implantations were technically successful with immediate complete angiographic closure in 21 and trivial contrast flow in six patients. The median procedure time was 43 min (range: 15-82) and the fluoroscopy time was 6 min (range: 2.2-26.5). Echocardiography confirmed no residual shunts on the following day. There were no complications. CONCLUSION: The new ADO II is a versatile and very effective device for closure of PDAs of various shapes, lengths, and up to diameters of 5.5 mm. The disc articulations, high early closure rate, arterial or venous approach options, and small diameter delivery catheter are all beneficial features.

Percutaneous transcatheter communication between the pulmonary artery and atrium following an extra-cardiac Fontan: an alternative approach to fenestration avoiding conduit perforation.

In a nonfenestrated modified Fontan, transcatheter creation of a fenestration presents technical difficulties, especially with the extra-cardiac modification where a Gore-Tex tube is placed between the inferior caval vein and the pulmonary arteries. The authors describe an alternative approach to perforating the Gore-Tex tube to create a fenestration by making a communication between the pulmonary artery and the atrial chamber, thus bridging the two circulations through native tissue.

Univentricular heart with systemic outflow obstruction: palliation by primary Damus procedure.

In 24 consecutive infants (19 male and 5 female) with complex forms of single-ventricle physiology and systemic outflow obstruction, a modified Damus operation without the use of exogenous material was undertaken in conjunction with creation of an aortopulmonary shunt 3.5 mm in diameter. The median age at operation was 6 days (range, 1 to 170 days) and the median weight, 3.4 kg (range, 2.6 to 4.6 kg). There were nine early deaths. All 15 survivors (median follow-up, 6.5 months) were clinically well without major systemic ventricular dysfunction or atrioventricular or arterial valve regurgitation. Ten of them have undergone a superior vena cava-pulmonary shunt (one death), and 1 has required patch angioplasty of the aortic arch and innominate artery with revision of the aortopulmonary shunt. The 4 other survivors are awaiting a cavopulmonary shunt. Univariate analysis yielded the chronologic rank for an individual procedure (higher risk of death early in the series), presence of aortic arch atresia, and presence or absence of transposition of the great arteries as predictors of death. This aggressive surgical approach provides excellent early palliation, and because the operation prevents abnormal ventricular hypertrophy from pressure or volume overload, systemic ventricular function is optimally conserved for a future Fontan-type procedure.

Endocarditis with multiple intracardiac shunts: identification and repair.

An 8-year-old boy who suffered from Hirschsprung's disease had development of tricuspid valve endocarditis that progressed to aortic root abscess formation, development of a fistulous communication between aorta and right atrium, atrial and ventricular septal defects, and a left ventricle to right atrium defect. Several surgical procedures were required. Operation consisted initially of closure of the septal defects and aortic valve repair. This was followed by homograft replacement of the aortic valve for persistent infection, and further closure of a left ventricle to right atrium fistula.

Occlusion of persistent left superior vena cava to unroofed coronary sinus using vena cava filter and coils.

A 48 year old female with complex cyanotic heart disease and pulmonary hypertension was partly cyanosed because of a persistent left superior vena cava draining into an unroofed coronary sinus. The left superior vena cava, which measured 22 mm in diameter, was successfully occluded with a Günther Tulip Vena Cava Mreye Filter which acted as a barrier for embolisation coils.

Adenosine induced transient cardiac standstill in catheter interventional procedures for congenital heart disease.

OBJECTIVE: To describe the use of intravenous adenosine to create transient cardiac standstill during balloon dilatation procedures for congenital heart defects. SETTING: A tertiary paediatric cardiac centre. DESIGN AND PATIENTS: This was a prospective pilot study. Thirteen patients born with congenital heart disease and who had stenotic lesions requiring relief were considered for the technique. All were suitable for balloon dilatation. Their ages ranged from 2 months to 30 years, mean (SD) 9.9 (9.8) years. The dose of adenosine varied from 0.125 mg/kg to 0.555 mg/kg, mean 0.33 (0.127). RESULTS: Two patients only developed sinus bradycardia in response to adenosine, which may have been related to the technique of administration. The other 11 experienced a period of asystole, which ranged from 2.4 to 10.8 seconds, mean 4.99 (2.27), and a total atrioventricular block period of 5.0 to 21.2 seconds, mean 9.47 (4.64). The interval between adenosine injection and the onset of asystole varied from 2.4 to 15.8 seconds, mean 8.05 (3.6), depending on cannula size, site of administration, and cardiac output. The peak gradient across the stenotic lesions fell from 52.3 (23.7) to 17.8 (11.9) mm Hg (p < 0.001). Apart from one short episode of atrial fibrillation there were no complications. CONCLUSIONS: Intravenous adenosine is a safe and effective agent for creating transient cardiac standstill during balloon dilatation procedures for congenital heart disease. This achieves stability which is likely to improve results and reduce complications. It may have applications in other fields of cardiac intervention where an immobile heart is desirable during the critical phase of a procedure.

Recovery pattern of left ventricular dysfunction following radiofrequency ablation of incessant supraventricular tachycardia in infants and children.

OBJECTIVE: To assess recovery pattern of left ventricular function secondary to incessant tachycardia after radiofrequency ablation in a group of infants and children. DESIGN AND SETTING: A combined prospective and retrospective echocardiographic study carried out in a tertiary paediatric cardiac centre. PATIENTS: Echocardiographic evaluation of left ventricular size and function in nine children with incessant tachycardia, before and after successful radiofrequency ablation. Age at ablation ranged from 2 months to 12.5 years (mean 4.1 years). Recovery of left ventricular function was analysed in relation to age at ablation (group I < 18 months, group II > 18 months). MAIN OUTCOME MEASURE: Ventricular recovery pattern. RESULTS: Seven of the nine children had left ventricular dysfunction; six of these also had left ventricular dilatation. All children with left ventricular dysfunction had normalisation of ejection fraction and fractional shortening; left ventricular dilatation also improved, but the improvement occurred after recovery of function. There was a shorter recovery time for left ventricular function in younger (group I) than in older children (group II) (mean (SD) 5.7 (7.2) months v 31.3 (5.2) (p < 0.002). CONCLUSIONS: Tachycardia induced cardiomyopathy is reversible following curative treatment with radiofrequency. Recovery of left ventricular systolic function precedes recovery of left ventricular dilatation. Time course to recovery is shorter in younger children.

Management and outcome of infants and children with right atrial isomerism.

OBJECTIVES: To assess the current results and outcome of surgery in infants and children with right atrial isomerism and complex congenital heart disease. SETTING: Tertiary referral centre. METHODS: 20 consecutive children with right atrial isomerism and complex congenital heart disease underwent surgery over a 6 year period between August 1987 and July 1993. The results and outcome were analysed according to age, presentation, and surgical procedures. RESULTS: Patients were divided into two groups depending on age at presentation and initial surgery: group A comprised 11 patients who required surgical intervention in the first month of life (mean age 5 days); and group B comprised nine patients who required initial surgical intervention after the first month of life (mean age 6.8 months). Seven (64%) of the 11 patients in group A had obstructed pulmonary venous drainage and ten (91%) had pulmonary atresia. There were seven early deaths (64%), including the five patients who required systemic to pulmonary artery shunt and simultaneous repair of obstructed pulmonary veins. The long-term survival rate in this group was 18% (two of 11). Pulmonary venous obstruction was present in two (22%) of the nine patients in group B and four (44%) had pulmonary atresia. There were no early deaths. One patient died after a second palliative procedure. There was one late sudden death. Four patients had a Fontan operation with no deaths. Two of the remaining three patients meet the Fontan criteria. The long-term survival rate in this group was 78% (seven of nine). CONCLUSIONS: Surgical management of patients with right atrial isomerism who have complex congenital heart disease carries a high mortality and remains palliative. The overall survival rate was 45% (nine of 20); 18% in patients requiring surgery in the first month of life (group A) and 78% in patients requiring surgery after the first month of life (group B) (P < 0.001). Of the total of 20 patients, nine were potential candidates for a Fontan operation. Seven of these have undergone a Fontan procedure with five survivors.

Echocardiographic screening in neonates undergoing surgery for selected gastrointestinal malformations.

To compare echocardiography with clinical examination, radiography, and electrocardiography for the detection of congenital heart defects (CHD) a four year prospective study was carried out in 166 neonates with selected congenital gastrointestinal malformations (anorectal anomaly, tracheo-oesophageal fistula, duodenal atresia, exomphalos, and gastroschisis). Routine examination and investigation detected CHD in 16 neonates. Using echocardiography CHD was diagnosed in 38 (23%) neonates of whom five had two gastrointestinal malformations: in 22/57 (39%) with a tracheo-oesophageal fistula, 10/67 (15%) with an anorectal anomaly, 4/20 (20%) with exomphalos, 6/20 (30%) with duodenal atresia, and 1/7 with gastroschisis. A significantly higher incidence of CHD in neonates with gastrointestinal malformations was diagnosed using echocardiography (23%) compared with routine examination and investigation (9%). Early diagnosis of CHD allowed a unified approach to be presented to the family.

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 less than 0.01). In small children, CPA avoids the complications of SPAS and, in some patients, may itself achieve adequate long-term definitive palliation.

Complete atrioventricular septal defects: the influence of associated cardiac anomalies on surgical management and outcome.

OBJECTIVE: Major associated cardiac anomalies are known to increase the risk of repair of complete atrioventricular septal defects (CAVSDs). The purpose of this study was to examine the effects of such anomalies on the current surgical management of CAVSDs and their influence on outcome following repair. METHODS: We performed a retrospective review of a 100 consecutive non-isomeric patients undergoing repair of CAVSD at our institution, between January 1989 and December 1994; patients with partial or intermediate defects were excluded. Complete atrioventricular septal defect patients with other major cardiac abnormalities (complex) were then compared to those with isolated CAVSDs. RESULTS: There were 15 patients (15%) with associated anomalies; 3 had tetralogy of Fallot, 1 patient had pulmonary atresia, 6 had hypoplastic left or right ventricle, 1 had tetralogy of Fallot and hyperplastic right ventricle, 2 patients had double outlet right ventricle, 1 had hypoplastic aortic arch and 1 patient had aortic coarctation. The median age at operation was similar for both groups (4.2 months), while the median weight was not significantly different for isolated CAVSDs compared to complex (4.2 months vs 3.4 months, P = 0.89), but there was a higher incidence of trisomy 21 (70/85, 82% vs 8/15, 53.3%, P = 0.01). Two of the 85 isolated CAVSD patients (2.3%) had undergone palliative pulmonary artery banding, while 5 of the 15 complex patients (33.3%) had either banding or Blalock-Taussig shunts performed. The technique of CAVSD repair was identical in each group. All complex patients had standard repair of their associated anomalies. Hospital mortality was higher in the complex group (3/15, 20% vs 2/85, 2.3%, P = 0.004); all early deaths in the complex group occurred in patients with a hypoplastic ventricle. Reoperation for left atrioventricular valve regurgitation was required in six isolated CAVSD patients (7.1%) and in one complex (6.6%). CONCLUSIONS: In the absence of significant ventricular hypoplasia, the early results of surgical repair in patients with CAVSDs and associated cardiovascular anomalies are similar to those achieved in patients with isolated CAVSD.

Total anomalous pulmonary venous connection: outcome of surgical correction and management of recurrent venous obstruction.

OBJECTIVE: Total anomalous pulmonary venous connection (TAPVC) can be corrected with low mortality and good outcome. If complicated by pulmonary vein stenosis (PVS), either at presentation or secondary to the repair, the long-term outcome is compromised. We have evaluated an institutional experience with TAPVC, with particular regard to the evolving management of PVS. METHODS: Retrospective analysis of 85 consecutive patients with non-isomeric TAPVC undergoing surgical correction over a 10-year period (1988-1997). In addition, three patients were referred to us with secondary PVS, having had their primary procedure elsewhere. Attention was focused on incidence of PVS, and strategies for management. RESULTS: Median age at first operation was 33 days (range 1-533). Site of drainage was supracardiac (43/88), infracardiac (20/88), cardiac (17/88), and mixed (8/88). On presentation, 35% of patients were ventilated. Early mortality was 7% (6/85), with one late non-cardiac death. 82% of the original patients (70/85) are currently well at a median follow-up of 64 months (range 6-119). The incidence of PVS requiring intervention was 11% (9/85). Median time to PVS was 41 days. In these patients, 18 balloon angioplasties, four endovascular stent placements (in two patients), and a further 23 surgical procedures were performed. Of the nine patients undergoing re-intervention after initial surgery at our institution, five (56%) survived. Two of these have no residual obstruction and right ventricular pressure (RVP) < 50% systemic, two have unilateral obstruction and RVP < 50% systemic, and one has bilateral obstruction and RVP 80% systemic. Of the three patients referred to us with secondary PVS, two are alive and well, and one died early after the first re-operation. CONCLUSIONS: Intrinsic obstruction (endocardial sclerosis or thickening) is associated with worse prognosis and earlier re-intervention than extrinsic (anatomical) obstruction. We advocate an early, aggressive approach to the management of patients with TAPVC, especially in the presence of PVS. This complication is most appropriately managed by a combination of re-operation and repeated balloon dilation.

Early results of right ventricular-pulmonary artery conduits in patients under 1 year of age.

OBJECTIVES: Management strategies for the repair of many complex heart defects require the implantation of a valved conduit between the right ventricle (RV) and the pulmonary artery (PA), often using aortic or pulmonary homograft valves. Their limited availability, however, has led to the development and use of new conduits. We retrospectively compared our experience with small homografts in patients of less than 1 year of age with the TissueMed bioprosthetic valved conduit. METHODS: From March 1994 to November 1997 29 patients in their first year of life underwent conduit implantation for complex heart defects. These were retrospectively reviewed in order to determine the incidence of death or conduit stenosis. Seventeen patients received homografts and 12 TissueMed conduits. RESULTS: Diagnoses and operative details including conduit size were similar in the two groups and in all cases complete repair of the underlying defect was carried out. Early post-operative mortality was 4/17 (23.5%) in the homograft group and 3/12 (25%) in the TissueMed group. Echo Doppler evaluation within 1 month of operation showed no right ventricular outflow tract (RVOT) obstruction in any of the survivors. In the TissueMed group 8/9 (77%) survivors have gone on to develop significant RVOT obstruction within 12 months of operation. There have been three late deaths in this group all related to severe RVOT obstruction. Two patients died during an attempt at balloon dilatation and one patient died of progressive right heart failure. Five patients had successful replacement of the TissueMed conduit. One child remains well with no evidence of RVOT obstruction. At operation to replace conduit, or at autopsy, the stenoses were related to the deposition of fibrous tissue at the anastomotic suture lines. In the homograft group none of the survivors developed RVOT obstruction during the first 12 months post-operatively. There was one late death (non-cardiac in origin) and one child is awaiting conduit replacement 40 months after initial implantation for obstruction. CONCLUSIONS: The homograft is a satisfactory conduit for re-establishment of RV-PA continuity in infancy. Further work needs to be undertaken in order to elucidate the mechanisms of early graft failure in bioprosthetic conduits if these are to be a suitable alternative for RV outflow reconstruction in infants.

Management of cor triatriatum dexter by balloon dilatation in three dogs.

Two dogs, one immature and one adult, were presented with a history of progressive ascites. In a third, immature dog, increasing exercise intolerance had been noted. Echocardiography demonstrated a partition in the right atrium (cor triatriatum dexter) and echocontrast studies documented normal flow from the cranial vena cava into the right atrium and ventricle. A saphenous vein contrast study demonstrated flow from the caudal vena cava into an accessory right atrial chamber (sinus venarum). The sinus venarum communicated with the true right atrium via a small defect in the atrial membrane in one dog, and additionally with the left atrium via a right-to-left shunting foramen ovale in the other dogs. All defects were visualised on angiographic studies by selective catheterisation of the caudal vena cava via the femoral vein. Balloon dilatation of the defect was then performed using a small followed by a larger balloon angioplasty catheter to enlarge the defect in the atrial membrane. Clinical signs improved within days and were sustained in the long-term in all cases.

Staged surgical management of hypoplastic left heart syndrome: a single institution 12 year experience.

OBJECTIVE: To describe a 12 year experience with staged surgical management of the hypoplastic left heart syndrome (HLHS) and to identify the factors that influenced outcome. METHODS: Between December 1992 and June 2004, 333 patients with HLHS underwent a Norwood procedure (median age 4 days, range 0-217 days). Subsequently 203 patients underwent a bidirectional Glenn procedure (stage II) and 81 patients underwent a modified Fontan procedure (stage III). Follow up was complete (median interval 3.7 years, range 32 days to 11.3 years). RESULTS: Early mortality after the Norwood procedure was 29% (n = 95); this decreased from 46% (first year) to 16% (last year; p < 0.05). Between stages, 49 patients died, 27 before stage II and 22 between stages II and III. There were one early and three late deaths after stage III. Actuarial survival (SEM) was 58% (3%) at one year and 50% (3%) at five and 10 years. On multivariable analysis, five factors influenced early mortality after the Norwood procedure (p < 0.05). Pulmonary blood flow supplied by a right ventricle to pulmonary artery (RV-PA) conduit, arch reconstruction with pulmonary homograft patch, and increased operative weight improved early mortality. Increased periods of cardiopulmonary bypass and deep hypothermic circulatory arrest increased early mortality. Similar factors also influenced actuarial survival after the Norwood procedure. CONCLUSION: This study identified an improvement in outcome after staged surgical management of HLHS, which was primarily attributable to changes in surgical technique. The RV-PA conduit, in particular, was associated with a notable and independent improvement in early and actuarial survival.