Blade consolidation of multiple atrial septal defects: a novel approach to transcatheter closure.

The Amplatzer atrial septal defect occlusion device has gained popularity for the nonoperative closure of secundum-type defects. We describe a case of multiple atrial septal defects that were "consolidated" into a single defect using blade atrial septostomy for successful closure with single Amplatzer device.

Cost-effectiveness of coarctation repair strategies: endovascular stenting versus surgery.

The cost-effectiveness of stent (ST) implantation for the repair of coarctation of the aorta (CoA) is not documented in the medical literature. Inflation-adjusted hospital costs for ST implantation and for surgical (SU) repair were obtained using the HBOC Cost Accounting System software and evaluated for all patients 5 years of age or older who underwent elective treatment of CoA between July 1997 and June 2001. The average age of the ST group (n = 10) to 9.5 +/- 3.5 years for the SU group (n = 12) (p > 0.10). The ST group had one failure due to inability to cross the CoA (failure rate, 10%). Successful repair was accomplished in all other ST cases and in all SU cases, with no residual systolic gradients at 1-year follow-up. Hospital length of stay for the ST group was 0.8 +/- 1.2 days compared to 3.5 +/- 0.5 days for the SU group (p < 0.001). The mean inflation-adjusted cost for the ST group was dollar 7,148 +/- 2,984 versus dollar 11,769 +/- 3,702 for the SU group (p < 0.005). By intention to treat analysis, the cost of repair in the ST-first group was dollar 8,325 +/- 3,354 given the 10% failure rate (p < 0.04 vs the SU only group). Sensitivity analysis demonstrates that cost of repair is lower with the ST-first strategy compared to SU only until the failure rate of ST implantation exceeds 39%. Repair of CoA using an endovascular stent strategy is cost-effective compared to conventional surgical repair.

Unrecognized pulmonary venous desaturation early after Norwood palliation confounds Gp:Gs assessment and compromises oxygen delivery.

BACKGROUND: Hemodynamic stability after Norwood palliation often requires manipulation of pulmonary vascular resistance to alter the pulmonary-to-systemic blood flow ratio (Qp:Qs). Qp:Qs is often estimated from arterial saturation (SaO2), a practice based on 2 untested assumptions: constant systemic arteriovenous O2 difference and normal pulmonary venous saturation. METHODS AND RESULTS: In 12 patients early (

Unique echocardiographic features associated with deployment of the Amplatzer atrial septal defect device.

The purpose of this study was to describe the unique echocardiographic findings associated with deployment of the Amplatzer atrial septal defect (ASD) device. Thirty-five patients (2 to 40 years old; 23 female and 12 male patients) underwent echocardiography during attempted ASD closure with the Amplatzer device. Transesophageal and transthoracic echocardiograms were performed during the placement and follow-up of the device, respectively. In 5 patients, the device was not deployed because of transesophageal echocardiography (TEE) findings (an exceedingly large defect in 3 patients, partial obstruction of the upper right pulmonary vein by the device in 1, and complex atrial septal anatomy in 1). In the remaining 30 patients, after deployment but before release, the device distorted the atrial septum from the normal vertical orientation to an oblique transverse orientation. Excessive septal distortion (i.e., > or =90 degrees in 1 patient) was associated with device embolization upon release. In other patients, TEE also identified mild splaying of the device on the aortic wall, mild abutment of the device upon the mitral valve, and temporary partial obstruction of pulmonary vein flow. Color Doppler revealed residual shunts in 21 of 29 patients immediately after release, but in none of 15 patients at 1-year follow-up. Transesophageal echocardiography is essential to ensure proper Amplatzer device placement. Distortion of the atrial septum and Amplatzer device orientation occur before release but resolve on release from the delivery cable. Small residual shunts are common early, but they resolve in 6 to 12 months.

One-year follow-up of the amplatzer device to close atrial septal defects.

The early and 1-year follow-up of a single United States center using the Amplatzer atrial septal defect closure device is reported. Complete closure was documented in all patients by 1 year after device implantation.

Exposure to ionizing radiation in children undergoing Amplatzer device placement to close atrial septal defects.

To evaluate exposure to ionizing radiation during Amplatzer device occlusion, a prospective study was performed to measure surface entrance radiation dose by thermoluminescent dosimetry (TLD). Between June 1998 and April 1999, dosimetry was carried out on 12 patients with Amplatzer device occlusion of atrial septal defects (n = 10) or Fontan fenestration (n =) and 12 age-matched patients who underwent diagnostic catherization. TLD chips were placed at the posterior (PA) and right lateral (LA) chest wall as well as the thyroid (TH) and gonadal (GN) regions. The Amplatzer group had a median age of 6.4 yr (2.4-12.4 yr) and a median weight of 23.7 kg (15.6-28.9 kg), which were similar (p = NS) to those of the control group, who had a median age of 7.9 yr (3.3-16.2 yr) and a median weight of 29.9 kg (10.6-58.0 kg). Device placement was successful in 11 of 12 patients; one device was removed owing to partial obstruction of the right-upper pulmonary vein. Fluoroscopy times were also similar in the Amplatzer group (23.5 +/- 2.1 min) and the control group (16.4 +/- 3.1 min; P = NS). The measured surface entrance doses of the Amplatzer group was similar (p = NS) to those of the control group in all four regions: PA (4.96 +/- 1.88 vs. 6.07 +/- 2.16 cGy), LA (5.22 +/- 1.68 vs. 3.13 +/- 1.25 cGy), TH (0.92 +/- 0.14 vs. 0.69 +/- 0.09 cGy), and GN (0.20 +/- 0.00 vs. 0.22 +/- 0.01cGy). Fluoroscopy times and measured surface entrance doses of ionizing radiation in patients undergoing Amplatzer device occlusion are similar to those in patients undergoing routine diagnostic catheterization.

Radiation exposure to children during coil occlusion of the patent ductus arteriosus.

The risks of excessive exposure to ionizing radiation are well described and measures are routinely taken to limit such exposure to both patient and personnel in the catheterization laboratory. Coll occlusion of the patent ductus arteriosus (PDA) as well as other more complex pediatric interventions has raised concern regarding radiation exposure, particularly as minimally invasive surgical techniques are being developed which lack such exposure risk. In eight consecutive patients, aged 0.7-7 years (median, 2.3 years), coil occlusion of a PDA was performed and surface entrance radiation dose determined by thermoluminescent dosimetry (TD). Total cumulative doses (PA + lateral dose) were also calculated for each patient. Entrance and cumulative dose was likewise measured in 12 patients undergoing standard diagnostic catheterization (DC) and in 5 consecutive patients undergoing pulmonary balloon valvuloplasty (PBV). The groups were comparable in age, weight, and body surface area (BSA). Total cumulative dose in the PDA patients was 97 +/- 25 mGy (mean +/- SE). There was no significant difference between the three groups in entrance dose absorbed at each location or in total cumulative dose. The mean total fluoroscopy time in the PDA occlusion group was significantly less than that of the PBV group (10.1 +/- 1.81 min vs. 19.3 +/- 2.29 min, P < 0.05) but was comparable to the DC group (13.2 +/- 1.5 min, P = NS). When the subjects were analyzed collectively, no correlation between fluoroscopy time and measured entrance dose was observed. The strongest correlates of total cumulative dose were patient weight (r = 0.67, P < 0.001) and BSA (r = 0.62, P = 0.001). Patients undergoing coil occlusion of a PDA are not exposed to increased radiation entrance dose compared to those undergoing standard DC and PBV. Furthermore, surface entrance radiation dose as determined by TD varies according to patient size for a given fluoroscopy time.

Transhepatic therapeutic cardiac catheterization: a new option for the pediatric interventionalist.

We evaluate the efficacy and safety of percutaneous transhepatic (TH) venous access for interventional cardiac catheterization. A retrospective review of all TH therapeutic catheterizations between January 1994 and September 1998 was performed. Patient demographics, pre- and postcatheterization hemoglobin and liver function studies, and complications were evaluated. TH access was performed for 30 interventional catheterizations in 25 patients with a median age of 39 months (range, 1 day to 41 years) and weight of 13.2 kg (3.1-87.0 kg). Indications for TH access were bilateral obstructed femoral veins (n = 15), obstructed femoral veins and superior vena cava (n = 3), Greenfield filter (n = 2), and presumptive improved route for intervention via TH access (n = 5). TH interventions were successful in 29/30 procedures (97%). Interventions via TH sheath sizes of 4-14 Fr included pulmonary angioplasty +/- stent (n = 11), radiofrequency ablation (n = 4), atrial septal defect device occlusion (n = 2), coil occlusion of pulmonary artery pseduoaneurysm (n = 2), Fontan fenestration device occlusion (n = 2), pulmonary valvuloplasty (n = 2), stent dilation of the superior vena cava (n = 2), and one each of device retrieval, Fontan baffle stent placement and subsequent redilation, Fontan fenestration dilation, transseptal mitral valvuloplasty, and cardiac biopsy. There were no changes in pre- and post-TH hemoglobin levels (mean +/- SD, 12.9+/-2.2 vs. 11.9+/-1.9 gm/dL; P = NS) or alanine transferase (34.0+/-27.5 vs. 43.4+/-18.2 IU/L; P = NS). One patient developed important intraperitoneal bleeding and required exploratory laporatomy. Percutaneous TH access is safe and effective as a route for interventional catheter procedures for patients with limited venous access.

Utility of cardiac catheterization in pediatric cardiac patients on ECMO.

Cardiac catheterization has been utilized rarely in children on extracorporeal membrane oxygenation (ECMO). We performed a retrospective review of 15 children with congenital heart disease who had undergone catheterization while on ECMO from December 1990-December 1995. The procedures, including four interventions, were successful in all patients with adequate evaluation of clinical questions. Unexpected diagnostic information of clinical importance was obtained in 40%, and clinical management of patients was significantly altered in 73%. All patients tolerated the procedure and transport well. The only significant complication was a retroperitoneal hemorrhage in one patient after approximately 12 hr. Although no patients died at catheterization, overall survival was poor, with 50% weaning from ECMO, 29% surviving to discharge, and 14% surviving at follow-up. We conclude that diagnostic and interventional catheterization may be performed in patients on ECMO with acceptable morbidity and mortality; however, long-term survival in this population is poor.

Thrombotic occlusion of the main stem of the left coronary artery in a neonate.

Thrombotic coronary arterial occlusion, and myocardial infarction, are rare in the newborn. We report such a happening presenting shortly after birth with cardiogenic shock, no left ventricular output and a systemic circulation dependent on flow from a patent arterial duct.

Neonatal cardiac catheterization: A 10-year transition from diagnosis to therapy.

To assess the changing role of cardiac catheterization in the care of the neonate, a retrospective review of all catheterizations between January 1984 to December 1985 (group I) and January 1994 to December 1995 (group II) at C.S. Mott Children's Hospital was performed. Neonatal cardiac catheterization was performed more frequently (p = 0.02) in group I, comprising 14% (110 of 772) of all catheterizations versus 11% (93 of 880) in group II. Access was performed by cutdown in 15 patients (13 venous and 2 arterial), all in group I. In group I, 20 of 110 patients (18%) had balloon atrial septostomies; no other catheter interventions were performed. Interventions were more frequent (p = 0.003) and varied in group II, including 15 septostomies, 17 balloon valvuloplasties (13 pulmonary and 4 aortic), 2 coil embolizations of collaterals, and 1 cardiac biopsy. Despite the higher prevalence and complexity of interventions in group II, fluoroscopy times (median; range: 16 min; 2-55 vs 16 min; 1-107) were similar in both groups (p = not significant) as well as the prevalence of complications. Neonatal cardiac catheterizations are performed less frequently than they were a decade ago at our institution, and therapeutic interventions have become more common. Despite these changes, fluoroscopy time and the rate of complications have not increased.

Late fenestration closure in the hypoplastic left heart syndrome: comparison of hemodynamic changes.

BACKGROUND AND OBJECTIVES: Although survival of patients with the hypoplastic left heart syndrome treated by staged surgical palliation has improved, hemodynamic data after fenestrated Fontan operation and after fenestration closure have not been reported in this patient population. We sought to describe the hemodynamic status of these patients at cardiac catheterization performed for the purpose of fenestration closure and to compare these data with data from contemporary patients with other forms of univentricular heart. METHODS AND RESULTS: Hemodynamic responses to fenestration closure during cardiac catheterization were reviewed in 40 consecutive patients, including 20 with the hypoplastic left heart syndrome and 20 with other forms of univentricular heart defects. Hemodynamics before fenestration closure (arterial saturation and pressure, Fontan baffle saturation and pressure, pulmonary capillary wedge pressure, systemic arteriovenous oxygen content difference, and right-to-left shunt fraction) were nearly identical between the two groups. Significant (p < 0.05) changes after fenestration closure included increases in arterial saturation (9%), mean arterial pressure (3 mm Hg), and baffle pressure (1 mm Hg) and arteriovenous oxygen content difference (18 ml/L), with near elimination of right-to-left shunting. Cardiac output decreased by 21% and systemic oxygen transport by 13%, with no differences between the two patient groups. Mean baffle pressures were <17 mm Hg in 32 patients (80%). CONCLUSIONS: Hemodynamics after fenestrated Fontan operation and responses to fenestration closure in patients with the hypoplastic left heart syndrome were remarkably similar to that in patients with other univentricular heart defects.

Division of the main pulmonary artery: suboptimal palliation for the patient with a univentricular heart.

We describe a patient in whom a thrombus formed in the distal main pulmonary artery stump after a bidirectional Glenn procedure with division of the main pulmonary artery and in whom a restrictive inlet ventricular septal defect also developed. These findings emphasize the importance of maintaining antegrade flow through the pulmonary trunk and providing dual sources of ventricular outflow with a Damus-Kaye-Stansel anastomosis in patients with a univentricular heart without pulmonary stenosis.

Intraperitoneal hemorrhage associated with transhepatic cardiac catheterization: a report of two cases.

Transhepatic cardiac catheterization has gained increased interest as a novel technique for venous vascular access with few complications. We report important intra-abdominal bleeding encountered in two patients during transhepatic cardiac catheterization. We describe their management and suggest possible nonoperative strategies.

Intermediate-term results of Phase I Food and Drug Administration Trials of buttoned device occlusion of secundum atrial septal defects.

OBJECTIVES: This study was conducted to evaluate the intermediate-term results of the multi-institutional U.S. trial of the buttoned device for transcatheter closure of atrial septal defects (ASDs). BACKGROUND: The trial was conducted in three centers (University of Arizona, University of Michigan and University of Wisconsin) under a Food and Drug Administration (FDA)-approved clinical trial with investigational device exemption. Only short-term follow-up is known. METHODS: All 46 patients who had successful implantation of the device were prospectively followed up. Patients were evaluated at 1, 6 and 12 months after device occlusion and yearly thereafter. RESULTS: This cohort was followed up from 51 to 68 months (mean 60.8, median 62). Patient ages ranged from 1 to 62 years (median 4); weights ranged from 10 to 105 kg (median 18); and stretched ASD sizes were 14 +/- 4 mm (left to right shunts) and 10 +/- 3 mm (right to left shunts). Of the 46 patients, 45 (98%) had effective occlusion of their ASD, and 34 (74%) had complete ASD closure. The incidence of residual shunts decreased from 65% (30 of 46 patients) at 1 month after device placement to 27% (12 of 45 patients) at last follow-up. All residual shunts were quantitated as trivial. Only two patients (4%) required reintervention for significant residual defects. There were no cases of endocarditis or thromboembolism in 224 patient-years of follow-up. CONCLUSIONS: In up to 5.5 years of follow-up, the buttoned device provided effective closure in 98% of patients in whom the device was successfully implanted. The incidence of residual shunts decreased during follow-up, and no instances of endocarditis or thromboembolism were observed.

Hemodynamic and clinical effects of oral levodopa in children with congestive heart failure.

OBJECTIVES: This study was undertaken to evaluate the safety, efficacy and pharmacodynamic variables of oral levodopa in pediatric patients with congestive heart failure refractory to standard therapy. BACKGROUND: Therapeutic options for children with congestive cardiomyopathies are limited to digoxin, diuretic agents and angiotensin-converting enzyme inhibitors. Previous work in adults with congestive heart failure has shown a short-term effectiveness of levodopa and improvement of cardiac function. METHODS: Baseline two-dimensional and M-mode echocardiography, surface electrocardiography, Holter monitoring and exercise testing, when applicable, were performed. Levodopa was administered in a dose escalation scale from 8 mg/kg body weight per dose to 20 mg/kg per dose over 3 days with concomitant metoclopramide and pyridoxine. Catecholamine levels at initiation of the trial and throughout dose escalation were measured, with echocardiographic and electrocardiographic correlation. After 24-h drug washout, cardiac catheterization was performed both before and after administration of levodopa. RESULTS: Between February 1992 and December 1995, nine children (age 10 +/- 1.7 years, weight 27.8 +/- 4.3 kg) were enrolled in this study. At cardiac catheterization, serum dopamine levels rose from 108.5 +/- 59.2 pg/ml to 1,375.8 +/- 567.9 pg/ml (p = 0.03) at 100 +/- 14.8 min after levodopa administration without a significant change in serum norepinephrine or epinephrine levels. Paralleling these increases, there were significant changes in the cardiac index (1.7 +/- 0.3 to 3.2 +/- 0.7 liters/min per m2), stroke volume index (16.1 +/- 3.2 to 31.2 +/- 7.0 ml/m2 per min), oxygen consumption (138.6 +/- 24.4 to 188.3 +/- 30.8 ml/min per m2) and systemic vascular resistance (36.8 +/- 8 to 21.9 +/- 5.5 indexed Wood's units; all p < 0.01). There was a significant reversal of the daily fluid volume output/input ratio from 0.8 +/- 0.1 to 1.2 +/- 0.1 (p < 0.01). Levodopa administration was complicated by hypertension or tachycardia, or both, requiring a dose reduction in three patients, and by significant gastrointestinal distress in one. There was sustained symptomatic improvement a median of 19.5 months after drug initiation in seven of the patients. CONCLUSIONS: These preliminary data support the hemodynamic value of oral levodopa in the treatment of severe congestive heart failure in children.

Usefulness of repeat balloon aortic valvuloplasty in children.

This retrospective study examines all 15 patients who underwent a second balloon dilation procedure for congenital aortic stenosis to determine its safety and efficacy. The recurrent gradient was significantly reduced, but 4 patients had unsatisfactory gradient relief, 3 of whom had previous surgical valvotomies; therefore, we conclude that repeat balloon aortic valvuloplasty is worthwhile, although third balloon dilations may not be beneficial.

Comparison of hospital charges for balloon angioplasty and surgical repair in children with native coarctation of the aorta.

A retrospective review of hospital charges was performed in children > 1 year old with native coarctation of the aorta who underwent balloon angioplasty, primary surgical repair, or elective surgical repair after unsuccessful balloon angioplasty. Hospital charges were less overall in the balloon angioplasty group, although the failure rate was higher.