Henri Justino

The ALARA concept in pediatric cardiac catheterization: techniques and tactics for managing radiation dose

The cardiac catheterization laboratory plays an important role in the management of children with congenital heart disease by not only enabling diagnosis but, in many cases, providing definitive therapy. The goal of the ALARA (As Low as Reasonably Achievable) concept as it applies to cardiac catheterization is to provide maximal diagnostic and therapeutic benefit while requiring the lowest possible radiation dose. A number of specific challenges unique to the setting of pediatric cardiac catheterization, such as higher heart rates, smaller cardiovascular structures, smaller body size, and wider variety of unusual anatomic variants with the potential need for relatively lengthy and complex studies, result in relatively high radiation doses (to the patient and, consequently, to laboratory personnel). In addition, the improved survival of patients with complex anatomy (e.g., palliated single ventricle anatomies) implies that many such children with chronic cardiac disease require frequent catheterizations within the first few years of life. These factors, coupled with the increased radiosensitivity of children and a longer lifespan ahead of them in which to possibly develop radiation-related sequelae, converge to create potentially ominous consequences. Attention to basic rules of radiation safety is, therefore, of tremendous importance in the pediatric cardiac catheterization laboratory. This review focuses on the importance of adequate planning of the study, optimizing image formation, management of fluoroscopy and cine angiography parameters, and the use of certain equipment features that might allow the cardiologist to lower the radiation dose without sacrificing image quality.

Pulmonary artery stents: Long-term follow-up†

Objectives: Determine the long‐term outcomes of branch pulmonary artery (PA) stents. Background: PA stents in congenital heart disease effectively relieve stenoses in the short‐term. Published long‐term data are limited. Methods: Patients enrolled in an FDA IDE protocol from 1989–92 were included. Clinical follow‐up and catheterization data were evaluated. Patients were included if >5 year follow‐up data was available or if mortality occurred following the initial procedure. Results: There were five deaths: four due to progression of their underlying heart disease, and one from a complication during a follow‐up catheterization. Clinical data for 43 surviving patients demonstrated 39 patients (91%) are in NYHA class I or II. Seven patients underwent surgical intervention during the follow‐up period (five RV‐PA conduit, two Fontan revisions), but none addressed PA stenosis. Final repeat catheterizations were performed in 36 patients (55 stents) 7.2 ± 4.3 years post stent insertion with 1.2 ± 0.9 further procedures with stent dilations. In this subgroup, the minimum vessel diameter increased from 4.7 ± 1.8 to 13.4 ± 2.4 mm (P < 0.001), and the pressure gradient improved from 41 ± 25 to 9 ± 11 mm Hg (P < 0.001). Higher initial gradient and smaller balloons were associated with a final stent diameter of <14 mm (P = 0.030 and 0.046). Jailed vessels occurred in 49% of stents with abnormal angiographic flow in 18/55. Six repeat catheterizations resulted in complications, including the one procedural death. Conclusion: Stents implants for PA stenoses provide effective improvement in vessel caliber in the long‐term. Although repeat interventions are necessary, this procedure reduces RV pressure and provides an important alternative to surgery for residual PA obstruction.

Twenty-Five Year Experience With Balloon Aortic Valvuloplasty for Congenital Aortic Stenosis

Balloon aortic valvuloplasty (BAV) is the primary therapy for congenital aortic stenosis (AS). Few reports describe long-term outcomes. In this study, a retrospective single-institution review was performed of patients who underwent BAV for congenital AS. The following end points were evaluated: moderate or severe aortic insufficiency (AI) by echocardiography, aortic valve replacement, repeat BAV, surgical aortic valvotomy, and transplantation or death. From 1985 to 2009, 272 patients who underwent BAV at ages 1 day to 30.5 years were followed for 5.8 ± 6.7 years. Transplantation or death occurred in 24 patients (9%) and was associated with depressed baseline left ventricular shortening fraction (LVSF) (p = 0.04). Aortic valve replacement occurred in 42 patients (15%) at a median of 3.5 years (interquartile range 75 days to 5.9 years) after BAV and was associated with post-BAV gradient ≥25 mm Hg (p = 0.02), the presence of post-BAV AI (p = 0.03), and below-average baseline LVSF (p = 0.04). AI was found in 83 patients (31%) at a median of 4.8 years (interquartile range 1.4 to 8.7) and was inversely related to post-BAV gradient ≥25 mm Hg (p <0.04). AI was associated with depressed baseline LVSF (p = 0.02). Repeat valvuloplasty (balloon or surgical) occurred in 37 patients (15%) at a median of 0.51 years (interquartile range 0.10 to 5.15) and was associated with neonatal BAV (p <0.01), post-BAV gradient ≥25 mm Hg (p = 0.03), and depressed baseline LVSF (p = 0.05). In conclusion, BAV confers long-term benefits to most patients with congenital AS. Neonates, patients with post-BAV gradients ≥25 mm Hg, and patients with lower baseline LVSF experienced worse outcomes.

Transcatheter atrial septal defect closure: Modified balloon sizing technique to avoid overstretching the defect and oversizing the Amplatzer septal occluder

The objective of this study was to evaluate a new technique of sizing atrial septal defects (ASDs) for transcatheter device closure. ASD closure using the Amplatzer septal occluder (ASO) device is commonly performed. Complications, including arrhythmias, pericardial effusions, and perforations, may be related to oversizing ASDs and choosing larger devices. Two methods were used to size ASDs using a compliant balloon. In some patients, the balloon was inflated until a waist was visible [(+)waist]; in others, only until no shunting was demonstrable by echocardiogram [echo; (−)waist]. The device was selected and implanted using standard procedure and echo guidance. One hundred seventeen patients underwent secundum ASD closure with an ASO device. There were 43 patients in the (−)waist group and 74 in the (+)waist group. All devices were implanted successfully. The initial echo ASD diameter was larger in the (−)waist group compared to the (+)waist group (P = 0.01). There was a smaller difference between the initial echo and balloon‐sized ASD diameters in the (−)waist group (P < 0.02). ASO device size implanted (in mm greater than echo ASD diameter) was smaller in the (−)waist group (P < 0.01). There were 0/43 complications in the (−)waist group and 5/74 in the (+)waist group. The complete closure rate was the same in both groups. Sizing an ASD by inflating a compliant balloon just until shunting is eliminated, and not until a waist is visible, results in less overstretching of the ASD and selection of a smaller ASO device, achieving similar closure rates and potentially fewer complications. Catheter Cardiovasc Interv 2005;.

Outcomes of transcatheter occlusion of patent ductus arteriosus in infants weighing ≤ 6 kg.

OBJECTIVES We sought to analyze the outcomes of transcatheter patent ductus arteriosus (PDA) occlusion using a variety of devices in infants weighing ≤6 kg. BACKGROUND Indications for transcatheter closure of a PDA in infancy include congestive heart failure and/or failure to thrive. Devices available for small infants may be problematic for various reasons, including sheath size, stiffness of delivery system, and anchoring and retrievability characteristics of the device. The Amplatzer Ductal Occluder is approved by U.S. Food and Drug Administration for children weighing >6 kg and older than 6 months of age. METHODS We performed a multicenter, retrospective analysis of children weighing ≤6 kg in whom transcatheter PDA occlusion was attempted between January 1995 and November 2005 at Texas Childrens Hospital and January 2001 to November 2005 at Childrens Hospital of San Diego. RESULTS A total of 62 patients underwent attempted closure. The mean age at catheterization was 4.7 ± 2.8 months with a mean weight at catheterization of 4.6 ± 0.9 kg. Successful device placement was achieved in 58 of 62 patients (94%). Among those receiving a device, complete occlusion was noted in all 58 patients at either catheterization or last available follow-up. CONCLUSIONS Percutaneous closure of PDA should be considered even in infants ≤6 kg.

Attitudes and Practices of Cardiologists and Surgeons Who Manage HLHS

OBJECTIVE: We conducted a survey to determine which management options pediatric cardiologists and cardiac surgeons in North America discuss and recommend when counseling parents after the diagnosis of hypoplastic left heart syndrome (HLHS). METHODS: Pediatric cardiologists and cardiac surgeons across North America were asked to complete an anonymous, Internet-based survey about their attitudes and practices regarding the management of HLHS. RESULTS: We contacted 1621 pediatric cardiologists and surgeons, of whom 749 (46%) completed the survey. When counseling parents of newborns with HLHS, 99.7% of respondents discussed staged palliative surgery, 67% discussed cardiac transplantation, and 62.2% discussed compassionate care without surgery. Only a minority (14.9%) discussed all of those options. Staged palliative surgery was recommended over cardiac transplantation or compassionate care without surgery by 76.2% of respondents. When counseling parents after prenatal diagnosis of HLHS, 98.8% of respondents discussed continuation of pregnancy with staged palliative surgery after birth, 53.5% discussed continuation of pregnancy with cardiac transplantation after birth, 56.9% discussed continuation of pregnancy with compassionate care after birth, and 74.3% discussed termination of pregnancy. Only 36.5% discussed all of those options. Continuation of pregnancy with staged palliative surgery after birth was recommended over the other options by 56% of respondents. CONCLUSIONS: Virtually all North American pediatric cardiologists and cardiac surgeons surveyed discuss a surgical intervention when counseling parents about the care of their child or fetus with HLHS. However, only a minority discuss all options. Most physicians recommend staged palliative surgery for management of HLHS.

Stent fractures in congenital heart disease

To describe incidence, characteristics, predictive factors, and sequelae of stent fractures in congenital heart disease.

Randomized Trial of Cutting Balloon Compared With High-Pressure Angioplasty for the Treatment of Resistant Pulmonary Artery Stenosis

Background— We sought to determine the safety and efficacy of Cutting Balloon therapy (CB) compared with conventional high-pressure balloon therapy (HPB) for the treatment of pulmonary artery stenosis. Methods and Results— This prospective, randomized, multicenter, investigational device exemption trial compared CB with HPB. Patient eligibility was determined at the precatheterization assessment; vessel eligibility was determined at catheterization. In all vessels, low-pressure balloon dilation to 8 atm was performed, and if it was not successful, the vessel was randomized to CB or HPB. The primary efficacy outcome was percent change in minimum lumen diameter. A core laboratory performed all vessel measurements and angiographic assessment of vessel damage. The primary safety outcome was any serious adverse event attributable to vessel dilation as assessed by the Data and Safety Monitoring Board. Seventy-three patients from 8 institutions were enrolled between 2004 and 2008. In these patients, 72 vessels responded to low-pressure balloon dilation. Of the 173 vessels that met eligibility criteria, 107 were randomized to CB and 66 to HPB. In randomized vessels, CB therapy was associated with greater percent increase in lumen diameter (85% versus 52%; P=0.004). After crossover was introduced, 26 of 47 vessels treated with HPB underwent CB therapy and experienced an additional 48% increase in lumen diameter; the final diameter after CB was 99% greater than the initial diameter. There were no serious adverse events related to treatment in a study vessel. Conclusion— CB therapy for pulmonary artery stenosis not responsive to low-pressure balloon is more effective than HPB therapy and has an equivalent safety profile.

Simultaneous stent implantation to treat bifurcation stenoses in the pulmonary arteries: Initial results and long-term follow up

Background: Balloon angioplasty of bifurcating pulmonary artery (PA) stenoses is often inadequate, and stent treatment often requires simultaneous implantation of two stents. This study evaluates initial results and long‐term follow up of transcatheter stent placement in bifurcating PAs. Methods: This is a retrospective review of patients (pts) who had bifurcating PA stents placed in main and lobar branches from 1993 to 2007. Results: Forty‐nine pts had bifurcating PA stents placed at a median age of 10.9 years (range 1–43 years). The mean minimum vessel diameter increased from 5.7 ± 2.5 mm to 11.0 ± 3.6 mm (P < 0.001), the mean gradient across the stenoses decreased from 37.0 ± 26.9 to 9.2 ± 13 mm Hg (P < 0.001), whereas the mean RV:FA ratio decreased from 0.76 ± 0.29 to 0.53 ± 0.24 (P < 0.001). There was one death due to severe pulmonary hemorrhage. F/U data were available in 38 pts (mean duration 6.3 ± 4.1 years, range 1.2–13.1 years). Thirty pts underwent repeat catheterizations (mean 2.3 ± 2.2 years poststent), with 26 requiring further interventions: Fifteen had balloon angioplasty alone and 11 had additional stents placed. There were no complications at f/u catheterization. Six pts underwent further palliative surgeries, although none for repair of branch PA stenoses. Conclusions: Simultaneous transcatheter placement of bifurcating PA stents provides immediate gradient relief of bifurcating stenoses in the proximal or lobar branch PAs and reduces RV systolic pressure. Further interventions can be safely performed in future procedures, and the presence of stents does not complicate future surgeries.

Aortic valve morphology is associated with outcomes following balloon valvuloplasty for congenital aortic stenosis.

Evaluate the incidence of various morphologic types of congenital AS, and the association between valve morphology and long‐term outcomes, including repeat BAV, AVR, and death/transplant.