Variability in radiation dose and image quality: A comparison across fluoroscopy-system vendors, generations of equipment and institutions.

OBJECTIVES: To evaluate differences in radiation dose and image quality across institutions, fluoroscope vendors and generations of fluoroscopes for pediatric cardiac catheterization. BACKGROUND: Increased recognition of the potentially harmful effects of ionizing radiation has spurred technological advances in fluoroscopes, as well as increased focus on optimizing fluoroscope performance. There is currently little understanding of variability in the dose-image quality relationship across institutions, fluoroscope vendor and/or generation of equipment. METHODS: We evaluated latest generation fluoroscopes from Phillips, Siemens, GE, and Toshiba, and an older generation Phillips fluoroscope (release date 2003) at three different institutions. Radiation dose was measured using an anthropomorphic dose-assessment phantom with effective dose in mSv estimated from Monte Carlo simulations. Image quality phantom images were scored on a 12-point scale by three blinded reviewers. RESULTS: Fluoroscope effective doses ranged from 0.04 to 0.14 mSv/1,000 pulses for fluoroscopy with associated composite image quality scores ranging from 8.0 ± 0.6 to 10.4 ± 1.3. For cineangiography, effective doses ranged from 0.17 to 0.57 mSv/1,000 frames with image quality scores ranging from 10.1 ± 0.3 to 11.1 ± 0.3. There was modest correlation between effective dose and image quality (r = 0.67, P = 0.006). The older generation fluoroscope delivered consistently higher doses than the newer generation systems (2.3- to 3.5-fold higher for fluoroscopy; 1.1- to 3.4-fold higher for cineangiography) without appreciable differences in image quality. CONCLUSION: Technological advances have markedly improved fluoroscope performance. Comparing latest generation systems across vendors and institutions, we found variability in the dose-IQ relationship and speculate that this reflects both equipment and institutional optimization practices.

Left main coronary artery stent placement in a 7.0 kg infant with Williams Syndrome.

We report the case of a 9-month-old male with Williams syndrome who underwent patch augmentation of supravalvar aortic stenosis and pulmonary artery stenosis, and required emergent drug-eluting left coronary artery stenting on post-operative day 1 for severe left ventricular dysfunction related to myocardial ischemia.

Percutaneous Removal of Intravascular Pellet Following Penetrating Cardiac Trauma.

There is controversy regarding the management of projectile embolization, a rare complication of penetrating trauma. We present the case of a 5-year-old, 20 kg male with retrograde venous projectile embolization following traumatic injury with a pellet gun. The projectile was successfully removed utilizing a novel, percutaneous approach.

The Australian Royal Commission into Institutional Responses to Child Sexual Abuse and the Roman Catholic Church.

The Australian Royal Commission into Institutional Responses to Child Sexual Abuse received more reports of sexual abuse of minors from victims of personnel from the Catholic Church than from any other source. It looked beyond the circumstances of the individual reports, to the response of Church leaders. It then took the inquiry to the more fundamental issue of the elements of the Church's structure and its unique culture that enabled sexual abuse and supported the hierarchy's counter-productive responses. This commentary looks at the structural and cultural aspects of the institutional Church most directly connected to sexual abuse by clerics and the ensuing cover-up and it examines their theological and historical foundations. The reality that sexual abuse by clerics was not only known but condoned and covered up cannot be justified but it can be explained in great part by the Church's justification for its own structure and the role of its clerics.

Abstract 12670: Variability in Radiation Dose and Image Quality: A Comparison Across Fluoroscopy-system Vendors and Generations of Equipment.

INTRODUCTION: Increased recognition of the potentially harmful effects of ionizing radiation has spurred technological advances to reduce exposure during fluoroscopy. However there is currently little understanding of the dose-image quality (IQ) relationship between fluoroscopy vendors and across generations of equipment used for imaging during pediatric catheterization. METHODS: We evaluated latest generation fluoroscopy systems from Phillips, Siemens, GE and Toshiba, and an older generation Phillips system (2004 release). Fluoroscopy and cineangiography were performed on a tissue simulation anthropomorphic phantom using a standardized imaging approach. Phantom surface exposures were used for Monte Carlo simulations to calculate radiation effective dose, accounting for differences in beam parameters. We also imaged a fluoroscopy IQ phantom to assess contrast-detail and line-per-inch visualization. IQ images were scored by 3 blinded reviewers with scores averaged to produce a composite rating (scale 0-18). To assess the impact of imaging approach we then simulated a neonatal cardiac catheterization incorporating "typical" imaging protocols provided by institutions using the various systems. RESULTS: Effective doses and IQ scores are summarized in the table. Effective doses varied by >400% with the older generation system consistently delivering markedly higher doses. The associated figure summarizes dose and IQ for a simulated neonatal cardiac catheterization which accounts for measured doses as well as the reported institutional imaging parameters summarized in the figure legend. CONCLUSION: These data demonstrate substantial technological improvements in fluoroscopy equipment and may be useful to justify institutional "upgrades". Comparing latest generation systems across vendors and institutions, we found variability in the dose-IQ relationship that reflects both equipment and imaging approach.

Tissue plasminogen activator treatment of bilateral pulmonary emboli in a pediatric patient supported with a ventricular assist device.

Bleeding and thrombosis are well-known potential complications of VAD support. We present a pediatric patient who developed massive bilateral pulmonary emboli while on BiVAD support that was successfully treated with intravenous tPA and bridged to heart transplant.

Identifying predictors of hospital readmission following congenital heart surgery through analysis of a multiinstitutional administrative Database.

BACKGROUND: Despite resource burdens associated with hospital readmission, there remains little multiinstitutional data available to identify children at risk for readmission following congenital heart surgery. METHODS AND RESULTS: Children undergoing congenital heart surgery and discharged home between January of 2011 and December 2012 were identified within the Pediatric Health Information System database, a multiinstitutional collection of clinical and administrative data. Patient discharges were assigned to derivation and validation cohorts for the purposes of predictive model design, with 17 871 discharges meeting inclusion criteria. Readmission within 30 days was noted following 956 (11%) of discharges within the derivation cohort (n = 9104), with a median time to readmission of 9 days (interquartile range [IQR] 5-18 days). Readmissions resulted in a rehospitalization length of stay of 4 days (IQR 2-8 days) and were associated with an intensive care unit (ICU) admission in 36% of cases. Independent perioperative predictors of readmission included Risk Adjustment in Congenital Heart Surgery score of 6 (odds ratio [OR] 2.6, 95% confidence interval [CI] 1.8-3.7, P < .001) and ICU length of stay of at least 7 days (OR 1.9 95% CI 1.6-2.2, P < .001). Demographic predictors included Hispanic ethnicity (OR 1.2, 95% CI 1.1-1.4, P = .014) and government payor status (OR 1.2, 95% CI 1.1-1.4, P = .007). Predictive model performance was modest among validation cohort (c statistic 0.68, 95% CI 0.66-0.69, P < .001). CONCLUSIONS: Readmissions following congenital heart surgery are common and associated with significant resource consumption. While we describe independent predictors that may identify patients at risk for readmission prior to hospital discharge, there likely remains other unreported factors that may contribute to readmission following congenital heart surgery.

Occlusion of the left main coronary artery os by a tethered aortic valve cusp.

We report a 4-month-old girl who presented with poor ventricular function and was found to have occlusion of the left main coronary artery os by a tethered aortic cusp. The patient underwent surgical delamination of the aortic valve leaflet, revealing a normal left coronary os. After operative repair, her left ventricular function improved significantly. This diagnosis should be included in the differential in all children presenting with cardiac dysfunction.

Percutaneous interventions in high-risk patients following Mustard repair of transposition of the great arteries.

OBJECTIVES: To assess safety, efficacy, and intermediate term outcomes of percutaneous interventions in Mustard patients. BACKGROUND: Baffle leaks and obstruction are present in 20% of Mustard survivors. Surgical reintervention is associated with high mortality. METHODS: Retrospective review of percutaneous interventions performed at three adult congenital catheterization programs. RESULTS: Overall, 26 catheterizations and 29 interventions were performed in 22 patients (mean age 32.4 ± 8.3 years). Previous laser pacemaker lead extraction was successful in seven of seven procedures where the lead was at risk. Stent placement was successful in all 18 patients with systemic venous baffle (SVB) obstruction (mean gradient: 6.2 ± 3.4-0.6 ± 1.0 mm Hg; P < 0.01, narrowest diameter 4.5 ± 4.5-17.1 ± 3.9 mm; P < 0.01). Balloon angioplasty was performed in two patients for pulmonary venous baffle (PVB) obstruction with mixed results. Baffle leak interventions included device occlusion (n = 6), coil occlusion (n = 1), and covered stent occlusion (n = 3). Postprocedural residual leaks were demonstrated in three of eight. In two of the three the residual leak was not appreciable at 1-year follow-up. No patient experienced leak or obstruction related symptom recurrence (mean follow-up: 33.4 ± 29.5 months). Complications included one death secondary to ventricular arrhythmia 2 days after PVB angioplasty and device related inferior SVB obstruction with resolution following stent placement. CONCLUSIONS: Stent placement for SVB obstruction following Mustard repair is effective and likely safer than surgical intervention. Baffle leak occlusion can be safely accomplished but residual leaks are common in the short term.

Percutaneous vascular stent implantation as treatment for central vascular obstruction due to fibrosing mediastinitis.

BACKGROUND: Fibrosing Mediastinitis (FM) is a rare complication of infection with Histoplasma capsulatum that can lead to obstruction of pulmonary and systemic vasculature and large airways, often resulting in significant morbidity and mortality. Medical therapy is ineffective, and surgical intervention is often not feasible. Stent implantation offers a potential treatment for vascular obstruction due to FM, but this has not been well studied. METHODS AND RESULTS: We conducted a retrospective review of all patients undergoing cardiac catheterization for FM. Anatomic site of stenosis and hemodynamic information before and after intervention, as well as clinical presentation and follow-up data, were recorded. From 1996 to 2008, 58 patients underwent cardiac catheterization for FM, with intervention performed in 40 (69%). A total of 77 stents were used to relieve 59 lesions (pulmonary artery=26, pulmonary vein=21, and superior vena cava=12). Significant reduction in pressure gradients (P<0.001) and increase in vessel caliber (P<0.001) were seen at all locations. Symptomatic recurrent stenosis requiring further intervention occurred in 11 patients (28%). Median time to recurrence was 115 months. Thirty-two (87%) of 37 patients for whom follow-up was available reported symptomatic improvement after stent placement. PROCEDURE: related complications occurred in 14 patients (24%). Overall mortality was 19%, with the majority of deaths in patients with bilateral disease. Among patients with bilateral disease, intervention was associated with improved survival at 5 years. CONCLUSION: Percutaneous vascular stent implantation is an effective therapy for central vascular obstruction due to FM, providing significant relief of anatomic obstruction and sustained clinical improvement.

Congenitally corrected transposition of the great arteries: a unique case from Iraq.

A severely cyanotic 27-month-old Iraqi child was transferred to the United States for surgical treatment of suspected tetralogy of Fallot. Her diagnostic studies showed dextrocardia, congenitally corrected transposition of the great arteries, hypoplastic left-sided ventricle, interrupted inferior vena cava, and severe pulmonic stenosis. Given the anatomic constraints as well as the absence of long-term medical care, the decision was made to pursue single-ventricle palliation. The patient recovered from a superior cavopulmonary anastomosis without event and has since returned to her native Iraq.

Congenital pulmonary artery stenoses masquerading as chronic thromboembolic disease.

Stenotic pulmonary vascular lesions, often amenable to balloon angioplasty, can erroneously appear to suggest chronic thromboembolic disease on ventilation/perfusion (V/Q) scan. We report a case of multiple peripheral pulmonary artery stenoses and describe radiologic findings and treatment options.

Routine performance of endomyocardial biopsy decreases the incidence of orthotopic heart transplant for myocarditis.

BACKGROUND: In critically ill children presenting with dilated cardiomyopathy (DCM), the presence of myocarditis predicts an improved chance of myocardial recovery. Noninvasive differentiation of myocarditis from other causes of DCM is difficult. However, sensitivity of endomyocardial biopsy has been questioned. METHODS: We reviewed clinical, echocardiographic, catheterization, and pathology data from all children admitted to the intensive care unit with DCM undergoing orthotopic heart transplantation since the inception of our transplant program in 1987 and all patients with definitively diagnosed myocarditis presenting since 1996. RESULTS: Thirty-six patients with DCM underwent orthotopic heart transplantation. Cellular infiltrate was present in 3 of 36 (8.3%) explanted specimens. Pre-transplant biopsy was performed in 81%. No explanted heart demonstrated infiltrates after a negative biopsy. One biopsy was positive with negative explant histology after transplant 6 months later. No patient with biopsy-proven myocarditis died while listed for transplantation. Eleven additional patients with myocarditis did not undergo transplant. Ten have survived and experienced complete (n = 9) or near complete (n = 1) recovery of myocardial function. One patient died shortly after presentation from fulminant myocarditis. The 10 transplant-free survivors could not be easily distinguished from our transplant cohort by clinical features at presentation. CONCLUSION: The incidence of cellular infiltrate in explanted hearts was significantly lower than that previously reported. Potentially, our aggressive myocarditis diagnostic protocol was useful in therapeutic stratification as a cohort of myocarditis patients avoided transplant and experienced complete recovery of myocardial function despite being difficult to distinguish clinically from our DCM transplant cohort at presentation.

Pulmonary venous wedge pressure provides a safe and accurate estimate of pulmonary arterial pressure in children with shunt-dependent pulmonary blood flow.

OBJECTIVES: To compare two methods of pulmonary arterial pressure measurement in children with shunt-dependent pulmonary blood flow. BACKGROUND: In children with shunt-dependent pulmonary blood flow, direct assessment of pulmonary arterial pressure requires passage of a catheter across the shunt. This can be technically difficult and dangerous. Use of the pulmonary venous wedge pressure offers an alternative but has not been validated in this patient population. METHODS: We prospectively studied 18 children with shunt-dependent pulmonary blood flow. Pulmonary venous wedge pressure and directly measured pulmonary arterial pressures were independently assessed by two blinded cardiologists. RESULTS: Directly measured mean pulmonary arterial pressure and pulmonary venous wedge pressure are closely correlated (R2 = 0.80, P < 0.01). Agreement between the two measures is improved at lower mean pressures with greater differences at higher pressures. For 20 of 24 ipsilateral measurements, pulmonary venous wedge pressure was > or = directly measured pulmonary arterial pressure. Pulmonary venous wedge pressure never underestimated pulmonary arterial pressure by more than 3 mm Hg. CONCLUSIONS: Pulmonary venous wedge pressure provides a safe and accurate means of estimating pulmonary arterial pressure in children with shunt-dependent pulmonary blood flow. The slightly lower pressures seen on direct measurement compared with the reverse pulmonary vein may reflect impairment of flow across the shunt by the catheter.

Development of the MAGIC congenital heart disease catheterization database for interventional outcome studies.

As the field of catheter-based therapies for congenital heart disease continues to expand, we lack the evidence-based data to make appropriate therapeutic decisions in the catheterization laboratory. A stumbling block to the determination of evidence-based therapies is our inability to simply and reliably share outcome data across multiple centers. We investigated whether a commonly used congenital heart disease catheterization database program (PedCath) could be used as an automatic catheterization data submission tool to a central database for outcome analysis. To test the feasibility of such a tool for collaborative outcomes research we formed a national group of seven congenital heart disease centers, the Mid-Atlantic Group of Interventional Cardiology, to warehouse and analyze catheterization data. We successfully modified PedCath to transfer the results of catheter-based therapies on 256 therapeutic procedures for atrial septal defect (ASD) closure, coarctation of the aorta angioplasty and stenting, and pulmonary and aortic balloon valvuloplasties over a 13-month pilot period. Short-term follow-up within the 13-month period was received on 31 patients. This study demonstrated the successful development of a simple process, requiring minimal data entry for investigators from around the world to share cardiac catheterization data for long-term outcome determination of catheter-based therapies for congenital heart disease.

Inhaled nitric oxide use in bidirectional Glenn anastomosis for elevated Glenn pressures.

BACKGROUND: Children frequently undergo bidirectional Glenn anastomosis in the staged surgical management of single ventricle physiology. The purpose of our study was to investigate the role of inhaled nitric oxide therapy in children with marked elevations in Glenn pressures after this surgery. METHODS: A retrospective study over a 30-month period was performed. The effect of inhaled nitric oxide therapy was analyzed in children with marked elevations of Glenn pressures resulting in decreased systemic perfusion. Effects on Glenn pressures, respiratory indices, and systemic perfusion were evaluated after initiation of nitric oxide therapy and compared with baseline parameters. RESULTS: Sixteen patients were placed on nitric oxide therapy for marked elevations of Glenn pressures (22.4 +/- 3.9 mm Hg). In the 11 responsive patients, there were significant reductions in Glenn pressures (from 22.4 mm Hg to 17.1 mm Hg, p < 0.001) and significant improvement in partial pressure of oxygen to fraction of inspired oxygen ratio (from 49 to 74.3, p = 0.001) and oxygenation index (from 17 to 12, p = 0.005). There was simultaneous significant reduction in inotrope score (from 14.9 to 11.4, p < 0.001) and fluid volume support (from 11.4 mL/kg to 2.3 mL/kg, p < 0.001) in the responsive patients. Five patients that failed to show any response were found, subsequently, to have an anatomic lesion. CONCLUSIONS: Inhaled nitric oxide produces significant reduction in Glenn pressures and improvement in systemic perfusion and pulmonary gas exchange in patients with marked elevations of Glenn pressures after bidirectional Glenn anastomosis. Patients who fail to respond should be investigated for an anatomic lesion.

Occlusion of the coronary sinus ostium: a danger for cavopulmonary anastomosis.

Coronary sinus (CS) ostial obstruction decompressing through a left superior vena cava is a rare finding and presents unique risks to patients requiring a Glenn anastomosis for single-ventricle palliation. Preoperative diagnosis is imperative in order to avoid inadvertent ligation or coil occlusion. We report three cases with single-ventricle physiology and CS obstruction identified at cardiac catheterization. Balloon occlusion angiography proved valuable in making the diagnosis.