Examining Science and Technology/Engineering Educators' Views of Teaching Biomedical Concepts Through Physical Computing.

Programming and automation continue to evolve rapidly and advance the capabilities of science, technology, engineering, and mathematics (STEM) fields. However, physical computing (the integration of programming and interactive physical devices) integrated within biomedical contexts remains an area of limited focus in secondary STEM education programs. As this is an emerging area, many educators may not be well prepared to teach physical computing concepts within authentic biomedical contexts. This shortcoming provided the rationale for this study, to examine if professional development (PD) had a noticeable influence on high school science and technology and engineering (T&E) teachers' (1) perceptions of teaching biomedical and computational thinking (CT) concepts and (2) plans to integrate physical computing within the context of authentic biomedical engineering challenges. The findings revealed a significant difference in the amount of biomedical and CT concepts that teachers planned to implement as a result of the PD. Using a modified version of the Science Teaching Efficacy Belief Instrument (STEBI-A) Riggs and Enochs in Science Education, 74(6), 625-637 (1990), analyses revealed significant gains in teachers' self-efficacy toward teaching both biomedical and CT concepts from the PD. Further analyses revealed that teachers reported increases in their perceived knowledge of biomedical and CT concepts and a significant increase in their intent to collaborate with a science or T&E educator outside of their content area. This study provides implications for researchers and educators to integrate more biomedical and physical computing instruction at the secondary education level.

Pacemaker Lead Placement via Transmural Approach in an Adult With Palliated Single Ventricle Heart Disease.

Given the lack of systemic venous return to the heart, palliated single ventricle patients frequently require epicardial pacemaker implantation for management of dysrhythmias including sinus node dysfunction, atrial arrhythmias, and heart block. Repeated device hardware replacement, frequently required due to high lead thresholds or other device failure, is a challenging and significant problem for this population. 3-dimensional imaging can assist in delineating the cardiac anatomy allowing for novel approaches to intervention. We review a patient with extracardiac Fontan circulation who underwent placement of an endocardial atrial pacemaker lead via a transmural approach with a 3D-printed model used for procedural guidance.

Trisomy 18 and Congenital Heart Disease: Single-Center Review of Outcomes and Parental Perspectives.

BACKGROUND: In patients with trisomy 18, congenital heart surgery is controversial due to anticipated poor patient outcome. Data are lacking regarding clinical outcomes and family opinions about care received. METHODS: A retrospective chart review of patients with trisomy 18 and congenital heart disease from 2005 to 2017 was performed. Patients were grouped into those receiving cardiac intervention (surgery or cardiac catheterization) versus medical management. A telephone survey was used to assess completeness of family counseling provided prior to treatment selection and parental opinions on the care received. RESULTS: Seventeen infants were assessed. In the medical management group (n = 7), there were five deaths at a median age of 1.5 months (range: 1.2-4.1 months) and two survivors aged 29 and 44 months at latest follow-up. In the intervention group (n = 10), cardiac surgery was performed in nine patients at a median age of 4.3 months (0.2-23.4 months) and weight of 3.2 kg (1.5-12.2 kg); catheter intervention was performed in one patient at one week of age. At latest follow-up, seven intervention patients are alive at a median age of 50 months (5-91 months). Survey respondents (n = 12) unanimously stated that their child's quality of life was improved by their specific treatment strategy, that the experience of the parents was enhanced, and that they would choose the same treatment course again. CONCLUSIONS: Surgical repair may be associated with favorable early outcomes and may be judiciously offered in selected circumstances. In this limited experience, parental perceptions were positive regarding the quality of care and overall experience independent of the chosen treatment strategy or eventual outcome.

Pharmacokinetics of intravenous sildenafil in children with palliated single ventricle heart defects: effect of elevated hepatic pressures.

UNLABELLED: Aims Sildenafil is frequently prescribed to children with single ventricle heart defects. These children have unique hepatic physiology with elevated hepatic pressures, which may alter drug pharmacokinetics. We sought to determine the impact of hepatic pressure on sildenafil pharmacokinetics in children with single ventricle heart defects. METHODS: A population pharmacokinetic model was developed using data from 20 single ventricle children receiving single-dose intravenous sildenafil during cardiac catheterisation. Non-linear mixed effect modelling was used for model development, and covariate effects were evaluated based on estimated precision and clinical significance. RESULTS: The analysis included a median (range) of 4 (2-5) pharmacokinetic samples per child. The final structural model was a two-compartment model for sildenafil with a one-compartment model for des-methyl-sildenafil (active metabolite), with assumed 100% sildenafil to des-methyl-sildenafil conversion. Sildenafil clearance was unaffected by hepatic pressure (clearance=0.62 L/hour/kg); however, clearance of des-methyl-sildenafil (1.94×(hepatic pressure/9)(-1.33) L/hour/kg) was predicted to decrease ~7-fold as hepatic pressure increased from 4 to 18 mmHg. Predicted drug exposure was increased by ~1.5-fold in subjects with hepatic pressures ⩾10 versus <10 mmHg (median area under the curve=533 versus 792 µg*h/L). Discussion Elevated hepatic pressure delays clearance of the sildenafil metabolite - des-methyl-sildenafil - and increases drug exposure. We speculate that this results from impaired biliary clearance. Hepatic pressure should be considered when prescribing sildenafil to children. These data demonstrate the importance of pharmacokinetic assessments in patients with unique cardiovascular physiology that may affect drug metabolism.

Surgical approach to a rare case of double-outlet right ventricle and aortopulmonary window.

Although the spectrum of physiology seen in infants and children with double-outlet right ventricle is broad, this anatomy in combination with an aortopulmonary window is extremely rare. We present an interesting case of an infant prenatally diagnosed with this rare CHD. To our knowledge, this is the first report of complete repair in the neonatal period for such a combination of defects.

Sildenafil exposure and hemodynamic effect after Fontan surgery.

OBJECTIVE: Determine sildenafil exposure and hemodynamic effect in children after Fontan single-ventricle surgery. DESIGN: Prospective dose-escalation trial. SETTING: Single-center pediatric catheterization laboratory. PATIENTS: Nine children post Fontan single-ventricle surgical palliation and undergoing elective cardiac catheterization: median (range) age and weight, 5.2 years (2.5-9.4 yr) and 16.3 kg (9.5-28.1 kg). Five children (55%) were boys, and six of nine (67%) had a systemic right ventricle. INTERVENTIONS: Catheterization and echocardiography performed before and immediately after single-dose IV sildenafil (0.25, 0.35, or 0.45 mg/kg over 20 min). MEASUREMENTS AND MAIN RESULTS: Peak sildenafil and desmethyl sildenafil concentration, change in hemodynamic variables measured by cardiac catheterization and echocardiography. Maximum sildenafil concentrations ranged from 124 to 646 ng/mL and were above the in vitro threshold needed for 77% phosphodiesterase type-5 inhibition in eight of nine children and 90% inhibition in seven of seven children with doses more than or equal to 0.35 mg/kg. Sildenafil improved stroke volume (+22%, p = 0.05) and cardiac output (+10%, p = 0.01) with no significant change in heart rate in eight of nine children. Sildenafil also lowered systemic (-16%, p = 0.01) and pulmonary vascular resistance index in all nine children (median baseline pulmonary vascular resistance index 2.4 [range, 1.3-3.7]; decreased to 1.9 [0.8-2.7] Wood Units × m; p = 0.01) with no dose-response effect. Pulmonary arterial pressures decreased (-10%, p = 0.02) and pulmonary blood flow increased (9%, p = 0.02). There was no change in myocardial performance index and no adverse events. CONCLUSIONS: After Fontan surgery, sildenafil infusion acutely improves cardiopulmonary hemodynamics, increasing cardiac index. For the range of doses studied, exposure was within the acute safety range reported in adult subjects.

Abnormal agitated saline study results after tetralogy of Fallot repair.

Residual intracardiac or extracardiac shunting is frequently seen in patients with repaired congenital heart disease and can cause systemic hypoxemia. We present the case of an adult with tetralogy of Fallot who underwent two corrective surgical procedures as a child with subsequent pulmonary valve replacement due to residual pulmonary insufficiency. Further details of her operative history were otherwise unknown. After being lost to follow-up for many years, she presented with unexplained cyanosis and a markedly abnormal agitated saline study on transthoracic echocardiography in which only the left heart filled after contrast administration. We review the differential diagnosis for such a presentation and discuss the utility of cardiac magnetic resonance imaging (MRI) to define the etiology. Cardiac MRI, a frequently used imaging modality to longitudinally assess adult patients with congenital heart disease, provides excellent image quality of cardiac structures and the ability to perform angiography in a variety of imaging planes. These advantages render cardiac MRI, a useful modality to determine the etiology of unexplained cyanosis in these patients as both intracardiac and extracardiac shunts can be detected.

Sildenafil exposure and hemodynamic effect after stage II single-ventricle surgery.

OBJECTIVES: To determine sildenafil exposure and hemodynamic effect in children after stage II single-ventricle surgery. DESIGN: Prospective, dose escalation trial. SETTING: Single-center, pediatric catheterization laboratory. PATIENTS: Twelve children poststage II single-ventricle surgical palliation and undergoing elective cardiac catheterization: median age 1.9 years (range, 0.8, 4.0), weight 11 kg (8, 13), nine females, and 10 with a single right ventricle. INTERVENTIONS: Catheterization and echocardiography performed before and immediately after single-dose IV sildenafil (0.125, 0.25, 0.35, or 0.45 mg/kg over 20 min). MEASUREMENTS: Peak sildenafil and desmethyl sildenafil concentration, change in hemodynamic parameters measured by cardiac catheterization and echocardiography including indexed pulmonary vascular resistance, and myocardial performance. MAIN RESULTS: Maximum sildenafil concentrations ranged from 92 to 775 ng/mL and were above the in vitro threshold needed for 77% phosphodiesterase type 5 (PDE-5) inhibition in 80% of subjects and 90% inhibition in 80% of subjects with doses ≥0.35 mg/kg. Sildenafil lowered pulmonary vascular resistance index in all 12 subjects (median pulmonary vascular resistance index 2.2 [range, 1.6, 7.9]; decreased to 1.7 [1.2, 5.4] WU × m; p < 0.01) with no dose-response effect. Sildenafil improved pulmonary blood flow (+8% [0, 20], p = 0.04) and saturations (+2% [0, 16], p = 0.04) in those with baseline pulmonary vascular resistance index ≥ 2 WU × m (n = 7). Change in saturations correlated inversely with change in pulmonary vascular resistance index (r = 0.74, p < 0.01). Sildenafil also lowered mean blood pressure (-12% [-20, +10]; p = 0.04). There was no change in cardiac index and no effect on myocardial performance. There were no adverse events. CONCLUSIONS: Sildenafil demonstrated nonlinear exposure with high interindividual variability but was well tolerated and effectively lowered pulmonary vascular resistance index in all subjects. Sildenafil did not acutely improve myocardial performance or increase cardiac index.

Maternal autoantibody levels in congenital heart block and potential prophylaxis with antiinflammatory agents.

OBJECTIVE: The importance of maternal autoantibody levels in congenital heart block and elucidation of maternal factors that may reduce disease burden require further clarification. STUDY DESIGN: Pregnancies complicated by maternal anti-Ro antibodies from 2007 through 2011 were retrospectively reviewed. RESULTS: In all, 33 women were followed up throughout pregnancy. Semiquantitative maternal anti-La levels were significantly higher in pregnancies complicated by fetal heart block of any degree (median difference, 227.5; P = .04), but there was no difference in maternal anti-Ro levels. In all, 94% of fetuses maintained normal conduction when the mother was treated with hydroxychloroquine or daily prednisone therapy throughout pregnancy, compared to 59% in the untreated group (odds ratio, 0.1; P = .04). CONCLUSION: Pregnancies complicated by fetal heart block did not have higher levels of maternal anti-Ro antibodies. Maternal anti-La level may be a useful predictor of fetal heart block. Maternal treatment with either hydroxychloroquine or daily low-dose prednisone throughout pregnancy may provide a protective effect.

Do rates of arthritis and chorea predict the incidence of acute rheumatic fever?

BACKGROUND: Acute rheumatic fever (ARF), a major cause of acquired heart disease worldwide, remains a significant public health problem. However, the precise incidence of ARF in Africa, where a large number of cases occur, remains unknown. We hypothesize that focused attention on non-cardiac features of ARF, namely joint manifestations and chorea, might enhance its detection in settings with limited resources. METHODS: This hypothesis was tested by reviewing the medical records at Vanderbilt Children's Hospital from 1998 to 2008. In addition, an extensive literature review of published studies was performed to assess rates of joint findings or chorea in confirmed cases of ARF. RESULTS: Fifty-nine new cases of ARF were diagnosed in children at Vanderbilt from 1998 to 2008. Of these cases, 91% presented with joint manifestations or chorea, and 80% satisfied major Jones criteria findings of polyarthritis or chorea. These findings are consistent with literature published from our region and internationally. CONCLUSIONS: Most patients presenting with ARF have either joint symptoms or chorea, features that could be recognized by community health workers and individuals with limited medical training. The referral of patients presenting with these manifestations for further evaluation might improve detection rates of ARF in resource-limited countries and lead to improved estimates of disease burden.