Highly accelerated compressed sensing 4D flow MRI in congenital and acquired heart disease: comparison of aorta and main pulmonary artery flow parameters with conventional 4D flow MRI in children and young adults.

BACKGROUND: Four-dimensional flow (4D flow) MRI has become a clinically utilized cardiovascular flow assessment tool. However, scans can be lengthy and may require anesthesia in younger children. Adding compressed sensing can decrease scan time, but its impact on hemodynamic data accuracy needs additional assessment. OBJECTIVE: To compare 4D flow hemodynamics acquired with and without compressed sensing. MATERIALS AND METHODS: Twenty-seven patients (median age: 13 [IQR: 9.5] years) underwent conventional and compressed sensing cardiovascular 4D flow following informed consent. Conventional 4D flow was performed using parallel imaging and an acceleration factor of 2. Compressed sensing 4D flow was performed with an acceleration factor of 7.7. Regions of interest were placed to compare flow parameters in the ascending aorta and main pulmonary artery. Paired Student's t-tests, Wilcoxon signed-rank tests, Bland-Altman plots, and intraclass correlation coefficients were conducted. A P-value of < 0.05 was considered statistically significant. RESULTS: Mean scan acquisition time was reduced by 59% using compressed sensing (3.4 vs. 8.2 min, P < 0.001). Flow quantification was similar for compressed sensing and conventional 4D flow for the ascending aorta net flow: 47 vs. 49 ml/beat (P = 0.28); forward flow: 49 vs. 50 ml/beat (P = 0.07), and main pulmonary artery net flow: 49 vs. 51 ml/beat (P = 0.18); forward flow: 50 vs. 55 ml/beat (P = 0.07). Peak systolic velocity was significantly underestimated by compressed sensing 4D flow in the ascending aorta: 114 vs. 128 cm/s (P < 0.001) and main pulmonary artery: 106 vs. 112 cm/s (P = 0.02). CONCLUSION: For both the aorta and main pulmonary artery, compressed sensing 4D flow provided equivalent net and forward flow values compared to conventional 4D flow but underestimated peak systolic velocity. By reducing scan time, compressed sensing 4D flow may decrease the need for anesthesia and increase scanner output without significantly compromising data integrity.

Age Matters: A Comparative Study of RF Heating of Epicardial and Endocardial Electronic Devices in Pediatric and Adult Phantoms during Cardiothoracic MRI.

This study focused on the potential risks of radiofrequency-induced heating of cardiac implantable electronic devices (CIEDs) in children and adults with epicardial and endocardial leads of varying lengths during cardiothoracic MRI scans. Infants and young children are the primary recipients of epicardial CIEDs, though the devices have not been approved as MR conditional by the FDA due to limited data, leading to pediatric hospitals either refusing the MRI service to most pediatric CIED patients or adopting a scan-all strategy based on results from adult studies. The study argues that risk-benefit decisions should be made on an individual basis. We used 120 clinically relevant epicardial and endocardial device configurations in adult and pediatric anthropomorphic phantoms to determine the temperature rise during RF exposure at 1.5 T. The results showed that there was significantly higher RF heating of epicardial leads than endocardial leads in the pediatric phantom, but not in the adult phantom. Additionally, body size and lead length significantly affected RF heating, with RF heating up to 12 °C observed in models based on younger children with short epicardial leads. The study provides evidence-based knowledge on RF-induced heating of CIEDs and highlights the importance of making individual risk-benefit decisions when assessing the potential risks of MRI scans in pediatric CIED patients.

Guide to use of ferumoxytol for hepatic vascular assessment as part of dual contrast MRI.

Magnetic resonance imaging (MRI) assessment of hepatic vasculature can be challenging in the setting of liver disease and liver lesions. The widely used hepatobiliary contrast agent gadoxetate is an extracellular contrast agent that provides excellent soft tissue characterization but has limitations as a vascular contrast agent. Ferumoxytol is an iron oxide nanoparticle with superparamagnetic properties that can be used as blood pool contrast agent to provide dedicated vascular assessment. We provide a detailed protocol for evaluation of pediatric liver vasculature using ferumoxytol, after imaging of the parenchyma with gadoxetate. We provide multiple examples and discuss practical considerations when incorporating ferumoxytol into practice.

Acute Esophageal Necrosis in Acute Pancreatitis-Report of a Case and Endoscopic and Clinical Perspective.

Esophageal stroke, also known as acute esophageal necrosis or Gurvits syndrome, is an entity that has gained more and more recognition in the last two decades. It is also named "black esophagus" because of striking black discoloration of the esophageal mucosa, with an abrupt transition to normal mucosa at the gastroesophageal junction. Its most common clinical presentation is represented by upper gastrointestinal bleeding and esophagogastroduodenoscopy is the main diagnostic tool. Among the etiopathogenetic and multiple predisposing factors described are hypovolemia, shock state, ischemia, congestive heart failure, acute renal failure, infections, trauma, and diabetes mellitus. Current management of this condition consists of treating the underlying pathology, nil per os, and antacid administration in uncomplicated cases. Although most of the cases have favorable prognosis, complications such as pneumomediastinum or esophageal stricture may occur and fatal cases are a consequence of underlying comorbidities.

Branched polyethyleneimine: CHARMM force field and molecular dynamics simulations.

Polyethyleneimine (PEI), one of the non-viral vectors of great interest for gene delivery, was investigated at all-atom level, with particular emphasis on its branched form. We report the extension of our previously published CHARMM force field (FF) for linear PEI, with parameters optimized specifically for branched configurations. A new residue type for the branch connector is introduced and the charges and bonded parameters are derived from ab initio calculations based on a model polymer. The new FF is validated by extensive molecular dynamics simulations of solvated branched PEIs of various protonation fractions and branch lengths. The gyration radii, end-to-end distances, and diffusion coefficients are compared with results for linear PEIs of similar molecular weights and protonation patterns. Solvated complexes of DNA with (linear/branched) PEI were also investigated to determine favorable attachment conformations. The parametrized atomistic force field is suitable for simulations of PEI with arbitrary branching pattern, protonation, and size, and is expected to provide relevant insights regarding optimal conditions for DNA-PEI complex formation.

A comparative study of MRI-induced RF heating in pediatric and adult populations with epicardial and endocardial implantable electronic devices.

Patients with congenital heart defects, inherited arrhythmia syndromes, and congenital disorders of cardiac conduction often receive a cardiac implantable electronic device (CIED). At least 75% of patients with CIEDs will need magnetic resonance imaging (MRI) during their lifetime. In 2011, the US Food and Drug Administration approved the first MR-conditional CIEDs for patients with endocardial systems, in which leads are passed through the vein and affixed to the endocardium. The majority of children, however, receive an epicardial CIED, where leads are directly sewn to the epicardium. Unfortunately, an epicardial CIED is a relative contraindication to MRI due to the unknown risk of RF heating. In this work, we performed anthropomorphic phantom experiments to investigate differences in RF heating between endocardial and epicardial leads in both pediatric and adult-sized phantoms, where adult endocardial CIED was the control. Clinical Relevance-This work provides a quantitative comparison of MRI RF heating of epicardial and endocardial leads in pediatric and adult populations.

Manometric changes of the esophagus in morbidly obese patients.

This prospective study aimed to determine the manometric pattern and the prevalence of esophageal dysmotility in 79 morbidly obese patients selected for laparoscopic sleeve gastrectomy. After clinical evaluation and upper gastrointestinal endoscopy, high-resolution esophageal manometry was performed. The esophageal peristalsis, lower esophageal sphincter (LES) basal pressure, and LES relaxation were evaluated. Demographic data showed a predominance of females (55.70%) and both females and males were in the 5th decade of life. In addition, approximately 3/4 of the patients (78.48%) were from the urban zone. The mean body mass index of the patients was 46.40±6.0069 kg/m2, with a maximum of 61 kg/m2. The LES basal pressure was normal in 59.49% of the patients, with a mean value of 31.40±18.43 mmHg. LES basal hypertonia was observed in 26.58%, and LES hypotonia in 13.93% of patients; 46.84% (37 patients) had abnormal manometric findings: 24.05% (19 patients) had EGJ outflow obstruction, 12.66% (10 patients) ineffective esophageal motility, 3.8% (3 patients) distal esophageal spasm, 3.8% (3 patients) Jackhammer esophagus, 2 cases were suggestive for type 2 achalasia but in asymptomatic patients. Ineffective esophageal motility was not associated with diabetes mellitus type 2 or erosive esophagitis according to our data. Hiatal hernia (HH) was manometrically diagnosed in 23 patients (29.11%). Preoperative high-resolution esophageal manometry in obese patients demonstrated a high prevalence of motility disorders, but in asymptomatic patients, thus in the future, we require more studies and larger cohorts to better appreciate the clinical impact.

Portal vein thrombosis: A concise review (Review).

Portal vein thrombosis (PVT) is a frequent complication in cirrhotic patients, but it may also exist as a basic vascular condition even without any liver damage. Local and systemic factors play a significant role in the pathogenesis of PVT; yet, in practice, more than one factor may be identified. PVT can be considered a result of liver fibrosis and hepatic insufficiency. The JAK2 mutation has been accepted as a factor producing PVT. In general, the anticoagulants are recommended but this therapy should be used carefully in treating patients that associate coagulopathy or thrombocytopenia and esophageal varices. Acute PVT without bowel infarction has a good prognosis. In liver cirrhosis, the mortality due to hemorrhage is higher than in chronic PVT. Therefore, for the patients with PVT, the survival rate is decreased by 55% in two years, due to hepatic insufficiency. Regarding the treatment, LMWH (low molecular weight heparine) is the most utilized in patients with cirrhosis, non-malignancies, infections, or those who are awaiting a liver transplant. DOACs (direct-acting oral anticoagulants) may be used in the rest of the medical conditions, being safe and equal to LMWH.

Impact of laparoscopic sleeve gastrectomy on esophageal physiology.

Introduction. Laparoscopic sleeve gastrectomy (LSG) is a popular weight loss surgery technique, but the impact on esophageal physiology and esophagogastric junction is still debatable. The aim of our study was to evaluate the manometric changes of the lower esophageal sphincter (LES) after LSG in order to indicate LES manometry pre- procedure. Methods. In a prospective study we evaluated clinically, with upper gastrointestinal endoscopy, and high-resolution esophageal manometry 45 morbidly obese patients before, and 6-12 months after LSG. Results. The BMI (body mass index) decreased from 46.28±5.79 kg/m2 to 32.28±4.65 kg/m2 postoperatively (p <0.01), with a reduction of ~14 kg/m2 of BMI, 39.9 (±11.9) kg body weight and 29.9 (± 6.2)% of the TWL (Total Weight Loss index), in a median interval of 7.9 months. Gastroesophageal reflux disease (GERD) prevalence increased from 17.8% to 31.1% postoperatively, with new GERD onset in 22.2%, but mild symptomatology (the median GERD-HRQL score increased from 1.56 to 2.84 points). Postoperatory reflux was associated with lower esophageal sphincter (LES) hypotonia, shortening of LES length and IIGP (increased intragastric pressure). Hiatal hernia repair rate was 17.8%, and proton pump inhibitor consumption 20%. After weight loss, the 10 cases of esophagitis discovered preoperatively cured, but 3 patients were diagnosed with de novo esophagitis. The prevalence of manometric dysmotility after LSG was 28.9%, lower than before surgery (44.4%). Conclusion. Even if GERD remains the main limitation of LSG, the high-resolution esophageal manometry has proved useful and should be implemented in morbidly obese evaluation protocol, to better select the bariatric procedure.

Evolution and Current Results of a Unified Strategy for Sinus Venosus Surgery.

BACKGROUND: Given recent reports of percutaneous closure of sinus venosus atrial septal defects, we reviewed our experience with surgical repair. Owing to the high incidence of arrhythmias with the two-patch technique, since 2001 we have used either one-patch repairs or the Warden procedure. METHODS: A retrospective review was performed of pediatric patients undergoing sinus venosus atrial septal defect repair at our institution from January 1, 1990, to July 1, 2018. Standard demographic data such as echocardiographic and cross-sectional imaging along with operative details and clinical echocardiographic outcomes were collected. RESULTS: The cohort included 144 patients with a median age of 4.3 years (interquartile range, 8.5). Inferior SVASD was present in 24 patients (17%). A single autologous untreated pericardial patch was used for 114 patients (79%), a two-patch technique for 20 patients (14%, last performed in 2000), and a Warden procedure in 10 patients (7%). Median length of stay was 4 days (interquartile range, 2). On echocardiogram follow-up, no patient had pulmonary vein stenosis. One patient who had the Warden procedure required a balloon dilation of the superior caval vein 2 years postoperatively and a stent 3 years later. Two-patch patients were substantially less likely to be in normal sinus rhythm (41%) on postoperative electrocardiograms compared with the other two techniques (81% one-patch and 89% Warden, P = .02). CONCLUSIONS: The great majority of patients with sinus venosus atrial septal defects can be successfully repaired with a single patch of autologous pericardium. We transitioned to using either a single pericardial patch or the Warden procedure, resulting in a higher frequency of normal sinus rhythm on postoperative electrocardiograms.

Transcatheter biventricular conversion in an adult patient with a 1.5 ventricle Glenn palliation and superior vena cava syndrome.

Covered stents have a continually expanding spectrum of applications for patients with congenital heart disease. Here we report use of covered stents to successfully perform a first-in-human percutaneous biventricular conversion of a 1.5 ventricle Glenn palliation in an adult born with pulmonary atresia. This case demonstrates that in patients considered borderline for biventricular repair, surgery can potentially be modified to promote growth of underdeveloped structures and setup for transcatheter biventricular conversion.

Double Aortic Arch With Kommerell Diverticulum.

BACKGROUND: Vascular rings with a Kommerell diverticulum (KD) most commonly occur in patients with a right aortic arch. We report on a less commonly seen subset of vascular ring patients-those with a double aortic arch and a KD. METHODS: Between 2002 and 2017, 66 patients underwent an operation for a double aortic arch. Ten of those patients also had excision of a KD. We performed a retrospective medical record review of these patients to characterize their demographics and outcomes. RESULTS: All 10 patients (7 male, 3 female) had a double aortic arch that was right dominant and also had a KD. The patients were a mean age of 4.9 ± 4.3 years (range, 6 months to 29 years), and median age was 4 years. All patients had preoperative computed tomographic angiography or magnetic resonance imaging and mean compression of the distal trachea of 63% ± 12% (range, 40% to 80%). The distal left arch was atretic in all patients. All patients underwent division of their left aortic arch, division of the ligamentum, and resection of the KD. The left subclavian artery was transferred to the left carotid artery in 2 patients. The mean size of the diverticulum was 9 × 10 mm. There were no major postoperative complications or readmissions. The postoperative length of stay was 3.1 ± 0.8 days. Five of the patients reported no related persisting symptoms. The remaining 5 patients reported substantial symptomatic relief with only minor respiratory symptoms. CONCLUSIONS: Vascular ring patients with a double aortic arch can also have a KD. In addition to dividing the smaller aortic arch and the ligamentum, we recommend excision of the KD.

Descending Aortic Translocation and Right Pulmonary Artery Reimplantation for Midline Descending Aorta and Crossed Pulmonary Arteries in an Infant.

Left mainstem bronchial compression by a midline descending thoracic aorta is a rare anatomic variant. Translocation of the descending thoracic aorta to the ascending aorta has recently been described to treat this condition. We performed an aortic translocation and right pulmonary artery reimplantation in a 4-month-old infant with severe pulmonary hypertension secondary to right pulmonary artery stenosis and left bronchial compression by a midline descending thoracic aorta. The procedure was successful in ameliorating the patient's left mainstem bronchial compression and pulmonary hypertension. Descending aortic translocation should be considered when the left bronchus is compressed causing respiratory symptoms.

MR angiography and 2-D phase-contrast imaging for evaluation of meso-rex bypass function.

BACKGROUND: The meso-Rex bypass restores blood flow to the liver in patients with extrahepatic portal vein thrombosis. Stenosis occurs in some cases, causing the reappearance of portal hypertension. Complications such as thrombocytopenia present on a spectrum and there are currently no guidelines regarding a threshold for endovascular intervention. While Doppler ultrasound (US) is common for routine evaluation, magnetic resonance (MR) angiography with two-dimensional phase-contrast MRI (2-D PC-MRI) may improve the assessment of meso-Rex bypass function. OBJECTIVES: To determine the feasibility and utility of MR angiography with 2-D PC-MRI in evaluating children with meso-Rex bypass and to correlate meso-Rex bypass blood flow to markers of portal hypertension. MATERIALS AND METHODS: MR angiography and 2-D PC-MRI in meso-Rex bypass patients were retrospectively analyzed. Minimum bypass diameter was measured on MR angiography and used to calculate cross-sectional area. Meso-Rex bypass blood flow was measured using 2-D PC-MRI and divided by ascending aortic flow to quantify bypass flow relative to systemic circulation. Platelet and white blood cell counts were recorded. Correlation was performed between minimum bypass area, blood flow and clinical data. RESULTS: Twenty-five children (median age: 9.5 years) with meso-Rex bypass underwent MR angiography and 2-D PC-MRI. The majority of patients were referred to imaging given clinical concern for complications. Eighteen of the 25 patients demonstrated >50% narrowing of the bypass cross-sectional area. The mean platelet count in 19 patients was 127 K/µL. There was a significant correlation between minimum cross-sectional bypass area and bypass flow (rho=0.469, P=0.018) and between bypass flow and platelet counts (r=0.525, P=0.021). CONCLUSION: Two-dimensional PC-MRI can quantify meso-Rex bypass blood flow relative to total systemic flow. In a cohort of 25 children, bypass flow correlated to minimum bypass area and platelet count. Two-dimensional PC-MRI may be valuable alongside MR angiography to assess bypass integrity.

Laparoscopic sleeve gastrectomy and gastroesophageal reflux.

The prevalence of obesity is rising, becoming a medical problem worldwide. Also GERD incidence is higher in obese patients compared with normal weight, with an increased risk of 2.5 of developing symptoms and erosive esophagitis. Different treatment modalities have been proposed to treat obese patients, but bariatric surgery due to its complex interactions via anatomic, physiologic and neurohormonal changes achieved the best long-term results, with sustained weight loss and decrease of complications and mortality caused by obesity. The bariatric surgical procedures can be restrictive: laparoscopic adjustable gastric band (LAGB) and laparoscopic sleeve gastrectomy (LSG), or malabsorptive-restrictive such as Roux-en-Y gastric bypass (RYGB). These surgical procedures may influence esophageal motility and lead to esophageal complications like gastroesophageal reflux disease (GERD) and erosive esophagitis. From the literature we know that the RYGB can ameliorate GERD symptoms, and some bariatric procedures were finally converted to RYGB because of refractory reflux symptoms. For LAGB the results are good at the beginning, but some patients experienced new reflux symptoms in the follow-up period. Recently LSG has become more popular than other complex bariatric procedures, but some follow-up studies report a high risk of GERD after it. This article reviews the results published after LSG regarding gastroesophageal reflux and the mechanisms responsible for GERD in morbidly obese subjects.

Brom Aortoplasty for Supravalvular Aortic Stenosis.

BACKGROUND: Controversy remains regarding the optimal surgical approach for children with supravalvular aortic stenosis (SVAS). METHODS: Since 1997 we have used Brom three-patch aortoplasty for patients with SVAS. We prefer computed tomography (CT) imaging for preoperative evaluation rather than cardiac catheterization as it avoids the well-known morbidity of general anesthesia. The purpose of this study was to present our intermediate-term results of this strategy. RESULTS: Twenty consecutive patients with SVAS were treated with Brom aortoplasty. Mean age was 3.7 ± 5.9 years (median, 1.5 years). Twelve patients had Williams syndrome. Ten patients had preoperative advanced medical imaging (seven CT, three magnetic resonance imaging) and did not have cardiac catheterization. Mean times for cardiopulmonary bypass and cross-clamp were 172 ± 29 minutes and 110 ± 21 minutes, respectively. Ten patients had simultaneous pulmonary artery stenosis patching. Median length of stay was seven days. There was no operative or late mortality. Mean follow-up was 6 ± 5 years. There were no reoperations on the aortic root. Fifteen patients had mild or less aortic insufficiency (AI) and two had moderate AI. One patient who had infant balloon dilation of the aortic valve and postoperative subacute bacterial endocarditis had moderate-to-severe AI and aortic stenosis (AS). One patient had moderate residual SVAS; all others had no AS. No patients had late coronary insufficiency. CONCLUSION: Brom aortoplasty promotes restoration of normal aortic root geometry and relief of coronary ostial stenosis, which is important in preventing myocardial ischemia. Computed tomography imaging is our preferred diagnostic modality. Intermediate-term outcomes are excellent with no recurrent SVAS, coronary events, or reoperations on the aortic valve.

Anomalous Aortic Origin of a Coronary Artery: Symptoms Do Not Correlate With Intramural Length or Ostial Diameter.

BACKGROUND: Anomalous aortic origin of a coronary artery (AAOCA) is a known cause of sudden death. Our hypothesis was that longer intramural length and smaller ostial diameter correlate with preoperative symptoms. If true, this would assist in the decision for surgical indications. We also assessed the accuracy of preoperative imaging to predict intramural length. METHODS: Retrospective analysis of patients who underwent AAOCA unroofing from 2006 to 2014. Patients had preoperative computed tomography angiography (CTA) or magnetic resonance imaging (MRI). Intramural length was measured. Intramural lengths and ostial diameters were also measured intraoperatively (operating room [OR]). Symptoms were noted. Intramural lengths and ostial diameters were compared between patients with and without preoperative symptoms. The accuracy of intramural length measured by CTA/MRI versus the length measured in the OR was assessed using a Bland-Altman analysis. RESULTS: Sixty-six patients underwent surgical repair of AAOCA. Fifty-two (79%) patients were symptomatic and 14 (21%) were asymptomatic. Mean age was 12.4 ± 4.0 years. There was no mortality. There was strong agreement between intramural length measured by CTA/MRI and measured in the OR. There was no significant difference in AAOCA intramural length in the symptomatic (8.6 ± 3.5 mm) and asymptomatic (8.9 ± 2.8 mm, P = .77) patients, which were measured both by CTA/MRI and intraoperatively (symptomatic 7.3 ± 2.5 mm, asymptomatic 6.9 ± 2.8 mm; P = .62). There was also no significant difference in AAOCA ostial diameters between groups (symptomatic = 1.9 ± 0.5 mm, asymptomatic = 1.6 ± 0.5 mm; P = .09). CONCLUSION: Preoperative CTA/MRI was very accurate in predicting the length of surgical unroofing. There was no demonstrable correlation between preoperative symptoms and intramural AAOCA length or AAOCA ostial diameter.