Supravalvular and Valvular Pulmonary Stenosis: Predictive Features and Responsiveness to Percutaneous Dilation.

Supravalvular pulmonary stenosis (SVPS) is considered a rare form of pulmonary stenosis (PS) and represents both a diagnostic and therapeutic challenge. There currently exist no reliable echocardiographic criteria to accurately predict the supravalvular form. The aims of the study were to describe the response to treatment of the different PS presentations and to outline the diagnostic capacity of echocardiogram to differentiate the SVPS from valvular PS (VPS). This retrospective study included 106 patients who underwent percutaneous angioplasty between 2006 and 2017. Interventional outcomes of patients with SVPS were compared to those of patients with VPS. Diagnosis of VPS vs. SVPS by echocardiogram was compared to diagnosis obtained by angiogram. Echocardiogram yielded a sensitivity of 56%, a specificity of 82.5%, a positive predictive value of 50%, and a negative predictive value of 85.7%. Patients with SVPS had a significantly smaller pulmonary artery to pulmonary valve (PA:PV) ratio. At 6-12 months of follow-up, the VPS group had a mean right ventricular to pulmonary artery (RV-PA) gradient of 21.68 ± 19.85 mmHg compared to 45.27 ± 24.58 mmHg in the SVPS group. Patients with SVPS had a higher rate of reintervention than patients with VPS (32% vs. 6.2%, p < 0.001). There was no difference in major complications between groups, whereas VPS patients had a higher proportion of pulmonary insufficiency. Percutaneous angioplasty for PS is less effective in patients with a supravalvular component. A better understanding of the underlying histopathology of different PS subtypes could lead to development of different techniques to improve outcomes, with fewer reinterventions, in this population.

Combining Adobe Forms and Dropbox to Obtain a Low-Cost Electronic Data Collection System.

BACKGROUND: The method used to collect, store, and analyze data can affect the quality of data obtained. Many studies have shown the advantages of electronic systems over paper. Numerous tools are available for this purpose; however, they tend to be implemented only in high-budget protocols as they tend to be expensive. INTRODUCTION: We report the experience of the Affective Disorders' Clinic of the National Institute of Psychiatry in Mexico City using Adobe Acrobat® Forms combined with Dropbox® as storage and distribution method for clinical protocols. MATERIALS AND METHODS: Adobe Acrobat 9 Pro® was used to create personalized forms to capture data for seven different clinical purposes. Dropbox was used to share the distributed forms with fellow researchers. Completed forms were stored in Dropbox and the main researcher kept the data collection file, from where the forms were gathered for analysis. RESULTS: Sixteen forms created for different clinical purposes had an average of 1.2% missing fields. DISCUSSION: The main drawbacks relate to remote filling and the time spent in fine-tuning complex forms. The main advantages relate to the simplicity of the implementation of the method and the fact that no software other than the one available at the Institute is required. CONCLUSIONS: Compared with other types of electronic data collection systems, the combination of these tools achieves similar goals and is low cost, requiring minimal knowledge of informatics.

Patient-specific Cardio-respiratory Motion Prediction in X-ray Angiography using LSTM Networks.

Objective.To develop a novel patient-specific cardio-respiratory motion prediction approach for X-ray angiography time series based on a simple long short-term memory (LSTM) model.Approach.The cardio-respiratory motion behavior in an X-ray image sequence was represented as a sequence of 2D affine transformation matrices, which provide the displacement information of contrasted moving objects (arteries and medical devices) in a sequence. The displacement information includes translation, rotation, shearing, and scaling in 2D. A many-to-many LSTM model was developed to predict 2D transformation parameters in matrix form for future frames based on previously generated images. The method was developed with 64 simulated phantom datasets (pediatric and adult patients) using a realistic cardio-respiratory motion simulator (XCAT) and was validated using 10 different patient X-ray angiography sequences.Main results.Using this method we achieved less than 1 mm prediction error for complex cardio-respiratory motion prediction. The following mean prediction error values were recorded over all the simulated sequences: 0.39 mm (for both motions), 0.33 mm (for only cardiac motion), and 0.47 mm (for only respiratory motion). The mean prediction error for the patient dataset was 0.58 mm.Significance.This study paves the road for a patient-specific cardio-respiratory motion prediction model, which might improve navigation guidance during cardiac interventions.

Balloon Atrial Septostomy: Does the Balloon Size Matter?

Background: Dextro-transposition of the great arteries is a congenital heart defect with eventually lethal life-threatening consequences of hypoxic low cardiac output. When a balloon atrial septostomy (BAS) is needed, it is performed shortly after birth to create an interatrial shunt and improve systemic blood oxygenation and haemodynamic conditions. In 2019 and 2020, the withdrawal of some balloon atrioseptostomy catheters from the market led to increased use of catheters with different materials, shapes, and sizes. The main objective of this study was to investigate whether the size of the Miller and Fogarty balloon (Edwards Lifesciences) in its 2 variations, the 4.0 cc and the 1.8 cc, had a different impact on the systemic oxygen saturation, on the atrial septal defect (ASD) size, or on the type and frequency of procedure-related complications. Methods: We conducted a retrospective study on 134 consecutive patients diagnosed with dextrotransposition of the great arteries between 2002 and 2018 who underwent BAS in a tertiary paediatric hospital in Canada. Results: BAS resulted in a significant increase in oxygen saturation of 18.91% ± 12.95% points (P < 0.0001) and a significant increase in the resulting ASD by 3.92 ± 1.58 mm (P < 0.0001). There was no significant difference in resulting oxygen saturation (P = 0.8370) or the final ASD size (P = 0.2193) based on the balloon size. Severe or life-threatening complications were rare (1%) with no subsequent patient demise. Conclusions: This is the first study to show that the small balloon is as efficient as the large balloon catheter including in premature patients. This raises the question whether different balloon sizes are necessary.

Contexte: La dextro-transposition des gros vaisseaux (dTGV) est une cardiopathie congénitale dont les conséquences peuvent être mortelles en raison du bas débit cardiaque et de l'état hypoxique. Lorsqu'une septostomie auriculaire par ballonnet est nécessaire, l'intervention est réalisée après la naissance pour créer une communication interauriculaire (CIA); cette ouverture améliore l'oxygénation de la circulation sanguine systémique ainsi que les conditions hémodynamiques. En 2019 et en 2020, le retrait du marché de certains cathéters utilisés lors des septostomies auriculaires par ballonnet a entraîné une hausse de l'usage de nouveaux cathéters offerts en différentes formes et tailles. L'objectif principal de cette étude était de déterminer si la différence de taille des ballonnets de Miller et de Fogarty (Edwards Lifesciences), respectivement de 4,0 cc et de 1,8 cc, a un effet sur la saturation en oxygène de la circulation sanguine systémique, sur la taille de la CIA ou sur le type et la fréquence des complications liées à l'intervention. Méthodologie: Nous avons mené une étude rétrospective comptant 134 patients consécutifs qui ont présenté une dTGV entre 2002 et 2018 et qui ont subi une septostomie auriculaire par ballonnet dans un hôpital pédiatrique tertiaire canadien. Résultats: Les septostomies auriculaires par ballonnet ont donné lieu à une hausse significative de 18,91 ± 12,95 points de pourcentage (p < 0,0001) de la saturation en oxygène et à une hausse significative de 3,92 ± 1,58 mm (p < 0,0001) de la CIA qui a résulté de l'intervention. La taille du ballonnet n'a pas entraîné de différence significative en ce qui concerne la saturation en oxygène qui a résulté de l'intervention (p = 0,8370) ou la taille finale de la CIA (p = 0,2193). Les complications graves ou mettant la vie du patient en danger ont été rares (1 %) et aucun patient n'est décédé suite à l'intervention. Conclusion: Il s'agit de la première étude qui démontre que le petit ballonnet est aussi efficace que le gros ballonnet, y compris chez les enfants prématurés. Cette conclusion soulève la question à savoir si différentes tailles de ballonnets sont nécessaires.

Characterization of blood-mimicking fluids for echocardiography imaging of ventricular septal defects.

PURPOSE: Ventricular septal defects (VSD) are congenital heart malformations and, in severe cases, they require complex interventions under echocardiography guidance. Heart phantoms can be helpful to train and to understand the complex hemodynamics of VSD. The goal of this study was to characterize the best blood mimicking fluids in such heart phantoms for modelling the hemodynamics of VSD patients using echocardiography. METHODS: Four fluid compositions were considered. Distilled water was used as a baseline, while the other three fluids were developed based on physical properties of human blood, such as the viscosity and the refractive index. Three bi-ventricular heart phantoms of three different pediatric patients with complex VSD were designed from preoperative CT imaging. Custom molds were printed in 3-D and the anatomical structure was casted in polyvinyl alcohol cryogel. The VSD in each heart phantom were observed using echocardiography and color Doppler imaging was used for the hemodynamic study. RESULTS: Heart phantoms with blood mimicking fluids of 30% glycerol and 27% glycerol, 10% sodium iodide were found to be anatomically realistic under echocardiography imaging. Hemodynamic parameters such as the pressure gradient and the volume of the shunt were characterized using color Doppler imaging. CONCLUSION: Proper composition of blood mimicking fluids are important for improving the realism in echocardiographic heart phantoms and they contribute to better understand the complex hemodynamic of VSD under echocardiography.

Generative learning approach for radiation dose reduction in X-ray guided cardiac interventions.

BACKGROUND: Navigation guidance in cardiac interventions is provided by X-ray angiography. Cumulative radiation exposure is a serious concern for pediatric cardiac interventions. PURPOSE: A generative learning-based approach is proposed to predict X-ray angiography frames to reduce the radiation exposure for pediatric cardiac interventions while preserving the image quality. METHODS: Frame predictions are based on a model-free motion estimation approach using a long short-term memory architecture and a content predictor using a convolutional neural network structure. The presented model thus estimates contrast-enhanced vascular structures such as the coronary arteries and their motion in X-ray sequences in an end-to-end system. This work was validated with 56 simulated and 52 patients' X-ray angiography sequences. RESULTS: Using the predicted images can reduce the number of pulses by up to three new frames without affecting the image quality. The average required acquisition can drop by 30% per second for a 15 fps acquisition. The average structural similarity index measurement was 97% for the simulated dataset and 82% for the patients' dataset. CONCLUSIONS: Frame prediction using a learning-based method is promising for minimizing radiation dose exposure. The required pulse rate is reduced while preserving the frame rate and the image quality. With proper integration in X-ray angiography systems, this method can pave the way for improved dose management.

Probable Case of Vertical Transmission of SARS-CoV-2 in a Newborn in Mexico.

BACKGROUND: Much remains unknown about the transmission of the SARS-CoV-2 virus. Pregnant women are considered part of the risk population, and vertical transmission of other coronaviruses has been suggested; however, this type of transmission in SARS-CoV-2 is believed to be unlikely. CASE REPORT: A newborn delivered in term via cesarean section to an asymptomatic but COVID-19-positive 35-year-old woman started with respiratory distress in the first 30 min of life. A chest radiograph revealed pneumothorax and ground glass opacities. Ventilatory support with continuous positive airway pressure was needed. Given the respiratory failure and the positive test from the mother, the patient was sampled for SARS-CoV-2 (RT-PCR) at minute 30 of life, with a positive result reported at 36 h of life. No complications had been present during pregnancy, and cardiac screening and blood cultures revealed no other etiologies. CONCLUSION: Vertical transmission was highly likely in this case. Clinicians should be alert and report similar cases.