Assessing the Complexity of Human Ventricular Anatomy: Computational Placement of Mapping Catheters in Perfusion- Fixed Human Hearts

2020 ◽  
Author(s):  
Renee C. Brigham ◽  
Rachel L. Gasser ◽  
Tinen L. Iles ◽  
Paul A. Iaizzo
Keyword(s):  
Patient Outcomes ◽  
Ventricular Arrhythmias ◽  
Computational Models ◽  
Balloon Catheter ◽  
Patient Specific ◽  
Cardiac Anatomy ◽  
Ablation Catheter ◽  
Diverse Range ◽  
Electrical Recording ◽  
Assessment Strategies

Abstract Human ventricular cardiac anatomy is extremely complex. Access to the ventricular chambers are often necessary for both mapping and treating ventricular arrhythmias. To date, electrophysiologists who perform these catheter ablations typically rely on fluoroscopy and the patient specific electroanatomical maps they generate so to begin to navigate through these complex functional anatomies. However, limited mapping resolutions do not provide often required insights relative to actual anatomical barriers. Hence, such discordances can lead to larger induced lesion sizes and ultimately, poorer patient outcomes. Here we describe both unique anatomic studies and the development of 3D computational models and assessment strategies for investigating human ventricular anatomies as they relate to arrhythmogenic mapping and therapies. A diverse range of fixed human anatomies were used to study and predict relative distances from an inter-chamber. placed balloon catheter to both true endocardial and epicardial surfaces. This work can be used to inform mapping and ablation catheter designs so to determine and optimize the placements of mapping electrodes to ensure both accurate electrical recording and applied ablations.

scholarly journals Supervised Domain Adaptation for Automated Semantic Segmentation of the Atrial Cavity

Entropy ◽  
2021 ◽  
Vol 23 (7) ◽  
pp. 898
Author(s):  
Marta Saiz-Vivó ◽  
Adrián Colomer ◽  
Carles Fonfría ◽  
Luis Martí-Bonmatí ◽  
Valery Naranjo
Keyword(s):  
High Performance ◽  
Computational Models ◽  
Domain Adaptation ◽  
Semantic Segmentation ◽  
Patient Specific ◽  
Mr Images ◽  
Training Samples ◽  
Volumetric Images ◽  
Acquisition Costs ◽  
Left And Right

Atrial fibrillation (AF) is the most common cardiac arrhythmia. At present, cardiac ablation is the main treatment procedure for AF. To guide and plan this procedure, it is essential for clinicians to obtain patient-specific 3D geometrical models of the atria. For this, there is an interest in automatic image segmentation algorithms, such as deep learning (DL) methods, as opposed to manual segmentation, an error-prone and time-consuming method. However, to optimize DL algorithms, many annotated examples are required, increasing acquisition costs. The aim of this work is to develop automatic and high-performance computational models for left and right atrium (LA and RA) segmentation from a few labelled MRI volumetric images with a 3D Dual U-Net algorithm. For this, a supervised domain adaptation (SDA) method is introduced to infer knowledge from late gadolinium enhanced (LGE) MRI volumetric training samples (80 LA annotated samples) to a network trained with balanced steady-state free precession (bSSFP) MR images of limited number of annotations (19 RA and LA annotated samples). The resulting knowledge-transferred model SDA outperformed the same network trained from scratch in both RA (Dice equals 0.9160) and LA (Dice equals 0.8813) segmentation tasks.

scholarly journals Variation in end-stage renal disease patient outcomes: what we know, what should we know, and how do we find it out?

1993 ◽  
Vol 3 (11) ◽  
pp. 1738-1747
Author(s):  
P Kurtin ◽  
A R Nissenson
Keyword(s):  
Patient Outcomes ◽  
Outcome Measure ◽  
Disease Patient ◽  
Patient Specific ◽  
Quality Cost ◽  
Current State ◽  
Stage Renal Disease ◽  
End Stage ◽  
Esrd Patients

The size and expense of the ESRD program exceed all predictions made when the program was first initiated. Although the effectiveness of dialytic therapy is unquestioned, its value (quality/cost) is actively debated in this era of constricting resources. To better evaluate the quality of the ESRD program, it is essential to first define and quantitate the outcomes of dialytic care. Although mortality is a convenient outcome measure, it may be affected by many patient-specific as well as other factors that must be considered when evaluating and comparing new and existing technologies or advances. Quality of life is only beginning to be used in depth as an outcome measure, and much work is needed to standardize research methodology and thus move this area forward. The following review describes the current state of knowledge regarding outcomes of ESRD patients and proposes areas for future investigation, which should help increase the understanding of the value of the ESRD program to patients, providers, and payors.

scholarly journals DDPM-DEM Simulations of Particulate Flows in Human Tracheobronchial Airways

2013 ◽  
Author(s):  
Yu Feng ◽  
Clement Kleinstreuer
Keyword(s):  
Computational Models ◽  
Phase Model ◽  
Dispersed Phase ◽  
Particulate Flows ◽  
Lagrange Method ◽  
Dense Particle ◽  
Diverse Range ◽  
Particle Flows ◽  
Dominant Feature ◽  
The One

Dense particle-suspension flows in which particle-particle interactions are a dominant feature encompass a diverse range of industrial and geophysical contexts, e.g., slurry pipeline, fluidized beds, debris flows, sediment transport, etc. The one-way dispersed phase model (DPM), i.e., the conventional one-way coupling Euler-Lagrange method is not suitable for dense fluid-particle flows [1]. The reason is that such commercial CFD-software does not consider the contact between the fluid, particles and wall surfaces with respect to particle inertia and material properties. Hence, two-way coupling of the Dense Dispersed Phase Model (DDPM) combined with the Discrete Element Method (DEM) has been introduced into the commercial CFD software via in-house codes. As a result, more comprehensive and robust computational models based on the DDPM-DEM method have been developed, which can accurately predict the dynamics of dense particle suspensions. Focusing on the interaction forces between particles and the combination of discrete and continuum phases, inhaled aerosol transport and deposition in the idealized tracheobronchial airways [2] was simulated and analyzed, generating more physical insight. In addition, it allows for comparisons between different numerical methods, i.e., the classical one-way Euler-Lagrange method, two-way Euler-Lagrange method, EL-ER method [3], and the present DDPM-DEM method, considering micron- and nano-particle transport and deposition in human lungs.

Abstract WP45: Outcomes of Patients With Cerebral Large Vessel Occlusions Undergoing Mechanical Endovascular Revascularization Based on the Quantification of Pial Collateral Perfusion

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Rizwan Tahir ◽  
Horia Marin ◽  
Muhammad Affan ◽  
Ayesha Ahmad ◽  
Michael Bazydlo ◽  
...  
Keyword(s):  
Stroke Volume ◽  
Patient Outcomes ◽  
Perfusion Pressure ◽  
Large Vessel ◽  
Patient Specific ◽  
P Value ◽  
Vessel Occlusion ◽  
Post Procedure ◽  
Endovascular Revascularization ◽  
Unit Increase

Introduction: Patient outcomes after Mechanical Endovascular Revascularization (MER) are dependent on both patient-specific and procedure-specific factors. The pial collateral perfusion to the ischemic penumbra during a cerebral large vessel occlusion (LVO) is one of the most important factors in overall patient outcome. Using our technique of Quantifying of Pial Collateral Perfusion (QPCP) previously described, patient outcomes after MER for cerebral LVO were assessed. Methods: Fifty consecutive patients with proximal middle cerebral artery M1 occlusions for whom QPCP were recorded were included in the study. In addition to patient demographics, the primary outcomes investigated were National Institutes of Health Stroke Scale (NIHSS) scores post-procedure reduction compared to pre-procedure score, and modified Rankin Scale (mRS) score at 30-day and 3-month follow-up. In addition, overall stroke volume, time spent in hospital, and the incidence of hemorrhagic conversion were also assessed. Regression models were used to estimate the association between pial collateral perfusion pressure and the above outcomes. Results: Patients demonstrated for every 5-unit increase in pial collateral perfusion pressure (measured in mmHg) an association with a 0.54-unit decrease in the post-procedure NIHSS score with a P-value of 0.07 (β= -0.54; 95% CI -1.12,0.03). A 5-unit increase in pial collateral perfusion pressure was also associated with 11% lower odds of having a 30-day mRS of 4-5 vs. 0-1 or 2-3 with a P-value of 0.18 (OR=0.89; 95% CI 0.75,1.06). A higher pial collateral perfusion pressure was also associated with a 0.07-unit decrease in the log of the stroke volume (P-value - 0.32). There was no association with higher pial collateral perfusion pressure and incidence of hemorrhagic conversion on post-procedure imaging. Conclusions: The QPCP is an objective measure for predicting patient outcomes after MER for cerebral LVO. Higher pial collateral perfusion pressures are associated with greater improvements in post-reperfusion NIHSS scores and 30-day mRS scores.

scholarly journals Effect of a Multidisciplinary-Assisted Resident Diabetes Clinic on Resident Knowledge and Patient Outcomes

2013 ◽  
Vol 5 (1) ◽  
pp. 145-149 ◽  
Author(s):  
Margaret C. Lo ◽  
Morganna Freeman ◽  
M. Cecilia Lansang
Keyword(s):  
Patient Outcomes ◽  
Large Scale ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Patient Specific ◽  
Team Approach ◽  
Diabetes Knowledge ◽  
Diabetes Clinic ◽  
Practice Behavior ◽  
Patients With Diabetes

Abstract Background Despite the rising prevalence of diabetes, there is a paucity of diabetes curricula in residency training. The multidisciplinary diabetes team approach is underused in residency education. Objective To assess the feasibility of an innovative multidisciplinary resident diabetes clinic (MRDC) in enhancing (1) resident diabetes knowledge via a Diabetes Awareness Questionnaire, and (2) subsequent process and patient outcomes in patients with diabetes via a Diabetes Practice Behavior Checklist. Methods From October 2008 to February 2010, 14 internal medicine residents managed patients with uncontrolled diabetes in a weekly half-day MRDC for 1 month (total 4–5 half-day sessions/resident), with a collaborative team of internists, diabetes educators, an endocrinologist, and a pharmacist. The curriculum included didactic sessions, required readings, and patient-specific case discussions. A 20-question Diabetes Awareness Questionnaire was administered to each resident prerotation and postrotation. Records of 47 patients with diabetes in the residents' own continuity clinics (not the MRDC) were audited 6 months before and after the MRDC for Diabetes Practice Behavior Checklist measures (glycated hemoglobin, blood pressure, low-density lipoprotein cholesterol, retinal referral, foot exam, microalbumin screen). Pre-MRDC and post-MRDC data were compared via paired t test. Results The MRDC residents exhibited a modest increase in mean (SD) scores on the Diabetes Awareness Questionnaire (before, 8.2 [2.8]; after, 10.9 [2.8]; P  =  .02) and a modest mean (SD) performance increase in overall process outcomes from the Diabetes Practice Behavior Checklist (before, 74% [18%]; after, 84% [18%]; P  =  .004). No improvements occurred in patient outcomes. Conclusions Multidisciplinary diabetes teaching may be useful in fostering certain resident knowledge and performance measures but may not alter clinical outcomes. Further large-scale, longitudinal studies are needed to understand the effect of our curriculum on residents' diabetes knowledge and future practice behavior.

scholarly journals 87Non-invasive virtual prediction of site of origin in outflow tract ventricular arrhythmias with a patient-specific computational model

2017 ◽  
Vol 38 (suppl_1) ◽  
Author(s):  
R. Doste ◽  
D. Soto-Iglesias ◽  
G. Bernardino ◽  
R. Sebastian ◽  
M. Sermesant ◽  
...  
Keyword(s):  
Computational Model ◽  
Ventricular Arrhythmias ◽  
Outflow Tract ◽  
Patient Specific

Improved clinical outcomes in pressure ulcer prevention using the SEM scanner

2019 ◽  
Vol 28 (5) ◽  
pp. 278-282 ◽  
Author(s):  
Glenn Smith
Keyword(s):  
Risk Assessment ◽  
Patient Outcomes ◽  
Pressure Ulcer ◽  
Tissue Injury ◽  
Skin Damage ◽  
Pressure Ulcer Prevention ◽  
Surgical Ward ◽  
Objective Evidence ◽  
Prevention Interventions ◽  
Assessment Strategies

Objective: An in-practice evaluation of an sub-epidermal moisture (SEM) scanner, to detect non-visible pressure damage, allowing appropriate, targeted pressure ulcer (PU) prevention interventions. Method: The evaluation included patients on a single medical-surgical ward over a period of two months. Results: The evaluation included 35 patients. The outcomes of the evaluation suggest that the SEM scanner provided objective evidence that both the interventions being employed and the increase in repositioning and assessment prevented further incipient skin damage. Conclusion: We conclude that the early detection of non-visible tissue injury using the SEM scanner as an adjunct to the usual PU risk assessment strategies can reduce PU incidence, leading to improved patient outcomes and released productivity.

From Donor to Recipient: Considerations for Blood Transfusion Outcomes Research

2017 ◽  
Vol 19 (5) ◽  
pp. 491-498
Author(s):  
Allison R. Jones ◽  
Michelle R. Brown ◽  
David E. Vance
Keyword(s):  
Patient Care ◽  
Patient Outcomes ◽  
Outcomes Research ◽  
Current Evidence ◽  
Patient Specific ◽  
Blood Component ◽  
Blood Components ◽  
Packed Red Blood Cells ◽  
Blood Component Transfusion ◽  
Donor Characteristics

Donated blood can be broken down into blood components for use in patient care. This article focuses primarily on packed red blood cells (PRBCs), as they experience breakdown during storage that may adversely impact patient outcomes. Patients require PRBC transfusions for a number of clinical reasons. Although transfusions of PRBCs provide some clinical benefit, they are also associated with increased morbidity and mortality across multiple patient populations, albeit the mechanisms underlying this relationship remain unclear. With an aging, more acutely ill population requiring aggressive treatment and a lack of transfusion alternatives, research focused on PRBCs has gained momentum. Proper interpretation of research findings on the part of clinicians depends on accurate data collection that includes aspects of both the transfused blood components and the recipients. The purpose of this article is to examine stored PRBC factors, blood-donor characteristics, transfusion-specific factors, and patient-specific characteristics as they relate to patient outcomes research. Challenges associated with performing and interpreting outcomes of transfusion-related research are presented. Implications of current evidence for patient care, such as awareness of benefits as well as risks associated with blood component transfusion, are also provided.

Accuracy of Cartilage Geometry Reconstruction From Volumetric CT Data: A Phantom Study

2007 ◽  
Author(s):  
Andrew E. Anderson ◽  
Benjamin J. Ellis ◽  
Christopher L. Peters ◽  
Jeffrey A. Weiss
Keyword(s):  
Articular Cartilage ◽  
Contrast Agent ◽  
Computational Models ◽  
Image Data ◽  
Cartilage Thickness ◽  
Patient Specific ◽  
Joint Spacing ◽  
Ct Arthrography ◽  
Diarthrodial Joints ◽  
Joint Contact

Segmentation of medical image data is often used for the construction of computational models to study the mechanics of diarthrodial joints such as the hip and knee. The analyst must demonstrate that the reconstructed geometry is an accurate representation of the true continuum to ensure model validity. This becomes especially important for computational modeling of joint contact, which requires accurate reconstruction of articular cartilage. Although volumetric computed tomography (CT) is often used to image diarthrodial joints, the lower bounds for detecting articular cartilage thickness and the influence of imaging parameters on the ability to image cartilage have not been reported. The use of contrast agent (CT arthrography) is necessary to visualize the surface of articular cartilage in live patients. Thus, it is of primary interest to quantify the accuracy of CT arthrography to demonstrate the feasibility of patient-specific modeling. The objectives of this study were to assess the accuracy and detection limits of CT for measuring simulated cartilage thickness using a phantom and to quantify changes in accuracy due to alterations in contrast agent concentration, imaging plane direction, spatial resolution and joint spacing.

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