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1.
J Invasive Cardiol ; 35(11)2023 Nov.
Article in English | MEDLINE | ID: mdl-37992325

ABSTRACT

We present a 73-year-old female with history of rheumatic heart disease status post-mechanical mitral valve on warfarin, valvular atrial fibrillation, and alpha thalassemia who was admitted to an outside hospital with anterior ST-segment myocardial infarction. Coronary angiogram showed occluded left anterior descending artery (LAD) with acute thrombus status post-thrombectomy and balloon angioplasty.


Subject(s)
Atrial Fibrillation , Heart Diseases , Thrombosis , Female , Humans , Aged , Shock, Cardiogenic/diagnosis , Shock, Cardiogenic/etiology , Mitral Valve/diagnostic imaging , Mitral Valve/surgery , Thrombosis/complications , Thrombosis/diagnosis , Thrombectomy
2.
Front Cardiovasc Med ; 9: 969325, 2022.
Article in English | MEDLINE | ID: mdl-36505372

ABSTRACT

Background: Women continue to have worse Coronary Artery Disease (CAD) outcomes than men. The causes of this discrepancy have yet to be fully elucidated. The main objective of this study is to detect gender discrepancies in the diagnosis and treatment of CAD. Methods: We used data analytics to risk stratify ~32,000 patients with CAD of the total 960,129 patients treated at the UCSF Medical Center over an 8 year period. We implemented a multidimensional data analytics framework to trace patients from admission through treatment to create a path of events. Events are any medications or noninvasive and invasive procedures. The time between events for a similar set of paths was calculated. Then, the average waiting time for each step of the treatment was calculated. Finally, we applied statistical analysis to determine differences in time between diagnosis and treatment steps for men and women. Results: There is a significant time difference from the first time of admission to diagnostic Cardiac Catheterization between genders (p-value = 0.000119), while the time difference from diagnostic Cardiac Catheterization to CABG is not statistically significant. Conclusion: Women had a significantly longer interval between their first physician encounter indicative of CAD and their first diagnostic cardiac catheterization compared to men. Avoiding this delay in diagnosis may provide more timely treatment and a better outcome for patients at risk. Finally, we conclude by discussing the impact of the study on improving patient care with early detection and managing individual patients at risk of rapid progression of CAD.

3.
Stud Health Technol Inform ; 290: 1080-1081, 2022 Jun 06.
Article in English | MEDLINE | ID: mdl-35673215

ABSTRACT

Early detection plays a key role to enhance the outcome for Coronary Artery Disease. We utilized a big data analytics platform on ∼32,000 patients to trace patients from the first encounter to CAD treatment. There are significant gender-based differences in patients younger than 60 from the time of the first encounter to Coronary Artery Bypass Grafting with a p-value=0.03. This recognition makes significant changes in outcome by avoiding delay in treatment.


Subject(s)
Coronary Artery Disease , Coronary Artery Bypass/adverse effects , Coronary Artery Disease/diagnosis , Coronary Artery Disease/surgery , Data Science , Electronic Health Records , Female , Humans , Risk Factors , Time-to-Treatment , Treatment Outcome
4.
Stud Health Technol Inform ; 294: 407-408, 2022 May 25.
Article in English | MEDLINE | ID: mdl-35612107

ABSTRACT

The development of an ontology facilitates the organization of the variety of concepts used to describe different terms in different resources. The proposed ontology will facilitate the study of cardiothoracic surgical education and data analytics in electronic medical records (EMR) with the standard vocabulary.


Subject(s)
Biological Ontologies , Data Science , Electronic Health Records , Vocabulary
5.
Stud Health Technol Inform ; 294: 550-554, 2022 May 25.
Article in English | MEDLINE | ID: mdl-35612140

ABSTRACT

The study of precision medicine that measures the effects of social, cultural, and environmental influences on health is essential to improve health outcomes. Race is a social concept used historically to divide, track, control populations, and reinforce social hierarchies. Beyond genetics, race is also a surrogate for other socioeconomic factors affecting patient outcomes. Our data analytics study aims to analyze the Electronic Medical Record (EMR) to study patients of different races in diagnosing and treating Coronary Artery Disease (CAD). We found no race discrepancies at the University of California San Francisco Medical Centers. This study opens several new hypotheses for further research in this crucial field.


Subject(s)
Coronary Artery Disease , Electronic Health Records , Coronary Artery Disease/diagnosis , Coronary Artery Disease/therapy , Data Science , Humans , Precision Medicine , Socioeconomic Factors
6.
Comput Biol Med ; 128: 104095, 2021 01.
Article in English | MEDLINE | ID: mdl-33217660

ABSTRACT

While coronary angiography is the gold standard diagnostic tool for coronary artery disease (CAD), but it is associated with procedural risk, it is an invasive technique requiring arterial puncture, and it subjects the patient to radiation and iodinated contrast exposure. Artificial intelligence (AI) can provide a pretest probability of disease that can be used to triage patients for angiography. This review comprehensively investigates published papers in the domain of CAD detection using different AI techniques from 1991 to 2020, in order to discern broad trends and geographical differences. Moreover, key decision factors affecting CAD diagnosis are identified for different parts of the world by aggregating the results from different studies. In this study, all datasets that have been used for the studies for CAD detection, their properties, and achieved performances using various AI techniques, are presented, compared, and analyzed. In particular, the effectiveness of machine learning (ML) and deep learning (DL) techniques to diagnose and predict CAD are reviewed. From PubMed, Scopus, Ovid MEDLINE, and Google Scholar search, 500 papers were selected to be investigated. Among these selected papers, 256 papers met our criteria and hence were included in this study. Our findings demonstrate that AI-based techniques have been increasingly applied for the detection of CAD since 2008. AI-based techniques that utilized electrocardiography (ECG), demographic characteristics, symptoms, physical examination findings, and heart rate signals, reported high accuracy for the detection of CAD. In these papers, the authors ranked the features based on their assessed clinical importance with ML techniques. The results demonstrate that the attribution of the relative importance of ML features for CAD diagnosis is different among countries. More recently, DL methods have yielded high CAD detection performance using ECG signals, which drives its burgeoning adoption.


Subject(s)
Coronary Artery Disease , Artificial Intelligence , Coronary Angiography , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/epidemiology , Electrocardiography , Humans , Machine Learning
7.
Europace ; 21(11): 1703-1709, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31545350

ABSTRACT

AIMS: Rotating sheaths and laser sheaths are commonly used for transvenous lead extraction. This study aims to compare observed mortality between both approaches. METHODS AND RESULTS: The Manufacturer and User Facility Device Experience database was searched from 2011 to 2016 to determine number of deaths associated with each sheath. An independent analytics firm provided estimates for number of cases done, allowing calculation of market share. A sensitivity analysis was performed to determine relative risk (RR) of mortality at the calculated market share (36% rotating/64% laser) and two others. Additional sensitivity analyses assumed underreporting of deaths associated with rotating sheaths. An estimated 50 545 extractions were performed. Thirteen deaths were associated with rotating sheaths compared to 167 with laser sheaths. Of these, 92% (rotating) and 95% (laser) were due to cardiovascular injury. At the calculated market share, the RR of death was 7.2 times greater with laser sheaths [95% confidence interval (CI) 4.1-12.7, P < 0.0001]. At market share estimates of 25% rotating/75% laser and 45% rotating/55% laser, the RR of death with laser sheaths was 4.3 (95% CI 2.4-7.5, P < 0.0001) and 10.5 times greater (95% CI 6.0-18.5, P < 0.0001), respectively. The RR of death remained significant when assuming deaths with rotating sheaths were underreported and when deaths using both sheaths were attributed to the rotating sheath. CONCLUSIONS: Lead extraction with laser sheaths appears to be associated with a higher risk of mortality compared to rotating sheaths. Further studies are warranted to confirm this finding.


Subject(s)
Arrhythmias, Cardiac/therapy , Device Removal/mortality , Electrodes, Implanted , Arrhythmias, Cardiac/mortality , Device Removal/methods , Equipment Design , Follow-Up Studies , Humans , Retrospective Studies , Survival Rate/trends , United States/epidemiology
8.
Pancreas ; 46(10): 1381-1385, 2017.
Article in English | MEDLINE | ID: mdl-29040196

ABSTRACT

Neuroendocrine tumors (NETs) comprise a heterogeneous group of neoplasms. These tumors can produce a wide variety of hormones that can lead to syndromes of hormone excess, such as carcinoid syndrome. We present the case of a 47-year-old man who presented with right upper quadrant abdominal pain and emesis. He was found to have metastatic pancreatic NET and was treated with systemic chemotherapy. He subsequently developed dyspnea on exertion and was found to have severe right-sided heart disease secondary to elevated levels of serum serotonin. He was successfully treated with surgical tricuspid and pulmonic valve replacement. True carcinoid syndrome with pancreatic NETs is rare, but, as a treatable complication of the disease, is an important entity for which oncologists should be familiar.


Subject(s)
Carcinoid Heart Disease/complications , Neuroendocrine Tumors/complications , Pancreatic Neoplasms/complications , Carcinoid Heart Disease/diagnosis , Carcinoid Heart Disease/therapy , Diagnosis, Differential , Humans , Male , Middle Aged , Syndrome
9.
Int J Comput Assist Radiol Surg ; 12(5): 811-819, 2017 May.
Article in English | MEDLINE | ID: mdl-27882488

ABSTRACT

PURPOSE: To quantify cardiac and respiratory deformations of the thoracic aorta after ascending aortic graft repair. METHODS: Eight patients were scanned with cardiac-resolved computed tomography angiography during inspiratory/expiratory breath-holds. Aortic centerlines and lumen were extracted to compute the arclength, curvature, angulation, and cross-section shape. RESULTS: From systole to diastole, the angle of graft [Formula: see text] arch increased by 2.4[Formula: see text] ± 1.8[Formula: see text] (P < 0.01) and the angle of arch [Formula: see text] descending aorta decreased by 2.4[Formula: see text] ± 2.6[Formula: see text] (P < 0.05), while the effective diameter of the proximal arch decreased by 2.4 ± 1.9% (P < 0.01), a greater change than those of the graft or distal arch (P < 0.05). From inspiration to expiration, the angle of graft [Formula: see text] arch increased by 2.8[Formula: see text] ± 2.6[Formula: see text] (P < 0.02) with the peak curvature increase (P < 0.05). Shorter graft length was correlated with greater cardiac-induced graft [Formula: see text] arch angulation, and longer graft length was correlated with greater respiratory-induced arch [Formula: see text] descending aorta angulation (R [Formula: see text] 0.50). CONCLUSION: The thoracic aorta changed curvature and angulation with cardiac and respiratory influences, driven by aortic root and arch motion. The thoracic aortic geometry and deformation are correlated with the ascending aortic graft length.


Subject(s)
Aorta, Thoracic/surgery , Aorta/surgery , Aortic Dissection/surgery , Motion , Plastic Surgery Procedures/methods , Vascular Surgical Procedures/methods , Aged , Aged, 80 and over , Cardiopulmonary Bypass , Computed Tomography Angiography , Diastole , Female , Humans , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Male , Middle Aged , Systole , Tomography, X-Ray Computed
10.
Stem Cell Res Ther ; 7(1): 84, 2016 Jun 13.
Article in English | MEDLINE | ID: mdl-27296220

ABSTRACT

BACKGROUND: Acute myocardial infarction (MI) leads to an irreversible loss of proper cardiac function. Application of stem cell therapy is an attractive option for MI treatment. Adipose tissue has proven to serve as a rich source of stem cells (ADSCs). Taking into account the different morphogenesis, anatomy, and physiology of adipose tissue, we hypothesized that ADSCs from different adipose tissue depots may exert a diverse multipotency and cardiogenic potential. METHODS: The omental, pericardial, and epicardial adipose tissue samples were obtained from organ donors and patients undergoing heart transplantation at our institution. Human foreskin fibroblasts were used as the control group. Isolated ADSCs were analyzed for adipogenic and osteogenic differentiation capacity and proliferation potential. The immunophenotype and constitutive gene expression of alkaline phosphatase (ALP), GATA4, Nanog, and OCT4 were analyzed. DNA methylation inhibitor 5-azacytidine was exposed to the cells to stimulate the cardiogenesis. Finally, reprogramming towards cardiomyocytes was initiated with exogenous overexpression of seven transcription factors (ESRRG, GATA4, MEF2C, MESP1, MYOCD, TBX5, ZFPM2) previously applied successfully for fibroblast transdifferentiation toward cardiomyocytes. Expression of cardiac troponin T (cTNT) and alpha-actinin (Actn2) was analyzed 3 weeks after initiation of the cardiac differentiation. RESULTS: The multipotent properties of isolated plastic adherent cells were confirmed with expression of CD29, CD44, CD90, and CD105, as well as successful differentiation toward adipocytes and osteocytes; with the highest osteogenic and adipogenic potential for the epicardial and omental ADSCs, respectively. Epicardial ADSCs demonstrated a lower doubling time as compared with the pericardium and omentum-derived cells. Furthermore, epicardial ADSCs revealed higher constitutive expression of ALP and GATA4. Increased Actn2 and cTNT expression was observed after the transduction of seven reprogramming factors, with the highest expression in the epicardial ADSCs, as compared with the other ADSC subtypes and fibroblasts. CONCLUSIONS: Human epicardial ADSCs revealed a higher cardiomyogenic potential as compared with the pericardial and omental ADSC subtypes as well as the fibroblast counterparts. Epicardial ADSCs may thus serve as the valuable subject for further studies on more effective methods of adult stem cell differentiation toward cardiomyocytes.


Subject(s)
Adipocytes/cytology , Omentum/cytology , Pericardium/cytology , Stem Cells/cytology , Actinin/genetics , Actinin/metabolism , Adipocytes/drug effects , Adipocytes/metabolism , Adult , Aged , Alkaline Phosphatase/genetics , Alkaline Phosphatase/metabolism , Antigens, CD/genetics , Antigens, CD/metabolism , Azacitidine/pharmacology , Biomarkers/metabolism , Cell Transdifferentiation , DNA Methylation/drug effects , Female , Fibroblasts/cytology , Fibroblasts/drug effects , Fibroblasts/metabolism , GATA4 Transcription Factor/genetics , GATA4 Transcription Factor/metabolism , Gene Expression , Heart Transplantation , Humans , Male , Middle Aged , Myocytes, Cardiac/cytology , Myocytes, Cardiac/drug effects , Myocytes, Cardiac/metabolism , Nanog Homeobox Protein/genetics , Nanog Homeobox Protein/metabolism , Octamer Transcription Factor-3/genetics , Octamer Transcription Factor-3/metabolism , Omentum/drug effects , Omentum/metabolism , Osteocytes/cytology , Osteocytes/drug effects , Osteocytes/metabolism , Pericardium/drug effects , Pericardium/metabolism , Primary Cell Culture , Stem Cells/drug effects , Stem Cells/metabolism , Transcription Factors/pharmacology , Troponin T/genetics , Troponin T/metabolism
11.
J Vasc Surg Cases Innov Tech ; 2(3): 101-104, 2016 Sep.
Article in English | MEDLINE | ID: mdl-38827208

ABSTRACT

A 62-year-old man underwent an elephant trunk procedure followed by thoracic endovascular aortic repair (TEVAR). Computed tomography angiography-based models were built to quantify volume of the whole aorta and true and false lumens preoperatively, before TEVAR, after TEVAR, and at follow-up at 3, 6, and 12 months. With TEVAR, descending aortic true lumen volume increased by 54%, then increased additionally by 60% during 12 months. The descending aortic false lumen volume regressed continuously for 12 months following TEVAR, with the most rapid rate from 6 to 12 months at 16 cm3/month. TEVAR immediately increased true lumen volume and continued to remodel the true and false lumens throughout the following 12 months.

12.
ACS Nano ; 9(9): 9416-26, 2015 Sep 22.
Article in English | MEDLINE | ID: mdl-26244654

ABSTRACT

Controllable induction of blood vessel formation (angiogenesis) presents an important therapeutic goal in ischemic diseases and is also beneficial in various normal physiological processes. In this study, we have shown that nanoparticles of celecoxib, a lipophilic nonsteroidal anti-inflammatory drug, effectively evoke therapeutic angiogenesis in animal models, in both normal and ischemic organs. Celecoxib is widely considered to inhibit angiogenesis, although a recent study suggests that it can instead promote blood vessel growth in cancer cell lines. The hydrophobic nature of this drug necessitates its administration in nanoparticulate form in order to elicit a perceivable pharmacological response. We developed a facile method for nanoparticle formation by solvent extraction from microemulsions in supercritical carbon dioxide. This method exploits a spontaneous formation of nanometric domains within the microemulsion system and their rapid conversion to nanoparticles by supercritical fluid. The resultant nanoparticles were administered subcutaneously to mice in a biocompatible hydrogel, and caused a 4-fold increase in blood vessel count in normally perfused skin compared with drug-free particles. They were at least as effective in inducing angiogenesis as nanoparticles of deferoxamine, a well-established neovascularization promoter. Next, we evaluated their effect on ischemic tissues in murine model of myocardial infarction. We found that celecoxib nanoparticles were able to induce a significant vascularization of ischemic myocardium and hamper the progression of heart failure, which points toward a new approach for treating ischemia.


Subject(s)
Celecoxib/administration & dosage , Ischemia/drug therapy , Myocardial Infarction/drug therapy , Nanoparticles/administration & dosage , Neovascularization, Physiologic/drug effects , Angiogenesis Inducing Agents/administration & dosage , Angiogenesis Inducing Agents/chemistry , Animals , Blood Vessels/drug effects , Celecoxib/chemistry , Disease Models, Animal , Humans , Ischemia/pathology , Mice , Myocardial Infarction/pathology , Nanoparticles/chemistry
14.
Stem Cells Transl Med ; 4(6): 625-31, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25947338

ABSTRACT

UNLABELLED: Different tissue-engineering approaches have been developed to induce and promote cardiac regeneration; however, the impact of the immune system and its responses to the various scaffold components of the engineered grafts remains unclear. Fibrin-based engineered heart tissue (EHT) was generated from neonatal Lewis (Lew) rat heart cells and transplanted onto the left ventricular surface of three different rat strains: syngeneic Lew, allogeneic Brown Norway, and immunodeficient Rowett Nude rats. Interferon spot frequency assay results showed similar degrees of systemic immune activation in the syngeneic and allogeneic groups, whereas no systemic immune response was detectable in the immunodeficient group (p < .001 vs. syngeneic and allogeneic). Histological analysis revealed much higher local infiltration of CD3- and CD68-positive cells in syngeneic and allogeneic rats than in immunodeficient animals. Enzyme-linked immunospot and immunofluorescence experiments revealed matrix-directed TH1-based rejection in syngeneic recipients without collateral impairment of heart cell survival. Bioluminescence imaging was used for in vivo longitudinal monitoring of transplanted luciferase-positive EHT constructs. Survival was documented in syngeneic and immunodeficient recipients for a period of up to 110 days after transplant, whereas in the allogeneic setting, graft survival was limited to only 14 ± 1 days. EHT strategies using autologous cells are promising approaches for cardiac repair applications. Although fibrin-based scaffold components elicited an immune response in our studies, syngeneic cells carried in the EHT were relatively unaffected. SIGNIFICANCE: An initial insight into immunological consequences after transplantation of engineered heart tissue was gained through this study. Most important, this study was able to demonstrate cell survival despite rejection of matrix components. Generation of syngeneic human engineered heart tissue, possibly using human induced pluripotent stem cell technology with subsequent directed rejection of matrix components, may be a potential future approach to replace diseased myocardium.


Subject(s)
Fibrin/chemistry , Graft Rejection/immunology , Graft Survival/immunology , Myocardium/immunology , Th1 Cells/immunology , Tissue Engineering , Allografts , Animals , Fibrin/immunology , Graft Rejection/pathology , Rats , Tissue Scaffolds , Transplantation, Isogeneic
15.
Int J Surg Case Rep ; 5(12): 927-31, 2014.
Article in English | MEDLINE | ID: mdl-25460438

ABSTRACT

INTRODUCTION: Primary hepatic sarcomas are uncommon malignant neoplasms; prognostic features, natural history, and optimal management of these tumors are not well characterized. PRESENTATION OF CASE: This report describes the management of a 51-year-old patient that underwent a right trisectionectomy for a large hepatic mass found to be a liver sarcoma on pathology. He subsequently developed tumor emboli to his lungs and was discovered to have cardiac intracavitary metastases from his primary tumor. The patient underwent cardiopulmonary bypass and resection of the right-sided heart metastases to prevent further pulmonary sequela of tumor embolization. DISCUSSION: The lack of distinguishing symptoms or imaging characteristics that clearly define hepatic sarcomas makes it challenging to achieve a diagnosis prior to pathologic examination. Metastatic spread is frequently to the lung or pleura, but very rarely seen within the heart. Failure to recognize cardiac metastatic disease will ultimately lead to progressive tumor embolization and cardiac failure if left untreated. CONCLUSION: The most effective therapy for primary liver sarcomas is surgery; radical resection should be performed if possible given the aggressive nature of these tumors to progress and metastasize.

16.
JSLS ; 18(3)2014.
Article in English | MEDLINE | ID: mdl-25392636

ABSTRACT

BACKGROUND AND OBJECTIVES: Thoracic endometriosis is a rare form of extragenital endometriosis with important clinical ramifications. Up to 80% of women with thoracic endometriosis have concomitant abdominopelvic endometriosis, yet the surgical treatment is usually performed with separate procedures. This is the largest published series of the combination of video-assisted thoracoscopic surgery and traditional laparoscopy for the treatment of abdominopelvic and thoracic endometriosis. The objectives of this series are to further evaluate the manifestations of thoracic endometriosis, assess the multidisciplinary surgical approach, and discuss our institution's protocols. METHODS: This is a retrospective, institutional review board-approved case series of 25 consecutive women who underwent combined video-assisted thoracoscopic surgery and traditional laparoscopy for the treatment of abdominopelvic, diaphragmatic, and thoracic endometriosis from January 1, 2008, to September 30, 2013. All surgeries were performed at a tertiary referral center by the same primary surgeons. Data were collected by chart review. RESULTS: Twenty-five patients were included, with a mean age of 37.7 years. Eighty percent of patients had catamenial chest pain, and in 40% this was their only chest complaint. Shoulder pain was noted in 40% of patients, catamenial pneumothorax in 24%, and hemoptysis in 12%. One hundred percent of patients were found to have endometriosis in the pelvis, 100% in the diaphragm, 64% in the chest wall, and 40% in the parenchyma. There were 2 major postoperative complications: 1 diaphragmatic hernia and 1 vaginal cuff hematoma. CONCLUSION: Clinical suspicion and preoperative assessment are crucial in the diagnosis of thoracic endometriosis and allow for a multidisciplinary approach. The combination of video-assisted thoracoscopic surgery and traditional laparoscopy for the treatment of endometriosis optimally addresses the pelvis, diaphragm, and thoracic cavity in a single operation.


Subject(s)
Endometriosis/surgery , Laparoscopy/methods , Pelvis/surgery , Thoracic Diseases/surgery , Thoracic Surgery, Video-Assisted/methods , Adult , Female , Humans , Middle Aged , Retrospective Studies
17.
J Vasc Interv Radiol ; 25(12): 1903-11, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25066591

ABSTRACT

PURPOSE: To quantify aortic arch geometry and in vivo cardiac-induced and respiratory-induced arch translations and arch branch angulations using three-dimensional geometric modeling techniques. MATERIALS AND METHODS: Scanning with electrocardiogram-gated computed tomography angiography during inspiratory and expiratory breath holds was performed in 15 patients (age, 64 y ± 14) with thoracic aortic aneurysms or dissections. From the lumen models, centerlines of the thoracic aorta, brachiocephalic artery, left common carotid artery, and left subclavian artery and their branching ostia positions were quantified. Three-dimensional translation of vessel ostia, branching angles, and their changes secondary to cardiac pulsation and respiration were computed. RESULTS: During expiration, all ostia translated rightward from systole to diastole (P < .035). Regardless of cardiac phase, all ostia translated posteriorly and superiorly from inspiration to expiration (P < .05). Respiration induced greater posterior and superior translations than cardiac pulsation (P < .03). The left common carotid artery branch angled significantly more toward the aortic arch compared with the brachiocephalic artery and left subclavian artery (P < .03). No significant changes in branching angle were found from systole to diastole or inspiration to expiration. CONCLUSIONS: In patients with thoracic aortic aneurysms or dissections, the thoracic aortic arch translated significantly secondary to inspiration and expiration and to a lesser extent secondary to cardiac pulsation. Insignificant branching angle changes suggest that the aortic arch and its branch origins move predominantly in unison.


Subject(s)
Aorta, Thoracic/diagnostic imaging , Aortic Aneurysm, Thoracic/diagnostic imaging , Aortic Dissection/diagnostic imaging , Adult , Aged , Aged, 80 and over , Breath Holding , Electrocardiography/methods , Exhalation/physiology , Female , Humans , Imaging, Three-Dimensional/methods , Male , Middle Aged , Prospective Studies , Tomography, X-Ray Computed/methods
18.
Proc Natl Acad Sci U S A ; 111(22): 7974-9, 2014 Jun 03.
Article in English | MEDLINE | ID: mdl-24843161

ABSTRACT

The ability to implant electronic systems in the human body has led to many medical advances. Progress in semiconductor technology paved the way for devices at the scale of a millimeter or less ("microimplants"), but the miniaturization of the power source remains challenging. Although wireless powering has been demonstrated, energy transfer beyond superficial depths in tissue has so far been limited by large coils (at least a centimeter in diameter) unsuitable for a microimplant. Here, we show that this limitation can be overcome by a method, termed midfield powering, to create a high-energy density region deep in tissue inside of which the power-harvesting structure can be made extremely small. Unlike conventional near-field (inductively coupled) coils, for which coupling is limited by exponential field decay, a patterned metal plate is used to induce spatially confined and adaptive energy transport through propagating modes in tissue. We use this method to power a microimplant (2 mm, 70 mg) capable of closed-chest wireless control of the heart that is orders of magnitude smaller than conventional pacemakers. With exposure levels below human safety thresholds, milliwatt levels of power can be transferred to a deep-tissue (>5 cm) microimplant for both complex electronic function and physiological stimulation. The approach developed here should enable new generations of implantable systems that can be integrated into the body at minimal cost and risk.


Subject(s)
Electronics, Medical/instrumentation , Electronics, Medical/methods , Miniaturization/methods , Models, Theoretical , Prostheses and Implants , Wireless Technology/instrumentation , Animals , Cerebral Cortex , Electric Power Supplies , Electromagnetic Fields , Equipment Design , Heart Ventricles , Humans , Optics and Photonics/instrumentation , Optics and Photonics/methods , Rabbits , Semiconductors , Skin , Swine
19.
J Cardiothorac Vasc Anesth ; 28(3): 467-72, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24731741

ABSTRACT

OBJECTIVE: To assess whether management of acute Stanford type-A aortic dissection differs in patients with congenital anomalies of the aortic arch compared with standard institutional practice. DESIGN: Retrospective analysis of all consecutive patients from 2001 through 2011. SETTING: Quaternary referral center for surgical management of thoracic aortic disease. PARTICIPANTS: All patients with arch anomalies who underwent surgery for acute Stanford type-A aortic dissection during the study period (n = 43). INTERVENTIONS: Surgical management, anesthetic monitoring, and perfusion strategy were analyzed in a retrospective fashion. No new interventions were undertaken as part of this study. MEASUREMENTS AND MAIN RESULTS: Management differed most in patients with an aberrant right subclavian artery (n = 5), because the institutional standard of right axillary artery cannulation with left upper extremity arterial pressure monitoring was not possible. In patients with one of two "bovine" arch patterns (n = 32), management differed in the conduct of selective antegrade cerebral perfusion, which could include clamping above or below the takeoff of the left common carotid artery (and, therefore, produced unilateral or bilateral antegrade cerebral perfusion). All patients with a connective tissue disorder exhibited a bovine arch pattern. Management of patients with a right arch (n = 3) reflected the opposite of management for normal anatomy (for patients with traditional mirror-image branching) or opposite that of the aberrant right subclavian group (for patients who had a corresponding aberrant left subclavian artery). CONCLUSIONS: Rational management reflected the anatomic variations observed. These results support the importance of interdisciplinary planning, especially in an emergency, to optimize outcome.


Subject(s)
Aorta, Thoracic/abnormalities , Aortic Aneurysm, Thoracic/pathology , Aortic Aneurysm, Thoracic/surgery , Aortic Dissection/pathology , Aortic Dissection/surgery , Vascular Surgical Procedures/methods , Adult , Aged , Aortic Dissection/classification , Aortic Aneurysm, Thoracic/classification , Arterial Pressure/physiology , Cohort Studies , Female , Humans , Male , Middle Aged , Monitoring, Intraoperative , Perfusion , Retrospective Studies , Young Adult
20.
Acta Biomater ; 10(5): 2200-8, 2014 May.
Article in English | MEDLINE | ID: mdl-24434537

ABSTRACT

The major risks of pacemaker and implantable cardioverter defibrillator extraction are attributable to the fibrotic tissue that encases them in situ, yet little is known about the cellular and functional properties of this response. In the present research, we performed a histological and mechanical analysis of human tissue collected from the lead-tissue interface to better understand this process and provide insights for the improvement of lead design and extraction. The lead-tissue interface consisted of a thin cellular layer underlying a smooth, acellular surface, followed by a circumferentially organized collagen-rich matrix. 51.8±4.9% of cells were myofibroblasts via immunohistochemistry, with these cells displaying a similar circumferential organization. Upon mechanical testing, samples exhibited a triphasic force-displacement response consisting of a toe region during initial tensioning, a linear elastic region and a yield and failure region. Mean fracture load was 5.6±2.1N, and mean circumferential stress at failure was 9.5±4.1MPa. While the low cellularity and fibrotic composition of tissue observed herein is consistent with a foreign body reaction to an implanted material, the significant myofibroblast response provides a mechanical explanation for the contractile forces complicating extractions. Moreover, the tensile properties of this tissue suggest the feasibility of circumferential mechanical tissue disruption, similar to balloon angioplasty devices, as a novel approach to assist with lead extraction.


Subject(s)
Defibrillators, Implantable/adverse effects , Myocardium/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Biomechanical Phenomena , Cicatrix/pathology , Electrodes , Female , Humans , Male , Middle Aged , Myocardium/ultrastructure , Myofibroblasts/pathology
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