A5013594002- Atrial Fibrillation Management and Outcomes
- Cardiac pacing and defibrillation studies
- Cardiac electrophysiology and arrhythmias
- Cardiac Arrhythmias and Treatments
- Advanced MRI Techniques and Applications
- Cardiac Imaging and Diagnostics
- Advanced X-ray and CT Imaging
- Cerebrovascular and Carotid Artery Diseases
- Medical Imaging Techniques and Applications
- Intracranial Aneurysms: Treatment and Complications
- Nanoparticle-Based Drug Delivery
- Thermal Regulation in Medicine
- Ultrasound and Hyperthermia Applications
- Traumatic Brain Injury and Neurovascular Disturbances
- Heart Rate Variability and Autonomic Control
- Cardiac Arrest and Resuscitation
- Acute Kidney Injury Research
- Electrostatic Discharge in Electronics
- Cardiovascular Function and Risk Factors
- Cardiomyopathy and Myosin Studies
- Thermoregulation and physiological responses
- Neurological Complications and Syndromes
- Cardiac Ischemia and Reperfusion
- Angiogenesis and VEGF in Cancer
- Microbial Inactivation Methods
University of California, San Francisco
2012-2024
University of California System
2018-2020
University of California, Berkeley
2019
GE Global Research (United States)
2018
Outcomes Research Consortium
2003
University of Louisville
2003
Cornell University
1997
Indiana University – Purdue University Indianapolis
1997
Indiana University School of Medicine
1997
The Royal Melbourne Hospital
1997
Mild hypothermia reduces myocardial infarct size in small animals; however, the extent of protection large animals with greater thermal mass remains unknown. We evaluated effects mild endovascular cooling on temperature, size, and cardiac output 60- to 80-kg isoflurane-anesthetized pigs. occluded left anterior descending coronary artery for 60 min, followed by reperfusion 3 h. An heat-exchange catheter was used either lower core body temperature 34°C ( n = 11) or maintain at 38°C 11)....
Background A curative atrial fibrillation procedure will most likely rely on creating transmural linear ablative lesions. However, it is currently unknown whether endocardial radiofrequency lesions can create lines of conduction block. Methods and Results In six pigs, intracardiac echocardiography was used to guide the positioning multiple coil array catheters bridge structures in three right locations: (1) from crista terminalis tricuspid annulus; (2) fossa ovalis terminalis; (3) inferior...
Purpose To compare the CT imaging performance of a carboxybetaine zwitterionic–coated tantalum oxide (TaCZ) nanoparticle contrast agent with that conventional iodinated in swine model meant to simulate overweight and obese patients. Materials Methods Four were evaluated inside three different-sized adipose-equivalent encasements emulating abdominal girths 102, 119, 137 cm. Imaging was performed 64–detector row scanner at six scan delays after intravenous injection 240 mg element (Ta or I)...
The sinus P wave arises from a pacemaker complex distributed along the crista terminalis. We investigated feasibility of modification function using graded applications radiofrequency energy terminalis in dogs to achieve rate control.Modification (30 +/- 5% reduction intrinsic heart with retention normal P-wave axis) was performed 11 (group 1). Total ablation (> 50% development low ectopic atrial or junctional rhythm) 4 2). Intracardiac echocardiography used identify as an anatomic marker...
Background Recently, a colony of German shepherd dogs with inherited spontaneous cardiac arrhythmias and associated sudden death has been developed characterized. Due to the median age onset arrhythmia (4.5 months), tendency for occur during REM sleep or after exercise, absence structural heart disease, we hypothesized developmental abnormality sympathetic innervation heart. Methods Results We studied 11 from this colony, ranging in 6 months years, four 7-month-old unrelated as controls....
Background —Heterogeneity of sympathetic innervation is thought to contribute the potential for fatal arrhythmia. However, little known about effects heterogeneous on repolarization. Methods and Results —To assess this relationship, we measured activation recovery intervals (ARIs) from 64 epicardial sites in 11 rabbits studied 2 weeks after regional denervation produced by phenol 4 sham-operated rabbits. ARI results were compared with distribution 3D reconstructions serial autoradiographs [...
Background and Purpose— Numerous studies indicate that mild hypothermia provides substantial neuroprotection. However, current systems transfer insufficient heat to rapidly vary core temperature. We thus evaluated the safety efficacy of endovascular cooling rewarming for induction reversal hypothermia. Methods— In 10 anesthetized pigs (weight, 66±2 kg), a heat-exchange balloon catheter was inserted into inferior vena cava used cool temperature 32°C then rewarm normothermia. Control animals...
Interventional magnetic resonance imaging (MRI) could allow for diagnosis and immediate treatment of ischemic stroke; however, such endovascular catheter-based procedures under MRI guidance are inherently difficult. One major challenge is tracking the tip catheter, as standard fabrication methods building inductively coupled coil markers rigid bulky. Here, we report a new approach that uses aerosol jet deposition to three-dimensional (3-D) print an RF marker on polymer catheter. Our enables...
The lack of safe and reliable methods to sample vascular tissue in situ limits discovery the underlying genetic pathophysiological mechanisms many disorders, including aneurysms. We investigated feasibility comparable efficacy vivo endothelial cell sampling using a spectrum endovascular devices. Using rabbit elastase carotid aneurysm model we evaluated performance existing aneurysmal coils, intracranial stents, stent-like devices collect cells. Additionally, modified subset assess effects...
Purpose To assess the feasibility of a magnetically assisted remote-controlled (MARC) catheter system under magnetic resonance (MR) imaging guidance for performing simple endovascular procedure (ie, renal artery embolization) in vivo and to compare with x-ray determine value MR specific areas where MARC can be improved. Materials Methods In concordance Institutional Animal Care Use Committee protocol, navigation embolization were tested three farm pigs (mean weight 43 kg ± 2 [standard...
BACKGROUND: Frequent premature atrial complexes (PACs) are associated with future incident fibrillation (AF), but whether PACs contribute to development of AF through adverse remodeling has not been studied. This study aimed explore the effect frequent from different sites on in a swine model. METHODS: Forty underwent baseline electrophysiologic studies and echocardiography followed by pacemaker implantations paced (50% burden) at 250-ms coupling intervals for 16 weeks 4 groups: (1) lateral...
Purpose To determine if endovascular chemofiltration with an ionic device (ChemoFilter [CF]) can be used to reduce systemic exposure and off-target biodistribution of doxorubicin (DOX) during hepatic intra-arterial chemotherapy (IAC) in a preclinical model. Materials Methods Hepatic IAC infusions were performed six pigs normal livers. Animals underwent two 10-minute DOX (200 mg) into the common artery. Both treatment group control received initial at 0 minutes second dose 200 minutes. Prior...
Phase imaging derived from equilibrium radionuclide angiography presents the ventricular contraction sequence. It has been widely but only indirectly correlated with sequence of electrical myocardial activation. We sought to determine specific relationship between phase progression and activation, conduction, in order document a noninvasive method that could monitor both. In 7 normal 9 infarcted dogs, angle was epicardial activation map 126 episodes sinus rhythm pacing three sites. each...
We have designed and built a system for correlated x ray CT transmission SPECT emission imaging with an array of photon counting detectors. The scanner operates in third generation fan beam geometry by translating 23 element high purity germanium detector across the to image phantoms small animals. is used obtain object specific, i.e., anatomically accurate, attenuation map reconstruction image. images are reconstructed MLEM code pixel values scaled physical units determining scaling factor...
The pacing site has been shown to influence functional improvement with cardiac resynchronization therapy. We evaluated the effects of on left ventricular (LV) function in an animal model. Equilibrium radionuclide angiography was acquired sinus rhythm (NSR) and pacing, from three sites seven normal eight infarcted dogs. QRS duration, electrical activation pattern, wall motion, LV ejection fraction (EF), synchrony contraction, mean arterial pressure (MAP), were related infarct size, during...
The purpose of this study was to 1) determine the threshold volume coronary microemboli (<120μm) needed for reproducible visualization microinfarcts on contrast enhanced MDCT and MRI 2) assess impact volumes myocardial perfusion left ventricular (LV) function.