Paul Iaizzo | University of Minnesota - Twin Cities (original) (raw)

Papers by Paul Iaizzo

American Journal of Respiratory and Critical Care Medicine, 2019

Roadways may negatively impact wildlife species through vehicular-related mortality and spatial d... more Roadways may negatively impact wildlife species through vehicular-related mortality and spatial displacement or obstruction. Here we investigated physiological responses, which provide insights into the animal’s perception of its environment. We deployed GPS-collars in combination with cardiac biologgers on American black bears (Ursus americanus; 18 bear-years) in areas with differing road densities across Minnesota, USA. We tested whether bears exhibited acute stress responses, as defined by significant increases in heart rate (HR), associated with road crossings. Maximum HR between successive telemetry locations were, on average, 13 bpm higher when bears were known to cross a road. They crossed a road, on average, once per day. Different demographic groups (males, females with and without cubs) responded similarly. We found stronger HR responses when crossing high-traffic roads relative to low-traffic in half of the bear-year combinations we sampled. Bears crossed high-traffic roads mainly at night, but low traffic roads during daylight. Bear HRs first became elevated when 73−183 meters away from roadways. Our findings suggest that roadways act as an acute stressor, but the magnitude of the stress response appears to be mild. Elevated HRs may reflect an increased vigilance and recognition of threat when preparing to cross a road. Bears’ recognition and alertness to human-related threats is adaptive for living in human-altered landscapes

2021 Design of Medical Devices Conference, 2020

Brain-inspired (neuromorphic) systems realize biological neural principles with Spiking Neural Ne... more Brain-inspired (neuromorphic) systems realize biological neural principles with Spiking Neural Networks (SNN) to provide high-performing, energy-efficient frameworks for robotics, artificial intelligence, and adaptive control. The Neural Engineering Framework (NEF) brings forth a theoretical framework approach for the representation of high-dimensional mathematical constructs with spiking neurons for the implementation of functional large-scale neural networks. Here, we explore the utilization of neuromorphic adaptive control for circadian modulated cardiac pacing by examining the neuromorphic representation of high-dimensional cardiac data. For this study, we have utilized a model from a data set acquired from an American black bear during hibernation. Black bears in Minnesota will hibernate for 4-6 months without eating and drinking while losing little muscle mass and remain relatively normothermic throughout the winter [10]. In the current study, we obtained EEG and ECG data from...

Science Advances, 2020

3D printed patient-specific aortic root models with internal sensor arrays can augment the planni... more 3D printed patient-specific aortic root models with internal sensor arrays can augment the planning of medical procedures.

2018 Design of Medical Devices Conference, Apr 9, 2018

Annals of Biomedical Engineering, 2018

IEEE Transactions on Biomedical Engineering, 2019

IEEE Transactions on Biomedical Engineering, 2018

Conservation Physiology, 2018

Journal of Medical Devices, 2016

Heart rhythm : the official journal of the Heart Rhythm Society, 2014

Phrenic nerve injury, both left and right, is considered a significant complication of cryoballoo... more Phrenic nerve injury, both left and right, is considered a significant complication of cryoballoon ablation for treatment of drug-refractory atrial fibrillation, and functional recovery of the phrenic nerve can take anywhere from hours to months. The purpose of this study was to focus on short periods of cooling to determine the minimal amount of cooling that may terminate nerve function related to cryo ablation. Left and/or right phrenic nerves were dissected from the pericardium and connective tissue of swine (n = 35 preparations). Nerves were placed in a recording chamber modified with a thermocouple array. This apparatus was placed in a digital water bath to maintain an internal chamber temperature of 37°C. Nerves were stimulated proximally with a 1-V, 0.1-ms square wave. Bipolar compound action potentials were recorded proximal and distal to the site of ablation both before and after ablation, then analyzed to determine changes in latency, amplitude, and duration. Temperatures ...

Journal of cardiovascular translational research, 2012

Currently, over 16 million Americans have coronary artery disease (CAD). Consequently, almost eig... more Currently, over 16 million Americans have coronary artery disease (CAD). Consequently, almost eight million Americans have suffered a myocardial infarction (MI). One method of treating CAD and MI is the implantation of an expandable stent within a compromised artery (for example, one partially occluded by atherosclerotic plaque). In 2007 alone, approximately 560,000 Americans received a coronary stent implantation [1]. Novel imaging of the implantation of a coronary artery stent has potential educational benefits for physicians, design engineers, and patients to better understand such procedures and the devices. We employed Visible Heart® methodologies [2] to obtain endoscopic footage of a coronary artery stent implantation within a reanimated human heart. This experimental approach provides unique imaging of the device–tissue interface that can be used for device development to address related issues, such as vessel perforation and stent dislodgement, which cannot be seen as well on fluoroscopy. The endoscopic imaging modality can then be used to evaluate emerging stent technologies. Furthermore, such images could be employed as useful training tools for cardiac interventionalists as well as educational means for explaining these procedures to patients. Method

Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference, 2008

A noninvasive three-dimensional (3D) cardiac electrical imaging (3DCEI) approach, which can estim... more A noninvasive three-dimensional (3D) cardiac electrical imaging (3DCEI) approach, which can estimate the location of the initiation site (IS) of activation and the resultant 3D activation sequence (AS) from body surface potential maps (BSPMs), was validated in an intact large mammalian model (swine) during acute ventricular pacing. Body surface potential mapping and intracavitary noncontact mapping (NCM) were performed simultaneously during pacing from both right ventricular (RV) sites (intramural) and left ventricular (LV) sites (endocardial). Subsequent 3DCEI analyses were performed on the measured BSPMs. In total, 5 RV and 5 LV sites from control and heart failure animals were paced. The averaged localization error of the RV and LV sites were 7.0+/-1.1 mm and 6.6+/-1.9 mm, respectively. The endocardial ASs as a subset of the estimated 3D ASs by 3DCEI were consistent with those reconstructed from the NCM system. The present experimental results demonstrate that the noninvasive 3DC...

Cardiovascular engineering (Dordrecht, Netherlands), 2007

Pacing site is known to influence the contractile state of the ventricle. Non-physiologic pacing ... more Pacing site is known to influence the contractile state of the ventricle. Non-physiologic pacing sites such as the right ventricular apex (RVA) or left ventricular freewall (LVFW) have been shown to decrease the contractile state of normal myocardium, due to abnormal electrical propagation. The impact of pacing at these sites may alter mechanical restitution (MR), a fundamental cardiac property involving the electro-mechanical regulation of contraction. This, in turn, may affect cardiac function. The present study was conducted to determine if pacing site alters the time constant of MR: tau. Anesthetized canines (n = 6) were acutely paced at four sites: right atrium (RA), RVA, right ventricular septum (RVS), and LVFW. MR data was captured by the S1-S2 pacing protocol and used to create MR curves, generating a restitution time constant, tau, at each site. No significant difference in tau was found between pacing sites. A linear regression analysis of MR curves revealed that there was...

Journal of Medical Devices, 2013

Cardiac Electrophysiology Methods and Models, 2010

The intrinsic conduction system of the heart is comprised of several specialized subpopulations o... more The intrinsic conduction system of the heart is comprised of several specialized subpopulations of cells that either spontaneously generate electrical activity (pacemaker cells) or preferentially conduct this excitation throughout the four chambers of the heart in a coordinated fashion. This chapter will discuss some of the details of this anatomy as well as physiological properties of the system. The cardiac action potential underlies signaling within the heart, and various myocyte populations elicit signature waveforms. The recording or active sensing of these action potentials is important in both research and clinical arenas. This chapter aims to provide a basic understanding of the cardiac conduction system, so the reader has a foundation for future research and reading on this topic. The information in this chapter is not comprehensive and should not be used to make decisions related to patient care.

Journal of Medical Devices, 2012

Journal of the American College of Cardiology, 2013