A5028944616- Cardiac pacing and defibrillation studies
- Cardiac Arrhythmias and Treatments
- Hemodynamic Monitoring and Therapy
- Cardiac electrophysiology and arrhythmias
- Atrial Fibrillation Management and Outcomes
- Cardiovascular Function and Risk Factors
- Blood Pressure and Hypertension Studies
- Cardiac Ischemia and Reperfusion
- Cardiac Imaging and Diagnostics
- Heart Rate Variability and Autonomic Control
- Cardiac Arrest and Resuscitation
- Coronary Interventions and Diagnostics
- Cardiovascular Health and Disease Prevention
- Anesthesia and Neurotoxicity Research
- Non-Invasive Vital Sign Monitoring
- ECG Monitoring and Analysis
- Migraine and Headache Studies
- Anesthesia and Sedative Agents
- Renal and Vascular Pathologies
- Electrical and Bioimpedance Tomography
- Cardiac Valve Diseases and Treatments
- Heart Failure Treatment and Management
- Nitric Oxide and Endothelin Effects
- Cardiovascular Conditions and Treatments
- Acute Myocardial Infarction Research
Medtronic (United States)
2011-2024
Santa Rosa Junior College
2024
Medtronic (Ireland)
2003-2007
Milwaukee VA Medical Center
1995-2006
Medical College of Wisconsin
1995-2006
Harper University Hospital
2005-2006
University of Florence
2005-2006
Medtronic (Italy)
2006
Rutgers, The State University of New Jersey
2006
Rhythm (United states)
2006
Conventional dual-chamber pacing maintains atrioventricular synchrony but results in high percentages of ventricular pacing, which causes desynchronization and has been linked to an increased risk atrial fibrillation patients with sinus-node disease.We randomly assigned 1065 disease, intact conduction, a normal QRS interval receive conventional (535 patients) or minimal the use new pacemaker features designed promote preserve prevent (530 patients). The primary end point was time persistent...
BACKGROUND: The SPYRAL HTN-ON MED (Global Clinical Study of Renal Denervation With the Symplicity Spyral Multi-electrode System in Patients Uncontrolled Hypertension Absence Antihypertensive Medications)trial showed significant office and nighttime systolic blood pressure (BP) reductions patients with hypertension following renal denervation (RDN) compared sham-control patients, despite similar 24-hour BP reductions. We antihypertensive medication changes among prespecified subpopulations....
The relative sensitivity and unexplained detection rate of changes in intrathoracic impedance has not been compared with standard heart failure (HF) monitoring using daily weight changes. Fluid Accumulation Status Trial (FAST) prospectively followed 156 HF patients implanted cardioverter-defibrillator or cardiac resynchronization therapy defibrillator devices modified to record a blinded fashion for 537±312 days. Daily were used calculate fluid index that could be prespecified threshold....
Restenosis resulting from neointimal hyperplasia (NH) limits the effectiveness of intravascular stents. Rates restenosis vary with stent geometry, but whether stents affect spatial and temporal distributions wall shear stress (WSS) in vivo is unknown. We tested hypothesis that alterations WSS after implantation predict sites NH rabbit iliac arteries. Antegrade artery was performed under angiography, blood flow measured before casting 14 or 21 days implantation. Iliac domains were obtained...
The combined role of atrial septal lead location and pacing algorithms in the prevention tachyarrhythmias (AT/AF), including both fibrillation flutter, is unknown. We tested hypothesis that could decrease AT/AF frequency patients with leads, bradycardia, paroxysmal AT/AF.A total 298 (age 70 +/- 10 years; 61% male) from 35 centers were implanted a DDDRP system three algorithms. Lead site was randomized at implant to right or nonseptal. Patients 1 month postimplant ON OFF for 3 months then...
Background Recent evidence indicates that volatile anesthetics exert protective effects during myocardial ischemia and reperfusion. The authors tested the hypothesis sevoflurane decreases infarct size by activating adenosine triphosphate-sensitive potassium (K(ATP)) channels reduces time threshold of ischemic preconditioning necessary to protect against infarction. Methods Barbiturate-anesthetized dogs (n = 75) were instrumented for measurement aortic left ventricular pressures maximum rate...
Background The mechanism of the protective actions volatile anesthetics in ischemic myocardium has not been clearly elucidated. role myocardial adenosine triphosphate-regulated potassium (KATP) channels isoflurane-induced enhancement recovery regional contractile function after multiple brief occlusions and reperfusion left anterior descending coronary artery (LAD) was studied dogs anesthetized with barbiturates. Methods Dogs (n = 32) were instrumented to measure ventricular aortic blood...
The clinical application of atrial tachyarrhythmia (AT) episode data stored by implantable devices is presently limited the high proportion inappropriate detection. We quantified percentage AT detection in two with diagnostics and therapies via meta‐analysis episodes from a number trials. AT500 GEM III AT, contain dual chamber logic to discriminate ventricular tachycardia far‐field R wave (FFRW) oversensing using bipolar electrograms. A subset four trials 1,142 patients was considered....
Pacing for Treatment of Atrial Tachyarrhythmias. Introduction: Patients with bradycardia requiring permanent pacing frequently suffer from additional atrial tachyarrhythmias (ATs). This study evaluated the safety and efficacy antitachycardia (ATP) performance AT prevention implemented into a new pacemaker. Methods Results: In patients conventional indications pacing, an investigational DDDRP pacemaker (Medtronic AT500, model 7253) was implanted. The primary objectives were to determine...
Restenosis limits the effectiveness of stents, but mechanisms responsible for this phenomenon remain incompletely described. Stent geometry and expansion during deployment produce alterations in vascular anatomy that may adversely affect wall shear stress (WSS) correlate with neointimal hyperplasia. These considerations have been neglected previous computational fluid dynamics models stent hemodynamics. Thus we tested hypothesis diameter strut properties (e.g., number, width, thickness)...
Abstract Background The success of stent implantation in the restoration blood flow through areas vascular narrowing is limited by restenosis. Several recent studies have suggested that local geometric environment created a deployed may influence regional characteristics and alter distributions wall shear stress (WSS) after implantation, thereby rendering specific vessel more susceptible to neointimal hyperplasia Stents are most frequently implanted curved vessels such as coronary arteries,...
Background: The epidemiology and clinical implications of asymptomatic atrial tachyarrhythmias (AT) including both fibrillation flutter in pacemaker recipients with without arrhythmia history are not well understood. Atrial High Rate Episodes (A‐HIRATE) Pacemaker Patients Trial was designed to identify compare the incidence AT patients previously diagnosed a standard indication for dual chamber pacing, provide useful diagnostic information management. Methods: Four hundred twenty‐seven were...
Abstract Elevated morning and nighttime blood pressures (BP) are associated with increased risk of cardiovascular events such as stroke myocardial infarction. We compared the long-term changes in BP patients uncontrolled hypertension (office systolic between 150 <180 mmHg/diastolic ≥ 90 mmHg; mean ambulatory (SBP) 140 <170 1–3 prescribed antihypertensive medications). Eighty were randomized to RDN or sham control. In taking at least 3 medications 36 months ( N = 23 group; group), 24 h...
Background Clinical interest in xenon has been rekindled recently by new recycling systems that have decreased its relative cost. The cardiovascular effects of were examined isoflurane-anesthetized dogs before and after the development rapid left ventricular (LV) pacing-induced cardiomyopathy. Methods Dogs (n = 10) chronically instrumented to measure aortic LV pressure, subendocardial segment length, blood flow. Hemodynamics recorded, indices systolic diastolic function afterload determined...
The distribution of cardiac output during administration levosimendan, a new myofilament calcium sensitizer, is unknown. We examined and compared the effects pimobendan, milrinone on regional tissue perfusion by use radioactive microsphere technique in barbiturate‐anaesthetized dogs. Haemodynamics blood flow were determined before infusions levosimendan (0.75, 1.5, 3.0 μg kg −1 min ), pimobendan (10, 20, 40 or (1.0, 2.0, 4.0 ). All three drugs caused similar increases heart rate, output,...
The success of vascular stents in the restoration blood flow is limited by restenosis. Recent data generated from computational fluid dynamics (CFD) models suggest that stent geometry may cause local alterations wall shear stress (WSS) have been associated with neointimal hyperplasia and subsequent However, previous CFD studies ignored histological evidence straightening between circumferential struts. We tested hypothesis consideration stent-induced deformation more accurately predict...
Volatile anesthetics depress left ventricular mechanical performance during multiple phases of the cardiac cycle. The effects sevoflurane on systolic and diastolic function have yet to be fully evaluated. This investigation characterized systemic coronary hemodynamic, inotropic, lusitropic actions in chronically instrumented dogs presence absence autonomic nervous system (ANS) reflexes.Because ANS activity may influence volatile vivo, experiments were conducted both ANS-intact ANS-blocked...
A decrease in myofilament sensitivity to Ca2+ has been proposed as a mechanism for reversible contractile dysfunction after ischemia and reperfusion.The direct actions of intracoronary sensitizers on stunned myocardium have not examined. Barbiturate-anesthetized dogs (n = 9) were instrumented measurement left ventricular (LV) aortic blood pressure, cardiac output, anterior descending coronary artery (LAD) flow velocity, subendocardial segment length (percent shortening [%SS]). Dogs subjected...