For more than 50 years, it has been assumed that ventricular fibrillation (VF) is maintained solely by reentry in the working myocardium. This hypothesis has never been tested by recording VF with electrodes spaced sufficiently close to map activation sequences in 3D. We recorded the first 10 minutes of electrically induced VF from the anterior left ventricular (LV) free wall near the insertion...

Full power rating three-level neutral-point clamped (3L-NPC) back-to-back power converters seem promising for wind turbine systems with high power. Direct Model Predictive Control (DMPC) is an attractive technique, in particular, for multi-level converters. Voltage sensorless control makes the voltage measurements obsolete. This work proposes and verifies an Initial Bias Compensation based Virt...

BACKGROUND Previous studies showed that endocardial activation during long-duration ventricular fibrillation (VF) exhibits organized activity. We identified and quantified the different types of organized activity. METHODS AND RESULTS Two 64-electrode basket catheters were inserted, respectively, into the left ventricle and right ventricle of dogs to record endocardial activation from the end...

BACKGROUND Right ventricular failure (RVF) in pulmonary hypertension (PH) is associated with increased incidence of sudden death by a poorly explored mechanism. We test the hypothesis that PH promotes spontaneous ventricular fibrillation (VF) during a critical post-PH onset period characterized by a sudden increase in mortality. METHODS AND RESULTS Rats received either a single subcutaneous d...

BACKGROUND There is the controversy concerning the main component of tobacco, which is responsible for its arrhythmogenesis. In addition, there is the lack of adequate information about the influence of combination of black tea and nicotine on heart rhythm. OBJECTIVES This study aimed to examine whether pretreatment with black tea and nicotine could modulate the susceptibility to lethal ventr...

BACKGROUND Although patients with Brugada syndrome (BS) are at risk of ventricular fibrillation (VF) and ensuing death, the action potential duration (APD) restitution properties of the right ventricular outflow tract (RVOT) in patients with BS remain undetermined. METHODS AND RESULTS Endocardial monophasic action potentials (MAPs) were obtained from 16 patients with BS and 17 control patient...

OBJECTIVES The purpose of this study was to test the hypothesis that the late Na current blocker ranolazine suppresses re-entrant and multifocal ventricular fibrillation (VF). BACKGROUND VF can be caused by either re-entrant or focal mechanism. METHODS Simultaneous voltage and intracellular Ca(+)² optical mapping of the left ventricular epicardial surface along with microelectrode recording...

BACKGROUND Laparoscopy-assisted distal gastrectomy (LADG) has been widely accepted for the treatment for early gastric cancer. Obesity is a rapidly growing epidemic, and the number of obese patients with gastric cancer is increasing, but the impact of visceral fat (VF) accumulation on laparoscopic gastric surgery remains unknown. The aim of the present study was to determine the impact of VF ac...

Rapid device aging in the nano era threatens system lifetime reliability, posing a major intrinsic threat to functionality. Traditional techniques overcome aging-induced slowdown, such as guardbanding are static and incur performance, power, area penalties. In manycore processor, system-level design abstraction offers dynamic opportunities through control of task-to-core mappings per-core opera...

The mechanisms behind the complex activation sequences during ventricular fibrillation (VF) have been the topic of intense research over many years. Experimental studies in animal models of VF, as well as clinical studies of human VF,1–8 have provided a wealth of data on the nature of electric activity in the fibrillating heart. Supplemented by computer simulations and a theoretical framework o...