Background—A therapeutic implication of the focal-source hypothesis of ventricular fibrillation (VF) is that VF can be terminated by focal ablation. We hypothesize that -adrenergic receptor blockade converts multiple-wavelet VF to focal-source VF and that this focal source is located near the papillary muscle (PM). Methods and Results—We used optical mapping techniques to study the effects of p...

We address the problem of improving variable-length-toxed-length codes (VF codes). A VF code is an encoding scheme that uses a xed-length code, and thus, one can easily access the compressed data. However, conventional VF codes usually have an inferior compression ratio to that of variable-length codes. Although a method proposed by T. Uemura et al. in 2010 achieves a good compression ratio com...

Immunotherapies for cancer are transforming patient care, but clinical responses vary considerably from patient to patient. Simple, inexpensive strategies to target treatment to likely responders could substantially improve efficacy while simultaneously reducing health care costs, but identification of reliable biomarkers has proven challenging. Previously, we found that pre-treatment serum IgM...

Ventricular tachycardia (VT) and ventricular fibrillation (VF) are potentially life-threatening forms of cardiac arrhythmia. Fast and accurate detection of these conditions can save lives. We used semantic mining to characterize VT and VF episodes by extracting three significant parameters (frequency, damping coefficient and input signal) from electrocardiogram (ECG) signal. This method was use...

OBJECTIVES We sought to gain more insight into the arrhythmogenic etiology of idiopathic ventricular fibrillation (VF) by assessing ventricular depolarization and repolarization properties by means of various electrocardiographic (ECG) techniques. BACKGROUND Idiopathic VF occurs in the absence of demonstrable structural heart disease. Abnormalities in ventricular depolarization or repolarizat...

INTRODUCTION Clinically in ventricular fibrillation (VF), ECG amplitude, and frequency decrease as ischemia progresses and predict defibrillation success. In vitro ECG amplitude declines without ischemia, independent of VF frequencies. This study examines the contribution of cellular electrical activity and global organization to ECG amplitude changes during VF. METHODS AND RESULTS Rabbit hea...

BACKGROUND A therapeutic implication of the focal-source hypothesis of ventricular fibrillation (VF) is that VF can be terminated by focal ablation. We hypothesize that beta-adrenergic receptor blockade converts multiple-wavelet VF to focal-source VF and that this focal source is located near the papillary muscle (PM). METHODS AND RESULTS We used optical mapping techniques to study the effect...

Placement of an implantable cardioverter-defibrillator (ICD) is the only powerful treatment modality for Brugada syndrome in patients presenting with ventricular fibrillation (VF). For those whose first presentation is an electrical storm, pharmacologic therapy is typically used to control VF followed by ICD implantation. We report an alternative approach whereby, before ICD implantation, emerg...

OBJECTIVES The purpose of this study was to determine if the defibrillation threshold (DFT) is lower during the first few cycles of ventricular fibrillation (VF) than after 10 s of VF and, if so, if the effect is caused by local or global factors. BACKGROUND The DFT may be low very early during VF because: (1) for the first few cycles VF arises from a localized region close to a defibrillatio...