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BACKGROUND Although patients with heart failure express elevated circulating levels of tumor necrosis factor-alpha (TNF-alpha) in their peripheral circulation, the structural and functional effects of circulating levels of pathophysiologically relevant concentrations of TNF-alpha on the heart are not known. METHODS AND RESULTS Osmotic infusion pumps(More)
BACKGROUND Radiofrequency ablation for atrial fibrillation is becoming widely practiced. METHODS AND RESULTS Two patients undergoing circumferential pulmonary vein ablation for atrial fibrillation in different centers developed symptoms compatible with endocarditis 3 to 5 days after the procedure. Their clinical condition deteriorated rapidly, and both(More)
Electrocardiography (ECG) is a critical source of information for a number of heart disorders. In arrhythmia studies and treatment, long-term observation is critical to determine the nature of the abnormality and its severity. However, even small body-wearable systems can impact a patient's everyday life and signals captured using such systems are prone to(More)
OBJECTIVES We sought to compare the cost-effectiveness of left atrial catheter ablation (LACA), amiodarone, and rate control therapy in the management of atrial fibrillation (AF). BACKGROUND Left atrial catheter ablation has been performed to eliminate AF, but its cost-effectiveness is unknown. METHODS We developed a decision-analytic model to evaluate(More)
BACKGROUND In an animal model, stretch was shown to induce myocardial tumor necrosis factor-alpha (TNF-alpha) expression. The purposes of this study were to determine whether the left ventricular (LV) volume overload that occurs in patients with chronic mitral regurgitation (MR) can induce myocardial and systemic TNF-alpha expression and whether there is a(More)
We present an 8-bit sub-ranging SAR ADC designed for bursty signals having long time periods with small code spread. A modified capacitive-DAC (CDAC) saves previous sample's MSB voltage and reuses it throughout subsequent conversions. This prevents unnecessary switching of large MSB capacitors as well as conversion cycles, reducing energy consumed in the(More)
—A syringe-implantable electrocardiography (ECG) monitoring system is proposed. The noise optimization and circuit techniques in the analog front-end (AFE) enable 31 nA current consumption while a minimum energy computation approach in the digital back-end reduces digital energy consumption by 40%. The proposed SoC is fabricated in 65 nm CMOS and consumes(More)
Left atrial global longitudinal strain predicts atrial fibrillation recurrence in patients with paroxysmal and persistent atrial fibrillation and preserved ejection fraction treated with first catheter ablation BACKGROunD: Atrial fibrillation (AF) frequently recurs after radiofrequency catheter ablation (CA).
INTRODUCTION The clinical utility of ventricular electrograms in comparison to atrial and ventricular electrograms in diagnosing the type of tachycardias recorded by an implantable defibrillator has not been addressed from the standpoint of a clinician's diagnostic accuracy and confidence in that diagnosis. METHODS Fifty-two tachycardia episodes recorded(More)
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