The focal source hypothesis of ventricular fibrillation (VF) posits that rapid activation from a focal source, rather than action potential duration (APD) restitution properties, is responsible for the maintenance of VF. We injected aconitine (100 microg) into normal isolated perfused swine right ventricles (RVs) stained with 4-[beta-[2-(di-n-butylamino)-6-naphthyl]vinyl]pyridinium (di-4-ANEPPS...

OBJECTIVES The goal of this analysis was to evaluate the association of impaired Thrombolysis In Myocardial Infarction myocardial perfusion grade (TMPG) with sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). BACKGROUND Impaired TMPG after successful restoration of epicardial flow among patients treated with fibrinolytic therapy for ST-segment elevation myocardial infarc...

BACKGROUND Implantable cardioverter defibrillator (ICD) is an effective treatment for secondary prevention of ventricular tachycardia/ventricular fibrillation (VT/VF). Left ventricular (LV) remodeling may develop before ICD implant and over time. However, it remains unclear how LV remodeling affects subsequent risk for recurrence VT/VF in ICD recipients under optimal medical therapy. METHODS ...

BACKGROUND After upper-limit-of-vulnerability (ULV) shocks of the same strength and coupling interval (CI) during the T wave, (1) the epicardial activation pattern (EAP) for the first postshock cycle is indistinguishable between shocks that do (VF) and do not (NoVF) induce ventricular fibrillation (VF) and (2) >/=3 cycles in rapid succession always occur during VF but not during NoVF episodes. ...

Background—T-wave alternans (TWA) increases before ventricular tachycardia (VT) or fibrillation (VF), suggesting that it may warn of VT/VF in implantable cardioverter-defibrillator patients. Recently, we described a method for measuring alternans and nonalternans variability (TWA/V) from electrograms (EGMs) stored in implantable cardioverterdefibrillators before VT/VF. The goal of this prospect...

BACKGROUND The purposes of the present investigation were 1) to track the incidence of primary ventricular fibrillation (VF) in the control and lidocaine-treated groups in the randomized control trials (RCTs) of lidocaine prophylaxis against primary VF in acute myocardial infarction, with particular emphasis on the time frame of the randomized trial, and 2) to estimate the number of patients wh...

This dissertation discusses the theory of single-amplifier biquadratic filters (SABs) and their implementation as CMOS video-frequency filters. It shows that building filters as cascades of single-amplifier biquadratic MOSFET–C sections is a viable alternative to using biquadratic Gm–C filter sections. The advantage of MOSFET–C SABs is that they typically use less chip area than a Gm–C filter w...

The velocity function (VF) of galaxies is analogous to the luminosity function (LF), but a more direct tool for comparing observations and theory. The 2MASS LF is calculated here for a local sample of 4000 galaxies, and the VF is derived from a 1000 galaxy subsample drawn from it. The observed VF follows a Schechter functional form. All current analytical, semi-analytical, and numerical galaxy ...

any experimental and clinical studies on the mechanisms of ventricular fibrillation (VF) have been performed over the past 10 decades. The underlying mechanisms of VF have been discussed from different points of view: initiation and maintenance. It is beyond question that reentry, triggered activity or automaticity initiates VF, but the mechanism of its maintenance is not fully determined. Alth...