No abstract available.
Echocardiography ; Ventricular Fibrillation*

No abstract available.
Echocardiography ; Ventricular Fibrillation*

No abstract available.
Epilepsy ; Humans ; Seizures ; Ventricular Fibrillation

Profound hypothermia (15 degrees C) was induced in 36 mogrel dogs anesthetized with nitrous oxide-oxygen-d-tubocurarine. Prcpranolol (0.3 mg/kg) or MJ 1999(0.8 mg/kg) was administered intravenously 10 minutes prior to the start of cooling. Significant protection against ventricular fibrillation was provided by MJ 1999, but not by propranolol. With available evidence that hypothermia causes increased catecholamine release and that MJ 1999 is more specific in its beta-adrenergic blocking prcperties than propranolol, the authors findings suggest that ventricular fibrillation during hypothermia is due to beta-adrenergic hyperactivity.
Animals ; Dogs* ; Hypothermia* ; Propranolol* ; Sotalol* ; Ventricular Fibrillation*

Defibrillators, Implantable ; Electric Countershock ; Humans ; Ventricular Fibrillation

Child ; Electrocardiography ; Humans ; Male ; Ventricular Fibrillation ; physiopathology

The external defibrillator is an emergency instrument used very widely in clinics. It plays an important role in rescuing ventricle fibrillation (VF) patients. We have designed an external defibrillator using the truncated exponential biphasic waveform. The system consists of three parts: the ECG collection module, the control module and the defibrillator module. They are introduced respectively, listing the main problems and the methods to solve them. Some experiments have been done and the corresponding results are given.
Animals ; Defibrillators ; Equipment Design ; Swine ; Ventricular Fibrillation

The concept of J wave syndromes was first proposed in 2004 by Yan et al for a spectrum of electrocardiographic (ECG) manifestations of prominent J waves that are associated with a potential to predispose affected individuals to ventricular fibrillation (VF). Although the concept of J wave syndromes is widely used and accepted, there has been tremendous debate over the definition of J wave, its ionic and cellular basis and arrhythmogenic mechanism. In this review article, we attempted to discuss the history from which the concept of J wave syndromes (JWS) is evolved and current controversies in JWS.
Brugada Syndrome ; Death, Sudden, Cardiac ; Electrocardiography ; Ventricular Fibrillation

No abstract available.
Atrial Fibrillation* ; Humans ; Tachycardia, Ventricular* ; Wolff-Parkinson-White Syndrome*

PURPOSE: This study was designed to determine the compression rate and the compression/relaxation ratio to produce the optimal hemodynamic effect with simultaneous sterno-thoracic cardiopulmonary resuscitation (SST-CPR)and to investigate the mechanism for the blood flow generated by SST-CPR. METHODS: A canine model of ventricular fibrillation was used. Twelve mongrel dogs were divided into two groups. In the first six animals were resuscitated by using SST-CPR with the compression duration varied randomly at 2-minute intervals, 30%, 40%, and 50% of the CPR cycle, at a constant rate of 80/min. In the other six dogs, SST-CPR was performed with a randomly varied compression rate, 60, 80, 100, and 120/minute, at a 50:50 compression/relaxation ratio. RESULTS: During SST-CPR, increasing the compression relaxation ratio from 30:70 to 50:50 increased the end tidal CO2 from 10+/-2 mmHg to 15+/-3 mmHg. Increasing the compression rate from 60 to 100/minute tended to improve the carotid blood flow. CONCLUSION: The maximal hemodynamic effects with SSTCPR was generated when the compression rate was 100/minute and the compression/relaxation ratio was 50:50. A combination of the cardiac and the thoracic pump theories may be the mechanism for the blood flow produced by SST-CPR.
Animals ; Cardiopulmonary Resuscitation* ; Dogs ; Heart Arrest* ; Hemodynamics* ; Relaxation ; Ventricular Fibrillation