ment of ventricular fibrillation at the time of cardiac operations, and has proved successful at other times (McDonald et al., 1963). Lown et al. (1962b) have described the use of directcurrent shock both experimentally and in the treatment of patients with atrial and ventricular arrhythmias (Lown et al., 1962a). The use of direct current enables the shock to be applied at a precise moment in t...

Coronary spasm can occur in the presence or absence of coronary artery disease. We therefore determined the effect of preexisting coronary stenosis on the incidence of ventricular fibrillation during reperfusion after circumflex artery (CFX) occlusion. Twenty dogs underwent a 30-minute open-chest CFX occlusion. During reperfusion, CFX blood flow was restricted by a partial occluder. In dogs tha...

BACKGROUND It is still unknown whether a fast heart rate or an irregular ventricular response in atrial fibrillation causes tachycardiomyopathy. Reduction in the variability of RR intervals without an increase in heart rate might be an alternative treatment when antiarrhythmic drugs fail to control the irregularity accompanying atrial fibrillation. SUBJECTS AND METHODS Eight patients underwen...

Identifying patients at high risk for the occurrence of atrial fibrillation is one means by which subsequent thromboembolic complications may be prevented. Left atrial enlargement is associated with progression of atrial remodeling, which is a substrate for atrial fibrillation, but impaired atrial pump function is also another aspect of the remodeling. Our objective was to differentiate patient...

BACKGROUND Prognosis in patients with ventricular tachyarrhythmia without structural heart disease (primary electrical disease) has been described as excellent. However, prognosis may be less favourable in the subgroup surviving an episode of ventricular fibrillation. METHODS AND RESULTS We prospectively followed 19 consecutive patients (age, 13 to 66 years; mean age, 33 years) who had surviv...

A 70-year-old man with end-stage heart failure and a continuous-flow left ventricular assist device received repeated electrical discharges from his biventricular implantable cardiac defibrillator. Although the electrocardiogram demonstrated ventricular fibrillation, the patient was awake and in no distress. A focused transthoracic echocardiogram was performed to assess ventricular function rev...

Programming of antitachycardia pacing in implantable cardioverter-defibrillators (ICDs) has reduced inappropriate device shocks to terminate ventricular arrhythmia. This implies reductions in distress and pain for the patient and prolongs the useful life of the device. Arrhythmia detection and treatment with ICDs can be programmed according to the arrhythmia ventricular rate, discriminating bet...

BACKGROUND We considered the role of programmed ventricular stimulation in primary prevention of sudden cardiac death in an idiopathic dilated cardiomyopathy population. METHODS AND RESULTS One hundred fifty-eight patients with idiopathic dilated cardiomyopathy underwent programmed ventricular stimulation. Ventricular tachycardia/ventricular fibrillation was triggered in 44 patients (group I,...

The number of patients with atrial fibrillation and congestive heart failure has steadily increased in the United States. The presence of atrial fibrillation increases morbidity and mortality for patients with left ventricular dysfunction. The emergence of cardiac resynchronization therapy to improve symptoms and survival from congestive heart failure may provide benefits for those with atrial ...

We examined the electrophysiologic effects of verapamil in eight patients with the WolffParkinson-White syndrome. Verapamil shortened the antegrade effective refractory period of the accessory pathway in three patients and abbreviated the shortest cycle length with 1:1 conduction over the accessory pathway in two patients. More significantly, verapamil decreased the shortest RR interval between...