A patient with type A Wolff-Parkinson-White syndrome and prolonged interatrial conduction intervals developed atrial flutter during the course of an electrophysiological study. The atrial flutter blocked along the left-to-right conduction pathways in a Wenckebach pattern. The dissimilar atrial rhythms of right atrial tachycardia and left atrial flutter evolved as the interatrial block increased...

Aeroelastic flutter is a dangerous failure mode, and aircraft structural components are designed under a deterministic flutter margin. Meeting this safety factor may result in overly-conservative structures, however, an alternative approach incorporates uncertainties into the computational models, and imposes a maximum allowable flutter probability during the optimization process. This techniqu...

In anesthetized dogs, electrograms were recorded simultaneously from six atrial epicardial sites and a limb or esophageal lead in order to study the mechanism of atrial flutter induced electrically after an intercaval crush in comparison with atrial tachysystole induced by aeonitine. In the former, with limb lead records resembling classical human flutter in form and regularity, activation occu...

BACKGROUND Right atrial reentrant tachycardia resulting from lower loop reentry (LLR) around the inferior vena cava (IVC) has been described recently. However, all reported cases of LLR in the literature have negative flutter waves on the inferior surface ECG leads similar to that of counterclockwise typical atrial flutter around the tricuspid annulus (TA). Right atrial flutter with positive fl...

BACKGROUND In survivors of congenital heart surgery, intra-atrial reentrant tachycardia (IART) often develops. Previous reports have emphasized the atriotomy scar as the central barrier around which a reentrant circuit may rotate but have not systematically evaluated the atrial flutter isthmus in such patients. We sought to determine the role of the atrial flutter isthmus in supporting IART in ...

Analysis of an aeroelastic bridge system consisting of the fundamental vertical and torsional modes of vibration offers an expeditious assessment of bridge flutter performance. It also produces valuable insight into the multimode coupled bridge response to strong winds. This paper presents closed-form formulations for estimating the modal frequencies, damping ratios, and coupled motions of the ...

BACKGROUND Treadmill exercise and airway clearance with the Flutter® device have previously been shown to improve mucus clearance mechanisms in people with cystic fibrosis (CF) but have not been compared. It is therefore not known if treadmill exercise is an adequate form of airway clearance that could replace established airway clearance techniques, such as the Flutter®. The aim of this study ...

In order to correlate the electrical and mechanical events occurring in atrial flutter, three patients have been studied using the standard electrocardiogram, a computerprocessed vectorcardiogram, and reflected ultrasound recordings of valvular motion. Anterior motion of the mitral valve leaflet occurs in the region of the nadir of the atrial flutter wave in lead II of the electrocardiogram. In...

Typical atrial flutter, as referred to in this article, includes both the counterclockwise and the clockwise form of cavotricuspid isthmus-dependent right atrial flutter. The counterclockwise form is the most common and characterized by a stereotypical surface ECG pattern showing negative sawtooth flutter waves in II, III and aVF at a rate between 200–350 beats.min. This surface ECG morphology ...

This paper introduces an adaptive flutter suppression control algorithm which is based on the iterative estimate of the aeroelastic plant and design of the feedback controller. In this algorithm, the dual-Youla parametrization is implemented as an essential part to estimate the open loop aeroelastic model from the closed loop experiment. The advantage of utilizing the dual-Youla parametrization...