This paper reports a patient with Wolff-Parkinson-White syndrome who presented with a tachycardia showing an unusual QRS morphology closely resembling that of a ventricular tachycardia. On reversal to a normal rhythm the electrocardiogram showed changes of a type A preexcitation, with subsequent conversion to a type B pattern. This phenomenon was observed on two separate occasions. Such convers...

This paper reports a patient with Wolff-Parkinson-White syndrome who presented with a tachycardia showing an unusual QRS morphology closely resembling that of a ventricular tachycardia. On reversal to a normal rhythm the electrocardiogram showed changes of a type A preexcitation, with subsequent conversion to a type B pattern. This phenomenon was observed on two separate occasions. Such convers...

Wolff-Parkinson-White (WPW) syndrome is a cardiac conduction disorder that presents with potentially life-threatening consequences. Wolff-Parkinson-White syndrome-induced dysrhythmias account for 20% of all supraventricular tachycardias that occur in the general population. Clinical presentations range from no symptoms to a sudden cardiac arrest. The risk of sudden death is always present with ...

Heart potentials were recorded from the entire chest surface in 42 patients suffering from Wolff-Parkinson-White syndrome. We were able to identify six types of surface maps, according to the location of the potential maximum and minimum during the delta wave. For each of these types we suggested the most likely location of the pre-excited region around the A-V rings (types 1 to 5) or in

WPW syndrome is a rare congenital heart disease due to an accessory pathway between the atrium and the ventricle. Its ECG pattern is characterized by a short PR interval, a delta wave, a wide QRS complex and an abnormal ventricular repolarisation. Patients are usually asymptomatic, or have frequent paroxysmal episodes of tachycardia. These tachycardias are supraventricular tachycardias related ...

We report on recent work, [1], concerning lower bounds on the localization length of eigenfunctions in the three-dimensional Anderson model at weak disorders, that uses an extension of methods developed by L. Erdös and H.-T. Yau. Our results are similar to those obtained by C. Shubin, W. Schlag and T. Wolff, [8], for dimensions one and two. Furthermore, we show that the macroscopic limit of the...

With the help of computer algebra, I devise an exact unitary transforma-tion for the Anderson impurity model which allows to kill the hybridizationterm in the slightly simplified case of zero chemical potential. Then I computeexplicitly the outcome of this transformation. This is a rigorous version of thewell known Schrieffer-Wolff transformation. It should be possible to tr...

Results of investigations of the O(4) spin model at finite temperature using anisotropic lattices are presented. In both the large N approximation and the numerical simulations using the Wolff cluster algorithm we find that the ratio of the symmetry restoration temperature TSR to the Higgs mass mH is independent of the anisotropy. We obtain a lower bound of 0.59±0.04 for the ratio, TSR/mH, at m...

Using a graphical representation based on the Wolff algorithm, the (classical) d-dimensional XY model and some related spin-systems are studied. It is proved that in d = 2, the predicted discontinuity in the spin-wave stiffness indeed occurs. Further, the critical properties of the spin-system are related to percolation properties of the graphical representation. In particular, a suitably defin...

data envelopment analysis (dea) is a mathematical programming-based approach for evaluates the relative efficiency of a set of dmus (decision making units). the relative efficiency of a dmu is the result of comparing the inputs and outputs of the dmu and those of other dmus in the pps (production possibility set). also, in data envelopment analysis various models have been developed in order to...