Techniques of Bedside Pacing

In temporary pacing the primary approach is transvenous--either percutaneous or via a cutdown in the jugular or brachial vein system. Tripolar and quadripolar pacemaker catheters which have been used for His bundle recordings are now obtainable as well as the bipolar variety. Among the latter is the floating catheter which may also be used as an intracavitary electrocardiogram. Doctor Furman of New York City has been extremely successful with this type in approximately 500 patients

Electrocardiographic Recognition of the Various Pacemaker Types and Dysfunction

This discussion deals with electrocardiographic interpretations of the various types of pacemakers as well as with their dysfunction which may be due to pulse generator failure, wire breakage, change in threshold, or polarization of the ventricle. Hemodynamic problems may also arise concerning placement of the pacemaker leads particularly in those patients who lack atrial contribution

On two-particle Anderson localization at low energies

We prove exponential spectral localization in a two-particle lattice Anderson model, with a short-range interaction and external random i.i.d. potential, at sufficiently low energies. The proof is based on the multi-particle multi-scale analysis developed earlier by Chulaevsky and Suhov (2009) in the case of high disorder. Our method applies to a larger class of random potentials than in Aizenman and Warzel (2009) where dynamical localization was proved with the help of the fractional moment method

On the Surface Pressure for the Edwards-Anderson Model

For the Edwards-Anderson model we introduce an integral representation for the surface pressure (per unit surface) in terms of a quenched moment of the bond-overlap on the surface. We find upper and lower bounds uniformly in the volume and show that at high temperature its value is strictly different from zero.Comment: Minor changes. To appear in Commun. Math. Phy

Wegner bounds for a two-particle tight binding model

We consider a quantum two-particle system on a d-dimensional lattice with interaction and in presence of an IID external potential. We establish Wegner-typer estimates for such a model. The main tool used is Stollmann's lemma

Mechanisms of A-V Block

Determination of the varieties of A-V block is predicated on the precise identification of the site(s) of conduction delay as prognosis, and therapy must follow on this basis. Further electrophysiologic and pharmacologic studies will undoubtedly reveal other mechanisms on the nature of A-V transmission

Graded cluster expansion for lattice systems

In this paper we develop a general theory which provides a unified treatment of two apparently different problems. The weak Gibbs property of measures arising from the application of Renormalization Group maps and the mixing properties of disordered lattice systems in the Griffiths' phase. We suppose that the system satisfies a mixing condition in a subset of the lattice whose complement is sparse enough namely, large regions are widely separated. We then show how it is possible to construct a convergent multi-scale cluster expansion

Simplicity of eigenvalues in the Anderson model

We give a simple, transparent, and intuitive proof that all eigenvalues of the Anderson model in the region of localization are simple

Clinical Significance of Exit Block

Clinical features of exit block were shown and its probable electrophysiological mechanisms discussed. Based on recent electrophysiological studies, it is emphasized that exit block is a result of depressed conduction surrounding the ectopic pacemaker