Simultaneous unipolar and bipolar electrograms were recorded and compared from 49 pacemaker patients with bipolar endocardial electrodes. Average bipolar depolarization signal voltage equalled that of unipolar but showed greater variation. Bipolar and unipolar slew rates were equal in both mean and variance. The proximal pole voltage had little effect on the bipolar result in 8% of the cases, t...

The role of the amplitude, number, and duration of unipolar rectangular electric pulses in cell membrane electropermeabilization in vitro has been the subject of several studies. With respect to unipolar rectangular pulses, an improved efficiency has been reported for several modifications of the pulse shape: separate bipolar pulses, continuous bipolar waveforms, and sine-modulated pulses. In t...

THE 4 ORIGINAL PAPERS ARE 1. Hasselbalch BJ, Knorr U, Kessing LV. Cognitive impairment in the remitted state of unipolar depressive disorder: a systematic review. J Affect Disord 2010 Dec;134(1-3):20-31. 2. Hasselbalch BJ, Knorr U, Hasselbalch SG, Gade A, Kessing LV. The cumulative load of depressive illness is associated with cognitive function in the remitted state of unipolar depressive diso...

BACKGROUND Endocardial mapping is mandatory before radiofrequency catheter ablation (RFCA). Mapping can be performed with either unipolar or bipolar recordings. Impact of the recording technique used was studied in patients with and without structural heart disease using the 3D electroanatomic CARTO mapping system. METHODS AND RESULTS Patients (n=44; 16 males; age 43+/-16 years) referred for ...

BACKGROUND Localized sites of high frequency during atrial fibrillation (AF) are used as target sites to eliminate AF. Spectral analysis is used experimentally to determine these sites. The purpose of this study was to compare dominant frequencies (DF) with AF cycle length (AFCL) of unipolar and bipolar recordings. METHODS AND RESULTS Left and right atrial endocardial electrograms were record...

Background—Endocardial mapping is mandatory before radiofrequency catheter ablation (RFCA). Mapping can be performed with either unipolar or bipolar recordings. Impact of the recording technique used was studied in patients with and without structural heart disease using the 3D electroanatomic CARTO mapping system. Methods and Results—Patients (n 44; 16 males; age 43 16 years) referred for RFCA...

A model of one-dimensional action potential propagation was used to compare activation times and recovery times measured from simulated unipolar and bipolar electrograms with the activation and recovery times measured from simulated transmembrane action potentials. Theory predicts that the intrinsic deflection--the time of the maximum negative slope of the unipolar electrogram QRS complex--corr...

We have investigated the midinfrared unipolar photoluminescence in InAs/GaAs self-assembled quantum dots. Resonant emissions between confined levels are clearly observed at low temperature at around 10 mm wavelength. The unipolar emissions are polarized either in the layer plane or along the z growth axis of the quantum dots. The emissions are associated with hole transitions that involve the g...