Sökning: "repolarization"

Visar resultat 1 - 5 av 23 avhandlingar innehållade ordet repolarization.

  1. 1. Traces of Repolarization Inhomogeneity in the ECG

    Författare :Milos Kesek; Anders Englund; Bertil Lindahl; Markku Mäkijärvi; Uppsala universitet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; Internal medicine; cardiology; repolarization; ECG; QT dispersion; nondipolar components; T-wave; principal component analysis; repolarization inhomogeneity; Invärtesmedicin; Internal medicine; Invärtesmedicin;

    Sammanfattning : Repolarization inhomogeneity is arrhythmogenic. QT dispersion (QTd) is an easily accessible ECG-variable, related to the repolarization and shown to carry prognostic information. It was originally thought to reflect repolarization inhomogeneity. Lately, arguments have been risen against this hypothesis. LÄS MER

  2. 2. Sequence and dispersion of repolarization of the right atrium: Implications of repolarization disturbance in atrial fibrillation

    Författare :Zhen Li; Kardiologi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Kardiovaskulära systemet; Cardiovascular system; electroanatomical mapping; monophasic action potential; atrial fibrillation; repolarization; dispersion;

    Sammanfattning : To explore the global sequence and dispersion of repolarization of the right atrium, monophasic action potentials (MAPs) were sequentially recorded from the right atrium using an electroanatomical mapping (CARTO) system in 10 healthy pigs and in 10 patients with (n=6) and without (n=4) paroxysmal atrial fibrillation (PAF) during sinus rhythm, or using two MAP recording catheters in 30 patients with or without PAF (n=15 each) during sinus rhythm, pacing, and programmed stimulation. The dispersion of activation time (AT), repolarization time (RT) and MAP duration (MAPd) were analyzed. LÄS MER

  3. 3. Cardiovascular regulation and vascular structure in prehypertension and coronary heart disease

    Författare :Anna Myredal; Göteborgs universitet; Göteborgs universitet; Gothenburg University; []
    Nyckelord :prehypertension; coronary heart disease; repolarization; baroreflex; intima thickness; CABG; non-dippers;

    Sammanfattning : The aim of this thesis was to characterize vascular structure and different aspects of cardiovascular regulation in otherwise healthy subjects with slightly elevated blood pressure and compare to healthy subjects with normotension and also investigate patients with established primary or secondary hypertension and coronary heart disease. Altered cardiac repolarization and arterial baroreflex function has been associated with adverse prognosis and increased risk for ventricular arrhythmias in patients with cardiovascular diseases. LÄS MER

  4. 4. Adaptation of ventricular repolarization to heart rate change in humans

    Författare :Karl-Jonas Axelsson; Göteborgs universitet; Göteborgs universitet; Gothenburg University; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; cardiac memory; hysteresis; long QT syndrome; QT adaptation; vectorcardiography; ventricular repolarization;

    Sammanfattning : Background: Life-threatening cardiac rhythm disturbances and sudden death are common manifestations of heart disease. Disturbances in electrical recovery (ventricular repolarization; VR) are important mechanisms behind ventricular arrhythmias, which often occur in relation to changes in heart rate (HR). LÄS MER

  5. 5. Global sequence and dispersion of ventricular repolarization: In vivo validation of non-invasive parameters using monophasic action potential mapping technique

    Författare :Yunlong Xia; Kardiologi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Kardiovaskulära systemet; Cardiovascular system; dispersion; electroanatomical mapping; T wave; epicardial pacing; Ventricular repolarization; monophasic action potential;

    Sammanfattning : The purposes are to validate the noninvasive parameters, QT interval, QT dispersion, Tpeak-Tend interval, and the activation recovery time (ART) for estimation of global dispersion of ventricular repolarization (DVR), and to investigate the changes of repolarization sequence and DVR by altered ventricular pacing sites. The material consisted of 12 patients (Study I) and two series healthy pigs with 10 in each (Studies II and III; Studies IV and V). LÄS MER