Sökning: "heart rate variability"

Visar resultat 16 - 20 av 119 avhandlingar innehållade orden heart rate variability.

  1. 16. Autonomic cardiac control in patients with epilepsy : spectral analysis of heart rate variability

    Författare :Håkan Persson; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :SUDEP; autonomic nervous system; heart rate variability; epilepsy; carbamazepine; epilepsy surgery;

    Sammanfattning : The heart is affected by the central nervous system via sympathetic and para-sympathetic efferents from autonomic centres in the brain stem. By assessing the beat to beat variation of the RR-intervals of the heart, i.e. the heart rate variability (HRV) it is possible to separately analyse sympathetic and parasympathetic effects on the heart. LÄS MER

  3. 17. Beat-to-beat variability of QRS amplitude and heart rate in ischemic heart disease : diagnostic potentials

    Författare :Inger Hagerman; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :autonomic blockade; beat-to-beat variability; chaos; coronary arterydisease; correlation dimension; dobutamine; ECG; electrical heterogeneity; fractal dimension; heart rate variability; Lyapunov exponent; nonlinear; QRSvariance; surrogate data;

    Sammanfattning : The diagnostic potential of beat-to-beat QRS amplitude variability in patients with coronary artery disease (CAD) was evaluated with variance ECG and compared to exercise stress test and myocardial scintigraphy (SPECT). Two high prevalence populations of 199 and 166 patients each were investigated. LÄS MER

  4. 18. Anticoagulation treatment in patients with a mechanical heart valve

    Författare :Bartosz Grzymala-Lubanski; Anders Själander; Peter J. Svensson; David Bergqvist; Umeå universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Mechanical heart valve; anticoagulation; warfarin; Time in Therapeutic Range TTR ; INR variability;

    Sammanfattning : BackgroundEvery year about 2,500 patients in Sweden undergo surgery for heart valve disease, primarily in the aortic valve.  In contrast to the mitral valve, which can be repaired in 70% of the cases, the aortic valve is normally replaced by a mechanical or biological prosthesis. LÄS MER

  5. 19. Signal Modeling and Detection in Nephrologic and Cardiac Applications

    Författare :Kristian Solem; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Heart rate turbulence HRT ; Heart rate variability HRV ; Electrocardiogram ECG ; Pulse oximetry.; Biomedical signal processing; Intradialytic hypotension; Hemodialysis; Ectopic beats;

    Sammanfattning : This doctoral thesis is comprised of five parts in the field of biomedical signal processing with focus on methods for use in hemodialysis as well as in cardiac applications. The problem of predicting hypotension is the main concern in the parts were data from patients undergoing hemodialysis are used. LÄS MER

  7. 20. Variability of blood pressure and heart rate in borderline and mild hypertension : With special reference to spectral analysis

    Författare :Reijo Takalo; Uppsala universitet; []
    Nyckelord :Medical sciences; hypertension; blood pressure; ambulatory monitoring; power spectrum analysis; pulsecontour method; systemic hemodynamics; MEDICIN OCH VÅRD; MEDICINE; MEDICIN; Clinical Physiology; klinisk fysiologi;

    Sammanfattning : The aim of this thesis was to study whether blood pressure (BP) or heart rate (HR) variability in borderline (BHT) and hypertensive (HT) subjects differs from that in normotensive (NT) subjects, and whether indices for BP and HR variability can be used in risk stratification for future hypertension. The study groups consisted of 35 NT, 29 BHT, and 34 HT middle-aged men. LÄS MER