Martymjanova L.A. Spectral analysis of heart rate variability of atrial fi- brillation patients. – Manuscript. Thesis for a candidate’s degree of medical sciences with specialty 14.01.11 – cardiology. – M.D.Strazhesco Institute of Cardiology, Academy of Medical Science of Ukraine, Kiev, 2003. The dissertation is devotes to the definition of possibility and expediency of using technologies of heart rate variability (HRV) in clinical evalu- ation of persistent and constant atrial fibrillation (AF) and determination on this basis diagnostic and prognostic criteria of its therapy efficiency. The dependence of characteristics of HRV from the age, clinical features of AF. especially concerning the AF forms, the weight degree of heart failure and the sire of ejection fraction left ventricular was determined. The suf- ficiently high degree of stability time-domain and spectral analysis of HRV was sawed. The types of heart rate depended adaptation reactions in acute pharmacological test with propranolol and without it. Diagnostic and prog- nostic criteria of therapy efficiency of persistent and constant AF are de- fined on the basis of clinical features and measurements of HRV, discrimi- nates functions are basis, which allow to prognoses the AF therapy effici- ency. Investigations are confirms the keeping of neurohumoral influence on the cardiovascular system in AF and allow to recommends to use the technology of HRV in studding and clinical management of AF. Key words: atrial fibrillation, heart rate variability, stability of para- meters HRV, functional test, criteria of therapy efficiency.