[The effect of sotalol hydrochloride therapy on atrial signal-averaged ECG in patients with paroxysmal atrial fibrillation].

The aim of this study was to evaluate of oral sotalol hydrochloride effects on atrial signal-averaged ECG (ASAECG) during time- and frequency-domain analysis in patients with paroxysmal atrial fibrillation (PAF) during ischemic heart disease (IHD). The study population of 27 was composed of 16 female and 11 male, mean age 56.1 +/- 8.4. The dose of oral sotalol was 160 mg/day for all days. Recording of ASAECG and 24-hours Holter monitoring were made at baseline, after 10 days and after 6 weeks of sotalol therapy. For ASAECG were calculated time-domain parameters: the root mean square voltage of the signals in the last 10, 20, 30 ms of the filtered P-wave (RMS 10, 20, 30) and total time duration of filtered P-wave (PWD) and time duration of P-wave for Frank leads X, Y, Z (XP, YP, ZP). During frequency-domain analysis of the terminal part of P-wave we calculated the following parameters in range from 40 Hz to 400 Hz: energy spectrum > -60 dB (A) and decibel drop at 40 Hz (Dd) in logarithmic scale and area ratio 20-50/0-20 Hz (Ar), magnitude ratio (MR1-7) in linear scale for a vector magnitude. Supraventriculat arrhythmias were estimated quantitatively and qualitatively during Holter monitoring. The following parameters were estimated in a case of PAF recording: time of manifestation, duration, number of PAF episodes per day, mean heart rate during PAF and subjective symptoms. Moreover, comparable analysis of the following parameters: dimension of left atrial, age, gender, time duration of IHD and PAF and wall motion disturbances-hypokinesis and also left ventricular ejection fraction, mitral regurgitation was done between patients with effective and no effective of antiarrhythmic therapy. Our observation have indicated that oral sotalol therapy are responsible for statistically significant decrease of total time duration of filtered P-wave (PWD) and time duration of P-wave for Frank leads X, Y, Z (XP, YP, ZP) and increase area ratio 20-50/0-20 Hz in patients with PAF during IHD. Moreover, comparable analysis of above-mentioned parameters have not showed statistically significant differences between examined patients with effective and lack of effective sotalol therapy.