Med. Weter. 71 (3), 163-166, 2015
full text
| Noszczyk-Nowak A., Górszczyk A., Cepiel A., Pasławska U. |
| Analysis of repolarization parameters in healthy Great Danes. |
| The aim of the study was the analysis of the repolarization period in Great Dane dogs. Fifty-eight clinically healthy Great Danes (30 males, 28 females) between 1 and 9 years old (3.2±1.8 years old on average) were included in the study. A resting ECG with the use of limb (I, II, III, aVR, aVL, aVF) and precordial leads (V1, V2, V4) in the right lateral position was performed in each dog. Fifty-eight ECG curves were analyzed. The following parameters were assessed: rhythm, heart rate (HR), duration of the P wave, PQ duration interval, duration of QRS, and the R-wave amplitude. The repolarization period was assessed using 7 parameters: duration of the QT interval, adjusted duration of the QT interval (acc. to Fridericia formula), the T-wave amplitude, total repolarization time, duration of early and late (TpTe) repolarizations, and the Te/QT ratio. Statistical analysis was carried out by the U Mann-Whitney test and Spearman rank correlation, and a significance level of p<0.05 was adopted. All parameters used for the standard assessment of the ECG curve were within reference values for giant dog breeds. A higher average duration of QRS (66ms ± 4.9) was observed, but in no dog did it exceed 70 ms. No significant sex differences in the QT (203ms±19.1 vs 204.5ms±15.7) or QTcF (259.4ms±14.2 vs 263ms±13.7) intervals were observed. The T-wave amplitude was positive in 31 (53.44%), negative in 14 (24.14%), and biphase in 13 (22.42%) of the ECG recordings. A correlation of TpTe and TpTe/QT with the sex of the dogs was observed. Statistically significant differences in the values of TpTe and TpTe/QT were observed between males and females. Sex-related norms for these parameters were calculated (average±2SD). They were TpTe 18-42 ms, TpTe/QT 0.1-0.2 for females and TpTe 16- 54 ms, TpTe/QT 0.1-0.25 for males. No correlation of TpTe and TpTe/QT with age was observed. |
| Key words: repolarization period, Tpeak, Tend, T wave. |