Relationship between plasmatic concentrations of K, Na and Ca, and ECG from foals during postnatal phase.

The correlations between different electrocardiographic variables and plasma concentrations of K, Na and Ca ions were studied in foals of 1 to 14 days of age. The results obtained are only significant in neonate individuals of 1 day of age. Whilst the PQ segment and R wave duration showed a positive linear correlation (p less than or equal to 0.05) with plasma concentrations of Na and Ca ions respectively, the amplitude of the T wave showed a negative linear correlation (p less than or equal to 0.05) with the K ion. Moreover, the variability in duration of the QT and ST intervals can be explained by both Na (p less than or equal to 0.01 and p less than or equal to 0.05, respectively) and K (p less than or equal to 0.05 and p less than or equal to 0.01, respectively) plasma concentrations with which they show a positive linear correlation.

Evolution of the ECG from Spanish bred foals during the post natal stage.

A study of electrocardiograms recorded from foals during the first two weeks of life has been made in order to detect any changes of the cardiac activation and recuperation processes during this period. A stepwise discriminant analysis revealed significant differences between the first and second week of age, fundamentally on the basis of the T and P wave amplitudes which gave the lowest values at 14 days, and on the PQ segment duration that showed the highest values at the same age.