[Estimation of the P wave and PQ interval dispersion in patients after the myocardial infarction]

Abstract

Aim: Because in patients with the recent myocardial infarction the noticeable differences in the P wave and PQ interval dispersion were observed in comparison to the control group, consisted of the healthy persons, it was an intresting problem to define the period of persistence of these visible changes on the electrocardiograms made in patients after the myocardial infarction. The aim of the study was to estimate the P wave and PQ interval dispersion in patients after the myocardial infarction in dependence on its location and applied fibrynolytical treatment.

Material and method: The investigations were conducted on 36 male and female patients in age 40 to 84 years (mean 56 +/- 10,8 years), divided into groups of patients suffering from the inferior myocardial infarction and anterior myocardial infarction. The estimation of P wave and PQ interval dispersion was made by two independent researches on the 12 offtake electrocardiogram, by using scanner and computer program Photo-Finish. There were analysed electrocardiograms made in 10th day, 6 weeks of recovery and successively in 3rd, 6th, and 12th month after the recovery. During the each investigation the echocardiography was made to state the dimension of the left atrium and the blood samples was taken for the measurement of the atrial natriuretic peptide concentration (ANP).

Conclusions: In all the investigated patients the P wave dispersion was significantly higher till 3 months after the myocardial infarction in comparison to the healthy control group, and the minimal and maximal lasting periods of both the P wave and PQ interval as well as the PQ interval dispersion hadn't significant difference comparing to the control group. In all the patients the P wave dispersion was significantly lower in the following examinations made in 3rd, 6th and 12th month of recovery comparing to the initial examination. ALL the examinations proved, that the maximal and minimal lasting period of PQ interval was significantly higher in the 6th week and 3rd, 6th and 12th month of recovery comparing to the examination made in the 10th day after the myocardial infarction. There were no differences between the P wave and the PQ interval dispersion in males and females, in the patients with the inferior myocardial infarction in comparison to the patients with the anterior myocardial infarction as well as in the patients treated fibrinolytically compared to these treated otherwise. It was no correlation between the left atrium dimensions and the P wave and PQ interval dispersion and the ANP concentration was positively correlated to the minimal lasting period of the P wave and the PQ interval in time 12 months after the myocardial infarction.