Analýza vlivu transformačních metod na QRS komplex EKG záznamů na vektorkardiografické průběhy

Abstract

The main objective of this bachelor’s thesis is to compare the accuracy of selected transformation methods and to assess their impact on the morphology of the QRS complex. The analysis was performed using the PTB database, which includes 80 recordings from healthy subjects and 366 recordings from patients with myocardial infarction. The study focuses on five transformation methods: the Kors method, the inverse Dower transformation, QLSV, PLSV, and the quasi-orthogonal transformation. The accuracy of individual methods was evaluated using the mean squared error. Statistical comparison of the transformation methods was carried out using the Kruskal–Wallis test followed by post hoc analysis. Based on the statistical results, the Kors transformation method was identified as one of the most accurate methods. In lead Y, for healthy subjects, the inverse Dower transformation performs better when analyzing the QRS segment, whereas for the entire signal, the PLSV method achieves better results. In patients with myocardial infarction, a notable difference was observed particularly in lead Z, where the QLSV transformation proved to be the most accurate. The lowest accuracy, both for healthy subjects and myocardial infarction patients, was consistently achieved by the quasi-orthogonal transformation.