Charakterystyka elektokardiograficzna załamka P u pacjentów z niepełnym blokiem pęczka Bachmanna i migotaniem przedsionków

Abstract

Introduction: The structural and functional changes in atrial myocardium create a substrate for atrial fibrillation. The pathophysiology include enlargement of the cavities and replacing the cardiomyocytes with connective tissue. That slows down the conduction velocity and creates focal conduction block zones and slow conduction areas promoting the re-entrant circuits. The described changes influence the duration and amplitude of the P wave in the ECG. Materials and methods: The study group consisted of 54 patients diagnosed with atrial fibrillation. There were 19 women and 35 men, aged 65.8+/-10.0 years. 22 patients had paroxysmal AF, in sinus rhythm during the examination and 32 had persistent AF, in whom the direct current cardioversion was performed in order to achieve sinus rhythm. In patients with persistent atrial fibrillation the P wave duration after the restoration the sinus rhythm was significantly longer in comparison to patients with paroxysmal atrial fibrillation (159.2+/-14.3 vs 171.2+/-16.6 ms, p=0.006). Results: The patients with persistent AF showed higher positive amplitude in lead V1 as well as higher negative amplitude than patients with paroxysmal AF: positive amplitude (0.053+/-0.023 vs 0.084+/-0.040 mV, p=0.002), negative amplitude (0.045+/-0.018vs 0.075+/-0.037 mV, p=0.001). Discusion: In conclusions: In patients with incomplete Bachmann’s bundle block and atrial fibrillation the duration of the P wave is prolonged, more in the persistent arrhythmia group. The P wave duration and morphology correlate with the interatrial conduction disturbances. The P wave morphology changes indicate the causal relationship of AF rather with interatrial conduction delay than with left atrial hypertrophy.