P-wave indices for risk assessment of atrial fibrillation in chagas disease

ABSTRACT

BACKGROUND: Studies analyzing atrial activation in electrocardiograms (ECG) usually highlight P-wave duration, P-wave dispersion, PR interval, P/PRi ratio, and atrial activation time (AAT). Although these indices can be predictors of atrial fibrillation (AF) development in different clinical contexts, there are no studies specifically looking at them in the context of Chagas disease (CD). OBJECTIVES: To evaluate the following electrocardiographic indices as predictors of AF in CD P-wave duration, AAT, P-wave dispersion, PR Interval, and P/PRi ratio. METHODS: This retrospective study examined the ECG records of CD patients who had been monitored for at least 10 years and examined the progression in five electrocardiographic indices over time in patients with and without atrial fibrillation. RESULTS: Of the 42 patients with CD included in the study, 13 experienced AF ("AF yes") and 29 did not ("AF no"). The electrocardiographic records analyzed were taken an average of 20 years apart (20.55±7.54). While the P/PRi ratio was not different between the two groups at the time of the first ECG, it decreased from 0.68±0.11 to 0.57±0.11 in the "AF yes" group, such that the P/PRi ratio was significantly lower in the "AF yes" group than the "AF no" group by the time of the second ECG (p=0.03). There were no statistically significant differences in the other parameters studied. CONCLUSIONS: In our study, only the P/PRi ratio was shown to predict the onset of paroxysmal AF, with lower values predicting the occurrence of this arrhythmia.