Verticalization of frontal P axis on electrocardiography in patients with acute exacerbation of chronic obstructive pulmonary disease and asthma / 中华全科医师杂志

ABSTRACT

Objective@#To investigate the clinical significance of verticalization of frontal P axis on electrocardiagraphy (ECG) in patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) and asthma.@*Methods@#Thirty five COPD patients and 20 asthma patients with acute exacerbation admitted in Jing′an District Central Hospital were enrolled and 20 health subjects served as a control group. The 12 lead ECG examination, pulmonary function test and high resolution CT (HRCT) scan of lung were performed. The P axis in ECG, pulmonary function and CT emphysema score were compared among three groups. The correlation of P axis verticalization with pulmonary function and CT emphysema score was analyzed.@*Results@#There were significant differences in P axis(F=24.36), FEV1/FVC(F=39.36), FEV1(F=28.82), FEV1%(F=30.64), FVC%(F=3.45), PEF%(F=13.22), RV/TLC(F=10.46) and total emphysema score (F=50.60) among the three groups (all P<0.01). P axis was positively correlated with age(r=0.229), total emphysema score(r=0.567), upper lung emphysema score(r=0.542), middle lung emphysema score(r=0.507), lower lung emphysema score(r=0.572)(all P<0.01), and negative correlation with body mass index(r=-0.491), cardiothoracic ratio (r=-0.396), FEV1/FVC(r=-0.609), FEV1(r=-0.389), FEV1%(r=-0.460), and PEF% (r=-0.419)(all P<0.01). Taking P axis>60 ° as cut-off value for screening COPD, the sensitivity was 0.933, specificity was 0.667, positive predictive value was 0.833 and negative predictive value was 0.857.@*Conclusion@#The verticalization of frontal P axis on ECG is significantly associated with obstructive ventilation disorder and CT emphysema score, which can be used as a preliminary screening index for COPD.