title: Effects of air-flow limitation on the electrocardiogram in chronic obstructive pulmonary diseases (COPD).
abstract: Electrocardiographic studies have been carried out in one hundred and thirty patients of chronic obstructive pulmonary disease (COPD). The possible influence of air-flow limitation, alveolar air trapping, hypoxaemia and hypercapnia on the electrocardiographic findings indicative of right-sided cardiac involvement have been investigated. Thus, the findings: P greater than 2.5 mm, P-axis over +90 degrees, QRS axis over +90 degrees, RV6 less than or equal to 5mm and R/S ratio in V5 V6 less than or equal to 1.0 showed a significant negative correlation with FEV1/FVC ratio. The other features like Ta waves, negative P in AVL, S greater than 5 mm in depth in V5-6 and S1,S2,S3 pattern were observed to be less frequent and correlated weakly with the severity of the disease as judged by the lung function status. The reduction of FEV1/FVC was associated with increased residual volume (air trapping), hypoxaemia and hypercapnia. It is concluded that the ECG changes indicative of right-sided cardiac involvement may be produced by a combination of increased alveolar air trapping and blood gases derangement.
authors: V K
authors: VK
authors: Singh
authors: S K
authors: SK
authors: Jain
mesh_terms: D000328:Adult; D000368:Aged; D004562:Electrocardiography; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D012123:Pulmonary Ventilation / Q000502:physiology*; D014797:Vital Capacity / Q000502:physiology