Electrocardiograms in children with bronchial asthma

Electrocardiograms (ECG) from 124 asthmatic children were analysed with a view to defining the cardiac complications of bronchial asthma. Thirty-three percent of the patients had airway obstruction when the ECG were recorded; yet none had any significant cardiac arrhythmia. The P waves and P-R interval were each normal in all but one patient. One patient had right-ventricular hypertrophy (RVH), but in twenty-five others (20%) R waves suggestive of left-ventricular hypertrophy (LVH) were recorded in V5-6. The ST segment was elevated in seventeen patients (14%) and depressed in twelve others (10%), most of whom had suffered from severe asthma for 3 or more years. These findings confirm the rarity of RVH in bronchial asthma, and also imply that serious arrhythmias in asthmatic children should not be perfunctorily ascribed to airway obstruction; other causes of arrhythmia should be sought. We advise that beta-agonist bronchodilators should be cautiously prescribed to asthmatic Africans who may be rendered more susceptible to the arrhythmogenic tendency of such drugs by an underlying LVH.