Comparison of serial electrocardiographic and vectorcardiographic changes during recovery from status asthmaticus.

Serial electrocardiographs (ECG) and vectorcardiographs (VCG) have been performed on 10 patients admitted to hospital in status asthmaticus on 12 separate occasions. The VCG was more efficient than the ECG in the detection of right atrial and ventricular enlargement. Both investigations were equally reliable in recording changes in frontal plane P wave axis. The mean frontal plane P wave axis fell from +60 degrees (range +35 degrees to +90 degrees) on the day of admission to +43 degrees (range +30 degrees to +60 degrees) at the time of discharge. The mean FEV1 expressed as a percentage of predicted values increased from 48% (range 25% to 81%) to 87% (range 44% to 123%). In direct contrast to previous studies the presence of an abnormally vertical frontal plane P wave axis (> 60 degrees) was related to the severity of airway obstruction (p < 0.01).