A study of pulmonary artery pressure, electrocardiography, and mechanocardiography in thoracic scoliosis.

Cardiac catheterisation was carried out in 40 patients with thoracic scoliosis in order to measure the pulmonary artery pressure. Statistical correlations were calculated between these results and the electrocardiographic and mechanocardiographic findings determined on a separate occasion. The pulmonary artery pressure was normal in 72% of subjects. It was inversely correlated with arterial oxygen tension but not with the aetiology, severity, or age at onset of the scoliosis. The accuracy of electrocardiography and mechanocardiography in predicting the pulmonary artery pressure was assessed. The closet correlates were found to be a tall P wave in lead II or III and a prolonged interval between pulmonary valve closure and tricuspid valve opening.