Improvement in cardiac performance by oral long-acting theophylline in chronic obstructive pulmonary disease.

Although oral theophylline is a widely used bronchodilator in chronic obstructive pulmonary disease (COPD), its effects upon cardiac performance have not been fully established. The effect of slow release oral theophylline upon right ventricular and left ventricular ejection fraction was evaluated using first-pass quantitative radionuclide angiocardiography in 15 patients with COPD. After 72 hours of therapy, oral theophylline significantly increased right ventricular ejection fraction (42% to 48%, p less than 0.005). In 7 of 10 patients with depressed baseline right ventricular performance, including two with cor pulmonale, right ventricular ejection fraction normalized (greater than or equal to 45%). After long-term therapy, an average of 16 weeks, right ventricular fraction also increased (43% to 48%, p less than 0.005). Left ventricular ejection fraction improved significantly from 64% to 68% (p less than 0.05) at 72 hours and from 61% to 65% (p less than 0.025) after long-term therapy. These data indicate that oral theophylline produces a sustained modest enhancement of resting biventricular performance in COPD.