title: Improved working capacity following theophylline infusion in patients with ischaemic heart disease.
abstract: The effect of theophylline on the working capacity of patients with ischaemic heart disease was evaluated in a double-blind, randomized cross-over study. Eight patients, receiving no medication, with stable effort-provoked angina pectoris and typical exercise-induced ST depressions were studied. Following intravenous administration of theophylline or placebo, the patients did a supine leg exercise limited by intolerable chest pain. The workload was continuously increased by 10 W/min. Following theophylline treatment the workload at the onset of chest pain increased from 71 +/- 9 to 114 +/- 14 W (P less than 0.002). The ST depression was less pronounced following theophylline at submaximal exercise (-0.01 +/- 0.00 vs. -0.09 +/- 0.02 mV, P less than 0.005, at 70 W). The maximum tolerable workload increased from 129 +/- 15 after placebo infusion to 153 +/- 12 W after theophylline infusion P less than 0.01). It is speculated that this beneficial effect of the adenosine receptor antagonist theophylline may possibly be due to inhibition of a pathophysiological coronary steal induced by elevated levels of adenosine during ischaemia.
authors.affiliation: Department of Clinical Physiology, Huddinge University Hospital, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Edlund
authors.forename: R
authors.initials: R
authors.lastname: Söderberg
authors.forename: P
authors.initials: P
authors.lastname: Henriksson
mesh_terms: D000368:Aged; D000628:Aminophylline / Q000008:administration & dosage / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D003327:Coronary Disease / Q000188:drug therapy / Q000503:physiopathology*; D004311:Double-Blind Method; D004562:Electrocardiography; D005080:Exercise Test; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D010807:Physical Endurance / Q000187:drug effects*; D011897:Random Allocation
chemical_list: D000628:Aminophylline