Haemodynamic effects of sulphinpyrazone on exercise responses in normal subjects

The effects of sulphinpyrazone on heart-rate and blood-pressure responses to exercise were assessed in 15 normal volunteers by a randomised double-blind crossover technique. Submaximal exercise tests were performed 1 and 2 hours after either sulphinpyrazone (SPZ) 200 mg orally or placebo. Heart-rate and blood-pressure responses were unchanged at rest and during exercise 1 hour after SPZ but after 2 hours there was a significant fall in the product of heart-rate and blood-pressure during exercise (peak 35.8 +/- 1.5 x 10(-3) mmHg beats/min, placebo: 33.0 +/- 1.3 x 10(-3) sulphinpyrazone, p < 0.005) and for the first 2 minutes of recovery. This was mainly due to a decreased exercise-induced rise in systolic blood-pressure with lesser effects on heart-rate. This haemodynamic effect of SPZ has a potentially protective oxygen-sparing effect on the normal myocardium during exercise and may explain its apparent benefit in reducing sudden cardiac death after myocardial infarction.