A double-blind study on the effects of piracetam upon perceptual and psychomotor performance at varied heart rates in patients treated with artificial pacemakers
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Pacemaker-patients have previously been found to have significantly impaired performance in tests of critical flicker fusion (CFF), two-choice reaction time (RT) and vernier visual acuity (KVAT) when the heart rate is reduced from 70 to 45 beats/min in sitting position.
Twelve patients treated with artificial pacemakers were given 1.6 g Piracetam per os three times daily for nine days and placebo for another nine days. The effects on performance were compared in CFF, RT and KVAT at heart rates of 70 and 45 beats/min in sitting position. With placebo, there were significant impairments in CFF and RT at 45 beats/min and a similar trend in KVAT. With Piracetam, there were significantly less impairments in CFF at 45 beats/min and similar trends in RT and KVAT. With Piracetam there were also significant increases in KVAT, irrespective of heart rate, compared with placebo.
With regard to the differences in circulatory dynamics between 70 and 45 beats/min, the results indicate that Piracetam had some protective effect against the influence of an assumed cerebral hypoxia at the lower rate or a cortical arousing effect, which counteracted the decrement in vigilance associated with the slow heart rate.
Key wordsPiracetam Perceptual and Psychomotor Performance Cardiac Pacing Heart Rate
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