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PubMed · 1275839

Bradycardia induced by negative acceleration.

J A Kennealy·J S Kirkland·R E Sneider
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Abstract

Four volunteers were subjected to negative acceleration in a human centrifuge for the purpose of testing a standard lap belt. Three subjects developed a sinus bradycardia. The fourth developed a sinus arrest with a junctional rhythm at -2 G. With return to +1 G, the sinus mechanism recovered with a prolonged P-R interval. Within 2 h, the P-R interval returned to normal. Negative acceleration maneuvers, well within the capabilities of high-performance aircraft, can effect marked changes in the cardiac rhythm. This phenomenon appears to be vagally induced and is remarkably well tolerated.

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AccelerationAerospace MedicineBradycardiaHumansJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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J A Kennealy, J S Kirkland, R E Sneider. 1976. Bradycardia induced by negative acceleration.. https://pubmed.ncbi.nlm.nih.gov/1275839/

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