... be partially related to the intense contraction of abdominal and expiratory muscles; later, the arterial hypotension related to the cough may contribute to the more sustained shortening of the R–R interval. 5. The cough test may be useful for the evaluation of cardiac parasympathetic integrity. autonomic...

...F. Bellavere; D. J. Ewing 1. The initial heart rate response to lying down was analysed in 18 younger (23–36 years) and 10 older (48–67 years) normal subjects, and consisted of an immediate shortening of the R—R interval reaching a maximum around the third or fourth beat after lying, followed...

... there was impairment of efferent vasoconstrictor function. 3. Changes in R—R interval were linearly related to changes in systolic blood pressure induced by higher levels of negative pressure. The slope of the relationship was taken as the sensitivity of the ‘high pressure’ arterial baroreflex; diabetic patients...