Modeling of arterial and cardiopulmonary baroreflex control of heart rate. Desai, Tushar H., Jerry C. Collins, Marie Snell, Rogelio Mosqueda -Garcia. Departments of Biomedical Engineering, Medicine, and Pharmacology, Vanderbilt University, Nashville, Tennessee, 37232-2195
APStracts 3:0550H, 1996.
We evaluated in 13 subjects (27+/-6 yr; 7 males, 6 females) R-R interval changes as a function of blood pressure changes at the carotid sinus and aortic arch and central venous pressure changes at the cardiopulmonary receptors. Neck chamber pressure and suction were used to change pressure at the carotid sinus, while lower body negative pressure, phenylephrine infusion, and nitroprusside infusion were used to change pressure at the carotid sinus ( CSP), aortic arch ( AAP), and cardiopulmonary receptors ( CPP). Random effects regression analysis showed a significant linear relationship of R-R interval = -1.75 + 1.64 CSP + 15.40 AAP + 29.02 CPP + error and the correlation (r) between observed and predicted R-R interval was 0.82 (p<0.00001). Sixty-seven percent of the R-R interval variability observed in the study is explained by the model. AAP accounts for approximately 63%, CSP for 14% and CPP for 23% of explained changes in R-R interval.

Received 17 November 1995; accepted in final form 8 November
1996.
APS Manuscript Number H1081-5.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996