Different categories of psychological measures to varying extent are associated with characteristic patterns of coagulation and fibrinolysis activity. Associations between psychological factors and several coagulation and fibrinolysis variables related to atherosclerosis provide a plausible biobehavioral link to coronary artery disease.

Background-Phenylephrine bolus injection is an established technique to measure baroreflex sensitivity (BRS). This study quantified the relationship between the phenylephrine method and noninvasive measures of BRS and examined the effects of aging and hypertension on BRS. We also examined whether heart rate variability (HRV) provides as much information as does BRS.

In this study, we tested the validity of a new method designed to estimate baroreflex control of heart rate from spontaneous changes in systolic pressure and pulse interval. This method was compared with a conventional method of assessing baroreflex control through measuring reflex adjustments in pulse interval associated with pharmacological manipulations of blood pressure. The estimates of baroreflex control derived from the two methods were significantly correlated; however, only the estimate derived using pharmacological changes in pressure detected significant impairment of baroreflex control in patients with damage to baroafferents produced by radiation for oropharyngeal cancer. Analysis of spontaneous changes in pressure and pulse interval therefore provide a meaningful estimate of baroreflex control of heart rate that is, however, less sensitive than estimates obtained using pharmacological manipulations in pressure.