The recently described "Sunct" syndrome is a rare picture of unilateral, shortlasting headache attacks accompanied by autonomic phenomena (conjunctival injection, tearing, etc.) on the symptomatic side. Heart rate and blood pressure were monitored in two elderly "Sunct" patients during and outside headache attacks. An ultrasound Doppler servo method was used for the non-invasive, continuous, beat-to-beat determination of instantaneous arterial blood pressure. In a third patient, systolic and diastolic blood pressure, both outside and during pain paroxysms, were assessed using the standard Korotkoff method. Heart rate was found to be significantly decreased during pain paroxysms. Systolic blood pressure was observed to be significantly increased during attacks, when compared with the inter-attack period, while a less consistent pattern was observed for diastolic blood pressure. Some of the changes in the cardiovascular system seemed to start prior to pain onset. Therefore, it seems unlikely that these changes were caused by pain activation of the sympathetic nervous system or the oculocardiac reflex.

Beta-blockers are among the most widely used antihypertensive drugs. They differ from each other in regard to several factors such as: beta-agonist activity, beta 1-selectivity and solubility. Aim of this work was to evaluate the influence of obesity on the kinetics and the antihypertensive effect of two Beta-blockers with different solubility such as: the water-soluble, atenolol and the liposoluble, metoprolol. The study was carried out according to an open randomized cross-over design. Eight obese hypertensive patients, after a two week washout period, were randomly allocated to a four week treatment. After a two week intermediate washout period, each patient switched to the other treatment for an additional four week period. On the first and the last day of each treatment the subjects were hospitalized to collect blood samples for the assay of the two drugs and to measure cardiovascular parameters. Obesity does not exert any effect on the kinetics of the water-soluble beta-blocker, atenolol, while markedly interferes with that of the liposoluble, without any apparent influence on its anti-hypertensive effect. These findings extend to obese hypertensives the concept that the plasma concentrations of beta-blocking agents are not reliable predictors of their therapeutic effect.

The reproducibility of the cold pressor test was studied in healthy subjects. A non-invasive method was utilized for estimating beat-to-beat arterial blood pressure (BP) and heart rate (HR). The study population of 17 healthy volunteers consisted of two groups. In the first group (Group 1, n = 11), a 1-min test was performed three times during the same day. In the second group (Group 2, n = 6), a 2-min test was repeated at the same time of the day on three consecutive days. In both groups, the test response was defined as the 46- to 60-s mean, minus the prestimulus 15 s baseline mean. In Group 1, a fair test-retest reliability was observed for the systolic BP response (intraclass correlation coefficient R = 0.57). Large intraindividual HR and diastolic BP variabilities were found. The intraindividual testretest difference in Group 1 ranged from -8 to 11 beats/min (SD = 4.3, R = 0.49) for the HR, from -16 to 13 mmHg (SD = 6.3) for systolic BP, and form -21 to 20 mmHg (SD = 9.7, R = 0.23) for diastolic BP. Even larger variability was observed when the test was repeated on different days (Group 2). Thus, the maxim that the response pattern to the cold pressor test is fairly constant for each individual may not be true. It does not seem to be advisable to use the results from one solitary cold pressor test. The use of replicated measurements and large sample sizes in comparative studies to compensate for the low to moderate reliability of the cold pressor test is recommended.

Cardiovascular responses to sympathetic stimulation may be altered in the early phases of life of subjects with a family history of hypertension.

A link between the activity of the adrenergic nervous system and left ventricular hypertrophy has frequently been found in hypertensives. In 16 patients with untreated primary hypertension of mild to moderate degree, we have evaluated the possible correlations between echocardiographic left ventricular mass (LVMe) and sympathetic nervous system activity, using pressor response to exogenous noradrenaline infusion, measurement of 24-h catecholamine urinary excretion and pressure response to ergometric exercise. Pressor response to noradrenaline infusion was significantly related to echocardiographic measures of left ventricular hypertrophy (correlation coefficients were: -0.60 for LVMe; -0.51 for septal thickness (ST); -0.51 for posterior wall thickness). Left ventricular mass was also related to systolic blood pressure measured during ergometric exercise (correlation coefficients were: 0.52 with LVM index, 0.51 with LVMe and 0.61 with ST). Arterial wall hypertrophy has been identified as being responsible for the vascular hyperreactivity in hypertension. A likely explanation of our findings is that the degree of left ventricular hypertrophy is associated with the degree of structural alterations of the resistance vessels and that the vascular impairment is responsible for the increased pressure response to noradrenaline.