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Neurogenic orthostatic hypotension is due to interruption of the baroreceptor reflex. To optimize the pharmacological therapy in this clinical setting the lesion should be carefully pinpointed and the degree of denervation established. To this purpose 7 patients with autonomic failure underwent ambulatory intraarterial monitoring, which showed the reversal of the normal 24-hour blood pressure (BP) pattern. During daytime BP gradually rose from its lowest point early in the morning to a peak during late evening. No BP fall was observed during sleep. Tilting test, Valsalva maneuver, hyperventilation, cold pressor test, handgrip and pharmacological tests showed interruption of the efferent pathway of the reflex. The BP fall 60 seconds after assuming the orthostatic position significantly correlated with the BP response to the cold pressor test (r = 0.89; p less than 0.01), while it did not with the BP changes during hand grip and hyperventilation and with the orthostatic increase of heart rate. Therefore, the BP response to the cold pressor test seems the most reliable indicator of the degree of autonomic dysfunction in the lesions of the efferent pathway of the reflex.

In 6 normotensive and 14 borderline or mild hypertensive runners the intraarterial blood pressure (BP) changes determined by a maximal bicycle ergometric test and by an exhaustive run performed in outdoor conditions were recorded by means of the portable Oxford system. During running systolic BP attained higher values than during bicycle ergometry, while diastolic BP decreased during running and remained unchanged during ergometry. The highest BP values were recorded soon after starting running, then they progressively declined to increase once again during the final sprinting. Beat to beat analysis of the pressure tracings showed a peculiar pattern of the phasic waves throughout the run: continuous cyclic oscillations of pulse pressure were detected, as the variations of systolic blood pressure were not paralleled by those of the diastolic. The frequency of these rhythmic oscillations varied from 6-7 to 24-27/minute and was not related to respiration rate. The shape of these oscillations prompted us to investigate whether they were due to the "beat" phenomenon, that is to the combined effect of two waves with a nearly equal frequency. To verify this hypothesis 10 athletes during the run carried around the chest a Teruflex container filled with saline. The amplitude of the BP changes recorded in the container ranged from +/- 10 to +/- 50 mmHg. They were added by means of a computer to the BP tracing recorded during bicycle ergometry. The resultant wave was similar to that recorded in the radial artery during running.(ABSTRACT TRUNCATED AT 250 WORDS)

To study the mechanisms of the blood pressure changes during weight-lifting, three hypertensive and five normotensive body-builders underwent continuous intra-arterial monitoring. In two subjects (one normotensive and one hypertensive), intrathoracic and intra-abdominal pressures were also measured. Extremely high blood pressure elevations of up to 345/245 mmHg were observed during the lifts. Squatting caused the highest pressure rises and single-arm curls the lowest. Both the intrathoracic and the intra-abdominal pressures increased greatly during each lift and closely paralleled the changes in intra-arterial pressure. A close correlation was found between the blood pressure increase during the exercise and during a hand-grip test (r = 0.95, P less than 0.001). These results suggest that a pronounced increase in intra-thoracic and intra-abdominal pressures is a major determinant of the blood pressure elevations occurring during weight-lifting. The pressor reflex which accompanies static contractions and the individual baseline blood pressure levels also seem to affect the height of the pressure peaks.

Twenty-six test variables for psychological differentiation and cognitive abilities were factor analyzed with a View towards replication of certain factors of perceptual and conceptual differentiation and relating these factors the cognitive abilities. Eight factors were recovered and interpreted, including Form and Element Articulation, Flexibility of Closure, Speed of Closure, Perceptual Speed, and Conceptual Differentiation in Categorbation. Form Articulation appeared to be more related to Flexibility and Speed of Closure, while Element Articulation was more related to Conceptual Differentiation in Categorization. These findings are briefly discussed. .

Aim of the present study was to verify whether average blood pressure continuously recorded throughout the day correlates with the degree of target organ damage more closely than casual pressure in hypertensive patients. The study was conducted in 102 subjects with borderline, moderate and severe hypertension. Our results confirm a closer relationship between cardiovascular complications and recorder blood pressure than casual pressure possibly because the latter less perfectly reflects the patients usual pressures which are generally lower. However our results further demonstrate that blood pressure variability also contributes to the degree of target organ damage since for equal average day-time pressures a greater severity of cardiovascular complications was observed in patients with the highest blood pressure variability and the highest peaks of pressure. These findings should be carefully considered when evaluating the effect of antihypertensive drugs.

In 30 highly trained boys aged 10-14 the prevalence of ventricular ectopic beats and Q-T interval duration were studied. In trained boys ECG Holter monitoring showed a higher even though not significantly different prevalence of ventricular arrhythmias than in 30 age-matched untrained controls. Ventricular ectopy was on the contrary lower than in a group of 30 adult athletes. Q-T corrected (Q-Tc) interval in the trained boys was longer than in the sedentary controls (p less than 0.001), while it was as long as in the adult athletes. No correlation was found between the degree of severity of ventricular ectopic beats and Q-Tc interval duration, heart rate or echocardiographic dimensional and functional findings. The clinical and prognostic importance of complex ventricular arrhythmias detected in healthy athletes remains to be elucidated.

We have previously reported that blood pressure during running shows a peculiar pattern attributable to the beat phenomenon. To elucidate the mechanism behind this phenomenon in 10 amateur athletes, intra-arterial blood pressure was continuously recorded using the Oxford technique. During the run, each athlete carried on his chest a container filled with saline kept under pressure, connected to a second transducer. In the container, pressure waves ranging in amplitude from +/- 10 to +/- 62 mmHg were recorded. Their frequency was equal to that of the athletes' strides. When these waves were added by computer to the blood pressure tracing recorded during a bicycle ergometric test, the resultant harmonic proved to be similar to the tracing observed during running. The present results demonstrate that the running-induced blood pressure pattern is the sum of the accessory wave generated by the rhythmic aortic shocks produced by running locomotion and the normal sphygmic wave.

In 56 patients with borderline hypertension, casual blood pressure was compared with average daytime ambulatory blood pressure. The difference between these two values ranged from -20 to +40 mm Hg and was unrelated to spontaneous blood pressure variability, the blood pressure fall during sleep, and the peaks of pressure recorded during the day. Heart rate and a family history of hypertension were not predictive of the degree of difference between casual and average daytime recorder pressure. Target organ damage was present in 44% of the patients and was more closely correlated with recorder than with casual pressure.

To assess the role of dynamic stress test in hypertension three normotensive and ten borderline or mild hypertensive subjects were studied by means of the intraarterial Oxford technique. In all of the subjects the intraarterial monitoring lasted for 12 hours; during the recording a graded maximal bicycle exercise test was performed. Five patients considered hypertensive on the basis of their office blood pressure readings showed normal average 12-hour intraarterial recordings. Systolic blood pressure increase during ergometry ranged from 22 to 57 mmHg; exertional pressure readings were strictly related to average 12 hours intraarterial blood pressure (r = 0.92; p less than 0.001). No correlation was found between resting blood pressure and the exertional pressure taken with the auscultatory method. These data indicate that the level that blood pressure attains during ergometry primarily depends on the resting blood pressure values, and therefore do not justified the separation between normo and hyperreactive subjects as some authors have done. In conclusion, dynamic exercise may be a useful diagnostic test for hypertension but has no predictive value for either the development of high blood pressure or the progression from borderline to more severe forms of hypertension.

Short-term blood pressure variability has been studied extensively with monitoring techniques. To assess whether or not and to what extent average 24-hour blood pressure varies when repeatedly recorded, 12 mild to moderate hypertensive subjects underwent 3 non-invasive blood pressure monitorings at monthly intervals. When the average 24-hour blood pressure of the whole group was evaluated no substantial differences were found between the 3 recordings, even though slightly lower blood pressure values were recorded at the first monitoring. However, when the within-period comparison was studied in the single patients, remarkable discrepancies of up to 20.9/15.8 mmHg were detected. Systolic and diastolic blood pressure variations greater than or equal to 5 mmHg were recorded in 58% of the subjects. These differences were unrelated to the number of faulty readings. Casual blood pressure varied even to a greater extent between the first and the subsequent visits; no correlation was found between casual and 24-hour blood pressure variations. The results of the present study indicate that ambulatory blood pressure may vary even to a great extent when repeatedly recorded. This finding entails important clinical implications, as the evaluation of the hypertensive patient is usually made with a single blood pressure monitoring.