[Suprasystolic dP/dt max an additional parameter of contractile cardiac function obtained by cuff oscillometric tracings]. / Un paramètre additionnel de fonction ventriculaire gauche dérivé du profil oscillométrique artériel.

Technological evolution allowed to record high fidelity traces that--when analysed by complex mathematical systems--may provide extremely detailed and new information about all the factors involved in the determinism of pulse wave. Suprasystolic waves, i.e. those recorded immediately before systolic pressure, may be regarded as similar to aortic pressure waves evaluated during cardiac catheterization. Suprasystolic dP/dt max was calculated from the profile of pulse wave recorded by the DynaPulse, an automatic portable non-invasive oscillometric method to simultaneously measure BP and analyse arterial waveforms, in 10 normal healthy subjects (age 37 +/- 5) and 5 subjects with ischaemic dilatative cardiomyopathy (age 41 +/- 7) whose ejection fraction--invasively assessed--was < 40%. The 24 h dP/dt max curves were analysed by parametric and non parametric tests. We found a significant difference (p < 0.001) in the average 24-h dP/dt max between healthy subjects (471 +/- 36.7 mmHg/sec) and patients with impaired cardiac function (271 +/- 54.2 mmHg/sec). The average daytime and nighttime dP/dt max values showed significantly higher values in normal subject in comparison to patients with heart failure (daytime 7.23 h: 529 +/- 74 mmHg/s versus 227 +/- 64 mmHg/s, p < 0.001; nighttime: 572 +/- 82 mmHg/s versus 202 +/- 67 mmHg/s, p < 0.001). We also found a difference in the occurrence of acrophases, at similar blood pressure value, i.e. the highest dP/dt values occurred during the night in normal subject, the opposite in ischaemic patients. Furthermore, the dP/dt max correlates only with systolic blood pressure.

Early nocturnal blood pressure changes in diabetic autonomic neuropathy assessed by Fourier series.

The 24 h periodic pattern of blood pressure was studied in 44 patients with diabetes mellitus (14 type 1, 30 type 2; mean duration of disease 6.5 +/- 1.8 years) in good metabolic control but with abnormal cardiovascular reflex responses; of these 21 were normotensive and 23 hypertensive. All had abnormal responses to at least two out of four tests: deep breathing, lying to standing, Valsalva manoeuvre and postural hypotension. Two sex- and age-matched groups, consisting of 20 normotensive and 20 hypertensive diabetic patients without dysautonomia, were studied as controls. Each patient underwent ambulatory blood pressure monitoring for at least 24 h, using an auscultatory automatic device. Data were analysed using the sum of three periodic functions (Fourier partial sum). In the diabetic normotensive groups, the absolute blood pressure fell to its night-time minimum more rapidly, and increased to its morning maximum more slowly, in those with abnormal cardiovascular reflexes than in the controls (nightly blood pressure decrease -5.8/-4.7 vs. -3.8/-4.0 mmHg/h; increase 4.7/3.6 vs. 5.9/6.1 mmHg/h). The same behaviour was found in both hypertensive groups but the amplitude of the differences was more marked (blood pressure nocturnal decrease -7.7/-7.1 vs. -4.3/-3.9 mmHg/h; increase 3.2/2.1 vs. 5.8/4.3 mmHg/h). This analysis of 24 h ambulatory blood pressure data may be of value in diagnosis and evaluation of autonomic deficits.

Ambulatory blood pressure recording in diabetic patients with abnormal responses to cardiovascular autonomic function tests.

The aim of our study was to analyse the 24-h periodic pattern of blood pressure (BP) in diabetic patients with abnormal responses to cardiovascular reflexes, in order to evaluate the extent of the initial autonomic damage. We studied 44 patients with diabetes mellitus (14 insulin-dependent, 30 non-insulin-dependent; mean duration of disease 6.5 +/- 1.8 years) in good metabolic control (fasting glycaemia less than 140 mg/dl, postprandial glycaemia less than 180 mg/dl, fructosamine less than 285 mg/dl), divided into two subgroups, containing 21 normotensives (13 males and 8 females aged 28-72 years) and 23 hypertensives (13 males and 10 females aged 32-70 years) respectively. All patients showed abnormal responses to at least two out of four tests: deep breathing, lying to standing, Valsalva manoeuvre and postural hypotension. Two sex- and age-matched control groups were recruited, comprising 20 normotensive and 20 hypertensive diabetic patients without dysautonomia, respectively. The reference group consisted of 248 normotensives (135 males and 113 females, aged 18-76 years) and 212 mild-moderate hypertensives (130 males and 82 females, aged 27-66 years). Each patient underwent ambulatory BP monitoring for at least 24 h, using an auscultatory automatic device. Data concerning biological rhythms were analysed by means of periodic functions. We limited the Fourier partial sums to the first three harmonics.(ABSTRACT TRUNCATED AT 250 WORDS)

Noise stimulus in normal subjects: time-dependent blood pressure pattern assessment.

Environmental noise may have various effects on blood pressure. The aim of our study was to verify noise impact on blood pressure in normal young subjects, using the "white noise" stimulus. Thirty subjects (16 males and 14 females, median age 22 years) were studied. The presence of hypertension, hypertensive hereditibility and loss of acoustic acuity were criteria for exclusion. Noninvasive measurements of systolic and diastolic blood pressure at three-minute intervals were performed with an oscillometric system (Omega 1000, In Vivo Research), for each of four phases of the trial. After an initial rest phase (9 min) to avoid the patient's "alarm reaction," "white noise" with an intensity equal to 40, 100, and 40 adjusted decibels (dBa) was administered consecutively for 18 min (2nd phase), 9 min (3rd phase), and 18 min (4th phase), respectively. Preliminary analysis with standard statistical tools was not able to analyze the blood pressure patterns during the test. On the contrary, polygonal analysis, taking into account the "time-dependent" changes, showed that noise exposure (100 dBa) significantly increased systolic blood pressure in 22/30 subjects. However, systolic blood pressure rose only at the beginning of the 100 dBa exposure, indicating that stimulus changes rather than noise are key provoking factors in blood pressure increases.

Evaluation of the effect-duration of once-daily enalapril compared with once-daily captopril.

The extent and duration of the antihypertensive effect of enalapril and captopril, both given once daily, were evaluated in 12 mild-to-moderate essential hypertensives by 24-hour noninvasive blood pressure (BP) monitoring (Pressurometer IV-mod 1990-1991, Del Mar Avionics). Patients were randomized to a cross-over regimen either with enalapril, 10-20 mg, followed by captopril, 50-100 mg (first group), or with captopril followed by enalapril (second group). The dose was doubled if, at week 3 of each treatment, the diastolic BP remained at 90 mm Hg. Doubling of the 2 drugs was not required in 4 patients; in 7 patients the dose of both drugs was doubled; and in 1 patient the dose of only captopril was doubled. Two of the 7 patients who required doubling of both drugs were considered nonresponders to enalapril and captopril. The circadian rhythm was not altered by the treatments, and the drugs reduced BP mainly during the waking hours. However, the second peak of systolic BP in the late afternoon did not graphically appear to be modified by captopril administration. A periodic asymmetric model with 3 harmonics analysis carried out on 24-hour BP data justifies only the use of enalapril for once-daily administration.

Pressor effects from daily events and laboratory complex stimuli relating personality factors.

Our preliminary research has attempted to establish a series of methods to study the complex interactions occurring between pressor reactivity and personality profile. Ten untreated mild hypertensives (age 42.9 +/- 8) without damaged target organs were recruited from an outpatient hypertension center along with an equal number of normotensive volunteers (age 38.2 +/- 8.1). We performed a sequence of stressor types under laboratory conditions (sensory perceptual activities, psychomotor responses, and cognitive behavior) following an order ranging from inferior levels to superior levels of systemic integration. The subjects also underwent a 24-h automatic noninvasive blood pressure recording which took into account the situational reactivity. They filled in MMPI and STAI questionnaires before and after the stressor batteries. Only the sensory-perceptual test (Stroop color test modified), the arithmetic test, and the psychomotor test provoked a significant increase in blood pressure and, in the latter test, also a significant increase of the heart rate. The test batteries' mean differences were not significant between the two groups. Similarly, the answers to the trait-anxiety questionnaires did not allow us to make a substantial division between normotensive and hypertensive subjects. On the contrary, the situational anxiety questionnaires showed a significant difference in the score reading preceding and following a task performed by the hypertensive subjects. We observed significant differences for both systolic and diastolic 24-h blood pressure data in transition from a working situation to the sleeping period. However, there was not a significant difference in hypertensive blood pressure readings recorded during work and at home.(ABSTRACT TRUNCATED AT 250 WORDS)