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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.

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.

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)