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The aim of this study was to assess the influence of antihypertensive agents on arterial wave reflections (AWR) and carotid pulse pressure (PP) in humans. Twenty patients with hypertension (predominantly systolic) were studied. After one month of placebo therapy they were randomly assigned to atenolol (At) 50 mg/day or to nitrendipine (Ni) 40 mg/day. Carotid pressure waveform was recorded noninvasively by applanation tonometry using a Millar micromanometer-tipped probe. Arterial wave reflections were quantified as the ratio of the height of the late systolic peak (delta P) to the total height of carotid pulse pressure wave as an augmentation index (delta P/PP). Travel time of the reflected wave (delta tp) was timed from the foot of the pressure wave to the foot of the late systolic peak. Atenolol and Ni were equally effective in reducing sphygmomanometric brachial artery blood pressure (BP). Whereas At (p < 0.05) and Ni (p < 0.01) reduced the carotid PP, Ni (p < 0.01) but not At significantly reduced delta P/PP. Both agents increased the delta tp (p < 0.01) and decreased aortic PWV (p < 0.01). Nitrendipine was associated with a decrease in left ventricular ejection time (LVET) (p < 0.01), while At increased heart period (p < 0.01) and LVET. The LVET/delta tp ratio decreased after Ni (from 3.25 +/- 0.77 to 2.42 +/- 0.73; p < 0.01) but did not change after At. The study shows, that for the same effect on peripheral BP, Ni has a more pronounced effect on pressure wave in central arteries, resulting from an improvement in the timing between the ventricular ejection and AWRs.

Aim: The aim of this study was to assess the effect of body height on arterial wave reflections and the carotid pulse pressure contour in humans., Methods: In 85 men, the carotid pulse wave and arterial wave reflections were determined from the common carotid artery pulse contour as recorded by applanation tonometry using a Millar micromanometer-tipped probe. The arterial wave reflection was calculated as the ratio of the height of the late systolic peak to the total height of the carotid pulse wave. The reflected wave was timed from the foot of the pressure wave to the foot of the late systolic peak., Results: Multiple regression analysis showed that body height and aortic pulse wave velocity were the principal determinants of travel time of the reflected wave and of arterial wave reflections (P < 0.0001), short stature being associated with a short travel time and increased reflections (P < 0.0001)., Conclusions: Body height is a determinant of arterial wave reflections and peak systolic blood pressure in humans.

The relationship between the presence of arterial calcinosis and the antihypertensive response to calcium blockers was studied in 40 hypertensive patients with end-stage renal failure (ESRF) on chronic hemodialysis, before and during 16 weeks after administration of nitrendipine in monotherapy. In a double-blind, placebo-randomized study, nitrendipine reduced systolic blood pressure regardless of the presence or absence of arterial calcifications. The antihypertensive effects were significantly more pronounced in subjects with aortic calcium deposits in comparison with patients without clinical signs of arteriosclerosis (p less than 0.01). Diastolic blood pressure was significantly reduced only in patients with aortic calcifications, and remained unchanged in subjects with noncalcified aorta. Aortic pulse wave velocity decreased significantly in patients with aortic calcifications (p less than 0.001), but remained unaffected in patients with noncalcified vessels. Multivariate regression analysis showed that antihypertensive action of nitrendipine was correlated with the presence of aortic calcium deposits independently of age or baseline blood pressure levels. The results of the present study indicate that an overt arteriosclerosis as demonstrated by the presence of aortic calcifications on abdominal radiographs is a good indication for use of dihydropiridines in patients with ESRF.

We studied the influence of parathyroid gland activity on cardiovascular response to dihydropyridines (nicardipine (NIC), 80 mg/day for 4 weeks) in 20 hypertensive patients with end-stage renal failure (ESRF). Before the treatment hyperparathyroidism (HPTH) was estimated on the basis of serum parathormone (PTH), and bone histomorphometry (osteoclastic resorption surfaces (ORS), and number of osteoclasts (NO]. NIC induced a significant decrease in systolic (SAP) and diastolic (DAP) arterial blood pressure, but did not significantly change the heart rate (HR) or the SAP X HR (myocardial oxygen consumption estimate). Changes in SAP and DAP were correlated to baseline serum PTH (P less than .001), to ORS (P less than .01) and to NO (P less than .01). Furthermore, a significant decrease in blood pressure was observed only in patients with histological signs of hyperparathyroidism (ORS greater than 1%). In this subset of patients NIC induced a significant decrease in SAP X HR (P less than .02) which was correlated to PTH and histomorphometric indexes of HPTH (P less than .01). The results of the present study show that blood pressure response to dihydropyridines in ESRF is associated with parathyroid activity as judged from serum PTH and bone histomorphometry.

Pulse wave velocity (PWV) was measured in the aorta, right leg and arm of 90 control subjects (CS) and 92 hemodialysis patients (HD) of the same age and mean arterial pressure (MAP). Blood chemistry, including blood lipids, and echographic dimensions of the aorta, were measured in all subjects. Presence of aortic calcification was evaluated by abdominal X-ray and echography. Whereas femoral and brachial PWV were only slightly increased in HD (P less than 0.05), the aortic PWV was significantly elevated (1113 +/- 319 cm/sec) in comparison with CS (965 +/- 216 cm/sec; P = 0.0016). Aortic diameters were larger in HD, both at the root of aorta (32.7 +/- 4 vs. 28.2 +/- 2.8 mm; P less than 0.0001) and aortic bifurcation (16.9 +/- 3.1 vs. 14.6 +/- 2.2 mm; P less than 0.0001). Although the MAP was similar in HD (109.9 +/- 19.3 mm Hg) and CS (110.2 +/- 17.2 mm Hg), the pulse pressure was significantly increased in HD patients (76.6 +/- 23.7 vs. 63.9 +/- 22 mm Hg; P = 0.007). In the two populations, aortic PWV was found to increase with age (P less than 0.0001) and MAP (P less than 0.0001). The presence of aortic calcification showed only a borderline relationship with the increase in aortic PWV (P = 0.050 in CS and P = 0.069 in HD). As change in PWV is directly related to change in distensibility, and the aortic diameters were increased in HD, these results indicate that aortic wall compliance is decreased in HD, resulting in an increase in the pulsatile component of arterial pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Echocardiographic study of the left ventricle was performed in 57 selected, normotensive hemodialysis patients in comparison to 40 healthy controls matched for sex, age and blood pressure. The statistically significant abnormalities in uremic patients were an enlargement of the left ventricular end-diastolic diameter (LVEDiD) (5.58 +/- 0.60 vs. 5.05 +/- 0.5 cm; P less than 0.001) and an increase in the left ventricular radius to posterior wall-thickness ratio (r/Th) (3.65 +/- 0.68 vs. 3.27 +/- 0.44; P less than 0.001). Enlargement of the ventricle was related to anemia (P less than 0.001) and the hemodynamic effect of arteriovenous fistula. Ventricular radius to wall thickness ratio was inversely related to systolic arterial pressure in controls (P less than 0.001) and patients (P less than 0.01) with a significant upward shift of the regression in dialysis patients (P less than 0.001). In dialysis patients, the left ventricular posterior wall thickness (LVPWT) was inversely correlated to serum parathormone (PTH) level (P less than 0.001), and r/Th ratio was positively correlated to serum PTH (P less than 0.001). Bone biopsy was performed in 28 patients. Histomorphometric indexes of osteitis fibrosa were in dialysis patients, correlated to echocardiographic abnormalities; osteoclasts number was inversely correlated to LVPWT (P less than 0.001) and positively related to r/Th ratio (P less than 0.001). Osteoclastic resorption surfaces and LVPWT were inversely correlated (P less than 0.001), while a positive correlation between r/Th ratio and osteoclastic resorption surfaces was observed (P less than 0.001). Osteoblastic surfaces and tetracycline double-labeled surfaces were also correlated to LVPWT (P less than 0.001) and r/Th ratio (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Three cases of nephrectomy after transplantation with uretero-ureteral anastomosis are presented: this anastomosis in transplantation looks to be anodyne when the transplant keeps normal function. Complications become when appears a degradation of the renal function.

Some nephrotic syndroms have a very poor prognosis (life threatening) because of the protidic loss, even if the renal fonction is still normal. Only a binephrectomy can prevent this true protidic diabetes. In order, to avoid the inconvenients of surgery which can be a major problem with patients having cicatrization difficulties, a bilateral embolization of the renal arteries was done. This procedure was successfully used in two patients with nephroctic syndrom secondary to a renal amyloïdosis, who where in a cachectic state.

Echocardiographic assessment of left ventricular function was performed in 66, stable hemodialysis patients and 50 normal controls matched for sex, age and arterial blood pressure. On the basis of bone histology, hemodialysis patients were classified into two groups: (1) patients with normal bone resorption; and (2) patients with active secondary hyperparathyroidism characterized by an increased bone resorption. Left ventricular function of these two subgroups were compared together as well as with the echocardiographic characteristics of normal controls. In comparison with normal controls, hemodialysis patients with normal bone resorption had an increased left ventricular volume (P less than 0.001) and left ventricular mass (P less than 0.001) with a similar left ventricular mass-to-volume ratio. Their systolic arterial pressure--mass-to-volume ratio correlation was similar to that of normal controls, indicating an adequate myocardial hypertrophy. Patients with increased bone resorption had high parathormone and alkaline phosphatase levels; though the left ventricular dilation was similar to that of hemodialysis patients with normal bone resorption, the left ventricular mass was lower (P less than 0.001) and was similar to the left ventricular mass of normal controls. In addition, patients with increased bone resorption had a lower mass-to-volume ratio (P less than 0.001) and their systolic arterial pressure--mass-to-volume ratio correlation exhibited a significant downward shift (P less than 0.001), suggesting an inadequate myocardial hypertrophy. Patients with increased bone resorption and secondary hyperparathyroidism had an increased heart rate, a higher systolic arterial pressure and end-systolic stress. Furthermore, they had an increased velocity of fiber shortening (P less than 0.01) and shorter left ventricular ejection time (P less than 0.001). In summary, present data suggest the possibility that parathormone may exert myocardial effects in hemodialysis patients.

To investigate the mechanisms of the beneficial effect of blood transfusions (BT) on subsequent kidney transplant survival, we studied the influence of 3 planned BT on lymphocyte reactivity and on lymphocytotoxic antibody (LT) production in previously non-transfused uremic patients. A sustained and non-specific decrease in mixed lymphocyte reactivity (MLR) was observed in approximately 60% of the cases, whereas other patients had only a transient decrease but otherwise normal or even increased responses. Neither the pre-BT degree of immune responsiveness nor the clinical status of the patients had any influence on this phenomenon. Similarly, hepatitis B seroprophylaxy or vaccination did not interfere with this BT effect. Anti-HLA, LT, which are potentially harmful for the transplant, were noted in 13% of cases, while 13% additional cases displayed "cold" anti-B lymphocyte LT which do not have the same prognostic value. In some instances, suppression of cellular reactivity developed concurrently with LT production, which indicates that there is no interaction between cellular and humoral responses induced by BT.

In order to investigate the possible role of aluminum accumulation on the myocardium, 50 stable asymptomatic hemodialysis patients were studied. Patient cardiac status was assessed by echocardiography. A deferroxamine (DFO) test, together with a bone biopsy, was performed to determine the magnitude of AI accumulation. Thus, an increase in serum AI after DFO (delta AI DFO) and stainable cortical bone aluminum (SCBA) were taken as parameters of AI load. Fourteen of 50 patients had no SCBA. They differed from the 36 patients with SCBA in that they had lower left ventricular mass (LVM) (P less than 0.001), increased velocity of circumferential fiber shortening (Vcf) (P less than 0.001), and higher mitral E-F slope (P less than 0.01). In the overall population there was a mild increment in serum AI and in delta AI DFO. The duration of dialysis treatment was correlated with SCBA and delta AI DFO (P less than 0.001). A correlation was observed between LVM and delta AI DFO (P less than 0.001) and between LVM and SCBA (P less than 0.001). Multivariate correlations analysis indicated that these relationships were independent of the duration of dialysis treatment. The present data suggest that, in hemodialysis patients aluminum accumulation may be associated with increased LVM.

We have investigated whether suppression of the allogeneic response after blood transfusion (BT) could be due to inhibition of the production or activity of Interleukin-2 (IL-2), a soluble mediator involved in T lymphocyte proliferation. Reduction of IL-2 production after BT was less frequent than, but significantly associated with, non specific MLR suppression. However, MLR suppressor cells did not inhibit the release of IL-2 from autologous pre-BT lymphocytes. In addition, post-BT soluble suppressor factors of the MLR did not affect the ability of IL-2 to promote cell proliferation. Thus, although MLR suppression after BT is associated with reduced IL-2 production, this is not a major mechanism involved in this effect.