Inappropriate implantable cardioverter defibrillator shocks due to atrial far-field on the tip-to-ring channel for lead dislodgement

We reported a case of inappropriate implantable cardioverter defibrillator shocks, due to atrial far-field on the tip-to-ring channel of the fast electrical activity during atrial fibrillation, caused by lead dislocation in the right ventricle outflow tract. During these episodes the can-to-right ventricle coil signal correctly recorded the ventricular activity. The shock storm stopped when an antitachycardia pacing restored sinus rhythm.

Pregnancy-associated glycoproteins (PAGs) concentrations in water buffaloes (Bubalus bubalis) during gestation and the postpartum period

For the first time in literature this study describes the pregnancy-associated glycoprotein (PAG) profile of buffalo cows during gestation and the post-partum period using antiserum raised against PAG-molecules purified from buffalo placenta (AS#860). Ninety-eight buffalo cows, belonging to a buffalo herd subjected to a synchronization and artificial insemination (AI) program, were enrolled in this study. Blood samples were taken on days 0 (AI), 23, 25, 28, 30 and then biweekly until the end of pregnancy. Pregnancy was confirmed by ultrasonography on days 28 and 45, and by rectal palpation from day 60 onwards. Blood samples were suspended for the non-pregnant cows on day 45, while the blood of 20 buffaloes that had calved was tested every five days from the day of calving until day 50 post-calving. A cut-off value of 1.0 ng/mL was used in order to discriminate between pregnant and non-pregnant buffaloes. We used Linear Mixed models after Log(x+1) transformation to analyse the PAG concentrations. Fifty-two buffalo cows had become pregnant out of 98 synchronized (53%) and 46 remained non-pregnant (47%) as shown by ultrasonography and the PAG analysis. Significant differences (P < 0.001) in PAG concentrations were observed between the pregnant and non-pregnant buffaloes from day 23 as the PAG of the non-pregnant cows was always close to zero. Conversely, the PAG of the pregnant cows increased progressively from day AI until day 105 post-insemination and then stabilized until the end of pregnancy. Regarding pregnancy diagnosis, the sensitivity of PAG-RIA 860 system (ability of the test to correctly identify pregnant buffalo) ranged from 23% on day 23-98% on day 28 post AI; the specificity (ability to correctly identify non-pregnant buffaloes) was 100% throughout the sampling period. PAG progressively decreased from parturition to day 25 post-partum; from day 30 post-partum, the concentrations fell below 1 ng/mL and were close to 0 on the last day of observation (50 d post-partum). In conclusion, our results showed that RIA-860 is highly accurate for diagnosing pregnancy in buffaloes starting from day 28 of gestation. Furthermore, the rapid disappearance of PAG concentration after calving means that a cut-off limit in post-partum for detecting a new pregnancy is not required.

Using real-time PCR to identify pregnancy-associated glycoprotein 2 (PAG-2) in water buffalo (Bubalus bubalis) blood in early pregnancy

This study investigates for the first time mRNA pregnancy-associated glycoprotein 2 (PAG-2) expression in blood cells during early pregnancy in water buffalo. The PAGs constitute a large family of glycoproteins expressed in the outer epithelial layer of the placenta in eutherian species. All PAGs are not concomitantly expressed throughout pregnancy; some of them are expressed in the earlier phases, whereas others appear later and are expressed over a shorter period. Twenty-one lactating buffaloes were analyzed-17 females were synchronized with PRID and artificially inseminated (AI), whereas four females were synchronized but not inseminated (control group). Blood was collected at Days 0, 18, 28, 40, and 75 from AI (AI = Day 0). Expression of PAG-2 mRNA in blood samples was measured with real-time polymerase chain reaction. Pregnancy diagnosis was performed on Day 28 (D28) and Day 40 (D40) after AI by ultrasonography (US) and by PAG-1 RIA method. The females diagnosed pregnant at D28 and confirmed pregnant at D40 were defined as D28(+)D40(+) group; the females diagnosed pregnant at D28 but not confirmed pregnant at D40 were defined as D28(+)D40(-) group; and the females that were diagnosed as nonpregnant on either days were defined as D28(-)D40(-) group. PAG-2 mRNA at Day 0 was not observed in any groups. The D28(+)D40(+) group showed the highest expression, starting on Day 18 and increasing progressively up to Day 75. PAG-2 mRNA was also expressed on Day 18 in both D28(+)D40(-) and D28(-)D40(-) groups, but their levels were lower than those of D28(+)D40(+) group and almost constant over time. PAG-2 mRNA was never detected in the control group. The significant difference in the expression of PAG-2 mRNA between the D28(+)D40(+) group and the D28(-)D40(-) group, starting from Day 18, suggests that these animals might have conceived, but have experienced early embryonic loss; therefore, the PAG-2 mRNA was still present in blood circulation although at lower levels, as found in the D28(+)D40(-) group. In conclusion, this study shows that PAG-2 mRNA can be detected in peripheral maternal blood cells earlier than circulating PAG-1 molecules and could be useful for studies on early pregnancy and embryonic mortality.

An impedance method for spatial sensing of 3D cell constructs--towards applications in tissue engineering

We present the characterisation and validation of multiplexed 4-terminal (4T) impedance measurements as a method for sensing the spatial location of cell aggregates within large three-dimensional (3D) gelatin scaffolds. The measurements were performed using an array of four rectangular chambers, each having eight platinum needle electrodes for parallel analysis. The electrode positions for current injection and voltage measurements were optimised by means of finite element simulations to maximise the sensitivity field distribution and spatial resolution. Eight different 4T combinations were experimentally tested in terms of the spatial sensitivity. The simulated sensitivity fields were validated using objects (phantoms) with different conductivity and size placed in different positions inside the chamber. This provided the detection limit (volume sensitivity) of 16.5%, i.e. the smallest detectable volume with respect to the size of the measurement chamber. Furthermore, the possibility for quick single frequency analysis was demonstrated by finding a common frequency of 250 kHz for all the presented electrode combinations. As final proof of concept, a high density of human hepatoblastoma (HepG2) cells were encapsulated in gelatin to form artificial 3D cell constructs and detected when placed in different positions inside large gelatin scaffolds. Taken together, these results open new perspectives for impedance-based sensing technologies for non-invasive monitoring in tissue engineering applications providing spatial information of constructs within biologically relevant 3D environments.

Defects Induced by Protons and γ-Rays in Semi-Insulating Gaas Detectors

Semi-insulating gallium arsenide has been irradiated by protons and by gamma-rays with different doses. The irradiation-induced deep level defects have been investigated by current transient spectroscopy to find their energy, capture cross sections and generation rate.Two electron traps at Ec+0.14eV(E13) and Ec-0.70eV(E4) and a hole trap at Ec-0.14eV(H2) in addition to the levels existing before the irradiation have been detected in the irradiated samples. These findings have been related to the performance of gallium arsenide charge particle detectors.

First optical hyperfine structure measurement in an atomic anion

We have investigated the hyperfine structure of the transition between the 5d{7}6s{2} {4}F{9/2}{e} ground state and the 5d{6}6s{2}6p {6}D{J}{o} excited state in the negative osmium ion by high-resolution collinear laser spectroscopy. This transition is unique because it is the only known electric-dipole transition in atomic anions and might be amenable to laser cooling. From the observed hyperfine structure in 187Os- and 189Os- the yet unknown total angular momentum of the bound excited state was found to be J=9/2. The hyperfine structure constants of the {4}F{9/2}{e} ground state and the {6}D{9/2}{o} excited state were determined experimentally and compared to multiconfiguration Dirac-Fock calculations. Using the knowledge of the ground and excited state angular momenta, the full energy level diagram of 192Os- in an external magnetic field was calculated, revealing possible laser cooling transitions.

Validation of a new pregnancy-associated glycoprotein radioimmunoassay method for the detection of early pregnancy in ewes

The aim of the current study was to describe the use of a pool of different antisera raised against pregnancy-associated glycoproteins (PAGs; purified from both ovine and caprine placentas) for early pregnancy diagnosis in ovine species. Sixty-three pluriparous Sarda ewes (Ovis aries) were synchronized. Blood samples were withdrawn on Days 18, 24, 26, 28, 30, and 50 after mating. These samples were assayed for progesterone (radioimmunoassay [RIA] including an extraction step) and for pregnancy-associated glycoproteins (RIA-706 and RIA-srPool). Progesterone concentrations were under 1.0 ng/mL in all nonpregnant Sarda ewes. In pregnant ewes, mean progesterone concentrations ranged from 2.4 ng/mL (Day 24, single pregnancies) to 4.4 ng/mL (Day 28, multiple pregnancies). During all periods of examination, PAGs remained lower than 0.8 ng/mL in nonpregnant ewes. On Day 18 of pregnancy, PAG concentrations could be detected in 26 of 43 (60.5%) and in 41 of 43 (95.3%) pregnant ewes using the RIA-706 and RIA-srPool methods, respectively. From Day 24 to Day 50, using both RIA methods, PAGs could be detected in all pregnant ewes. On Day 24, the best threshold for pregnancy diagnosis was obtained by use of RIA-srPool, maximal concentration in nonpregnant ewes being 0.3 ng/mL and minimal concentration in pregnant ewes being 4.8 ng/mL. In general, progesterone and PAG concentrations were higher in multiple pregnancies than in single pregnancies. However, because of large individual variations, single pregnancies could not be differentiated from multiple pregnancies.

High-resolution laser spectroscopy on the negative osmium ion

We have applied a combination of laser excitation and electric-field detachment to negative atomic ions for the first time, resulting in an enhancement of the excited-state detection efficiency for spectroscopy by at least 2 orders of magnitude. Applying the new method, a measurement of the bound-bound electric-dipole transition frequency in (192)Os- was performed using collinear spectroscopy with a narrow-bandwidth cw laser. The transition frequency was found to be 257.831 190(35) THz [wavelength 1162.747 06(16) nm, wave number 8600.3227(12) cm(-1)], in agreement with the only prior measurement, but with more than 100-fold higher precision.

Temporally controlled modulation of antihydrogen production and the temperature scaling of antiproton-positron recombination

We demonstrate temporally controlled modulation of cold antihydrogen production by periodic RF heating of a positron plasma during antiproton-positron mixing in a Penning trap. Our observations have established a pulsed source of atomic antimatter, with a rise time of about 1 s, and a pulse length ranging from 3 to 100 s. Time-sensitive antihydrogen detection and positron plasma diagnostics, both capabilities of the ATHENA apparatus, allowed detailed studies of the pulsing behavior, which in turn gave information on the dependence of the antihydrogen production process on the positron temperature T. Our data are consistent with power law scaling T (-1.1+/-0.5) for the production rate in the high temperature regime from approximately 100 meV up to 1.5 eV. This is not in accord with the behavior accepted for conventional three-body recombination.

Search for laser-induced formation of antihydrogen atoms

Antihydrogen can be synthesized by mixing antiprotons and positrons in a Penning trap environment. Here an experiment to stimulate the formation of antihydrogen in the n = 11 quantum state by the introduction of light from a CO2 continuous wave laser is described. An overall upper limit of 0.8% with 90% C.L. on the laser-induced enhancement of the recombination has been found. This result strongly suggests that radiative recombination contributes negligibly to the antihydrogen formed in the experimental conditions used by the ATHENA Collaboration.

The BNP assay does not identify mild left ventricular diastolic dysfunction in asymptomatic diabetic patients

AIMS

We examined the usefulness of BNP for screening for left ventricular (LV) diastolic dysfunction in a sample of type 2 diabetic patients, without structural heart disorder, who have never presented symptoms or signs of heart failure (HF).

METHODS AND RESULTS

Seventy-six consecutive patients admitted to the Outpatient Diabetes Clinic were studied. Blood samples were analyzed using the Triage BNP fluorescence immunoassay (Biosite Diagnostics, La Jolla, CA, USA). Echocardiography examinations were performed, with no knowledge of the BNP value. A total of 39 patients out of 76 (51%) were diagnosed with LV diastolic dysfunction and 23 (30%) with LV hypertrophy. Of the patients with LV diastolic dysfunction, impaired relaxation and pseudonormal pattern accounted for 97 and 3% of the cases, respectively. BNP levels among subjects with LV diastolic dysfunction (26+/-22 pg/ml, n=39) were not significantly different from patients with normal LV function (24+/-23 pg/ml, n=37 pg/ml; Mann-Whitney U-test, Z=-0.4, n.s.).

CONCLUSIONS

Our data confirm alarmingly high prevalence of LV diastolic dysfunction in asymptomatic individuals with diabetes. Identification of patients with preclinical diabetic cardiomyopathy should be a research and clinical priority. BNP levels cannot be used to detect mild LV diastolic dysfunction in this subset of patients, which requires Doppler echocardiography to be detected.

B-Type Natriuretic Peptide Can Predict the Medium-Term Risk in Patients With Acute Heart Failure and Preserved Systolic Function

BACKGROUND

Half of patients with heart failure (HF) have preserved left ventricular ejection fraction (LVEF). Neurohormonal activation characterizes the disease and measurement of plasma B-type natriuretic peptide (BNP) indicates the severity of left ventricular dysfunction. The purpose of this study was to test the hypothesis that measurement of BNP levels in ambulatory patients with HF and preserved LVEF can predict the occurrence of cardiovascular events in the next 6 months.

METHODS AND RESULTS

We enrolled 233 consecutive patients admitted to the Outpatient Heart Failure Clinic (OHFC), on stabilization after an episode of acute HF, with a LVEF > 50%. Standard echocardiography was performed and left ventricular systolic/diastolic function was assessed. Plasma BNP levels were measured on admission to OHFC. Patients were followed for 6 months; the main endpoint combined cardiovascular death or readmission for HF. Among the 233 patients discharged, 48 endpoints occurred (death: n = 15; readmission: n = 33). Receiver operated curve analysis shows that BNP levels are strong predictors of subsequent events (area under the curve = 0.84; CI = 0.78-0.88). Multivariate Cox regression showed that the cutoff values identified by receiver operated curve analysis (200-500 pg/mL) of the neurohormone are the most accurate predictors of events: HR = 2.2 (P < .04) and HR = 5.8 (P < .001), respectively, for 201-499 pg/mL and > or = 500 pg/mL ranges.

CONCLUSION

BNP level is a strong predictor for cardiovascular mortality and early readmission in patients with diastolic HF. The results suggest that BNP levels might be used successfully to guide the intensity of follow-up after a decompensation, because increased BNP levels were associated with a progressively bad prognosis.

Prognostic value of plasma brain natriuretic peptide, urea nitrogen, and creatinine in outpatients >70 years of age with heart failure

This study analyzed the relevance of plasma brain natriuretic peptide (BNP) and echocardiography in predicting cardiovascular events in a large population >70 years old with heart failure (HF). Three hundred four outpatients with HF (51.6% men, mean age 78.6) underwent transthoracic echocardiography and plasma BNP testing shortly before hospital discharge. Echocardiography was intended to reveal systolic dysfunction (left ventricular [LV] ejection fraction [EF] <50%) or diastolic dysfunction (EF > or =50% and abnormalities of ventricular relaxation). During 6-month follow-up, all-cause death and readmission were assessed. One hundred seventeen patients had diastolic dysfunction with preserved systolic LV function, and 187 had systolic dysfunction. At 6-month clinical follow-up, 33 subjects (10.9%) had died, and 62 (20.4%) needed readmission for cardiac decompensation. In all patients, univariate logistic regression demonstrated significant correlations between age (r = 0.14, p = 0.01), plasma BNP (r = 0.36, p = 0.0001), the EF (r = 0.16, p = 0.003), urea nitrogen (r = 0.35, p = 0.0001), serum creatinine (r = 0.27, p = 0.0001), and New York Heart Association (NYHA) class (r = 0.35, p = 0.0001) and the occurrence of cardiovascular events. In patients with HF in NYHA class III or IV, a BNP cut-off level of 200 pg/ml identified different outcomes (BNP <200 pg/ml in 1 of 20 events vs BNP >200 pg/ml in 55 of 85 events, p = 0.0001). In patients with HF who were >70 years old, BNP, NYHA class, and renal function predicted adverse outcome. In patients with severe HF, BNP was better than NYHA class in predicting future events.

New source of dense, cryogenic positron plasmas

We have developed a new method, based on the ballistic transfer of preaccumulated plasmas, to obtain large and dense positron plasmas in a cryogenic environment. The method involves transferring plasmas emanating from a region with a low magnetic field (0.14 T) and relatively high pressure (10(-9) mbar) into a 15 K Penning-Malmberg trap immersed in a 3 T magnetic field with a base pressure better than 10(-13) mbar. The achieved positron accumulation rate in the high field cryogenic trap is more than one and a half orders of magnitude higher than the previous most efficient UHV compatible scheme. Subsequent stacking resulted in a plasma containing more than 1.2 x 10(9) positrons, which is a factor 4 higher than previously reported. Using a rotating wall electric field, plasmas containing about 20 x 10(6) positrons were compressed to a density of 2.6 x 10(10) cm(-3). This is a factor of 6 improvement over earlier measurements.

The NT-proBNP assay identifies very elderly nursing home residents suffering from pre-clinical heart failure

BACKGROUND

Little is known about the prevalence of heart failure among very old people, although hospitalisation rates for chronic heart failure are very high. Recently, brain natriuretic peptides have emerged as important diagnostic and prognostic serum markers for congestive heart failure.

AIMS

The main purpose of our study was to determine whether there is a cut-off for NT-proBNP for detecting the echocardiographic features of left ventricular systolic and/or diastolic dysfunction and clinical heart failure among old people living in nursing homes. Secondarily, we investigated the medium-term prognostic power of the neurohormone levels.

METHODS

We screened 101 old people (80% females, aged 84+/-9 years) from two nursing homes. We prospectively evaluated whether we could effectively stratify patients using a combination of (1) restrictive clinical criteria, (2) NT-proBNP measurements (Elecsys System, Roche Diagnostics) and (3) echocardiography for all patients.

RESULTS

Forty-two percent of the subjects had left ventricular dysfunction: 11% systolic, 23% diastolic and 8% both systolic and diastolic. The mean NT-proBNP concentration was 2806+/-7028 pg/ml in the 42 patients with left ventricular systolic and/or diastolic dysfunction, compared with 365+/-456 pg/ml in the 59 patients with normal left ventricular function (p<0.01, Z=-4.8 Mann-Whitney U test). The neurohormone proved to be a good predictor of events within 6 months [area under the receiver-operated curve (ROC)=0.79].

CONCLUSIONS

Blood NT-proBNP concentrations can play an important role in stratifying old people into left ventricular dysfunction risk groups. The neurohormone is an independent marker for death or admission for heart failure in the medium term.

[Is early discharge possible in patients with uncomplicated heart failure? Cost-efficacy analysis]

BACKGROUND

Heart failure is a common indication for admission to the hospital among old adults. The hospital stay for uncomplicated heart failure is often too long. We hypothesized that a rapid optimization of care and a guideline-based approach would allow an early discharge of patients, still maintaining a greater quality and efficiency of care.

METHODS

We conducted a randomized trial of the effect of a guideline-based intervention on rates of readmission within 90 days of hospital discharge and costs of care for patients who were hospitalized for heart failure and discharged after 4 days of stay. The intervention consisted of early echocardiography, aggressive diuretic therapy, comprehensive education of the patient and family, a prescribed diet, and intensive application of the guidelines' recommendations on pharmacological therapy. Fifty early-discharged patients were compared to 50 concurrent normally-discharged patients.

RESULTS

Average length of stays during baseline admissions was shorter for early-discharged patients respect to controls (3.9 +/- 0.8 vs 7.0 +/- 1.9 days, p < 0.001). At discharge, when compared with control patients, early-discharged patients were similarly prescribed and/or were taking similar dosages of ACE-inhibitors (84 vs 80% and 17 vs 15 mg/die, p = NS), beta-blockers (64 vs 56% and 14 vs 16 mg/die, p = NS), spironolactone (86 vs 70% and 36 vs 32 mg/die, p = NS), digoxin (74 vs 70% and 0.18 vs 0.15 mg/die, p = NS), and losartan (8 vs 6% and 50 mg/die for both groups, p = NS). Hospital readmission rates and days of stay were similar between groups (6 vs 8% and 18 vs 26 days, respectively for study and control patients), whilst the overall costs of care were lower for early-discharged patients (289 vs 449 [symbol: see text] per patient per month), due to the shorter length of stay at baseline. Survival for 90 days was achieved in 47 patients both in the study and control groups (p = NS).

CONCLUSIONS

Our study showed that patients admitted for heart failure may be safely discharged 4 days after admission. An in-hospital guideline-based management of patients allows relevant cost savings, reducing hospital readmission for heart failure.

The medicalization of menopause: implications for recruitment of study participants

OBJECTIVE

Early studies of menopause recruited sample populations from clinical settings; however, in the 1970s, populations drawn from health care settings were characterized as nonrepresentative because of symptom overreporting. This pilot study was carried out to test whether this characterization still holds true: that women who are drawn from clinical settings report more symptoms compared with women who are recruited from community and work sites.

DESIGN

Open-ended interviews were carried out with patients aged 40-60 years in a physician's office (n = 50), in a chiropractor's office (n = 24), at two Breast Health Project sites (n = 50), and in several non-health care sites in the community (n = 81). Interviews were supplemented by anthropometrics and standardized return-by-mail questionnaires.

RESULTS

Women who experienced hot flashes and sweating were more likely to report having spoken with a physician about menopause. However, women who were drawn from the clinical setting were not significantly more likely to describe hot flashes, sweats, or mood changes and were significantly less likely to report headaches in relation to menopause compared with a community sample. Women who were drawn from the physician's office were more likely to use hormone replacement therapy and to have had a hysterectomy.

CONCLUSIONS

This study suggests that because of the medicalization of menopause, we need to rethink our assumptions about the characteristics of populations drawn from health care settings. In western Massachusetts, place of recruitment did not predict symptom frequency.

Effects of induced endometritis on the life-span of corpora lutea in pseudopregnant rabbits and incidence of spontaneous uterine infections related to fertility of breeding does

A significant percentage of rabbit does fail to become pregnant after AI. We hypothesized that uterine infections induced by the insemination procedure are related to delayed luteolysis and high progesterone concentrations noted to present at the time of AI. The rabbits, randomly assigned to 4 groups (3 animals/group), were given 0.8 microgram GnRH analogue (Day 0) just prior to infusing the uterus with sterile extender (control group) or with extender inoculated with 0.5, 1, and 2 x 10(6) Pasteurella multocida (treated groups). The effects of treatments on functional life-span of CL were assessed by evaluating plasma progesterone from Day 0 to Day 23 of pseudopregnancy. In treated rabbits, the progesterone profiles closely overlapped those found in controls until approximately Day 14. Thereafter, they varied greatly between animals, but luteolysis was delayed by at least 5-6 d and developed less rapidly than in controls. On Day 21, progesterone concentrations were higher than normal in 4 treated does. In a field survey, vaginal swabs were collected at the time of the second AI from 114 non-pregnant rabbits and those positive to bacteriological culture, were killed humanely 16 d later to collect uterine swabs. Positive uterine swabs were found only in 19 of the 34 does having a positive vaginal swabs and all of them were not pregnant. The most frequent pathogen isolated was S. aureus (50%), followed by E. coli (37.5%) and P. multocida (12.5%). We demonstrated that uterine infection increases the life-span of CL in non-pregnant does and that infections of the genital tract system are quite common among does on breeding farms, probably related to using AI.

Nitric oxide synthase acutely regulates progesterone production by in vitro cultured rabbit corpora lutea

We examined the presence and the regulation of nitric oxide (NO) synthase (NOS) using in vitro cultured corpora lutea (CL) obtained from rabbits at days 4 and 9 of pseudopregnancy. The role of NO and NOS on steroidogenesis was also investigated using the same CL preparations after short-term incubations (30 min and 2 h) with the NO donor, sodium nitroprusside (NP), the NOS inhibitor, Nomega-nitro-l-arginine methyl ester (l-NAME) and prostaglandin (PG) F-2alpha. The basal NOS activity was greater in CL at day 4 than at day 9, and was also differently modulated by PGF-2alpha, depending on the age of the CL. The addition of PGF-2alpha to day 4 CL had no effect, but PGF-2alpha on day 9 caused a threefold increase in NOS activity. NP caused a two- to fivefold decrease in release of progesterone from CL of both ages, and this inhibitory effect on steroidogenesis was reversed by l-NAME. All treatments failed to modify basal androgens and 17beta-oestradiol was not detectable in either control or treated CL. These results suggest that NO is effectively involved in the regulation process of steroidogenesis, independently of 17beta-oestradiol. PGF-2alpha had no effect on day 4, but induced luteolysis on day 9, by reducing progesterone (P</=0. 01) to about 18% of control. The luteolytic action of PGF-2alpha was completely reversed by co-incubation with l-NAME, thus supporting the hypothesis that luteolysis is mediated by NO. The addition of NP or l-NAME did not modify the in vitro release of PGF-2alpha. We hypothesised that PGF-2alpha upregulates NOS activity and, consequently, the production of NO, which acutely inhibits progesterone release from day 9 CL of pseudopregnant rabbits.

Changes in refractoriness of rabbit corpora lutea to a prostaglandin F2 alpha analogue, alfaprostol, during pseudopregnancy

The responsiveness of rabbit corpus luteum to 200 micrograms of the prostaglandin F2 alpha (PGF2 alpha) analogue, alfaprostol, between Days 3 and 9 of pseudopregnancy was assessed by evaluating the decline in plasma progesterone after treatment with PGF2 alpha in 81 New Zealand White (NZW) rabbits. On Days 3-5, functional luteolysis was not observed. On Days 6, 7, and 8 of pseudopregnancy, the number of rabbits responsive to PGF2 alpha, rose from 38% to 71% and 83%, respectively. In the other cases, the effect of the PGF2 alpha analogue was transient as CL recovered in the following 2 or 3 days. By contrast, on Day 9 luteolysis was effective and persistent in all the animals. In rabbits treated on Day 9, progesterone decreased gradually from 10.6 +/- 0.7 within the first 6 h, but fell to 3.6 +/- 1.5 ng/mL (p < 0.01) 12 h after PGF2 alpha and to 0.2 +/- 0.1 ng/mL (p < 0.01) 24 h later.

Study on the elimination of Angiostrongylus costaricensis first stage larvae in the experimental infection of Swiss mice

Abdominal angiostrongylosis is a nematode infection wild rodents. Human infection may result in severe abdominal disease and has been reported from several countries in the Americas. The domestic mouse, Mus musculus, has not been found with natural infection and, like other urban rodents, should not be considered a natural host for Angiostrongylus costaricensis. Quantification of parasitic forms released for transmission may better express the coevolutionary status in parasite-host relationship. With this objective, five groups of experimentally infected Swiss mice were followed for up to 155 days post-infection (PI) days and the quantification of first stage larvae (L1) output revealed: an irregular elimination of L1 and a huge variation in the patency period (1 to 114 days) and in the number of L1 eliminated daily by individual animals (1 to 6340 L1/g). Overall mortality was 72% (range: 28% to 100%) at seven weeks PI. In conclusion, abdominal angiostrongylosis in M. musculus presents high mortality and a very variable and irregular elimination of L1 in feces.

Structural abnormalities and not diastolic dysfunction are the earliest left ventricular changes in hypertension. HARVEST Study Group

It has been claimed that diastolic dysfunction is the earliest cardiac abnormality in hypertension, preceding the development of left ventricular (LV) structural abnormalities. To detect early signs of hypertensive cardiac involvement 722 subjects (533 men and 189 women), 18-45 years old, with stage I hypertension, were studied by M-mode and Doppler echocardiography. Blood pressure was measured by 24-h ambulatory monitoring. Ninety-five normotensive individuals of similar age and gender distributions were studied as controls. Significant, though modest, changes of LV mass and geometry were found in the participants in comparison with the normotensive controls. The increment was +10.4 g/m2 for LV mass index, +1.8 mm for LV wall thickness, and +0.032 for relative wall thickness. A slight increase in atrial filling peak velocity was found in the hypertensive subjects at Doppler analysis of transmitral flow, but the ratio of early to atrial velocity of LV diastolic filling did not differ between the two groups. In multiple regression analyses, which included age, body mass index, heart rate, smoking, and physical activity, 24-h mean blood pressure emerged as a significant predictor of LV mass index (men, P = .003; women, P = .04) and wall thickness (men, P = .03; women, P = .004) in the hypertensive subjects, whereas no index of diastolic filling was significantly associated with ambulatory blood pressure in either gender. The present data indicate that changes in LV anatomy are the earliest signs of hypertensive cardiac involvement. Left ventricular filling is affected only marginally in the initial phase of hypertension.

Interactive action of the white-coat effect and the blood pressure levels on cardiovascular complications in hypertension

PURPOSE

This study was undertaken to investigate whether there is a relationship between the white-coat effect and the cardiovascular complications of hypertension.

PATIENTS AND METHODS

In 1,013 consecutive borderline to severe hypertensive outpatients (889 men) with a mean age (+/-SE) of 33.6 +/- 0.5 years and a mean office blood pressure of 152.3 +/- 0.6/95.5 +/- 0.4 mm Hg, blood pressure was measured by noninvasive 24-hour ambulatory monitoring. Target organ damage was assessed by electrocardiogram, chest X-ray, echocardiography, and ophthalmoscopy. The degree of target organ damage and of left ventricular hypertrophy was assessed in the subjects divided according to the levels of their daytime blood pressure and the extent of their white-coat effect.

RESULTS

The subjects with a high white-coat effect showed a greater degree of hypertensive complications than those with intermediate or a low white-coat effect. The significant association between the white-coat phenomenon and the hypertensive complications was confirmed by the results of stepwise regression analyses, where sex, age, duration of hypertension, and ambulatory blood pressure were added to the model. A two-way ANOVA showed that both ambulatory blood pressure and the white-coat effect were related to the degree of target organ damage and to left ventricular hypertrophy. Moreover, daytime blood pressure and the white-coat effect showed an interactive effect on hypertensive complications, as the influence of the white-coat effect on end organs increased with increasing levels of ambulatory blood pressure.

CONCLUSIONS

The present results show that the white-coat effect is related to the degree of hypertensive complications and that this association is stronger in the subject with more severe hypertension.

Does orthostatic testing have any role in the evaluation of the young subject with mild hypertension?: an insight from the HARVEST study

The aim of the study was to assess the clinical significance of the blood pressure (BP) reaction to standing in 1029 stage I hypertensives. Office BP was measured six times in the supine position and six times after 2 min of standing. All subjects underwent 24-h ambulatory BP monitoring, and measurements of 24-h urinary epinephrine and norepinephrine excretion. Echocardiography was performed in 636 patients. With use of mixture analysis we could single out a population with abnormal diastolic BP response to standing (hyperreactors, n = 95). These subjects had a diastolic BP increase from lying to standing of >11 mm Hg. The other subjects were defined as normoreactors (n = 934). Office systolic BP was similar in the two groups. Diastolic BP was lower (91 +/- 6 mm Hg v 95 +/- 5 mm Hg, P < .0001) and heart rate was higher in the hyperreactors (77 +/- 10 beats/min v 75 +/- 9 beats/min, P = .004). After adjusting for age, gender, and smoking habits the statistical significance did not change. Adjusted 24-h systolic BP (P = .02) and diastolic BP (P = .02) were higher in the hyperreactors than in the normoreactors. Hyperreactors were characterized by higher cardiac index (3.2 +/- 0.8 L/min/m2 v 3.0 +/- 0.7 L/min/m2, P = .008 for adjusted values), lower total peripheral resistance (1420 +/- 330 dyne/sec/cm(-5) v 1600 +/- 380 dyne/sec/cm(-5), P = .003), and higher urinary norepinephrine output (114.9 +/- 80.3 microg/24 h v 90.6 +/- 78.5 microg/24 h, P = .03). Dimensional echocardiographic data and albumin excretion rate did not differ between the two groups. In conclusion, mixture analysis allowed us to identify a population of young mild hypertensives with exaggerated BP response to standing. Hyperreactors were characterized by higher whole-day BP and by a hyperkinetic hemodynamic pattern as a result of increased sympathetic tone.

Ambulatory blood pressure monitoring editing criteria: is standardization needed? Hypertension and Ambulatory Recording Venetia Study (HARVEST) Group, Italy

The effect of different editing methods on the reproducibility of ambulatory blood pressure and on its correlation with microalbuminuria was studied in a population of 584 stage I hypertensives participating in the Hypertension and Ambulatory Recording Venetia Study (HARVEST) Group. For systolic blood pressure (SBP), a modified version of the Casadei method showed the best reproducibility indices, followed by the original Casadei and the Kennedy methods. The Staessen, SpaceLabs, and A&D methods showed poorer indices, irrespective of whether calculations were made in recordings with more or less than 10% artifactual readings. For diastolic blood pressure (DBP), reproducibility indices did not substantially vary with the various editing procedures except for the Kennedy method, which showed a slightly better performance. Blood pressure variability (standard deviation) showed a better reproducibility with the original and modified versions of the Casadei and the Kennedy procedures than with the other methods, especially in the subjects with percentage of measurement errors greater than 10%. The correlation coefficients between 24-h SBP and albumin excretion rate ranged from 0.128 for the raw data to 0.154 for the data edited according to the Casadei procedures. For DBP, the correlation coefficients were similar except for DBP edited with the Kennedy method, which did not correlate with albumin excretion rate to a statistically significant level. These data suggest that, to make the results of different laboratories comparable, common ambulatory blood pressure editing criteria should be used. The modified version of the Casadei procedure, which is automatic and can be applied to recordings obtained from any device, should be regarded as the method of choice.

Remodeling of the left ventricle in primary aldosteronism due to Conn's adenoma

BACKGROUND

Since hyperaldosteronism has been experimentally related to myocardial interstitial fibrosis, we investigated the effects of hypertension and excess aldosterone due to aldosterone-producing adenomas (APAs) on the heart.

METHODS AND RESULTS

In 52 hypertensive individuals, we performed Doppler echocardiography for estimation of left ventricular (LV) wall thickness and dimensions, transmitral LV filling flow velocity indexes, and 24-hour ambulatory blood pressure monitoring. Consecutive patients with APAs (n = 26) and essential hypertension (EH, n = 26) were individually matched for age, sex, race, body mass index, casual blood pressure, and known duration of hypertension. The matched groups were similar for demography, casual and 24-hour blood pressure values and variability, and duration of hypertension but differed for serum potassium, plasma renin activity, and aldosterone levels (all P < .001). A thicker interventricular septum (P = .015) and posterior wall (P = .009) and a higher LV mass index (118 +/- 5 versus 100 +/- 4 g/m2, P = .009) were observed in APA compared with EH patients. Both septum and posterior wall thicknesses had a significant direct relationship with age, plasma aldosterone, and mean blood pressure. The integral of the early diastolic filling wave (Ei) (P = .011) and the ratio Ei/Ai (A wave integral) (P = .038) were lower and the atrial contribution to LV filling was higher (52 +/- 2% versus 46 +/- 2%, P = .038) in APA than in EH patients. The ratio Ei/Ai was significantly (P = .008) inversely related only to age and plasma aldosterone.

CONCLUSIONS

In APA patients, the excess aldosterone is associated with both increased LV wall thickness and mass and decreased early diastolic LV filling indexes compared with demographically similar EH with superimposable blood pressure values, profile, and variability.

Relation of 24-hour ambulatory blood pressure and short-term blood pressure variability to seasonal changes in environmental temperature in stage I hypertensive subjects. Results of the Harvest Trial

We investigated the seasonal changes in blood pressure (BP) and in short-term BP variability determined using ambulatory blood pressure monitoring (ABPM). 1000 white subjects, who took part in the multicenter HARVEST study, underwent ABPM with the A&D TM-2420 or the Spacelabs 90207. Standard deviation of the mean daytime and nighttime BP was taken as an index of short-term BP variability (v). Maximal outdoor temperature (Tmax) during each ABPM was obtained from local Meteorological Centers. Subjects were divided according to season and to quartiles of Tmax. A subgroup of 46 persons who repeated ABPM in Winter and Summer was also studied. We observed evident seasonal differences in office and ambulatory systolic BP (SBP) with a peak during Winter. Diastolic BP (DBP) and heart rate did not vary throughout the four seasons. Office SBP (p < 0.01), 24-hour (p < 0.002), daytime SBP (p < 0.0001), both daytime SBPv (p < 0.0001), DBPv (p < 0.02), and nighttime SBPv (p < 0.05), DBPv (p < 0.02) as well as norepinephrine (p < 0.005) were significantly higher during Winter than Summer. Similar differences were observed in subjects grouped in quartiles of Tmax. In the subgroup daytime but not nighttime SBP was higher in the cold season. Average 24-hour SBP (p < 0.05), daytime SBP (p < 0.02), daytime SBPv (p < 0.001) and DBPv (p < 0.05) and norepinephrine (p < 0.0001) were significantly negatively correlated with Tmax in the whole population. BP is higher and subjected to wider oscillations during the cold season in patients with mild hypertension probably due to sympathetic activation. The assessment of a hypertensive subject may give different results according to the season.

Relationship of plasma renin activity with caffeine intake and physical training in mild hypertensive men. HARVEST Study Group

To study the relationship between plasma renin activity (PRA) and coffee consumption, cigarette smoking, alcohol intake and physical activity habits.

SETTING

The multicentre HARVEST trial, involving 17 Hospital Centres in Northeast Italy.

SUBJECTS

351 borderline to mild hypertensive men (mean age +/- SEM 22.7 +/- 0.47 years), never treated for hypertension.

INTERVENTIONS

Office and 24-hour blood pressure measurement, supine and standing PRA levels, and urinary catecholamines output.

MAIN OUTCOME MEASURES

PRA levels according to coffee intake and physical activity status.

RESULTS

Coffee intake showed a major effect on PRA. Supine PRA levels were 40% higher in the subjects abstaining from coffee (n = 94) than in the coffee drinkers and was similar in the moderate (n = 223) and heavy (n = 34) drinkers. A weaker negative association was found between coffee use and PRA on standing. Office and whole-day blood pressure and heart rate, and urinary catecholamines did not differ according to coffee intake. Supine PRA was lower in the subjects performing regular physical activity than in the inactive subjects. Office and whole-day diastolic blood pressure and heart rate, and urinary norepinephrine were lower in the active than in the sedentary men. No relationship was found between PRA measured either in the supine or the upright posture and tobacco or alcohol use. In a multiple linear regression model supine PRA was negatively correlated with age, coffee consumption and physical activity habits.

CONCLUSIONS

Chronic coffee intake and physical training showed an inverse relationship with PRA in mild hypertensive men, while tobacco and alcohol use were unrelated to PRA.

Supernormal left ventricular performance in young subjects with mild hypertension: an alerting response to the echocardiographic procedure?

1. To assess the clinical significance of supernormal left ventricular systolic function in the initial phase of hypertension, 635 never-treated 18-45-year-old borderline to mild hypertensive subjects (477 males, 158 females) were studied. All subjects underwent echocardiography, 24 h ambulatory blood pressure monitoring and 24 h urine collection for catecholamine dosage. 2. Subjects whose left ventricular shortening-stress relationship was above the 95% confidence intervals of 50 normotensive subjects of similar age and sex distribution were defined as having supernormal function. 3. Age, duration of hypertension and left ventricular mass were similar in the hypertensive subjects with normal (85%) and supernormal (15%) ejective performance. Subjects with supernormal function showed higher office systolic blood pressure (P < 0001), office heart rate (P = 0.03) and cardiac index (P < 0001). Conversely, 24 h systolic blood pressure, 24 h heart rate and 24 h catecholamine output did not differ according to left ventricular function. 4. In conclusion, the greater white-coat effect and the normal baseline sympathetic tone exhibited by the patients with increased performance suggest that supernormal left ventricular pump function is only a marker of the alerting reaction elicited by the echocardiographic examination.

Changes in left ventricular anatomy and function in hypertension and primary aldosteronism

We investigated the effects on the heart of hypertension due to the excess of aldosterone and suppression of the renin-angiotensin system caused by primary aldosteronism with M-mode echocardiography and transmitral Doppler flow velocity measurements. We studied 34 consecutive patients with primary aldosteronism and 34 with essential hypertension individually matched for age, gender, race, body mass index, blood pressure values, and duration of hypertension. The groups were similar in age, body mass index, blood pressure, and duration of hypertension. However, lower serum potassium levels (3.5 +/- 0.6 versus 4.1 +/- 0.2 mmol/L, P < .0001) and plasma renin activity (0.53 +/- 0.45 versus 1.82 +/- 1.59 ng Ang I x mL-1 x h-1, P < .0001) and higher plasma aldosterone levels (1107 +/- 774 versus 206 +/- 99 pmol/L, P < .0001), left ventricular wall thickness, and left ventricular mass index (112 +/- 4.7 versus 98 +/- 3.7 g/m2, P = .029) were found in patients with primary aldosteronism compared with those with essential hypertension. Similarly, the PQ interval was longer (173 +/- 20 versus 141 +/- 14 milliseconds, P < .001) in primary aldosteronism than in essential hypertension patients. Significantly more primary aldosteronism than essential hypertension patients had left ventricular hypertrophy or left ventricular concentric remodeling (50% versus 15%, chi 2 = 11.97, P = .007). Both the E wave flow velocity integral (1063 +/- 65 versus 1323 +/- 78, P = .013) and the E/A integral ratio (0.91 +/- 0.05 versus 1.25 +/- 0.08, P < .001) were lower, and atrial contribution to left ventricular filling was higher (53.3 +/- 1.5% versus 45.5 +/- 1.3% P < .001) in patients with primary aldosteronism compared with essential hypertension patients. After 1 year of follow-up, highly significant decreases of left ventricular wall thickness and mass were observed in patients treated with surgical excision of an aldosterone-producing tumor, but not in those with medical therapy. Thus, in patients with primary aldosteronism, the excess aldosterone with suppression of the renin-angiotensin system is associated with both increased left ventricular mass and significant changes of left ventricular diastolic filling. The former changes appear to be reversible on removal of the cause of excessive aldosterone production.

24 h rhythm of blood pressure and forearm peripheral resistance in normotensive and hypertensive subjects confined to bed

OBJECTIVES

To define whether a diurnal rhythm of peripheral resistance exists in normotensive and hypertensive subjects, has any relationship with that of blood pressure and differs in dipper and non-dipper hypertensives.

DESIGN AND METHODS

Forty-three subjects (13 normotensives and 30 mild-to-moderate essential hypertensives) confined for 24 h to bed were included. Blood pressure was recorded for 22 h at 15 min intervals, plethysmographic forearm flow was simultaneously measured and forearm resistance calculated. The analysis was performed for the whole 22 h period and for three 4 h truncated periods, two of certain wakefulness and one of certain sleep.

RESULTS

A circadian rhythm of forearm resistance was shown in the normotensives, paralleling that of blood pressure. All the normotensives were dippers, with a nocturnal blood pressure dip (systolic/diastolic) of -4.5/-6.0%. In the hypertensives, the day/night blood pressure trends were not homogeneous: 21 showed higher blood pressure values during waking time, with a trend quite similar to that of the normotensives, whereas the other nine were non-dippers. Resistance was lower during sleep than during waking both in the normotensives and in the dipper hypertensives, whereas in the non-dippers it was higher during sleep.

CONCLUSIONS

A sleep/waking rhythm of peripheral resistance with the highest values during daytime and the lowest during night-time does exist in normotensive as well as in the majority of hypertensive subjects resting continuously in bed, and therefore is largely independent of physical activity. Only in a minority of hypertensive patients are higher values of peripheral resistance present during sleep.

Relationship between albumin excretion rate, ambulatory blood pressure and left ventricular hypertrophy in mild hypertension

OBJECTIVE

To study the relationship of urinary albumin excretion to ambulatory blood pressure and other cardiovascular risk factors in borderline to mild hypertension.

PATIENTS AND METHODS

We studied 779 patients with borderline to mild hypertension (mean +/- SEM age 33 +/- 0.3 years; mean +/- SEM office blood pressure 146 +/- 0.4/94 +/- 0.2 mmHg) at 17 hypertension clinics in northeast Italy. Office and 24-h blood pressures were recorded with simultaneous urine collection for albumin measurement. In 510 subjects, left ventricular mass was measured by echocardiography.

RESULTS

Subjects with overt (> or = 30 mg/24 h) and borderline (16-29 mg/24 h) microalbuminuria had similar 24-h blood pressure levels, higher than those in the subjects without microalbuminuria. In the univariate and multiple regression analyses the albumin excretion rate was closely correlated with 24-h systolic blood pressure and not related to age, body mass index, metabolic parameters, lifestyle factor and degree of left ventricular hypertrophy.

CONCLUSIONS

Borderline values of urinary albumin excretion (16-29 mg/24 h) may be clinically relevant in subjects with borderline to mild hypertension. Renal and cardiac damage do not develop in parallel in the initial phases of hypertension.

[The relationship between overweight, life style and casual and 24-hour pressures in a population of male subjects with mild hypertension. The results of the HARVEST study]

AIM OF THE STUDY

To evaluate the relationship of coffee use, smoking, physical inactivity, alcohol intake and overweight with casual and ambulatory blood pressure in a large population of borderline to mild hypertensive subjects.

METHODS

Six hundred and thirty men with a mean (+/- SE) age of 33 +/- 0.4 years (range = 18-45 years) and a mean office blood pressure of 146 +/- 0.4/94 +/- 0.2 mm Hg, participating in the multicentre HARVEST study, were divided into three categories according to: coffee consumption (0 cups, 1-3 cups, > 3 cups/day), number of cigarettes smoked per day (0, 1-10, 11-20), degree of physical activity (no activity, regular training, competitive activity), alcohol intake (no alcohol, < 50 g, > or = 50 g/day) and body mass index (tertiles). All patients underwent non invasive ambulatory blood pressure monitoring with either the A&D TM-2420 model 7 or the Spacelabs 90207 monitor. Moreover, 24-hour urine collection was made for epinephrine and norepinephrine assessment (n = 611).

RESULTS

Twenty-four-hour systolic blood pressure was higher in the coffee drinkers than the nondrinkers (+2.6 mm Hg in the moderate drinkers). Instead, 24-hour diastolic blood pressure was mainly influenced by overweight (3.2 mm Hg difference between the low and high BMI tertiles) and physical inactivity (3.2 mm Hg difference between the sedentary men and the athletes). Generally, the association of the above factors was stronger with ambulatory than with office blood pressure, whereas alcohol intake was only related to office diastolic blood pressure. However, in a multivariate regression analysis alcohol use did not show an independent effect on either office or ambulatory blood pressure. Smoking showed a different effect on office and ambulatory blood pressure. In fact, office blood pressure was higher in the nonsmokers, while 24-hour blood pressure was higher in the smokers. Smoking, coffee and physical inactivity were associated with sympathetic overactivity, as documented by increased urinary catecholamines output.

CONCLUSIONS

The results of the present study indicate that overweight and behavioural factors affect 24-hour blood pressure to a larger extent than office blood pressure does. This is likely to be due to their effect on the sympathetic nervous system activity, which would enhance the blood pressure response to daily life stressors.

[Alcohol consumption, arterial pressure and metabolic parameters in a population of borderline hypertension subjects. The results of the HARVEST Multicenter Study. Hypertension and Ambulatory Recording Venetia Study]

In 544 borderline to mild hypertensive subjects (mean age 33.5 +/- 8.6 years) participating in the HARVEST trial the relationship between alcohol consumption, blood pressure levels and several clinical parameters was examined. Subjects were divided into 3 groups according to whether they did not drink (Group 1, n = 171) or their daily alcohol intake was < 50 g (Group 2, n = 184) or > 50 g (Group 3, n = 54). In the 409 men alcohol consumption was related to age (p < 0.0001), body weight (p < 0.05) and coffee consumption (p < 0.0001). Group 3 drinkers were also more sedentary than the 2 other groups (p < 0.05). Both office (p < 0.001) and 24-hour (p < 0.001) diastolic blood pressure were greater in the drinkers than in the non drinkers, while no difference was observed in systolic blood pressure. Twenty-four-hour heart rate was higher in Group 3, but urinary catecholamines were similar in the 3 groups of men. Blood glucose (p < 0.001), total cholesterol (p = 0.001) and triglyceride (p < 0.005) were related to alcohol consumption, while HDL-cholesterol was not different in the 3 groups. Albumin excretion rate and uricemia were also unrelated to alcohol intake. In the 135 women a similar alcohol-related trend was observed for office diastolic blood pressure and for the metabolic parameters. In conclusion, the results of the present study confirm the association between alcohol consumption and blood pressure levels, which was apparent also within a population of borderline to mild hypertensive subjects and stress the role of alcohol in determining an abnormality of the metabolic parameters.

Factors affecting ambulatory blood pressure reproducibility. Results of the HARVEST Trial. Hypertension and Ambulatory Recording Venetia Study

To assess the reproducibility of ambulatory blood pressure, we recorded 24-hour blood pressure twice 3 months apart in 508 hypertensive subjects participating in the HARVEST trial using a noninvasive technique. Blood pressure was measured every 10 minutes during the daytime and 30 minutes during the nighttime. Reproducibility was better for ambulatory than for office blood pressure. It was greater for 24-hour than for daytime blood pressure and lowest for nighttime blood pressure. The reproducibility of blood pressure variability (standard deviation) was poorer than that of the average values. A small but significant decrease in average daytime blood pressure (-0.8/-1.0 mm Hg) and virtually no change in nighttime blood pressure (+0.5/+0.1 mm Hg) were observed at repeat recording. Reducing the sampling rate by 50% caused only a small impairment of the reproducibility indexes of both the average values and variability. Blood pressure reduction was greater during the first and last hours of the recordings, indicating an effect of the hospital environment on the between-monitoring difference. Changes in body weight (-0.7 kg, P = .006, at repeat recording) were related to those of 24-hour diastolic blood pressure (P < .05). In conclusion, patient reaction to medical environment and changes of body weight seem to account for most of the change in 24-hour blood pressure that occurs over a 3-month period.

[Clinical significance of blood pressure response to posture]

To assess the clinical significance of the blood pressure reaction to orthostatic posture, 55 normotensives and 369 subjects with different degrees of hypertension were studied with non-invasive 24-hour blood pressure monitoring. During the recordings blood pressure response to standing was evaluated at 8 a.m., and at 2, 4 and 7 p.m. All subjects were attributed a target organ damage score on the basis of ECG, chest x-ray and fundoscopic findings. To assess whether the orthostatic reaction may represent a marker for the severity of hypertension, subjects were divided into 4 classes of increasing blood pressure levels, and each class was further subdivided into two groups of subjects with orthostatic reaction above and below the mean value. On average, blood pressure rose by 2.7 +/- 9/7.2 +/- 7 mmHg while standing up, an increase which was inversely correlated to that of heart rate (p < 0.05). The orthostatic response was substantially constant throughout daytime hours. The systolic orthostatic change from lying to standing was directly correlated with age (p < 0.02) and average daytime blood pressure (p < 0.01), and inversely correlated with lying blood pressure immediately before standing up (p < 0.001). Both systolic (p < 0.05) and diastolic (p < 0.01) pressure responses to standing were related to the day-night blood pressure difference and to the standard deviation from mean daytime blood pressure. The degree of target organ damage was not significantly greater in the 4 groups of subjects with high orthostatic response compared to those with low response. The present results show that the pressure reaction to orthostatic stress is constant throughout daytime, even though a large intraindividual variability in the extent of the response is present. Orthostatic pressure change seems to be an important determinant of diurnal pressure rhythm, while it is not a marker for the severity of hypertension.

[Role of ophthalmoscopy in arterial hypertension: a problem revisited]

To evaluate the present role of fundal examination in the assessment of the hypertensive patient, 348 hypertensive subjects, mostly with borderline or mild hypertension, were studied with direct ophthalmoscopy. The exam was always performed by the same observer. The degree of left ventricular hypertrophy was also evaluated with ECG and echocardiography. Blood pressure was measured with 24-hour ambulatory monitoring, using either the Del Mar Avionics Pressurometer II and IV, the Spacelabs 5200 or the A & D TM-2420. Signs of hypertensive retinopathy were found in 51% of the subjects. The degree of retinopathy, defined according to a modified Keith-Wagener grading system, was highly correlated with average 24-hour mean blood pressure (r = 0.31; p less than 0.0001). Based on ECG, 16% of the subjects had left ventricular hypertrophy, while 23% showed an echocardiographic left ventricular mass, indexed by body surface area, above the normal limits. Left ventricular mass index was correlated with ambulatory blood pressure levels, but at a lower level of statistical significance (r = 0.19; p less than 0.001) compared to the degree of retinopathy. No correlation was found between 24-hour blood pressure and ECG findings. Ophthalmoscopy proved to be more sensitive than echocardiography and ECG in indexing 24-hour blood pressure load, while the specificity of the 3 exams was similar. The present data indicate that fundal examination is a sensitive indicator of the vascular consequences of increased blood pressure and is therefore useful in the assessment of the hypertensive patient, while the more expensive echocardiography is not of great clinical value in borderline and mild hypertension.