Monitoring of indoor bioaerosol for the detection of SARS-CoV-2 in different hospital settings.

Background: Spore Trap is an environmental detection technology, already used in the field of allergology to monitor the presence and composition of potentially inspirable airborne micronic bioparticulate. This device is potentially suitable for environmental monitoring of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in hospital, as well as in other high-risk closed environments. The aim of the present study is to investigate the accuracy of the Spore Trap system in detecting SARS-CoV-2 in indoor bioaerosol of hospital rooms. Methods: The Spore Trap was placed in hospital rooms hosting patients with documented SARS-CoV-2 infection (n = 36) or, as a negative control, in rooms where patients with documented negativity to a Real-Time Polymerase Chain Reaction molecular test for SARS-CoV-2 were admitted (n = 10). The monitoring of the bioaerosol was carried on for 24 h. Collected samples were analyzed by real-time polymerase chain reaction. Results: The estimated sensitivity of the Spore Trap device for detecting SARS-CoV-2 in an indoor environment is 69.4% (95% C.I. 54.3-84.4%), with a specificity of 100%. Conclusion: The Spore Trap technology is effective in detecting airborne SARS-CoV-2 virus with excellent specificity and high sensitivity, when compared to previous reports. The SARS-CoV-2 pandemic scenario has suggested that indoor air quality control will be a priority in future public health management and will certainly need to include an environmental bio-investigation protocol.

Ultrasound screening for asymptomatic deep vein thrombosis in critically ill patients: a pilot trial.

Deep vein thrombosis (DVT) in critically ill patients still represents a clinical challenge. The aim of the study was to investigate whether a systematic ultrasound (US) screening might improve the management of the antithrombotic therapy in intensive care unit (ICU). In this non-randomized diagnostic clinical trial, 100 patients consecutively admitted to ICU of the University Hospital of Perugia were allocated either in the screening group or in the control group. Subjects in the screening group underwent US examination of lower limbs 48 h after admission, and again after 5 days. Subjects in the control group underwent US examination according to the standard of care (SOC) of the enrolling institution. Retrospectively registered at ClinicalTrials.gov (NCT05019092) on 24.08.2021. Lower limb DVT was significantly more frequent in the screening group (p < 0.001), as well as the subsequent extension of a pre-existing DVT (p = 0.027). In the control group, DVT of large veins was more frequent (p = 0.038). Major bleedings were reported in 5 patients, 4 in the non-screening group and in 1 in the screening group. Patients in the screening group started the antithrombotic treatment later (p = 0.038), although the frequency, dose and duration of the treatment were not different between the two groups. The duration of stay in ICU was longer in the screening group (p = 0.007). Active screening for DVT is associated with an increased diagnosis of DVT. The screening could be associated with a reduced incidence of proximal DVT and a reduction in the bleeding risk.

Effects of structured home-based exercise training on circulating endothelial progenitor cells and endothelial function in patients with intermittent claudication.

INTRODUCTION: Exercise training improves walking capacity in patients with intermittent claudication (IC). Endothelial progenitor cells (EPCs), endothelial microparticles (EMPs), and endothelial dysfunction could play a role in this process. METHODS: We measured EPCs and EMPs in a group of 60 patients with IC, and in a control group of 20 individuals without IC, before a treadmill test and 2, 24, and 48 hours after the test. Thirty patients with IC were randomly assigned to perform a 12-week home-based exercise training program. The EPC count, flow-mediated dilation (FMD) of the brachial artery, pain-free walking time (PFWT), and maximum walking time (MWT) were measured at the baseline and after the exercise training program. RESULTS: In patients with IC, EMPs significantly increased 2 hours after the treadmill test, whereas EPCs significantly increased after 24 hours. Among the subjects assigned to complete the training program, we observed a significant increase in the number of EPCs after 12 weeks, as well as an improvement in FMD, PFWT, and MWT. A significant correlation between the variation of EPCs, FMD, and MWT was found. The increase of EPCs and FMD were independent determinants of the walking capacity improvement, without significant interaction. CONCLUSION: Our results suggest that EPCs mobilization contributes to the improvement of walking capacity in patients with IC undergoing structured physical training. A number of different, partly independent, mechanisms are involved in this process, and our results highlight the potential role of EMPs release and endothelial function improvement. ClinicalTrials.gov Identifier: NCT04302571.

Combined aerobic and resistance training improves microcirculation in metabolic syndrome.

BACKGROUND: Exercise intervention improves macrovascular function in metabolic syndrome (MeS) patients, but few studies have evaluated the effect of exercise on microcirculatory dysfunction, which plays a key role in the development of MeS and its correlated organ damage. We carried out this intervention study to evaluate the influence of an aerobic and resistance training on skin microvascular reactivity in MeS patients. METHODS: Postocclusive reactive hyperemia (PORH) of the forearm skin was evaluated, by laser-Doppler flowmetry, before and after a 12-week program of aerobic and resistance training in 15 MeS patients referring to our Lipid Metabolism Outpatients Clinic, together with anthropometric, fitness and metabolic parameters; 15 matched MeS patients who did not exercise, served as a control group. The exercise training consisted of 2 sessions/week of aerobic and resistant exercise. RESULTS: Following exercise program, we observed a significant reduction in body weight, fat mass, fasting blood glucose, serum HbA1c and triglycerides, while HDL-cholesterol significantly increased. The exercise-treated group experienced a significant improvement in the area of hyperemia (AH) after PORH, and in all fitness parameters: VO2max, strength on the pulldown lat machine, chest press, leg press and leg extension. A significant correlation emerged between the increase in AH and the reduction in HbA1c and between increase in AH and strength at the chest press, and at the leg extension. CONCLUSIONS: Our study showed that a short-term combined aerobic-resistance training positively affects microvascular reactivity in MeS patients. This improvement is correlated with the reduction of HbA1c and fitness parameters, and particularly with increased muscle strength at the upper and lower limbs.

Microcirculatory Improvement Induced by Laparoscopic Sleeve Gastrectomy Is Related to Insulin Sensitivity Retrieval.

AIMS: Microvascular dysfunction is a potential factor explaining the association of obesity, insulin resistance, and vascular damage in morbidly obese subjects. The purpose of the study was to evaluate possible determinants of microcirculatory improvement 1 year after laparoscopic sleeve gastrectomy (LSG) intervention. METHODS: Thirty-seven morbidly obese subjects eligible for bariatric surgery were included in the study. Post-occlusive reactive hyperemia (PORH) of the forearm skin was measured as area of hyperemia (AH) by laser-Doppler flowmetry before LSG and after a 1-year follow-up. RESULTS: After intervention, we observed a significant reduction in BMI, HOMA index, HbA1c, and a significant increase of AH in all patients after surgery; this variation was significant only in those patients having insulin resistance or prediabetes/diabetes. Although significant correlation between the increase of AH and the reduction of both BMI, HOMA index, and HbA1c was observed, BMI was the only independent predictor of AH variation after LSG at the linear regression analysis. CONCLUSIONS: Our study shows that LSG intervention is correlated with a significant improvement in the microvascular function of morbidly obese subjects; this improvement seems to be related to the baseline degree of insulin-resistance and to the retrieval of insulin-sensitivity post-intervention.

Relationships between global physical activity and bone mineral density in a group of male and female students.

BACKGROUND: Peak of bone mass (PBM) is generally reached about the age of 18 both in boys and girls. Maximizing PBM during growth may contribute to fracture risk reduction in adulthood and in the elderly. The aim of our study was to evaluate the effects on bone mineral density (BMD) of global physical activity (PA), carried out in the past 15 years, in a population of 70 healthy, young male and female subjects aged 22 to 25. METHODS: BMD of the lumbar spine and total hip was measured using dual-energy X-ray absorptiometry (DEXA); global PA, resulting from sports-related, occupational and commuting PA, was evaluated using validated questionnaires. RESULTS: Women spent more time than men both in sports-related, occupational and commuting PA in the age range between 10-15 years. In the female group global PA positively correlated with BMD of the lumbar spine (r=0.38; P=0.02) and the total hip (r=0.36; P=0.04) and BMD of the lumbar spine was independently predicted by global PA and Body Mass Index. CONCLUSIONS: Our retrospective cross-sectional study indicates that global PA, not only sports-related PA, performed during prepubertal age, is associated with a greater PBM in women.

Tolerability and efficacy of long-term treatment with daptomycin, ceftazidime and colistin in a patient with a polymicrobial, multidrug-resistant prosthetic joint reinfection: a case report.

INTRODUCTION: Prosthetic joint infections are severe complications of joint implants. Further complications arise when polymicrobial and/or multidrug-resistant microorganisms are involved. Currently, there are limited data on the management of these infections and on the tolerability of long-term treatment with daptomycin, ceftazidime and colistin. CASE PRESENTATION: A 55-year-old Caucasian woman who had a right hip prosthesis removed 1 year prior because of infection was admitted for prosthesis reimplantation. On admission at our hospital, anamnesis regarding etiology and management of prosthesis infection was not available. On clinical, laboratory findings and imaging studies infection was not suspected. A hip prosthesis was reimplanted. At surgery, histopathological and microbiological investigations were not taken. Three weeks after reimplantation, surgical site infection due to Enterobacter cloacae was diagnosed and oral ciprofloxacin was prescribed. Four days later, a periprosthesis fluid collection was evidenced and a percutaneous needle aspirate grew Staphylococcus epidermidis and S. haemolyticus. Enterobacter genome was also detected from the same sample. Teicoplanin and meropenem were added to ciprofloxacin without clinical improvement. Moreover, acetabular cup dislocation was documented. She underwent prosthesis explantation, debridement, and positioning of an antimicrobial mixed spacer. From the intraoperatory cultures S. epidermidis and Acinetobacter baumannii were grown. Daptomycin, ceftazidime, colistin and rifampin were administered. Four days later, rifampin was stopped due to a suspected liver toxicity. While undergoing therapy she presented recurrent episodes of wound dehiscence and on the 22nd week of treatment a further surgical debridement was performed, upon which the spacer was removed. At this time, intraoperative cultures resulted negative. Three months later, after a total of 8 months, antimicrobials were interrupted. Subsequently, a femoral transcondylar traction was positioned, and 3 weeks later a new prosthesis was reimplanted. At over 1 year after reimplantation she is well. CONCLUSIONS: Our findings suggest that microbiologic investigations are mandatory even when prosthetic joint infection is not suspected. Molecular methods for identification of microorganisms can be used in addition to conventional cultures especially when patients are under antibiotic treatment. Daptomycin, ceftazidime and colistin can be administered for several months without side effects. Guidelines specifically addressing the diagnosis and the management of polymicrobial, multidrug-resistant prosthetic joint infections need to be developed.

On-treatment C-reactive protein and HDL cholesterol levels in patients at intermediate cardiovascular risk: impact on carotid intima-media thickness.

AIMS: Statin therapy is followed by reductions in carotid intima-media thickness (CIMT) and C-reactive protein (CRP) levels, but a significant number of treated patients still have increased CIMT. We investigated whether on-treatment levels of CRP are associated with CIMT in hypercholesterolemic patients receiving statin therapy. The influence of blood pressure and anti-hypertensive therapy on the association between CRP and CIMT was evaluated. MAIN METHODS: The assessment of cardiovascular risk factors, CRP and CIMT, was performed in a cross-sectional study of 240 hypercholesterolemic patients at intermediate cardiovascular risk under statin therapy; 125 patients received only a statin (statin group) and 115 also anti-hypertensive therapy (combined therapy group). KEY FINDINGS: Logarithmically transformed CRP (ß=0.17, p=0.01) and HDL cholesterol levels (ß=-0.27, p<0.001) were correlates of CIMT, irrespective of confounders. High CRP levels (>3mg/L) were associated with a 2.7-fold increased risk of having high CIMT (>1.25mm). High CIMT was present in a high percentage of patients not at target for cholesterol and blood pressure levels (61%). Patients in the statin group had lower Framingham risk and CIMT than those in the combined therapy group. In the statin group, logarithmically transformed CRP (ß=0.28, p=0.004) and HDL cholesterol (ß=-0.21, p=0.03) were associated with CIMT. In the combined therapy group, HDL cholesterol was the only significant CIMT correlate (ß=-0.33, p=0.001). SIGNIFICANCE: On-treatment CRP and HDL cholesterol levels are associated with CIMT among hypercholesterolemic patients under statin therapy. In patients receiving both statin and anti-hypertensive therapy, HDL cholesterol remains the main covariate of CIMT.

Prognostic value of low and high ankle-brachial index in hospitalized medical patients.

BACKGROUND: Peripheral arterial disease (PAD) is frequently underdiagnosed in the clinical practice, leading to a lack of opportunity to detect subjects at a high risk for cardiovascular (CV) death. The ankle-brachial pressure index (ABI) represents a noninvasive, objective tool to diagnose PAD and to predict adverse outcome. METHODS: ABI was determined by means of Doppler velocimetry, in 707 patients, aged 50 years or older, consecutively hospitalized in an internal medicine ward, who were followed-up for at least 12 months in order to assess all-cause and CV mortality. RESULTS: Symptomatic PAD affected 8% of the population while the prevalence of PAD, defined as ABI <0.90, was 29%; high ABI (>1.40) was found in 8% of the patients. After a mean follow-up period of 1.6 years, both low and high ABI were independently associated with CV mortality with a hazard ratio of 1.99 (p=0.016) for low and 2.13 (p=0.04) for high ABI, compared with normal ABI (0.90-1.40). High ABI also independently predicted all-cause mortality with a hazard ratio of 1.77 (p=0.04). DISCUSSION: ABI measurement reveals a large number of individuals with asymptomatic PAD among those hospitalized in an internal medicine department. An increased mortality was observed in patients with both low and high ABI. Hospital admission for any reason may serve as an opportunity to detect PAD and start appropriate preventive actions.

Diagnostic performance of a multiple real-time PCR assay in patients with suspected sepsis hospitalized in an internal medicine ward.

Early identification of causative pathogen in sepsis patients is pivotal to improve clinical outcome. SeptiFast (SF), a commercially available system for molecular diagnosis of sepsis based on PCR, has been mostly used in patients hospitalized in hematology and intensive care units. We evaluated the diagnostic accuracy and clinical usefulness of SF, compared to blood culture (BC), in 391 patients with suspected sepsis, hospitalized in a department of internal medicine. A causative pathogen was identified in 85 patients (22%). Sixty pathogens were detected by SF and 57 by BC. No significant differences were found between the two methods in the rates of pathogen detection (P = 0.74), even after excluding 9 pathogens which were isolated by BC and were not included in the SF master list (P = 0.096). The combination of SF and BC significantly improved the diagnostic yield in comparison to BC alone (P < 0.001). Compared to BC, SF showed a significantly lower contamination rate (0 versus 19 cases; P < 0.001) with a higher specificity for pathogen identification (1.00, 95% confidence interval [CI] of 0.99 to 1.00, versus 0.94, 95% CI of 0.90 to 0.96; P = 0.005) and a higher positive predictive value (1.00, 95% CI of 1.00 to 0.92%, versus 0.75, 95% CI of 0.63 to 0.83; P = 0.005). In the subgroup of patients (n = 191) who had been receiving antibiotic treatment for ≥24 h, SF identified more pathogens (16 versus 6; P = 0.049) compared to BC. These results suggest that, in patients with suspected sepsis, hospitalized in an internal medicine ward, SF could be a highly valuable adjunct to conventional BC, particularly in patients under antibiotic treatment.

Cardiovascular risk factors and recommended lipid goals attainment among patients referred in a tertiary care lipid clinic.

BACKGROUND: Many adults are not at recommended lipid levels and the extent of treatment of dyslipidemia remains poor. We investigated the burden of cardiovascular risk and the distance of lipid fractions from the recommended targets by statin therapy and risk status in patients referred to a tertiary care lipid clinic. METHODS: Assessment of cardiovascular risk factors was performed in 1657 patients, mostly dyslipidemics, referred by family physicians to our Lipid Clinic, 393 patients being under statin therapy. The shortfall of lipid fractions from the National Cholesterol Education Program Adult Treatment Panel-III (NCEP ATP-III) recommended goals was evaluated. RESULTS: A high prevalence of cardiovascular risk factors was found. LDL cholesterol target was reached by 20% and 45% of untreated and statin treated patients, whereas non-HDL cholesterol target by 13% and 45% of untreated and statin treated patients, respectively. LDL cholesterol was over the goal by 27% in untreated patients and by 25% in statin treated patients. More than 40% and 65% statin treated patients were taking either a low statin dose or statins with low-to-moderate LDL cholesterol lowering efficacy (<30%). A decrease in the proportion of patients at target and greater shortfalls from recommended goals were found from low to high risk categories. CONCLUSION: The shortfall in reaching lipid targets, particularly among high risk statin untreated patients, may be partly explained by delayed or even inadequate lipid lowering therapy. Shortfalls in reaching the targets are not necessarily high and might be possibly managed at a primary care level.

Carotid intima-media thickness and bone turnover: the role of C-terminal telopeptide of type I collagen.

Osteoporosis and vascular disease are commonly found together in elderly people. Several common mechanisms and risk factors have been suggested to contribute to the development of osteoporosis and atherosclerosis. The present cross-sectional study was performed to determine whether the degree of bone turnover is correlated to carotid intima-media thickness (CCA-IMT), as a marker of subclinical atherosclerosis. We selected 50 outpatients (mean age 71.7 +/- 12.3), underwent to eco-Doppler evaluation of extracranial carotid tract, without history of calcium and/or vitamin D supplementation, or antireabsorptive therapy. CCA-IMT was measured by high-resolution B-mode ultrasonography. Bone turnover was evaluated by analysing serum levels of C-terminal telopeptide of type I collagen (sCTX), and bone-specific alkaline phosphatase. We also evaluated the vitamin D status by determination of the serum concentration of 25-hydroxyvitamin D [25(OH)D]. We found a prevalence of hypovitaminosis D [serum 25(OH)D levels <30 ng/mL, mean value 10.7 +/- 5.8] of 91.8%, and an increased bone resorption, with mean sCTX levels higher than reference values (mean 1.18 +/- 0.57 ng/mL). A significant positive correlation was found between CCA-IMT and age (r = 0.480, P = 0.001), erythrocyte sedimentation rate (ESR: r = 0.438, P = 0.001), high-sensitivity C-Reactive Protein (HsCRP: r = 0.482, P = 0.011), serum creatinine (r = 0.305, P = 0.031), and sCTX (r = 0.389, P = 0.006). In a multivariate linear regression, CCA-IMT was independently predicted by age (beta = 0.34, P = 0.001), ESR (beta = 0.37, P = 0.005), and sCTX (beta = 0.32, P = 0.006). The preliminary results of our study seem to indicate that after adjustment for established cardiovascular risk factors, sCTX independently predict an increased CCA-IMT in the elderly population.

Influence of short-term rosuvastatin therapy on endothelial progenitor cells and endothelial function.

Endothelial progenitor cells maintain endothelium integrity by replacing injured endothelial cells. Cholesterol-lowering promotes either endothelial progenitor cells mobilization or improves endothelial function. It is unknown whether improving endothelial function with statin is associated with a parallel increased endothelial progenitor cells availability. Thirty-two hypercholesterolemic patients were assigned to 4-week rosuvastatin (10 mg daily) and 16 hypercholesterolemic served as controls. Circulating endothelial progenitor cells, brachial artery flow-mediated vasodilatation, an index of endothelial function, and the lipid profile were measured before and after the 4-week statin therapy. At baseline, we found a correlation between circulating endothelial progenitor cells and flow-mediated vasodilatation (r = .31, P = .029). At the end of the 4-week intervention with rosuvastatin there was a 37% reduction in low-density lipoprotein cholesterol (P < .001) and a significant 72% increase in the number of endothelial progenitor cells and flow-mediated vasodilatation (4.7 + 0.7% to 8.8 + 0.4%, P < .001). Endothelial progenitor cells and flow-mediated vasodilatation were unchanged at the end of the study in patients not taking statin. A correlation emerged between endothelial progenitor cells and flow-mediated vasodilatation variations (r = .52, P < .001), this correlation being still significant after controlling for blood cholesterol reduction. In conclusion, short-term rosuvastatin therapy contributes in hyperchoelsterolemic patients to improving endothelial function by lowering cholesterol and increasing the number of circulating endothelial progenitor cells; the latter effect appears to be partly independent from reduction in plasma cholesterol.

The use of osteopathic manipulative treatment as adjuvant therapy in patients with peripheral arterial disease.

Peripheral arterial disease (PAD) is a manifestation of systemic atherosclerosis associated with impaired endothelial function and intermittent claudication is the hallmark symptom. Hypothesizing that osteopathic manipulative treatment (OMT) may represent a non-pharmacological therapeutic option in PAD, we examined endothelial function and lifestyle modifications in 15 intermittent claudication patients receiving osteopathic treatment (OMT group) and 15 intermittent claudication patients matched for age, sex and medical treatment (control group). Compared to the control group, the OMT group had a significant increase in brachial flow-mediated vasodilation, ankle/brachial pressure index, treadmill testing and physical health component of life quality (all p<0.05) from the beginning to the end of the study. At univariate analysis in the OMT group there was a negative correlation between changes in brachial flow-mediated vasodilation and IL-6 levels (r=-0.30; p=0.04) and a positive one between claudication pain time and physical function score (r=0.50; p=0.05). In conclusion, despite the relatively few patients in our study, these results suggest that OMT significantly improves endothelial function and functional performance in intermittent claudication patients along with benefits in quality of life. This novel treatment combined with drug and lifestyle modification might be an effective alternative to traditional training based on exercise.

Cervical spondylodiscitis with spinal epidural abscess caused by Aggregatibacter aphrophilus.

Spondylodiscitis caused by Aggregatibacter aphrophilus, formerly known as Haemophilus paraphrophilus, is an unusual condition and can be very difficult to diagnose. We report a case of cervical spondylodiscitis complicated by spinal epidural abscess in a 63-year-old woman, without underlying predisposing conditions. The source of infection was identified as a periodontal infection. The patient was successfully treated with systemic antibiotics.

Paraoxonase-1 activity modulates endothelial function in patients with peripheral arterial disease.

Human serum paraoxonase-1 (PON1) is thought to play a role in the favorable vascular effects of high-density lipoproteins, mainly through a reduction in low-density lipoprotein oxidation. Endothelial dysfunction, characterized by an impaired capacity of the arteries to dilate in response to a number of stimuli, represents the earliest stage of atherosclerosis. We performed the present study in 37 patients with peripheral arterial disease, with the aim of investigating the influence of PON1 Q192R polymorphism and activity on peripheral endothelial function, evaluated as brachial-artery flow-mediated vasodilation (FMV). Patients with the R allele (QR or RR genotype, n=19) had significantly higher PON1 activity [408 U/mL (309-456) versus 180 U/mL (141-243), p<0.001] and greater brachial FMV (5.7+/-3.9% versus 3.0+/-2.8%, p<0.001) than those with Q allele (QQ genotype, n=18). In the whole population, PON1 activity showed a direct relation to brachial FMV (r=0.46, p=0.004). In a multivariate linear regression analysis, the only independent predictors of brachial FMV were PON1 activity (beta=0.40, p=0.008), brachial-artery diameter (beta=-0.39, p=0.01) and male sex (beta=-0.27, p=0.04). These finding support the importance of PON1 activity as a modulating factor of the endothelial function.

Prognostic significance of isolated, non-specific left ventricular repolarization abnormalities in hypertension.

OBJECTIVE: Clinicians are often confronted with the incidental finding of isolated minor, non-specific repolarization changes on the electrocardiogram (ECG) in hypertensive patients. The aim of this study was to investigate the prognostic significance of such changes. DESIGN: Prospective, observational study. METHODS: A total of 1970 hypertensive patients without prevalent cardiovascular disease were followed for up to 9.1 years (mean 4.7 years). Patients with ECG abnormalities including ischaemia, previous infarction, bundle branch block, atrial fibrillation and ventricular pre-excitation were excluded. Patients were divided into three groups: normal left ventricular (LV) repolarization (n = 1355); minor repolarization changes (n = 504); and typical LV strain (n = 111). RESULTS: During follow-up, 78 patients developed new-onset ischaemic heart disease. The event rates were 0.50, 1.28 and 3.08 per 100 patient-years in the groups with normal repolarization, minor changes, and typical LV strain, respectively (P < 0.001). After adjustment for the effect of age, sex, diabetes, serum cholesterol, smoking, LV hypertrophy and 24-h pulse pressure, the risk for developing coronary events was higher in patients with minor repolarization changes (hazard ratio 2.07, 95% confidence interval 1.23-3.47; P < 0.01) or LV strain (hazard ratio 4.00, 95% confidence interval 2.09-7.65; P < 0.001) than in patients with normal repolarization (reference category). Population-attributable risks were 21 and 14%, respectively. Minor ST-T changes also retained an adverse prognostic value among patients without LV hypertrophy (hazard ratio 1.90, 95% confidence interval 1.08-3.33; P = 0.026). CONCLUSION: We have identified minor, non-specific LV repolarization changes as a novel, independent risk factor for ischaemic heart disease in patients with uncomplicated hypertension.

Capillary rarefaction and abnormal cardiovascular reactivity in hypertension.

OBJECTIVE: To determine the effects of capillary rarefaction on cardiovascular reactivity and microcirculatory functioning in essential hypertension. DESIGN: Hypertension is associated with abnormal cardiovascular reactivity and increased vasoconstriction. Capillary rarefaction amplifies these abnormalities, which modify microcirculatory hemodynamics. Hence this study of the hemorheological pattern and the veno-arteriolar reflex in hypertensive patients and normotensive control subjects. METHODS: Sixty-one men with never-treated essential hypertension and capillary rarefaction (< 80 capillaries per field) and 20 age-matched and sex-matched controls underwent a strenuous cycle ergometer test to monitor, during exercise and recovery, the blood pressure profile and the hemorheological pattern: blood viscosity at low shear, hematocrit and leukocyte counts, soluble P-selectin levels, and red and white blood cell filterability rates. The veno-arteriolar reflex was determined by laser-Doppler flowmetry before exercise and at recovery.RESULTS Hypertensive men with < or = 72 capillaries per field had an abnormal hemorheological profile before exercise. The physiological response to exercise was observed only in the controls and in hypertensives with > or = 73 capillaries per field. Abnormal responses to exercise worsened as capillaries were more rarefied. At recovery, hemorheological parameters in hypertensives with 65-72 capillaries per field returned to baseline, remaining significantly (P < 0.05) different to control values. Variations in the hemorheological pattern in hypertensives with < 64 capillary per field persisted at recovery. The veno-arteriolar reflex followed the same pattern. CONCLUSION: A reduced microvascular network may contribute to abnormal cardiovascular reactivity and to exercise-induced rheological abnormalities in hypertension.

The influence of iloprost on blood rheology and tissue perfusion in patients with intermittent claudication.

BACKGROUND: In peripheral vascular disease (PVD), impaired blood viscosity (BV) plays a major role in residual microvascular perfusion. Indeed, during acute leg ischaemia factors influencing microvascular BV include the plasma fibrinogen concentration, red and white blood cell rheology, as well as platelet aggregation and activation. AIM: To assess the effects of Iloprost in patients with PVD. METHODS: The effects of an infusion of a single dose of Iloprost (from 0.5 up to a maximum of 2 ng/kg/min. over 6 hours) in 16 patients with stage II peripheral vascular disease on blood rheology and tissue perfusion were determined in a double-blind placebo-controlled study, using repeated treadmill exercise test to stress leg circulation. Blood viscosity at low shear, soluble P-selectin levels (expression of platelet activation), unfractionated leukocyte and erythrocyte filterability rates, plasma fibrinogen concentration, haematocrit, leukocyte and platelet counts and transcutaneous oxygen pressure (TcPO(2)) were measured in two matched groups of 8 PVD patients before and after Iloprost infusion. RESULTS: Controlled peripheral ischaemia generated an impaired haemorheological profile; Iloprost reduced the impairments in BV and the filterability rates of unfractionated leukocytes and erythrocytes, inhibited platelet activation, and improved erythrocyte deformability. These changes were associated with significant shortening of the TcPO(2) half recovery time (the drop of TcPO(2) occurs because the ischaemic skeletal muscle steals oxygen from the skin), indicating that ischaemic damage had been contained. CONCLUSIONS: Our results show that the infusion of a single dose of Iloprost in patients with PVD is associated with a significant improvement in microvascular functioning