Targeted discovery proteomics to identify clinical phenotypes in heart failure with preserved ejection fraction: a proteomics substudy of VITALITY-HFpEF

Background

Heart failure with preserved ejection fraction (HFpEF) is a heterogenous syndrome that may emerge from overlapping systemic processes associated with several medical co-morbidities, often within an inflammatory milieu. Identification of unique proteins associated with distinct phenotypes may yield insight into novel therapeutics.

Purpose

Determine if unique clusters of circulating proteins are associated with specific clinical characteristics in patients with HFpEF.

Methods

A targeted discovery proteomics approach with 358 unique proteins associated with cardiovascular disease and inflammation (Olink) was used at baseline in VITALITY-HFpEF among 789 participants with documented left ventricular EF ≥45% and recent decompensation (<6 mos). Proteins were clustered applying the weighted correlation network analysis (WCNA). The associations of the clinical characteristics and frailty and clusters were estimated with linear regression adjusted for age and eGFR. Frailty was characterized as normal, pre-frail, and frail using the Fried criteria. KCCQ was the primary and 6-minute walk distance (6MWD) the secondary endpoint of VITALITY-HFpEF.

Results

Four unique clusters were identified containing 24, 66, 197, and 81 proteins, respectively. Figure 1 shows the adjusted association of the 4 protein clusters, shown with their hub proteins, with the clinical characteristics. The color (red: positive, green: negative relationship) and intensity indicate the magnitude of the standardized difference (relative to the variation [i.e., T-value]); p-value shown in boxes. Cluster 3, with tumor necrosis factor receptor 1 as a hub protein that mediates apoptosis and inflammation, was associated with greater frailty and physical limitation along with shorter 6MWD. In contrast, cluster 4, with protein C as a hub protein that regulates anticoagulation and exerts a protective function on endothelial cells, is associated with less frailty and younger age, and more frequently male sex. Cluster 2 was associated with only younger age and cluster 1 with no clinical characteristics.

Conclusions

Proteomics appear to identify specific clinical phenotypes associated with HFpEF. Further exploration of this approach may provide insight into the diverse pathophysiology characterizing this disorder and a more targeted approach to therapy.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): VITALITY-HFpEF was funded by Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA and Bayer AG, Wuppertal, Germany.

Geographic variation in heart failure with reduced ejection fraction: insights from the VICTORIA trial

Background

Geographic differences and background therapy have not been explored in the global VICTORIA trial, which enrolled high-risk patients with recent worsening heart failure with reduced ejection fraction (HFrEF).

Methods and results

Among 5050 patients enrolled in 5 pre-specified geographic regions, 34% were from Eastern Europe, 18% Western Europe, 23% Asia Pacific, 14% Latin and South America, and 11% North America (Table 1). Patients from Western Europe were older, had more atrial fibrillation, and lower glomerular filtration rates. Patients from Eastern Europe had more coronary artery disease and exhibited more advanced symptoms (∼50% New York Heart Association [NYHA] class III), whereas those from Latin and South America were less symptomatic (∼70% NYHA class II). North American patients had the largest body mass index as well as more diabetes and hypertension. Levels of NT-proBNP at randomization and MAGGIC risk scores were highest in Western European patients. Evidence-based triple medication therapy was used most frequently in Latin and South America and less frequently in North America; conversely, cardiac resynchronization therapy and implantable cardioverter defibrillators were most frequently used in North America and least frequently in Latin and South America. The overall primary composite event rate (cardiovascular death or HF hospitalization) in the placebo arm was 36.6/100 person-years over a median of 10.8 months and after adjusting for the MAGGIC score. When examined by region, these event rates were nominally highest in North America and lowest in Western Europe.

Conclusion

Substantial regional differences exist in characteristics and treatments among patients in this global trial of patients with HFrEF and a recent worsening event. These findings demonstrate the continuing unmet needs and opportunities for enhancing care in HFrEF.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): VICTORIA was funded by Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA and Bayer AG, Wuppertal, Germany.

The influence of status and the social environment on energy stores in a social fish

This study explores how muscle and liver energy stores are linked with social status and the social environment in Neolamprologus pulcher, a cooperatively breeding fish that lives in colonies comprised of up to 200 distinct social groups. Subordinate muscle energy stores were positively correlated with the number of neighbouring social groups in the colony, but this pattern was not observed in dominant N. pulcher. Furthermore, liver energy stores were smaller in dominants living at the edge of the colony compared with those living in the colony centre, with no differences among subordinates in liver energy stores. Subordinate N. pulcher may build up large energy stores in the muscles to fuel rapid growth after dispersal, which could occur more frequently in high-density environments. Dominant N. pulcher may use the more easily mobilized energy stores in the liver to fuel daily activities, which could be more energetically demanding on the edge of the colony as a result of the increased predation defence needed on the edge. Overall, this study demonstrates that both subordinate and dominant physiology in N. pulcher varies with characteristics of the social environment. Furthermore, dominant and subordinate energy storage strategies appear to differ due to status-dependent variation in daily activities and variation in the need to prepare for future reproductive or dispersal opportunities.

Consequences of experimental cortisol manipulations on the thermal biology of the checkered puffer (Sphoeroides testudineus) in laboratory and field environments

Anthropogenic climate change is altering temperature regimes for coastal marine fishes. However, given that temperature changes will not occur in isolation of other stressors, it is necessary to explore the potential consequences of stress on the thermal tolerances and preferences of tropical marine fish in order to understand the thresholds for survival, and predict the associated coastal ecological consequences. In this study, we used exogenous cortisol injections to investigate the effects of a thermal challenge on checkered puffers (Sphoeroides testudineus) as a secondary stressor. There were no significant differences between control and cortisol-treated fish 48h following cortisol treatment for swimming ability (using a chase to exhaustion protocol), blood glucose concentrations or standard metabolic rate. In the lab, control and cortisol-treated puffers were exposed to ambient (29.1±1.5°C), ambient +5°C (heat shock) and ambient -5°C (cold shock) for 4h and to evaluate the consequences of abrupt temperature change on puff performance and blood physiology. Following cold shock, control fish exhibited increases in cortisol levels and weak 'puff' performance. Conversely, fish dosed with cortisol exhibited consistently high cortisol levels independent of thermal treatment, although there was a trend for an attenuated cortisol response in the cortisol-treated fish to the cold shock treatment. A 20-day complementary field study conducted in the puffer's natural habitat, a tidal creek in Eleuthera, The Bahamas, revealed that cortisol-injected fish selected significantly cooler temperatures, measured using accumulated thermal units, when compared to controls. These results, and particularly the discrepancies between consequences documented in the laboratory and the ecological trends observed in the field, highlight the need to establish the link between laboratory and field data to successfully develop management policies and conservation initiatives with regards to anthropogenic climate change.

Disability in atypical parkinsonian syndromes is more dependent on memory dysfunction than motor symptoms

BACKGROUND

There is a gap in the systematic description and investigation of functional disability in corticobasal syndrome (CBS) and progressive supranuclear palsy (PSP). Additionally, the relations between disability, apraxia, cognitive and behavioural changes are not well understood in atypical parkinsonian syndromes.

METHODS

Fifty patients were included in this study (CBS = 18; PSP = 11), including a subgroup of primary progressive aphasia-nonfluent variant (PPA-nfv = 21) who were used as a control group given the clinic-pathological overlap. Functional disability (basic and instrumental activities of daily living), general cognition and behavioural changes were evaluated at baseline, with a subgroup of patients being reassessed after 16 months.

RESULTS

The corticobasal syndrome group had the most marked disability in basic activities in comparison to progressive supranuclear palsy and primary progressive aphasia-nonfluent variant. Longitudinal decline was marked for all three groups. In a linear regression examining factors behind functional disability in CBS and PSP, memory dysfunction emerged as the main factor (48.5%), followed by apraxia (14.9%) and atypical parkinsonian symptoms (9.6%).

CONCLUSIONS

Memory dysfunction is the most important factor in functional disability in CBS and PSP, which has to be taken into consideration in disease management, prognosis and planning of services to fully address patients' and families' needs.

Effect of nesiritide in patients with acute decompensated heart failure

BACKGROUND

Nesiritide is approved in the United States for early relief of dyspnea in patients with acute heart failure. Previous meta-analyses have raised questions regarding renal toxicity and the mortality associated with this agent.

METHODS

We randomly assigned 7141 patients who were hospitalized with acute heart failure to receive either nesiritide or placebo for 24 to 168 hours in addition to standard care. Coprimary end points were the change in dyspnea at 6 and 24 hours, as measured on a 7-point Likert scale, and the composite end point of rehospitalization for heart failure or death within 30 days.

RESULTS

Patients randomly assigned to nesiritide, as compared with those assigned to placebo, more frequently reported markedly or moderately improved dyspnea at 6 hours (44.5% vs. 42.1%, P=0.03) and 24 hours (68.2% vs. 66.1%, P=0.007), but the prespecified level for significance (P≤0.005 for both assessments or P≤0.0025 for either) was not met. The rate of rehospitalization for heart failure or death from any cause within 30 days was 9.4% in the nesiritide group versus 10.1% in the placebo group (absolute difference, -0.7 percentage points; 95% confidence interval [CI], -2.1 to 0.7; P=0.31). There were no significant differences in rates of death from any cause at 30 days (3.6% with nesiritide vs. 4.0% with placebo; absolute difference, -0.4 percentage points; 95% CI, -1.3 to 0.5) or rates of worsening renal function, defined by more than a 25% decrease in the estimated glomerular filtration rate (31.4% vs. 29.5%; odds ratio, 1.09; 95% CI, 0.98 to 1.21; P=0.11).

CONCLUSIONS

Nesiritide was not associated with an increase or a decrease in the rate of death and rehospitalization and had a small, nonsignificant effect on dyspnea when used in combination with other therapies. It was not associated with a worsening of renal function, but it was associated with an increase in rates of hypotension. On the basis of these results, nesiritide cannot be recommended for routine use in the broad population of patients with acute heart failure. (Funded by Scios; ClinicalTrials.gov number, NCT00475852.).

Using video simulated presence to reduce resistance to care and increase participation of adults with dementia

BACKGROUND

Cognitive and functional decline in dementia generally impairs performance of basic care activities. Staff assistance during these activities frequently results in confusion, anxiety, and distress, expressed through resistance to care (RTC).

METHODS

A single-system ABA withdrawal design (n = 1) evaluated the effect of video-simulated presence (VSP) for decreasing RTC and increasing participation. A family member pre-recorded videos for use during episodes of RTC, in which the family member spoke directly to the participant to encourage participation.

RESULTS

Introduction of the VSP significantly reduced RTC during the basic care tasks of feeding and talking medication. This effect was reversed when the intervention was withdrawn. Participation increased following VSP, demonstrating clear trends toward clinical significance.

CONCLUSIONS

This person-centered intervention, based on VSP of a family member, provides encouraging results for reducing RTC and increasing participation of adults with dementia in basic care tasks.

Biomechanical variables associated with Achilles tendinopathy in runners

OBJECTIVE

The aim of this study was to investigate the kinetics, kinematics and muscle activity in runners with Achilles tendinopathy.

DESIGN

Case-control study.

SETTING

Biomechanics laboratory.

PARTICIPANTS

21 runners free from injury and 21 runners with Achilles tendinopathy performed 10 running trials with standardised running shoes. Injured runners were diagnosed clinically according to established diagnostic criteria. Uninjured runners had been injury-free for at least 2 years.

MAIN OUTCOME MEASUREMENTS

During each trial, kinetic and lower limb kinematic data were measured using a strain gauge force plate and six infrared cameras respectively. Electromyographic (EMG) data from six muscles (tibialis anterior (TA), peroneus longus (PE), lateral gastrocnemius (LG), rectus femoris (RF), biceps femoris (BF) and gluteus medius (GM)) were measured with a telemetric EMG system.

RESULTS

Knee range of motion (heel strike to midstance) was significantly lower in injured runners than in uninjured runners. Similarly, preactivation (integrated EMG (IEMG) in 100 ms before heel strike) of TA was lower for injured runners than uninjured runners. RF and GM IEMG activity 100 ms after heel strike was also lower in the injured group. However, impact forces were not different between the two groups.

CONCLUSION

Altered knee kinematics and reduced muscle activity are associated with Achilles tendinopathy in runners. Rehabilitation exercises or other mechanisms (e.g. footwear) that affect kinematics and muscle activity may therefore be beneficial in the treatment of runners with Achilles tendinopathy.

Genetic variants of microsomal epoxide hydrolase and glutamate-cysteine ligase in COPD

The genetic factors that contribute to the development of chronic obstructive pulmonary disease (COPD) are poorly understood. Many candidate genes have been proposed, including enzymes that protect the lung against oxidative stress, such as microsomal epoxide hydrolase (EPHX1) and glutamate-cysteine ligase (GCL). To date, most reported findings have been for EPHX1, particularly in relation to functional variants associated with fast and slow metabolism of epoxide intermediates. The present study aimed to identify any association of variation in these genes with COPD susceptibility or severity. In total, 1,017 white COPD patients and 912 nondiseased age and sex matched smoking controls were genotyped for six single nucleotide polymorphisms (SNPs) in EPHX1 (including the fast and slow variants and associated haplotypes), and eight SNPs in the two genes encoding GCL. GCL is a rate-limiting enzyme in the synthesis of glutathione, a major contributor to anti-oxidant protection in the lung. No association of variation was found in EPHX1 or GCL with susceptibility to COPD or disease severity. This is the largest reported study to date and is well powered to detect associations that have been previously suggested. The current data indicate that these genetic variants are unlikely to be related to susceptibility or disease severity in white chronic obstructive pulmonary disease patients.

Improved surface EMG electrode for measuring genioglossus muscle activity

Activation of the genioglossus (GG) muscles is necessary to maintain the patency of the upper airway. In the condition of obstructive sleep apnea (OSA) this mechanism fails and the possible role of fatigue in its pathogenesis is still not fully understood. In this paper, a new electrode design for recording the genioglossus surface electromyogram (sEMG) is presented. The new design differs from a widely used GG surface electrode in both electrode configuration (unilateral rather than bilateral) and electrode material (Ag-AgCl rather than stainless steel (SS)). The separate effects of these factors were evaluated during force-varying and fatiguing contractions on normal human subjects and using GG sEMG model simulations. Unilateral sEMG was found to have lower amplitude, lower frequency content and a different rate of change of median frequency during fatiguing contractions. It was shown to overcome several disadvantages posed by the bilateral configuration and be more selective. Ag-AgCl has more favorable impedance characteristics and resulted in greater signal amplitudes. It was concluded that the new design is more suitable for detecting GG sEMG and allows more reliable interpretation of changes in sEMG due to physiological mechanisms, thus providing a new methodology for studying GG function and the role of fatigue in OSA.

Automatic detection of gait events using kinematic data

The timing of heel strike (HS) and toe off (TO), the events that mark the transitions between stance and swing phase of gait, is essential when analysing gait. Force plate recordings are routinely used to identify these events. Additional instrumentation, such as force sensitive resistors, can also been used. These approaches, however, include restrictions on the number of steps that can be analyzed and further encumbrance of the subject. We developed an algorithm which automatically determines these times from kinematic data recorded by a motion capture system, which is routinely used in gait analysis laboratories. The foot velocity algorithm (FVA) uses data from the heel and toe markers and identifies features in the vertical velocity of the foot which correspond to the gait events. We verified the performance of the FVA using a large data set of 54 normal children that contained both force plate recordings and kinematic data and found errors of (mean+/-standard deviation) 16+/-15 ms for HS and 9+/-15 ms for TO. The algorithm also worked well when tested on a small number of children with spastic diplegia. We compared the performance of the FVA with another kinematic method previously described. Our foot velocity algorithm offered more accurate results and was easier to implement than the previously described one, and should be applicable in a variety of gait analysis settings.

Estimation of selected heavy metals and arsenic in PM10 aerosols in the ambient air of the Greater Athens Area, Greece

Aerosol samples of PM(10) were collected during summer and winter 2003 at two different sites in the Messogia Basin northeast of Athens, to demonstrate the variations of heavy metals in PM(10) and examine their relationship with both gaseous pollutants and meteorological parameters. Estimated heavy metals during the experimental campaign were mercury (Hg), cadmium (Cd), lead (Pb), nickel (Ni) and arsenic (As). The average heavy metal concentrations for the first site (Spata) constituted 0.66-14.7ng/m(3) for the summer period and 0.14-19.5ng/m(3) for the winter period. At the second site (Koropi), the corresponding values varied between 0.89 and 13.3ng/m(3) and 0.16 and 24.7ng/m(3), respectively. PM(10) Hg, PM(10) Cd and PM(10) Ni contents showed regular daily variations, with higher mass percentages during the summer, indicating differences in local PM(10) sources for each season. On the contrary, PM(10) Pb presented higher mass percentages during the winter. Examination of the relationship between heavy metals and meteorological parameters indicated a higher correlation with temperature and relative humidity, especially for Pb. In addition, most of the heavy metals (apart from Hg) presented an expected correlation with nitrate oxides (NO(x)), PM(10) and ozone (O(3)). Higher correlations with both meteorological parameters and gaseous pollutants were observed during the winter experimental campaign. Maximum heavy metal concentrations at both sites were observed during days with NE or NNE prevailing winds during the summer campaign, while the winter period was characterized with maximums during days with W or WNW prevailing winds.

Design of surface electrode array for electromyography in the genioglossus muscle

The patency of the upper airway is dependent on the sustained activity of upper airway muscles, in particular the genioglossus (GG) muscles which act to protrude the tongue. Obstructive sleep apnea syndrome (OSAS) is a common and serious disorder in which this mechanism fails, resulting in frequent collapse of the airway during sleep. The properties of the upper airway muscles are therefore of interest in both normal and OSAS subjects, so that their role in the pathogenesis of OSAS can be better understood. Electromyography (EMG) is an important tool for assessing muscle activity and has been used in many GG studies. We have designed a new appliance incorporating a surface electrode array for GG EMG recording. The electrode configuration enables estimation of muscle fibre conduction velocity (CV), an important parameter for monitoring muscle fatigue, which has not been studied before in the GG. The appliance is also designed to provide accurate and repeatable placement of electrodes. Preliminary results presented demonstrate the performance of our appliance, which will now be used to measure GG CV in a range of fatiguing conditions.

Design of Surface Electrode Array for Measuring Conduction Velocity in the Human Genioglossus Muscle

A new appliance, incorporating linear arrays of pin electrodes for genioglossus (GG) surface electromyography measurement, is presented. This design enables the estimation of GG muscle fiber conduction velocity, which decreases with fatigue. The performance of the device was evaluated for ten healthy human subjects during fatiguing and force varying contractions.

Rhesus monkey rhadinovirus: a model for the study of KSHV

Rhesus monkey rhadinovirus (RRV) is one of the closest phylogenetic relatives to the human pathogen Kaposi sarcoma-associated herpesvirus (KSHV)-a gamma-2 herpesvirus and the etiologic agent of three malignancies associated with immunosuppression. In contrast to KSHV, RRV displays robust lytic-phase growth in culture, replicating to high titer, and therefore holds promise as an effective model for studying primate gammaherpesvirus lytic gene transcription as well as virion structure, assembly, and proteomics. More recently, investigators have devised complementary latent systems of RRV infection, thereby also enabling the characterization of the more restricted latent transcriptional program. Another benefit of working with RRV as a primate gammaherpesvirus model is that its efficient lytic growth makes genetic manipulation easier than that in its human counterpart. Exploiting this quality, laboratories have already begun to generate mutant RRV, setting the stage for future work investigating the function of individual viral genes. Finally, rhesus macaques support experimental infection with RRV, providing a natural in vivo model of infection, while similar nonhuman systems have remained resistant to prolonged KSHV infection. Recently, dual infection with RRV and a strain of simian immunodeficiency virus (SIV) has led to a lymphoproliferative disorder (LPD) reminiscent of multicentric Castleman disease (MCD)--a clinical manifestation of KSHV infection in a subset of immunosuppressed patients. RRV, in short, shows a high degree of homology with KSHV yet is more amenable to experimental manipulation both in vitro and in vivo. Taken together, these qualities ensure its current position as one of the most relevant viral models of KSHV biology and infection.

Sarcoidosis and MIF gene polymorphism: a case-control study in an Irish population

Macrophage migration inhibitory factor is a key pro-inflammatory mediator. A 5-CATT repeat functional polymorphism within the promoter of the gene was previously associated with the lowest promoter activity. It was hypothesised that patients exhibiting a 5-CATT allele would have a less aggressive inflammatory response with an associated less severe clinical phenotype in sarcoidosis. Irish Caucasian sarcoidosis patients (n = 173) followed up for 1-39 yrs and a control group (n = 166) were genotyped for the CATT repeat polymorphism. Disease severity at the time of diagnosis and at the time of elaboration of the present study was assessed by the presence of thoracic and extrathoracic symptoms, erythema nodosum, radiographic interstitial changes (chest radiograph score equal to stage II or greater, or high-resolution computed tomography confirmed), pulmonary function tests, steroid use, erythrocyte sedimentation rate, C-reactive protein and angiotensin-converting enzyme levels. In the Irish population studied, no evidence was found of a significant association between either sarcoidosis susceptibility and disease severity and the 5-CATT repeat functional polymorphism in the macrophage migration inhibitory gene. The present study found no significant association between the 5-CATT repeat macrophage migration inhibitory factor gene polymorphism and sarcoidosis, and did not support the overriding role for macrophage migration inhibitory factor in driving sarcoidosis pathogenesis.

Chorioamnionitis increases matrix metalloproteinase-8 concentrations in bronchoalveolar lavage fluid from preterm babies

OBJECTIVE

To determine the effects of chorioamnionitis and antenatal corticosteroids on matrix metalloproteinase-8 (MMP-8) concentrations in bronchoalveolar lavage (BAL) fluid from preterm babies in the first week of life.

DESIGN

Prospective observational study.

SETTING

Regional neonatal intensive care unit.

PATIENTS

Thirty five ventilated preterm babies < 33 weeks gestation, seven of whom were born after chorioamnionitis, which was diagnosed histologically as the presence of inflammatory cells in the chorioamnionic plate.

METHODS

MMP-8 was measured by enzyme linked immunosorbent assay (ELISA) in 90 serial BAL samples taken during the first six postnatal days. The median MMP-8 concentration for each baby was calculated.

RESULTS

Median MMP-8 concentrations were higher in the chorioamnionitis group than in those without (43 v 5 ng/ml). Partial or complete courses of antenatal corticosteroids had no effect on MMP-8 concentrations.

CONCLUSIONS

Higher concentrations of MMP-8 are found in BAL fluid from preterm babies from pregnancies complicated by chorioamnionitis. This type I collagenase may contribute to the lung injury that occurs in some babies with respiratory distress syndrome.

Selective serotonin reuptake inhibitors yield additional antiplatelet protection in patients with congestive heart failure treated with antecedent aspirin

Clinical depression has been identified as an independent risk factor for increased mortality in patients with coronary artery disease. Enhanced platelet activity has been suggested as the mechanism responsible for this adverse association. Selective serotonin reuptake inhibitors (SSRIs) are known to inhibit platelets in patients undergoing coronary stenting. We sought to determine whether concomitant therapy with SSRIs would yield additional anti-platelet benefit in patients with congestive heart failure (CHF) already treated with antecedent aspirin. A total of 88 patients with left ventricular ejection fraction (LVEF) <40% or CHF symptoms in the setting of preserved systolic function and NYHA Class II-IV were analyzed. Of these, 23 patients (26%) were chronic SSRI users (SSRI+), and 65 patients were free from SSRI therapy (SSRI-). All patients received aspirin (325 mg) for at least 1 month prior to platelet studies. Platelets were assessed by aggregometry, flow cytometry and a rapid analyzer. The SSRI+ group exhibited a substantial decrease in platelet activity when compared with SSRI- patients, as manifested by a significant reduction in ADP- (P=0.001), and collagen-induced (P=0.02) aggregation, and the expression of PECAM-1 (P=0.03), GPIb (P=0.03), GP IIb/IIIa antigen (P=0.02) and GP IIb/IIIa activity with PAC-1 antibody (P=0.04) and P-selectin (P=0.02). Therapy with SSRIs also resulted in the reduced formation of platelet-leukocyte microparticles (P=0.01). Epinephrine-induced aggregation in plasma, collagen-induced whole blood aggregation, closure time and expression of vitronectin receptor, CD63, CD107a, CD107b and CD151 did not differ between groups. In patients with CHF already on aspirin, SSRI therapy was associated with further inhibition of platelet function. This observation may help to explain some of the clinical benefits associated with SSRI therapy. Further clinical trials may help to elucidate the potential outcome benefits of SSRIs in other potential thrombotic circumstances.

Matrix metalloproteinases and tissue inhibitor of metalloproteinase-1 in sarcoidosis and IPF

The purpose of this study was to examine the role of interstitial collagenases, members of the family of matrix metalloproteinases, in the development of pulmonary fibrosis. The activity, levels and molecular forms of collagenases (matrix metalloproteinases (MMP)-1, -8 and -13), gelatinase B (MM P-9) and its main endogenous inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1) were assessed in bronchoalveolar lavage fluid (BALF) from patients with idiopathic pulmonary fibrosis (IPF) and sarcoidosis patients with varying degrees of pulmonary parenchymal involvement. Collagenase activity was elevated in IPF and group 3 sarcoidosis patients. A positive correlation between BALF collagenase activity and MMP-8 levels was also observed. Western immunoblotting revealed the presence of two isoforms of MMP-8 in patient samples; an 80 kD form representing latent enzyme from polymorphonuclear neutrophils and a 55 kD form representing the fibroblast-type proform. MMP-9 levels were also elevated in both IPF and group 3 sarcoidosis patients, while TIMP-1 levels remained normal, indicating a shift in the balance between the enzyme and inhibitor, favouring MMP-9. Matrix metalloproteinase-8 is the major contributor to the bronchoalveolar lavage fluid collagenase activity in the airways of patients with idiopathic pulmonary fibrosis and sarcoidosis and may initiate collagen destruction and remodelling leading to the development of pulmonary fibrosis.

Secretory leukocyte proteinase inhibitor and elafin are resistant to degradation by MMP-8

The naturally occurring neutrophil elastase inhibitors, alpha1-proteinase inhibitor (alpha1PI), secretory leukocyte proteinase inhibitor (SLPI), and elafin, are potential therapeutic agents in the treatment of neutrophil-mediated lung disease. However alpha1PI has been shown to be susceptible to inactivation by matrix metalloproteinases (MMPs) released by neutrophils, particularly neutrophil collagenase (MMP-8). The aim of this study was to determine if SLPI and elafin are similarly susceptible to degradation by this neutrophil-specific MMP. The effect of MMP-8 on SLPI and elafin was assessed by determining the neutrophil elastase inhibitory capacity (NEIC) and electrophoretic protein profile of both inhibitors following exposure to purified MMP-8. As a positive control, the effect of MMP-8 alpha1PI was assessed in parallel. Although treatment of alpha1PI with MMP-8 resulted in a significant decrease in its NEIC (P = .025), no similar decrease was observed with SLPI or elatin. Electrophoretic analysis confirmed digestion of alpha1PI by MMP-8 but no digestion of either SLPI or elafin was observed. These results demonstrate that SLPI and elafin are resistant to proteolytic inactivation by MMP-8, a property that may enhance their therapeutic application in neutrophil-mediated inflammatory lung disease.

The remarkable structural and functional organization of the eukaryotic pyruvate dehydrogenase complexes

The three-dimensional reconstruction of the bovine kidney pyruvate dehydrogenase complex (M(r) approximately 7.8 x 10(6)) comprising about 22 molecules of pyruvate dehydrogenase (E(1)) and about 6 molecules of dihydrolipoamide dehydrogenase (E(3)) with its binding protein associated with the 60-subunit dihydrolipoamide acetyltransferase (E(2)) core provides considerable insight into the structural and functional organization of the largest multienzyme complex known. The structure shows that potentially 60 centers for acetyl-CoA synthesis are organized in sets of three at each of the 20 vertices of the pentagonal dodecahedral core. These centers consist of three E(1) molecules bound to one E(2) trimer adjacent to an E(3) molecule in each of 12 pentagonal openings. The E(1) components are anchored to the E(1)-binding domain of the E(2) subunits through an approximately 50-A-long linker. Three of these linkers emanate from the outside edges of the triangular base of the E(2) trimer and form a cage around its base that may shelter the lipoyl domains and the E(1) and E(2) active sites. The docking of the atomic structures of E(1) and the E(1) binding and lipoyl domains of E(2) in the electron microscopy map gives a good fit and indicates that the E(1) active site is approximately 95 A above the base of the trimer. We propose that the lipoyl domains and its tether (swinging arm) rotate about the E(1)-binding domain of E(2,) which is centrally located 45-50 A from the E(1), E(2), and E(3) active sites, and that the highly flexible breathing core augments the transfer of intermediates between active sites.

Extension of the Drosophila lifespan by overexpression of a protein repair methyltransferase

Atypical protein isoaspartyl residues arise spontaneously during the aging process from the deamidation of protein asparaginyl residues and the isomerization of protein aspartyl residues. These abnormal residues are modified in cells by a strongly conserved protein carboxyl methyltransferase (PCMT) as a first step in a repair pathway. Because a decline in cellular repair mechanisms is hypothesized to contribute to senescence, we determined whether increased PCMT activity was correlated with enhanced longevity. Two ubiquitous promoters were used with the binary GAL4-UAS system to drive PCMT overexpression in Drosophila melanogaster. Flies expressing PCMT activity under the regulation of either the hsp70 or actin5C promoter had enzyme activities that were 3- or 7-fold higher, respectively, than control flies at 29 degrees C. Correlated with the observed increases in PCMT activities, such flies lived on average 32-39% longer than control flies. Lifespan extension was not observed at 25 degrees C with either hsp70- or actin5C-driven expression, indicating a temperature-dependent effect on longevity. We conclude that protein repair is an important factor in the determination of lifespan under certain environmental conditions. PCMT activity may become limiting under mild stress conditions that accelerate rates of protein damage.

Prognostic usefulness of the six-minute walk in patients with advanced congestive heart failure secondary to ischemic or nonischemic cardiomyopathy

Clinicians have relied on history and results from physical examinations to guide treatment of patients with advanced congestive heart failure, but these results may not reflect disease severity or hemodynamic status. We assessed how the distance walked in 6 minutes relates to clinical outcomes and symptoms of such patients. We compared the rates of death, hospitalization, and their composite at 1 year by the distance walked in 6 minutes at baseline and at 1 month, and by the change in distance between baseline and 1 month in 440 patients enrolled in a randomized trial. We also assessed the relations of baseline distance walked to symptom score and New York Heart Association class. The median distance increased from 218 m at baseline to 280 m at 1 month. Of 365 patients able to perform the baseline walk, 121 (33%) died and 217 (60%) were hospitalized compared with 46 (61%) and 34 (45%) of 75 patients unable to walk at baseline. Baseline distance significantly predicted mortality (hazard ratio 0.58/100-m increase, 95% confidence interval 0.50 to 0.68, p <0.001), even after adjustment. Baseline distance also significantly predicted hospitalization and the composite end point, as did the 1-month distance walked. The change in distance walked from baseline to 1 month did not predict any end point. Baseline distance correlated only moderately with symptom score (r = -0.385, p <0.001) and New York Heart Association class (r = -0.468, p <0.001). Distance walked during 6 minutes independently and strongly predicts mortality and hospitalization in patients with advanced congestive heart failure. This may be a simple, noninvasive, objective way to risk-stratify these patients and standardize their treatment.

The benefit of implementing a heart failure disease management program

BACKGROUND

To handle the increasing complexity of congestive heart failure (CHF) care, several new models for the care of patients with CHF have been developed to replace traditional strategies. We undertook this study to evaluate the potential benefit of implementing a CHF disease management program at a tertiary care center, particularly in terms of beta-blocker use and cost to the health care system.

METHODS

After reviewing the literature regarding therapies and management strategies for patients with CHF, we developed the Duke Heart Failure Program. All enrolled patients had 1 of the following: recent CHF hospitalization, ejection fraction less than 20%, or symptoms consistent with New York Heart Association class III or IV. We compared preenrollment and postenrollment medication use and resource utilization.

RESULTS

We enrolled 117 patients from July 1998 to April 1999. Mean enrollment time was 4.7 months. beta-Blocker use and dose significantly increased (52% vs 76% for beta-blocker, P<.01; 6% vs 13% of target dose, P<.01). The hospitalization rate decreased (1.5 vs 0 hospitalizations per patient-year, P<.01), while the number of clinic visits increased (4.3 vs 9.8 clinic visits per patient-year, P<.01). The Duke University Health System saved a median of $8571 per patient-year.

CONCLUSIONS

Implementing a CHF disease management program was associated with improved CHF medication dosing and with decreased hospitalization for patients with CHF. A CHF disease management program is an effective method for a health care system to care for patients with CHF.

Comparison of two aspirin doses on ischemic stroke in post-myocardial infarction patients in the warfarin (Coumadin) Aspirin Reinfarction Study (CARS)

The Coumadin Aspirin Reinfarction Study demonstrated that combination treatment with fixed dose warfarin (1 or 3 mg) + aspirin 80 mg was not superior to aspirin 160 mg alone after myocardial infarction for reducing nonfatal reinfarction, nonfatal stroke, and cardiovascular death. In this analysis, we examined the importance of aspirin dose in the protection against the secondary end point of ischemic stroke. The comparison arms for this analysis were warfarin 1 mg + aspirin 80 mg versus aspirin 160 mg. In the Coumadin Aspirin Reinfarction Study, 2,028 patients were randomized to aspirin 80 mg plus warfarin 1 mg, and 3,393 were randomized to aspirin 160 mg alone. A predictive model for ischemic stroke was developed using the Cox proportional-hazards model. A reduced Cox proportional-hazards model was developed to test for the effect of aspirin dose on ischemic stroke in predefined subgroups. The incidence of ischemic stroke was lower in patients treated with aspirin 160 mg than in patients treated with aspirin 80 mg + warfarin 1 mg (0.6% vs 1.1%; p = 0.0534). Age, previous stroke or transient ischemic attack, and aspirin dose were independent predictors of ischemic stroke. In addition, the highest risk patients, those with Q-wave myocardial infarction and male patients, appeared to receive greater benefit from aspirin 160 mg than from aspirin 80 mg + warfarin 1 mg. The results of this secondary analysis suggest that aspirin 160 mg is more effective than aspirin 80 mg + warfarin 1 mg in preventing ischemic stroke in post-myocardial infarction patients.

CD18 dependency of transendothelial neutrophil migration differs during acute pulmonary inflammation

Neutrophil extravasation during inflammation can occur either by a mechanism that requires the neutrophil integrin complex, CD18, or by an alternative CD18-independent route. Which of the two pathways is used has been shown to depend on the site and nature of the inflammatory insult. More recent evidence suggests that selection may also depend on whether inflammation is chronic or acute, but why this is the case remains unknown. Using an in vitro model that supports both migratory mechanisms, we examined the CD18 dependency of migration of neutrophils isolated from patients with either chronic or acute pulmonary infection. Chronic neutrophils were found to behave like normal neutrophils by migrating to IL-8 and leukotriene B(4) using the CD18-independent pathway, but to the bacterial product, FMLP, using the CD18-dependent route. In contrast, migration of acute neutrophils to all of these stimuli was CD18 dependent. Normal neutrophils could be manipulated to resemble acute neutrophils by exposing them to FMLP before migration, which resulted in a "switch" from the CD18-independent to -dependent mechanism during migration to IL-8 or leukotriene B(4). Although treatment of normal neutrophils with FMLP caused selective down-regulation of the IL-8 receptor, CXCR2, and acute neutrophils were found to have less CXCR2 than normal, a functional relationship between decreased CXCR2 and selection of CD18-dependent migration was not demonstrated. Results indicate that selection of the CD18-dependent or -independent migration mechanism can be controlled by the neutrophil and suggest that the altered CD18 requirements of acute neutrophils may be due to priming in the circulation during acute infection.

Inotropic therapy for heart failure: an evidence-based approach

BACKGROUND

Agents that increase cardiac contractility (positive inotropes) have beneficial hemodynamic effects in patients with acute and chronic heart failure but have frequently led to increased mortality when given on a long-term basis. Despite this fact, inotropes remain commonly used in the management of heart failure.

METHODS

We reviewed the available data on short- and long-term inotrope use in heart failure, emphasizing high-quality evidence on the basis of randomized trials that were powered to address clinical end points.

RESULTS

Available data suggest that long-term inotropic therapy has a negative impact on survival in patients with heart failure, regardless of the agent used. The data that inotropic therapy improves quality of life are mixed. High-quality randomized evidence is lacking for the use of inotropes for other heart failure indications, such as for acute decompensations or as a "bridge to transplant."

CONCLUSIONS

On the basis of the available evidence, the routine use of inotropes as heart failure therapy is not indicated in either the acute or chronic setting. Potentially appropriate uses of inotropes include as temporary treatment of diuretic-refractory acute heart failure decompensations or as a bridge to definitive treatment such as revascularization or cardiac transplantation. Inotropes also may be appropriate as a palliative measure in patients with truly end-stage heart failure. A model of heart failure pathophysiologic features that combines an understanding of both hemodynamic and neurohormonal factors will be required to best develop and evaluate novel treatments for advanced heart failure.

Relationship of depression to increased risk of mortality and rehospitalization in patients with congestive heart failure

BACKGROUND

Patients with congestive heart failure (CHF) may have a high prevalence of depression, which may increase the risk of adverse outcomes.

OBJECTIVE

To determine the prevalence and relationship of depression to outcomes of patients hospitalized with CHF.

METHODS

We screened patients aged 18 years or older having New York Heart Association class II or greater CHF, an ejection fraction of 35% or less, or both, admitted between March 1, 1997, and June 30, 1998, to the cardiology service of one hospital. Patients with a Beck Depression Inventory score of 10 or higher underwent a modified National Institute of Mental Health Diagnostic Interview Schedule to identify major depressive disorder. Primary care providers coordinated standard treatment for CHF and other medical and psychiatric disorders. We assessed all-cause mortality and readmission (rehospitalization) rates 3 months and 1 year after depression assessment. Logistic regression analyses were used to evaluate the independent prognostic value of depression after adjustment for clinical risk factors.

RESULTS

Of 374 patients screened, 35.3% had a Beck Depression Inventory score of 10 or higher and 13.9% had major depressive disorder. Overall mortality was 7.9% at 3 months and 16.2% at 1 year. Major depression was associated with increased mortality at 3 months (odds ratio, 2.5 vs no depression; P =.08) and at 1 year (odds ratio, 2.23; P =.04) and readmission at 3 months (odds ratio, 1.90; P =.04) and at 1 year (odds ratio, 3.07; P =.005). These increased risks were independent of age, New York Heart Association class, baseline ejection fraction, and ischemic etiology of CHF.

CONCLUSIONS

Major depression is common in patients hospitalized with CHF and is independently associated with a poor prognosis.

Cardiac rehabilitation and survival in patients with left ventricular systolic dysfunction

BACKGROUND

Exercise training, the major component of cardiac rehabilitation (CR), has been shown in previous trials to improve many pathophysiologic changes found in patients with left ventricular systolic dysfunction. It remains unproven whether exercise training improves survival.

METHODS

By using the Duke Databank for Cardiovascular Disease, we identified patients with an ejection fraction < or = 40% and no recent myocardial infarction, congenital heart disease, or primary valvular disease who survived > or = 30 days after a cardiac catheterization (n = 1902). Participation in CR (n = 70) was identified through computer billing records. We developed a multivariable Cox proportional hazards regression model to estimate survival by using variables known to be independent predictors of survival in patients with systolic dysfunction.

RESULTS

Patients participating in CR were less likely to be female or black and more likely to have a history consistent with ischemic cardiomyopathy. Participation in CR was associated with significantly improved survival after adjustment for baseline characteristics (hazard ratio, 0.39; 95% confidence interval, 0.15 to 0.62, P < .0001). Survival increased when patients participated in > 6 CR sessions (hazard ratio, 0.10; 95% confidence interval, 0.03 to 0.39; P < .0001).

CONCLUSIONS

Participation in CR was associated with improved survival for patients with cardiomyopathy. There appears to be a dose response with improved survival benefit for patients with left ventricular systolic dysfunction participating in cardiac rehabilitation.

Initiation of hormone replacement therapy after acute myocardial infarction is associated with more cardiac events during follow-up

OBJECTIVES

This study explored the association between the initiation of hormone replacement therapy (HRT) and early cardiac events (<1 year) in women with a recent myocardial infarction (MI).

BACKGROUND

Observational studies have linked postmenopausal hormone use with a reduced risk of death from heart disease. However, a recent randomized trial of HRT found no long-term benefit, primarily due to an increase in cardiac events in the first year.

METHODS

The Coumadin Aspirin Reinfarction Study (CARS) database contains information on HRT use and menopausal status for women with a recent MI. We classified the 1,857 postmenopausal women in CARS as prior/current HRT users if they took HRT before enrollment, new users if they began HRT during the study period or never users. We assessed the incidence of cardiac events (death, MI, unstable angina [UA]) during follow-up.

RESULTS

In our cohort, 28% (n = 524) used HRT at some point. Of these, 21% (n = 111) began HRT after their MI. New users had a higher incidence of death/MI/UA (41% vs. 28%, p = 0.001) during follow-up than never users, largely due to a higher incidence of UA (39% vs. 20%, p = 0.001). After adjustment, new users still had a significantly higher risk of death/MI/UA than never users during follow-up (relative risk [RR] = 1.44 [1.05-1.99]). Prior/current users had no excess risk of the composite end point after adjustment. Users of estrogen/progestin had a lower incidence of death/MI/UA during follow-up than users of estrogen only (RR = 0.56 [0.37-0.85]).

CONCLUSIONS

Postmenopausal women who initiated HRT after a recent MI had an increased risk of cardiac events largely due to excess UA during follow-up.

Hemodynamic profiles of advanced heart failure: association with clinical characteristics and long-term outcomes

BACKGROUND

Classifying patients with advanced congestive heart failure (CHF) by baseline measures of congestion and perfusion has been used to estimate hemodynamic status and to select and titrate therapy. We describe clinical characteristics of 4 hemodynamic profiles-wet/cold, wet/warm, dry/cold, and dry/warm-in patients with advanced CHF and assess relations between symptoms, physical signs, and outcomes with each profile.

METHODS AND RESULTS

We retrospectively assessed baseline symptoms, physical-examination variables, and 1-year outcomes of 440 patients in a randomized trial. With univariable and multivariable logistic regression, we examined relations of physical-examination variables to hemodynamic profiles. We also assessed the rates of death and death or readmission by profile. Severity of CHF symptoms did not predict the wet-versus-dry profile or cold-versus-warm status, despite significant differences in hemodynamics among groups. Of the physical-examination variables, only a lower proportional pulse pressure was a significant multivariable predictor of the wet category. Among wet patients (n = 348), this same variable was the only significant multivariable predictor of the cold category. For dry patients (n = 92), the cold category was predicted in multivariable analysis by supine heart rate and hepatomegaly. Survival was similar among profiles: wet/cold, 54.2% (n = 91); wet/warm, 58.3% (n = 105); dry/cold, 78.9% (n = 15); and dry/warm, 67.1%, P =.13 (n = 49). Event-free survival also was similar among profiles: wet/cold, 22.0% (n = 37); wet/warm, 29.4% (n = 53); dry/cold, 42.1% (n = 8); and dry/warm, 31.5%, P =.44 (n = 23).

CONCLUSIONS

The patient's history and physical examination alone may lead to inaccurate estimation of hemodynamic status and thus suboptimal management for patients with advanced CHF.

Type I collagenases in bronchoalveolar lavage fluid from preterm babies at risk of developing chronic lung disease

OBJECTIVE

To assess whether increased collagenolysis precedes severe chronic lung disease (CLD).

METHODS

Matrix metalloproteinase-1 (MMP-1) and MMP-8 (enzymes that degrade type I collagen, the main structural protein of lung extracellular matrix) were measured by enzyme linked immunosorbent assay in 100 bronchoalveolar lavage samples taken during the first 6 postnatal days from 45 ventilated preterm babies < 33 weeks gestation. The median value for each baby was calculated. CLD was defined as an oxygen requirement after the 36th week after conception.

RESULTS

MMP-8 levels in bronchoalveolar lavage fluid were higher (median 13 ng/ml) in 20 babies who developed CLD than in 25 without CLD (median 2 ng/ml). No MMP-1 was detected in any sample.

CONCLUSIONS

MMP-8 can be detected in bronchoalveolar lavage fluid from preterm babies, and higher levels are found in those who later develop CLD. MMP-8 may contribute to lung injury that occurs as a prelude to CLD.

Platelet inhibition by sertraline and N-desmethylsertraline: a possible missing link between depression, coronary events, and mortality benefits of selective serotonin reuptake inhibitors

Recently, clinical depression has been identified as an independent risk factor for increased mortality in patients following acute coronary events. Although the underlying mechanisms of this link remain uncertain, increased platelet activity has been suggested but never proven as the mechanism responsible for this association. Sertraline hydrochloride is a selective serotonin reuptake inhibitor (SSRI), and is an effective antidepressant agent. Its major liver metabolite, N-desmethylsertraline (NDMS), is known to be neurologically inactive. We assessed the in vitro effects of escalating concentrations of sertraline and NDMS on human platelets by aggregometry in plasma and whole blood, by expression of major surface receptors with flow cytometry in washed cells and in the whole blood, and quantitatively by various platelet function analysers in healthy volunteers and patients with coronary artery disease. Pretreatment of blood samples with sertraline and NDMS resulted in a dose-dependent inhibition of platelet-rich plasma aggregation induced by 5 microM ADP (P =, 0.002), by 10 microM ADP (P = 0.0017), by collagen (P = 0.008), and by thrombin (P = 0.026). Whole blood platelet aggregability was also significantly reduced when induced by 20 microM ADP (P = 0.006), and by collagen (P = 0.01). Surface expression of CD9 (P = 0.004), GP Ib (P = 0.0001), GP IIb/IIIa (P = 0.007), VLA-2 (P = 0.01), P-selectin (P = 0.02), and PECAM-1 (P = 0.01), but not the vitronectin receptor, was also reduced in sertraline and NDMS pretreated washed platelets. Whole blood flow cytometry revealed significant inhibition of GP IIb/IIIa (P = 0.008), and P-selectin expression (P = 0.0001) in NDMS treated samples. Closure time was delayed for the collagen-ADP cartridge (P = 0.009), and for the collagen-epinephrin cartridge (P = 0.01), indicating platelet inhibition in whole blood under high shear conditions. Rapid platelet-function assay revealed a decreased (P = 0.002) ability of platelets to agglutinate fibrinogen-coated beads, suggesting GP IIb/IIIa inhibition. Both sertraline, and its neurologically inactive metabolite NDMS, exhibited significant dose-dependent inhibition of human platelets. The documented anti-platelet effects of sertraline and NDMS may be directly related to the mortality benefits of SSRIs after ischemic events including myocardial infarction and stroke.

An alpha1-antitrypsin enhancer polymorphism is a genetic modifier of pulmonary outcome in cystic fibrosis

Lung disease is the direct cause of death in over 90% of cystic fibrosis (CF) patients. Excess neutrophil elastase is an important determinant of pulmonary disease in CF. alpha1-antitrypsin (AAT), also known as alpha1-proteinase inhibitor (alpha1PI) is a major modulator of elastase activity. We investigated the hypothesis that an enhancer polymorphism in the AAT gene would contribute to pulmonary prognosis in CF. Respiratory function, chest X-ray scores, bacterial colonisation and infective exacerbation were assessed to evaluate pulmonary disease severity in the CF group. Sixteen patients were found to have the 1237A allele, and 108 the more frequent G allele. Contrary to expectation, the patients with the 1237A allele were found to have better indices of pulmonary disease progression than those without, as indicated by less change in X-ray score (1237A: 0.2+/-0.1; 1237G: 1.2+/-0.1; P = 0.002) and fewer infective exacerbations (1237A: 2.8+/-0.6; 1237G: 4.6+/-0.3; P = 0.03) over the preceding 2 years. Also, a higher proportion of the 1237A (25%) than the 1237G (6.5%) were not colonised by Pseudomonas Aeruginosa (P = 0.04). Prospective monitoring of infections for a further 2 years confirmed a lesser propensity to infection in patients with the 1237A allele. These trends were also observed in a tightly matched sub-set of CF genotypes of similar age and sex, thus confirming that these effects were independent of the CF genotype. These results indicate that this AAT enhancer polymorphism is associated with better pulmonary prognosis in CF. Though the number of CF patients with the polymorphism is small, and these data need to be confirmed in larger studies, they suggest that a cautious approach should perhaps be taken to treatment of CF patients with supplemental AAT.

Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE): design and rationale

BACKGROUND

There is little information about how to adjust pharmacologic agents in the treatment of patients with advanced congestive heart failure (CHF). Some studies have suggested that use of pulmonary artery catheterization to guide reductions in filling pressures may improve outcomes for patients with heart failure who are hospitalized with evidence of elevated filling pressures. However, there is no consensus regarding the true utility of this strategy. A randomized clinical trial is needed to test the safety, efficacy, and treatment benefit of pulmonary artery catheterization in patients with advanced CHF.

STUDY DESIGN

The Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial is a multicenter, randomized trial designed to test the long-term safety and efficacy of treatment guided by hemodynamic monitoring and clinical assessment versus that guided by clinical assessment alone in patients hospitalized with New York Heart Association class IV CHF. Five hundred patients will be randomly assigned to receive either medical therapy guided by a combination of clinical assessment and hemodynamic monitoring (PAC arm) or medical therapy guided by clinical assessment alone (CLIN arm). The primary end point of ESCAPE will be the number of days that patients are hospitalized or die during the 6-month period after randomization. Secondary end points will include changes in mitral regurgitation, peak oxygen consumption, and natriuretic peptide levels. Other secondary end points will be pulmonary artery catheter-associated complications, resource utilization, quality of life measures, and patient preferences regarding survival.

IMPLICATIONS

The primary goal of ESCAPE will be to provide information about the utility of the pulmonary artery catheter in patients with advanced heart failure, independent of various treatment approaches used by individual physicians. In addition, this study will define current outcomes for this severely compromised population.

Clinical utility of the platelet function analyzer (PFA-100) for the assessment of the platelet status in patients with congestive heart failure (EPCOT trial)

BACKGROUND

Data from small studies have shown the presence of platelet abnormalities in patients with congestive heart failure (CHF). We sought to characterize the diagnostic utility of platelet function analyzer (PFA-100) in the CHF population.

METHODS

Blood samples were obtained for measurement of adenosine diphosphate (ADP)/collagen and epinephrine/collagen shear-induced closure time (CT), whole blood aggregation, platelet contractile force, activity of glycoprotein (GP) IIb/IIIa, and P-selectin receptors in 100 consecutive outpatients with CHF.

RESULTS

Substantial interindividual variability of platelet characteristics exists in patients with CHF. There were no statistically significant differences when patients were divided by the incidence of vascular events, emergency revascularization needs, survival, or etiology of heart failure. Aspirin use did not affect instrument readings as well. CT correlates well with whole blood aggregometry (r(2)=.587) and less with GP IIb/IIIa activity (r(2)=.326). No correlation has been observed for the CT with the platelet-bound P-selectin (r(2)=.041) and platelet contractile force measures (r(2)=.028).

CONCLUSIONS

PFA-100 is indeed capable to serve as a platelet analyzer and may be successfully used as a screening device. However, patients with heart failure enrolled in the EPCOT trial exhibited a marginal, sometimes oppositely directed changes in the platelet function, challenging the diagnostic utility of PFA-100 to serve as a useful tool for the identification of platelet abnormalities, predicting clinical outcomes, or for the monitoring of antiplatelet strategies in this population.

Relation of soluble and platelet P-selectin to early outcome in patients with acute myocardial infarction after thrombolytic therapy

Pre- and post-treatment platelet and soluble P-selectin were measured in a group of patients enrolled in the GUSTO-III study and were correlated with clinical outcomes. A peak in soluble P-selectin levels at 3 hours after thrombolytic therapy and lower baseline platelet P-selectin were associated with successful thrombolysis.

Rational use of inotropic therapy in heart failure

Despite their theoretic appeal, agents that increase cardiac contractility (positive inotropes) have consistently been shown to increase mortality when given chronically to patients with heart failure. The routine use of inotropes as heart failure therapy in either the acute or the chronic setting is not supported by the available data. Some appropriate uses of inotropes are as temporary treatment of diuretic-refractory acute heart failure decompensations, or as a bridge to definitive treatment such as revascularization or cardiac transplantation. Although controversial, the use of inotropes as a palliative measure in the small subset of patients with truly end-stage heart failure may be appropriate. An understanding of the appropriate goals of therapy is important for both patients and physicians if rational decisions about the use of inotropes are to be made.

[Calcium antagonists in the treatment of heart failure. Re-evaluation of therapeutic strategies]

The pharmacological management of heart failure has evolved during the last decade from therapies focused on improving haemodynamics to others that modulate neurohormonal systems which are activated in the setting of left ventricular dysfunction. Despite optimal inhibition of these systems with drugs such as ACE inhibitors, beta-blockers, digoxin and, most recently, spironolactone, the mortality rate remains unacceptably high. Calcium antagonists have long been investigated for use in a variety of cardiovascular diseases, including ischaemic heart disease, hypertension, and heart failure. However, concern has arisen with regard to the use of calcium antagonists in the treatment of left ventricular dysfunction--particularly those agents with negative inotropic activity. In addition, first generation dihydropyridines have also generated concern because of their profound vasodilatory effects and the fact that they have been shown to increase noradrenaline (norepinephrine) levels and neurohormonal activity. The third generation dihydropyridine calcium antagonists appear to be more promising therapies for heart failure, given their pharmacological properties of higher vascular selectivity and their minimal effects on neurohormonal activation. Several trials have been conducted with third generation dihydropyridines and additional trials are ongoing. A new class of calcium antagonists, which blocks the T-type calcium channel, was introduced in 1998. The prototype drug, mibefradil, was rigorously tested for use in heart failure in the Mortality Assessment in Congestive Heart Failure (MACH-1) trial. It was expected that calcium antagonists blocking the T-type calcium channel would be of benefit, because of their lack of negative inotropic effects and their ability to induce regression of hypertrophy. The results of the MACH-1 trial were disappointing, and the trial was prematurely discontinued as a result of excess mortality in the mibefradil arm. The purpose of this review is to examine the evidence-based pharmacotherapeutic strategies in the management of heart failure, and to discuss current and potential roles for calcium antagonists in the therapeutic regimen.

Clinical characteristics and long-term outcomes of patients with heart failure and preserved systolic function

Although the syndrome of heart failure with preserved systolic function may occur in up to 40% of all heart failure patients, the clinical, angiographic characteristics, and long-term outcomes of these patients are poorly understood. We prospectively evaluated 2,498 consecutive patients with New York Heart Association class II to IV symptoms and ejection fractions of >40%, who underwent cardiac catheterization between January 1984 and December 1996 at Duke University Medical Center. The median age for the entire cohort was 63 years; 25% of the population was >71 years old. In addition, 55% of the patients were women, 65% had ischemic heart disease, 28% had a history of diabetes, and 62% had a history of hypertension. The median ejection fraction was 58%. One third of the patients had multivessel disease by coronary angiography. The overall 5-year mortality of the total population was 28%. The independent predictors of mortality (p <0.05) using a multivariable Cox proportional hazard model were age, class IV symptoms, ejection fraction, coronary artery disease index, diabetes, peripheral vascular disease, and minority ethnic group. Heart failure with preserved systolic function is characterized by unique clinical and angiographic characteristics associated with a 5-year mortality rate of 28%. Furthermore, several clinical and angiographic characteristics are predictive of long-term survival.

A polymorphism in the tumor necrosis factor-alpha gene promoter region may predispose to a poor prognosis in COPD

STUDY OBJECTIVES

To determine whether the adenine (A)-guanine (G) substitution polymorphism at position - 308 on the tumor necrosis factor-alpha gene confers susceptibility to COPD or to the development of a more severe form of disease.

DESIGN

A cross-sectional study was undertaken to compare the frequency of the A allele in a group of 106 patients with COPD with that in a control population (n = 99). Patients were followed up prospectively for a period of 2 years.

PARTICIPANTS AND SETTING

Participants included 106 COPD patients recruited from a respiratory outpatient clinic and 99 control subjects recruited from patients admitted for cardiac catheterization.

MEASUREMENTS AND RESULTS

DNA was extracted from venous blood, and each subject was genotyped for the polymorphism by polymerase chain reaction amplification and restriction digestion using Nco1. There was no increased frequency of the A allele in patients compared to control subjects. AA homozygous patients had less reversible airflow obstruction (p<0.05) and a significantly greater mortality (both all-cause and respiratory deaths) on follow-up (p<0.001), despite a shorter cigarette smoking history.

CONCLUSIONS

This study suggests that homozygosity for this A allele predisposes to more severe airflow obstruction and a worse prognosis in COPD.

Investigation of vascular endothelial growth factor effects on pulmonary endothelial monolayer permeability and neutrophil transmigration

This study sought to determine whether vascular endothelial growth factor (VEGF)-induced permeabilisation of pulmonary endothelium to macromolecules could be related to a permissive role for neutrophil-derived VEGF in neutrophil transmigration. Treatment of human pulmonary artery endothelial cell (HPAEC) monolayers with 1, 10 or 100 ng/ml VEGF for 15 min or 1, 10 ng/ml for 90 min significantly increased endothelial permeability to trypan blue-labelled albumin (TB-BSA). These increases were correlated with changes in the cellular distribution of F-actin, as visualised by rhodamine-phalloidin staining: increased stress fibre formation, cellular elongation and formation of intercellular gaps after 15 min; at 90 min, there was also evidence of microspike formation and extension of spindle processes from the cell surface. Treatment of human neutrophil suspensions with 200 nM phorbol myristyl acetate (PMA), n-formyl-methionyl leucylphenylalanine (fMLP, 10 nM), interleukin-8 (IL-8, 10 nM) (but not with leukotriene B(4) (LTB(4)) 100 nM), for 30 min caused significant extracellular release of neutrophil VEGF stores. A permissive role for neutrophil-derived VEGF in facilitating migration across HPAEC monolayers was assessed in experiments using a functional blocking antihuman VEGF antibody. In the presence of this antibody (10 microg/ml), neutrophil migration in response to fMLP (10 nM), IL-8 (10 nM) or LTB(4) (100 nM) was not significantly different to that in the absence of antibody. We conclude that neutrophil-derived VEGF does not play a functional role in facilitating neutrophil migration across pulmonary vascular endothelium, despite its ability to induce cytoskeletal changes and enhance endothelial macromolecular permeability.

Hemostatic abnormalities in patients with congestive heart failure: diagnostic significance and clinical challenge

Knowledge of the pathogenesis of congestive heart failure (CHF) has improved greatly in recent years. However, this disease continues to cause one of the highest morbidities and mortalities in the Western world. The pathophysiology of heart failure is complex and much of our understanding revolves strictly around the neurohormonal mechanisms involved. Various pharmacologic interventions have significantly improved morbidity and include ACE inhibitors, beta-blockers, diuretics, and inotropic agents. Yet, no consensus has been reached regarding the use of anticoagulants or antiplatelet agents. It has been suggested that CHF is associated with altered hemostasis, but whether this prothrombotic state contributes to the pathogenesis and progression of the disease is unknown. The purpose of this review article is to discuss our current knowledge of platelet activation, thrombin generation, fibrinolysis, and endothelial dysfunction in CHF patients, and the potential role of anticoagulants and/or antiplatelet agents in preventing these hemostatic abnormalities.

Interleukin-8 and leukotriene-B(4), but not formylmethionyl leucylphenylalanine, stimulate CD18-independent migration of neutrophils across human pulmonary endothelial cells in vitro

Although neutrophil migration from the systemic circulation involves the beta2- (or CD18) integrin family, the existence of an alternative, CD18-independent route of neutrophil extravasation to tissues has been demonstrated in animal models. The molecular interactions involved in this alternative migratory route have not yet been characterized. The objective of this study was to assess the CD18-dependency of neutrophil migration across human endothelial cells from an organ known to support CD18-independent migration, the lung, with a view to establishing an in vitro model to facilitate study of CD18-independent migration. Neutrophil migration across human pulmonary artery endothelial cells (HPAECs) in response to three different chemoattractants, formylmethionyl leucylphenyl-alanine (FMLP), interleukin (IL)-8, and leukotriene (LT) B(4), was examined. Results demonstrated that a function-blocking antibody to CD18 decreased FMLP-stimulated migration by 71.7 +/- 4.4% (P < 0.001). In contrast, migration in response to LTB(4) was decreased by only 20.5 +/- 10.2% (P < 0.01), and no significant decrease was observed with migration to IL-8. Neutrophils that migrated to FMLP had 1.7-fold more surface CD11b/CD18 compared with nonmigrated neutrophils (P < 0.01), whereas this integrin complex was not significantly upregulated on neutrophils that had migrated to IL-8 or LTB(4). Further investigation of this migratory route indicated that it did not involve the beta1 integrins (CD29) or the endothelial selectins, E- or P-selectin, nor did it require the activity of either metalloproteinases or neutrophil elastase. These results indicate that neutrophil migration across HPAECs in vitro to IL-8 and LTB(4) is predominantly CD18-independent and provides a much-needed in vitro system for examination of the neutrophil-endothelial interactions involved in this alternative migratory route.

Circadian rhythm and sudden death in heart failure: results from Prospective Randomized Amlodipine Survival Trial

OBJECTIVE

The purpose of this study was to address the timing of sudden death in advanced heart failure patients.

BACKGROUND

Sudden death is a catastrophic event in cardiovascular disease. It has a circadian pattern prominent in the early AM, which has been thought to be due to a surge of sympathetic stimulation. We postulated that the distribution of events in advanced heart failure, with chronic sympathetic activation, would be more uniform implicating other potential mechanisms.

METHODS

We analyzed data from Prospective Randomized Amlodipine Survival Trial (PRAISE). Sudden deaths were analyzed by time of death in 4-h and 1-h blocks for uniformity of distribution in the entire cohort, and in the prespecified ischemic and nonischemic stratum. Further analyses were undertaken in the treatment groups of amlodipine and placebo, and among those receiving background therapy of aspirin and warfarin.

RESULTS

Sudden deaths in the overall cohort showed a nonuniform distribution with a PM peak but not an AM peak. The ischemic stratum also showed a PM peak, but sudden deaths within the nonischemic stratum were uniformly distributed. Neither amlodipine treatment nor aspirin or warfarin use altered the distribution.

CONCLUSIONS

Sudden death in advanced heart failure did not show an AM peak, suggesting that circadian sympathetic activation did not strongly influence these events. The PM peak noted is likely complex in origin and was not affected by antiischemic or antithrombotic medications.

Ca2+-free calmodulin and calmodulin damaged by in vitro aging are selectively degraded by 26 S proteasomes without ubiquitination

The ubiquitin-proteasome pathway is believed to selectively degrade post-synthetically damaged proteins in eukaryotic cells. To study this process we used calmodulin (CaM) as a substrate because of its importance in cell regulation and because it acquires isoaspartyl residues in its Ca(2+)-binding regions both in vivo and after in vitro "aging" (incubation for 2 weeks without Ca(2+)). When microinjected into Xenopus oocytes, in vitro aged CaM was degraded much faster than native CaM by a proteasome-dependent process. Similarly, in HeLa cell extracts aged CaM was degraded at a higher rate, even though it was not conjugated to ubiquitin more rapidly than the native species. Ca(2+) stimulated the ubiquitination of both species, but inhibited their degradation. Thus, for CaM, ubiquitination and proteolysis appear to be dissociated. Accordingly, purified muscle 26 S proteasomes could degrade aged CaM and native Ca(2+)-free (apo) CaM without ubiquitination. Addition of Ca(2+) dramatically reduced degradation of the native molecules but only slightly reduced the breakdown of the aged species. Thus, upon Ca(2+) binding, native CaM assumes a non-degradable conformation, which most of the age-damaged species cannot assume. Thus, flexible conformations, as may arise from age-induced damage or the absence of ligands, can promote degradation directly by the proteasome without ubiquitination.