Activated protein C levels and outcome in patients with cardiogenic shock complicating acute myocardial infarction.

INTRODUCTION: In patients with severe sepsis, low levels of activated protein C are associated with high morbidity and mortality. In an observational study we investigated whether patients with cardiogenic shock have decreased circulatory levels of activated protein C, and if these are associated with increased mortality. METHODS: We measured serum activated protein C and interleukin-6 levels in 43 patients with cardiogenic shock following acute myocardial infarction and in 15 control patients with uncomplicated myocardial infarction at days 0-5 and 7 after the onset of shock/myocardial infarction. RESULTS: Activated protein C levels were significantly lower in patients with cardiogenic shock compared to controls. In cardiogenic shock patients, there was no difference in activated protein C levels at baseline, whereas activated protein C levels significantly declined in 28-day non-survivors at day 2, compared with 28-day survivors. Lower levels of activated protein C were associated with a higher degree of vasopressor need, whereas there was no significant association with multiple organ failure in the first days. Regarding the inflammatory response, a strong inverse correlation was observed between interleukin-6 and activated protein C levels. CONCLUSION: Patients with cardiogenic shock who did not survive up to 28 days showed a decline in activated protein C levels during the course of the disease, which was inversely correlated with interleukin-6. This study underlines sustained inflammatory mechanisms in the development and persistence of cardiogenic shock, highlighting a potential effect of anti-inflammatory interventions early during cardiogenic shock.

An increase of VEGF plasma levels is associated with restenosis of drug-eluting stents.

AIMS: Drug-eluting stents (DES) reduce late lumen loss compared to bare metal stents but were not able to eradicate in-stent restenosis (ISR) fully. Vascular endothelial growth factor (VEGF) may inhibit late lumen loss through accelerated reendothelialisation, but may also promote neointima formation by proinflammatory effects. The aim of this study was to evaluate whether endogenous plasma levels of VEGF are associated with development of ISR after implantation of DES. METHODS AND RESULTS: We studied 85 patients who were treated with 159 DES. VEGF plasma levels were determined before and 24 hours after PCI. During the eight-month follow-up period, two patients (2.4%) died of cardiovascular causes and 12 patients (14.5% of patients, 7.6% of stents) developed angiographic ISR. Basal VEGF plasma levels were not different in patients with and without ISR at follow-up. In contrast to patients without ISR, VEGF increased significantly upon PCI in patients with ISR (p<0.005). Patients with a decrease of VEGF after PCI had a restenosis rate of 2.4% compared to a restenosis rate of 26.2% in patients with an increase of VEGF after the procedure (p<0.05). This was independent from clinical and angiographic risk factors. CONCLUSIONS: Basal plasma levels of VEGF are not associated with the development of ISR. However, an increase of VEGF after PCI is associated with a dramatically increased ISR rate after implantation of DES.

A multi-biomarker risk score improves prediction of long-term mortality in patients with advanced heart failure.

BACKGROUND: Accurate risk prediction is important for an adequate management of heart failure (HF) patients. We assessed the incremental prognostic ability of a multi-biomarker approach in advanced HF. METHODS: In 349 patients with advanced HF (median 75 years, 66% male) we investigated the incremental prognostic value of 12 novel biomarkers involved in different pathophysiological pathways including inflammation, immunological activation, oxidative stress, cell growth, remodeling, angiogenesis and apoptosis. RESULTS: During a median follow-up of 4.9 years 55.9% of patients died. Using multivariable Cox regression and bootstrap variable-selection age, chronic obstructive pulmonary disease, N-terminal pro-B-type natriuretic peptide (NT-proBNP) and the following 5 novel biomarkers were retained in the best mortality prediction model: the chemokine fractalkine, the angiogenic and mitogenic hepatocyte growth factor (HGF), the growth differentiation factor 15 (GDF-15) influencing cardiac remodeling and apoptosis, and the 2 pro-apoptotic molecules soluble apoptosis-stimulating fragment (sFAS) and soluble tumor necrosis factor-related apoptosis-inducing ligand (sTRAIL). This multi-biomarker score had strong discriminatory power for 5-year mortality (area under the Receiver Operating Characteristic curve [AUC]=0.81) and improved risk prediction beyond the prognostic power of a comprehensive conventional risk score including known clinical predictors and NT-proBNP (AUC=0.77). Net reclassification confirmed a significant improvement of individual risk prediction (p=0.003). CONCLUSIONS: Risk prediction by a multi-biomarker score is superior to a conventional risk score including clinical parameters and NT-proBNP. Additional predictive information from different biological pathways reflects the multisystemic character of HF.

The prognostic impact of soluble apoptosis-stimulating fragment on mortality in patients with carotid atherosclerosis.

BACKGROUND AND PURPOSE: Markers of apoptosis are associated with cardiovascular disease. The soluble apoptosis-stimulating fragment (sFAS) was found to be a predictor for outcome in patients with heart failure, but its importance in patients with atherosclerotic disease has not been fully understood as yet. The aim of the present study was to investigate the impact of sFAS on all-cause and cardiovascular mortality in patients with atherosclerosis in the carotid arteries. METHODS: We studied 981 of 1286 consecutive patients with neurological asymptomatic carotid atherosclerosis as evaluated by duplex Doppler sonography. Patients were prospectively followed for long-term all-cause and cardiovascular mortality. RESULTS: During a median follow-up of 6.2 years (interquartile range, 5.9 to 6.6 years), a total of 250 deaths (25.5%), including 165 (66%) cardiovascular deaths, were recorded. The risk for all-cause and for cardiovascular mortality, respectively, increased significantly with sFAS concentrations (P<0.001). The hazard ratio for all-cause death was elevated by 2.3-fold (P<0.001) and for cardiovascular death by 2.4-fold (P<0.001) in patients within the highest quintile of sFAS compared with patients within the lowest quintile, respectively. Results remained significant after adjustment for potential confounders and established cardiovascular risk factors, including high-sensitivity C-reactive protein. Patients with high sFAS but low high-sensitivity C-reactive protein had a comparable survival rate with those with elevated high-sensitivity C-reactive protein only (P=0.50). CONCLUSIONS: Markers of apoptosis, as measured by sFAS, were found to be independent risk predictors for death in patients with atherosclerotic disease in the carotid arteries.

Differences in the predictive value of tumor necrosis factor-like weak inducer of apoptosis (TWEAK) in advanced ischemic and non-ischemic heart failure.

OBJECTIVE: To assess the prognostic value of the pro-apoptotic, but also cell growth-inducing molecule soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) in heart failure (HF). METHODS: We assayed sTWEAK levels in 351 patients with advanced HF (non-ischemic: 130, ischemic: 221). During a median follow-up of 4.9 years, 195 patients (56%) died. RESULTS: sTWEAK concentrations were associated with extended survival in patients with non-ischemic (P=0.022), but not with ischemic HF (P=0.82). The inverse association in non-ischemic HF remained significant in a multivariable Cox regression model (P=0.025) with a hazard ratio of 0.40 (95% confidence interval: 0.21-0.77) comparing the third to the first tertile (P=0.007). CONCLUSION: Low sTWEAK levels independently predict mortality in advanced non-ischemic HF. sTWEAK-induced proliferation of cardiomyocytes may explain its impact on suvival. The different prognostic value of sTWEAK in ischemic and non-ischemic HF may point towards distinct pathogenic pathways determining the course of disease.

Prognostic value of pigment epithelium-derived factor in patients with advanced heart failure.

OBJECTIVE: Whereas angiogenesis, the formation of new blood vessels from preexisting vessels, may be beneficial in restoring failing myocardium, apoptosis may contribute to the progression of heart failure (HF). We investigated the role of pigment epithelium-derived factor (PEDF), a recently discovered antiangiogenic factor with additional proapoptotic effects, in patients with advanced HF. METHODS: We assayed PEDF levels in 351 patients with advanced HF at baseline. During the median follow-up time of 16 months, 50% of patients experienced the composite end point of rehospitalization and/or death. RESULTS: The risk of a clinical event increased with concentrations of the antiangiogenic marker PEDF, with a 1.94-fold higher risk in the third tertile compared with the first tertile (95% CI, 1.33-2.84). This association remained significant after adjustment for B-type natriuretic peptide (BNP) and other risk factors in a Cox regression model (P = .015). Experimental data revealed that PEDF may contribute to the progression of HF by inducing apoptosis in human cardiac myocytes and fibroblasts via activation of caspase 3. CONCLUSIONS: We suggest a role of PEDF in the progression of HF by inducing apoptosis of human cardiac myocytes and fibroblasts. Our clinical data suggest that PEDF concentrations may have the potential to become a valuable marker of the prognosis of HF, in addition to BNP.

Non-conventional markers of atherosclerosis before and after gastric banding surgery.

AIMS: Obesity and type 2 diabetes are associated with increased cardiovascular risk and elevation of traditional and non-traditional risk markers. As bariatric surgery reduces overweight and improves metabolic derangement, we examined a cluster of established and emerging cardiovascular risk factors, such as soluble CD40 ligand (sCD40L) and lipoprotein-associated phospholipase A(2) (Lp-PLA(2)), which might improve prediction of future cardiovascular events because of their more direct involvement in plaque destabilization. METHODS AND RESULTS: Obese patients [n = 32, body mass index (BMI) 46.1 +/- 5.9 kg/m(2)] underwent clinical examinations and blood sampling for measurement of glucose and lipid parameters as well as non-traditional cardiovascular risk markers, i.e. high-sensitivity C-reactive protein, plasminogen activator inhibitor-1 (PAI-1), soluble cellular adhesion molecules (CAM), MMP-2, MMP-9, CD40L, and Lp-PLA(2) before and after 1 year following laparoscopic adjustable gastric banding (LAGB), respectively. In patients undergoing LAGB, blood pressure (P < 0.0001) and blood glucose (P = 0.02) were significantly lowered by approximately 16% as well as triglyceride levels by approximately 29% (P = 0.002). In addition to a decrease of the inflammatory and pro-thrombotic marker PAI-1 (P = 0.001), CAMs, and MMP-9 (P = 0.004) were reduced, whereas no change was observed for plasma levels of MMP-2, sCD40L, and Lp-PLA(2) after LAGB, respectively. Individual changes in (ICAM-1) intercellular adhesion molecule-1 (DeltaICAM-1) were related to changes in insulin (Deltafasting insulin) before and after LAGB (r = 0.36 and r = 0.38; both P = 0.04). E-selectin correlated positively with changes in BMI (r = 0.38; P = 0.04 and r = 0.36; P = 0.05), while Lp-PLA(2) concentration was negatively correlated with BMI (r =-0.41; P = 0.02) after 1 year. Changes were comparable in both overweight diabetic and non-diabetic subjects. CONCLUSION: LAGB not only induced weight loss but also an improvement in the subclinical pro-inflammatory state. However, concentrations of most of the non-traditional risk factors for plaque instability, i.e. MMP-9, sCD40L, and Lp-PLA(2) remained unchanged.

Prognostic value of apoptosis markers in advanced heart failure patients.

AIMS: Apoptosis plays an important role in the progression of heart failure (HF). The purpose of this study was to assess whether the pro-apoptotic molecules apoptosis-stimulating fragment (FAS, CD95/APO-1) and tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) predict event-free survival of HF patients. METHODS AND RESULTS: We assayed soluble (s)FAS and sTRAIL levels in 351 patients with advanced HF. During the median follow-up time of 16 months, 175 patients (50%) experienced the composite endpoints: rehospitalization and death. The hazard increased with sFAS concentrations, with a hazard ratio of 2.3 comparing fourth and first quartiles. This association remained significant after adjustment for B-type natriuretic peptide (BNP) and other risk factors in a Cox regression model (P = 0.014). Patients with high sFAS but low BNP had a comparable event-free survival rate with those with elevated BNP only (P = 0.78). Conversely, high sTRAIL concentrations were related to a better prognosis. Particularly, the risk of mortality dropped by 70% in the fourth quartile of sTRAIL (P = 0.001, multivariable Cox regression model). CONCLUSION: sFAS is an independent risk predictor in advanced HF patients. It may be of particular value for the identification of high-risk patients in addition to BNP. Conversely, sTRAIL appears to be protective and could be an interesting therapeutic agent.

Clopidogrel pretreatment abolishes increase of PAI-1 after coronary stent implantation.

BACKGROUND: Plasminogen activator inhibitor-1 (PAI-1) has been shown to increase after percutaneous coronary intervention (PCI). Whether activated platelets, local trauma with activation of resident vascular cells or the acute phase response is the source of this PAI-1 increase is not well defined. Therefore we examined whether intensive platelet inhibition may modulate PAI-1 levels or whether the PAI-1 increase is associated with the acute phase protein C-reactive protein (CRP). METHODS: We included 51 patients with stable angina who underwent elective PCI with stent implantation. At the time of study, routine pretreatment with clopidogrel before PCI was not standard of care, but left to the discretion of the referring cardiologist. We matched 17 patients with stable angina that were not pretreated with clopidogrel but received a loading dose of 300 mg immediately after stent implantation according age, sex and smoking with 34 patients that received clopidogrel at least 12 to 24 hours before PCI. Blood samples for measurement of PAI-1, t-PA and CRP were taken directly before and 24 hours after the procedure. RESULTS: PAI-1 and t-PA active antigen plasma levels before PCI were not different in patients with and without clopidogrel pretreatment. Whereas PCI induced a significant increase of PAI-1 levels in patients without pretreatment (p<0.05), the procedure had no effect on PAI-1 active antigen in patients pretreated with clopidogrel. This resulted in significant lower PAI-1 plasma levels 24 hours after PCI in patients with pretreatment (p<0.05). CRP was not associated with pre- or postprocedural PAI-1 levels. CONCLUSION: Clopidogrel pretreatment completely abolishes the increase of PAI-1 active antigen after coronary stent implantation. This suggests that peri-procedural platelet activation might play a major role for the increase of PAI-1 after PCI thus increasing the risk of acute and subacute thrombus formation based on a reduced endogenous fibrinolytic system.

Time course of prothrombotic and proinflammatory substance release after intracoronary stent implantation.

We hypothesized that restenosis after coronary stenting is predicted by elevated levels of markers of thrombus formation and inflammation. Plasma levels of representative markers of inflammation, the thrombin and plasmin activation systems and adhesion molecules were measured in 59 patients with stable angina pectoris before, immediately after and 6 hours (h), 12 h, 24 h, one month and six months after elective stent implantation (radioactive phosphorus-32 stents/RSs/ n = 16, bare-metal stents/BMSs/ n = 43). All patients underwent clinical and angiographic follow-up (FUP) six months after stenting. RSs had significantly higher angiographic severity of restenosis than BMSs (47.1 +/- 20.1% vs. 27.6 +/- 22.0%, p = 0.003). Repeated measures ANOVA revealed significant differences between the BMS and RS groups as regards the increases in plasma levels of vascular cell adhesion molecule-1 (VCAM-1, p = 0.022), plasminogen activator inhibitor-1 (PAI-1, p = 0.047), tissue-type plasminogen activator (tPA, p = 0.047) and CD40 ligand (CD40L, p = 0.038). tPA levels tended to increase immediately after stenting in both groups, whereas the PAI-1 level one month after stenting was elevated significantly only in the RS group. In the RS group, the plasma levels of CD40L were increased at 24 h and six months after stenting, and the VCAM-1 level rose immediately after stenting and remained high during the FUP. Multivariate analysis on pooled laboratory data of both groups revealed elevated levels of VCAM-1 at 12 h and at six months as significant predictors of the severity of stent restenosis. In conclusion, the process of inflammation and thrombosis occurring after coronary interventions seems to be prolonged and enhanced in patients with high-grade restenosis at the follow up.

Plasma concentrations of interleukin-6, organ failure, vasopressor support, and successful coronary revascularization in predicting 30-day mortality of patients with cardiogenic shock complicating acute myocardial infarction.

OBJECTIVE: Inflammation may play an important role in the pathogenesis, persistence, and prognosis of cardiogenic shock. We analyzed whether elevated plasma concentrations of inflammatory markers are independently associated with an adverse prognosis (increased 30-day mortality rate) in patients with cardiogenic shock. DESIGN: Retrospective study. SETTING: Single-center study, eight-bed intensive care unit at a university hospital. PATIENTS: Retrospective study on stored plasma samples from 38 patients with cardiogenic shock complicating acute myocardial infarction. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Thirty-day nonsurvivors (n = 23, 61%) had been less frequently successfully revascularized, exhibited more frequently renal failure, needed higher vasopressor doses, and presented with significantly higher interleukin-6 plasma concentrations on intensive care unit admission than 30-day survivors. Univariate hazard ratios (95% confidence interval) for 30-day mortality were 1.49 (1.24-1.80) for every 50 pg/mL increase in the interleukin-6 plasma concentration (p = .00003), 1.06 (1.02-1.10) for every 0.1 microg x kg x min increase in the total vasopressor dose (p = .007), 1.14 (1.04-1.25) for every mmol/L increase in serum lactate (p = .006), 2.47 (1.06-5.73) for acute renal failure (p = .036), and 0.34 (0.14-0.82) for successful revascularization (p = .016). However, interleukin-6 plasma concentrations were correlated with vasopressor need and were significantly higher in patients with acute renal failure and in patients without or unsuccessful revascularization. In a multivariate Cox-proportional hazard model, interleukin-6 was the only significant predictor of 30-day mortality with a hazard ratio of 1.42 (1.12-1.80, p = .004). Accordingly, interleukin-6 concentrations > or =200 pg/mL (the point of maximum interest by receiver operating characteristic analysis with a specificity of 87% and a sensitivity of 74%) were associated with a significantly increased 30-day mortality rate in both patients with and patients without successful revascularization. CONCLUSIONS: Interleukin-6 concentrations are an independent predictor of 30-day mortality in patients with acute myocardial infarction complicated by cardiogenic shock.

Prostaglandin E1 induces vascular endothelial growth factor-1 in human adult cardiac myocytes but not in human adult cardiac fibroblasts via a cAMP-dependent mechanism.

Prostaglandin E(1) (PGE(1)) has been used to treat pulmonary hypertension and peripheral artery occlusive disease and has been successfully employed for pharmacological bridging to transplantation in patients with chronic end-stage heart failure. In addition to its vasoactive effects PGE(1) was shown to stimulate angiogenesis in animal models. Recently we showed that PGE(1)-induced angiogenesis in hearts of patients with ischemic heart disease. We proposed that the angiogenic action of PGE(1) is mediated by vascular endothelial growth factor (VEGF). In the present paper we studied a possible effect of PGE(1) on the expression of VEGF-1 in cultured human adult cardiac myocytes (HACM) and cultured human adult cardiac fibroblasts (HACFB), respectively, to identify a cellular source of VEGF-1 in patients treated with PGE(1). We also aimed to delineate mechanisms involved in a possible regulation of VEGF-1 by PGE(1) in these cells. When HACM, isolated from human myocardial tissue, were treated with PGE(1), a significant up to 3-fold increase in VEGF-1 production could be observed. These results could be confirmed on the level of specific mRNA expression as determined by real-time polymerase chain reaction. The effect of PGE(1) on VEGF-1 expression could be blocked by H089, an inhibitor of cAMP-dependent protein kinase A. In HACFB, also isolated from human myocardial tissue, no effect of PGE(1) on VEGF-1 production was seen. If this effect of PGE(1) is also operative in the in vivo situation, one could speculate that cardiac myocytes could be a cellular source of PGE(1)-induced VEGF-1 expression in patients treated with this drug.

Polymorphic membrane protein (PMP) 20 and PMP 21 of Chlamydia pneumoniae induce proinflammatory mediators in human endothelial cells in vitro by activation of the nuclear factor-kappaB pathway.

We tested whether polymorphic membrane proteins (PMPs) of Chlamydia pneumoniae might play a role in triggering an inflammatory response in human endothelial cells. Of 15 purified, recombinant chlamydial PMPs tested, 2 (PMP 20 and PMP 21) dose-dependently increased the production of the inflammatory mediators interleukin (IL)-6 and monocyte chemoattractant protein-1 (MCP-1), in cultured human endothelial cells; production of IL-8 was also increased. When endothelial cells were infected by live C. pneumoniae, an increase in the production of IL-6, IL-8, and MCP-1 was seen. We used adenovirus-induced overexpression of IkappaBalpha-an inhibitor of nuclear factor (NF)-kappaB-to demonstrate that PMP 20 and PMP 21 increase the production of IL-6 and MCP-1 in human endothelial cells by activation of the NF-kappaB pathway, because, in cells overexpressing IkappaBalpha, treatment with the respective PMP did not result in increased production of IL-6 and MCP-1. Thus, C. pneumoniae could, by interactions of its PMPs with the endothelium, contribute to the process of vascular injury during the development and progression of atherosclerotic lesions.

Plasminogen activator inhibitor 1 expression is regulated by the inflammatory mediators interleukin-1alpha, tumor necrosis factor-alpha, transforming growth factor-beta and oncostatin M in human cardiac myocytes.

Accumulating evidence points towards a role for proteases and protease inhibitors in tissue remodelling and repair in a variety of organs. In particular-besides the matrix metalloprotease system-the plasminogen activator (PA)/plasmin system has been implicated in these processes in the heart. Urokinase type PA (u-PA) and PA inhibitor type 1 (PAI-1) seem to modulate cardiac rupture and infarct healing. In this study we aimed to investigate whether inflammatory mediators can regulate the expression of components of the PA/plasmin system in human adult cardiac myocytes (HACM). We could demonstrate that HACM, isolated from pieces of myocardial tissue by mechanical dispersion and characterized by positive immunostaining for the cardiac markers troponin I, tropomyosin, cardiotin and myocardial muscle-actin, in vitro express PAI-1 and tissue type PA (t-PA) whereas u-PA was not detectable in these cells. PAI-1 protein production was increased up to twofold by interleukin-1alpha (IL-1alpha) and tumor necrosis factor-alpha (TNF-alpha) and up to fivefold by transforming growth factor-beta (TGF-beta) and oncostatin M (OSM). Similar changes were observed in PAI-1 transcript levels after cytokine treatment. t-PA production in HACM was not affected by these agonists. No effect of these cytokines on PAI-1 production in fibroblasts isolated from human myocardial tissue was seen. In an ex vivo model we could show that incubation of pieces of human myocardial tissue with these cytokines also resulted in an increase in PAI-1 in cardiac myocytes as evidenced by immuno-histochemistry. Furthermore we found increased PAI-1 expression in myocardial tissue from a patient suffering from acute myocarditis. Thus for the first time we provide evidence that inflammatory mediators modulate PAI-1 expression in human adult cardiac myocytes in vitro and ex vivo and could demonstrate that PAI-1 expression is increased in the in vivo setting under inflammatory conditions. If the effect on PAI-1 expression brought about by IL-1alpha, TNF-alpha, TGF-beta and OSM is not only operative under in vitro and ex vivo conditions but also in the in vivo setting one could speculate that these cytokines contribute to upregulation of PAI-1 in myocardial tissue and that PAI-1, when upregulated in myocardial tissue during inflammatory processes, could serve as a defence mechanism against excessive matrix degradation by proteases. Thus we propose a role for PAI-1 produced in the heart by cardiac myocytes in cardiac remodelling and repair processes.

Multiple organ failure in patients with cardiogenic shock is associated with high plasma levels of interleukin-6.

OBJECTIVE: In patients with septic shock, multiple organ failure (MOF) is associated with high levels of interleukin-6 (IL-6). Although organ failure is also a common complication of cardiogenic shock (CS), IL-6 levels have been reported to be lower in patients with CS than in patients with septic shock. We studied IL-6 plasma levels in patients with CS with respect to organ failure. SETTING: Eight-bed intensive care unit at a university hospital. PATIENTS: Fifty-one patients with CS, 26 patients with septic shock, and 11 noncritically ill controls. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients with CS had higher IL-6 levels than noncritically ill controls ( p<.001) but lower levels than patients with septic shock ( p=.003). CS patients with MOF at the time of blood sampling exhibited, however, higher IL-6 levels than CS patients without organ failure, and IL-6 levels in patients with CS correlated to the total Sepsis-related Organ Failure Assessment score at the time of blood sampling ( r=.57, <.001). No significant differences in IL-6 levels were found when comparing CS patients with MOF at the time of blood sampling with patients with septic shock. Furthermore, CS patients who developed MOF during ICU stay exhibited significantly higher IL-6 levels than CS patients who never did develop MOF. An IL-6 level of >200 pg/mL had a 93% specificity and 100% sensitivity for the prediction of MOF in patients with CS. CONCLUSIONS: Once MOF is present, patients with CS exhibit similarly high IL-6 levels as patients with septic shock. High IL-6 levels in CS patients are associated with a progression to MOF.

HMG CoA reductase inhibitors affect the fibrinolytic system of human vascular cells in vitro: a comparative study using different statins.

1. The results of several clinical studies investigating the effect of statin therapy on the fibrinolytic system in vivo are inconclusive. We compared the effect of six different statins (atorvastatin, cerivastatin, fluvastatin, lovastatin, pravastatin, simvastatin) on components of the fibrinolytic system expressed by human vascular endothelial cells and smooth muscle cells and by the human hepatoma cell line HepG2. 2. All statins used except pravastatin significantly decreased PAI-1 production in human endothelial and smooth muscle cells. This effect was also seen in the presence of IL-1 alpha and TNF-alpha. All statins except pravastatin increased t-PA production in human smooth muscle cells. On a molar basis cerivastatin was the most effective HMG CoA reductase inhibitor used. Only simvastatin and lovastatin increased t-PA production in endothelial cells. The effects on the fibrinolytic system were reversed by mevalonate. Statins decreased mRNA levels for PAI-1 in endothelial and smooth muscle cells and increased mRNA levels for t-PA in smooth muscle cells. Statins did not affect PAI-1 expression in HepG2 cells. Cell viability was not influenced by statins in endothelial cells and HepG2 cells whereas in smooth muscle cells a cytotoxic effect was seen at high concentrations. 3. If the effects on the fibrinolytic system of vascular cells in vitro shown in this study are also operative in vivo one could speculate that by increasing t-PA and decreasing PAI-1 at sites of vascular lesions statins might reduce fibrin formation and thrombus development. Such an effect might contribute to the clinically proven benefits of statin therapy.