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(1) Background: The aim of the study was to assess the risk of heart failure (HF) in elderly treated hypertensive patients with white coat uncontrolled hypertension (WUCH), ambulatory nonresistant hypertension (ANRH) and ambulatory resistant hypertension (ARH), when compared to those with controlled hypertension (CH). (2) We studied 745 treated hypertensive subjects older than 65 years. CH was defined as clinic blood pressure (BP) < 140/90 mmHg and 24-h BP < 130/80 mmHg; WUCH was defined as clinic BP ≥ 140/90 mmHg and 24-h BP < 130/80 mmHg; ANRH was defined as 24-h BP ≥ 130/80 mmHg in patients receiving ≤2 antihypertensive drugs; ARH was defined as 24-h BP ≥ 130/80 mmHg in patients receiving ≥3 antihypertensive drugs. (3) Results: 153 patients had CH, 153 had WUCH, 307 had ANRH and 132 (18%) had ARH. During the follow-up (8.4 ± 4.8 years), 82 HF events occurred. After adjustment for various covariates, when compared to CH, the hazard ratio (95% confidence interval) for HF was 1.30 (0.51–3.32), 2.14 (1.03–4.43) and 3.52 (1.56–7.96) in WUCH, ANRH and ARH, respectively. (4) Conclusions: among elderly treated hypertensive patients, those with ARH are at a considerably higher risk of developing HF when compared to CH. [ABSTRACT FROM AUTHOR]

(1) Background: The aim of this study was to assess the prognostic impact of 24-hour pulse pressure (PP), elastic PP (elPP) and stiffening PP (stPP) in elderly treated hypertensive patients; (2) Methods: In this retrospective study, we evaluated 745 treated hypertensive subjects older than 65 years who underwent ambulatory blood pressure monitoring to assess 24-hour PP and 24-hour elPP and stPP, as calculated by a mathematical model. The association of these PP components with a combined endpoint of cardiovascular events was investigated; (3) Results: The 24-hour PP, elPP and stPP were 59 ± 12.5, 47.5 ± 9.5 and 11.5 ± 6.5 mmHg, respectively. During the follow-up (mean 8.4 years), 284 events occurred, including coronary events, stroke, heart failure hospitalization and peripheral revascularization. In the univariate Cox regression analysis, 24-hour PP, elPP and stPP were associated with the combined outcome. After the adjustment for covariates, per one standard deviation increase, 24-hour PP had a borderline association with risk (hazard ratio (HR) 1.16, 95% confidence interval (CI) 1.00–1.34), 24-hour elPP remained associated with cardiovascular events (HR 1.20, 95% CI 1.05–1.36) and 24-hour stPP lost its significance. (4) Conclusions: 24-hour elPP is a predictor of cardiovascular events in elderly treated hypertensive patients. [ABSTRACT FROM AUTHOR]

The aim of this study was to provide prediction models for masked uncontrolled hypertension (MUCH) detected by ambulatory blood pressure (BP) monitoring in an Italian population. We studied 738 treated hypertensive patients with normal clinic BPs classified as having controlled hypertension (CH) or MUCH if their daytime BP was < or ≥135/85 mmHg regardless of nighttime BP, respectively, or CH or MUCH if their 24-h BP was < or ≥130/80 mmHg regardless of daytime or nighttime BP, respectively. We detected 215 (29%) and 275 (37%) patients with MUCH using daytime and 24-h BP thresholds, respectively. Multivariate logistic regression analysis showed that males, those with a smoking habit, left ventricular hypertrophy (LVH), and a clinic systolic BP between 130–139 mmHg and/or clinic diastolic BP between 85–89 mmHg were associated with MUCH. The area under the receiver operating characteristic curve showed good accuracy at 0.78 (95% CI 0.75–0.81, p < 0.0001) and 0.77 (95% CI 0.73–0.80, p < 0.0001) for MUCH defined by daytime and 24 h BP, respectively. Internal validation suggested a good predictive performance of the models. Males, those with a smoking habit, LVH, and high-normal clinic BP are indicators of MUCH and models including these factors provide good diagnostic accuracy in identifying this ambulatory BP phenotype. [ABSTRACT FROM AUTHOR]

Myocardial Infraction and a therothrombotic ishemic stroke are considered to be caused by the rupture of vulnerable atherosclerotic plaques, which are complex disorders that result from multifaceted interactions between an individual's genetic makeup and environmental factors.

Masked uncontrolled hypertension (MUCH) is at higher cardiovascular risk than controlled hypertension (CH). In previous studies, patients with MUCH were considered as a unique group though those receiving ≤2 drugs could be defined as having nonresistant MUCH (NRMUCH) and those receiving ≥3 drugs as having resistant MUCH (RMUCH). The aim of this study was to assess the prognostic value of NRMUCH and RMUCH detected by ambulatory blood pressure (BP) monitoring. Cardiovascular risk was evaluated in 738 treated hypertensive patients with normal clinic BP. Patients were classified as having CH or MUCH if daytime BP < or ≥ 135/85 mmHg, respectively, regardless of nighttime BP, or CH or MUCH if 24‐h BP < or ≥ 130/80 mmHg, respectively, regardless of daytime or nighttime BP. By daytime or 24‐h BP, the authors detected 523 (71%), 178 (24%), and 37 (5%) or 463 (63%), 231 (31%), and 44 (6%) patients with CH, NRMUCH, and RMUCH, respectively. During the follow‐up (median 10 years), 148 events occurred. After adjustment for covariates, compared to CH, the hazard ratio (HR), 95% confidence interval (CI), for cardiovascular events was 1.81, 1.27–2.57, and 2.99, 1.73–5.16, in NRMUCH and RMUCH defined by daytime BP, respectively, and 1.58, 1.12–2.23, and 2.21, 1.27–3.82, in NRMUCH and RMUCH defined by 24‐h BP, respectively. If RMUCH was compared with NRMUCH, the risk tended to be higher in RMUCH but did not attain statistical significance (P =.08 and P =.23 by daytime and 24‐h BP thresholds, respectively). In conclusion, both NRMUCH and RMUCH are at increased cardiovascular risk than CH. [ABSTRACT FROM AUTHOR]

The aim of this study was to perform a meta-analysis of studies evaluating the association of clinic and daytime, nighttime, and 24-h blood pressure with the occurrence of new-onset atrial fibrillation. We conducted a literature search through PubMed, Web of science, and Cochrane Library for articles evaluating the occurrence of new-onset atrial fibrillation in relation to the above-mentioned blood pressure parameters and reporting adjusted hazard ratio and 95% confidence interval. We identified five studies. The pooled population consisted of 7224 patients who experienced 444 cases of atrial fibrillation. The overall adjusted hazard ratio (95% confidence interval) was 1.05 (0.98-1.13), 1.19 (1.11-1.27), 1.18 (1.11-1.26), and 1.23 (1.14-1.32), per 10-mmHg increment in clinic, daytime, nighttime, and 24-h systolic blood pressure, respectively. The degree of heterogeneity of the hazard ratio estimates across the studies (Q and I-squared statistics) were minimal. The results of this meta-analysis strongly suggest that ambulatory systolic blood pressure prospectively predicts incident atrial fibrillation better than does clinic systolic blood pressure and that daytime, nighttime, and 24-h systolic blood pressure are similarly associated with future atrial fibrillation. [ABSTRACT FROM AUTHOR]

BACKGROUND Masked uncontrolled hypertension (MUCH), that is, nonhypertensive clinic but high out-of-office blood pressure (BP) in treated patients is at increased cardiovascular risk than controlled hypertension (CH), that is, nonhypertensive clinic and out-of-office BP. Using ambulatory BP, MUCH can be defined as daytime and/or nighttime and/or 24-hour BP above thresholds. It is unclear whether different definitions of MUCH have similar prognostic information. This study assessed the prognostic value of MUCH defined by different ambulatory BP criteria. METHODS Cardiovascular events were evaluated in 738 treated hypertensive patients with nonhypertensive clinic BP. Among them, participants were classified as having CH or daytime MUCH (BP ≥135/85 mm Hg) regardless of nighttime BP (group 1), nighttime MUCH (BP ≥120/70 mm Hg) regardless of daytime BP (group 2), 24-hour MUCH (BP ≥130/80 mm Hg) regardless of daytime or nighttime BP (group 3), daytime MUCH only (group 4), nighttime MUCH only (group 5), and daytime + nighttime MUCH (group 6). RESULTS We detected 215 (29%), 357 (48.5%), 275 (37%), 42 (5.5%),184 (25%) and 173 (23.5%) patients with MUCH from group 1 to 6, respectively. During the follow-up (10 ± 5 years), 148 events occurred in patients with CH and MUCH. After adjustment for covariates, compared with patients with CH, the adjusted hazard ratio (95% confidence interval) for cardiovascular events was 2.01 (1.45–2.79), 1.53 (1.09–2.15), 1.69 (1.22–2.34), 1.52 (0.80–2.91), 1.15 (0.74–1.80), and 2.29 (1.53–3.42) from group 1 to 6, respectively. CONCLUSIONS The prognostic impact of MUCH defined according to various ambulatory BP definitions may be different. [ABSTRACT FROM AUTHOR]

Myocardial Infraction and a therothrombotic ishemic stroke are considered to be caused by the rupture of vulnerable atherosclerotic plaques, which are complex disorders that result from multifaceted interactions between an individual's genetic makeup and environmental factors.

We investigated the prognostic value of morning surge (MS) of blood pressure (BP) in middle-aged treated hypertensive patients. The occurrence of a composite end point (coronary events, stroke, and heart failure requiring hospitalization) was evaluated in 1073 middle-aged treated hypertensive patients (mean age 49 years). Patients with preawakening MS of BP above the 90th percentile (27/20.5 mm Hg for systolic/diastolic BP) were defined as having high MS of BP. During the follow-up (mean 10.9 years), 131 cardiovascular events occurred. After adjustment for various covariates, including known risk markers and ambulatory BP parameters, patients with high MS of systolic BP (hazard ratio 1.81, 95% confidence interval 1.10-2.96) and those with high MS of diastolic BP (hazard ratio 1.98, 95% confidence interval 1.19-3.28) were at higher cardiovascular risk than those with normal MS. In middle-aged treated hypertensive patients, high MS of systolic and diastolic BP is independently associated with increased cardiovascular risk. [ABSTRACT FROM AUTHOR]

BackgroundCardiac outcome in patients with atherosclerotic renal artery stenosis (ARAS) undergoing percutaneous transluminal renal angioplasty (PTRA) or medical therapy is not yet completely clear. The aim of this study was to perform a meta-analysis of randomized controlled trials to compare the effect of PTRA and medical therapy on nonfatal myocardial infarction in patients with ARAS.MethodsWe searched for articles reporting cardiovascular outcome, including nonfatal myocardial infarction, in patients with renal artery stenosis randomized to PTRA with/without stenting or medical therapy.ResultsFive studies were identified. The pooled population consisted of 1,159 subjects who experienced 56 nonfatal myocardial infarctions. When compared with medical therapy, the overall relative risk (RR) was 0.85 (95% confidence interval (CI) 0.51-1.42), P = 0.55, for PTRA. There was no significant difference between PTRA and medical therapy according to procedural characteristics (with/without stent placement), mean serum creatinine at follow-up (higher or lower than 2.0 mg/dl), and maximum follow-up length (> or <2 years).ConclusionsIn patients with ARAS and hypertension, there is a lack of evidence supporting the superiority of PTRA over medical therapy in prevention of nonfatal myocardial infarction. Awaiting for results of ongoing trials, our data and previous data suggest that PTRA and drug therapy have a similar impact on cardiovascular risk reduction in patients with renal artery stenosis and hypertension.American Journal of Hypertension 2012; doi:10.1038/ajh.2012.110 [ABSTRACT FROM AUTHOR]

We have here investigated possible occurrence of bicarbonate-dependent, carbonate radical anion (CO3•−)-driven tocopherol-mediated human LDL peroxidation (TMP) in vitro and in vivo. CO3•−, generated in vitro by the SOD1/H2O2/bicarbonate system, readily promoted TMP, which was dependent on α-tocopherol and bicarbonate concentrations, and was inhibited by the CO3•− scavenger ethanol; moreover, TMP induced in vitro by the SOD1/H2O2/bicarbonate system occurred in the presence of α-tocopherol that typically underwent slow oxidative consumption. In the in vivo clinical setting, we showed that, compared to controls, hypertensive patients with diuretic-induced metabolic alkalosis and heightened blood bicarbonate concentration had lipid hydroperoxide burden and decreased α-tocopherol content in the LDL fraction, with direct significant correlation between the LDL levels of α-tocopherol and those of lipid hydroperoxides; remarkably, after resolution of metabolic alkalosis, together with normalization of blood bicarbonate concentration, the LDL content of lipid hydroperoxides was decreased and that of α-tocopherol augmented significantly. These findings suggest bicarbonate-dependent, CO3•−-driven LDL TMP in vivo. In conclusion, the present study highlights the occurrence of bicarbonate-dependent, CO3•−-driven human LDL TMP, the role of which in pathological conditions such as atherosclerosis warrants, however, further investigation. [ABSTRACT FROM AUTHOR]

Increased oxidative stress appears to be of fundamental importance in the pathogenesis and development of several disease processes. Indeed, it is well known that reactive oxygen species (ROS) exert critical regulatory functions within the vascular wall, and it is, therefore, plausible that platelets represent a relevant target for their action. Platelet activation cascade (including receptor-mediated tethering to the endothelium, rolling, firm adhesion, aggregation, and thrombus formation) is tightly regulated. In addition to already well-defined platelet regulatory factors, ROS may participate in the regulation of platelet activation. It is already established that enhanced ROS release from the vascular wall can indirectly affect platelet activity by scavenging nitric oxide (NO), thereby decreasing the antiplatelet properties of endothelium. On the other hand, recent data suggest that platelets themselves generate ROS, which may evoke pro-thrombotic responses, triggering many biological processes participating in atherosclerosis initiation, progression, and complication. That oxidative stress may alter platelet function is conceivable when considering that antioxidants play a role in the prevention of cardiovascular disease, although the precise mechanism accounting for changes attributable to antioxidants in atherosclerosis remains unknown. It is possible that the effects of antioxidants may be a consequence of their enhancing or promoting the antiplatelet effects of NO derived from both endothelial cells and platelets. This review focuses on current knowledge regarding ROS-dependent regulation of platelet function in health and disease, and summarizes in vitro and in vivo evidence for their physiological and potential therapeutic relevance.

Platelets critically contribute to atherothrombosis and worsening ischaemia in patients with peripheral arterial disease (PAD), eventually leading to critical limb ischaemia (CLI). Furthermore, persistent platelet activation despite antiplatelet therapy has been reported in this setting. The prostacyclin analogue iloprost is currently recommended in CLI patients for its effects in relieving symptoms by promoting local perfusion. In this study, we investigated the effects of iloprost infusion on urinary 11-dehydro-TXB₂ and 8-iso-PGF(₂α) excretion rate, as in vivo indexes of thromboxane-dependent platelet activation and lipid peroxidation, respectively, and on platelet-derived proinflammatory sCD40L and nitric oxide bioavailability in 44 patients with CLI while on chronic treatment with low-dose aspirin. Daily iloprost infusion for one-week significantly decreased urinary 11-dehydro-TXB₂ [499 (277-807) vs. 380 (189-560) pg/mg creatinine, p < 0.0001] and 8-iso-PGF(₂α) [533 (316-842) vs. 334 (196-540) pg/mg creatinine, p < 0.0001] as well as plasma sCD40L [1540 (1005-3015) vs. 948 (845-2030) pg/ml, p < 0.0001]. Furthermore, a significant increase in plasma nitrate plus nitrite levels has been observed [26.8 (18.8-35.9) vs. 43.7 (33.0-75.5) μM, p < 0.0001]. A significant direct correlation was also found between urinary 8-iso-PGF(₂α) and 11-dehydro-TXB2 before and after iloprost treatment (Rho = 0.695, p < 0.0001). In conclusion, we report that a short-term course of iloprost is able to significantly reduce residual thromboxane biosynthesis, oxidative stress, endothelial dysfunction and platelet-derived inflammation in low-dose aspirin treated patients with CLI.

Objective: Receptor for advanced glycation end products (AGEs) (RAGE) plays a central role in the process of plaque rupture in diabetic patients. Recently, it has been reported that RAGE may be downregulated by improving glycemic control. In contrast, despite being well known that RAGE may be induced in human vessels in a glucose-independent fashion, also by myeloperoxidase (MPO)-dependent AGE generation, no data exist regarding the possibility of a pharmacological modulation of glucose-independent RAGE generation. Thus, the aim of this study was to characterize the effect of simvastatin on the expression of RAGE and RAGE-dependent plaque-destabilizing genes in human atherosclerotic plaques., Methods and Results: Seventy type 2 diabetic patients with asymptomatic carotid artery stenosis (>70%) were randomized to American Heart Association (AHA) step 1 diet plus simvastatin (40 mg/d) or AHA step 1 diet alone for 4 months before endarterectomy. Plaque expression of MPO, AGEs, RAGE, NF-kappaB, COX-2, mPGES-1, matrix metalloproteinase (MMP)-2 and MMP-9, lipid and oxidized LDL (oxLDL) content, procollagen 1, and interstitial collagen was analyzed by immunohistochemistry and Western blot; zymography was used to detect MMP activity. Plaques from the simvastatin group had less (P<0.0001) immunoreactivity for MPO, AGEs, RAGE, p65, COX-2, mPGES-1, MMP-2, and MMP-9, lipids and oxLDL; reduced (P<0.0001) gelatinolytic activity; increased (P<0.0001) procollagen 1 and collagen content; and fewer (P<0.0001) macrophages, T-lymphocytes, and HLA-DR+ cells. Of interest, RAGE inhibition by simvastatin, observed not only in plaque sections but also in plaque-derived macrophages, was reverted by addition of AGEs in vitro., Conclusions: This study supports the hypothesis that simvastatin inhibits plaque RAGE expression by decreasing MPO-dependent AGE generation. This effect in turn might contribute to plaque stabilization by inhibiting the biosynthesis of PGE2-dependent MMPs, responsible for plaque rupture.

Objective: We recently demonstrated that inducible cyclooxygenase/PGE synthase-1 (COX-2/mPGES-1) are overexpressed in symptomatic plaques in association with PGE2-dependent metalloproteinase (matrix metalloproteinase [MMP]) biosynthesis and plaque rupture. However, it is not known which of the 4 PGE2 receptors (EP1-4) mediates macrophage metalloproteinase generation. The aim of this study was to characterize EP1-4 expression in plaques from symptomatic and asymptomatic patients undergoing carotid endarterectomy and correlate it with the extent of inflammatory infiltration, COX-2/mPGES-1 and MMP expression and clinical features of patients' presentation., Methods and Results: Plaques were analyzed for COX-2, mPGES-1, EP1-4, MMP-2, and MMP-9 by immunohistochemistry, reverse-transcription polymerase chain reaction and Western blot; zymography was used to detect MMP activity. We observed strong EP4 immunoreactivity, only very weak staining for EP2, and no expression of EP1 and EP3 in atherosclerotic plaques. EP4 was more abundant in MMP-rich symptomatic lesions, whereas EP2 was no different between symptomatic and asymptomatic plaques. Finally, MMP induction by PGE2 in vitro was inhibited by the EP4 antagonist L-161 982, but not by its inactive analog L-161 983 or by the EP2 antagonist AH6809., Conclusions: This study shows that EP4 overexpression is associated with enhanced inflammatory reaction in atherosclerotic plaques. This effect might contribute to plaque destabilization by inducing culprit metalloproteinase expression.

Objective: The participation of 5-lipoxygenase (5-LO) in the development of atherosclerosis has been suggested by recent studies. However, a role for 5-LO as a modulator of atherosclerotic plaque instability has not been previously reported in humans. Thus, the aims of this study was to analyze the expression of 5-LO in human carotid plaques and to investigate the mechanism by which this enzyme could lead to plaque instability and rupture., Methods and Results: We obtained atherosclerotic plaques from 60 patients undergoing carotid endarterectomy. We divided the plaques into symptomatic and symptomatic according to clinical evidence of plaque instability. Clinical evidence of plaque instability was provided by the assessment of recent ischemic symptoms attributable to the stenosis and by the presence of ipsilateral cerebral lesion(s) determined by computed tomography. Plaques were analyzed for CD68+ macrophages, CD3+ T cells, alpha-actin+ smooth muscle cells, 5-LO, cyclooxygenase 2, matrix metalloproteinase (MMP)-2, and MMP-9 by immunohistochemical, immunoblotting, and densitometric analyses. MMP activity was assessed by zymography. Leukotriene (LT) B4 and collagen were quantified by ELISA and Sirius red polarization, respectively. The percentage of macrophage-rich and T-cell-rich areas was larger in symptomatic compared with asymptomatic patients (25+/-6% versus 8+/-4%, P<0.0001, and 74+/-17 versus 18+/-4 cell/mm2, P<0.003). 5-LO expression was higher in symptomatic compared with asymptomatic plaques (24+/-4% versus 6+/-3%, P<0.0001) and was associated with increased MMP-2 and MMP-9 expression (27+/-4% versus 7+/-3%, P<0.0001, and 29+/-5% versus 8+/-2%, P<0.0001) and activity and with decreased collagen content (6.9+/-2.4% versus 17.8+/-3.1%, P<0.01). Immunofluorescence showed that 5-LO and MMPs colocalize in activated macrophages. Notably, higher 5-LO in symptomatic plaques correlated with increased LTB4 production (18.15+/-3.56 versus 11.27+/-3.04 ng/g tissue, P<0.0001)., Conclusions: The expression of 5-LO is elevated in symptomatic compared with asymptomatic plaques and is associated with acute ischemic syndromes, possibly through the generation of LTB4, subsequent MMP biosynthesis, and plaque rupture.

Objective: Inducible cyclooxygenase (COX-2) catalyzes the first step in prostanoid biosynthesis and is considered a proinflammatory enzyme. COX-2 and type 1 inducible PGE synthase (mPGES-1) have a role in metalloproteinase (MMP) release leading to plaque rupture. In contrast, lipocalin-type PGD synthase (L-PGDS) has been shown to exert antiinflammatory actions. Thus, in this study we investigated whether a shift from a PGDS-oriented to a PGES-oriented profile in arachidonate metabolism leads to inflammatory activation in rupture-prone plaque macrophages., Methods and Results: Atherosclerotic plaques were obtained from 60 patients who underwent carotid endarterectomy, symptomatic (n=30) and asymptomatic (n=30) according to evidence of recent transient ischemic attack or stroke. Plaques were analyzed for COX-2, mPGES-1, L-PGDS, PPARgamma, IkappaBalpha, NF-kappaB, and MMP-9 by immunocytochemistry, Western blot, reverse-transcriptase polymerase chain reaction, enzyme immunoassay, and zymography. Prostaglandin E2 (PGE2) pathway was significantly prevalent in symptomatic plaques, whereas PGD2 pathway was overexpressed in asymptomatic ones, associated with NF-kappaB inactivation and MMP-9 suppression. In vitro COX-2 inhibition in monocytes was associated with reduced MMP-9 release only when PGD2 pathway overcame PGE2 pathway., Conclusions: These results suggest that COX-2 may have proinflammatory and antiinflammatory properties as a function of expression of downstream PGH2 isomerases, and that the switch from L-PGDS to mPGES-1 in plaque macrophages is associated with cerebral ischemic syndromes, possibly through MMP-induced plaque rupture.

Background: Clinical trials have demonstrated that agents that inhibit the angiotensin II pathway confer benefit beyond the reduction of blood pressure alone. However, the molecular mechanism underlying this effect has yet to be investigated. Recently, we have demonstrated enhanced expression of inducible cyclooxygenase (COX) and prostaglandin (PG)E2-dependent synthase (COX-2/mPGES-1) in human symptomatic plaques and provided evidence that it is associated with metalloproteinase (MMP)-induced plaque rupture. Thus, the aim of this study was to characterize the effect of the angiotensin II type 1 (AT1) receptor antagonist irbesartan on the inflammatory infiltration and expression of COX-2/mPGES-1 and MMPs in human carotid plaques., Methods and Results: Seventy patients with symptomatic carotid artery stenosis were randomized to irbesartan (300 mg/d) or chlorthalidone (50 mg/d) for 4 months before endarterectomy. Plaques were subjected to analysis of COX-1, COX-2, mPGES-1, MMP-2, and MMP-9, angiotensin II, AT(1), AT2, and collagen content by immunocytochemistry, Western blot, and reverse-transcriptase polymerase chain reaction, whereas zymography was used to detect MMP activity. Immunohistochemistry was also used to identify CD68+ macrophages, CD3+ T lymphocytes, smooth muscle cells (SMCs), and HLA-DR+ inflammatory cells. Plaques from the irbesartan group had fewer (P<0.0001) macrophages, T lymphocytes, and HLA-DR+ cells; less (P<0.0001) immunoreactivity for COX-2/mPGES-1 and MMPs; reduced (P<0.0001) gelatinolytic activity; and increased (P<0.0001) collagen content. It is worth noting that COX-2/mPGES-1 inhibition was observed after incubation in vitro with irbesartan but not with the selective AT2 blockade PD123,319., Conclusions: This study demonstrates that irbesartan decreases inflammation and inhibits COX-2/mPGES-1 expression in plaque macrophages, and this effect may in turn contribute to plaque stabilization by inhibition of MMP-induced plaque rupture.

Background: Inflammation plays a pathogenic role in the development of restenosis after percutaneous transluminal coronary angioplasty (PTCA). CD40-CD40L interaction is involved in the pathogenesis of atherosclerosis; however, its role in the pathophysiology of restenosis is still unclear. We tested the hypothesis that soluble CD40L (sCD40L) may be involved in the process of restenosis and that it exerts its effect by triggering a complex group of inflammatory reactions on endothelial and mononuclear cells., Methods and Results: We studied 70 patients who underwent PTCA and who had repeated angiograms at 6-month follow-up. Plasma sCD40L was measured before and 1, 5, 15, and 180 days after PTCA, whereas plasma soluble intercellular adhesion molecule-1, soluble vascular cell adhesion molecule-1, E-selectin, and monocyte chemoattractant protein (MCP)-1 were measured before and 24 hours after PTCA. Furthermore, the release of adhesion molecules and MCP-1 and the ability to repair an injury in endothelial cells, as well as the generation of O2- in monocytes, were analyzed in vitro after stimulation with serum from patients or healthy control subjects. Restenosis occurred in 18 patients (26%). Restenotic patients had preprocedural sCD40L significantly higher than patients with favorable outcomes (2.13+/-0.3 versus 0.87+/-0.12 ng/mL, P<0.0001). Elevated sCD40L at baseline was significantly correlated with adhesion molecules and MCP-1 generation after PTCA and with lumen loss at 6-month follow-up. Furthermore, high sCD40L was directly associated in vitro with adhesion molecules and MCP-1 generation and impaired migration in endothelial cells and with enhanced O2- generation in monocytes., Conclusions: We conclude that increased sCD40L is associated with late restenosis after PTCA. This may provide an important biochemical link between restenosis and aspirin-insensitive platelet activation. These results provide a rationale for studies with new antiplatelet treatments in patients who underwent PTCA.