Background The immune-signaling dyad CD40/CD40L promotes atherogenesis, and patients with unstable angina have elevated plasma levels of soluble CD40L (sCD40L) and membrane-bound CD40L. It is unknown, however, whether elevations of circulating sCD40L precede the onset of acute cardiovascular symptoms. Methods and Results In a prospective, nested case-control evaluation of healthy middle-aged women, mean concentrations of sCD40L at baseline were significantly higher among 130 participants who subsequently developed myocardial infarction, stroke, or cardiovascular death (cases), compared with 130 age- and smoking-matched women who remained free of cardiovascular disease (controls) during a 4-year follow-up (2.86 ng/mL for cases versus 2.09 ng/mL for controls; P =0.02). Women with concentrations above the 95th percentile of the control distribution (>3.71 ng/mL) had a significantly increased relative risk (RR) of developing future cardiovascular events (RR, 3.3; 95% CI, 1.2 to 8.6; P =0.01) that remained after adjustment for usual cardiovascular risk factors (multivariate RR, 2.8; 95% CI, 0.9 to 8.0; P =0.05). Conclusions High plasma concentrations of sCD40L may be associated with increased vascular risk in apparently healthy women.

Background —This study was designed to investigate whether the serum concentration of the carboxy-terminal propeptide of procollagen type I (PIP), a marker of collagen type I synthesis, is related to myocardial fibrosis in hypertensive patients. Methods and Results —The study was performed in 26 patients with essential hypertension in which ischemic cardiomyopathy was excluded after a complete medical workup. Right septal endomyocardial biopsies were performed in hypertensive patients to quantify collagen content. Collagen volume fraction (CVF) was determined on picrosirius red–stained sections with an automated image analysis system. The serum concentration of PIP was measured by specific radioimmunoassay. Compared with normotensives, both serum PIP and CVF were increased ( P <0.001) in hypertensives. A direct correlation was found between CVF and serum PIP ( r =0.471, P <0.02) in all hypertensives. Histological analysis revealed the presence of 2 subgroups of patients: 8 with severe fibrosis and 18 with nonsevere fibrosis. Serum PIP was higher ( P <0.05) in patients with severe fibrosis than in patients with nonsevere fibrosis. Using receiver operating characteristic curves, we observed that a cutoff of 127 μg/L for PIP provided 78% specificity and 75% sensitivity for predicting severe fibrosis with a relative risk of 4.80 (95% CI, 1.19 to 19.30). Conclusions —These results show a strong correlation between myocardial collagen content and the serum concentration of PIP in essential hypertension. Although preliminary, these findings suggest that the determination of PIP may be an easy and reliable method for the screening and diagnosis of severe myocardial fibrosis associated with arterial hypertension.

Background— Elevated plasma concentrations of soluble CD40 ligand (sCD40L) indicate increased risk for future cardiovascular events in apparently healthy women. This study tested the hypothesis that plasma sCD40L, alone or in combination with troponin (cTnI) or C-reactive protein (CRP), may identify patients with acute coronary syndromes at heightened risk for recurrent cardiac events. Methods and Results— In a nested case-control study (cases, n=195; controls, n=195) within the OPUS-TIMI16 trial, patients with the prespecified study end points death, myocardial infarction (MI), or congestive heart failure (CHF) within 10 months had significantly higher median (25th, 75th percentiles) sCD40L plasma levels than did controls (0.78 [0.34, 1.73] ng/mL versus 0.52 [0.16, 1.42] ng/mL, P <0.002). After adjustment for other risk predictors and levels of cTnI and CRP, sCD40L levels above median were associated with higher risk for death, MI, and the composite death/MI or death/MI/CHF (adjusted hazard ratios, 1.9 [ P <0.05], 1.9 [ P <0.001], 1.9 [ P <0.001], and 1.8 [ P <0.01], respectively). Interestingly, patients with elevated plasma levels of sCD40L and cTnI showed a markedly increased risk of death, MI, or death/MI/CHF compared with patients with the lowest levels of both markers (adjusted hazard ratios, 12.1, 7.2, and 4.3, respectively; all P <0.01). Conclusions— Elevated plasma levels of sCD40L identify patients with acute coronary syndromes at heightened risk of death and recurrent MI independent of other predictive variables, including cTnI and CRP. Notably, combined assessment of sCD40L with cTnI complements prognostic information for death and MI.

Background —This study was designed to investigate whether collagen type I degradation is altered in patients with essential hypertension and whether this alteration could be related to disturbances in the serum matrix metalloproteinase pathway of collagen degradation. A second aim of the study was to assess whether some relation exists between serum markers of collagen type I degradation and left ventricular hypertrophy in hypertensive patients. Methods and Results —We measured serum concentrations of carboxy-terminal telopeptide of collagen type I (CITP) as a marker of extracellular collagen type I degradation, of total matrix metalloproteinase-1 (MMP-1), or collagenase, of total tissue inhibitor of metalloproteinases 1 (TIMP-1), and of MMP-1/TIMP-1 complex in 37 patients with never-treated essential hypertension and in 23 normotensive control subjects. Serum concentrations of free MMP-1 and free TIMP-1 were calculated by subtracting the values of MMP-1/TIMP-1 complex from the values of total MMP-1 and total TIMP-1, respectively. Measurements were repeated in 26 hypertensive patients after 1 year of treatment with the ACE inhibitor lisinopril. Baseline free MMP-1 was decreased ( P <0.001) and baseline free TIMP-1 was increased ( P <0.001) in hypertensives compared with normotensives. No significant differences were observed in the baseline values of CITP between the 2 groups of subjects. Hypertensive patients with baseline left ventricular hypertrophy exhibited lower values of free MMP-1 ( P <0.01) and CITP ( P <0.05) and higher ( P <0.001) values of free TIMP-1 than hypertensive patients without baseline left ventricular hypertrophy. Treated patients attained an increase ( P <0.001) in free MMP-1 and a decrease ( P <0.05) in free TIMP-1. In addition, serum CITP was increased ( P <0.05) in treated hypertensives compared with normotensive subjects. Conclusions —These findings suggest that systemic extracellular degradation of collagen type I is depressed in patients with essential hypertension and can be normalized by treatment with lisinopril. A depressed degradation of collagen type I may facilitate organ fibrosis in hypertensive patients, namely, in those with left ventricular hypertrophy.

Background We investigated whether serum concentration of carboxy-terminal propeptide of procollagen type I (PIP), a marker of collagen type I synthesis, can be used to assess the ability of antihypertensive treatment to regress myocardial fibrosis in hypertensive patients. Methods and Results The study was performed in 37 patients with essential hypertension and hypertensive heart disease. After randomization, 21 patients were assigned to losartan and 16 patients to amlodipine treatment. At baseline and after 12 months, right septal endomyocardial biopsies were performed to quantify collagen volume fraction (CVF) on picrosirius red–stained sections with an automated image-analysis system. Serum PIP was measured by specific radioimmunoassay. Nineteen patients in the losartan group and 11 in the amlodipine group finished the study. Time-course changes in blood pressure during treatment were similar in the 2 groups of patients. In losartan-treated patients, CVF decreased from 5.65±2.03% to 3.96±1.46% ( P <0.01) and PIP from 127±30 to 99±26 μg/L ( P <0.01). Neither CVF or PIP changed significantly in amlodipine-treated patients. CVF was directly correlated with PIP ( r =0.44, P <0.001) in all hypertensives before and after treatment. Conclusions These findings suggest that the ability of antihypertensive treatment to regress fibrosis in hypertensives with biopsy-proven myocardial fibrosis is independent of its antihypertensive efficacy. Our data also suggest that blockade of the angiotensin II type 1 receptor is associated with inhibition of collagen type I synthesis and regression of myocardial fibrosis in hypertensives. Thus, determination of serum PIP may be useful to assess the cardioreparative properties of antihypertensive treatment in hypertensives.

Background— Considerable evidence implicates the proinflammatory cytokine CD40 ligand (CD40L) in atherosclerosis and accumulating data link type 1 and 2 diabetes, conditions associated with accelerated atherosclerosis, to inflammation. This study therefore evaluated the hypothesis that diabetic patients have elevated plasma levels of soluble CD40L (sCD40L) and that treatment with the insulin-sensitizing thiazolidinediones lowers this index of inflammation. Methods and Results— Subjects with type 1 (n=49) or type 2 diabetes (n=48) had higher ( P <0.001) sCD40L plasma levels (6.56±3.27 and 6.67±2.90 ng/mL, respectively) compared with age-matched control groups (1.40±2.21 and 1.32±2.68 ng/mL, respectively). Multiple regression analysis demonstrated a significant ( P <0.001) association between plasma sCD40L and type 1 as well as type 2 diabetes, independent of total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, blood pressure, body mass index, gender, C-reactive protein, and soluble intracellular adhesion molecule-1. Furthermore, in a pilot study, administration of troglitazone (12 weeks, 600 mg/day), but not placebo, to type 2 diabetics (n=68) significantly ( P 3 years) with or without macrovascular complications (−34% and −29%, respectively) as well as in type 2 diabetic patients with more recent (<3 years) onset of the disease (−27%; all P <0.05). Conclusions— This study provides new evidence that individuals with type 1 or 2 diabetes have a proinflammatory state as indicated by elevated levels of plasma sCD40L. Troglitazone treatment of type 2 diabetic patients diminishes sCD40L levels, suggesting a novel antiinflammatory mechanism for limiting diabetes-associated arterial disease.