Plasma D-dimer as a predictor of intraluminal thrombus burden and progression of abdominal aortic aneurysm.

AIM: Intraluminal thrombus (ILT) is presented in most abdominal aortic aneurysms (AAAs) and is suggested to promote AAA expansion. D-dimer, a breakdown product in the thrombus remodeling, may have prognostic value for AAA. This study investigated the interrelation between plasma D-dimer level, ILT volume, AAA size and progression. MAIN METHODS: This was a retrospective observational study that involved 181 patients with infra-renal AAA. They were divided into small and large AAA groups according to AAA diameter. 24 of them had repeated abdominal computed tomography angiography (CTA) scan and were divided into slow-growing and fast-growing AAA groups according to the median value of AAA growth rate. Baseline and follow-up plasma D-dimer level, maximum diameter of AAA, total infra-renal aortic volume and ILT volume were analyzed. KEY FINDINGS: Plasma D-dimer level was positively correlated with ILT volume (R = 0.382, P < 0.001) and maximum diameter of AAA (R = 0.442, P < 0.001). Increasing value of plasma D-dimer was positively associated with the accelerated growth rate of AAA (R = 0.720, P < 0.01). ILT volume showed positive correlation with maximum diameter (R = 0.859, P < 0.001) and growth rate of AAA (R = 0.490, P < 0.05). After adjusting the baseline ILT volume, the positive correlations remained to be statistically significant between plasma D-dimer level and AAA size (R = 0.200, P < 0.05), as well as increasing value of plasma D-dimer and growth rate of AAA (R = 0.642, P < 0.05). SIGNIFICANCE: Plasma D-dimer level reflected ILT burden in AAAs. Plasma D-dimer level and ILT volume were positively correlated with AAA size. Increasing value of plasma D-dimer and baseline ILT volume could be predictors of AAA progression.

Safe limits of contrast vary with hydration volume for prevention of contrast-induced nephropathy after coronary angiography among patients with a relatively low risk of contrast-induced nephropathy.

BACKGROUND: Few studies have investigated the safe limits of contrast to prevent contrast-induced nephropathy (CIN) based on hydration data. We aimed to investigate the relative safe maximum contrast volume adjusted for hydration volume in a population with a relatively low risk of CIN. METHODS AND RESULTS: The ratios of contrast volume-to-creatinine clearance (V/CrCl) and hydration volume to body weight (HV/W) were determined in patients undergoing cardiac catheterization. Receiver-operator characteristic curve analysis based on the maximum Youden index was used to identify the optimal cutoff for V/CrCl in all patients and in HV/W subgroups. Eighty-six of 3273 (2.6%) patients with mean CrCl 71.89±27.02 mL/min developed CIN. Receiver-operator characteristic curve analysis indicated that a V/CrCl ratio of 2.44 was a fair discriminator for CIN in all patients (sensitivity, 73.3%; specificity, 70.4%). After adjustment for other confounders, V/CrCl >2.44 continued to be significantly associated with CIN (adjusted odds ratio, 4.12; P<0.001) and the risk of death (adjusted hazard ratio, 2.62; P<0.001). The mean HV/W was 12.18±7.40. We divided the patients into 2 groups (HV/W ≤12 and >12 mL/kg). The best cutoff value for V/CrCl was 1.87 (sensitivity, 67.9%; specificity, 64.4%; adjusted odds ratio, 3.24; P=0.011) in the insufficient hydration subgroup (HV/W, ≤12 mL/kg; CIN, 1.32%) and 2.93 (sensitivity, 69.0%; specificity, 65.0%; adjusted odds ratio, 3.04; P=0.004) in the sufficient hydration subgroup (HV/W, >12 mL/kg; CIN, 5.00%). CONCLUSIONS: The V/CrCl ratio adjusted for HV/W may be a more reliable predictor of CIN and even long-term outcomes after cardiac catheterization. We also found a higher best cutoff value for V/CrCl to predict CIN in patients with a relatively sufficient hydration status, which may be beneficial during decision-making about contrast dose limits in relatively low-risk patients with different hydration statuses.

Preprocedural N-terminal pro-brain natriuretic peptide (NT-proBNP) is similar to the Mehran contrast-induced nephropathy (CIN) score in predicting CIN following elective coronary angiography.

BACKGROUND: N-terminal pro-brain natriuretic peptide (NT-proBNP) has been associated with important risk factors for contrast-induced nephropathy (CIN). However, few studies have investigated the predictive value of NT-proBNP itself. This study investigated whether levels of preprocedural NT-proBNP could predict CIN after elective coronary angiography as effectively as the Mehran CIN score. METHODS AND RESULTS: We retrospectively observed 2248 patients who underwent elective coronary angiography. The predictive value of preprocedural NT-proBNP for CIN was assessed by receiver operating characteristic and multivariable logistic regression analysis. The 50 patients (2.2%) who developed CIN had higher Mehran risk scores (9.5 ± 5.1 versus 4.8 ± 3.8), and higher preprocedural levels of NT-proBNP (5320 ± 7423 versus 1078 ± 2548 pg/mL, P<0.001). Receiver operating characteristic analysis revealed that NT-proBNP was not significantly different from the Mehran CIN score in predicting CIN (C=0.7657 versus C=0.7729, P=0.8431). An NT-proBNP cutoff value of 682 pg/mL predicted CIN with 78% sensitivity and 70% specificity. Multivariable analysis suggested that, after adjustment for other risk factors, NT-proBNP >682 pg/mL was significantly associated with CIN (odds ratio: 4.007, 95% CI: 1.950 to 8.234; P<0.001) and risk of death (hazard ratio: 2.53; 95% CI: 1.49 to 4.30; P=0.0006). CONCLUSIONS: Preprocedural NT-proBNP >682 pg/mL was significantly associated with the risk of CIN and death. NT-proBNP, like the Mehran CIN score, may be another useful and rapid screening tool for CIN and death risk assessment, identifying subjects who need therapeutic measures to prevent CIN.

[2-Bromoethylamine protects vascular endothelium by inhibiting SSAO activity in diabetic rats].

The purpose of this study was to investigate the change of aortic semicarbazide-sensitive amine oxidase (SSAO) activity in diabetic rats and examine the effect of 2-bromoethylamine (2-BEA) on SSAO activity and vascular endothelium in diabetic rats. SSAO was prepared from rat aorta. For assessment of the inhibitory effect, the enzymes were preincubated in the presence of different concentrations of 2-BEA before the addition of benzylamine in vitro. Type 1 diabetic rat model was induced by a single intraperitoneal injection of streptozotocin (STZ). Sprague Dawley (SD) rats were randomly divided into normal control group (NC), diabetic model group (DM), 2-BEA 5 mg/kg group, 2-BEA 20 mg/kg group (n = 10 in each group). 2-BEA was administered daily via intraperitoneal injection for 8 weeks. At the end of 8 weeks, blood sample was collected from the abdominal aorta. Plasma nitric oxide (NO) was determined by nitrate reductase method. Plasma endothelin-1 (ET-1) was determined by radioimmunoassay. Aorta SSAO was determined by high performance liquid chromatography. The aorta was prepared to observe morphological changes and ultramicroscopic structures. The results were as follows: Compared with NC group, aortic SSAO activity and the plasma ET-1 were significantly increased (P < 0.01), and plasma NO was significantly decreased (P < 0.01) in DM group. 2-BEA decreased plasma ET-1 and elevated plasma NO by inhibiting aortic SSAO activity in diabetic rats (P < 0.01), and 2-BEA 20 mg/kg group was more significant than 2-BEA 5 mg/kg group (P < 0.05). Endothelial injury of 2-BEA group rats was less serious than DM group. These results suggest that 2-BEA protect aortic endothelium by inhibiting aortic SSAO activity.

[Association between high-sensitivity C-reactive protein and contrast-induced nephropathy after primary percutaneous coronary intervention].

OBJECTIVE: To explore the association between high-sensitivity C-reactive protein (hs-CRP) and contrast-induced nephropathy (CIN) in patients with ST-segment elevated myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI) . METHODS: A total of 220 STEMI patients undergoing primary PCI from Guangdong general hospital were recruited. Patients were divided into four groups according to the quartile of hs-CRP (Q1 group:hs-CRP < 6.26 mg/L,Q2 group:6.26-14.44 mg/L, Q3 group:14.45-33.08 mg/L, Q4 group:hs-CRP > 33.08 mg/L) . Baseline data, CIN incidence and other in-hospital outcomes were compared among groups. CIN was defined as an increase in serum creatinine of more than 5 mg/L from baseline within 48-72 hours after contrast media exposure. Receiver operator characteristics (ROC) curves and multivariate logistic regression were used to assessed the correlation between hs-CRP and CIN. RESULTS: CIN occurred in 21 (9.8%) patients. CIN incidence of hs-CRP quartitles were 1.8%(1/55), 1.8% (1/55), 14.5% (8/55) and 20.0% (11/55) (P-trend < 0.01), respectively. In-hospital death (P-trend > 0.05) , required renal replace therapy (P-trend > 0.05) were similar among groups. ROC analysis revealed that the optimal cutoff value of hs-CRP to predict the onset of CIN was 16.85 mg/L (sensitivity: 81.0%, specificity: 61.8%, AUC: 0.748). Univariate logistic analysis showed that hs-CRP was strongly related with CIN incidence (OR = 6.88,95%CI:2.23-21.21, P < 0.01). Multivariate logistic regression analysis showed that after adjusting other traditional risk factors including female gender, anemia, ACEI/ARB use, IABP support, LVEF < 40%, age > 75 years, baseline eGFR and diabetes, hs-CRP > 16.85 mg/L was still a significant independent predictor of CIN in patients with STEMI undergoing primary PCI. Additionally, age > 75 years (OR = 7.27,95%CI:1.85-28.63, P < 0.01), eGFR (OR = 6.38,95% CI:1.48-27.41, P < 0.05) were also independent risk factors of CIN. CONCLUSIONS: hs-CRP is positively correlated with CIN incidence. STEMI patients with higher hs-CRP level post PCI is at higher risk of developing CIN.

[Increased platelet-leukocyte aggregates in patients with acute coronary syndrome].

OBJECTIVE: To compare the platelet-leukocyte-aggregates (PLAs) level among patients with acute coronary syndrome (ACS) and stable angina pectoris (SAP). METHODS: Hospitalized patients were divided into three groups [ACS group (n=86), SAP group (n=54), the control group with 46 patients without coronary artery disease]. PLAs were measured by flow cytometry at admission before coronary angiography. ACS patients were further divided into low-risk group (0-108 points) and high-risk group (>109 points) according to GRACE scores at admission. PLA, platelet-monocyte aggregations (PMA), platelet-neutrophil aggregations (PNA), platelet-lymphocyte aggregations (PlyA) and hs-CRP values were compared among groups. RESULTS: PLA (4.40%±3.08%), PMA (33.6%±21.5%), PNA (3.76%±5.06%), PLyA (2.03%±1.27%) and hs-CRP [5.75 (3.49, 9.15)] levels in ACS group were significantly higher than those in SAP and control groups (all P<0.05). PLA was also significantly higher in high-risk group than in the low-risk group (44.8%±18.0% vs. 13.0%±6.3%, P<0.01). Spearman correlation analysis showed that hs-CRP was positively correlated with PMA (r=0.547, P<0.01) and GRACE score is positively correlated with PMA, PLA, PNA and PlyA (r=0.746, 0.652, 0.460, respectively, all P<0.01). CONCLUSION: PLAs is increased in ACS patients and higher PMA level is related with the unstable coronary syndrome in ACS patients. Increased PMA, PLA, PNA and PlyA levels is associated with higher GRACE score in ACS patients.