Concomitant impact of high-sensitivity C-reactive protein and renal dysfunction in patients with acute myocardial infarction

Predictive Value of Baseline High-Sensitivity C-Reactive Protein Level and Renal Function for Patients With Acute Coronary Syndrome Undergoing Aggressive Lipid-Lowering Therapy: A Subanalysis of HIJ-PROPER

The systematic inflammatory response might confound renal impairment, and both have been reported to affect clinical outcomes after acute coronary syndrome. We examined the impacts of the high-sensitivity C-reactive protein (hsCRP) level and estimated glomerular filtration rate level on the prognosis for acute coronary syndrome patients who underwent aggressive lipid-lowering therapy in contemporary practice. This was a subanalysis of the HIJ-PROPER study, and 1,734 patients were enrolled. Patients were divided into 4 groups using an hsCRP value of 10mg/L and an estimated glomerular filtration rate value of 60 ml/min/1.73 m² as the cut-off points. Groups were defined as follows: group A, low hsCRP and normal or mild renal impairment; group B, low hsCRP and renal impairment; group C, high hsCRP and normal or mild renal impairment; and group D, high hsCRP and renal impairment. The primary end point was defined as the composite of all-cause death, nonfatal myocardial infarction, nonfatal stroke, and unstable angina or coronary revascularizations. The median follow-up period was 3.9years, and the follow-up rate was 99%. Compared with group A, the 2 higher hsCRP groups (groups C and D) showed a significantly higher incidence of primary end points (hazard ratio 1.36, 95% confidence interval 1.12 to 1.65, p = 0.002; and hazard ratio 1.40, 95% CI 1.10 to 1.80, p = 0.008). Such a difference was not found compared with group B. In conclusion, patients with higher hsCRP levels had worse prognoses regardless of renal impairment and aggressive lipid-lowering therapy.

Increased Thrombogenicity in Chronic Renal Failure in a Rat Model Induced by 5/6 Ablation/Infarction

PURPOSE

Abnormalities in hemostasis and coagulation have been suggested in chronic renal failure (CRF). In this study, we compared processes of thrombus formation between rats with CRF and those with normal kidney function.

MATERIALS AND METHODS

CRF was induced by 5/6 ablation/infarction of the kidneys in Sprague-Dawley rats, and surviving rats after 4 weeks were used. Ferric chloride (FeCl₃)-induced thrombosis in the carotid artery was induced to assess thrombus formation. Whole blood clot formation was evaluated using rotational thromboelastometry (ROTEM). Platelet aggregation was assessed with impedance platelet aggregometry.

RESULTS

FeCl₃-induced thrombus formation was initiated faster in the CRF group than in the control group (13.2±1.1 sec vs. 17.8±1.0 sec, p=0.027). On histological examination, the maximal diameters of thrombi were larger in the CRF group than in the control group (394.2±201.1 μm vs. 114.0±145.1 μm, p=0.039). In extrinsic pathway ROTEM, the CRF group showed faster clot initiation (clotting time, 59.0±7.3 sec vs. 72.8±5.0 sec, p=0.032) and increased clot growth kinetics (α angle, 84.8±0.2° vs. 82.0±0.6°, p=0.008), compared to the control group. Maximal platelet aggregation rate was higher in the CRF group than in the control group (58.2±0.2% vs. 44.6±1.2%, p=0.006).

CONCLUSION

Our study demonstrated that thrombogenicity is increased in rats with CRF. An activated extrinsic coagulation pathway may play an important role in increasing thrombogenicity in CRF.

BET protein inhibition mitigates acute myocardial infarction damage in rats via the TLR4/TRAF6/NF-κB pathway

Acute myocardial infarction (AMI) is among the most serious cardiovascular diseases and is a leading cause of mortality in developed countries. Previous studies have indicated the central role played by the bromodomain (BRD) proteins, which belong to the BRD and extra-terminal (BET) family, in gene control during heart failure pathogenesis. In addition, BET inhibition has been shown to suppress cardiomyocyte hypertrophy. However, the role of BET proteins in myocardial infarction remains unclear. The present study aimed to investigate whether BETs inhibition mitigates AMI, and explore the molecular mechanism underlying this effect. A rat model of acute myocardial infarction was established, and rats were divided into the sham, AMI and AMI + JQ1 groups. JQ1, a well-known selective BRD inhibitor, was used to suppress BET domain family activity. The mRNA and protein expression levels of BRD2, BRD3 and BRD4 were evaluated using quantitative polymerase chain reaction and western blot analysis, respectively. In addition, the expression levels of markers of cardiac damage were determined using commercial kits. The results indicated that BRD2 and BRD4 mRNA and protein expression levels were significantly increased in the AMI group compared with those in the sham group. In addition, BET inhibition decreased AMI damage in vivo by reversing cardiac function injury, decreasing serum lactate dehydrogenase and creatine kinase-MB isozyme activity, in addition to decreasing the expression levels of high-sensitivity C-reactive protein and interleukin-6. Furthermore, the results suggested that Toll-like receptor 4 (TLR4) signaling was activated by the increased expression of TLR4, TNF receptor-associated factor 6 (TRAF6) and nuclear factor (NF)-κB during AMI. However, JQ1 treatment suppressed TLR4 signaling activation. In conclusion, the present results demonstrated that the inhibition of BET family proteins suppresses AMI, and that this effect was partially mediated by the inhibition of TLR4/TRAF6/NF-κB signaling.

The scientific achievements of the decades in Korean Acute Myocardial Infarction Registry

The Korea Acute Myocardial Infarction Registry (KAMIR) was the first nationwide registry data collection designed to track outcomes of patients with acute myocardial infarction (AMI). These studies reflect the current therapeutic approaches and management for AMI in Korea. The results of KAMIR could help clinicians to predict the prognosis of their patients and identify better diagnostic and treatment tools to improve the quality of care. The KAMIR score was proposed to be a predictor of the prognosis of AMI patients. Triple antiplatelet therapy, consisting of aspirin, clopidogrel and cilostazol, was effective at preventing major adverse clinical outcomes. Drug-eluting stents were effective and safe in AMI patients with no increased risk of stent thrombosis. Statin therapy was effective in Korean AMI patients, including those with very low levels of low density cholesterol. The present review summarizes the 10-year scientific achievements of KAMIR from admission to outpatient care during long-term clinical follow-up.