The effect of atorvastatin on haemostatic parameters in apparently healthy dogs

OBJECTIVE

To determine the effect of atorvastatin on haemostatic parameters as measured by prothrombin time, activated partial thromboplastin time and thromboelastography in apparently healthy dogs administered 2 mg/kg orally once daily for 1 week.

MATERIALS AND METHODS

Prospective study of 20 apparently healthy client-owned dogs at a small animal specialty hospital. Dogs had a baseline complete blood count, serum chemistry profile, fibrinogen, platelet count, prothrombin time, activated partial thromboplastin time and thromboelastography performed. Each dog was then administered approximately 2 mg/kg of atorvastatin orally once daily for 1 week, and the laboratory tests were repeated. Adverse effects attributed to atorvastatin were recorded.

RESULTS

All 20 enrolled dogs completed the study. Dogs received a median dose of 2.06 mg/kg (range 1.94 to 2.44 mg/kg) atorvastatin once daily, which was associated with a significant increase in pulse rate, mean corpuscular haemoglobin concentration, albumin and a significant decrease in mean corpuscular volume, cholesterol and lipase values compared with baseline. On thromboelastography, there was a significant increase in maximum amplitude, G, coagulation index, amplitude at 30 minutes, amplitude at 60 minutes and significant decrease in percentage of clot lysed at 30 minutes and percentage of clot lysed at 60 minutes values compared with baseline. Six dogs had a noticeable increase in appetite.

CLINICAL SIGNIFICANCE

The results of this study suggest that atorvastatin may produce a procoagulant effect in dogs, although the clinical significance is unclear. Polyphagia was the most commonly reported adverse effect.

Preoperative atorvastatin reduces bleeding and blood products use in patients undergoing on-pump coronary artery bypass grafting

AIMS

Statins are a widely recognized weapon in the primary and secondary prevention of coronary artery disease for their pleiotropic effects. However, recent reports from the cerebrovascular and pharmacological literature are insinuating concerns about a potential increase in the haemorrhagic risk among statin users.The effect of statins in postoperative bleeding should be carefully investigated in major cardiac surgery that exposes per se to risk of bleeding.

METHODS

In this retrospective cohort study, we evaluated 441 patients who received atorvastatin until surgery and 213 patients who had never been treated with statins, undergoing elective primary isolated on-pump coronary artery bypass grafting. Postoperative bleedings, blood products use and complications were monitored during hospitalization.

RESULTS

Preoperative and intraoperative variables were similar between groups. Early and overall postoperative bleedings were reduced among statin users, who had lower C-reactive protein values in the first postoperative day. Atorvastatin carries a strong protective effect against major bleedings, with a propensity score-adjusted odds ratio of 0.28 (P < 0.01). Also, blood products use for statin-treated patients was lower compared with controls, with fewer transfused patients and fewer red-packed cells units per transfused patient.

CONCLUSION

Preoperative atorvastatin use is associated with reduced risk of bleeding and blood products use after coronary artery bypass grafting, likely due to a reduction in the postoperative inflammatory response. Statin continuation at the highest tolerable dose should be encouraged before cardiac surgery. The preoperative use of statins in cardiac surgery as 'bleeding-preventers' might have profound clinical implications.

Neutrophil to Lymphocyte Ratio as a Predictor of Restenosis After Angioplasty and Stenting for Asymptomatic Carotid Stenosis

The inflammatory response plays a vital role in the development of in-stent restenosis (ISR) after carotid angioplasty and stenting (CAS). The neutrophil to lymphocyte ratio (NLR) has been suggested as a sensitive inflammatory marker. We explored the association between NLR and ISR in CAS patients. A total of 427 patients who underwent CAS were enrolled. Neutrophil to lymphocyte ratio was measured before the procedure. Clinical examination and radiographic evaluation were performed at 6 months and annually after the procedure. In-stent restenosis was defined as ≥50% stenosis in the treated lesion. Cox regression was used to identify predictors of ISR after CAS. Of the 459 arteries (in 427 patients) with CAS, 72 (15.7%) were identified with ISR during a mean follow-up of 14.6 (19.1) months (range, 0.7-120.7 months). Increased NLR (≥2.13) was significantly related to ISR in patients with asymptomatic stenosis ( P = .001). However, significance was not observed in symptomatic stenosis. On multivariate analysis, baseline NLR ≥ 2.13 (hazard ratio [HR], 2.74; 95% confidence interval [CI], 1.46-5.14), smoking (HR, 1.99; 95% CI, 1.11-3.58), residual stenosis (HR, 1.12; 95% CI, 1.09-1.15), and baseline glucose level (HR, 1.01; 95% CI, 1.01-1.02) were associated with ISR. Elevated NLR may be a predictor of ISR after CAS for asymptomatic stenosis.

The effect of statin therapy on plaque regression following acute coronary syndrome: a meta-analysis of prospective trials

OBJECTIVE

To investigate the effect of statins on plaque regression after acute coronary syndrome (ACS).

METHODS

We carried out a meta-analysis to assess the change in plaque and plaque components in patients with ACS under statin therapy. This meta-analysis combined data of 1623 participants from eight randomized-controlled trials and seven observational studies.

RESULTS

The benefits of high-intensity statin therapy on plaque regression occurred after 6 months [standardized mean difference (SMD): -0.27; 95% confidence interval (CI): -0.43 to -0.12; P=0.0006] and were sustained over 12 months (SMD: -0.14; 95% CI: -0.25 to -0.03; P=0.01). No significant decrease was observed in the plaque volume and percent plaque volume under low-dose statin treatment. After 6 months of intensive statin treatment, the plaque volume reduced significantly in patients whose follow-up LDL cholesterol levels did (SMD: -0.16; 95% CI: -0.29 to -0.03; P=0.02) or did not (SMD: -0.21; 95% CI: -0.32 to -0.09; P=0.0007) decrease to 70 mg/dl or less. There was no significant change in plaque composition volumes, but an increase was found in the percent dense calcium volume of 1.31% (95% CI: 0.55-2.07%; P=0.0007).

CONCLUSION

Intensive statin therapy duration over 6 months may be as important as achieved LDL-C of less than or equal to 70 mg/dl in plaque regression following ACS. Intensive statin treatment may lead to an earlier regression compared with low-dose statin therapy.

Perioperative Statin Therapy for Patients Undergoing Coronary Artery Bypass Grafting

Coronary artery bypass grafting is associated with an intense systemic inflammatory response, which is linked to postoperative complications. Beyond lipid lowering, statins exert a constellation of beneficial actions, including an antiinflammatory role, known as pleiotropic effects. There is increasing evidence that perioperative statin therapy improves outcomes in patients undergoing coronary artery bypass grafting. Statins are underused in the coronary artery bypass grafting population, because perioperative discontinuation remains a common practice. This article provides an extensive review of the available literature on the effect of perioperative statin therapy on post–coronary artery bypass grafting outcomes and weighs the evidence for the concerns about increased incidence of statin-related adverse effects in this setting.

[Cognitive dysfunction after coronary artery bypass grafting]

Despite the advances in surgical and anesthetic techniques for coronary artery bypass grafting (CABG), the incidence of neurological complications, including postoperative cognitive dysfunction (POCD), remains high. CABG is performed more often in elderly patients with severe comorbidities. However, comprehensive prevention measures and POCD rehabilitation have not yet been developed. Physical training is an effective and safe method for correcting endothelial dysfunction, severe systemic inflammatory response syndrome, lipid peroxidation, i.e. mechanisms contributing to the development and severity of POCD.

Statins suppress glucose-induced plasminogen activator inhibitor-1 expression by regulating RhoA and nuclear factor-κB activities in cardiac microvascular endothelial cells

The aim of this study was to investigate the possible proinflammatory signaling pathways involved in statin inhibition of glucose-induced plasminogen activator inhibitor-1 (PAI-1) expression in cardiac microvascular endothelial cells (CMECs). Primary rat CMECs were grown in the presence of 5.7 or 23 mmol/L glucose. PAI-1 mRNA and protein expression levels were measured by realtime polymerase chain reaction, Western blotting and enzyme-linked immunosorbent assay, respectively. A pull-down assay was performed to determine RhoA activity. IκBα protein expression was measured by Western blotting, nuclear factor (NF)-κB activation was detected by electrophoretic mobility shift assay and its transcription activity was determined by a dual luciferase reporter gene assay. PAI-1 mRNA and protein expression levels were both increased with high glucose concentrations, but they were significantly suppressed by simvastatin and atorvastatin treatment (P < 0.01) and the effects were reversed by mevalonate (100 μmol/L) and geranylgeranyl pyrophosphate (10 μmol/L) but not farnesyl pyrophosphate (10 μmol/L). Such effects were similar to those of a RhoA inhibitor, C3 exoenzyme (5 μg/mL), inhibitors of RhoA kinase (ROCK), Y-27632 (10 μmol/L) and hydroxyfasudil (10 μmol/L) and an NF-κB inhibitor, BAY 11-7082 (5 μmol/L). High glucose-induced RhoA and NF-κB activations in CMECs were both significantly inhibited by statins (P < 0.01). Simvastatin and atorvastatin equally suppress high glucose-induced PAI-1 expression. These effects of statins may occur partly by regulating the RhoA/ROCK-NF-κB pathway. The multifunctional roles of statins may be particularly beneficial for patients with metabolic syndrome.

The Association of Interleukin 6−634C/G Polymorphism With Left Atrial Thrombus and Severe Spontaneous Echocontrast in Patients With Atrial Fibrillation

Atrial fibrillation (AF) not only is an independent risk factor for death but also confers significant risk of morbidity from stroke associated with left atrial thrombus. The association of interleukin 6 ( IL-6) polymorphism with thrombus in AF has not been investigated before. We carried out a case–control study in Han Chinese. The IL-6 −634C/G genotypes of 31 patients with thrombus and 45 patients without thrombus were detected by polymerase chain reaction and restriction fragment length polymorphism. The frequencies of the IL-6 genotypes (CC, CG, and GG) were 29.03%, 54.54%, and 16.13% for the patients with thrombus, and 55.56%, 40.00%, and 4.44% for the patients without thrombus, respectively ( P = .0391). Compared with the CC genotype, the G allele carriers (CG + GG) had a 2.79-fold increased risk of thrombus or severe spontaneous echocontrast (SEC). These results suggest that IL-6 −634C/G polymorphism is associated with thrombus and severe SEC, and the G allele is an independent risk for thrombus and severe SEC in Han Chinese patients with AF.