A Review of the Relationship Between CTRP Family and Coronary Artery Disease

Purpose of Review

In recent years, a family of adiponectin paralogs designated as C1q/TNF-related protein (CTRP) has attracted increasing attention. They are inflammatory adipocytokines mostly secreted from epicardial adipose tissue, which modulate the development and prognosis of coronary artery disease (CAD). This review summarizes the pathophysiological roles of individual members of the CTRP superfamily in the development of CAD.

Recent Findings

Recent studies have revealed how members of the CTRP family, CTRP1, CTRP3, CTRP5, CTRP9, CTRP12, and CTRP13, can influence both development and progression of CAD by modulating metabolic pathways, influencing immuno-inflammatory response, and regulating cardiovascular functions.

Summary

Research to date has not been sufficient to answer the specific mechanism of the CTRP family in the occurrence and development of CAD. This review explores the evidence of CTRP superfamily regulating different pathophysiology stages of CAD through the immuno-inflammation, glucose and lipid metabolism, and vascular endothelial function.

Elevated Baseline Serum Fibrinogen: Effect on 2-Year Major Adverse Cardiovascular Events Following Percutaneous Coronary Intervention

Background

Elevated fibrinogen is associated with short‐term major adverse cardiovascular events (MACE) after percutaneous coronary intervention, but the relation with late MACE is unknown.

Methods and Results

Baseline demographics and 2‐year MACE were recorded among subjects undergoing nonemergent percutaneous coronary intervention. A total of 332 subjects (66.6±19.5 years, 69.9% male, 25.3% acute coronary syndrome) were enrolled. Two‐year MACE (periprocedural myocardial infarction 9.0%, rehospitalization 6.3%, revascularization 12.7%, non–periprocedural myocardial infarction 4.5%, stent thrombosis 0.9%, stroke 1.8%, and death 0.6%) were associated with higher fibrinogen (352.8±123.4 mg/dL versus 301.6±110.8 mg/dL; P<0.001), longer total stent length (40.1±25.3 mm versus 32.1±19.3 mm; P=0.004), acute coronary syndrome indication (38.7% versus 17.8%; P<0.001), number of bare‐metal stents (0.5±1.1 versus 0.2±0.5; P=0.002), and stent diameter ≤2.5 mm (55.8% versus 38.4%, P=0.003). No relation between platelet reactivity and 2‐year MACE was observed. Fibrinogen ≥280 mg/dL (odds ratio [OR] 3.0, confidence interval [CI], 1.6–5.4, P<0.001), total stent length ≥32 mm (OR 2.2, CI, 1.3–3.8, P<0.001), acute coronary syndrome indication (OR 4.1, CI, 2.3–7.5, P<0.001), any bare‐metal stents (OR 3.2, CI, 1.6–6.1, P<0.001), and stent diameter ≤2.5 mm (OR 2.0, CI, 1.2–3.5, P=0.010) were independently associated with 2‐year MACE. Following a landmark analysis excluding periprocedural myocardial infarction, fibrinogen ≥280 mg/dL remained strongly associated with 2‐year MACE (37.0% versus 17.4%, log‐rank P<0.001).

Conclusions

Elevated baseline fibrinogen level is associated with 2‐year MACE after percutaneous coronary intervention. Acute coronary syndrome indication for percutaneous coronary intervention, total stent length implanted, and use of bare‐metal stents or smaller‐diameter stents are also independently associated with 2‐year MACE, while measures of on‐thienopyridine platelet reactivity are not.

Association between Coagulation Function and Cerebral Microbleeds in Ischemic Stroke Patients with Atrial Fibrillation and/or Rheumatic Heart Disease

Cerebral microbleeds (CMBs), which indicate hemorrhage-prone disease, may associate with hemostatic abnormalities, but the association between CMBs and coagulation function is uncertain. We aimed to examine this possible association. The following coagulation function indicators were evaluated in 85 consecutive ischemic stroke patients diagnosed with atrial fibrillation and/or rheumatic heart disease: prothrombintime (PT), activated partial thromboplastin time (APTT), and levels of D-dimer and fibrinogen. Indicators were assessed within 24 h after admission. CMBs were identified based on published criteria by two experienced stroke neurologists working independently. PT, APPT, and levels of D-dimer and fibrinogen were compared between patients with and without CMBs using univariate and multivariate analysis. CMBs were detected in 48 patients (56.5%), and fibrinogen levels in these patients were independently and significantly higher than in patients without CMBs after adjustment (OR 2.16, 95% CI 1.20-3.90, P=0.01), whereas the two types of patients did not differ significantly in PT, APPT, or D-dimer levels. The presence of CMBs in ischemic stroke patients with atrial fibrillation and/or rheumatic heart disease is associated with elevated levels of fibrinogen. Larger prospective studies are needed to verify this association and explore the mechanisms involved.

Effect of Serum Fibrinogen, Total Stent Length, and Type of Acute Coronary Syndrome on 6-Month Major Adverse Cardiovascular Events and Bleeding After Percutaneous Coronary Intervention

This study evaluated the relation between baseline fibrinogen and 6-month major adverse cardiovascular events (MACE) and bleeding after percutaneous coronary intervention (PCI). Three hundred eighty-seven subjects (65.6 ± 16.1 years, 69.5% men, 26.9% acute coronary syndrome [ACS]) who underwent PCI with baseline fibrinogen and platelet reactivity (VerifyNow P2Y12 assay, Accumetrics, San Diego, California) measured were enrolled. Fibrinogen (368.8 ± 144.1 vs 316.8 ± 114.3 mg/dl; p = 0.001), total stent length (TSL; 44.5 ± 25.0 vs 32.2 ± 20.1 mm; p <0.001), and ACS presentation (40.6% vs 23.9%; p = 0.005) were independently associated with 6-month MACE rates (17.8%: myocardial infarction 9.8%, rehospitalization for ACS 3.6%, urgent revascularization 3.6%, stroke 0.5%, and death 0.3%). Measures of platelet reactivity were not associated with 6-month MACE. After multivariate analysis, fibrinogen ≥280 mg/dl (odds ratio [OR] 2.60, 95% CI 1.33 to 5.11, p = 0.005), TSL ≥32 mm (OR 3.21, 95% CI 1.82 to 5.64, p <0.001), and ACS presentation (OR 2.58, 95% CI 1.45 to 4.61, p = 0.001) were associated with higher 6-month MACE. In 271 subjects receiving chronic P2Y12 inhibitor therapy, 6-month Thrombolysis In Myocardial Infarction bleeding after PCI was 7.0%, but no difference in fibrinogen level (338.3 ± 109.7 vs 324.3 ± 113.8 mg/dl, p = 0.60) stratified by Thrombolysis In Myocardial Infarction bleeding was observed. In conclusion, elevated serum fibrinogen, ACS presentation, and longer TSL are independently associated with higher 6-month MACE after PCI, whereas no association with on-thienopyridine platelet reactivity and 6-month MACE was observed. Post-PCI bleeding was not associated with lower fibrinogen level.

Impact of diabetes on fibrinogen levels and its relationship with platelet reactivity and coronary artery disease: A single-centre study

BACKGROUND

Previous reports have suggested an association between elevated fibrinogen and CAD. Few studies have so far investigated the impact of diabetes on fibrinogen levels and its association with coronary artery disease (CAD) and platelet reactivity in diabetic patients that are therefore the aims of the current study.

METHODS

We measured fibrinogen in 3280 consecutive patients undergoing coronary angiography. Samples were collected at admission for fibrinogen levels assessment. Coronary disease was defined for at least 1 vessel stenosis >50% as evaluated by QCA.

RESULTS

Diabetes was observed in 1201 out of 3280 patients. Diabetic patients were older with more hypercholesterolemia, hypertension, higher BMI, more renal failure, previous MI or coronary revascularization (p<0.001, respectively) and smoking (p=0.001). Diabetic patients were more often on ACE-inhibitors, ARBs, b-blockers, calcium-antagonists, diuretics, statins (p<0.001, respectively), and ASA (p=0.004). Diabetic patients displayed higher glycaemia and HbA1c (p<0.001), higher creatinine and triglycerides (p<0.001) but lower total and HDL cholesterol (p<0.001) and haemoglobin (p<0.001). Diabetic patients had higher fibrinogen levels (p=0.003), however neither diabetes nor glucose homeostasis parameters resulted as independent predictors of hyperfibrinogenemia. Furthermore, among diabetic patients, higher fibrinogen levels did not affect platelet reactivity and were not associated with the prevalence of CAD (adjusted OR[95%CI]=0.99 [0.82-1.19], p=0.9). Similar results were found for severe CAD (adjusted OR[95%CI]=0.94 [0.82-1.08], p=0.40).

CONCLUSIONS

Our study showed that diabetes and glycaemic control are not independent predictors of hyperfibrinogenemia. Among diabetic patients, elevated fibrinogen is not associated with platelet reactivity and the prevalence and extent of CAD.

Lack of association between clopidogrel responsiveness tested using point-of-care assay and prognosis of patients with coronary artery disease

Dual antiplatelet therapy is important treatment modality across the spectrum of coronary artery disease manifestations. However, a significant number of patients do not have a completely effective response to clopidogrel. This study assessed the impact of response after clopidogrel with Verify Now device on prognosis on patients undergoing coronary interventions. Consecutive patients following percutaneous coronary intervention were prospectively enrolled. A loading dose of 600 mg of clopidogrel was administered before or during PCI. Blood samples were drawn within 24 h after clopidogrel administration. The effect of clopidogrel was measured using VerifyNow. All patients were evaluated at 6 months. The primary end-point was the combination of death, MI and stroke. 378 patients (69.3 % men and 30.7 % women) were enrolled. The mean age was 67.2 ± 12.8 years, BMI 28.9 ± 17.7, and 116 patients had diabetes (30.7 %). During the 6-months follow-up 30 patients (7.94 %) experienced a monitored end-point: 12 patients (3.17 %) had MI; five patients (1.32 %) strokes and 15 patients (3.97 %) died. The remaining 248 patients (71.26 %) were end-point free. Factors associated with a poor prognosis were: leukocytes (OR 1.7 [1.2-2.4], p < 0.01), creatinine (OR 1.4 [1.1-2.5], p < 0.05) and at a borderline level the presence of AA allele of gene CYP2C19*2 (OR 2.5 [0.99-4.1], p = 0.052). The results using VerifyNow were similar between both groups (Group End-point: 208.5 ± 85.5, group No end-point 203.1 ± 91.3) and failed to show any prognostic value (OR 1.00 [0.992-1.007], p = 0.9). The measurement of clopidogrel efficacy using VerifyNow had no prognostic value for our unselected cohort of patients after PCI.

Assessment of platelet inhibition by point-of-care testing in neuroendovascular procedures

Antiplatelet agents are an important component of the preventive strategies currently used in clinical practice to minimize the risk of thromboembolic events during and after endovascular procedures. Because of the variability in the response to antiplatelet agents, measuring the degree of platelet inhibition may help identify and properly treat poor responders. POC testing is defined as diagnostic testing at or near the site of patient care. Knowledge of the specifics of these devices among practicing neurointerventionalists is relatively limited. In this article, the different POC devices available are presented, and their clinical utility in relation to endovascular procedures is discussed.

Efficacy and Safety of Ticagrelor: A Reversible P2Y12 Receptor Antagonist

Objective:

To summarize the pharmacokinetic and pharmacodynamic properties of ticagrelor, a selective P2Y12 receptor antagonist, and evaluate its role in the treatment of patients with acute coronary syndromes (ACS).

Data Sources:

A literature search was conducted in MEDLINE (1966–November 2009), International Pharmaceutical Abstracts (1970–November 2009), and EMBASE (1990–November 2009) using the MeSH terms and key words AZD6140, ticagrelor, P2Y12 receptor antagonist, cardiovascular disease, ACS, atherothrombosis, and platelets.

Study Selection And Data Extraction:

Selected studies evaluated the pharmacology, pharmacokinetics, pharmacodynamics, safety, and efficacy of ticagrelor for the treatment of ACS.

Data Synthesis:

Ticagrelor selectively and reversibly blocks the P2Y12 receptor, inhibiting platelet aggregation and preventing amplification of platelet activation. Optimal dosing strategy as determined by ticagrelor's pharmacokinetic and pharmacodynamic profile is a loading dose of 180 mg followed by 90 mg by mouth twice daily. At these doses, greater platelet inhibition is observed with ticagrelor as compared to clopidogrel 75 mg once daily in both clopidogrel-experienced and -naïve patients. Studies in patients experiencing ACS concluded that ticagrelor reduced the rate of cardiovascular death, nonfatal myocardial infarction, stent thrombosis, and overall mortality compared to clopidogrel without increasing major bleeding when administered with standard therapy for ACS. There was no significant difference in the risk of stroke with ticagrelor compared to clopidogrel; however, intracranial bleeding was more common with ticagrelor. Ticagrelor is well tolerated; however, minor bleeding, dyspnea, hypotension, nausea, and ventricular pauses were reported more frequently than with clopidogrel. Reversible inhibition with ticagrelor may allow for more rapid surgical intervention after discontinuation, suggesting greater flexibility in treatment of ACS.

Conclusions:

Ticagrelor's improved pharmacokinetic and pharmacodynamic profile builds upon the limitations of currently available P2Y12 receptor antagonists. Ticagrelor represents a promising approach for the prevention of cardiovascular events in patients with ACS.

Clinical pharmacology of antithrombotic drugs in coronary artery disease

Coronary heart disease is the leading cause of death in the Western world. Antithrombotic therapy is the cornerstone of its successful treatment. Clinical trials have demonstrated that antithrombotic therapy reduces the risk for recurrent myocardial infarction and cardiovascular death. Antiplatelet drugs and anticoagulants interfere with haemostasis and thus bleeding is a major risk factor of these drugs. The benefit of antithrombotic therapy must therefore be carefully balanced with the risk of bleeding and other potential adverse reactions of these drugs. However, to date there is no firm evidence that dosage adaptation of aspirin or clopidogrel according to platelet aggregation testing translates directly into any clinical benefit. Resistance to antithrombotic drugs is a serious problem because these patients are at a higher risk of myocardial infarction, stroke and cardiovascular death. It has most recently been demonstrated that resistance to clopidogrel is at least in part caused by polymorphism of CYP2C19. Clinical trials have also demonstrated that optimal benefit in different settings depends unequivocally on the meticulous choice of the various drugs. Thus, profound knowledge of the clinical pharmacological profiles of the different antithrombotic drugs is indispensable for successful treatment.