Predictive value of preprocedural fibrinogen concerning coronary stenting

Predictive significance and diagnostic accuracy of plasma fibrinogen levels for coronary stenting outcomes

Objective: The advancement in percutaneous transluminal coronary angioplasty (PTCA) has led to it becoming the predominant mode of revascularization. Post PTCA adverse events in the form of stent thrombosis, recurrent ischemia, unplanned revascularization, recurrent hospitalization etc. result in morbidity as well as mortality. Biomarkers predicting such outcomes can be useful in initiating more aggressive medical therapy and greater modification of risk factors. This study was undertaken to study the predictive significance of periprocedural plasma fibrinogen levels for coronary stenting outcomes. Methods: 80 patients diagnosed as either chronic stable angina (CSA), unstable angina (UA), Non ST Elevation Myocardial Infarction (NSTEMI) or late presentation ST Elevation Myocardial Infarction (STEMI) undergoing planned PTCA were included in study. Patients were evaluated for clinical history, electrocardiogram (ECG), two dimensional echocardiography (2D-echo) and cardiac biomarkers (Creatinine Phorphokinase-MB isomer (CK-MB) and Troponin I). Serum fibrinogen level was measured 24 hours prior to PTCA along with routine pre-operative investigations; and also 24 hours after coronary stenting. Patients were followed for six months. Outcome measure was taken to be freedom from cardiac related adverse events, including rehospitalisation, unplanned repeat revascularization, definite stent thrombosis, transient ischemic attack, stroke and all-cause mortality. Results:  Fibrinogen level ≥393 mg/dL, 24 hours prior to percutaneous transluminal coronary angioplasty, was associated with higher major adverse cardiac and cerebrovascular events (MACCE) rates (60%) as compared to those with fibrinogen level <393 mg/dL (3.6%).  Fibrinogen level ≥427 mg/dL 24 hours after percutaneous transluminal coronary angioplasty, was associated with higher major adverse cardiac and cerebrovascular events rates (65%) as compared to those with fibrinogen level <427 mg/dL (6.7%). Conclusion: The current study demonstrates that higher baseline and post procedural fibrinogen, is an independent predictor of 6 months major adverse cardiac and cerebrovascular events after elective percutaneous coronary intervention. Key words:  Coronary stent outcomes, major adverse cardiac and cerebrovascular events, plasma fibrinogen, stent diameter

The Preoperative Inflammatory Status Affects the Clinical Outcome in Cardiac Surgery

Aims: There are many reasons for the increase in post-operative mortality and morbidity in patients undergoing surgery. In fact, an activated inflammatory state before cardiac surgery, can potentially worsen the patient’s prognosis and the effects of this preoperative inflammatory state in the medium-term remains unknown. Methods: There were 470 consecutive patients who underwent cardiac surgery, and were divided in three groups according to the median values of preoperative C-reactive protein (CRP) and fibrinogen (FBG): The first group was the low inflammatory status group (LIS) with 161 patients (CRP < 0.39 mg/dL and FBG < 366 mg/dL); the second was the medium inflammatory status group (MIS) with 150 patients (CRP < 0.39 mg/dL and FBG ≥ 366 mg/dL or CRP ≥ 0.39 mg/dL and FBG < 366 mg/dL,); and the third was the high inflammatory status group (HIS) with 159 patients (CRP ≥ 0.39 mg/dL and FBG ≥ 366 mg/dL,). Results: The parameters to be considered for the patients before surgery were similar between the three groups except, however, for age, left ventricular ejection fraction (LVEF) and the presence of arterial hypertension. The operative mortality was not significantly different between the groups (LIS = 2.5%, MIS = 6%, HIS = 6.9%, p = 0.16) while mortality for sepsis was significantly different (LIS = 0%, MIS = 1.3%, HIS = 3.7%, p = 0.03). The infections were more frequent in the HIS group (p = 0.0002). The HIS group resulted in an independent risk factor for infections (relative risk (RR) = 3.1, confidence interval (CI) = 1.2–7.9, p = 0.02). During the 48-months follow-up, survival was lower for the HIS patients. This HIS group (RR = 2.39, CI = 1.03–5.53, p = 0.05) and LVEF (RR = 0.96, CI = 0.92–0.99, p = 0.04) resulted in independent risk factors for mortality during the follow-up. Conclusions: The patients undergoing cardiac surgery with a preoperative highly activated inflammatory status are at a higher risk of post-operative infections. Furthermore, during the intermediate follow-up, the preoperative highly activated inflammatory status and LVEF resulted in independent risk factors for mortality.

Periprocedural plasma fibrinogen levels and coronary stent outcome

AIM

Percutaneous intervention is one of the treatment option for coronary artery disease. Reinfarction and restenosis is one of the complication of the procedure. So this study was conducted to assess plasma fibrinogen levels pre- and post coronary stenting and its relation with outcome.

METHODS

After obtaining informed consent, venous blood samples were collected at three timed points in relation to stenting - 24h before, 24h after and 72h after stenting to assess fibrinogen levels. Patients were followed up for six months. Repeat revascularization, myocardial infarction and symptomatic angina were considered as major adverse clinical events.

RESULTS

57 patients who underwent successful stenting and followed up for six months up were included in the study. Mean age was 53 years and 87.7% were males and 29.8% were diabetics. Baseline plasma fibrinogen level was significantly high in patients who developed repeat angina and myocardial infarction after the stenting [288.64±59.43 vs 393.75±32.97mg/dL, p=0.003] and it remained high during serial assessment [322.74±63.92 vs 422.00±55.28mg/dL, 326.23±65.81 vs 419.50±45.82mg/dL, 0.008, 0.012 respectively]. Patients who developed adverse events denied any drug default.

CONCLUSION

We conclude that plasma fibrinogen plays a significant role in the development of adverse events following stenting shown by high level of plasma fibrinogen in patients who developed adverse events.

Plasma fibrinogen levels and restenosis after primary percutaneous coronary intervention

Plasma fibrinogen levels influence restenosis following elective percutaneous coronary intervention (PCI) for stable angina. It is unknown whether the same is true in the setting of primary PCI. The aim of the study was therefore to assess whether fibrinogen levels were associated to 6-month in-stent restenosis (ISR) in STEMI patients undergoing successful primary PCI. From January 2003 to October 2004, 267 patients were admitted to our Institution for STEMI and treated by primary PCI. Of these, 171 patients met the inclusion criteria and were enrolled in our study. Fibrinogen levels were assessed at admission, 12 h, 24 h, 48 h, 72 h following PCI and at discharge. Six-month angiographic follow-up was 100% complete. Subjects with 6-month ISR showed higher fibrinogen levels than patients without ISR. Patients in the upper fibrinogen tertile showed a higher 6-month incidence of symptoms and/or inducible myocardial ischemia (27.1% vs. 7.1%, P = 0.006) and a larger late lumen loss (1.3 ± 0.8 vs. 1.0 ± 0.9 mm, P = 0.049). Logistic regression analysis demonstrated a significant and independent association between fibrinogen levels and ISR. Our study suggests that increased plasma fibrinogen levels are related to ISR in STEMI patients undergoing primary PCI. Larger studies are warranted to assess the prognostic value of fibrinogen over harder end-points.

Inflammation as a marker for the prediction of internal carotid artery restenosis following eversion endarterectomy--evidence from clinical studies

The role of inflammation is well established in the pathogenesis of atherosclerosis and an increased level of circulating inflammatory markers may predict the future risk of atherosclerosis progression and plaque rupture. C-reactive protein (CRP) identification by hypersensitive methods (high-sensitivity CRP [hsCRP]) has become a clinical and laboratory inflammation marker. Carotid endarterectomy (CEA) is a well-established procedure for carotid stenosis treatment which can reduce stroke rate. Internal carotid artery (ICA) restenosis reduction may be prevented by the anti-inflammatory effect of statins. This review considers the recent findings on the presence of hsCRP and C3 complement concentration and inflammatory plaque composition as well as their effects on ICA restenosis rate, following eversion CEA with emphasis on human studies.

The evolving role of inflammatory biomarkers in risk assessment after stent implantation

The main adverse reactions to coronary stents are in-stent restenosis (ISR) and stent thrombosis. Along with procedural factors, individual susceptibility to these events plays an important role. In particular, inflammatory status, as assessed by C-reactive protein levels, predicts the risk of ISR after bare-metal stent implantation, although it does not predict the risk of stent thrombosis. Conversely, C-reactive protein levels fail to predict the risk of ISR after drug-eluting stent (DES) implantation, although they appear to predict the risk of stent thrombosis. Of note, DES have abated ISR rates occurring in the classical 1-year window, but new concern is emerging regarding late restenosis and thrombosis. The pathogenesis of these late events seems to be related to delayed healing and allergic reactions to polymers, a process in which eosinophils seem to play an important role by enhancing restenosis and thrombosis. The identification of high-risk individuals based on biomarker assessment may be important for the management of patients receiving stent implantation. In this report, we review the evolving role of inflammatory biomarkers in predicting the risk of ISR and stent thrombosis.

Relevance of hemostasis on restenosis in clinically stable patients undergoing elective PTCA

BACKGROUND

Secondary coronary thrombus formation is considered to be co-factor in the pathogenesis of restenosis after percutaneous transluminal coronary angioplasty (PTCA). Therefore systemic factors indicating a hypercoagulable disease state may be relevant for the process of coronary renarrowing. Even though experimental data suggest that in particular thrombin may be of major relevance for restenosis induced by mechanical injury, only little clinical data has been presented so far.

METHODS AND RESULTS

In 60 consecutive patients, who had been clinical stable for at least 2 months, and who underwent elective and primarily successful PTCA, follow-up films were evaluated by means of quantitative coronary angiography in respect to a categorical and a continuous definition of restenosis, luminal narrowing >50% and late luminal loss respectively. Of the chosen laboratory variables prothrombin fragment 1+2 (1.3+/-0.5 vs. 0.9+/-0.4 mmol/l, p<0.001) red blood cell aggregation at low shear stress (13.5+/-2.9 vs. 11.6+/-2.8 units, p<0.05), and plasminogen-activator inhibitor (3.7+/-1.8 vs. 5.3+/-3.2 U/ml p<0.05) differentiated between patients with (n=18) and without restenosis (n=42). Late luminal loss correlated positively with prothrombin fragment 1+2 (r=0.41, p<0.001), plasminogen-activator inhibitor (r= -0.28, p<0.05) and plasmin-alpha2-antiplasmin complex (r=0.39, p<0.01).

CONCLUSIONS

A hypercoagulable disease state and in particular thrombin generation characterize a high-risk group prone for restenosis in clinically stable coronary artery disease.

Present status of outcome prediction of invasive coronary treatment by using genetic markers

A growing number of studies suggest that the outcome after invasive coronary treatment may be in part genetically determined. Here, we review the present status of outcome prediction of invasive coronary treatments by using genetic markers. Although some studies found an association between one or another genetic marker with one or another clinical endpoint, many other studies found no such relations; to date, none of the genetic markers that have been investigated in association studies are used in routine clinical practice to prospectively assess the prognosis following invasive coronary treatment or to decide upon therapeutic strategies. Many associations between genetic markers and certain clinical endpoints were initially reported in small studies but could not be confirmed in larger ones. Some of these discrepancies may be explained by publication bias. Some genetic variants may have true effects on clinical endpoints, which, albeit biologically interesting, do not bear much clinical relevance. On the other hand, many-if not most-studies that have been published to date are more or less grossly underpowered and very rarely report on the results of an a priori power analysis. Thus, there is still a need for further high-quality studies designed to investigate the specific contribution of genetic factors to the outcome after invasive coronary interventions.

Homocysteine Levels, Haemostatic Risk Factors and Patency Rates After Endovascular Treatment of the Common Iliac Arteries

OBJECTIVES

To investigate the impact of clinical risk factors, plasma homocysteine and haemostatic variables on the results after endovascular treatment of symptomatic atherosclerosis of the common iliac artery.

DESIGN

Prospective observational study.

SETTING

University hospital.

PATIENTS AND METHOD

The study included 139 technically successful interventions in 103 patients. Technical success was defined as < or = 30% residual stenosis as seen on the post treatment angiogram. Blood samples for analyses of fasting plasma values of homocysteine, fibrinogen, D-dimer, activated protein C resistance were drawn upon admission. Median follow-up for all procedures was 22 months (range 0-55 months). Patency was defined as freedom from > or = 50% restenosis or reocclusion.

RESULTS

The technical success rate for all procedures was 93%. The 1-year cumulative primary patency rate based on intention to treat was 85%. Multivariate analysis revealed a significant independent association between patency rates and levels of fibrinogen and homocysteine and the nature of the lesion treated (stenosis vs. occlusion).

CONCLUSION

The aetiology of restenoses and reocclusions is probably multifactorial. Procoagulant activity, the nature of the lesion treated and homocysteine levels within and above the upper range of normal limits are important risk factors for failure after endovascular treatment of the common iliac arteries.

A Model System to Assess Key Vascular Responses to Biomaterials

PURPOSE

To establish a reproducible laboratory test to evaluate prospective vascular biomaterials with respect to their thromboinflammatory properties by examining fibrinogen, platelet, and monocyte binding. Endothelial migration onto these surfaces was used as an index of vascular healing.

METHODS

To evaluate biomaterials for potential thrombogenicity and inflammation, binding assays of radiolabeled human fibrinogen, platelets, and monocytes were performed on standard pieces of vascular biomaterials, including metals and polymeric and ceramic-coated materials. Using an established in vitro endothelial cell migration model, the relative migration rate of cultured human aortic endothelial cells onto these vascular biomaterials was measured and compared. The fibrinogen, platelet, and monocyte binding results were combined along with the migration results to create an overall score of biocompatibility.

RESULTS

A significant direct relation of platelet and monocyte binding to the amount of adsorbed fibrinogen was observed. In contrast, migration rates of cultured human aortic endothelial cells onto the same biomaterial surfaces were found to be inversely related the amount of bound fibrinogen. Among the materials tested, stainless steel received the highest score of biocompatibility, while turbostratic carbon scored the lowest.

CONCLUSIONS

Fibrinogen, platelet, and monocyte binding levels, as well as endothelial migration rates onto vascular material surfaces, provide a basis for evaluating thrombogenicity, inflammatory potential, and endothelialization in the laboratory prior to in vivo testing.

Impact of baseline renal function on mortality after percutaneous coronary intervention with sirolimus-eluting stents or bare metal stents

Renal impairment is an important predictor of mortality after percutaneous coronary intervention and may increase the restenosis rate. However, the relation between restenosis and the risk of death in patients who have renal impairment remains unclear. We evaluated the incidences of repeat revascularization and mortality in patients who had renal impairment and those who did not and who received sirolimus-eluting stents or bare stents. A total of 1,080 consecutive patients treated for 1 year had available data to calculate baseline creatinine clearance. Patients received bare stents (first 6 months, n = 543) or sirolimus-eluting stents (last 6 months, n = 537) and were grouped according to the presence or absence of renal impairment (creatinine clearance <60 ml/min). Patients who had renal impairment had a higher mortality rate at 1 year (7.6% vs 2.5%, hazard ratio 3.14, 95% confidence interval 1.68 to 5.88, p <0.01), with no differences in mortality between patients who received bare stents and those who received sirolimus-eluting stents (hazard ratio 0.91, 95% confidence interval 0.49 to 1.68, p = 0.8). The incidence of target vessel revascularization decreased significantly in patients who were treated with sirolimus-eluting stents and did not have renal impairment (hazard ratio 0.59, 95% confidence interval 0.39 to 0.90, p = 0.01) and in those who had decreased renal function (hazard ratio 0.37, 95% confidence interval 0.15 to 0.90, p = 0.03). Thus, sirolimus-eluting stents compared with conventional stents decreased clinical restenosis in patients who had renal impairment. However, this benefit was not paralleled by a decrease in the risk of death in this population. It seems unlikely that restenosis could be a contributing factor that influenced the increased mortality of patients who had impaired renal function.