Perioperative changes of response to antiplatelet medication in vascular surgery patients.

Introduction: Reduced antiplatelet activity of aspirin (ALR) or clopidogrel (CLR) is associated with an increased risk of thromboembolic events. The reported prevalence data for low-responders vary widely and there have been few investigations in vascular surgery patients even though they are at high risk for thromb-embolic complications. The aim of this prospective observational monocentric study was to elucidate possible changes in ALR or CLR after common vascular procedures.

Comparison of perioperative strategies in ICD patients: The perioperative ICD management study (PIM study).

Background: The prevalence of patients with implanted cardioverter defibrillators (ICDs) and the frequency of surgery on these patients are steadily on the rise. Guidelines recommend preoperative ICD reprogramming, although this is sometimes difficult in clinical practice. Placing a magnet on the ICD is a practical alternative and even no inactivation is possible in selected cases.

Cortisol, platelet serotonin content, and platelet activity in patients with major depression and type 2 diabetes: an exploratory investigation.

Objective: Hypothalamic-pituitary-adrenal system dysfunction, serotonergic system alterations, and enhanced platelet activity may contribute to the increased cardiac risk in depression. This exploratory study examined associations between cortisol parameters, platelet serotonin (5-HT) content, and platelet activity markers in patients with newly diagnosed major depression (MD) and/or Type 2 diabetes (T2DM) compared with healthy controls.

Methods: We compared cortisol awakening response (CAR), diurnal decrease in salivary cortisol concentrations (slope), platelet 5-HT, and platelet markers (CD40, CD40 ligand [CD40L], soluble CD40L, CD62P, β-thromboglobulin, and platelet factor-4) in 22 T2DM patients, 20 MD patients, 18 T2DM patients with MD, and 24 healthy controls.

Safety and effectiveness of a novel vascular closure device: a prospective study of the ExoSeal compared to the Angio-Seal and ProGlide.

Purpose: To prospectively assess the safety and efficacy of a novel absorbable vascular closure device (ExoSeal) in patients undergoing cardiac catheterization with femoral access compared to the established collagen-based (Angio-Seal) and suture-mediated (ProGlide) closure devices.

Methods: This prospective, observational, dual-center, non-randomized, non-blinded study enrolled 1013 patients (65.1 ± 11.

Monitoring ASA and P2Y12-specific platelet inhibition--comparison of conventional (single) and multiple electrode aggregometry.

Objective: Several platelet function test systems exist for the evaluation of the platelet inhibitory effect in patients on P2Y12 inhibitors and/or acetylsalicylic acid (ASA, aspirin) therapy. Studies comparing different available assays found only a poor correlation. The objective of the present study was to evaluate the correlation and agreement between single electrode (SEA) and multiple electrode (MEA) aggregometry.

Clopidogrel high-on-treatment platelet reactivity in acute ischemic stroke patients.

Background: During the first days following an acute ischemic stroke, a consistently good antiplatelet effect of clopidogrel is important due to the increased risk of recurrent ischemia. However, the platelet inhibitory effectiveness of clopidogrel is variable for multifactorial reasons. We investigated the prevalence and risk factors for clopidogrel high-on-treatment platelet reactivity (clopidogrel-HTPR) in acute ischemic stroke patients.

Cytochrome P450 2B6 and 2C9 genotype polymorphism--a possible cause of prasugrel low responsiveness.

The cytochrome P450 (CYP) isoenzymes are essential for the metabolic activation of the prodrug prasugrel. Little is known about the impact of polymorphism of these isoenzymes on the prevalence of prasugrel low responsiveness (PLR) in patients with coronary artery disease. We investigated the frequency of PLR and the question whether PLR is associated with decreased/non-function polymorphisms of the CYP isoenzymes (2C9*2, 2C9*3, 2C19*2, 2C19*3, and 2B6*6).

Newly diagnosed depression is associated with increased beta-thromboglobulin levels and increased expression of platelet activation markers and platelet derived CD40-CD40L.

Background: Inflammation plays a key role in atherosclerotic disease. Up until now only limited evidence exists on the mechanism of cardiovascular complications in patients with depression. In addition depression was also linked to an increase in cardiovascular mortality.

Effectiveness of antiplatelet therapy in atherosclerotic disease: comparing the ASA low-response prevalence in CVD, CAD and PAD.

Although acetylsalicylic acid (ASA, aspirin) reduces the risk of ischemic events in patients with atherosclerosis, a substantial number of incidents continue to occur. As only limited data exist we evaluated the antiplatelet effectiveness of ASA in patients with different manifestations of atherosclerosis as in cerebrovascular, coronary artery and peripheral arterial disease (CVD, CAD, PAD). For the evaluation of the antiplatelet effectiveness of ASA we used whole blood aggregometry (Chrono-log Model 590).

Ventricular tachycardia during basilar-type migraine attack.

Autonomic dysfunction is a characteristic of migraine attacks, rarely, even cardiac repolarization abnormalities have been associated with migraine. We report a case of documented ventricular tachycardia during basilar-type migraine attack. The therapeutic implications of such a co-occurrence as well as a possible relationship between ventricular tachycardia and the underlying biology of basilar-type migraine are discussed.

New pathways of increased cardiovascular risk in depression: a pilot study on the association of high-sensitivity C-reactive protein with pro-atherosclerotic markers in patients with depression.

Background: An elevation of inflammatory markers such as high-sensitivity C-reactive protein (hs-CRP) can be found in patients with depressive disorders. Inflammatory processes are known to influence atherosclerosis and might also mediate the link between depression and diabetes. The present study aimed at comparing hs-CRP and its relationship with atherogenic platelet markers in patients with type 2 diabetes (TD2) and/or newly diagnosed major depression (MD).

Dose-dependent effect of early antiplatelet therapy in acute ischaemic stroke.

Antiplatelet agents are essential in treating patients with acute ischaemic stroke (AIS) to prevent recurrent ischaemic events. The aim of this study was to evaluate the effectiveness of early antiplatelet therapy with different aspirin (ASA) dosages in patients with AIS. This observational study included 454 patients with AIS in whom antiplatelet treatment was initiated.

Which is the best anticoagulant for whole blood aggregometry platelet function testing? Comparison of six anticoagulants and diverse storage conditions.

Major hindrances of impedance aggregometry are caused by limited storage time and the requirement of ex vivo anticoagulation. Data on the influence of different anticoagulants and storage conditions are rare and incomplete. This study has systematically examined the influence of six different anticoagulants (sodium and lithium heparin, 20 µg/mL and 45 µg/mL r-hirudin, benzylsulfonyl-D-Arg-Pro-4-amidinobenzylamide (BAPA), and citrate) on the results of Adenosine 5'-diphosphate (ADP) and arachidonic acid (AA) induced measurements using multiple-electrode impedance aggregometer (MEA).

Is there an ideal way to initiate antiplatelet therapy with aspirin? A crossover study on healthy volunteers evaluating different dosing schemes with whole blood aggregometry.

Background: Guidelines recommend an early initiation of aspirin treatment in patients with acute cerebral ischemia. Comparative studies on the best starting dose for initiating aspirin therapy to achieve a rapid antiplatelet effect do not exist. This study evaluated the platelet inhibitory effect in healthy volunteers by using three different aspirin loading doses to gain a model for initiating antiplatelet treatment in acute strokes patients.

BAPA, a synthetic dual inhibitor of Factor Xa and Thrombin, extends the storage-time to a maximum of 12 hours in ADP- and 24 hours in arachidonic acid-induced impedance aggregometry.

Impedance aggregometry is mainly limited by the time-dependent instability of platelets in whole blood samples, caused by the influence of ex-vivo anticoagulants. The synthesis of a new anticoagulant, Benzylsulfonyl-D-Arg-Pro-4-amidinobenzylamide (BAPA), has recently been introduced. Data from recent studies suggest stable results for up to 32 h.

Tailored antiplatelet therapy can overcome clopidogrel and aspirin resistance--the BOchum CLopidogrel and Aspirin Plan (BOCLA-Plan) to improve antiplatelet therapy.

Background: Dual antiplatelet therapy using acetylsalicylic acid (ASA, aspirin) and clopidogrel is of great importance following coronary stenting. However, the variable platelet inhibitory effectiveness compromises the antithrombotic advantages provided by dual antiplatelet therapy. The aim of this single-center prospective study was to reduce the low response incidence of dual antiplatelet therapy with ASA and clopidogrel according to a prespecified therapy algorithm.

Pantoprazole does not influence the antiplatelet effect of clopidogrel-a whole blood aggregometry study after coronary stenting.

Recent attention has been drawn to a potential drug-drug interaction observed between clopidogrel and proton pump inhibitors (PPIs). However, this potential interaction may not be a class effect of PPIs. We investigated if pantoprazole, which has a different metabolism than omeprazole, diminishes the effectiveness of clopidogrel.

Unrecognized secondary causes of hypertension in patients with hypertensive urgency/emergency: prevalence and co-prevalence.

Background: Hypertensive urgency/emergency occurs frequently, yet no prospective data on common secondary causes, including sleep apnea (SA), renal artery stenosis (RAS), and hyperaldosteronism, are available.

Methods: Patients presenting to the emergency room for over 1 year with systolic blood pressure > or =180 mmHg and/or diastolic blood pressure > or =100 mmHg and typical symptoms were included. RAS was diagnosed by direct duplex/Doppler ultrasound of the renal artery, resistance index, and imaging.

Upregulation of platelet CD40, CD40 ligand (CD40L) and P-Selectin expression in cigarette smokers: a flow cytometry study.

Cigarette smoking is a well known risk factor for cardiovascular disease with a great impact on mortality. Studies have linked smoking to inflammation, platelet activation and enhanced atherosclerosis. The present study investigated the activation and expression of proinflammatory markers on platelets obtained from smokers.

Comparing the antiplatelet effect of clopidogrel hydrogensulfate and clopidogrel besylate: a crossover study.

Background: Clopidogrel hydrogensulfate is a thienopyridine acting as an important antiplatelet agent alone or in combination with acetyl salicylic acid to prevent cardiovascular complications. A different clopidogrel salt, clopidogrel besylate, was approved in Germany as a "new drug" in May 2008. Only one study with 46 healthy men compared the plasma concentrations of both clopidogrel formulas.

The CYP2J2 G-50T polymorphism and myocardial infarction in patients with cardiovascular risk profile.

Background: Cytochrome P450 (CYP) enzyme 2J2, an epoxygenase predominantly expressed in the heart, metabolizes arachidonic acid to biologically active eicosanoids. One of the CYP2J2 products, 11, 12-epoxyeicosatrienoic acid, has several vasoprotective effects. The CYP2J2-G-50T-promotor polymorphism decreases gene expression and is associated with coronary artery disease.