Oral anticoagulant therapy during and after coronary angioplasty the intensity and duration of anticoagulation are essential to reduce thrombotic complications

Comparison of additional versus no additional heparin during therapeutic oral anticoagulation in patients undergoing percutaneous coronary intervention

Uninterrupted oral anticoagulation (OAC) therapy can be the preferred strategy in patients with atrial fibrillation at moderate to high risk of thromboembolism undergoing percutaneous coronary intervention (PCI). To evaluate the need for additional heparins in addition to therapeutic peri-PCI OAC, we assessed bleeding complications and major adverse cardiac and cerebrovascular events in 414 consecutive patients undergoing PCI during therapeutic (international normalized ratio 2 to 3.5) periprocedural OAC. Patients were divided into those with no (n = 196) and with (n = 218) additional use of periprocedural heparins. No differences in major adverse cardiac and cerebrovascular events (4.1% vs 3.2%, p = 0.79) or major bleeding (1.0% vs 3.7%, p = 0.11) were detected, but access site complications (5.1% vs 11.0%, p = 0.032) were less frequent in those without additional heparins. When adjusted for propensity score, patients with additional heparins had a higher risk of access site complications (odds ratio 2.6, 95% confidence interval 1.1 to 6.1, p = 0.022) without any increased risk of any other adverse event. Analysis of 1-to-1 propensity-matched pairs showed a significantly higher risk of access site complication in patients receiving additional AC (13.1% vs 5.7%, p = 0.049). In conclusion, therapeutic warfarin treatment seems to provide sufficient AC for PCI. Additional heparins are not needed and may increase access site complications.

'Ins' and 'outs' of triple therapy: Optimal antiplatelet therapy in patients on chronic oral anticoagulation who need coronary stenting

Chronic oral anticoagulant treatment is obligatory in patients (class I) with mechanical heart valves and in patients with atrial fibrillation with CHADS2 score >1. When these patients undergo percutaneous coronary intervention with placement of a stent, there is also an indication for treatment with aspirin and clopidogrel. Unfortunately, triple therapy is known to increase the bleeding risk. For this group of patients, the bottom line is to find the ideal therapy in patients with indications for both chronic anticoagulation therapy and percutaneous intervention to prevent thromboembolic complications such as stent thrombosis without increasing the risk of bleeding. (Neth Heart J 2010;18:444-50.).

Antithrombotic management of atrial fibrillation patients presenting with acute coronary syndrome and/or undergoing coronary stenting: executive summary--a Consensus Document of the European Society of Cardiology Working Group on Thrombosis, endorsed by the European Heart Rhythm Association (EHRA) and the European Association of Percutaneous Cardiovascular Interventions (EAPCI)

There remains uncertainty over optimal antithrombotic management strategy for patients with atrial fibrillation (AF) presenting with an acute coronary syndrome and/or undergoing percutaneous coronary intervention/stenting. Clinicians need to balance the risk of stroke and thromboembolism against the risk of recurrent cardiac ischaemia and/or stent thrombosis and the risk of bleeding. The full consensus document comprehensively reviews the published evidence and presents a consensus statement on a 'best practice' antithrombotic therapy guideline for the management of antithrombotic therapy in such AF patients. This executive summary highlights the main recommendations from the consensus document.

Design and rationale of the WOEST trial: What is the Optimal antiplatElet and anticoagulant therapy in patients with oral anticoagulation and coronary StenTing (WOEST)

BACKGROUND

Long-term oral anticoagulant treatment is obligatory in patients (class I) with mechanical heart valves and most patients with atrial fibrillation. When these patients undergo percutaneous coronary intervention with stenting, there is also an indication for treatment with aspirin and clopidogrel. However, triple therapy is known to increase the risk of bleeding complications. Unfortunately, there are no prospective data available to resolve this issue. Nevertheless, it all comes down to finding the ideal therapy in patients with indications of both chronic anticoagulation therapy and percutaneous intervention to prevent thrombotic complications (eg, stent thrombosis) without increasing the risk of bleeding.

OBJECTIVES

This prospective randomized multicenter study will assess the hypothesis that after percutaneous coronary intervention with stent implantation in patients on oral anticoagulant therapy, the combination of oral anticoagulation therapy and clopidogrel 75 mg/d reduces the risk of bleeding and is not inferior to triple therapy treatment with respect to the prevention of thrombotic complications.

DESIGN

Multicenter, international, open-label randomized trial evaluating triple therapy (clopidogrel + oral anticoagulants + aspirin) in patients with an indication for oral anticoagulants who undergo coronary stenting versus the combination of oral anticoagulants and clopidogrel. The primary outcome is the combination of TIMI and GUSTO minor and major bleeding up to 30 days and 1 year. The secondary outcomes are major adverse cardiac events. The sample size is 496.

CONCLUSIONS

No prospective randomized study has yet addressed the issue of optimal antiplatelet therapy in patients with chronic oral anticoagulant therapy undergoing coronary stenting. Therefore, the WOEST trial will help to define new guidelines for patients with indication for chronic anticoagulation who need coronary stenting.

Anticoagulation intensity and outcomes among patients prescribed oral anticoagulant therapy: a systematic review and meta-analysis

BACKGROUND

Patients taking oral anticoagulant therapy balance the risks of hemorrhage and thromboembolism. We sought to determine the association between anticoagulation intensity and the risk of hemorrhagic and thromboembolic events. We also sought to determine how under-or overanticoagulation would influence patient outcomes.

METHODS

We reviewed the MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and CINAHL databases to identify studies involving patients taking anticoagulants that reported person-years of observation and the number of hemorrhages or thromboemboli in 3 or more discrete ranges of international normalized ratios. We estimated the overall relative and absolute risks of events specific to anticoagulation intensity.

RESULTS

We included 19 studies. The risk of hemorrhage increased significantly at high international normalized ratios. Compared with the therapeutic ratio of 2-3, the relative risk (RR) of hemorrhage (and 95% confidence intervals [CIs]) were 2.7 (1.8-3.9; p < 0.01) at a ratio of 3-5 and 21.8 (12.1-39.4; p < 0.01) at a ratio greater than 5. The risk of thromboemboli increased significantly at ratios less than 2, with a relative risk of 3.5 (95% CI 2.8-4.4; p < 0.01). The risk of hemorrhagic or thromboembolic events was lower at ratios of 3-5 (RR 1.8, 95% CI 1.2-2.6) than at ratios of less than 2 (RR 2.4, 95% CI 1.9-3.1; p = 0.10). We found that a ratio of 2-3 had the lowest absolute risk (AR) of events (AR 4.3%/yr, 95% CI 3.0%-6.3%).

CONCLUSIONS

The risks of hemorrhage and thromboemboli are minimized at international normalized ratios of 2-3. Ratios that are moderately higher than this therapeutic range appear safe and more effective than subtherapeutic ratios.

Effectiveness of manual pressure hemostasis following transfemoral coronary angiography in patients on therapeutic warfarin anticoagulation

We evaluated the effectiveness of manual pressure hemostasis after transfemoral coronary angiography in patients on therapeutic warfarin anticoagulation (international normalized ratio [INR] 2.0 to 3.0) compared with discontinuing warfarin > or =48 hours before the procedure (INR <2.0). There was a low incidence of small hematomas with either strategy (no significant difference) and no major vascular complications. No prolonged hospital stay due to an access site complication was observed, and no thromboembolic events occurred. In conclusion, transfemoral coronary angiography appears to be safe in patients on warfarin with an INR of 2.0 to 3.0).

Cognitive Impairment as Determinant for Sub-Optimal Control of Oral Anticoagulation Treatment in Elderly Patients with Atrial Fibrillation

BACKGROUND AND OBJECTIVE

Atrial fibrillation is an indication for oral anticoagulation treatment. Maintaining the International Normalized Ratio (INR) within the therapeutic range minimises thromboembolic and bleeding complications. We have investigated whether cognitive capacity affects control of anticoagulation in elderly patients with atrial fibrillation.

PATIENTS AND METHODS

A retrospective study was conducted to investigate the association between cognitive impairment and control of anticoagulation. Patients > or =70 years of age with atrial fibrillation using acenocoumarol (nicoumalone) as anticoagulant were included. All patients were monitored by the Anticoagulation Clinic in the Midden-Brabant region in the Netherlands. The cognitive function of all patients was assessed using the Mini-Mental State Examination (MMSE) on the index date. INR values were obtained from the year preceding the index date. Patients with an MMSE score <23 were defined as cognitively impaired. The primary outcome of the study was the incidence of an INR value within the therapeutic range of 2.0-3.4 during < or =70% of treatment time in the year prior to the cognitive function assessment. The secondary endpoint was the number of patients with an INR <2.0 or > or =6.0 at least once during this year. Logistic regression analysis was used to evaluate the association between cognitive function and control of anticoagulation.

RESULTS

A total of 152 patients were included in the study. An MMSE score <23 was associated with an inadequate INR control (odds ratio [OR] 2.77; 95% CI 1.13, 6.74). After correction for hospital admission and change of possibly interacting medication (both also associated with inadequate INR control), this association remained statistically significant. Significantly more patients with an MMSE score <23 had one or more INR values of six or higher (OR 3.06; 95% CI 1.14, 8.18).

CONCLUSION

In elderly people with atrial fibrillation using oral anticoagulation, an MMSE score <23 is independently associated with an inadequate INR control, mainly because of an increased number of supratherapeutic INR values. This finding should be taken into account when making decisions about use of oral anticoagulants in the elderly.

What is the role for improved long-term antiplatelet therapy after percutaneous coronary intervention?

BACKGROUND

Coronary stent placement has replaced balloon angioplasty as the percutaneous coronary intervention (PCI) method of choice, primarily because of its lower restenosis rate. Compared with aspirin (ASA) monotherapy or ASA plus warfarin, the ticlopidine and ASA combination is superior in reducing thrombotic events after stenting. Clopidogrel plus ASA appears to be at least as effective as ticlopidine and ASA. Intravenous glycoprotein IIb/IIIa inhibitors effectively prevent periprocedural thrombotic complications, but their short duration of action and parenteral dosing don't allow for long-term protection. This review aimed to answer how long after PCI with a stent patients are at risk for recurrent thrombotic events and what the optimal way to prevent them is.

RESULTS

Classically, ASA has been prescribed indefinitely, whereas adenosine diphosphate receptor antagonists have been discontinued after 2 to 4 weeks. However, the Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE) trial found that long-term dual antiplatelet therapy with clopidogrel and ASA was more effective than ASA alone in preventing major cardiovascular events in patients with acute coronary syndrome, including those treated with PCI.

CONCLUSION

Results from additional ongoing studies are needed to clarify the role of long-term dual oral antiplatelet therapy in preventing ischemic events in patients who have undergone PCI.

Warfarin for ischemic heart disease

Oral anticoagulation is one of the oldest ways for preventing secondary ischemic heart disease. With the introduction of aspirin, and low-dose aspirin in particular, the interest in oral anticoagulants has diminished, given the inherent bleeding risk. This short review deals with the efficacy and safety of oral anticoagulation in treating ischemic heart disease compared to placebo and to low-dose aspirin. Also, the comparison of the combination of oral anticoagulants and aspirin to aspirin alone is made. After myocardial infarction, oral anticoagulation is far superior to placebo in preventing recurrent ischemic events, with a risk of major bleeding of 1 per 100 patient-years. Oral anticoagulation seems equivalent to aspirin after myocardial infarction, but shows the same excess bleeding. Clearly, aspirin is, therefore, preferable for this indication. Combination therapy with oral anticoagulants and aspirin seems superior to aspirin alone provided the international normalized ratio is kept over 2.0. Also, here bleeding occurs in 1 out of 100 patient-years and the risk must be weighed against the risk of recurrent ischemic events. In coronary angioplasty, warfarin given before intervention looks promising in one large trial, but when given after intervention it is not beneficial and leads to more bleeding. Long-term oral anticoagulation does not lead to better graft patency after coronary surgery, but in one large trial it did lead to a better rate of survival.