ClotCare: Blood Clots, Stroke, Heart Attack
Sunday, October 13, 2024
Home   |   DVT/PE   |   Blood Clots   |   Coumadin/Warfarin   |   New Patients   |   Self Testing   |   Email List   |   Donate

Pick a Topic:

Find info on a:

We subscribe to the HONcode principles of the HON Foundation. Click to verify.
ClotCare complies with the HONcode standard for trustworthy health
information:
verify here.

ClotCare is a member of the Coalition to Prevent Deep Vein Thrombosis (DVT Coalition)  ClotCare is a member organization of the Coalition to Prevent Deep Vein Thrombosis. Click here to learn more about the Coalition to Prevent Deep Vein Thrombosis and DVT Awareness Month, which is held each March.

Emerging data in VTE Prevention for Acutely Ill Medical Patients

Edith A. Nutescu, Pharm.D.
September 2004

The recently published PREVENT study (Prospective Evaluation of Dalteparin efficacy for Prevention of venous thrombosis (VTE) in Immobilized Patients Trial) examined the efficacy and safety of dalteparin (a low-molecular-weight heparin) in the prevention of clinically important venous thromboembolic events in medical patients. A total of 3706 patients were randomized to receive either dalteparin (5000IU SC QD) or placebo for 14 days and followed for 90 days. The primary end point was venous thromboembolism detected by compression ultrasound at day 21 and sudden death by day 21. The incidence of venous thromboembolism was significantly lower in the dalteparin group as compared to the placebo group. (2.77% versus 4.96% respectively; p = 0.0015; 45%RRR and 2.19 ARR) This observed benefit in favor of dalteparin was maintained at 90 days. Major bleeding was slightly higher in the dalteparin group versus placebo but not statistically significant. (0.49% versus 0.19% respectively; p = 0.15)

The PREVENT study provides additional information to the existing body of evidence, supporting the use of low-molecular-weight heparin (LMWH) for VTE prevention in medical patients. Two previous studies have compared enoxaparin (a LMWH) and fondaparinux (a synthetic factor-Xa inhibitor) to placebo.1,3 (See Table) These prior studies have demonstrated a reduction in asymptomatic VTE , driven largely by distal deep vein thrombosis (DVT) detected by venography. As the clinical relevance of distal asymptomatic DVT is controversial and symptomatic DVT or asymptomatic proximal DVT are accepted as clinically relevant, the PREVENT study differs from the MEDENOX and ARTEMIS studies in that compression ultrasound was used to assess efficacy. Compared to MEDENOX, patients enrolled in PREVENT were at lower risk of VTE, therefore further extending the appropriateness and applicability of thromboprophylaxis in a broader patient population than previously documented.

Major Placebo Controlled Studies for VTE Prevention in Medical Patients

  MEDENOX (1) PREVENT (2) ARTEMIS (3)
Study Population - Age ≥ 40 yrs, expected hospital stay ≥ 6 days

and
- CHF (NYHA III/IV)
- acute respiratory illness
- infection or bone/joint or inflamed bowel

plus 1 risk factor
- Age ≥ 40 yrs, expected hospital stay ≥ 6 days

and
- CHF (NYHA III/IV)
- acute respiratory failure
- acute severe systemic disease

plus 1 risk factor
- Age ≥ 60 yrs, expected hospital stay ≥ 4 days

and
- CHF (NYHA III/IV)
- acute or chronic lung disease
- acute infectious or inflammatory disease

no other risk factor required
Primary Efficacy Endpoint Efficacy
- distal & proximal venographic DVT
+ symptomatic VTE
+ fatal PE
Efficacy
- ultrasonographic proximal DVT
+ symptomatic VTE
+ fatal PE
Efficacy
- distal & proximal venographic DVT
+ symptomatic VTE
+ fatal PE
Proximal DVT + Symptomatic VTE at D14-21 Enoxaparin: 2.1%
Placebo: 6.6%
P = 0.037
Dalteparin: 2.7%
Placebo: 5.0%
P = 0.002
Fondaparinux: 1.5%
Placebo: 3.4%
P = 0.085
Major Bleeding Enoxaparin: 1.7%
Placebo: 1.1%
ns
Dalteparin: 0.5%
Placebo: 0.2%
ns
Fondaparinux: 0.2%
Placebo: 0.2%
ns

References

1. Samama MM, Cohen AT, Darmon JY, et.al. A comparison of enoxaparin with placebo for the prevention of venous thromboembolism in acutely ill medical patients. N Engl J Med 1999;341:793-800.

2. Leizorovicz A, Cohen AT, Turpie AG, et.al. Randomized, Placebo-Controlled Trial of Dalteparin for the Prevention of Venous Thromboembolism in Acutelly Ill Medical Patients. Circulation 2004;110:874-879.

3. Cohen AT, Davidson BL, Gallus AS, et.al. Fondaparinux for the prevention of VTE in acutely ill medical patients. Blood 2003;102:42. [abstract].

Ask a question about blood clots or anticoagulant medications Have questions? Ask ClotCare. Send questions by email to webmaster@clotcare.org.

ClotCare is a 501(c)(3) non-profit organization generously supported by your tax-deductible donations and grants from our industry supporters.

Blood Clot Activities Calendar

New Postings:

Click here to view full list of new postings
ClotCare Home | New Postings | Patient Postings | Clinician Postings | Join Our Email List | Useful Web Links
CE Opportunities | Training Programs | DVT & PE Stories | Editorial Board | Financial Support
About ClotCare | DVT Coalition | Donate to ClotCare | Contact Us
Key topics discussed on ClotCare include: Blood Clots | Deep Vein Thrombosis (DVT) | Pulmonary Embolism (PE) | Atrial Fibrillation (A. Fib or AF) | Heart Attack | Stroke | Transient Ischemic Attack (TIA) | Mini Stroke | Bleeding Complications | Vascular Surgery | Surgical Blood Clot Removal | Warfarin | Coumadin | Lovenox | Low Molecular Weight Heparin (LMWH) | Heparin | Anticoagulants | Plavix | Aspirin | Antiplatelets | Blood Thinners
Copyright 2000-2018 by ClotCare. All rights reserved.
Terms, Conditions, & Privacy | Image Copyright Information
19260 Stone Oak Parkway, Suite 101 | San Antonio, TX 78258 | 210-860-0487
Send comments to webmaster@clotcare.org.
Sunday, October 13, 2024