Low molecular weight heparin bridging for atrial fibrillation: is VTE thromboprophylaxis the major benefit?
Paucity of data has led to a lack of consensus regarding indications for, and risk-benefit ratio of, low molecular weight heparin 'bridging' for cardioembolic prevention in patients with atrial fibrillation (AF) until their INR levels are in therapeutic range. Using a hospital database, we compared AF patients ≥65 years who were bridged (n = 265) with patients who were not bridged (n = 4532) after hospital discharge. Patients who failed to achieve a therapeutic INR within 30 days were excluded. CHADS₂ scores (congestive heart failure, hypertension, age ≥75, diabetes, stroke), bleeding risk and co-morbidity scores were assessed. Unadjusted and adjusted odds ratios for outcome events (death, stroke, hemorrhage and venous thromboembolism (VTE) within 30 days of discharge were compared. Bridged patients, as compared to those not bridged, were younger (74.7 ± 6.6 vs. 78.5 ± 7.7 years), less likely to be white (36 vs. 51%), and less likely to have CHADS₂ scores ≥2 (67 vs. 84%), all P < 0.001. There was no significant difference in bleeding risk (bridged vs. not bridged: 1.5 ± 7 vs. 1.7 ± 6). In logistic models adjusting for age, white race, bleeding risk, CHADS₂ and Comorbidity scores, bridging was significantly associated with lower mortality and a decreased odds ratio for VTE (both P < 0.01) but not for stroke or hemorrhage (both P > 0.80). Although we found insufficient evidence of either lower stroke or greater bleeding risk with bridging, our data suggest the possibility that LMWH bridging in patients with AF is associated with lower risks of VTE and death within 30 days of discharge.
Billett
Henny H
HH
Division of Hematology, Montefiore Medical Center, Albert Einstein College of Medicine, 3411 Wayne Ave., Bronx, NY 10467, USA. henny.billett@einstein.yu.edu
Scorziello
Barbara A
BA
Giannattasio
Emily R
ER
Cohen
Hillel W
HW
D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000150:complications / Q000188:drug therapy*; D015331:Cohort Studies; D016208:Databases, Factual; D005260:Female; D006495:Heparin, Low-Molecular-Weight / Q000008:administration & dosage*; D006801:Humans; D019934:International Normalized Ratio / Q000379:methods; D008297:Male; D012307:Risk Factors; D054556:Venous Thromboembolism / Q000209:etiology / Q000517:prevention & control*
D006495:Heparin, Low-Molecular-Weight
Am J Med. 1998 Aug;105(2):91-9
9727814
J Thromb Haemost. 2005 Dec;3(12):2823-5
16359528
Circulation. 2004 Sep 21;110(12):1658-63
15364803
Med Klin (Munich). 2007 Oct 15;102(10):809-15
17928964
Crit Pathw Cardiol. 2003 Jun;2(2):96-103
18340326
Mayo Clin Proc. 2008 Jun;83(6):639-45
18533080
J Thromb Haemost. 2006 Jun;4(6):1246-52
16706967
J Thromb Haemost. 2007 Nov;5(11):2211-8
17697140
Neurology. 2008 Jul 22;71(4):283-7
18645167
J Thromb Thrombolysis. 2006 Feb;21(1):85-9
16475048
Clin Appl Thromb Hemost. 2009 Dec;15(6):609-12
19825911
Cerebrovasc Dis. 2008;26(2):171-7
18628615
Arch Intern Med. 2004 Jun 28;164(12):1319-26
15226166
J Heart Valve Dis. 2007 May;16(3):285-92
17578050
Arch Intern Med. 2008 Jan 14;168(1):63-9
18195197
J Thromb Haemost. 2007 Aug;5(8):1610-6
17663733
Thromb J. 2004 Apr 1;2(1):3
15059286
Int J Epidemiol. 2000 Oct;29(5):891-8
11034974
JAMA. 2001 Jun 13;285(22):2864-70
11401607