Warfarin or aspirin in embolism prevention in patients with mitral valvulopathy and atrial fibrillation.
BACKGROUND
Atrial fibrillation (AF) associated to rheumatic mitral valve disease (RMVD) increases the incidence of thromboembolism (TE), with warfarin being the standard therapy, in spite of difficulties in treatment adherence and therapeutic control.


OBJECTIVE
To compare the effectiveness of Aspirin vs Warfarin in TE prevention in patients with AF and RMVD.


METHODS
A total of 229 patients (pts) with AF and RMVD were followed in a prospective and randomized study. The first group consisted of 110 pts receiving Aspirin - 200 mg/day (Group Aspirin - GA) and the second group consisted of 119 pts receiving Warfarin at individually-adjusted doses (Group Warfarin - GW).


RESULTS
There were 15 embolic events in GA and 24 in GW (p = 0.187), of which 21 presented INR < 2.0. Thus, after excluding patients with inadequate INR, there was a higher number of embolic events in GA than in GW (15 vs 3) (p < 0.0061). The GW showed lower treatment adherence (p = 0.001). Neither group presented episodes of major bleeding. Small bleeding episodes were more frequent in the GW (p < 0.01). Increased serum levels of cholesterol and triglycerides constituted a risk factor for a higher number of thromboembolic events in the studied population, with no difference between the groups.


CONCLUSIONS
In patients presenting RMVD with AF for less than a year and no previous embolism, Aspirin is little effective in preventing TE. Patients with lower-risk mitral valvulopathy (mitral regurgitation and mitral biological prosthesis), especially in cases presenting contraindication to or low adherence to Warfarin, Aspirin use can present some benefit in TE prevention.
Instituto do Coração - HCFMUSP, São Paulo, SP - Brazil. m.lavitola@yahoo.com.br
Paulo de Lara
Pde L
Lavitola
Roney Orismar
RO
Sampaio
Walter Amorim de
WA
Oliveira
Berta Napchan
BN
Bôer
Flavio
F
Tarasoutchi
Guilherme Sobreira
GS
Spina
Max
M
Grinberg
D000368:Aged; D000925:Anticoagulants / Q000627:therapeutic use*; D001241:Aspirin / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000378:metabolism*; D001705:Bioprosthesis; D006350:Heart Valve Prosthesis; D006470:Hemorrhage / Q000453:epidemiology; D006801:Humans; D008297:Male; D008944:Mitral Valve Insufficiency / Q000378:metabolism* / Q000628:therapy; D011446:Prospective Studies; D012307:Risk Factors; D013923:Thromboembolism / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D014859:Warfarin / Q000627:therapeutic use*; D016903:Drug Monitoring
D000925:Anticoagulants; D014859:Warfarin; D001241:Aspirin