Table 1.

Main comparative studies after bioprosthetic valve implantation with outcome focused on thromboembolic events with no specific antithrombotic therapy

Author-Year	N	Study design and follow-up (months)	Location and incidence of embolic events (%/person-year)	Stipulated therapy	Conclusion (embolic events)
Cohen et al12 1979	323	Retrospective; 84	ABP: 0.55*	NAT: sinus Rhythm WAR: AF	Low incidence;
			MBP: 3.9*
Fuster et at13 1982	302	Retrospective; 120	ABP: 0.26#	Not informed	P < 0.01; BPM high risk of events;
			MBP: 0.30#
lonescu et al14 1982	366	Retrospective; 120	MBP: 0.6	Not used	Very low risk
Cohn et al 15 1984	663	Retrospective; 108	ABP: 0.07	Not informed	-
Joyce et al16 1984	469	Retrospective; 36.2	ABP: 0.011-0.024	Not informed	-
			MBP: 0.01-0.028
Gallo et al17 1985	189	-	ABP: 0.5	Not informed
			MBP: 2.3
Hartz et al18 1986	589	Retrospective; 38	ABP: 208 pcts	Not informed	Low incidence
			MBP: 209 pts
			Total: 0.3 a 0.8
Gonzalez-Lavin et al19 1988	240	Retrospective; 100	ABP: 0.9	Not used	Peak of events between 60-70 months.
Braile et al20 1991	663	Retrospective, 132	MBP: 0.3	-	CVA - 0.3%
Babin-Ebell et al21 1995	57	Retrospective. 6	ABP: 0.035-1.75	Not used
Orszulak et al22 1995	561	Retrospective; 42	ABP: 1.57	NAT overall;	p = 0.01 Higher risk for the elderly (> 73 years), AF decreased EF.

N: sample size; AF: atrial fibrillation; ABP: aortic bioprosthesis; MBP: mitral bioprosthesis; NAT: No antithrombotic therapy; EF: ejection fraction; pts: Patients; CVA: cerebrovascular accident; WAR: Warfarin; p: statistical significance;

^*Embolic events only occurred in patients with AF.