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Three Part Question

In patients requiring a [tricuspid valve replacement] is a [mechanical valve or a biological valve] better for [long-term survival and lower morbidity].

Clinical Scenario

You are about to operate on a 32 year old i.v. drug abuser who has been under the care of your cardiologists for 8 weeks with Tricuspid valve endocarditis. She has successfully undergone 6 weeks of antibiotic therapy and 3 blood cultures off antibiotics have all been negative. However she has severe tricuspid regurgitation with hepatic congestion and peripheral oedema and requires tricuspid replacement. You wonder whether to use a biological or mechanical valve.

Search Strategy

Medline 1950–April 2007 using the OVID interface
[exp Tricuspid Valve/ OR tricuspid valve.mp] AND [exp Heart Valve Prosthesis/ OR valve replacement.mp. OR exp Heart Valve Prosthesis Implantation/] AND [survival.mp OR outcome.mp OR mortality.mp] LIMIT to Human/english

Search Outcome

A total of 561 papers were found of which thirteen relevant papers were relevant

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Rizzoli et al, 2004, Italy	1967 -2002 n= 1258; mean age=49.3 Biological =646 Mechanical =514 Isolated TVR ratio (0.36) Re-operation ratio (0.53)	Meta-analysis (Level 1a)	Survival Hazard ratio	(Bio[%]vs. Mec [%], p value) OR 1.07 ( 95% CI, 0.85 to 1.35, p = 0.60)	Differences were trivial Favoured mechanical at 1 and 15 years ; biological at 10 years Methodological limitations due to inclusion of observational studies; results are less reliable
			Freedom from Re-operation	OR 1.24 ( 95% CI, 0.67 to 2.31, p = 0.50)
			Survival free –Re-operation	OR 0.86 ( 95% CI, 0.70 to 1.05, p = 0.14)
			Thrombosis incidence patient/yrs	0.87%
			Valve degeneration incidence patient/yrs	1.02%
Ratnatunga et al, 1998, UK	1986 -1997 N=425, mean age=57 Biological =225 Mechanical =200 Isolated TVR ratio (0.38) Re-operation ratio (0.04)	Retrospective Cohort Study (level 2b)	Survival	(Bio[%]vs. Mec [%], p value) 30 days= 18.8 vs. 15.6, p = 0.52, 5 yrs = 70.5 vs. 74, 10 yrs = 61.5 vs. 57.9, 15 yrs = 47.7 vs. 33.9	No superiority Registry Retrospective
			Freedom from re-operation	1 yr = 99.3 vs. 98, 10 yrs = 97.7 vs. 97.1 (p = 0.59)
			Survival free –Re-operation	1 yr = 70 vs. 72.4, 10 yrs = 46.7 vs. 32.3 (p = 0.55)
			Thrombosis incidence patient/yrs	0.134%
			Valve degeneration patient/yrs	0.119%
			Risk predictors of mortality	Year of operation, age, number of valves implanted
Farinas et al, 1996, France	1969 - 1993 N=55, mean age=49 Biological = 47 Mechanical = 8 Isolated TVR ratio (0.27)	Single centre Retrospective Cohort Study (level 2b)	Mortality 30 days	23.6 %	Retrospective, small sample size, heterogeneity of patients and surgical techniques.
			Thrombosis incidence patient/yrs	0%
			Valve degeneration patient/yrs	0.674%
			Risk predictors of operative mortality	High systolic pulmonary pressure, bypass time, abnormal ejection fraction
Do et al, 2000 France	1978 -1998 n=32, mean age 48 Biological =26 Mechanical = 6 (Bio[%]vs. Mec [%] ) Isolated TVR ratio ( 1 vs. 1) Re-operation ratio (0.84)	Single centre Retrospective Cohort Study (level 2b)	Survival	5 yrs = 63%. 10 yrs = 47%	Included only isolated TVR - improves NHYA class Retrospective, small sample size, heterogeneity of patients and surgical techniques.
			Thrombosis incidence patient/yrs	3.33%
			Valve degeneration incidence patient/yrs	2.27%
Carrier et al, 2003, Canada	1977 -2002 N=97; mean age=52 Biological =82 Mechanical =15 (Bio[%]vs. Mec [%] ) Isolated TVR (38 vs. 73, p =0.01) Re-operation (78 vs. 80, p = 0.8)	Single centre Retrospective Cohort Study (level 2b)	Survival	(Bio[%]vs. Mec [%], p value) 30 days = 17 vs. 20, p = 0.7. 1 yr = 67 ± 5 vs. 60 ± 13, p = 0.9. 5yrs = 56 ± 6 vs. 60 ± 13.	Favoured bio prostheses – life expectancy unrelated to the type of prostheses used at long-term follow-up Retrospective, small sample size, heterogeneity of patients and surgical techniques.
			Freedom from Re-operation	1 yr = 100 ± 3 vs. 91 ± 9, p = 0.2. 5 yrs = 97 ± 3 vs. 91 ± 9
			Survival free –Re-operation	1 yr = 66 ± 5 vs. 53 ± 13, p = 0.8. 5 yrs = 52 ± 6 vs. 53 ± 13
			Thrombosis incidence patient/yrs	4.55%
			Valve degeneration incidence patient/yrs	5.45%
			Risk predictors of mortality	Age, CPBT
Munro et al, 1995, Canada	1977 -2002 N=97, Mean Age=55 Biological =83 Mechanical =14 Isolated TVR ratio (0.31)	Single centre Retrospective Cohort Study (level 2b)	Survival Early mortality Late mortality	(Bio[%]vs. Mec [%], p value) 14.4 vs. 14.5, p = NS 9.2% pt/yr (isolated TVR 12.2% vs. 7.9% TVR + others)	Favoured bio-prostheses – low rate of structural valve deterioration and avoidance of thrombosis Retrospective, small sample size, heterogeneity of patients and surgical techniques.
			Freedom from Re-operation	5 yr = 97 ± 2.9 vs. 87 ± 12, 10 yrs = 82.3 ± 11 vs. 86.7 ± 12.4
			Thrombosis incidence patient/yrs	1.92%
			Valve degeneration patient/yrs	0.325%
Kaplan et al, 2002,	1980 -2000 N=129, mean age=36 Biological =32 Mechanical =97 (Bio[%]vs. Mec [%] ) Isolated TVR ratio ( 0.31 vs. 0.21) Re-operation ratio (0.79)	Single centre Retrospective Cohort Study (level 2b)	Survival Hazard ratio	(Bio[%]vs. Mec [%], p value) OR 0.545 ( 95% CI, 0.199 to 1.494, p = 0.238)	No difference Recommend modern bi-leaflet mechanical valve Retrospective, heterogeneity of patients and surgical techniques.
			Early mortality Mid-term mortality	31.2% vs. 20.6% 9% vs. 9%
			Survival free –Re-operation	OR 0.225 ( 95% CI, 0.005 to 9.77, p = 0.440)
			Re-operation	9% vs. 6.5%
			Thrombosis incidence patient/yrs	1.28%
			Valve degeneration incidence patient/yrs	1.74%
Dalrymple-Hay et al, 1999, UK	1973 - 1996 n=32;mean age=59 Biological =52 Mechanical =35 (Bio[%]vs. Mec [%] ) Isolated TVR ratio (0.31 vs. 0.09) Re-operation ratio (0.52)	Single centre Retrospective Cohort Study (level 2b)	Survival Hazard ratio	(Bio[%]vs. Mec [%], p value) OR 0.984 ( 95% CI, 0.851 to 1.137, p = 0.827)	Bio prothesis – initial durability and low operation rate Retrospective, small sample size, heterogeneity of patients and surgical techniques.
			Freedom from Re-operation	5 yrs= 97 ± 2.5 vs. 86 ± 7.4, 10 yrs = 89 ± 6.3 vs. 74 ± 9.9, 15 yrs = 70 ± 12 vs. 68 ± 11 p = 0.2
			Thrombosis incidence patient/yrs	1.76%
			Valve degeneration incidence patient/yrs	0.709%
			Risk predictors of mortality	Advanced NHYA functional class, CPBT
Hayashi J et al, 1996, Japan	1978 -1995 N=29, mean age=40 Biological = 14 Mechanical = 15 Isolated TVR ratio (0.347) Re-operation ratio (0.35)	Single centre Retrospective Cohort Study (level 2b)	Survival Hazard ratio	(Bio[%]vs. Mec [%], p value) OR 1.40 ( 95% CI, 0.358 to 5.469, p = 0.628)	Both similar; suggested patient – specific selection of the prothesis Retrospective, small sample size, heterogeneity of patients and surgical techniques.
			Thrombosis incidence patient/yrs	1%
			Valve degeneration patient/yrs	3.19%
			Risk predictors of mortality	Functional class, baseline diseases
Scully et al, 1995	1978 - 1993 N=60, Mean Age 50 Biological =28 Mechanical =32 (Bio[%]vs. Mec [%] ) Isolated TVR (25 vs. 44) Re-operation ratio (0.75)	Single centre Retrospective Cohort Study (level 2b)	Survival All patients, Hospital Survivors	(Bio[%]vs. Mec [%], p value) 38 ± 15 vs. 38 ± 11, p = NS. 50 ± 12 vs. 56 ± 20, p = NS	Both equally effective Retrospective, small sample size, heterogeneity of patients and surgical techniques.
			Re-operation	3 had re-operation (2 Bio and 1 Mec.)
			Thrombosis incidence patient/yrs	0.50%
			Valve degeneration patient/yrs	1.71%
Nooten et al, 1995, Belgium	1967 -1987 N=146, Mean Age=51 Biological =69 Mechanical =77 Isolated TVR ratio (0.16) Re-operation ratio (0.45)	Single centre Retrospective Cohort Study (level 2b)	Survival Hazard ratio	(Bio[%]vs. Mec [%], p value) OR 0.972 ( 95% CI, 0.613 to 1.539, p = 0.903)	Bio prothesis better than old mechanical prothesis (p = 0.04). When follow up period was split < 7 years no difference. But > 7 years new mechanical prothesis better than bio prothesis, p = 0.05) Retrospective
			Survival free –Re-operation	OR 0.861 ( 95% CI, 0.698 to 1.063, p = 0.163)
			Thrombosis incidence patient/yrs	0.748%
			Valve degeneration patient/yrs	0.417%
			Risk predictors of mortality	Presence of icterus
Chang et al, 2006, Korea	1978 -2003 n=138; mean age=44 Biological =35 Mechanical =103 (Bio[%]vs. Mec [%] ) Isolated TVR (46 vs. 24 ) Re-operation (40 vs. 63)	Single Centre Retrospective Cohort Study (level 2b)	Survival at 15 yrs	Biological 70.2 ± 10 Mechanical 66 ± 19, p = 0.18	Similar long-term outcomes Need to prevent thrombosis in early post –period in Mechanical valves Greater chance of re-operation in biological prostheses Retrospective, heterogeneity of patients and surgical techniques.
			Freedom from Re-operation at 15 yrs	Biological 55.1 ± 13.8 Mechanical 86 ± 6.2
			Survival free –Re-operation 5 yr/10 yr/15 yr	Bio vs Mech: 5 yr = 91 ± 0.6 vs. 98 ± 0.8,p =0.4 . 10 yr = 85 ± 0.9 vs. 92 ± 1.0. 15 yr = 84 ± 0.9 vs. 92 ± 1.4
			Thrombosis incidence patient/yrs	(overall; valve) Both – (1.41%; 1.28%) Mechanical - (2.11%; 1.92%)
			Valve degeneration incidence patient/yrs	Both - 0.84% Bio-prostheses – 2.68%
			Risk predictors of late mortality	Preoperative ascites and peripheral oedema
Filsoufi et al, 2005, USA	1985 - 1999 N=81;mean age=61 Biological =34 Mechanical =47 Isolated TVR (31% ) Re-operation (63%)	Single centre Retrospective Cohort Study (level 2b)	Survival 2.5 yrs, 5 yrs, 10 yrs	(Bio[%]vs. Mec [%], p value) 2.5 = 80 vs. 84. 5 = 60 vs. 69. 10 = 45 vs. 59	No superiority Overall high mortality Heart failure common cause of early and late mortality Retrospective, small sample size, heterogeneity of patients and surgical techniques.
			In hospital mortality	15 vs. 32, p = 0.06
			Thrombosis	(Bio[%]vs. Mec [%] ) 0% vs. 8%
			Valve degeneration	(Bio[%]vs. Mec [%] )4% vs. 0%
			Risk predictors of late mortality	Organic aetiology
Rizzoli et al, 1998, Italy	N=101, mean age 46 Biological =78 Mechanical =23 (Bio[%]vs. Mec [%] ) Isolated TVR ratio ( 0.23 vs. 0.26) Re-operation ratio (0.73)	Single centre Retrospective Cohort Study (level 2b)	Survival Hazard Ratio	(Bio[OR]vs. Mec [OR], p value) 1 yr = (0.87 vs. 0.93). 5 yrs = (0.73 vs. 0.79). 10 yrs = (0.39 vs. 0.56). 15 yrs = (0.28 vs. 0.45)	Retrospective, small sample size, heterogeneity of patients and surgical techniques.
			Freedom from Re-operation	1 yr = (0.96 vs. 1). 5 yrs = (0.96 vs. 0.917). 10 yrs = (0.84 vs. 0.84). 15 yrs = (0.53 vs. 0.62)
			Survival free –Re-operation	1 yr = (0.85 vs. 0.93). 5 yrs = (0.71 vs. 0.72). 10 yrs = (0.45 vs. 0.46). 15 yrs = (0.23 vs. 0.28)
			Thrombosis incidence patient/yrs	2.22%
			Valve degeneration incidence patient/yrs	1.96%

Comment(s)

The published series are few and are limited by small sample size, often spanning from the 1960s through 1990s. We identified thirteen papers which have compared both biological and mechanical valves in the tricuspid position including a meta-analysis. The meta-analysis by Rizzoli comparing 646 biological and 514 mechanical prostheses from 11 studies did not find a difference in the early and late survival, or re-operations. The meta-analysis included series starting in the 1960s and included patients with first-generation valve prostheses. Among 391 patients discharged with mechanical prostheses, the pooled 1,5,10, and 15-year survival of the hospital-discharged patients was 86.9%, 73.5%, 60.2%, and 47.8%, respectively; among 477 patients discharged with tricuspid bioprostheses, survival was 86.5%, 73.6%, 62%, and 46.7%, respectively. Five-year survival was identical. Differences were trivial, favouring mechanical prostheses at 1-year and at 15-years, favouring biological prostheses at 10-years. The median incidence of mechanical tricuspid valve thrombosis reported in the meta-analysis, was 1.28% patient-years. There was a large variability in the incidence of thrombosis reported in these series. The series of Ratnatunga and Farinas report the lowest incidence; Do and Carrier report the highest. The series of Ratnatunga, Farinas, and Munro reported lower incidence of structural valve deterioration; Do and Carrier reported the highest. Overall, 21 mechanical valve thromboses and 37 deterioration episodes were reported in the meta-analysis. The incidence rate of thrombosis was 0.87% patient/year (In comparison to MVR:0.54%/patient-year and AVR:0.33%/patient-year) and the incidence of valve deterioration was 1.02% patient/year. The difference was not significant(p=0.25). The risk of reoperation reported was 4.7%/patient-year for bioprostheses and 2.2%/patient-year for mechanical prostheses. Filsoufi reported 81 cases of tricuspid valve replacement of which 34 were biological and 47 were mechanical,(25 isolated). They had an overall mortality of 22%. The common cause of death was heart failure in both early and late death. Survival at 2.5,5 and 10years for biological prostheses were 80%, 60% and 45% and 84%, 69% and 59% for mechanical prostheses. There was no clear superiority of one prosthesis over another. Carrier reported 97 patients with tricuspid valve replacement, of which 82 were biological and 15 were mechanical. Mortality in the biological group was 17% and 20% in the mechanical group. Congestive heart failure was the most significant cause of long term death. One and 5-year survival rates were 67±5% and 56±6% with bioprostheses and 60±13% and 60±13% in the mechanical group. They favoured biological prostheses. Kaplan reported 122 patients with tricuspid valve replacement, which included biological prostheses in 32 patients and mechanical prostheses in 97 patients. Early mortality was 24.5% and 9.7% late mortality. Mean survival time was 159±19months for mechanical prostheses and 85.7±12.1 months for biological prostheses. They recommend mechanical valve prostheses. Dalrymple reported 87 patients with tricuspid valve replacement of which 53 were biological and 35 were mechanical. They reported an early mortality of 10.3% which is the lowest of all the papers documented. Six mechanical valves needed re-operation, five for prosthetic valve thrombosis and one for mechanical failure secondary to pannus formation. Five biological prostheses needed re-operation, two for prosthetic valve endocarditis and three for prosthetic valve degeneration. They recommend the use of biological prostheses because of its initial durability and low re-operation rate.Ratnatunga from United Kingdom did a retrospective UK Heart Valve registry study of all the valves done between 1986 to 1997 and reported 425 patients with tricuspid valve replacement. (225 biological and 200 mechanical). Early mortality was 17.3% and mortality for biological was 18.6% and 15.6% for mechanical prostheses. One, 5 and 10 year survival was 70.5%, 61.5% and 47.7% for biological prostheses and 74%, 57.9% and 33.9% for mechanical prostheses.. The remaining studies which tabulated, didn't find any difference between the prostheses. In summary, two series recommend biological prostheses and one series recommends mechanical prostheses. The overall mortality for TVR ranged from 10.3% to 27%. Most of these studies did not find any superiority between the prostheses used. Rizzoli made the following observations after their meta-analysis."(1) Tricuspid position is no exception to the rule that patients more than 65-70 years obtain the largest advantage from bioprostheses and younger patients from mechanical prostheses. (2) The extent and the severity of cardiac disease might suggest, in some cases, a limited expectation of life and therefore might favour the use of biological prostheses in younger patients, as concluded by Carrier. On the other hand, concomitant use of left-sided mechanical prostheses favours the same valve for the right heart. (3) Small size patients with small right ventricles may benefit from the superior haemodynamics of the low profile bileaflet valve as opposed to the "largest" bioprostheses, which is prone to develop mural cusp pannus and thrombosis. (4) Rizzoli, in his study found that 97% of living patients with biological tricuspid prostheses receives anticoagulant treatment, making the need for anticoagulation an unreliable choice of valve type.

Clinical Bottom Line

There are no major differences between the insertion of a mechanical or biological tricuspid valve. Aggregating the available data it is found that the reoperation rate is similar with bioprosthetic degeneration rate being equivalent to the mechanical thrombosis rate. Conversely up to 95% of patients with a bioprosthesis still receive anticoagulation. Survival in over 1000 prostheses pooled by meta-analysis was equivalent between biological and mechanical valves.

References

1. Rizzoli G, Vendramin I, Nesseris G, Bottio T, Guglielmi C, Schiavon L. Biological or mechanical prostheses in tricuspid position? A meta-analysis of intra-institutional results. Annals of Thoracic Surgery 77(5):1607-14, 2004.
2. Ratnatunga CP, Edwards MB, Dore CJ, Taylor KM. Tricuspid valve replacement: UK Heart Valve Registry mid-term results comparing mechanical and biological prostheses.[see comment]. Annals of Thoracic Surgery 66(6):1940-7, 1998.
3. Farinas JM, Leclerc Y, Antchouey AM, Mercier LA. [Tricuspid valve replacement: long-term clinical and echocardiographic follow-up]. [French]. Annales de Chirurgie 50(8):707-12, 1996.
4. Do QB, Pellerin M, Carrier M, Cartier R, Hebert Y, Page P, Perrault LP, Pelletier LC. Clinical outcome after isolated tricuspid valve replacement: 20-year experience. Canadian Journal of Cardiology 16(4):489-93, 2000.
5. Carrier M, Hebert Y, Pellerin M, Bouchard D, Perrault LP, Cartier R, Basmajian A, Page P, Poirier NC. Tricuspid valve replacement: an analysis of 25 years of experience at a single center. Annals of Thoracic Surgery 75(1):47-50, 2003.
6. Munro AI, Jamieson WR, Tyers GF, Germann E. Tricuspid valve replacement: porcine bioprostheses and mechanical prostheses. Annals of Thoracic Surgery 60(2 Suppl):S470-3; discussion S473-4, 1995.
7. Filsoufi F, Anyanwu AC, Salzberg SP, Frankel T, Cohn LH, Adams DH. Long-term outcomes of tricuspid valve replacement in the current era. Annals of Thoracic Surgery 80(3):845-50, 2005.
8. Kaplan M, Kut MS, Demirtas MM, Cimen S, Ozler A. Prosthetic replacement of tricuspid valve: bioprosthetic or mechanical. Annals of Thoracic Surgery 73(2):467-73, 2002.
9. Dalrymple-Hay MJ, Leung Y, Ohri SK, Haw MP, Ross JK, Livesey SA, Monro JL. Tricuspid valve replacement: bioprostheses are preferable. Journal of Heart Valve Disease 8(6):644-8, 1999.
10. Hayashi J, Saito A, Yamamoto K, Watanabe H, Ohzeki H, Eguchi S. Is a bioprosthesis preferable in tricuspid valve replacement? Thoracic & Cardiovascular Surgeon 44(5):230-3, 1996.
11. Scully HE, Armstrong CS. Tricuspid valve replacement. Fifteen years of experience with mechanical prostheses and bioprostheses. Journal of Thoracic & Cardiovascular Surgery 109(6):1035-41, 1995.
12. Van Nooten GJ, Caes F, Taeymans Y, Van BY, Francois K, De BD, Deuvaert FE, Wellens F, Primo G. Tricuspid valve replacement: postoperative and long-term results. Journal of Thoracic & Cardiovascular Surgery 110(3):672-9, 1995.
13. Chang BC, Lim SH, Yi G, Hong YS, Lee S, Yoo KJ, Kang MS, Cho BK. Long-term clinical results of tricuspid valve replacement. Annals of Thoracic Surgery 81(4):1317-23, discussion 1323-4, 2006.
14. Filsoufi F, Anyanwu AC, Salzberg SP, Frankel T, Cohn LH, Adams DH. Long-term outcomes of tricuspid valve replacement in the current era. Annals of Thoracic Surgery 80(3):845-50, 2005.
15. Rizzoli G, De PL, Bottio T, Minutolo G, Thiene G, Casarotto D. Prosthetic replacement of the tricuspid valve: biological or mechanical? Annals of Thoracic Surgery 66(6 Suppl):S62-7, 1998.