The reference
The reference
I finally found the reference promised in the post above -- the one that sort of confirmed my choice of Hancock Medtronics Porcine valve over Carpentier-Edwards Pericardium (bovine) valve (though really both are excellent). Here it is, for those interested:
http://www.shvd.org/file/6882.htm
70. Performance of the Carpentier-Edwards SAV and Hancock-II Porcine Bioprostheses in Aortic Valve Replacement
W RE Jamieson1, T E David2, C MS Feindel2, R T Miyagishima1, E Germann1
1University of British Columbia, Vancouver, BC, 2University of Toronto, Toronto, ON, Canada
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OBJECTIVE: The clinical performance of second-generation porcine bioprostheses, specifically with regard to freedom from structural valve deterioration, require comparison. The durability of the CE-SAV and Hancock-II may be influenced by stent designs and tissue preservation methods.
METHODS: The CE-SAV was implanted in 1524 AVRs (mean age 67.6±11.2 years, range 20-90 years; males 67.4%) and H-II in 670 (mean age 65.2±12.1 years, range 18-86 years; males 75.4%) (age p=0.000, gender p=0.00017) from 1982 to 1994. Concomitant coronary artery bypass (CAB) was performed in CE-SAV 43.6% and H-II 39.8% (pNS). The mean valve size for CE-SAV was 23.8±2.6 mm and for H-II, 24.9±2.1 mm (pNS). Previous CAB and valve replacement did not differentiate the groups (pNS). The total follow up was 11,770 years for CE-SAV and 4,813 years for H-II (p=0.0003). The median follow up for CE-SAV was 88.1 months and for H-II 89.2 months. Structural valve deterioration (SVD) was defined for analysis as diagnosed at explant operation. Parameters assessed as independent predictors of SVD were valve type, gender, age <65 or >=65 years (or as continuous), size of valve, lesion, previous CAB, previous valve, previous cardiac surgery, and concomitant CAB.
RESULTS: The overall linearized rate for SVD was 0.986% per patient-year for CE-SAV and 0.457% per patient-year for H-II (p=0.0003). The freedom from SVD (explant operation) at 15 years (patients at risk in parentheses) was as follows: (see Table)
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Actuarial (%)
p Value
Actual (%)
CE-SAV
Hancock II
CE-SAV
Hancock II
Overall
67.7±3.3
77.9±6.5
p = 0.042
85.7±1.3 (68)
88.1±3.2 (18)
<65 years
53.2±4.2
69.0±7.9
p = 0.021
68.8±2.8 (40)
78.5±5.3 (13)
>=65 years
88.4±4.1
100
p = 0.042
96.4±1.0 (28)
100 (5)
66-70 years
87.4±5.5
100
p = NS
93.6±2.3 (11)
100 (3)
>70 years
96.9±1.5
100
p = NS
98.8±0.5 (15)
100 (2)
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The independent predictors of SVD, overall, were previous valve procedure (RR 2.2), concomitant CAB (RR 1.8, negative predictor) and valve type (CE-SAV > H-II) (RR 1.8). Valve type (CE-SAV = HII) was not an independent predictor of SVD for age groupings over 60 years of age. The crude ratio for SVD by year of operation was higher for CE-SAV in 6 and H-II in 5 of 11 years of implantation. The mean time to SVD explant was 122.8 ± 3.9 months for CE-SAV and 115.7 ± 37 months for H-II.
CONCLUSION: The CE-SAV and H-II in AVR both provide satisfactory clinical performance with a low incidence of SVD. There is a trend to less SVD by actual analysis for H-II in patients <65 years. In patients >=65 years (66% of the total population) actual analysis does not differentiate the durability of the prostheses.
Peter
