What Prosthesis Should Be Used at Valve Re-Replacement After Structural Valve Deterio

[ken]

http://ats.ctsnetjournals.org/cgi/content/abstract/82/6/2123

Ann Thorac Surg 2006;82:2123-2132
© 2006 The Society of Thoracic Surgeons
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Original Articles: Cardiovascular

What Prosthesis Should Be Used at Valve Re-Replacement After Structural Valve Deterioration of a Bioprosthesis?

Lawrence Lau, MBBS Honsa, W.R. Eric Jamieson, MDb,*, Clifford Hughes, FRACSa, Eva Germann, MSb, Florence Chanb

a University of Sydney, Sydney, Australia
b University of British Columbia, Vancouver, Canada

Accepted for publication July 13, 2006.

* Address correspondence to Dr Jamieson, 486 Burrard Building, St. Paul?s Hospital, 1081 Burrard Street, Vancouver, BC, Canada V6Z 1Y6 (Email: [email protected]).

BACKGROUND: The fate of bioprostheses (BP) and mechanical prostheses (MP) after valve re-replacement for bioprostheses is not well-documented. This research compares the late fate of these two valve types after valve re-replacement for structural valve deterioration (SVD) of a bioprosthesis.

METHODS: Between 1975 and 2000, 298 patients had successful aortic valve re-replacements (AVRR) (BP n = 149, average age = 67.1 ± 12.3 years; MP 149, 58.9 ± 10.9) and 442 patients had successful mitral valve re-replacements (MVRR) (BP 155, 65.8 ± 14.1; MP 287, 60.8 ± 11.7) after SVD of a previous BP. Follow-up was five years in all groups.

RESULTS: (1) Aortic position (AVRR): Survival favored MP over BP overall, at 10 years (70.3 ± 5.4% vs 56.7 ± 5.7%, p = 0.0220). This survival advantage was seen to be significant only in patients less than 60 years of age (at 10 years, 85.3 ± 4.9% vs 59.2 ± 9.8%, p = 0.038). No significant difference in survival between the two valve types was observed in patient age groups greater than 60 years of age. Freedoms from valve-specific complications, including reoperation for SVD-thrombosis, major thromboembolism and hemorrhage, and valve-related mortality were not significantly different between the two groups overall. (2) Mitral position (MVRR): Survival favored MP over BP overall (58.6 ± 4.2% vs 42.1 ± 5.2%, p = 0.0011), and in patients greater than 70 years of age (32.8 ± 8.9% vs 16.7 ± 7.1%, p = 0.008). Freedoms from valve-specific complications and valve-related mortality favored MP over BP.

CONCLUSIONS: There was no clinical performance difference between mechanical and bioprosthetic valves in patients greater than 60 years of age upon AVRR. Mechanical valves generally outperformed bioprosthetic valves in all age groups in MVRR.

 

[tobagotwo]

The study of AVR is less than 300 patients, with an average age of 67. This synopsis doesn't mention how many were under 60, and what that range was. This is important in order to determine if the results are significant or from too small or scattered a group to be meaningful. As is, if we assumed that half the people were under 67 (unlikely, as the lower range of ages is double that of those above), we are talking about a group of less than 150 people, which is not enough to be meaningful unless the margin of difference is very large or the numbers are repetetive through other studies.

This does reflect the fact that tissue valves do not last as long in the mitral position. This is is line with studies that do have a significant number of participants.

However, the tissue valves from 1975 (when this study started) do not at all resemble the ones in use today. They lasted six to twelve years on the average at the time. And the surgery itself was certainly cruder and had a much lower success rate. The risk for resurgeries was much higher, as not many had even been done until this study was well underway.

This is one of the reasons today's surgeons still misquote appropriate tissue valve life estimates. They are fed data by salespeople from studies begun over 30 years ago. While the data is technically correct for the situation as it was then, it bears little validity in today's valve choices.

Best wishes,

 

[Adrienne]

This does reflect the fact that tissue valves do not last as long in the mitral position. This is is line with studies that do have a significant number of participants.

Why do tissue valves not last as long in the mitral position? I am curious just in case down the road my mitral valve repair does not last!

By the way, Bob H. (or Tobagotwo), how have you become so informed on all of these cardiac issues? I find it amazing how informed you are.

 

[Superbob]

A Christmas Thanks

A Christmas Thanks

I just want to say a quick thanks that Bob H is around to give us such perceptive analyses of these various studies. And that he is willing to take the time to do so. Thanks!

 

[Susan BAV]

I just want to say a quick thanks that Bob H is around to give us such perceptive analyses of these various studies. And that he is willing to take the time to do so. Thanks!

I too thoroughly appreciate that you compassionately share what you know, Bob.

And Ken, thanks for posting that; it was interesting.

 

[tobagotwo]

And, Ken - my response was entirely to the study, and certainly not a swipe at you.

It's important to bring things into view for thought, and I do appreciate it.

Thank you,

 

[ken]

And, Ken - my response was entirely to the study, and certainly not a swipe at you.

It's important to bring things into view for thought, and I do appreciate it.

Thank you,

No problem, your views are much appreciated.