Objective: Choice of a mechanical or biologic valve in aortic valve replacement remains controversial and rotates around different complications with different time-related incidence rates. Because serious complicatio...Objective: Choice of a mechanical or biologic valve in aortic valve replacement remains controversial and rotates around different complications with different time-related incidence rates. Because serious complications will always “spill over”into mortality, our aim was to perform a meta-analysis on overall mortality after aortic valve replacement from series with a maximum follow-up of at least 10 years to determine the age-and risk factor-corrected impact of currently available mechanical versus stented bioprosthetic valves. Methods: Following a formal study protocol, we performed a dedicated literature search of publications during 1989 to 2004 and included articles on adult aortic valve replacement with a mechanical or stented bioprosthetic valve if age, mortality statistics, and prevalences of well-known risk factors could be extracted. We used standard and robust regression analyses of the case series data with valve type as a fixed variable. Results: We could include 32 articles with 15 mechanical and 23 biologic valve series totaling 17,439 patients and 101,819 patient-years. The mechanical and biologic valve series differed in regard to mean age(58 vs 69 years), mean follow-up(6.4 vs 5.3 years), coronary artery bypass grafting(16%vs 34%), endocarditis(7%vs 2%), and overall death rate(3.99 vs 6.33 %/patient-year). Mean age of the valve series was directly related to death rate with no interaction with valve type. Death rate corrected for age, New York Heart Association classes III and IV, aortic regurgitation, and coronary artery bypass grafting left valve type with no effect. Included articles that abided by current guidelines and compared a mechanical and biologic valve found no differences in rates of thromboembolism. Conclusion: There was no difference in risk factor-corrected overall death rate between mechanical or bioprosthetic aortic valves irrespective of age. Choice of prosthetic valve should therefore not be rigorously based on age alone. Risk of bioprosthetic valve degeneration in young and middle-aged patients and in the elderly and old with a long life expectancy would be an important factor because risk of stroke may primarily be related to patient factors.展开更多
Background: Mechanical valves and bioprostheses are widely used for aortic val ve replacement. Though previous randomised studies indicate that there is no imp ortant difference in outcome after implantation with eith...Background: Mechanical valves and bioprostheses are widely used for aortic val ve replacement. Though previous randomised studies indicate that there is no imp ortant difference in outcome after implantation with either type of valve, knowl edge of outcomes after aortic valve replacement is incomplete. Objective: To pre dict age and sex specific outcomes of patients after aortic valve replacement wi th bileaflet mechanical valves and stented porcine bioprostheses, and to provide evidence based support for the choice of prosthesis. Methods: Meta analysis of published results of primary aortic valve replacement with bileaflet mechanical prostheses(nine reports, 4274 patients, and 25 726 patient years) and stented porcine bioprostheses (13 reports, 9007 patients, and 54 151 patient years) was used to estimate the annual risks of postoperative valve related events and th eir outcomes. These estimates were entered into a microsimulation model, which w as employed to calculate age and sex specific outcomes after aortic valve replac ement. Results: Life expectancy(LE) and event free life expectancy(EFLE) for a 65 year old man after implantation with a mechanical valve or a bioprosthesis we re 10.4 and 10.7 years and 7.7 and 8.4 years, respectively. The lifetime risk of at least one valve related event for a mechanical valve was 48%, and for a bio prosthesis, 44%. For LE and EFLE, the age crossover point between the two valve types was 59 and 60 years, respectively. Conclusions: Meta analysis based micr osimulation provides insight into the long term outcome after aortic valve repla cement and suggests that the currently recommended age threshold for implanting a bioprosthesis could be lowered further.展开更多
Objectives We sought to determine whether changes in quality of life at 18 mon ths following aortic valve replacement differ depending on the use of tissue val ves or mechanical valves. Methods We prospectively studie...Objectives We sought to determine whether changes in quality of life at 18 mon ths following aortic valve replacement differ depending on the use of tissue val ves or mechanical valves. Methods We prospectively studied 73 patients with tiss ue valve replacements and 53 patients with mechanical valve replacements perform ed from April 1998 through March 1999 at Yale-New Haven Hospital. Quality of li fe was measured at baseline and at 18 months using the Medical Outcomes Trust Sh ort Form 36-Item Health Survey. Results Baseline unadjusted mean quality-of-l ife scores were lower in tissue valve recipients than in mechanical valve recipi ents and, for both groups, were generally lower than US population norms. At 18 months postoperatively, quality-of-life scores were greatly improved in both g roups and were comparable to population norms (ie, within one-half a standard d eviation). After adjusting for baseline quality of life, age, and other prognost ic factors in an analysis of covariance, improvements in quality-of-life score s for tissue valve recipients versus mechanical valve recipients were similar. O f 10(8 domains and 2 summary) scales examined, the only significant difference b etween the 2 groups was for the improvement in role limitations due to physical problems (Role Physical), which was more favorable in patients with mechanical v alve implants (P=.04). Conclusions The use of tissue valve implants versus mecha nical valve implants has little influence on improvement in quality of life at 1 8 months following aortic valve replacement. Thus, decisions about whether to ch oose a tissue valve or mechanical valve implant should depend upon other factors such as rates of complications and differences in the life span of the implants .展开更多
文摘Objective: Choice of a mechanical or biologic valve in aortic valve replacement remains controversial and rotates around different complications with different time-related incidence rates. Because serious complications will always “spill over”into mortality, our aim was to perform a meta-analysis on overall mortality after aortic valve replacement from series with a maximum follow-up of at least 10 years to determine the age-and risk factor-corrected impact of currently available mechanical versus stented bioprosthetic valves. Methods: Following a formal study protocol, we performed a dedicated literature search of publications during 1989 to 2004 and included articles on adult aortic valve replacement with a mechanical or stented bioprosthetic valve if age, mortality statistics, and prevalences of well-known risk factors could be extracted. We used standard and robust regression analyses of the case series data with valve type as a fixed variable. Results: We could include 32 articles with 15 mechanical and 23 biologic valve series totaling 17,439 patients and 101,819 patient-years. The mechanical and biologic valve series differed in regard to mean age(58 vs 69 years), mean follow-up(6.4 vs 5.3 years), coronary artery bypass grafting(16%vs 34%), endocarditis(7%vs 2%), and overall death rate(3.99 vs 6.33 %/patient-year). Mean age of the valve series was directly related to death rate with no interaction with valve type. Death rate corrected for age, New York Heart Association classes III and IV, aortic regurgitation, and coronary artery bypass grafting left valve type with no effect. Included articles that abided by current guidelines and compared a mechanical and biologic valve found no differences in rates of thromboembolism. Conclusion: There was no difference in risk factor-corrected overall death rate between mechanical or bioprosthetic aortic valves irrespective of age. Choice of prosthetic valve should therefore not be rigorously based on age alone. Risk of bioprosthetic valve degeneration in young and middle-aged patients and in the elderly and old with a long life expectancy would be an important factor because risk of stroke may primarily be related to patient factors.
文摘Background: Mechanical valves and bioprostheses are widely used for aortic val ve replacement. Though previous randomised studies indicate that there is no imp ortant difference in outcome after implantation with either type of valve, knowl edge of outcomes after aortic valve replacement is incomplete. Objective: To pre dict age and sex specific outcomes of patients after aortic valve replacement wi th bileaflet mechanical valves and stented porcine bioprostheses, and to provide evidence based support for the choice of prosthesis. Methods: Meta analysis of published results of primary aortic valve replacement with bileaflet mechanical prostheses(nine reports, 4274 patients, and 25 726 patient years) and stented porcine bioprostheses (13 reports, 9007 patients, and 54 151 patient years) was used to estimate the annual risks of postoperative valve related events and th eir outcomes. These estimates were entered into a microsimulation model, which w as employed to calculate age and sex specific outcomes after aortic valve replac ement. Results: Life expectancy(LE) and event free life expectancy(EFLE) for a 65 year old man after implantation with a mechanical valve or a bioprosthesis we re 10.4 and 10.7 years and 7.7 and 8.4 years, respectively. The lifetime risk of at least one valve related event for a mechanical valve was 48%, and for a bio prosthesis, 44%. For LE and EFLE, the age crossover point between the two valve types was 59 and 60 years, respectively. Conclusions: Meta analysis based micr osimulation provides insight into the long term outcome after aortic valve repla cement and suggests that the currently recommended age threshold for implanting a bioprosthesis could be lowered further.
文摘Objectives We sought to determine whether changes in quality of life at 18 mon ths following aortic valve replacement differ depending on the use of tissue val ves or mechanical valves. Methods We prospectively studied 73 patients with tiss ue valve replacements and 53 patients with mechanical valve replacements perform ed from April 1998 through March 1999 at Yale-New Haven Hospital. Quality of li fe was measured at baseline and at 18 months using the Medical Outcomes Trust Sh ort Form 36-Item Health Survey. Results Baseline unadjusted mean quality-of-l ife scores were lower in tissue valve recipients than in mechanical valve recipi ents and, for both groups, were generally lower than US population norms. At 18 months postoperatively, quality-of-life scores were greatly improved in both g roups and were comparable to population norms (ie, within one-half a standard d eviation). After adjusting for baseline quality of life, age, and other prognost ic factors in an analysis of covariance, improvements in quality-of-life score s for tissue valve recipients versus mechanical valve recipients were similar. O f 10(8 domains and 2 summary) scales examined, the only significant difference b etween the 2 groups was for the improvement in role limitations due to physical problems (Role Physical), which was more favorable in patients with mechanical v alve implants (P=.04). Conclusions The use of tissue valve implants versus mecha nical valve implants has little influence on improvement in quality of life at 1 8 months following aortic valve replacement. Thus, decisions about whether to ch oose a tissue valve or mechanical valve implant should depend upon other factors such as rates of complications and differences in the life span of the implants .
