34-Year durability of a DeBakey Surgitool mechanical aortic valve prosthesis
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《血管的通路杂志》
Department of Cardiac Surgery, University Hospital Grosshadern, Ludwig-Maximilians-University, Marchioninistrasse 15, 81377 Munich, Germany
Abstract
Background: The DeBakey Surgitool mechanical aortic valve prosthesis was the first mechanical prosthetic valve in which pyrolitic carbon was used. This valve was on the market from 1969 to 1978 and approximately 3300 valves were implanted in this lapse worldwide. Report: We present a DeBakey Surgitool mechanical aortic valve prosthesis implanted in 1972, which has been functioning for almost 34 years and still presents a good performance. Comment: Spontaneous strut fractures associated with haemodynamic complications and death, even in asymptomatic patients, was the reason to withdraw this prosthetic valve from the market. However, a prophylactic replacement of DeBakey Surgitool valve was not indicated in our patient due to the excellent prosthesis compliance.
Key Words: Aortic valve replacement; Mechanical prosthesis; Durability; Surgitool DeBakey
1. Background
The mechanical heart valve prosthesis DeBakey Surgitool was designed in 1967 by DeBakey and Cromie [1]. The valve was constructed as a closed ball-cage suspended from a prosthetic ring and presented three titanium struts, which closed the ball-cage anchored to the ring (Fig. 1). The initial DeBakey Surgitool valve experienced modifications which led to three different models. The first model presented bare titanium struts anchored in a dacron-covered ring and a pyrolite poppet. The valvular orifice was modified first with polyethylene (model 2) and afterwards with pyrolate originating the model 3 of this valve [2]. The soft carbon ball was structured in three carbon and pyrolite layers, the inner layer being coated with tungsten to render the ball radio-opaque [2].
These valve models were retired from the market in 1978 due to a high incidence of strut fractures leading to sudden death in three cases, although the valve components were supposed to achieve a long durability [3].
2. Case report
A 69-year-old woman was admitted to our department with a 6-month evolution effort dyspnoea, reduced heart ejection fraction and other accompanying diseases, including chronic hepatitis C. The cardiac medical record of the patient included an aortic valve replacement in 1972 (DeBakey Surgitool aortic valve prosthesis), an AV-Block I as well as a newly diagnosed combined mitral failure.
Her blood pressure was 110/70 mmHg; heart rate, 75 beats/min and regular; and temperature, 37.2 °C. Cardiac auscultation revealed a grade 3/6 systolic murmur that was audible at the apex and a prosthetic click. Her lungs were clear on auscultation. Chest X-ray showed an enlarged configuration of the heart as well as the implanted prosthesis in aortic position (Fig. 1). Current status of her hepatitis C chronic infection was assessed by reverse transcription-polymerase chain reaction (RT-PCR), revealing a serum HCV-RNA above 1500 kIU/ml.
The preoperative diagnostic procedures included a heart angiography and transthoracic echocardiographical analysis. Angiographic analysis revealed a light reduced left ventricular function and no signs of coronary stenoses. Transthoracic echocardiography, including Doppler flow mapping, showed a severe mitral regurgitation, dilatation of the left atrium without presence of thrombus as well as moderate tricuspid regurgitation. It also showed a normally functioning DeBakey Surgitool aortic valve prosthesis. The mean aortic pressure gradient across the Surgitool aortic valve was 20 mmHg and no valve insufficiency or periprosthetic leak was detected. Real time 3-D transthoracic echocardiography was performed, showing a normal function of the prosthetic ball and no deformation of the cage struts (Fig. 2). Mitral valve replacement was scheduled on the basis of these findings.
The operation was performed through a median sternotomy. After preparation of the anatomical structures, both caval veins as well as the ascending aorta were cannulated to establish the cardiopulmonary bypass. The mitral valve was replaced by means of a trans-septal approach with a 29-mm Carpentier-Edwards Perimount Magna bioprosthesis (Edwards Lifesciences, Saint-Prex, Switzerland). The mitral valve replacement was performed with a bioprosthesis in order to reduce the anticoagulation's range from 2.5–3.5 INR values to 2–3 INR values. The aortic valve prosthesis was intraoperatively inspected. The mechanical function was assessed as correct and no increased wearing signs were detected. Due to these reasons the mechanical valve prosthesis was not replaced. The patient recovered uneventfully and was discharged 2 weeks after the procedure. Anticoagulation with an INR between 2.0 and 3.0 was instituted. Good function of both prostheses was confirmed in the early postoperative period and in a 3-month follow-up.
3. Discussion
The DeBakey Surgitool aortic valve prosthesis was introduced in the market in 1967 and became an alternative to the previously commercialised Starr-Edwards ball valve prosthesis (S-E). Both valves presented a similar design consisting of a caged ball, a cloth-covered ring and a cage from bare metal struts. The DeBakey Surgitool prosthesis presented several modifications in comparison to the original S-E prosthesis, presenting a ball made of pyrolitic carbon and a bare metal cage instead of a cloth-covered one. This valve was the first mechanical valve in which pyrolitic carbon was used, an alloy known for its durability and biocompatibility [4,5]. The bare metal ring was designed to reduce the complication rates attached to the cloth-covered ring of the S-E prosthesis, including haemolysis or thromboembolic phenomena related to cloth wear and foreign-body derived complications [6].
Due to demonstrated strut fractures in three cases of mechanical failure of the DeBakey Surgitool aortic valve prosthesis, it was withdrawn from the market in 1978. It was postulated that these fractures had an origin in the different hardness of the involved materials, as well as a weak junction between the cage and the ring which led to stress strut fractures. In the absence of mechanical dysfunction due to strut fractures, DeBakey Surgitool aortic valve prosthesis has been reported as an example of durability of mechanical valves and its prophylactic replacement has not been recommended [7,8]. In our patient, a good mechanical function was pre- and postoperative echocardiographically assessed. Intraoperative inspection evaluation of the DeBakey Surgitool aortic valve prosthesis revealed no increased wearing signs. Due to these reasons, and in consonance with the current literature, we decided not to replace prophylactically the aortic valve.
References
DeWall RA, Qasim N, Carr L. Evolution of mechanical heart valves. Ann Thorac Surg 2000; 69:1612–1621.
Scott SM, Sethi GK, Bridgman AH, Takaro T. Experience with the DeBakey-Surgitool aortic prosthetic valve. Ann Thorac Surg 1976; 21:483–486.
Urgent Device Recall Letter Travenol Laboratories Inc. May 22, 1978;.
Schoen FJ, Titus JL, Lawrie GM. Durability of pyrolytic carbon-containing heart valve prostheses. J Biomed Mater Res 1982; 16:559–570.
Bokros JC, Gott VL, La Grange LD, Fadall AM, Vos KD, Ramos MD. Correlations between blood compatibility and heparin adsorptivity for an impermeable isotropic pyrolytic carbon. J Biomed Mater Res 1969; 3:497–528.
Angelini GD, Kulatilake EN, Armistead SH. Right coronary artery occlusion by cloth from a Starr-Edwards aortic valve prosthesis. Thorac Cardivasc Surg 1984; 32:379–380.
Butany J, Naseemuddin A, Nair V, Feindel CM. DeBakey Surgitool mechanical heart valve prosthesis, explanted at 32 years. Cardiovasc Pathol 2004; 13:345–346.
Von Der Emde JJ, Eberlein U, Breme JJ. Asymptomatic strut fracture in DeBakey-Surgitool aortic valves: incidence, management, and metallurgic aspects. Tex Heart Inst J 1990; 17:223–227.(Andres Beiras-Fernandez, )
Abstract
Background: The DeBakey Surgitool mechanical aortic valve prosthesis was the first mechanical prosthetic valve in which pyrolitic carbon was used. This valve was on the market from 1969 to 1978 and approximately 3300 valves were implanted in this lapse worldwide. Report: We present a DeBakey Surgitool mechanical aortic valve prosthesis implanted in 1972, which has been functioning for almost 34 years and still presents a good performance. Comment: Spontaneous strut fractures associated with haemodynamic complications and death, even in asymptomatic patients, was the reason to withdraw this prosthetic valve from the market. However, a prophylactic replacement of DeBakey Surgitool valve was not indicated in our patient due to the excellent prosthesis compliance.
Key Words: Aortic valve replacement; Mechanical prosthesis; Durability; Surgitool DeBakey
1. Background
The mechanical heart valve prosthesis DeBakey Surgitool was designed in 1967 by DeBakey and Cromie [1]. The valve was constructed as a closed ball-cage suspended from a prosthetic ring and presented three titanium struts, which closed the ball-cage anchored to the ring (Fig. 1). The initial DeBakey Surgitool valve experienced modifications which led to three different models. The first model presented bare titanium struts anchored in a dacron-covered ring and a pyrolite poppet. The valvular orifice was modified first with polyethylene (model 2) and afterwards with pyrolate originating the model 3 of this valve [2]. The soft carbon ball was structured in three carbon and pyrolite layers, the inner layer being coated with tungsten to render the ball radio-opaque [2].
These valve models were retired from the market in 1978 due to a high incidence of strut fractures leading to sudden death in three cases, although the valve components were supposed to achieve a long durability [3].
2. Case report
A 69-year-old woman was admitted to our department with a 6-month evolution effort dyspnoea, reduced heart ejection fraction and other accompanying diseases, including chronic hepatitis C. The cardiac medical record of the patient included an aortic valve replacement in 1972 (DeBakey Surgitool aortic valve prosthesis), an AV-Block I as well as a newly diagnosed combined mitral failure.
Her blood pressure was 110/70 mmHg; heart rate, 75 beats/min and regular; and temperature, 37.2 °C. Cardiac auscultation revealed a grade 3/6 systolic murmur that was audible at the apex and a prosthetic click. Her lungs were clear on auscultation. Chest X-ray showed an enlarged configuration of the heart as well as the implanted prosthesis in aortic position (Fig. 1). Current status of her hepatitis C chronic infection was assessed by reverse transcription-polymerase chain reaction (RT-PCR), revealing a serum HCV-RNA above 1500 kIU/ml.
The preoperative diagnostic procedures included a heart angiography and transthoracic echocardiographical analysis. Angiographic analysis revealed a light reduced left ventricular function and no signs of coronary stenoses. Transthoracic echocardiography, including Doppler flow mapping, showed a severe mitral regurgitation, dilatation of the left atrium without presence of thrombus as well as moderate tricuspid regurgitation. It also showed a normally functioning DeBakey Surgitool aortic valve prosthesis. The mean aortic pressure gradient across the Surgitool aortic valve was 20 mmHg and no valve insufficiency or periprosthetic leak was detected. Real time 3-D transthoracic echocardiography was performed, showing a normal function of the prosthetic ball and no deformation of the cage struts (Fig. 2). Mitral valve replacement was scheduled on the basis of these findings.
The operation was performed through a median sternotomy. After preparation of the anatomical structures, both caval veins as well as the ascending aorta were cannulated to establish the cardiopulmonary bypass. The mitral valve was replaced by means of a trans-septal approach with a 29-mm Carpentier-Edwards Perimount Magna bioprosthesis (Edwards Lifesciences, Saint-Prex, Switzerland). The mitral valve replacement was performed with a bioprosthesis in order to reduce the anticoagulation's range from 2.5–3.5 INR values to 2–3 INR values. The aortic valve prosthesis was intraoperatively inspected. The mechanical function was assessed as correct and no increased wearing signs were detected. Due to these reasons the mechanical valve prosthesis was not replaced. The patient recovered uneventfully and was discharged 2 weeks after the procedure. Anticoagulation with an INR between 2.0 and 3.0 was instituted. Good function of both prostheses was confirmed in the early postoperative period and in a 3-month follow-up.
3. Discussion
The DeBakey Surgitool aortic valve prosthesis was introduced in the market in 1967 and became an alternative to the previously commercialised Starr-Edwards ball valve prosthesis (S-E). Both valves presented a similar design consisting of a caged ball, a cloth-covered ring and a cage from bare metal struts. The DeBakey Surgitool prosthesis presented several modifications in comparison to the original S-E prosthesis, presenting a ball made of pyrolitic carbon and a bare metal cage instead of a cloth-covered one. This valve was the first mechanical valve in which pyrolitic carbon was used, an alloy known for its durability and biocompatibility [4,5]. The bare metal ring was designed to reduce the complication rates attached to the cloth-covered ring of the S-E prosthesis, including haemolysis or thromboembolic phenomena related to cloth wear and foreign-body derived complications [6].
Due to demonstrated strut fractures in three cases of mechanical failure of the DeBakey Surgitool aortic valve prosthesis, it was withdrawn from the market in 1978. It was postulated that these fractures had an origin in the different hardness of the involved materials, as well as a weak junction between the cage and the ring which led to stress strut fractures. In the absence of mechanical dysfunction due to strut fractures, DeBakey Surgitool aortic valve prosthesis has been reported as an example of durability of mechanical valves and its prophylactic replacement has not been recommended [7,8]. In our patient, a good mechanical function was pre- and postoperative echocardiographically assessed. Intraoperative inspection evaluation of the DeBakey Surgitool aortic valve prosthesis revealed no increased wearing signs. Due to these reasons, and in consonance with the current literature, we decided not to replace prophylactically the aortic valve.
References
DeWall RA, Qasim N, Carr L. Evolution of mechanical heart valves. Ann Thorac Surg 2000; 69:1612–1621.
Scott SM, Sethi GK, Bridgman AH, Takaro T. Experience with the DeBakey-Surgitool aortic prosthetic valve. Ann Thorac Surg 1976; 21:483–486.
Urgent Device Recall Letter Travenol Laboratories Inc. May 22, 1978;.
Schoen FJ, Titus JL, Lawrie GM. Durability of pyrolytic carbon-containing heart valve prostheses. J Biomed Mater Res 1982; 16:559–570.
Bokros JC, Gott VL, La Grange LD, Fadall AM, Vos KD, Ramos MD. Correlations between blood compatibility and heparin adsorptivity for an impermeable isotropic pyrolytic carbon. J Biomed Mater Res 1969; 3:497–528.
Angelini GD, Kulatilake EN, Armistead SH. Right coronary artery occlusion by cloth from a Starr-Edwards aortic valve prosthesis. Thorac Cardivasc Surg 1984; 32:379–380.
Butany J, Naseemuddin A, Nair V, Feindel CM. DeBakey Surgitool mechanical heart valve prosthesis, explanted at 32 years. Cardiovasc Pathol 2004; 13:345–346.
Von Der Emde JJ, Eberlein U, Breme JJ. Asymptomatic strut fracture in DeBakey-Surgitool aortic valves: incidence, management, and metallurgic aspects. Tex Heart Inst J 1990; 17:223–227.(Andres Beiras-Fernandez, )