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Hancock Aortic Tissue Valve
TypeMedical Devices
InventorWarren Hancock, Thomas J. Fogarty
Inception1983
ManufacturerHancock Jaffe Laboratories, Johnson & Johnson
AvailableNo
Current supplierMedtronic
Last production year1999
Models madeT505, T510
Websitehttps://www.medtronic.com/us-en/healthcare-professionals/products/cardiovascular/heart-valves-surgical/hancock-ii-hancock-ii-ultra-bioprostheses.html

The Hancock Aortic Tissue Valve is a prosthetic heart valve used in cardiac surgery to replace a damaged or diseased aortic valve.[1] It is a bioprosthetic valve, meaning it is constructed using biological tissues, specifically porcine (pig) valve tissue.[2] This valve is widely utilized in the field of cardiovascular surgery to restore proper blood flow through the heart.[3]

Development and History

The Hancock Aortic Tissue Valve was invented by Warren Hancock.[4] In the late 1960s and early 1970s, Warren Hancock, an American engineer, collaborated with the medical community to develop a cutting-edge bioprosthetic heart valve. The valve was first introduced by the American company Medtronic.[1] The design of the Hancock valve is based on the concept of xenografts, utilizing pig tissue due to its structural similarities to human heart valves.[5]

Composition

The Hancock Aortic Tissue Valve is composed of porcine valve tissue mounted within a supporting stent frame.[6] The valve is sewn into a fabric-covered sewing ring, facilitating secure attachment within the patient's aortic annulus during the implantation procedure. The design aims to closely mimic the natural function of the human aortic valve, allowing for efficient blood flow and minimizing the risk of complications.[2]

Applications

The Hancock Aortic Tissue Valve is commonly used in patients requiring aortic valve replacement due to conditions such as aortic stenosis or aortic regurgitation.[7] The choice between a mechanical or bioprosthetic valve depends on various factors, including the patient's age, lifestyle, and medical history.[8]

Advantages

  1. Biocompatibility: The use of porcine tissue enhances the biocompatibility of the valve, reducing the risk of adverse reactions and promoting tissue integration.[9]
  2. Durability: The Hancock valve is designed to withstand the rigors of the cardiovascular system, providing long-term durability and reliability.[10]
  3. Hemodynamic Performance: The valve's design allows for optimal blood flow, minimizing turbulence and pressure gradients, which is essential for maintaining cardiac function.[11]
  4. Reduced Anticoagulation Requirement: Unlike mechanical valves, bioprosthetic valves like the Hancock Aortic Tissue Valve may reduce the need for lifelong anticoagulation therapy in some patients.[12]

Disadvantages

Prosthetic heart valves, including the Hancock Aortic Tissue Valve, are not without drawbacks. Structural degradation is a risk, potentially necessitating reoperation.[13][3] Studies have indicated the need for ongoing research and improvement in bioprosthetic valve technology to address such concerns[13]

Procedure

The implantation of the Hancock Aortic Tissue Valve typically involves open-heart surgery.[14] During the procedure, the damaged or diseased native aortic valve is removed, and the prosthetic valve is sutured in its place. The secure attachment of the valve is crucial to ensure proper functionality and prevent complications such as leakage.

References

  1. ^ a b Medtronic. "Hancock II and Hancock II Ultra Bioprostheses - Surgical Heart Valves". www.medtronic.com. Retrieved 2024-01-05.
  2. ^ a b David, Tirone E.; Armstrong, Susan; Maganti, Manjula (September 2010). "Hancock II bioprosthesis for aortic valve replacement: the gold standard of bioprosthetic valves durability?". The Annals of Thoracic Surgery. 90 (3): 775–781. doi:10.1016/j.athoracsur.2010.05.034. ISSN 1552-6259. PMID 20732495.
  3. ^ a b Valfrè, Carlo; Ius, Paolo; et al. (2010). "The fate of Hancock II porcine valve recipients 25 years after implant". European Journal of Cardio-Thoracic Surgery. 38 (2): 141–146. doi:10.1016/j.ejcts.2010.01.046. PMID 20194029.
  4. ^ Buch, Wally S.; Pipkin, Robert D.; Hancock, Warren D.; Fogarty, Thomas J. (1975-11-01). "Mitral Valve Replacement With the Hancock Stabilized Glutaraldehyde Valve: Clinical and Laboratory Evaluation". Archives of Surgery. 110 (11): 1408–1415. doi:10.1001/archsurg.1975.01360170148023. ISSN 0004-0010. PMID 811195.
  5. ^ US3570014A, Hancock, Warren D., "Stent for heart valve", issued 1971-03-16 
  6. ^ "The Mosaic Mitral Valve Bioprosthesis: A Long-Term Clinical and Hemodynamic Follow-Up". meridian.allenpress.com. Retrieved 2024-01-05.
  7. ^ Cohen, L. H.; Koster, J. K.; Mee, R. B.; Collins, J. J. (August 1979). "Long-term follow-up of the Hancock bioprosthetic heart valve: a 6-year review". Circulation. 60 (2 Pt 2): 87–92. doi:10.1161/01.cir.60.2.87. ISSN 0009-7322. PMID 376181. S2CID 39382249.
  8. ^ Rizzoli, Giulio; Bottio, Tomaso; Thiene, Gaetano; Toscano, Giuseppe; Casarotto, Dino (July 2003). "Long-term durability of the Hancock II porcine bioprosthesis". The Journal of Thoracic and Cardiovascular Surgery. 126 (1): 66–74. doi:10.1016/s0022-5223(02)73618-0. ISSN 0022-5223. PMID 12878940.
  9. ^ Dasi, Lakshmi P; Simon, Helene A; Sucosky, Philippe; Yoganathan, Ajit P (February 2009). "Fluid Mechanics of Artificial Heart Valves". Clinical and Experimental Pharmacology & Physiology. 36 (2): 225–237. doi:10.1111/j.1440-1681.2008.05099.x. ISSN 0305-1870. PMC 2752693. PMID 19220329.
  10. ^ Anderson, Lindsey; Taylor, Rod S (2014-12-12). "Cardiac rehabilitation for people with heart disease: an overview of Cochrane systematic reviews". The Cochrane Database of Systematic Reviews. 2014 (12): CD011273. doi:10.1002/14651858.CD011273.pub2. ISSN 1469-493X. PMC 7087435. PMID 25503364.
  11. ^ Dasi, Lakshmi P; Simon, Helene A; Sucosky, Philippe; Yoganathan, Ajit P (February 2009). "Fluid Mechanics of Artificial Heart Valves". Clinical and Experimental Pharmacology & Physiology. 36 (2): 225–237. doi:10.1111/j.1440-1681.2008.05099.x. ISSN 0305-1870. PMC 2752693. PMID 19220329.
  12. ^ Choudhary, Shiv Kumar; Talwar, Sachin; Airan, Balram (2016-04-28). "Choice of prosthetic heart valve in a developing country". Heart Asia. 8 (1): 65–72. doi:10.1136/heartasia-2015-010650. ISSN 1759-1104. PMC 4898620. PMID 27326237.
  13. ^ a b Head, Stuart J.; Çelik, Mevlüt; Kappetein, A. Pieter (2017-07-21). "Mechanical versus bioprosthetic aortic valve replacement". European Heart Journal. 38 (28): 2183–2191. doi:10.1093/eurheartj/ehx141. ISSN 0195-668X. PMID 28444168.
  14. ^ "Hancock Aortic Tissue Valve". americanhistory.si.edu. Retrieved 2024-01-05.
source: https://en.wikipedia.org/wiki/Warren_Hancock

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