Cardiac crossroads: deciding between mechanical or bioprosthetic heart valve replacement

Abstract

Nearly 15 million people in the United States suffer from either aortic or mitral valvular disease. For patients with severe and symptomatic valvular heart disease, valve replacement surgery improves morbidity and mortality outcomes. In 2009, 90,000 valve replacement surgeries were performed in the United States. This review evaluates the advantages and disadvantages of mechanical and bioprosthetic prosthetic heart valves as well as the factors for consideration in deciding the appropriate valve type for an individual patient. Although many caveats exist, the general recommendation is for patients younger than 60 to 65 years to receive mechanical valves due to the valve's longer durability and for patients older than 60 to 65 years to receive a bioprosthetic valve to avoid complications with anticoagulants. Situations that warrant special consideration include patient co-morbidities, the need for anticoagulation, and the potential for pregnancy. Once these characteristics have been considered, patients' values, anxieties, and expectations for their lifestyle and quality of life should be incorporated into final valve selection. Decision aids can be useful in integrating preferences in the valve decision. Finally, future directions in valve technology, anticoagulation, and medical decision-making are discussed.

Keywords: anticoagulant; patient preference; prosthetic heart valves; structural valve deterioration; valve type.

Figure 1

Photographs of commonly used prosthetic valves. Left: single-tilting-disk (Medtronic-Hall, Medtronic, Minneapolis, MN) valve; Right: bileaflet-tilting-disk (St Jude Medical, Little Canada, MN) valve. Notes: Copyright © 1996. Massachusetts Medical Society. Reprinted with permission from Vongpatanasin W, Hillis LD, Lange RA. Medical progress: prosthetic heart valves. N Engl J Med. 1996;335:407–416.

Figure 2

Two-way sensitivity analysis of the effects of anticoagulant-related bleeding and patient age at implantation on the recommended valve type. Notes: RR = relative risk where RR = 1 is the baseline estimate, RR = 1.5 is 50% higher than the baseline estimate, and RR = 0.5 is 50% lower than the baseline estimate. Copyright © 2000. Elsevier. Reprinted with permission from Birkmeyer NJ, Birkmeyer JD, Tosteson AN, et al. Prosthetic valve type for patients undergoing aortic valve replacement: a decision analysis. Ann Thorac Surg. 2000;70:1946–1952.

Figure 3

Photograph of Porcine (Carpentier–Edwards) Bioprosthesis. Notes: Copyright © 1996. Massachusetts Medical Society. Reprinted with permission from Vongpatanasin W, Hillis LD, Lange RA. Medical progress: prosthetic heart valves. N Engl J Med. 1996;335:407–416.

Figure 4

Two-way sensitivity analysis of the effects of reoperation for tissue valve failure and patient age at implantation on the recommended valve type. Notes: RR = relative risk where RR = 1 is the baseline estimate, RR = 1.5 is 50% higher than the baseline estimate, and RR = 0.5 is 50% lower than the baseline estimate. Copyright © 2000. Elsevier. Reprinted with permission from Birkmeyer NJ, Birkmeyer JD, Tosteson AN, et al. Prosthetic valve type for patients undergoing aortic valve replacement: a decision analysis. Ann Thorac Surg. 2000;70:1946–1952.

Figure 5

Two-way sensitivity analysis of the effects of mortality with reoperation and patient age at implantation on the recommended valve type. Notes: RR = relative risk where RR = 1 is the baseline estimate, RR = 1.5 is 50% higher than the baseline estimate, and RR = 0.5 is 50% lower than the baseline estimate. Copyright © 2000. Elsevier, Reprinted with permission from Birkmeyer NJ, Birkmeyer JD, Tosteson AN, et al. Prosthetic valve type for patients undergoing aortic valve replacement: a decision analysis. Ann Thorac Surg. 2000;70:1946–1952.

Figure 6

Algorithm for choice of prosthetic heart valve. Notes: Copyright © 2010. Elsevier. Reprinted with permission from Rahimtoola SH. Choice of prosthetic heart valve in adults: an update. J Am Coll Cardiol. 2010;55: 2413–2426. Abbreviations: A/C, anticoagulants; AVR, aortic valve replacements; INR, international normalized ratio; MVR, mitral valve replacements.

Figure 7

Schematic of decision model structure. All patients are initially in the event-free state. With each 1-year cycle of the model, they can move to a different state or remain in the same state according to chance events specified under “Chance events each cycle”. Notes: Event-free: alive without reoperation or major bleeding; Alive following reoperation: alive following reoperation for prosthetic valve failure; Alive following bleeding: alive following a major (requiring hospitalization or blood transfusion) bleeding event; Dead: dead from any cause. Copyright © 2000. Elsevier. Reprinted with permission from Birkmeyer NJ, Birkmeyer JD, Tosteson AN, et al. Prosthetic valve type for patients undergoing aortic valve replacement: a decision analysis. Ann Thorac Surg. 2000;70:1946–1952.