Valve selection

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Valve selection

• Weerachai Nawarawong M.D.

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Mechanical valve advantage

• Children
• Patients lt40 yrs
• High reoperation risk
• Small annular size
• Atrial fibrillation
• Pregnancy desired
• Patients gt 70 yrs
• High thromboembolism risk
• High hemorrhage risk

Tissue valve advantage
Akins CW Ann Thorac Surg 1991,52161-172
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Which valve ?
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• If one can choose the valve prosthesis one would
  choose
• One valve for life

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Myths about Mechanical Valves

• Youll Never Need Another Operation
• You can Live without Restrictions
• Risks of TE/ACH are Minimal
• Coumadin is Not a Problem

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Nine Commandmentsfor prosthetic valve

• Embolism Prevention
• Durability
• Ease and Security of Attachment
• Preservation of Surrounding Tissue Function
• Reduction of Turbulance
• Reduction of Blood Trauma
• Reduction of Noise
• Use of Materials Compatible with Blood
• Development of Methods of Storage and
  Sterilization

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Ideal valve

• Good hemodynamic
• Quiet
• Require no anticoagulation
• Last for life time
• Cheap
• Easy to implant

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Valve Prosthesis

• Mechanical
• types caged-ball, tilting-disk, bi-leaflet
• advantage durability
• limitation thrombogenicity
• Bioprosthetic
• types heterografts, homografts
• advantage short term anticoagulation
• limitation structural failure
• leaflet calcification tissue degeneration
  leading to valvular regurgitation
• rate of porcine valve degeneration 26 (aortic),
  39 (mitral) in 10 yrs

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Homografts

• 1956 - first aortic valve homograft was used in
  the descending thoracic aorta for aortic
  regurgitation
• 1962 - first sub-coronary use
• high incidence of post-op failure
• (years) 5 10 15 20
• survival rate () 85 66 53 38
• re-operation () 22 62 85 95

Circulation 1991 84(suppl 3)III81-III88
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Durability and hemodynamic
Bleeding and thromboembolism
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Thromboembolism and Bleeding
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Wall Street Journal 8//16//07

• Warfarin is the second-most-likely drug, after
  insulin, to send Americans to the emergency
  room.
• By one estimate, it accounts for 43,000 ER visits
  a year in the U.S.

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• Van der Meer
• 42 more major bleeding complications for every
  one-point increase in INR.
• The incidence from major bleeding complications
  given in the literature varies between 1.6 and
  5.2 increasing with age

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Incidence of major embolismafter mechanical
valve replacement

• Absence of antithrombotic therapy
• 4 per year
• plus 1.8 per year risk of valve thrombosis
• Antiplatelet therapy
• 2.2 per year
• plus 1.6 per year risk of valve thrombosis
• Wafarin therapy
• 1 per year
• 0.8 per year with an aortic valve
• 1.3 per year with a mitral valve
• plus 0.2 per year risk of valve thrombosis
• Incidence of major bleeding in patients treated
  with warfarin
• 1.4 per 100 patient-years.

(Circulation. 199489635-641.)
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Incidence Rates of Valve Thrombosis and Major and
Total Embolisms Effect of Antithrombotic
Treatment Incidence Rates per 100
Patient-Years (95 Confidence Intervals) Anticoag
ulation Valve Thrombosis Major Embolism Total
Embollsm None 1.8 (0.9-3.0) 4.0 (2.9-5.2)
8.6 (7.0-10.4) Antiplatelet 1.6 (1.0-2.5) 2.2
(1.4-3.1) 8.2 (6.6-10.0) Dipyridamole 4.1
(1.9-7.2) 5.4 (2.8-8.8) 11.2 (7.3-15.9) Aspirin
1.0 (0.4-1.7) 1.4 (0.8-2.3) 7.5
(5.9-9.4) Coumadin 0.2 (0.2-0.2) 1.0 (1.0-1.1)
1.8 (1.7-1.9) Coumadin and antiplatelet 0.1
(0.0-0.3) 1.7 (1.1-2.3) 3.2 (2.4-4.1)
(Circulation. 199489635-641.)
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Incidence Rates of Valve Thrombosis and Major and
Total Embolisms With Coumadin Therapy Effect of
Valve Position Incidence Rates per 100
Patient-Years (95 Confidence Intervals) Valve
Position Valve Thrombosis Major Embolism
Total Embolism Aortic 0.1 (0.1-0.2) 0.8
(0.7-0.9) 1.1 (1.0-1.3) Mitral 0.5 (0.3-0.7)
1.3 (1.1-1.5) 2.7 (2.3-3.0) Both 0.4
(0.2-0.7) 1.4 (1.0-1.9) 2.1 (1.6-2.7)
(Circulation. 199489635-641.)
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Types of prosthetic valves and thrombogenicity Ty
pe of valve Model Thrombogenicity Mechanical
Caged ball StarrEdwards Single
tilting disc BjorkShiley, Medtronic
Hall Bileaflet St Jude
Medical, Sorin Bicarbon, Carbomedics
Bioprosthetic Heterografts CarpentierEdwards
, Tissue Med (Aspire), Hancock II to
Homografts
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• Mitral heart valve prostheses carry a risk of
  embolism that is almost twice as high as aortic
  valve prostheses
• Cannegieter SC, Rosendaal FR, Briet E (1994)
  Thromboembolic and bleeding complications in
  patients with mechanical heart valve prostheses.
  Circulation 89 635641

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Zellner et al Long term experience With the
St.Jude Medical Valve Prosthesis South
Carolina,USA AVR 418 pts,
mean age 54.8yrs Re-operation inc. 1.0/pt/y
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Hemodynamic advantages
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Gradient
Comparison of mean pressure gradients for    
commonly implanted prosthetic valves.
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EOA
Comparison of EOAs for commonly implanted    
prosthetic valves.
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Patient prosthesis mismatch
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• There are trends in the United States and Europe
  toward the increasing use of tissue rather than
  mechanical valves and toward the use of
  bioprostheses in progressively younger patients
• Dagenais F, Cartier P, Voisine P, Desaulniers D,
  Perron J, Maillot R, Raymond G, Métras J, Doyle
  D, Mathieu P. Which biologic valve should we
  select for the 45- to 65-year-old age group
  requiring aortic valve replacement? J Thorac
  Cardiovasc Surg. 200512910411049.

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Reasons for increasing use of Bioprosthesis

• Newer generation bioprosthesis are more durable
  and better.
• Reoperation rates for patients over 65 years of
  age are particularly low with modern stented
  bioprostheses
• The risks of reoperation have continued to
  decrease
• Patients undergoing AVR today are older
  population than those studied in the randomized
  trials.
• Young patients undergoing aortic valve surgery
  are often reluctant to accept warfarin therapy
  and the activity constraints associated with
  anticoagulants.
• There are some nonrandomized but relatively large
  comparative trials that have shown apparent
  survival benefit for patients receiving
  bioprostheses, particularly for those over the
  age of 65 years .

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Why bioprosthesis

• Better fixation technique
• Better anticalcification technique
• Better long term result in newer generation valve
  
• Better surgical technique , redo less dangerous

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Durability
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• Two historic randomized clinical trials compared
  outcomes after valve replacement with a
  first-generation porcine heterograft and the
  original Bjork-Shiley tilting-disc mechanical
  valve
• The Edinburgh Heart Valve Trial, conducted
  between 1975 and 1979 with an average follow-up
  of 12 years,
• The Veteran Affairs (VA) Cooperative Study on
  Valvular Heart Disease, conducted between 1979
  and 1982 with an average follow-up of 15 years.

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• The Edinburgh trial
• a small survival advantage associated with a
  mechanical valve in the aortic but not in the
  mitral position
• both trials showed
• increased bleeding associated with mechanical
  valves
• increased reoperation with tissue valves
• structural failure of tissue valves and overall
  thromboembolic complications were greater after
  mitral than after aortic valve replacement.

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• A meta-analysis of 32 articles evaluated
  mortality from 15 mechanical and 23 biological
  valve series including 17,439 patients and 101,
  819 patient-years of follow-up.
• no difference in riskcorrected mortality between
  mechanical and bioprosthetic aortic valves
  regardless of patient age
• choice between a tissue and mechanical valve
  should not be based on age alone.
• Lund O, Bland M. Risk-corrected impact of
  mechanical versus bioprosthetic valves on
  long-term mortality after aortic valve
  replacement. J Thorac Cardiovasc Surg.
  200613220 26.

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• Retrospective study comparing mechanical and
  tissue aortic valve replacement in 3062 patients
  with combined follow-up of 22 182 patientyears
• age but not valve type was predictive of
  valve-related mortality.
• reoperation was higher after tissue aortic valve
  replacement only for patients 60 years of age,
• combined valverelated morbidity was higher after
  mechanical valve replacement for all patients 40
  years of age.
• Chan V, Jamieson WRE, Germann E, Chan F,
  Miyagishima RT, Burr LH, Janusz MT, Ling H,
  Fradet GJ. Performance of bioprostheses and
  mechanical prostheses assessed by composite of
  valve-related complications to 15 years after
  aortic valve replacement. J Thorac Cardiovasc
  Surg. 200613112671273.

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• Advances in tissue fixation and anticalcification
  treatment have resulted in current-generation
  bioprostheses that have superior durability

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Freedom from structural valve deterioration

• Carpentier-Edwards pericardial aortic valve (age
  65)
• 94 at 10 years
• 77 at 15 years
• 10 chance that a 65-year-old patient would
  require reoperation before 80 years of age.
• Third-generation bioprostheses may be even more
  durable, with
• 92.8 at 12 years (mean age of 54 years)
• In addition, advances in myocardial protection
  and cardiac surgical techniques have led to lower
  risks at reoperation, making the prospect of redo
  valve surgery less dangerous.
• Banbury MK, Cosgrove DM III, White JA, Blackstone
  EH, Frater RWM, Okies JE. Age and valve size
  effect on the long-term durability of the
  Carpentier-Edwards aortic pericardial
  bioprosthesis. Ann Thorac Surg. 200172753757.
• Bach DS, Metras J, Doty JR, Yun KL, Dumesnil JG,
  Kon ND. Freedom from structural valve
  deterioration among patients 60 years of age and
  younger undergoing Freestyle aortic valve
  replacement. J Heart Valve Dis. In press.

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Freedom from structural valve deterioration after
15 years

• 2nd generation Hancock II aortic valve
• 81.5 ( age 65 years)
• 1st generation Hancock bioprosthesis.
• 57.4 (age 69 years )
• David TE, Ivanov J, Armstrong S, Feindel CM,
  Cohen G. Late results of heart valve replacement
  with the Hancock II bioprosthesis. J Thorac
  Cardiovasc Surg. 2001121 268278.
• Cohn LH, Collins JJ Jr, Rizzo RJ, Adams DH,
  Couper GS, Aranki SF. Twenty-year follow-up of
  the Hancock modified orifice porcine aortic
  valve. Ann Thorac Surg. 1998 66(suppl)S30 S34.

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Hancock Valve Durability Data
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ACC/AHA VHD Guidelines 2008
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ACC/AHA VHD Guidelines 2008
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M.OBrien et al The Homograft Aortic Valve29
yrs J. Heart V. Dis 200110334-345 1,022
patients mean age 47yrs Actuarial Survival
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OBrien et al,2001 Aortic Homograft Durability vs
Age Freedom from Re-op
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Reasons for tissue valve

• Expected life expectancy lt 10-12 yrs
• Anticoagulation contraindicated.
• Patient cannot or will not take anticoagulant.
• Patient at increased risk for bleeding with
  anticoagulation.
• INR difficult to control
• Poor compliance
• Difficult follow up

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The main indication for re-operation of mitral
valve prostheses

• Structural deterioration of (tissue) valves,
• Endocarditis,
• Para- valvular defects,
• Valve thrombosis,
• Pannus formation
• Residual or recurrent tricuspid incompetence.
• Progressive coronary artery disease

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Risk factors for early mortality after reoperation

• Emergency operation for thrombosis of a
  prosthesis,
• Acute endocarditis,
• Acute valvular dehiscence with clinical
  deterioration, and surgical problems.
• Older age and NYHA class also play a major role

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Reoperation

• Single mitral valve re-replacement
• elective
• normal left and right ventricular function
• risk 1.5 .
• The peri-operative mortality with
• emergency operation up to 40,
• double valve replacement to 22,
• with poorer NYHA class, (from 2.2 to 15.5),
• concomitant procedures to 16

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50-year-old man with no comorbidities undergoing
aortic valve replacement
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Mechanical aortic valve replacement

• Anticipated, operative mortality is 1.5
  EuroSCORE regardless of the prosthesis implanted.
  
• After mechanical valve replacement,
• 0.3/y chance of reoperation,yielding a 9 risk
  of reoperation if the man lives to be 80 years of
  age.
• chance of death at reoperation is 24,assuming
  that reoperation is done on an emergency basis at
  65 years of age, yielding a 2.1 chance of death
  at reoperation.
• Valve-related mortality is
• 0.5/y for a patient 51 to 60 years of age
• 1.1/y in patients 61 years of age,
• yielding a cumulative risk of valverelated
  mortality of 27 over 30 years (10 0.5)(20
  1.1).
• Valve-related morbidity
• 2.2/y for a patient 51 to 60 years of age,
• 2.7/y for a patient 61 to 70 years of age,
• 2.9/y for a patient 71 years of age,
• yielding a cumulative risk of valve-related
  morbidity of 78 over 30 years, (10 2.2)(10
  2.7) (10 2.9),
• Cumulative 108.6 risk of valve-related morbidity
  or mortality (30.6 mortality78 morbidity) over
  30 years.
• Chan V, Jamieson WRE, Germann E, Chan F,
  Miyagishima RT, Burr LH, Janusz MT, Ling H,
  Fradet GJ. Performance of bioprostheses and
  mechanical prostheses assessed by composite of
  valve-related complications to 15 years after
  aortic valve replacement. J Thorac Cardiovasc
  Surg. 2006131 12671273.
• Roques F, Michel P, Gladstone AR, Nashef SAM. The
  logistic EuroSCORE. Eur Heart J. 20032412.

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Bioprosthesis valve replacement

• At least 1 anticipated reoperation before 80
  years of age. If reoperation occurs at 65 years
  of age (15 years after initial surgery),
  operative risk is 5.8,assuming that surgery is
  done electively.
• The anticipated risk of valve-related mortality
  after bioprosthetic valve replacement is
• 0.6/y for a patient 51 to 60 years of age,
• 1.0/y for a patient 61 to 70 years of age,
• 1.3/y for a patient 71 years of age,
• yielding a cumulative risk of valve-related
  mortality of 29 over 30 years (10 0.6)(10
  1.0)(10 1.3), similar to that after mechanical
  valve replacement.
• Valve-related morbidity
• 0.3/y for a patient 51 to 60 years of age,
• 0.4/y for a patient 61 to 70 years of age,
• 0.5/y for a patient age 71 years of age,
• yielding a cumulative risk of valve-related
  morbidity of 12 over 30 years(10 0.3)(10 0.4)
  (10 0.5)
• Cumulative 48.3 risk of valve-related morbidity
  or mortality 36.3 mortality12 morbidity over
  30 years.
• Even if the patient required a second
  reoperation, the cumulative risk increases by
  only 10.8 (calculated at 75 years of age).
• Chan V, Jamieson WRE, Germann E, Chan F,
  Miyagishima RT, Burr LH, Janusz MT, Ling H,
  Fradet GJ. Performance of bioprostheses and
  mechanical prostheses assessed by composite of
  valve-related complications to 15 years after
  aortic valve replacement. J Thorac Cardiovasc
  Surg. 2006131 12671273.

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Projected Future Risks After Aortic Valve
Replacement in a 50-Year-Old Man, Assuming
30-Year Survival Mechanical Valve
Bioprosthetic Valve Replacement,
Replacement, Operative mortality 1.5
1.5 Death at reoperation (risk of
reoperationrisk of 2.1 5.8 death at
reoperation) (10.8 for second
reoperation) Valve-related
mortality (cumulative for 30 y) 27
29 Valve-related morbidity (cumulative for 30
y) 78 12 Total risk of morbidity
and 108.6 48.3 mortality over 30 y (59.1
if 2 reoperations)
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Durable valve repair possible
Yes
No
Physician assessment
Life expectancy lt15 yr co morbidity
Life expectancy gt30 yr No co morbidity
Life expectancy 15-30 yr No co morbidity
Accept risk of reoperation No coagulation
Minimal life style change
No reoperation Will take anticoagulation
Accept life style change
Patient preference
Valve repair
Mechanical valve
Tissue valve
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• If the patients characteristics do not sway the
  balance in favor of any particular valve
  substitute,
• The surgeon should use the valve most familiar to
  him.
• No one should test the depth of a river with
  both feet.
• Lawrence Bonchek, M.D

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