Download presentation
Presentation is loading. Please wait.
Published byJada Plimpton Modified over 10 years ago
2
Edward Evans MD FACC Desoto Heart Clinic Disclosures Medtronic:speaker St. Jude Medical:speaker
3
Valvular Surgery YearSurgeonDescription 1960Dwight Harken1 st successful aortic valve replacement (AVR). A caged ball valve was used 1960Starr and Edwards 1 st successful mitral valve replacement (MVR) using caged-ball valve of their own design. 1960-67Approx. 2000 Starr-Edwards valves implanted 1962HeimbeckerToronto. 1 st clinical implant of an aortic hemograft valve. 1962Daniel Ross1 st successful aortic valve homograft implant 1964Duran and Gunning Aortic valve replacement with xenograft porcine aorti valve (formaldehyde-fixed xenografts->tissue degradation and calcification). 1971CarpentierXenograft valves fixed with glutaraldehyde and mounted on a stent to produce a bioprosthesis
4
4 1858 - Improved bottle stopper conceptual impetus for the first successful ball and cage design
5
5 1960s - Commercially Available Valves Caged-ball valves were improved and became commercially available 1960: Harken implanted a double-cage ball valve into aortic annulus 1960: first implant of the Starr-Edwards valve - mitral position (first sold in 1965)
6
Prosthetic Heart Valve Management
7
Post-operative surveillance Prevention of infection Prevention of thrombosis Management of complications
8
Surveillance Initial post-op visit: – H&P, CXR, EKG –class 1 – 2D echo – class 1 if unsatisfactory…other studies – Labs: CBC, INR
9
Surveillance Later visits: (patients without complications) – Routine follow-up yearly. Earlier if clinical changeClass I – Routine serial echoClass IIb Echo if change in exam New regurgitationecho every 3-6 months.
10
Prevention of Infection Class I – 2% risk of infection at 14 days with no prophylaxis. Dental procedures Invasive Respiratory procedures with incision or biopsy Surgery involving infected skin or musculoskeletal tissue
11
Prevention of Infection 30-60 min before procedure Amoxicillin 2g PO/Ampicillin 2g IV/IM Cephalexin 2g PO Azithromycin 500mg PO Clindamycin 600mg PO or IV Cefaxolin or Ceftriaxone 1g IV/IM
12
Anticoagulation Mechanical valves: – Risk of thromboembolic event Untreated: up to 8% per year Treated: less than 2% per year – Mitral greater risk than aortic – Higher risk early post-operatively Bioprosthetic valves: – 0.7% per year risk
13
Anticoagulation All valves require anticoagulation – Duration – Agent(s) Valve type and position Patient risk factors – Atrial fibrillation – Previous thromboembolic event – Hypercoagulable state – Low EF < 30% Contraindications
14
Anticoagulatioin Aspirin 75-100mg daily – All patients – class 1 – Use alone with bioprosthetic AVR and MVR with no risk factors Coumadin (INR 2.0-3.0) – Mechanical AVR bileaflet, no risk factors – Bioprosthetic First 3 months – class 2a Long term with risk factors.
15
Anticoagulation Coumadin (INR 2.5-3.5) – All others Starr-Edwards run higher >3.0
16
Anticoagulation Events while at target: – INR 2-3: increase to 2.5 to 3.5 – INR 2.5-3.5: increase to 3.5 to 4.5 Short term interruption: – Bileaflet AVR no risk factors: No bridge – Bridge all others with UFH – LMWH is class 2b – FFP in emergencies – No vitamin K
17
Complications Structural valve deterioration Non-structural Valve Dysfunction Thrombosis and Embolism Valvular endocarditis Hemolysis
18
Structural Valve Dysfunction
19
Structural Valve Dysfunction Mechanical Primary failures rare now. Led to discontinuation of certain valves Now mainly valve ring-tissue interface Mechanisms: – Valve dehiscence – Perivalvular regurgitation – Tissue in growth (pannus) and thrombosis
20
Structural Valve Dysfunction Bioprosthetic Incidence 20-30% at 10 years, 50% at 15 years Tissue degeneration Secondary calcification – Stenosis increasing after 6 years – More likely with MVR, youth, pregnancy, and chronic renal failure Perforation Perivalvular regurgitation
21
Nonstructural Valve Dysfunction Clinically significant obstruction in the setting of normal prosthetic function Patient prosthetic mismatch Occurs mostly in older women Thrombus and Pannus
22
SEVERE MODERATE MILD/NONE (non significant) 0.65 0.85 Indexed EOA (cm 2 /m 2 )
23
LVEF 40% 3% 5% P=0.0 8 23% P<0.00 1 7%P=0.05 16% 67%P<0.001 Short-Term Mortality Short-Term Mortality (%) (%) LVEF < 40% Combined Impact of PPM and LV Dysfunction on Short-term Mortality
24
Thrombosis and Embolism Incidence 0.6% to 2.3% per patient year – Anticoagulated mechanical rate same as unanticoagulated bioprosthetic – Mitral position greater risk than aortic – Tricuspid greatest risk Intrinsic thrombogenicity of valve materials, flow turbulence and stagnation, shear stresses, risk factors
25
Valve thrombosis Echo, TEE, Fluoroscopy, MRI/CT Thrombolysis – 70-90% effective – Mortality 4-12% acutely – Better for right sided valves – Duration < 24hours Surgery – Class 2a for large clot, NYHA 3-4 – Class 1 small clot, failure or contraindications to lysis
26
Embolism Mechanical valves – No anticoagulation: 4% per year – Aspirin: 2% per year – Coumadin (therapeutic) 1% per year – Mitral valves twice the risk of aortic valves
27
Prosthetic valve endocarditis Yearly risk 0.5% despite prophylaxis Highest risk MVR No difference mechanical and bioprosthetic Risk greatest in first 6 months Usually involves the valve ring Substantial mortality
28
Prosthetic Valve Endocarditis Medical – Hospitalize at CV surgery center – Delay antibiotics until organism identified – TEE – Prolonged antibiotics with ID guidance Surgery – Heart failure, abscess, dehiscence, relapsing infection, failed antibiotic
30
Macroangiopathic hemolytic anemia Anemia post operatively – Microcytic – Increased LDH – Decreased haptoglobin – NO suspicion of ITP/TTP – Schistocytes May lead to heart failure Transfusion dependent anemia Potential need for re-do valve surgery
31
Summary Prosthetic valves are not a cure for valvular disease Associated with large number of potential medical management issues Careful post-operative valvular surveillance is important
32
Questions?
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.