Post on 24-Jan-2018
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Prosthetic Heart Valve Obstruction:Thrombolysis or Surgery
Taher Elkady, MD
National Heart Institute
Prosthetic Valve Obstruction PVO
Life threatening
morbidity & mortality
0.1% - 6% per patient year (left)
20% in of tricuspid valve
Thrombus Pannus Vegetation
Predictors of Prosth. Valve Thrombosis PVT
Valve type
Anticoagulation status
Valve position
Atrial fibrillation
Ventricular dysfunction
Inadequate anticoagulant therapy
Pathophysiology
Prosthetic valve thrombosi PVT
Thrombus ++ mechanical valves
Platelet & blood cells
Xx endocardium Surface of the Metabolic/structuralImmed after surgery mechanical valve changes due to irregular flow
At hignes 1st 3 – 6 post implant (10%) ++ Mitral
PVT: Sites
1. Suture sites
2. Prosthesis material
Bioprostheses
PVT is less frequent (0.03% per year)
++ 1st months post-surgery
Endothelization of the sewing ring
Pannus Ingrowths
Fibro C.T. ingrowths
Swing ring
Many years post implant
Aortic position / prost. Ring of mitral repair
Thrombus on a Pannus
Clinical Presentation
OPVT systemic embolization, fatigue, SOB (weeks)
Acute hemodynamic collapse & deathNOPVT
Minimal S & S, stableEmbolic potential
IEC blood culturesP/E
PV sounds, a new murmurChanges of a previous murmur
Diagnosis TTE, TEE, Fluoroscopy, MSCT
Tranthoracic Echo (TTE)
?? Acoustic shadowing
Best for: Transvalvular gradient thrombolysis
Mitral prosthesis
Early peak velocity
Mean PG
DVI, PHT, EOA (continnuty)
TR RVSP/PGT
Aortic prothesis
Peak /PG
DVI, EOA
P.S flow velocity does not reflect PVD
Causes of flow velocity
–PVO
–High-output status
– Severe prosthesis regurgitation
–Patient prosthesis mismatch
TEE, Fluoro, MSCT
Transesophageal Echocardiography TEE
• Thrombus size & location
• D.D. Pannus: thrombus: vegitation
• Mitral & Tricuspide prosthesis
• Aortic bioprosthesis
• Aortic homograft
• Other causes of prosthesis obstruction
• Small thrombus vs. prosthesis filaments (fibrin)
++ in AA & AV replacement
TEE in PVO
Pannus Thrombus
Size smaller larger
Echogenicity echodense echosoft (lucent) = myocardium
Valve mechanism - no effect block all valve
- valve stifening mechanisme
- xx valve closure /opening
TEE: PVOThombus size Treatment strategy
ThrombolysisTEE (+ Doppler)
Serial hemodynamic success of fibrinolysis
Tong, Rondaut et al. JACC 2004(Pro – TEE registry)
Left –sided OPVT:Thrombus Area <0.85 cm
Risk for embolism/death with thrombolysis
Other causes of PVO
• Mitral chordal remnants
• Longer sutures
• Unraveled sutures
• LVOTO with AML retention in MV repair
Cinefluoroscopy
Prosthesis valve motion
• Opening and closing angles
• Motion of the base ring of P
• Leaflet motion in mechanical Ao. P
Multidetector cardiac C.T
• Disc mobility = fluoro
• Pannus vs. thrombus ++ in aortic P
• Biological leaflet thickening /restriction
• Serial assessment
Limitations
Atrial fibrillation
SOB / poor functional class
Realtime 3-Dimensional TEE
Enface visualization of P
Promising
++ thrombus/Pannus
PVT: Treatment
• Location
• Size
• Functional class
• Risk of surgery
• Risk of thrombolysis
• experience
Left-sided OPVT
• Emergency Surgery
Valve replacement
Thrombectomy
• Thrombolysis
No RCTs to compare the two methods
Guidelines dilemma:
• Which is the ttt of choice?
• Major determinants of treatment• Functional class
• Thrombus size
• OPVT/NOPVT
Surgery in left sided OPVT
ECS (2007) / ACC-AHA (2008) guidelines
Surgery in the ttt of choice
Operative mortality (5% - 18%) & NYHA class
4-7% in class I-III & 17.5 – 31.3% in class IV
Thrombolysis in Lt. sided OPVT
Earlier studiesThrombolysiis the heparin MR
systemic embolisimbleeding, rethrombosis
Rondaut et al. arch C.V Dise 2009Surgery Thrombolysis
Mortality 10% 10%Hemody. Success 81% 70.9%Embolic episode 0.7% 1%Total complications 11% 25%
Thrombolysis is warranted only as a rescue procedure
Thrombolysis
Hemodyn. Success 64 - 89%Systemic emboli 5 – 19%Major bleeding 5 – 8%Recurrence 15 – 31%Mortality 6 – 12.5%
• Roudant R et al. JACC 2004• Loriga FM et al. J thrombolysis 2006• Nagy A et al. J Heart valve dise. 2009• Keuleers S et al. AJC, 2011
NYHA – IV Mortality: 7% post thromb 17% post surgery
NYHA: I – III Mortality: 5% in both
Thrombus < 14 days higher fibrinolysis chance of success
i.e Chronic thrombosis surgery
(Pannus)
FAQ
Failed thrombolysis? Surgery
Partial success? Surgery
Surgery post thrombolysis when?
• 24 hrs after the discontinuation of the infusion
• 2 hrs after neutralizing fibrinolytic activity by protease inhibition
Thrombolitic agents
Skase, Urokinase, rt-PA
Protocols: as pulmonary thromboimbolism
1. Skase: 250000 I.U/30 min 100000 IU/hr for 72 – 96 hrs2. Urokinase: 4400 U/kg/hr for up to 12 hrs3. Rt-PA: 10 – 15 mg boluses
90 mg 85 mg over 90m – 180 min (total dose 100 mgRecently:
Rt-PA 25 mg bolus slow infusion (over 6 hrs)Lower MR (for bleeding)
Rt. Side PVT
Fibrinolysis of choice
failed
Surgery
Pannus, contraindication to thrombolysis Surgery
Watch: PFO or ASD
Recurrent Episodes of PVT
Surgery of choice
+ Pannus
Fibrinolysis less effective
How to avoid?
Add ASA (I,D) INR
Valve replacement by a bioprosthesis
NOPVT & size – Embolism
• Small < 5mm length, asymptomatic
Medical ttt: anticoagulant Rx, add ASA
• Long thrombus or embolic
Thrombolysis or surgery
Conclusion
• PVT can be a medical emergency with mortality
• TEE plays an important role to diagnosis
• TEE provides incremental information about success of therapy
• Management in design and performance of metallic & bioprosthesis, together within the use of new direct thrombin & Xa inhibitors
New perspectives for the further management of pts with PVT