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