Innovations in Interventional Cardiology Kinepolis - Saturday 12-3-2011

CARDIO 2012

Innovations in Interventional Cardiology E.Benit MD Hasselt Heart Centre Belgium

Percutaneous left atrial appendage closure in atrial fibrillation

Atrial fibrillation Most common sustained cardiac arrhytmia (>6.000.000 patients in Europe) Higher prevalence in the elderly population : prevalence of AF rise from 1% among 55-59 years old patients to > 10% for those older than 80(1). Silent AF is probably as frequent as diagnosed AF

(1) Lloyd-Jones DM et al, Circulation 2004 ; 110: 1042-46

Atrial fibrillation Risk factor for stroke and thrombo-embolism Responsible for 10-15% of all ischemic strokes(1) In Europe, stroke is the third leading cause of death behind heart disease and cancer(2) The most common aetiological factors for AF are hypertension, heart failure, ischaemic heart disease and valvular disease

(1) Hylek E M et al., Stroke 2006 ; 37(4) : 1075-80 (2) World Health Report 2004

The risk of stroke in non-anticoagulated patients increases with age from 1-5% / year in patients age 50-59 years to 23.5% / year in patients aged 80-89 years(1). Silent cerebral infarction may occur in patients with AF in up to 15% of cases(2). 35% of patients with AF will have a stroke in their lifetime(3). (1) Lin H i et al., Stroke 1996 ; 27(10) : 1760-1764 (2) D Holmes, Sem. In Neurology 2010 ; 30-5 : 528-534 (3) Wolf PA et al. Stroke 1991 ; 22: 983-8

In stroke-survivors at 3 months 15-30% are permanently disabled and an additional 20% require institutional care(1) The risk of stroke in patients with AF is increased irrespective of whether the arrhythmia is paroxysmal, persistent or permanent (accepted) (= whether AF is paroxysmal, persistent or permanent should not influence the choice of antithrombotic therapy)(2)

(1) Smith WS et al., Stroke 2005 ; 36(7) : 1432-1438 (2) ESC guidelines atrial fibrillation 2010

What is Atrial Fibrillation ? Sinus Rhythm

Atrial Fibrillation

AF involves the two upper chambers (atria) of the heart. Its name comes from the fibrillating (i.e., quivering) of the heart muscles of the atria, instead of a coordinated contraction

‘Natural’ time course of AF First detected

AF Silent

Paroxysmal

Persistent

Long-Standing Persistent

Permanent time

Patients with paroxysmal AF should be regarded as having a stroke risk similar to those with persistent or permanent AF, in the presence of risk factors” 2,3 = Cardioversion 1 2

3

Adapted from Kirchhof, et al., Outcome parameters for trials in atrial fibrillation; Europace (2007) 9, 1006–1023 Hughes M, Lip GY. Stroke and thromboembolism in AF: a systematic review of stroke risk factors, risk stratification schema and cost effectiveness data. Thromb Haemost 2008;99:295–304. Stroke in AF working group. Independent predictors of stroke in patients with AF: a systematic review. Neurology 2007;69:546–554

0 = low risk : no treatement or Aspirin (no treatment preferred) 1 = intermediate risk : Aspirin or OAC (OAC preferred) ≥ 2 = high risk : OAC

CHADS2 score and stroke rate

Cha2ds2-vasc (stroke and thromboembolism risk) and Hasbled score (bleeding risk) in nonvalvular AF patients

Cha2ds2-vasc score 0 = truly low risk patient : no antithrombotic treatment Cha2ds2-vasc score 1 = intermediate risk : OAC or Aspirin (preferred : AOC rather than Aspirin) Cha2ds2-vasc score 2-9 = high risk : OAC


Exept for males who are < 65 years and have no risk factors, all AF patients should receive oral anticoagulation if absence of contraindications.

Adjusted stroke rate according to CHA2DS2-VASc score

IF HIGH CHA2DS2-VASC SCORE : MORE STROKES BUT ALSO MORE BLEEDING EVENTS !


Optimum selection of patients with AF for anticoagulant therapy depends not only on assessment of their intrinsic risk of thromboembolism but also on identification of those at increased risk of bleeding complications.

Striking a fine balance

Preventing Stroke - Avoiding Bleeds CHA2DS2-VASc - HAS-BLED

Oral OAC therapy (vitamine K antagonist like Warfarin) has been the cornerstone of treatment for stroke prevention in the setting of AF(1) : adjusted-dose warfarin reduce stroke by +/- 60% In AF patients Warfarin prevent more strokes than Aspirin but cause more (fatal) bleeding than Aspirin(2)

(1) Hart RG et al. Ann intern Med 2007; 146(12) : 857-867 (2) Hart RG et al. Ann. Intern Med 1999 ; 131 ; 492-501

There are significant issues with Warfarin • Narrow therapeutic range (INR target >2 and 90% of patients with nonvalvular AF(1).
So left atrial appendage occluders have been developed : • no need for further chronical anticoagulant therapy • protection for the patient from thromboembolism (1) Blackshear JL et al. Ann. Thorac Surg 1999 ; 61(2) : 755-759

Although anticoagulation is the cornerstone therapy a lot of patients have a relative or absolute contraindication to anticoagulant treatment In this group of patients LAA occlusion has great potential given than in patients with non valvular atrial fibrillation, stroke is the result of thrombus from LAA and the fact that with successfull occlusion of LAA, 90% of the patients are protected

The anatomy of the LAA is very complex • 1 or multiple lobes • Big variations in size, diameter and length • Multiple crevices and pockets (thrombus formation if stasis resulting from lack of contractility during AF

2 devices Watchman (Atritech) (protect AF trial)(1)

(1) D. Holmes et al. Lancet 2009 ; 374 : 534-42

Amplatzer Cardiac plug (AGA)

Protect AF trial (D. Holmes et al.) Lancet 2009; 374 : 534 - 42

Adult patients with nonvalvular AF were eligible for inclusion in the trial if they had at least 1 of the following : previous CVA or TIA, congestive heart failure, diabetes, hypertension or >75 years old • 707 eligible patients • Randomisation 2:1 to percutaneous LAA closure (wathman = filter)device and subsequent discontinuation of Warfarin (intervention group n=463) or to Warfarin treatment with target INR >2 and efficacy of percutaneous closure of the LAA was NON INFERIOR to that of Warfarin therapy. But there were more adverse safety events in the intervention group (periprocedural complications like airembolism, device embolisation and pericardial effusions)

1)

2)

Closure of the LAA might provide an alternative strategy to chronic Warfarin/OAC treatment for stroke prophylaxis in patients with nonvalvular AF Indicated for patients with high cardioembolic risk and contraindications to Warfarin/OAC

Case : ♀ 69 years old History of hypertension, heart failure, renal failure, alcohol abusus 2009 : AF with tachycardiomyopathy
electrical cardioversion (Chadsvasc 4/9, Hasbled 5/9)

05.2010 : CVA under Warfarin (INR 1)

11.2010 : Subdural hematoma + subarachnoidal bleeding under Warfarin (INR 3.6) (Chadsvasc 6/9, Hasbled 7/9) Indication+++ and contraindication+++ to OAC

02.2011 : Percutaneous LAA closure under general anesthesia and TOE
ASA ≥ 6 months
Clopidogrel 1 month
Endocarditis profylaxis 6 months