Role of cardiac imaging for catheterbased left atrial appendage closure Ana G. Almeida, MD, PhD Cardiology University Hospital Santa Maria, Lisbon Ana G. Almeida, MD, PhD, FESC University Hospital Santa Maria Faculty of Medicine of Lisbon University anagalmeida@gmail.com
Declaration of interests No disclosures to report
Atrial fibrillation and risk AF is the most common cardiac arrhythmia Affects about 6 million individuals in the US Predicted increase to 15.9 million by 2050 Patients with AF have a 5-fold higher risk of stroke 5%/year incidence >40 year-old men and women
LAA and AF The left atrial appendage (LAA) is the major location of thrombi in patients with AF The 4 largest TEE studies, comprising 1181 patients, demonstrated that 98% of left atrial thrombi were found in the LAA
Non-rheumatic AF and thrombus location Blackshear JL, Odell JA. Ann Thorac Surg 1996
Rational for LAA occlusion Long-term oral anticoagulation therapy with warfarin or novel anticoagulants is recommended irrespective of the rhythm management strategy but is limited by Risk of major bleedings (1.4 to 3.0%/year) Contra-indications Drug interactions Warfarin: narrow therapeutic range and need for monitoring Incomplete compliance
LAA percutaneous closure LAA closure has been proposed as an alternative method for preventing thromboembolism in patients with AF LAA percutaneous closure devices: PLATTO Watchman ACP (Amplatzer Cardiac Plug)
PLAATO 5 years estimated stroke risk based in CHADS 2 Block PC et al. JACC Interv 2009
PROTECT AT trial The PROTECT AF trial was conducted with the hypothesis of a noninferiority of the LAA closure with Watchman, in comparison with warfarin (Am Heart J, 2006) Patients non-valvular AF & previous stroke or TIA, congestive HF, diabetes, hypertension, or 75 year-older (CHADS 2 1) Follow-up: 18±10 months
PROTECT AF endpoints Primary efficacy All stroke (ischemic or haemorragic) Systemic embolism CV and unexplained death Primary safety Device embolisation Pericardial effusion requiring intervention Cranial and GI bleeds Any bleeding that requires >=2U PRBC
NON- INFERIORITY Probability>99.9%
Holmes DR et al. Lancet 2009; 374: 534
Which is the role of imaging in the LAA closure procedure?
Role of imaging Selecting patients Planning the procedure Intra-procedural monitoring Follow-up after procedure Detection of complications Imaging is essential! Transesophageal Echo (TEE) Cardiac CT (CT) Cardiovascular magnetic resonance (CMR)
I Selecting patients Assessing exclusion criteria for the procedure: Atrial and/or LAA thrombus TEE/CT/CMR Significant valvular disease Clinical/TTE Previous incomplete surgical LAA ligation TEE/CT/CMR Before / During procedure
II Planning the procedure - LAA morphology Cactus type Chicken wing type Windsock type Cauliflower type Di Biase L et al. JACC 2012
LAA morphology Non-circular proximal and distal portions and different angulations Proximal Distal Lacomis J et al. Europace 2007
LAA TEE 2D measurements Neck and length 0º; 45º; 90º & 135º
LAA - CT measurements LAA neck and length dimensions Oblique orientations obtained from 3D along the LAA ostium 2D is superior do 3D Measurements from oriented planes are more reproducible than from orthogonal ones Ostium perimeter is superior to diameters for sizing the device Wang Y et al, JCE, 2010
CMR measurements similar to CT
III TEE procedure guidance Male, 83 y-old, AF, CHADS2=3, lower GI bleeding (diverticular disease)
Measurements - before or intra-procedure session TEE LAA 0º; 45º; 90º & 135º 29x18mm 24x17mm 31x17mm 31x23mm A. Almeida, S. Martins, E. Infante de Oliveira, L. Carpinteiro, João de Sousa, P. Canas da Silva, A. Nunes Diogo
Device size selection
Transeptal puncture - TEE guidance for guidewire A. Almeida, S. Martins, E. Infante de Oliveira, L. Carpinteiro, J. Sousa, P. Canas da Silva, A. Nunes Diogo
LAA Angiogram A. Almeida, S. Martins, E. Infante de Oliveira, L. Carpinteiro, J. Sousa, P. Canas da Silva, A. Nunes Diogo
Device Positioning Watchman 27 mm A. Almeida, S. Martins, E. Infante de Oliveira, L. Carpinteiro, J. Sousa, P. Canas da Silva, A. Nunes Diogo
Device Deployment Watchman 27 mm A. Almeida, S. Martins, E. Infante de Oliveira, L. Carpinteiro, J. Sousa, P. Canas da Silva, A. Nunes Diogo
Closure evaluation - Watchman 27 mm A. Almeida, S. Martins, E. Infante de Oliveira, L. Carpinteiro, J. Sousa, P. Canas da Silva, A. Nunes Diogo
Partial Recapture Watchman 27 mm A. Almeida, S. Martins, E. Infante de Oliveira, L. Carpinteiro, J. Sousa, P. Canas da Silva, A. Nunes Diogo
Reposition & Deployment Watchman 27 mm A. Almeida, S. Martins, E. Infante de Oliveira, L. Carpinteiro, J. Sousa, P. Canas da Silva, A. Nunes Diogo
Device size re-selection
Watchman 33 mm A. Almeida, S. Martins, E. Infante de Oliveira, L. Carpinteiro, J. Sousa, P. Canas da Silva, A. Nunes Diogo
Device Release Watchman 33 mm No para-device flow RAO-CAUDAL A. Almeida, S. Martins, E. Infante de Oliveira, L. Carpinteiro, J. Sousa, P. Canas da Silva, A. Nunes Diogo
3D TEE En face view A. Almeida, S. Martins, E. Infante de Oliveira, L. Carpinteiro, J. Sousa, P. Canas da Silva, A. Nunes Diogo
IV Procedural complications Procedure efficacy criteria complete closure of LAA or minimal residual peri-device flow, jet <5 mm in width PROTECT AF procedural complications (7 days) 12.3% Serious pericardial effusion 4.8% Device embolisation/sepsis 0.3% (4) Procedural-related ischemic stroke 1.1% Peri-procedural imaging allows confirming closure efficacy and detecting pericardial effusion
CAP-trial - Device-safety events during follow-up Learning curve decreased complications Modifications of the device lower pericardial effusion events Modification in the delivery system less strokes events Pericardial effusion: 5.2% 2.2%; stroke: 1.1% 0%; embolization: 0.3% 0% Reddy V et al. Circulation 2011
Importance of the Learning Curve PROTECT-AF Tertiles by Enrollment Date and CAP registry Are there other factors which contributed to these results?? We believe so, because imaging guidance is now mandatory
Long-term complications Proposed follow-up strategy TEE at 45 days, 6 months and 12 months Warfarin for 45 days clopidogrel + aspirin for 6 months long-term aspirin Complications - importance of imaging Device thrombus (PROTECT AF 2009, CAP Registry 2011) 4.2%, different time frames stroke rate of 0.3% per 100 patient-years Peri-device leak incomplete sealing 32% of implanted device, at 12 months
445 pts; peri-device flow of 1-5 mm width at 45dy (40.9%), 6 (33.8%) and 12-month (32.1%) TEE no association with stroke, systemic embolism and CV death PROTECT AF Substudy. Viles-Gonzales J et al. JACC 2012;59:923
3 mm width leak Peri-device leak at 45 th day
No events at 24 months f-up and no flow on TEE and CT
Conclusions Imaging improves safety and success Pre-procedural evaluation LAA anatomy rule out thrombi and severe autocontrast Procedural guidance Transeptal puncture guidance Device release process Position Compression Stability Seal Post-procedural evaluation
Acknowledgments Imaging Lab A. Almeida S. Martins Catheterization Lab E. Infante de Oliveira P. Canas da Silva Technicians Arrhythmology Lab J. Sousa L. Carpinteiro N. C. Dias Dept Head and Co-Head A. Nunes Diogo F. Pinto Cardiology Department University Hospital Santa Maria/C.H.L.N Faculty of Medicine of Lisbon University