How to perform epicardial ablation of VT
Richard SchillingSt. Bartholomew’s Hospital
London, UK
Why epicardial ablation of VT?
Koa-Wing et al JCE 2007
Epicardial approaches
• Transarterial (ethanol)• Tranvenous (Coronary sinus)• Transpericardial
Epicardial Guide Wire Mapping
• Used with ethanol or venous ablation
• Useful for identification of target vessel
Ethanol ablation - Region identified with conventional
catheter
Relevant vessel identified at angiography
Guide wire mapping
Guide wire mapping
Balloon inserted into vessel
Saline injected into over-the-wire balloon
Dye injected to confirm infarct region and confirm no spill
Post op
• CK 300• 6 minutes on ex test no VT off drugs• EP study no VT• Discharged well no further VT
Transvenous ablation
Epicardial - transvenous
Epicardial - transvenous
Epicardial - transvenous
Transpericardial Technique - Best endocardial position
• punctures -heparinisation
• Puncture site adjusted to region of interest
• Obesity• Post-surgical patients
fail if not inferior origin
Pericardial puncture
• Slight resistance felt as diaphragm crossed
• Rubbing of needle• Tenting of
pericardium• Limit contrast• LAO view of wire
Pericardial mapping
Complications of epicardial approach8% RV perf and haemopericardium
Sosa et al JACC 2000
0% Cesario Heart Rhythm 2006
6% transient pericarditis
Schweikert et al Circ 2003
5% transient pericarditis
Personal data
Coronary vessel puncture/transient bleeding
Tedrow et al JCE 2009
Pericardial access
• May be limited in redos• Not usually a problem in post MI• Usually not worth trying in post CABG
NICE Guidelines
• No review by advisors prior to publication• Procedures should only be carried out in
units with cardiothoracic surgery
74 yr male frequent ICD shocks
• VT1 – clinical VT– Tolerated– ATP accelerated– Terminated and
non-inducible after RF at first procedure
• VT2 repeatedly induced at first procedure
• Poorly tolerated• ATP unreliable
Second ablation attempt
• VT1 endocardial mapping
VT1 endocardial RF1
VT3 induced - Epicardial site
Myocardial thickness
RF 2 epicardial VT3 to VT4 390 to 330 ms
VT4 recurrently initiated and poorly tolerated
Pacemap poor match for VT4
VT 4 non-inducible
18 year old incessant
• Endocardial
18 year old incessant VT
Barts VT protocol
Conclusions
Epicardial ablation possible from a number of approachesProbably necessary in 10% of VT (higher in DCM and idiopathic)Safe but requires experience