Catheter ablation of monomorphic ventricular tachycardia Department of Cardiology, IKEM, Prague, Czech Republic
DECLARATION OF CONFLICT OF INTEREST None
Ventricular tachycardia ablation in IKEM, Prague 2006-2010 ES/incessant VT
Mapping and ablation strategies
Ventricular tachyarrhythmias in CAD Anatomic substrate Substrate for reentrant monomorphic VTs
Mapping during VT Reentry Stp. MI EF LV 20 % Incessant VT In patients with ES hemodynamic support might be neccessary
Mapping during VT Reentry Middiastolic signal during VT
Mapping during VT Reentry Concealed entrainment 350ms 330ms
Mapping during VT Focal Case patient with nonischemic CMP and incessant VT originating from the right side of the interventricular septum
Substrate mapping A revolutionary concept Bipolar voltage map Normal Myo 4.8±3.1mV Scar < 1.5mV Dense scar <0.5mV Border zone = adjacent to dense scar 9 CAD pts and 7CMP pts with unmappable VTs Sequentional RF application to achieve linear lesions 81% W/O VT, all others but 1 improvement Marchlinsky et al, Circulation 2000;101:1288
Unmappable VTs Ablation strategies Linear lesions (Marchlinsky, Circulation 2000) Scar Mitral annulus Scar scar Transsection of channels of slow conduction within the scar Encircling of the scar Late potentials abolition Arenal, JACC 2003 LAVA elimination (local abnormal ventricular activities) Jais, HRS, 2011 Rarely focal ablation
Integrated approach Creation of voltage map during sinus rhythm Annotation of Fragmented signals Late potentials Pacemapping Location of exit for inducible VTs Delineation of channels of conduction Scar tag in case of noncapture at 10V
Arrhythmogenic substrate Effect of reperfusion Early reperfusion in CAD is associated with: Less dense and less confluent scar with thicker layer of viable myocardium Faster VTs (247±40 v 287±63ms) Lower inducibility of VTs (56% vs 79%) Wijnmaalen AP et al. Circulation 2010;121:1887-1895 Piers S et al. Circ Arrhythm Electrophysiol 2011;4:195-201
Arrhythmogenic substrate Role of imaging Transmural scar of anterior wall Inhomogeneous scar of inferior wall Subendocardial scar on lateral wall
Nonischemic cardiomyopathy Arrhythmogenic substrate Endocardial scar comprised <25% of endocardial surface in 14/19 pts, 88% of 57 mapped VTs from basal scar region Hsia HH, et al. Circulation 2003;108:704-710
Substrate mapping in nonischemic CMP Epicardial approach Case Patient with repeated ICD discharges for monomorphic focal VT from RVOT, endocardial ablation within RVOT unsuccessful
Epicardial mapping Middiastolic signals during VT
Nonischemic cardiomyopathy Septal VTs MA TA Apex Alternative approaches to VT ablation may be necessary Bipolar ablation Alcohol ablation
Surgery for VT Intraoperative mapping Surgical approach using minithoracotomy Targeting the cryoablation using intraoperative mapping with patch with 16 electrodes
Surgical therapy for electric storm Resection of aneurysm and cryodestruction of arrhythmogenic substrate Ventricular assist device (Heart Mate II, Thoratec) Heart transplant
VT ablation on the VAD Case Patient with IHD, terminal heart failure with left ventricular assist device (Heart Mate II) Recurrent runs of VT leading to hemodynamic deterioration
Outcome
Catheter ablation in the setting of electric storm is life-saving Carbucichio et al. Circulation 2008;117:462-469 95 pts with electric storm CAD, DCM, ARVC, NYHA 2.9±1.1 Prior the procedure mean 14±8 ICD discharges/day Amiodarone in 94%, BB in 97% After 1-3 procedures (in 12/95 repeated procedures) Abolition of clinical VT in 89% pts In 72% pts abolition of all inducible VTs Follow up 22 months (1 to 43 months) 92% without recurrence of electric storm 66% pts without recurrence of any VT
Catheter ablation in the setting of electric storm is life-saving
Catheter ablation for ES Prague experience Most of the events were observed within first 6 months 2004-2008, 50 pts w ES, 42 males, mean age 59±13years, LVEF 29±11%, 75%CAD VT induced/pt 2,8±1,8, 22% incessant, 27% polymorphic, epicardial access in 8% cases Clinical VT eliminated after 1-3 procedures in 84% 44% non-inducibility, 40% inducible only fast VTs, 6% failure, 11% non tested 14 pts (28%) died during FU 2 years 2 pts died due to recurrence of electrical storm 3 pts died within 1 week after the procedure due to acute heart failure 8 pts died remotely - mainly due to progression of CHF Kozeluhova M, et al. Europace. 2011 Jan;13(1):109-13.
Catheter ablation for ES Prague experience Only two variables were found to predict the risk of early death/heart Tx Low LV EF (22±3% vs 31±12%, p<0,005) Recurrent storm despite the ablation procedure (p<0,05) Kozeluhova M, et al. Europace. 2011 Jan;13(1):109-13.
Catheter ablation in Electric storm using Remote Navigation 2008-2009, 30 consecutive pts w. CAD 26 men, age 70±9, EF 30±9% and electric storm due to monomorphic VT, mean 2:3±1,2) inducible VTs RF ablation using remote MNS and a magnetic irrigated tip catheter Acute success (noninducibility of any VT) in 24 (80%) pts No acute complications were observed during the procedures Mean follow-up of 8months, 221 pts (70%) had no recurrence of VT and received no ICD therapy Arya A, et al. PACE 2010;33:1312-18
How to further improve the ablation outcome?
Prophylactic catheter ablation in ICD patients 65% reduction Trend towards lower risk of electric storm (4% vs 19% p=0.06) Reddy V, et al. N Engl J Med 2007;357:2657-65
Catheter ablation vs AA therapy Metaanalysis Mallidi J, et al. Heart Rhythm 2011;8:503-10
Argument for earlier 98pts with VT referred for VT ablation early vs late referral 2 or more VT episodes separated by more than month 67% were taking 400mg amiodarone, 58% pts in VT storm Procedural success in 89% Mean VT episodes decreased from 17 per month preceding ablation to 1 pro 6 months following ablation (p<0,01) Early referral group had superior 1- year VT free survival (p=0,01) intervention Frankel DS, et al. JCE 2011
Conclusion Catheter ablation for electric strom is effective and life-saving procedure and should be indicated early Alternative ablation strategies may be necessary Surgery and/or mechanical assist device may be used when ablation fails There is growing evidence favouring prophylactic ablation in secondary prevention ICD patients
Thank you for attention!