Ventricular Tachycardia Ablation Saverio Iacopino, MD, FACC, FESC
ü Ventricular arrhythmias, both symptomatic and asymptomatic, are common, but syncope and SCD are infrequent initial manifestations of the cardiac disease
Incidence of SAD in Specific Populations and Annual SAD Numbers General adult population Multiple risk subgroups Patients with any previous coronary event Patients with ejection fraction <35% or CHF SCD-HeFT Cardiac arrest, VT/VF survivors High-risk post-mi subgroups AVID, CASH, CIDS MADIT, MUSTT, MADIT II 0 5 10 20 25 Incidence of Sudden Death (% of group) 30 0 100,000 200,000 Incidence of Sudden Deaths Per Year (number) 300,000 Adapted from: Myerburg RJ. Sudden Cardiac Death: Exploring the Limits of Our Knowledge. J Cardiovasc Electrophysiol Vol. 12, pp. 369-381, March 2001.
Pathological Progression of CV Disease Coronary artery disease Arrhythmia Underlying etiology in ~60% of CHF 1 Left ventricular injury Pathologic remodeling Low ejection fraction Death ü Hypertension ü Cardiomyopathy ü Valvular Disease Pump failure Underlying etiology in ~40% of CHF 1 ü Neurohormonal stimulation ü Endothelial dysfunction ü Myocardial toxicity ü Vasoconstriction ü Renal sodium retention Symptoms: Dyspnea Fatigue Edema Chronic heart failure 1 Adapted from Cohn JN. N Engl J Med. 1996;335:490 498. 2 He J, Ogden LG, Bazzano LA, et al. Risk Factors for Congestive Heart Failure in US Men and women: NHANES I epidemiologic follow-up study. Arch Intern Med 2001, 161: 996-1002.
Coronary Heart Disease ü An estimated 13 million people had CHD in the U.S. in 2002. 1 ü Sudden death was the first manifestation of coronary heart disease in 50% of men and 63% of women. 1 ü CHD accounts for at least 80% of sudden cardiac deaths in Western cultures. 3 Etiology of Sudden Arrhythmic Death 2,3 5% Other* 15% Cardiomyopathy 1 American Heart Association. Heart Disease and Stroke Statistics 2003 Update. 2 Adapted from Heikki et al. N Engl J Med, Vol. 345, No. 20, 2001. 3 Myerberg RJ. Heart Disease, A Textbook of Cardiovascular Medicine. 6 th ed. P. 895. 80% Coronary Heart Disease * ion-channel abnormalities, valvular or congenital heart disease, other causes
LVEF and SAD Incidence % SCA Victims 8 7 6 5 4 3 2 1 0 7.5% 5.1% 2.8% 1.4% 0-30% 31-40% 41-50% >50% LVEF Vreede-Swagemakers JJ. J Am Coll Cardiol. 1997;30:1500-1505.
Idiopathic DCM and Hystopathology Grossly visible scar in 14% of patients NORMAL HEART DCM Histology discloses fibrosis in 57% of patients interstizial fibrosis replacement fibrosis Unverferth DV. AMJ. 1986;57:816-820 Roberts WC. AMJ. 1987;60:1340-1355 Nakayama Y. JACC. 1987;10:186-192
Reentry VT
LV Bipolar Voltage Mapping During SR in Patient with NIDCM and VA Correlation with Histology minimal moderate extensive Pogwizd SM. Circulation. 1998;98:2404-2414
Estimation of the Abnormal LV Endocardium in a patient with Non-ischemic Cardiomyopathy Marchlinski FE. Circulation. 2003;108:704-710
Localization and Characterization of the VT circuit Marchlinski FE. Circulation. 2003;108:704-710
Non Invasive Detection of Myocardial Fibrosis in DCM Correlation of MR myocardial delayed enhancement with histology findings in DCM Different distribution patterns of Gadolinium within the myocardium ü MRI cannot differentiate inflammation from fibrosis Zimmermann O. EJHF. 2006;8:162-160 Prevalence of delayed enhancement was 69% in 42 patients with DCM as compared to 0% in 42 control subjects
Relation Between Scar Location on Delayed Enhancement Images and Morphology of VT ü LBB like configuration in lead V1 of the VT ECG suggests an exit site in the right ventricle or interventricular septum and is compatible with the scar location Nazarian S. Circulation. 2005;112:2821-2825
MRI Parameters and Comparison After Stratification by Inducibility at EPS ü noninvasive assessment of scar distribution by MRI may predict EPS results in NIDCM ü scar distribution may identify a subset of patients with mild to moderate LV dysfunction and high risk of arrhythmia not currently identified for ICD implantation Nazarian S. Circulation. 2005;112:2821-2825
Bundle Branch Reentry as the Mechanism of VT ü Accounting for 5-6% of VT cases in CAD ü And up to 40% in non ischemic DCM ü Diagnoses associated with BBR-VT (CAD excluded) ü Non ischemic DCM (50-70% of all BBR-VTs) ü Valvular heart disease ü Muscular dystrophies, hypertrophic CM, Ebstein s anomaly ü No structural heart disease but His-Purkinje conduction delays ü Heart is dilated in the vast majority of cases ü Enlarged QRS, prolonged H to V interval
Bundle Branch Reentry VT ü Reentry circuit is confined to the left and right bundle branches ü Usually LBBB, during sinus rhythm ü Presents with: ü Syncope ü Palpitations ü Sudden cardiac death ü Treatment: RF ablation of right bundle
Bundle Branch Reentry VT: Mechanism Oreto G. I Disordini del Ritmo Cardiaco - CSE 1997
Case History ü Women, 58 years old with single chamber PM ü Syncope and SVT ü Emery-Dreyfuss Syndrome ü Dilated Cardiomyopathy ü EF=40% ü NYHA class II
H H H H H H-H= V 310 V 350 V 330 V 310 V V-V= 310 350 330 310
Ablation Site: Right Bundle RVOT RVOT ABL ABL RV RV RAO LAO
Case History ü Men, 59 years old ü palpitations, dispnoea ü Syncope, ventricular ectopies and SVT ü NIDCM (EF=40%), dilated RVOT ü EKG Holter: ventricular monomorfic ectopies (28.650) and NSVT
Pacemapping Clinical Ectopies
Inducible VT
Pacemapping from ablation site Clinical VT
ü ICD have become the main therapeutic tool for patients with life-threatening VE arrhythmias ü Some patients receive multiple appropriate shocks during a short period due to arrhythmic storm ü The arrhythmic episodes was successfully controlled in the majority of patients with antiarrhythmic drug therapy
Kaplan-Meier event-free Survival Estimates in Patient Population During Follow up P Della bella et al. Circulation 2008
Kaplan-Meier event-free Survival Estimates According to Acute CA Results During Follow up P Della bella et al. Circulation 2008
ü Despite the evidence-based data and practical recommendations for indications of ICD therapy and ablation, these therapy has not been uniformly implemented worldwide
NYHA Ischemia EPS EF VPBs/nsVT HRV SAD TWA SAECG BRS QT d BNP QRS d
Markers of Arrhythmic Risk ü Simple factors ü Prognostic indicator ü Determining decision-making?