Relationship between successful ablation sites and the scar border zone defined by substrate mapping for ventricular tachycardia post-myocardial infarction.
BACKGROUND
It is unknown if identification of scar border zones by electroanatomical mapping correlates with successful ablation sites determined from mapping during ventricular tachycardia (VT) post-myocardial infarction (MI). We sought to assess the relationship between successful ablation sites of hemodynamically stable post-MI VTs determined by mapping during VT with the scar border zone defined in sinus rhythm.


RESULTS
Forty-six patients presenting with hemodynamically stable, mappable monomorphic VT post-MI and who had at least one such VT successfully ablated were prospectively included in the study. In each patient, VT was ablated by targeting regions during VT that exhibited early activation, +/- isolated mid-diastolic potentials, and concealed entrainment suggesting a critical isthmus site. Prior to ablation, a detailed sinus-rhythm CARTO voltage map of the left ventricle was obtained. A voltage <0.5 mV defined dense scar. Successful VT ablation sites were registered on the sinus voltage map to assess their relationship to the scar border zone. Of the 86 VTs, 68% were successfully ablated at sites in the endocardial border zone. The remaining VTs had ablation sites within the scar in (18%), in normal myocardium (4%), and on the epicardial surface (10%). There were no significant differences in VT recurrence amongst the different groups.


CONCLUSIONS
Successful ablation sites of hemodynamically stable, monomorphic VTs post-MI are often located in the scar border zone as defined by substrate voltage mapping. However, in a sizable minority, ablation sites are located within endocardial scar, epicardially, and even in normal myocardium.
Verma
Atul
A
Department of Cardiology, Section of Cardiac Pacing and Electrophysiology, Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
Marrouche
Nassir F
NF
Schweikert
Robert A
RA
Saliba
Walid
W
Wazni
Oussama
O
Cummings
Jennifer
J
Abdul-Karim
Ahmad
A
Bhargava
Mandeep
M
Burkhardt
J David
JD
Kilicaslan
Fethi
F
Martin
David O
DO
Natale
Andrea
A
D000368:Aged; D000704:Analysis of Variance; D018780:Body Surface Potential Mapping; D017115:Catheter Ablation; D002921:Cicatrix / Q000473:pathology*; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000150:complications*; D011446:Prospective Studies; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000601:surgery*; D016896:Treatment Outcome