Catheter ablation of multiple ventricular tachycardias after myocardial infarction guided by combined contact and noncontact mapping

TY - JOUR

T1 - Catheter ablation of multiple ventricular tachycardias after myocardial infarction guided by combined contact and noncontact mapping

AU - Klemm, Hanno U

AU - Ventura, Rodolfo

AU - Steven, Daniel

AU - Johnsen, Christin

AU - Rostock, Thomas

AU - Lutomsky, Boris

AU - Risius, Tim

AU - Meinertz, Thomas

AU - Willems, Stephan

PY - 2007/5/29

Y1 - 2007/5/29

N2 - BACKGROUND: Insights gained from noncontact mapping of ventricular tachycardia (VT) have not been systematically applied to contact maps. This study sought to unify both techniques for an individualized approach to the patient with multiple ischemic VTs irrespective of cycle length.METHODS AND RESULTS: For 12 consecutive patients with chronic myocardial infarction and recurrent VT, bipolar contact maps were acquired during sinus or paced rhythm. Additional noncontact maps were obtained during 48 induced VTs (cycle length 192 to 579 ms). Endocardial exit sites were superimposed on contact maps and verified by pace-mapping. Radiofrequency lesions were extended for critical borders defined by multiple neighboring exits and followed the isovoltage contour line of contact maps. Nine critical borders were identified in 8 patients and constituted the substrate for 31 VTs. The voltage at exit sites was 0.8 mV (range 0.1 to 2.3). Noncontact maps revealed 23+/-18% of isthmus conduction. Thirty-seven (77%) of all and 83% of clinically documented VTs were rendered noninducible irrespective of cycle length by application of 27 radiofrequency lesions (range 18 to 56). Spontaneous transitions between distinct VTs along critical borders were demonstrated in 4 patients. Pace-mapping reproduced the QRS morphology of 81% of VTs and was associated with successful ablation (P<0.01). Noninducibility of any sustained VT was reached for 8 (67%) patients. During 15 months (range 5 to 28) of follow-up, 8 patients remained without recurrence, and VT episodes were reduced in the other 4 patients (P<0.01). VT cycle length was not predictive for acute or long-term success.CONCLUSIONS: The combined approach of contact and noncontact mapping effectively defines critical borders as the substrate of multiple VTs without limitation for unstable VTs.

AB - BACKGROUND: Insights gained from noncontact mapping of ventricular tachycardia (VT) have not been systematically applied to contact maps. This study sought to unify both techniques for an individualized approach to the patient with multiple ischemic VTs irrespective of cycle length.METHODS AND RESULTS: For 12 consecutive patients with chronic myocardial infarction and recurrent VT, bipolar contact maps were acquired during sinus or paced rhythm. Additional noncontact maps were obtained during 48 induced VTs (cycle length 192 to 579 ms). Endocardial exit sites were superimposed on contact maps and verified by pace-mapping. Radiofrequency lesions were extended for critical borders defined by multiple neighboring exits and followed the isovoltage contour line of contact maps. Nine critical borders were identified in 8 patients and constituted the substrate for 31 VTs. The voltage at exit sites was 0.8 mV (range 0.1 to 2.3). Noncontact maps revealed 23+/-18% of isthmus conduction. Thirty-seven (77%) of all and 83% of clinically documented VTs were rendered noninducible irrespective of cycle length by application of 27 radiofrequency lesions (range 18 to 56). Spontaneous transitions between distinct VTs along critical borders were demonstrated in 4 patients. Pace-mapping reproduced the QRS morphology of 81% of VTs and was associated with successful ablation (P<0.01). Noninducibility of any sustained VT was reached for 8 (67%) patients. During 15 months (range 5 to 28) of follow-up, 8 patients remained without recurrence, and VT episodes were reduced in the other 4 patients (P<0.01). VT cycle length was not predictive for acute or long-term success.CONCLUSIONS: The combined approach of contact and noncontact mapping effectively defines critical borders as the substrate of multiple VTs without limitation for unstable VTs.

KW - Aged

KW - Body Surface Potential Mapping/methods

KW - Cardiac Pacing, Artificial

KW - Catheter Ablation

KW - Electrocardiography/methods

KW - Female

KW - Follow-Up Studies

KW - Humans

KW - Male

KW - Middle Aged

KW - Myocardial Infarction

KW - Recurrence

KW - Tachycardia, Ventricular/therapy

KW - Treatment Outcome

U2 - 10.1161/CIRCULATIONAHA.106.668673

DO - 10.1161/CIRCULATIONAHA.106.668673

M3 - SCORING: Journal article

C2 - 17502573

VL - 115

SP - 2697

EP - 2704

JO - CIRCULATION

JF - CIRCULATION

SN - 0009-7322

IS - 21

ER -