BACKGROUND: The substrate for ventricular tachycardia (VT) in nonischemic cardiomyopathy (NICM) has a predilection for the basolateral left ventricle with right bundle branch block VT morphology. OBJECTIVE: The purpose of this study was to describe a unique group of NICM patients with septal VT substrate. METHODS: Between 1999 and 2010, 31 (11.6%) of 266 patients with NICM undergoing VT ablation had septal substrate and no lateral involvement. Mean age was 59 ± 12 years, and ejection fraction was 30% ± 14%. Eight patients had heart block. RESULTS: Cardiac magnetic resonance showed septal delayed enhancement in 8 of 9 patients. Electroanatomic mapping demonstrated bipolar low voltage (<1.5 mV) extending from the basal septum in 22 of 31 patients. The remaining 9 patients had normal endocardial bipolar voltage but abnormal unipolar septal voltage (<8.3 mV) consistent with intramural abnormalities. Epicardial mapping in 14 patients showed no scar in 9 and patchy basal left ventricular summit scar in 5. VTs were mapped to the septal substrate, with 62% having right bundle branch block morphology and V(2) precordial transition pattern break in 17% suggesting periseptal exit. After substrate and targeted VT ablation, no VT was inducible in 66% and no "clinical targeted" VT in 86%. Over a mean follow-up of 20 ± 28 months, VT recurred in 10 (32%) patients. CONCLUSION: Isolated septal VT substrate is uncommon in NICM. Biventricular low-voltage zones extending from the basal septum are characteristic, but septal scarring can be entirely intramural as evidenced by unipolar/bipolar electrograms and imaging. Multiple unmappable morphologies are the rule, often requiring several procedures aggressively targeting the septal substrate to achieve moderate long-term VT control.
BACKGROUND: The substrate for ventricular tachycardia (VT) in nonischemic cardiomyopathy (NICM) has a predilection for the basolateral left ventricle with right bundle branch block VT morphology. OBJECTIVE: The purpose of this study was to describe a unique group of NICM patients with septal VT substrate. METHODS: Between 1999 and 2010, 31 (11.6%) of 266 patients with NICM undergoing VT ablation had septal substrate and no lateral involvement. Mean age was 59 ± 12 years, and ejection fraction was 30% ± 14%. Eight patients had heart block. RESULTS: Cardiac magnetic resonance showed septal delayed enhancement in 8 of 9 patients. Electroanatomic mapping demonstrated bipolar low voltage (<1.5 mV) extending from the basal septum in 22 of 31 patients. The remaining 9 patients had normal endocardial bipolar voltage but abnormal unipolar septal voltage (<8.3 mV) consistent with intramural abnormalities. Epicardial mapping in 14 patients showed no scar in 9 and patchy basal left ventricular summit scar in 5. VTs were mapped to the septal substrate, with 62% having right bundle branch block morphology and V(2) precordial transition pattern break in 17% suggesting periseptal exit. After substrate and targeted VT ablation, no VT was inducible in 66% and no "clinical targeted" VT in 86%. Over a mean follow-up of 20 ± 28 months, VT recurred in 10 (32%) patients. CONCLUSION: Isolated septal VT substrate is uncommon in NICM. Biventricular low-voltage zones extending from the basal septum are characteristic, but septal scarring can be entirely intramural as evidenced by unipolar/bipolar electrograms and imaging. Multiple unmappable morphologies are the rule, often requiring several procedures aggressively targeting the septal substrate to achieve moderate long-term VT control.
Authors: Edmond M Cronin; Frank M Bogun; Philippe Maury; Petr Peichl; Minglong Chen; Narayanan Namboodiri; Luis Aguinaga; Luiz Roberto Leite; Sana M Al-Khatib; Elad Anter; Antonio Berruezo; David J Callans; Mina K Chung; Phillip Cuculich; Andre d'Avila; Barbara J Deal; Paolo Della Bella; Thomas Deneke; Timm-Michael Dickfeld; Claudio Hadid; Haris M Haqqani; G Neal Kay; Rakesh Latchamsetty; Francis Marchlinski; John M Miller; Akihiko Nogami; Akash R Patel; Rajeev Kumar Pathak; Luis C Saenz Morales; Pasquale Santangeli; John L Sapp; Andrea Sarkozy; Kyoko Soejima; William G Stevenson; Usha B Tedrow; Wendy S Tzou; Niraj Varma; Katja Zeppenfeld Journal: J Interv Card Electrophysiol Date: 2020-10 Impact factor: 1.900
Authors: Edmond M Cronin; Frank M Bogun; Philippe Maury; Petr Peichl; Minglong Chen; Narayanan Namboodiri; Luis Aguinaga; Luiz Roberto Leite; Sana M Al-Khatib; Elad Anter; Antonio Berruezo; David J Callans; Mina K Chung; Phillip Cuculich; Andre d'Avila; Barbara J Deal; Paolo Della Bella; Thomas Deneke; Timm-Michael Dickfeld; Claudio Hadid; Haris M Haqqani; G Neal Kay; Rakesh Latchamsetty; Francis Marchlinski; John M Miller; Akihiko Nogami; Akash R Patel; Rajeev Kumar Pathak; Luis C Sáenz Morales; Pasquale Santangeli; John L Sapp; Andrea Sarkozy; Kyoko Soejima; William G Stevenson; Usha B Tedrow; Wendy S Tzou; Niraj Varma; Katja Zeppenfeld Journal: Europace Date: 2019-08-01 Impact factor: 5.214
Authors: David E Haines; Salwa Beheiry; Joseph G Akar; Janice L Baker; Doug Beinborn; John F Beshai; Neil Brysiewicz; Christine Chiu-Man; Kathryn K Collins; Matthew Dare; Kenneth Fetterly; John D Fisher; Richard Hongo; Samuel Irefin; John Lopez; John M Miller; James C Perry; David J Slotwiner; Gery F Tomassoni; Esther Weiss Journal: Heart Rhythm Date: 2014-05-07 Impact factor: 6.343
Authors: Babak Nazer; Edward P Gerstenfeld; Akiko Hata; Lawrence A Crum; Thomas J Matula Journal: J Interv Card Electrophysiol Date: 2013-12-03 Impact factor: 1.900
Authors: Takeshi Sasaki; Christopher F Miller; Rozann Hansford; Vadim Zipunnikov; Menekhem M Zviman; Joseph E Marine; David Spragg; Alan Cheng; Harikrishna Tandri; Sunil Sinha; Aravindan Kolandaivelu; Stefan L Zimmerman; David A Bluemke; Gordon F Tomaselli; Ronald D Berger; Henry R Halperin; Hugh Calkins; Saman Nazarian Journal: Circ Arrhythm Electrophysiol Date: 2013-11-14