Background
The ventricular tachycardia (VT) circuit is often assumed to be located in the endocardium
or epicardium. The plateauing success rate of VT ablation warrants reevaluation of
this mapping paradigm.
Objective
The purpose of this study was to resolve the intramural components of VT circuits
by mapping in human hearts.
Methods
Panoramic simultaneous endocardial–epicardial mapping (SEEM) during intraoperative
mapping (IOM) was performed in human subjects. In explanted hearts (EH), SEEM and
intramural multielectrode plunge needle mapping (NM) of the left ventricle were performed.
Overall, 37 VTs (26 ischemic cardiomyopathy [ICM], 11 nonischemic cardiomyopathy [NICM])
were studied in 32 patients. Intraoperative SEEM was performed in 16 patients (16
ICM). Additionally, 16 explanted myopathic human hearts (9 NICM, 7 ICM) were studied
in a Langendorff setup. Predominant intramural location of the VT was imputed by the
absence of significant endocardial–epicardial activation during IOM (using SEEM and
no NM) or by the presence of intramural activation spanning the entire cycle length
(including mid-diastole) in EH (SEEM and NM).
Results
By IOM (SEEM), predominant endocardial activation (entire tachycardia cycle length
including mid-diastolic activation) was present in 10 of 18 VTs (55%). In 8 of 18
VTs (44%), the VT circuit was presumed to be intramural due to incomplete diastolic
activation in endocardium and epicardium. In EH (SEEM and NM), VT location was predominantly
intramural, endocardial, and epicardial in 8 of 19 (42%), 5 of 19 (26%), and 1 of
19 VTs (5%), respectively.
Conclusion
In a significant proportion of both ischemic and nonischemic ventricular tachycardias,
the predominant activation was located in the intramural space.
Keywords
To read this article in full you will need to make a payment
Purchase one-time access:
Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online accessOne-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:
Subscribe to Heart RhythmAlready a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
References
- Deep myocardial ablation lesions can be created with a retractable needle-tipped catheter.Pacing Clin Electrophysiol. 2004; 27: 594-599
- Outcomes in catheter ablation of ventricular tachycardia in dilated nonischemic cardiomyopathy compared with ischemic cardiomyopathy: results from the Prospective Heart Centre of Leipzig VT (HELP-VT) Study.Circulation. 2014; 129: 728-736
- Atrial tachycardia after circumferential pulmonary vein ablation of atrial fibrillation: mechanistic insights, results of catheter ablation, and risk factors for recurrence.J Am Coll Cardiol. 2007; 50: 1781-1787
- Orientation-independent catheter-based characterization of myocardial activation.IEEE Trans Biomed Eng. 2017; 64: 1067-1077
- On-line epicardial mapping of intraoperative ventricular arrhythmias: initial clinical experience.J Am Coll Cardiol. 1984; 4: 703-714
- Endocardial mapping of ventricular tachycardia in the intact human ventricle: evidence for reentrant mechanisms.J Am Coll Cardiol. 1988; 11: 783-791
- Late results of operation for ventricular tachycardia.Ann Thorac Surg. 1992; 54: 832-839
- Ablation of stable VTs versus substrate ablation in ischemic cardiomyopathy: the VISTA randomized multicenter trial.J Am Coll Cardiol. 2015; 66: 2872-2882
- Endo-epicardial homogenization of the scar versus limited substrate ablation for the treatment of electrical storms in patients with ischemic cardiomyopathy.J Am Coll Cardiol. 2012; 60: 132-141
- Early reperfusion during acute myocardial infarction affects ventricular tachycardia characteristics and the chronic electroanatomic and histological substrate.Circulation. 2010; 121: 1887-1895
- Reentrant and focal mechanisms underlying ventricular tachycardia in the human heart.Circulation. 1992; 86: 1872-1887
- Epicardial and endocardial mapping of ventricular tachycardia in patients with myocardial infarction. Is the origin of the tachycardia always subendocardially localized?.Circulation. 1991; 84: 1058-1071
- Characteristics of electrograms recorded at reentry circuit sites and bystanders during ventricular tachycardia after myocardial infarction.J Am Coll Cardiol. 1999; 34: 381-388
- Three-dimensional architecture of scar and conducting channels based on high resolution ce-CMR: insights for ventricular tachycardia ablation.Circ Arrhythm Electrophysiol. 2013; 6: 528-537
- Ablation for ventricular tachycardia: is more always better? How much more is too much?.J Am Coll Cardiol. 2012; 60: 142-143
- Delayed-enhanced magnetic resonance imaging in nonischemic cardiomyopathy: utility for identifying the ventricular arrhythmia substrate.J Am Coll Cardiol. 2009; 53: 1138-1145
- Myocardial structural associations with local electrograms: a study of post-infarct ventricular tachycardia pathophysiology and magnetic resonance based non-invasive mapping.Circ Arrhythm Electrophysiol. 2012; 5: 1081
- Combined endocardial-epicardial versus endocardial catheter ablation alone for ventricular tachycardia in structural heart disease: a systematic review and meta-analysis.JACC Clin Electrophysiol. 2019; 5: 13-24
- Scar homogenization versus limited-substrate ablation in patients with nonischemic cardiomyopathy and ventricular tachycardia.J Am Coll Cardiol. 2016; 68: 1990-1998
- Epicardial ablation of ventricular tachycardia: an institutional experience of safety and efficacy.Heart Rhythm. 2013; 10: 490-498
- Large radiofrequency ablation lesions can be created with a retractable infusion-needle catheter.J Cardiovasc Electrophysiol. 2006; 17: 657-661
- Endocardial and epicardial radiofrequency ablation of ventricular tachycardia associated with dilated cardiomyopathy: the importance of low-voltage scars.J Am Coll Cardiol. 2004; 43: 1834-1842
- Initial human feasibility of infusion needle catheter ablation for refractory ventricular tachycardia.Circulation. 2013; 128: 2289-2295
- Prognostic significance of ventricular ectopic beats with respect to sudden death in the late postinfarction period.Circulation. 1973; 47: 959-966
Article info
Publication history
Published online: October 15, 2019
Footnotes
This work was funded by CIHR MOP: 142272. Dr Bhaskaran is a Burnett fellow. Dr Nanthakumar is an investigator at TGHRI and HSF. All other authors have reported that they have no conflicts relevant to the contents of this paper to disclose.
Identification
Copyright
© 2019 Heart Rhythm Society. All rights reserved.
