A case of pulsed field ablation for refractory midmyocardial origin ventricular tachycardia in the left ventricle

Options for ventricular tachycardia ablation after double valve replacement

An optimized multisource acquisition and registration workflow for imaging guided ventricular tachycardia ablation

A case of incessant VT from an intramural septal focus: Ethanol or bipolar ablation?

Focal pulsed field ablation for ventricular tachycardia in ischemic heart disease: a case series

Radiofrequency ablation is an effective treatment strategy for ischemic and nonischemic cardiomyopathy-related ventricular tachycardia (VT). The role of substrate-guided ablation, performed using electrogram characteristics (low amplitude, fractionated or isolated potentials) as scar surrogates, is expanding because of frequent hemodynamic instability during entrainment mapping of scar-related VT. Late gadolinium-enhancement on cardiac magnetic resonance imaging (LGE-MRI) can accurately characterize the transmural extent, location, and configuration of ventricular scar.1 Integration of LGE-MRI into electroanatomical mapping during VT ablation was shown, in preliminary studies, to be feasible and to provide accurate localization of VT substrate and reentry circuits.2–4 However, studies to date examining the impact of MRI scar integration on procedural outcomes have lacked control groups, precluding any comparisons with standard practice. We performed a study to (1) demonstrate the feasibility in clinical practice of integrating MRI-derived scar for guidance of VT ablation; (2) report on the periprocedural performance of LGE-MRI in identifying the arrhythmogenic substrate; and (3) examine the impact of MRI-guided ablation on procedural length and acute and long-term outcomes. In this prospective multicenter study, we enrolled 24 consecutive patients with ischemic (n=9) and nonischemic cardiomyopathy (n=15), referred for catheter ablation of scar-related monomorphic VT. Patients were assigned, at the discretion of the treating physician (not randomized), to undergo either MRI-derived scar–guided ablation or traditional ablation. Clinical characteristics of patients in both groups were statistically comparable with a higher tendency to use scar integration for patients with prior …

Although multi-detector computed tomography (MDCT) and cardiac magnetic resonance (CMR) can assess the structural substrate of ventricular tachycardia (VT) in ischemic cardiomyopathy (ICM), non-ICM (NICM), and arrhythmogenic right ventricular cardiomyopathy (ARVC), the usefulness of systematic image integration during VT ablation remains undetermined. A total of 116 consecutive patients (67 ICM; 30 NICM; 19 ARVC) underwent VT ablation with image integration (MDCT 91%; CMR 30%; both 22%). Substrate was defined as wall thinning on MDCT and late gadolinium-enhancement on CMR in ICM/NICM, and as myocardial hypo-attenuation on MDCT in ARVC. This substrate was compared to mapping and ablation results with the endpoint of complete elimination of local abnormal ventricular activity (LAVA), and the impact of image integration on procedural management was analyzed. Imaging-derived substrate identified 89% of critical VT isthmuses and 85% of LAVA, and was more efficient in identifying LAVA in ICM and ARVC than in NICM (90% and 90% vs. 72%, P < 0.0001), and when defined from CMR than MDCT (ICM: 92% vs. 88%, P = 0.026, NICM: 88% vs. 72%, P < 0.001). Image integration motivated additional mapping and epicardial access in 57% and 33% of patients. Coronary and phrenic nerve integration modified epicardial ablation strategy in 43% of patients. The impact of image integration on procedural management was higher in ARVC/NICM than in ICM (P < 0.01), and higher in case of epicardial approach (P < 0.0001). Image integration is feasible in large series of patients, provides information on VT substrate, and impacts procedural management, particularly in ARVC/NICM, and in case of epicardial approach.

Endobronchial ultrasound–guided transtracheal cardiac plexus neuromodulation for refractory ventricular tachycardia

Structure and function of the ventricular tachycardia isthmus.

Due to its unique features, pulsed field ablation (PFA) could potentially overcome some limitations of current radiofrequency (RF) ventricular tachycardia (VT) ablation. However, data on the use of PFA in this setting are currently scarce. Two patients with ischemic cardiomyopathy and previously failed RF VT ablations were treated with PFA. A total of 18 bipolar applications (case1) and seven bipolar applications (case2) were delivered to the infero-lateral and infero-septal areas (case1) and to the apical lateral left ventricular (LV) wall (case2), placing the catheter adjacent to the LVwall in the flower configuration. A rapid cessation of VT and restoration of sinus rhythm were observed during PFA delivery in both cases. Further applications were delivered to achieve complete elimination of late potentials. In case 1, during the in-hospital stay, ECG monitoring did not show VT recurrences. Six-month follow-up was uneventful, with no VT recurrences at ICD interrogation. In case 2, due to postdischarge VT recurrences, a second RF procedure was scheduled 1 month later. The voltage map performed in sinus rhythm showed a low-voltage zone located at the anterolateral wall, near the previous ablation site. Numerous late potentials were recorded. At the 6-month follow-up, no further VT recurrences were documented after RF redo ablation. While the speed of application and potential transmural effect can facilitate the ablation of large diseased endocardial areas, early loss of contact due to difficult pentaspline catheter manipulation in the LV could lead to insufficient contact force and, consequently, inadequate energy penetration.

BackgroundIn patients with severe left ventricular dysfunction, recurrent ventricular tachycardia (VT) non-responsive to antiarrhythmic therapies may cause further deterioration of cardiac function and haemodynamic instability. The use of extracorporeal membrane oxygenation (ECMO) in the setting of haemodynamically unstable VT may allow rhythm stabilization and can be effective in providing haemodynamic stability during VT ablation procedures.Case summaryWe describe the clinical course of a patient with ischaemic cardiomyopathy and recurrent VTs in the early post-myocardial infarction (MI) period. Nineteen days after MI, the patient started to experience recurrent attacks of VT, which became more frequent and non-responsive to medical treatment including amiodarone and lidocaine. The patient developed cardiogenic shock and a decision was made to institute ECMO. The patient was supported with ECMO for 32 days because of heart failure, refractory VT, and recurrent infections. An electrophysiological study was performed 4 days after ECMO initiation, which revealed a large scar area in the left ventricle. Radiofrequency energy was applied 69 times, rendering the VT non-inducible. Subsequently, VT attacks disappeared and the patient was weaned from ECMO after 32 days. The patient received a left ventricular assist device 5 days post-ECMO weaning and was then transplanted.DiscussionThere is still no evidence or guidelines regarding patients with refractory VT; however, ECMO support has been successfully used during VT ablation procedures. In this case report, VT ablation had a crucial role in treating the culprit arrhythmia while the implementation of ECMO allowed a complex ablation procedure to be completed safely.

Successful ventricular tachycardia ablation in a patient with limited vascular and left ventricular endocardial access due to multiple mechanical cardiac support devices

ORAL PROCAINAMIDE IN PATIENTS WITH STRUCTURAL HEART DISEASE AND REFRACTORY VENTRICULAR TACHYCARDIA

Ablation of ventricular tachycardia (VT) is limited by the inability to create penetrating lesions to reach intramyocardial origins. Intramural needle ablation using in-catheter, heated saline-enhanced radio frequency (SERF) energy uses convective heating to increase heat transfer and produce deeper, controllable lesions at intramural targets. This first-in-human trial was designed to evaluate the safety and efficacy of SERF needle ablation in patients with refractory VT. Thirty-two subjects from 6 centers underwent needle electrode ablation. Each had recurrent drug-refractory monomorphic VT after implantable cardioverter defibrillator implantation and prior standard ablation. During the SERF study procedure, one or more VTs were induced and mapped. The SERF needle catheter was used to create intramural lesions at targeted VT site(s). Acute procedural success was defined as noninducibility of the clinical VT after the procedure. Patients underwent follow-up at 30 days, and 3 and 6 months, with implantable cardioverter defibrillator interrogation at follow-up to determine VT recurrence. These refractory VT patients (91% male, 66±10 years, ejection fraction 35±11%; 56% ischemic, and 44% nonischemic) had a median of 45 device therapies (shock/antitachycardia pacing) for VT in the 3 to 6 months pre-SERF ablation. The study catheter was used to deliver an average of 10±5 lesions per case, with an average of 430±295 seconds of radiofrequency time, 122±65 minute of catheter use time, and a procedural duration of 4.3±1.3 hours. Acute procedural success was 97% for eliminating the clinical VT. At average follow-up of 5 months (n=32), device therapies were reduced by 89%. Complications included 2 periprocedural deaths: an embolic mesenteric infarct and cardiogenic shock, 2 mild strokes, and a pericardial effusion treated with pericardiocentesis (n=1). Intramural heated saline needle ablation showed complete acute and satisfactory mid-term control of difficult VTs failing 1 to 5 prior ablations and drug therapy. Further study is warranted to define safety and longer-term efficacy. URL: https://www. gov; Unique Identifier: NCT03628534 and NCT02994446.

Combined endocardial and epicardial ablation of drug-refractory ventricular tachycardia by direct ventricular puncture

Ventricular arrhythmia inducibility is one of the ideal endpoints of ventricular tachycardia (VT) ablation. However, it may be challenging to implement programmed electrical stimulation (PES) at the end of the procedure under several circumstances. The long-term outcome of patients who did not undergo PES after VT ablation remains largely unknown. To investigate the details and long-term outcome of VT ablation in patients who did not undergo PES at the end of the ablation procedure. Among 183 VT ablation procedures in patients with structural heart disease who underwent VT ablation using an irrigated catheter, we enrolled those who did not undergo PES after VT ablation. VT ablation strategy involved targeting clinical VT plus pacemap-guided substrate ablation if inducible. When VT was not inducible, substrate-based ablation was performed. The primary endpoint was VT recurrence. In 58 procedures, post-ablation VT inducibility was not assessed. The causes were non-inducibility of sustained VT before ablation (27/58, 46.6%), long procedure time (27.6%, mean 392min), complications (10.3%), intolerant hemodynamic state (10.3%), and inaccessible or unsafe target (6.9%). With regard to the primary endpoint, 23 recurrences (39.7%) were observed during a mean follow-up period of 2.5years. Patients with non-inducibility before ablation showed less VT recurrences (4/27, 14.8%) during follow-up than patients with other causes of untested PES after ablation (19/31, 61.2%) (Log-rank < 0.001). VT recurrence was not observed in approximately 60% of the patients who did not undergo PES at the end of the ablation procedure. PES after VT ablation may be not needed among patients with pre-ablation non-inducibility.