Predictors of freedom from atrial arrhythmia recurrence after cryoballoon ablation for persistent atrial fibrillation: A multicenter study.

AIMS: We sought to assess (1) clinical outcomes of second-generation cryoballoon (CB) ablation for persistent atrial fibrillation (AF), and (2) the association of baseline and procedural covariates with atrial arrhythmia recurrence (AAR) after ablation. METHODS: A total of 135 patients (63 ± 11 years, 96 men [71%]) with persistent AF underwent CB ablation at three experienced electrophysiology centers. Freedom from AAR was estimated with the Kaplan-Meier method. A Cox proportional-hazards model was used to estimate the effects of baseline and procedural covariates on the likelihood of AAR. RESULTS: Freedom from AAR at 6, 12, and 18 months was estimated at 91% (95% confidence interval [CI] 86%-96%), 75% (95% CI, 67%-83%), and 53% (95% CI, 43%-65%), respectively. The presence of an implantable cardiac device (Hazard ratio [HR] 3.09; 95% CI, 1.37-7.00; P = .007), a left atrial (LA) diameter > 50 mm (HR 1.69; 95% CI, 1.02-2.79; P = .043), and absence of antiarrhythmic drug (AAD) therapy before the ablation procedure (HR 3.12; 95% CI, 1.72-5.64; P < .001) were associated with AAR. A trend toward an increased risk of AAR was revealed for women (HR 1.73; 95% CI, 0.96-3.11; P = .069). CONCLUSIONS: CB ablation for persistent AF resulted in freedom from AAR about that reported for RF ablation. The presence of an implantable cardiac device, LA size, and absence of AAD therapy at baseline were associated with the risk of AAR.

Long-term follow up of 3 T MRI-detected brain lesions after percutaneous catheter-based left atrial appendage closure.

BACKGROUND: Left atrial appendage closure (LAAC) for stroke prevention is an increasingly performed intervention. AIMS: This prospective study aims to evaluate the incidence of long-term magnetic resonance imaging (MRI)-detected brain lesions as well as potential changes of neurocognitive function after percutaneous LAAC. METHODS: Brain MRI at 3 T was performed within 24 hr before and after LAAC. A follow-up MRI was carried out after three months. Neuro-cognitive examination using the National Institutes of Health Stroke Scale (NIHSS) score and the Montreal Cognitive Assessment (MoCA) Test was performed. RESULTS: Successful device implantation was achieved in all 25 patients (age 74.6 ± 10.2 years, male = 17) using the Amulet (n = 20), Occlutech (n = 3), or a Lambre (n = 2) device. In 12/25 (48%) patients, acute brain lesions (ABL) were detected after LAAC. A three-month follow-up MRI was performed in seven patients, and no new ABLs were seen. In 5/7 (71%) patients, there were no residual changes from the ABLs detectable. However, the FLAIR sequence was still positive in two patients. After LAAC, there were no significant differences in the MoCA-test (mean 24.3 ± 4.5 vs. 23.5 ± 4.5; P = 0.1) and the NIHSS-score (mean 0.9 ± 1.6 vs. 1.2 ± 1.8; P = 0.1). This was the same at the three-month follow-up (MoCA-test 23.5 ± 4.5 vs. 23.8 ± 2.7; P = 0.3; NIHSS-score 1.2 ± 1.8 vs. 1.0 ± 0.8; P = 0.4). CONCLUSION: While new MRI-detected brain lesions are commonly observed after percutaneous LAAC, ABLs were no longer detectable in 71% of the patients at the three-month follow-up. There were no significant changes in neurocognitive function after LAAC and at the three-month follow-up.

First-in-human experience of left atrial appendage occlusion with the steerable FuStar sheath.

BACKGROUND: Due the wide variability of left atrial appendage morphology left atrial appendage occlusion (LAAO) remains a challenging procedure. The steerable FuStar delivery sheath was designed to allow both, transseptal access and delivery of percutaneous devices. We here report the first-in-human experience of LAAO with the FuStar sheath. METHODS: Twenty patients (76.6 ± 8.4 years; 12 (60%) males; CHA2 DS2 -VASc score: 5.0 ± 2) with non-valvular fibrillation and contraindications to oral anticoagulation underwent LAAO with the LAmbre device using the FuStar steerable sheath (Lifetech Scientific Corp., Shenzhen, China) at two german centers. RESULTS: Successful device implantation was achieved in all patients (100%). No periprocedural complications were observed. Procedure time, fluoroscopy time, contrast media, and radiation dose were 23.4 min ± 9.2, 11.9 min ± 4.1, 96.2 mL ± 45.7, and 2718.4 cG*cm2 ± 3835.3, respectively. CONCLUSION: This study demonstrates the feasibility and safety of the steerable FuStar sheath for LAAO.

Cryoballoon ablation in the elderly: one year outcome and safety of the second-generation 28mm cryoballoon in patients over 75 years old.

Aims: The efficacy of the second-generation cryoballoon (CB) ablation in patients with atrial fibrillation (AF) has been demonstrated previously. Data on the efficacy of CB ablation in elderly patients is missing. The aim of this study was to evaluate the long-term success rate of pulmonary vein isolation (PVI) in patients ≥75 years vs. <75 years using the second-generation 28mm CB. Methods and results: Eighty patients [n = 40 ≥75 years (Group 1); n = 40 <75 years (Group 2)] with paroxysmal [n = 37 (46%) or persistent (n = 43 (54%)] AF were included. Median follow-up was 12 [6;18] months (Group 1 vs. 13 [6;27]) months (Group 2; P = 0.8). PVI was performed in all patients using cryoablation. Follow-up was obtained using 24h-Holter monitoring or via an implanted loop recorder or pacemaker. CHA2DS2VASc-Score (Group 1: 4 [4;5] vs. Group 2: 2 [1;3], P < 0.001) and HASBLED-Score (Group 1: 2 [2;3] and Group 2: 2 [1;3], (P = 0.009)) differed significantly between the two groups. Mean fluoroscopy time was 22.9 [16.3;31.9] in Group 1 and 24.5 [19.1;30.6] in Group 2 (P = 0.75), and mean procedure time was 125 min [105;151] in Group 1 and 130.5 min [117.5;147.3] in Group 2 (P = 0.66). Arrhythmia recurrence was similar in Group 1 and Group 2 (12/40 (30%) vs. 10/40 (25%) (P = 0.62). One transient ischaemic attack occurred in Group 2. No further major complications were documented in this patients cohort. Conclusion: CB ablation in patients ≥75 years has favourable success rates and similar complication rates compared with patients <75 years.

Successful re-ablation of a permanent junctional reciprocating tachycardia with cryoenergy : Case report of a 19-year-old patient.

We report the case of a 19-year-old male patient who presented with a permanent junctional reciprocating tachycardia (PJRT). After a primarily successful radiofrequency ablation of a para-Hisian, midseptal, accessory pathway, recurrence of tachycardia was documented. Thereafter, successful ablation using cryoenergy was performed. Since this second ablation the patient has been free of tachycardia. Our case study shows that the treatment of PJRT in young adults using cryoenergy can be successfully and safely conducted, especially after tachycardia recurrence following an initial radiofrequency ablation.

Left Atrial Appendage Closure With the New Occlutech® Device: First in Man Experience and Neurological Outcome.

AIMS: Percutaneous left atrial appendage closure (LAAC) is a valuable treatment option for stroke prevention in patients with atrial fibrillation and a HAS-BLED-Score ≥3. Determinants of procedural safety events and neurological outcome of the patients with the Occlutech device (OD) are not established yet. METHODS AND RESULTS: Between 2012 and 2016, 30 patients underwent LAAC using the OD. This is a prospective study. Neurological examination and transesophageal echocardiography was performed directly before and after the procedure and after 1, 3, and 12 months. The OC was successfully implanted in 28 of the 30 enrolled patients (93%). Two patients presented a hemodynamic relevant pericardial effusion. A leak <3 mm could be documented direct after implantation in 4 patients. After 3 months, there were only 2/4 patients with persistent LAA leakage with a maximum leakage of <3 mm. The correct position of the device was confirmed in 27/28 patients during 3-month follow-up. In 2 patients, there was a thrombus at the OC. In 12 patients, a transoesophageal echocardiography was performed after 12 months. All patients (12/12) showed a correct placement of the device. None of the patients developed a clinically apparent stroke or died during follow-up. CONCLUSION: In this uncontrolled, nonrandomized study, acute and 3-month follow-up success of LAAC using OD was high. No patient showed significant neurological deficits.

Atrial standstill in sinus node disease due to extensive atrial fibrosis: impact on dual chamber pacemaker implantation.

AIMS: Atrial standstill is characterized by the absence of atrial activity. We report about a series of cases, in which conventional atrial pacemaker lead implantation in patients with symptomatic sinus node disease failed due to lack of excitable right atrial tissue, thus, prompting the diagnosis of atrial standstill. We hypothesized that mapping of the atria with subsequent identification of myocardium still amenable to atrial pacing would allow dual chamber pacemaker implantation. METHODS AND RESULTS: In four patients, atrial lead implantation failed. In these patients, spontaneous or fibrillatory electrical activity was absent but the atria could not be captured despite high stimulation voltages at conventional atrial sites. We suspected partial or complete atrial standstill and subsequently confirmed this hypothesis by conventional (n = 1) or electroanatomical mapping (n = 3). Areas of fibrotic tissue were present in all patients as identified by lack of spontaneous electrical activity and inability of local electrical capture via the mapping catheter. Surviving atrial tissue, which could be electrically captured with subsequent conduction of activity to the atrioventricular (AV) node, was present in three patients. Successful targeted atrial lead implantation at these sites was achieved in all these patients. Isolated sinus node activity without conduction to the atria was found in one patient. CONCLUSION: Partial atrial standstill may be present and prevent atrial lead implantation in patients with sinus node disease. In these patients, recognition of partial atrial standstill and identification of surviving muscular islets with connection to the AV node by mapping studies may still allow synchronous AV sequential pacing.

[A series of cases--too old for a pacemaker?]. / Eine Case Serie--Zu alt für einen Schrittmacher?

We report three patients with an age above 90 years presented with symptomatic bradycardia and higher grade AV block in our clinic. The oldest patient was 100 years. All three patients could be supplied safely and without complications with a dual chamber pacemaker. Our case series shows that a dual chamber pacemaker implantation is safe and feasible in patients in very advanced age. A surgical management with local anesthetic (lidocaine), fentanyl and midazolam in individual cases is possible. This and a short hospital stay reduce the risk of delirium. It is a group of patients, which will increase in the future and requires more intensive care than the standard pacemaker patient.

Electromagnetic interference with implantable cardioverter-defibrillators at power frequency: an in vivo study.

BACKGROUND: The number of implantable cardioverter-defibrillators (ICDs) for the prevention of sudden cardiac death is continuing to increase. Given the technological complexity of ICDs, it is of critical importance to identify and control possible harmful electromagnetic interferences between various sources of electromagnetic fields and ICDs in daily life and occupational environments. METHODS AND RESULTS: Interference thresholds of 110 ICD patients (1-, 2-, and 3-chamber ICDs) were evaluated in a specifically developed test site. Patients were exposed to single and combined electric and magnetic 50-Hz fields with strengths of up to 30 kV·m⁻¹ and 2.55 mT. Tests were conducted considering worst-case conditions, including maximum sensitivity of the device or full inspiration. With devices being programmed to nominal sensitivity, ICDs remained unaffected in 91 patients (83%). Five of 110 devices (5%) showed transient loss of accurate right ventricular sensing, whereas 14 of 31 (45%) of the 2- and 3-chamber devices displayed impaired right atrial sensing. No interference was detected in 71 patients (65%) within the tested limits with programming to maximum sensitivity, whereas 20 of 110 subjects (18%) exhibited right ventricular disturbances and 19 of 31 (61%) subjects exhibited right atrial disturbances. CONCLUSIONS: Extremely low-frequency daily-life electromagnetic fields do not disturb sensing capabilities of ICDs. However, strong 50-Hz electromagnetic fields, present in certain occupational environments, may cause inappropriate sensing, potentially leading to false detection of atrial/ventricular arrhythmic events. When the right atrial/right ventricular interferences are compared, the atrial lead is more susceptible to electromagnetic fields. CLINICAL TRIAL REGISTRATION URL: http://clinicaltrials.gov/ct2/show/NCT01626261. Unique identifier: NCT01626261.

[Recurrent microdislocation of pacemaker leads due to an aortic aneurysm of the aorta ascendens]. / Rezidivierende Mikrodislokationen von Schrittmachersonden aufgrund eines Aortenaneurysmas der Aorta ascendens.

We report about a 79 years old female patient which was admitted due to a symptomatic AV block 3rd degree. The coronary angiography excluded a coronary artery disease and the echocardiography revealed a normal left ventricular systolic function. Therefore a dual-chamber pacemaker was implanted. Following two micro-dislocations of the right ventricular lead, which required operative revisions, a computed tomography of the heart was performed. This detected an aneurysm of the ascending aorta (5 cm maximum diameter) with compression of the superior caval vein. This case shows that a possible cause of recurrent micro-dislocations could be a pathological anatomy of the heart.

New Cerebral Microbleeds After Catheter-Based Structural Heart Interventions: An Exploratory Analysis.

Background Cerebral microbleeds (CMBs) are increasingly recognized as "covert" brain lesions indicating increased risk of future neurological events. However, data on CMBs in patients undergoing catheter-based structural heart interventions are scarce. Therefore, we assessed occurrence and predictors of new CMBs in patients undergoing catheter-based left atrial appendage closure and percutaneous mitral valve repair using the MitraClip System. Methods and Results We conducted an exploratory analysis using data derived from 2 prospective, observational studies. Eligible patients underwent cerebral magnetic resonance imaging (3 Tesla) examinations and cognitive tests (using the Montreal Cognitive Assessment) before and after catheter-based left atrial appendage closure and percutaneous mitral valve repair. Forty-seven patients (53% men; median age, 77 years) were included. New CMBs occurred in 17 of 47 patients (36%) following catheter-based structural heart interventions. Occurrences of new CMBs did not differ significantly between patients undergoing catheter-based left atrial appendage closure and percutaneous mitral valve repair (7/25 versus 10/22; P=0.348). In univariable analysis, longer procedure time was significantly associated with new CMBs. Adjustment for heparin attenuated this association (adjusted odds ratio [per 30 minutes]: 1.77 [95% CI, 0.92-3.83]; P=0.090). Conclusions New CMBs occur in approximately one-third of patients after catheter-based left atrial appendage closure and percutaneous mitral valve repair using the MitraClip System. Our data suggest that longer duration of the procedure may be a risk factor for new CMBs. Future studies in larger populations are needed to further investigate their clinical relevance. Clinical Trial Registration German Clinical Trials Register: DRKS00010300 (https://drks.de/search/en/trial/DRKS00010300); ClinicalTrials.gov : NCT03104556 (https://clinicaltrials.gov/ct2/show/NCT03104556?term=NCT03104556&draw=2&rank=1).

Prevalence of asymptomatic upper extremity venous obstruction in 302 patients undergoing first implantation of cardioverter defibrillator.

BACKGROUND: Little is known about the prevalence of upper extremity vein obstruction or anomalies in patients before first implantation of implantable cardioverter defibrillator (ICD). It remains unclear in which patients contrast venography is warranted before implantation procedure. METHODS: Results of clinical data and contrast venography of 302 consecutive patients scheduled for first ICD implantation were analyzed. RESULTS: Prevalence of upper vein obstruction was 6.6% (20/302 patients) in a typical patient population undergoing first ICD implantation. Age, left ventricular ejection fraction, underlying heart disease, prior open-heart surgery, or cardiopulmonary resuscitation were not predictors of obstruction. Patients with previous cardiac pacemaker implantation had a higher rate of obstruction, though this was not statistically significant (20% vs 15.7%, P = 0.54). Persistent left vena cava was found in 0.7%. CONCLUSION: There is no clinical parameter sufficient enough to predict upper extremity venous obstruction. Contrast venography may be considered in patients with previous pacemaker placement but should not be a routine diagnostic tool in unselected patients prior to first ICD-implantation procedure.

Hydrochlorothiazide therapy: impact on early recurrence of atrial fibrillation after catheter ablation?

BACKGROUND: Hypokalemia has been linked to electrocardiogram changes and afterdepolarization-mediated arrhythmias. However, the association between hypokalemia and atrial fibrillation (AF) has not been well studied. Hydrochlorothiazide (HCT) diuretic therapy was shown to be associated with hypokalemia in multiple studies. We aimed to determine whether HCT therapy is associated with early recurrence of AF after radiofrequency (RF) catheter ablation during a 3-month follow-up. METHODS: We performed a retrospective registry analysis of our internal AF ablation registry, containing 807 consecutive patients that underwent RF ablation for symptomatic AF. Propensity score matching was used to match 156 patients on HCT therapy with 156 controls. Furthermore, we performed propensity score matching between the first and the fourth quartile of baseline serum potassium (K) concentrations in the initial population (N.=807). RESULTS: We observed a small but statistically significant difference in baseline mean potassium levels between the HCT group and the control group (4.03 mmol/L vs. 4.19 mmol/L respectively, P=0.001). There was no difference in short term recurrence of atrial fibrillation in the HCT group compared to the propensity score matched control group (41.0% [N.=64] vs. 45.5% [N.=71], P=0.424). In the comparison between the first and the fourth quartile of baseline serum potassium values, no difference in AF recurrence (38.2% [N.=63] vs. 37.0% [N.=61], P=0.820) during a 3-month follow-up after ablation was observed between both groups. CONCLUSIONS: Patients on HCT therapy showed no difference in short term recurrence of AF after ablation compared to propensity matched controls.

The Beneficial Effects of Cardiac Rehabilitation.

Cardiac rehabilitation (CR) is a combined range of measures aimed at providing patients with cardiovascular disease with the optimum psychological and physical conditions so that they themselves can prevent their disease from progressing or potentially reversing its course. The following measures are the three main parts of CR: exercise training, lifestyle modification, and psychological intervention. The course of cardiac rehabilitation generally takes 3-4 weeks.

Catheter Ablation of Atrial Fibrillation: State of the Art and Future Perspectives.

PURPOSE OF REVIEW: Atrial fibrillation (AF), the most common sustained arrhythmia, is associated with high rates of morbidity and mortality. Maintenance of stable sinus rhythm (SR) is the intended treatment target in symptomatic patients, and catheter ablation aimed at isolating the pulmonary veins provides the most effective treatment option, supported by encouraging clinical outcome data. A variety of energy sources and devices have been developed and evaluated. In this review, we summarize the current state of the art of catheter ablation of AF and describe future perspectives. RECENT FINDINGS: Catheter ablation is a well-established treatment option for patients with symptomatic AF and is more successful at maintaining SR than antiarrhythmic drugs. Antral pulmonary vein isolation (PVI) as a stand-alone ablation strategy results in beneficial clinical outcomes and is therefore recommended as first-line strategy for both paroxysmal and persistent AF. While radiofrequency-based PVI in conjunction with a three-dimensional mapping system was for many years considered to be the "gold standard", the cryoballoon has emerged as the most commonly used alternative AF ablation tool, especially in patients with paroxysmal AF. Patients with persistent or long-standing persistent AF and with arrhythmia recurrence after previous PVI may benefit from additional ablation strategies, such as substrate modification of various forms or left atrial appendage isolation. New technologies and techniques, such as identification of the AF sources and magnetic resonance imaging-guided substrate modification, are on the way to further improve the success rates of catheter ablation for selected patients and might help to further reduce arrhythmia recurrence. CONCLUSIONS: Pulmonary vein isolation is the treatment of choice for symptomatic patients with paroxysmal and persistent drug-refractory AF. The reconnection of previously isolated pulmonary veins remains the major cause of AF recurrence. Novel ablation tools, such as balloon technologies or alternative energy sources, might help to overcome this limitation. Patients with non-paroxysmal AF and with AF recurrence might benefit from alternative ablation strategies. However, further studies are warranted to further improve our knowledge of the underlying mechanisms of AF and to obtain long-term clinical outcomes on new ablation techniques.

Comparison of cryoballoon and radiofrequency ablation of pulmonary veins in 40 patients with paroxysmal atrial fibrillation: a case-control study.

INTRODUCTION: Ablation of pulmonary veins (PV) is an established therapeutic option for patients with symptomatic drug-refractory paroxysmal atrial fibrillation (AF). Radiofrequency (RF) is currently the most widespread energy source for PV ablation. Cryothermal energy applied with a cryoballoon technique as an alternative has recently evolved. METHODS AND RESULTS: In a case-control setting, we compared 20 patients with paroxysmal AF who underwent their first PV ablation with the cryoballoon technique to 20 matched patients with conventional RF ablation. In the case of persistent electrical potentials after cryoballoon ablation, it was combined with ablation with a conventional cryocatheter. All patients performed daily event recording for 3 months after ablation procedure. Ablation parameters and success rate after 3 and 6 months were compared. In the cryoballoon group, the overall success rate was 55% (50% in the cryoballoon only group [14 patients] and 66% in the combination group [6 patients]), as opposed to the RF group with 45%. AF episode burden was lower after cryoballoon ablation. There was no significant difference between cryoballoon and RF ablation regarding procedure parameters. In the cryoballoon group, 3 phrenic nerve palsies occurred using the 23 mm balloon that resolved spontaneously. CONCLUSION: PV ablation with the cryoballoon technique is feasible and seems to have a similar success rate in comparison to RF ablation. Procedure- and fluoroscopy duration are not longer than in conventional RF ablation.

Velocity characteristics of atrial fibrillation sources determined by electrographic flow mapping before and after catheter ablation.

BACKGROUND: Electrographic-Flow-(EGF)-Mapping is a novel method to identify Atrial Fibrillation (AF) drivers. Sources of excitation during AF can be characterized and monitored. OBJECTIVE: The aim of this study was to evaluate the correlation between velocity of EGF around a respective AF source and its spatial variability (SV) and stability (SST). METHODS: 25 patients with AF were included in this study (persistent: n = 24, long-standing persistent: n = 1; mean age 70 ±â€¯8.3 years, male: n = 17). Focal impulse and Rotor-Mapping (FIRM) was performed in addition to pulmonary vein isolation. One-minute epochs of unipolar electrograms recorded via a 64-pole basket catheter in both atria were re-analyzed with EGF-Mapping. SST was calculated as the percentage of time in which a source was detected. RESULTS: AF sources identified with EGF-Mapping show a wide range of SV during 1 min covering between 0.12% and 38% of the recorded basket-catheter surface. The 12 atria where the sources showed highest temporal stability (TS; between 34% and 97% of 1 min recorded) and those 12 with the lowest TS (between 11 and 20%) differed significantly in their velocities (17.8 el/s vs 12.2 el/s; p < 0.01). In 11 atria ablation caused an average decrease of TS by 47% and of velocity by 27% while SV more than doubled. CONCLUSION: Less stable AF-sources with high spatial variability showed reduced excitation propagation velocity while stable AF sources displayed a high average velocity in their vicinity. Importantly, catheter ablation reduced stability of sources and velocity suggesting a role of these parameters in guidance of ablation. CONDENSED ABSTRACT: Electrographic Flow (EGF)-Mapping is a novel method to identify Atrial Fibrillation (AF) drivers based on modeling of an electrical potential surface and subsequent flow analysis. Sources of excitation during AF can be characterized and monitored. The aim of this study was to evaluate the correlation between velocity of EGF around a respective AF source and its spatial variability and stability. Less stable AF sources with high spatial variability showed reduced excitation propagation velocity while very stable AF sources displayed a high average velocity in their vicinity. Catheter ablation reduced stability of sources and velocity.

The use of a high-resolution mapping system may facilitate standard clinical practice in VE and VT ablation.

BACKGROUND: First experiences using a 64-electrode mini-basket catheter (BC) paired with an automatic mapping system (Rhythmia™) for catheter ablation (CA) of ventricular ectopy (VE) and ventricular tachycardia (VT) have been reported. OBJECTIVES: We aimed to evaluate (1) differences in ventricular access for the BC and (2) benefit of this technology in the setting of standard clinical practice. METHODS: Patients (pts) undergoing CA for VE or VT using the Intellamap Orion™ paired with the Rhythmia™ automated-mapping system were included in this study. For LV access, transseptal and retrograde access were compared. RESULTS: All 32 pts (29 men, age 63 ± 15 years) underwent CA for VE (17 pts) or VT (15 pts). For mapping of VE originating from the left ventricle (LV) in 10 out of 13 pts, a transaortic access was feasible. The predominant access for CA of VT was transaortic (5/7). Feasibility and safety seem to be equal. The total procedure time was 179.1 ± 21.2 min for VE ablation and 212.0 ± 71.7 min for VT ablation (p = 0.177). For VE, an acquisition of 1602 ± 1672 map points and annotation of 140 ± 98 automated mapping points sufficed to abolish VE in all pts. During a 6-month follow-up (FU) after CA for VE, a VE burden reduction from 18.5 ± 2.1% to 2.8 ± 2.2% (p = 0.019) was achieved. In VT pts, one patient showed recurrence of sustained VT episodes during FU. CONCLUSION: Use of a high-resolution mapping system for VE/VT CA potentially facilitates revelation of VE origin and VT circuits in the setting of standard clinical practice. Feasibility and safety of a venous, transaortic, transseptal, or a combined approach seem to be equal.