Endocardial ablation of ventricular tachycardia ablation in arrhythmogenic right ventricular cardiomyopathy aiming epicardial late potential abolition

Funding Acknowledgements

Type of funding sources: None.

Background

Catheter ablation is frequently needed to treat ventricular tachycardia (VT) in ARVC patients. Ablation aiming non-inducibility (NI) and late potential (LP) abolition has been shown to be effective1. Simultaneous endo-epicardial mapping demonstrate epicardial involvement in most VT2. However epicardial fat and vicinity of coronary artery may prevent effective epicardial ablation.

Aims

(a) evaluate endocardial-only ablation guided by epicardial late-potential recording (EA-ELP) to achieve LP abolition (LPA) and NI; (b) measure ablation-index(AI) values allowing epicardial LP suppression by endocardial ablation, as a surrogate for transmurality.

Methods

From 2019 to 2021 the authors (XW, EG) evaluated EA-ELP in ARVC patients patient referred for ablation. Our ablation protocol was previously described3. Endo and epicardial voltage mapping of the right ventricle (RV) were performed in sinus rhythm using 0.5-1.5 mV threshlods for endocardial scar and 0.5-1 mV for the epicardial. All LP were manually tagged. Programmed ventricular stimulation (PVS) was performed till S4 from the RV apex and other sites, all inducible tolerated VT were mapped. Endocardial ablation was performed with an irrigated tip catheter positioned in front of epi-LP recorded by a multi-electrode catheter aiming to eliminate or delay epi-LP as a surrogate for transmurality. For each lesion fulfilling the «transmurality criteria», the AI values were recorded. Remap was performed to validate LPA and NI was tested. Patient follow-up (FU) rely on telemonitoring in ICD-carriers and holter/exercise test for the others.

Results

11 patients were enrolled (9M/2F, mean age 45 years), 9 for VT recurrence (3 redo) and 2 for de novo VT. The median ICD therapy before ablation was 5/patient (mean 1.7). The clinical VT originated from the RV outflow tract (RVOT) in 5 patients, peritricuspid (PT) in 2, RV free wall (RFW) in 4. Substrate were more extended in the epicardium compared to the endocardium: epi-LP and scar surfaces were 42.5 cm2/118 cm2 versus 24.5 cm2/25.5 cm2 for the endocardium. In one patient, additional epicardial lesion was necessary to achieve LPA. The mean ablation duration was 3377 s. Remap showed LPA in all patients and PVS was negative in all (not tested in one due to hemodynamic instability). One patient presented retrosternal hematoma after ablation with spontaneous favorable outcome. Endocardial AI values allowing epi-LP abolition were 595 for the inferior wall, 625 in the RVOT, 604 for PT and 639 for RFW. During a mean FU of 12 months (median 16.5 mths), only one patient had VT recurrence.

Conclusion

Based on this case-series, EA-ELP appeared as a safe and effective method to treat VT in ARVC. EA-ELP ablation allowed VT suppression in 91 % of patients after an mean FU of 12 mths. The RV endocardial AI needed to suppress epi-LP ranged was between 595-639 and could be used as surrogate for transmurality in ARVC.

Impact of ablation index settings on pulmonary vein reconnection

PURPOSE

Ablation index (AI) is a radiofrequency lesion quality marker. The AI value that allows effective and safe pulmonary vein isolation (PVI) is still debated. We evaluated the incidence of acute and late PV reconnection (PVR) with different AI settings and its predictors.

METHODS

The Ablation Index Registry is a multicenter study that included patients with paroxysmal/persistent atrial fibrillation (AF) who underwent first-time ablation. Each operator performed the ablation using his preferred ablation catheter (ThermoCool® SmartTouch or Surround Flow) and AI setting (380 posterior-500 anterior and 330 posterior-450 anterior). We divided the study population into two groups according to the AI setting used: group 1 (330-450) and group 2 (380-500). Incidence of acute PVR was validated within 30 min after PVI, whereas the incidence of late PVR was evaluated at repeat procedure.

RESULTS

Overall, 490 patients were divided into groups 1 (258) and 2 (232). There was no significant difference in the procedural time, fluoroscopy time, and rate of the first-pass PVI between the two study groups. Acute PVR was observed in 5.6% PVs. The rate of acute PVR was slightly higher in group 2 (64/943, 6.8%, PVs) than in group 1 (48/1045, 4.6% PVs, p = 0.04). Thirty patients (6%) underwent a repeat procedure and late PVR was observed in 57/116 (49%) PVs (number of reconnected PV per patient of 1.9 ± 1.6). A similar rate of late PVR was found in the two study groups. No predictors of acute and late PVR were found.

CONCLUSION

Ablation with a lower range of AI is highly effective and is not associated with a higher rate of acute and late PVR. No predictors of PV reconnection were found.

Does left atrial appendage morphology have any impact on the results of percutaneous closure?

Introduction

Transcatheter left atrial appendage (LAA) occlusion is an alternative treatment in patients with atrial fibrillation (AF), high CHADSVASC Score and a contra-indication to anticoagulants. This retrospective cohort study aims to evaluate the impact of LLA morphology on procedure outcomes.

Methods

Patients from eight French centers who underwent left atrial appendage occlusion from February 2012 to January 2017 were included in this retrospective cohort study. LLA morphology was described by preoperative cardiac computed tomography (CT). Clinical data and Transoesophageal echocardiography (TEE) or CT results were collected during follow-up.

Results

Among 469 included patients, LAA morphologies were described in 215 cases 45.8%), 150 patients (70%) were implanted with Watchman devices, 57 (26%) with Amplatzer devices and 8 procedures (4%) failed. LAA Morphology was Chicken Wing (34%), Windsock (45%), cauliflower (18%) and 3% had another morphology including Cactus.

There was no difference in patient characteristics between the different morphology groups. Mean follow-up was 9.6±11 months, during which 190 patients underwent LAA imaging (TEE in 171 and CT in 19 patients). There was no significant difference in the failure rate (p=0.72), duration of the procedure (p=0.065), peri-device leak (p=0.83) device-related thrombus (p=0.96) and the occurrence of stroke (p=1) during follow-up.

Conclusion

LLA morphology did not influence complication occurrence after occlusion in this cohort.

Funding Acknowledgement

Type of funding source: None

P1021Low incidence of atrial tachycardia following ablation of low voltage areas in sinus rhythm for persistent atrial fibrillation

.  Background: Dedicated ablation strategies for persistent atrial fibrillation (AF) have shown a limited success rate with frequent atrial tachycardia (AT) occurrence. Recent studies suggest that atrial arrhythmogenic sites are related to tissular heterogeneities and increased fibrosis can be identified as reduced bipolar voltage areas.

. Purpose: Targeting low voltage areas (LVA) in addition to PVI may represent an efficient strategy for the ablation of persistent AF, and may limit the risk of AT recurrence.

. Methods: We prospectively included consecutive patients with symptomatic persistent AF. The ablation strategy consisted of the following steps: circumferential pulmonary vein isolation (CPVI), Sinus rhythm restoration by electrical cardioversion, voltage map performed in sinus rhythm. Complementary RFA was guided by low voltage areas (0.2-0.4 mV). Success was defined as freedom from AF/ atrial flutter or atrial arrhythmia at 12 months or more.

. Results:  101 patients (mean age: 62.5 +/- 10.4 years, men 73%) were included with persistent AF or long standing AF (7%). Procedure time was: 154 ± 25 min and fluoroscopy time: 184 ± 90 sec. Time of RFA was 44.7 +/- 12 min. Mean LA volume was 182 +/- 38 mL. LVA were found in 50 patients (49.5%). The distribution of these areas was:  30 anterior wall 29.7%), 21 septum (20.7%), 19 roof (18.8%), 5 inferior (4.9%), 11 left appendage (10.8%), 6 posterior (5.9%), 3 mitral isthmus (3%). RF ablation was realized for all LVA and homogenisation was attempt. After a single procedure at a mean FU of 12 months, 72.3% of patients were free of symptomatic AF. 27 patients had recurrence of atrial AF: 7 permanent, 15 persistent and 5 paroxysmal AF. Predictive factors of recurrence of AF were: long standing persistent AF, large left atrial volume (> 205 mL), shorts AF cycle length (< 168 ms) and reduce LEVF (< 45%). Atrial tachycardia occurred in 5 patients (4,9%). Mechanisms of AT were: typical cavo-tricuspid flutter in one patient, peri-mitral flutter in 2 patients, and atrial focal tachycardia (close to pulmonary veins) in 2 patients.

. Conclusion: These results suggest that PVI with complementary RF ablation guided on low voltage areas is an efficient strategy for symptomatic persistent AF, and reduce the recurrence of AT following this ablation strategy.

P999Major adverse events with percutaneous left atrial appendage closure in patients with atrial fibrillation in real life setting

Methods

We analysed data from all AF patients treated with Watchman or Amplatzer LAA closure according to European guidelines in 8 French cardiology departments. Antithrombotic management was decided for each patient on an individual basis. A Cox regression model was used for multivariable analysis of major adverse events. Yearly rate of ischemic stroke during follow-up was calculated and compared to that expected for a same risk score population. Yearly rate of bleeding was extrapolated from that reported with the HASBLED score.

Results

A total of 469 consecutive AF patients (299 males, 74.9±8.9 years old, mean CHA2DS2-VASc score 4.5±1.4, HASBLED score 3.7±1.0) received LAA closure from March 2012 to January 2017. There were 272 Watchman devices (58%) and 197 ACP devices (42%) implanted. At discharge, 36% received a single anti platelet therapy (APT), 23% received dual APT, 29% received OAC and no APT, 5% received OAC plus APT and 8% received no antithrombotic therapy. Mean follow up was 11.4 months (median 7, interquartile 3–22 months) during which 70 major adverse events (19 ischemic strokes, 18 major haemorrhages and 33 deaths) were recorded in 69 patients. The annual rate of ischemic stroke was 3.96%, which translates into a 13% relative risk reduction (95% CI −59 to 52%) as compared with the calculated stroke rate for similar CHA2DS2-VASc score after adjustment for exposure to APT and OAC. The annual rate of major bleeding in the study was 3.75%, which corresponds to a 48% relative risk reduction (95% CI 9 to 70%) as compared with the rate that would have been expected based on a comparable HAS-BLED score. Yearly rate of mortality was 7.4% (2.5 to 3 fold higher than in previous randomized trials) and the rate of non-cardiovascular death was 82%. None of the baseline characteristics was predictive of major adverse events, neither in univariate nor in multivariable analysis, which highlights the difficulty in identifying a risk of unfavourable outcome with simple tools.

Conclusions

AF patients treated with LAA closure may have a lower risk of stroke and bleeding events compared to their theoretical risk. However, our findings indicate that a high rate of major adverse events is observed in these patients during follow-up. This questions the suggested cost-effectiveness of the procedure (with models based on previous trials) for a real-life perspective. A better identification of patients with a relevant benefit of LAA closure is needed among those with long-term anticoagulation contraindication, both for an optimal management of each patient on an individual basis and for a global perspective with limited healthcare resources.

P2436Preliminary data from “LAA-Print French registry”: a large national multi-centric prospective registry evaluating a new preoperative approach based on 3Dprinted simulation in LAAC procedures

Aim

To demonstrate efficiency of 3D-printing simulation to predict LAAC procedural risk (failure, long procedure time, pericardial effusion or others serious adverse events (SAES) or inappropriate implantations)

Methods

Open study: Prospective and Consecutive.

Recruiting 150 patients in 16 centres (of 300 patients expected).

Start: Jan 18th, 2018.

Study Completion: Nov 1st, 2019.

ClinicalTrials ID: NCT03330210.

1. Cardiac CT prior to LAAC.

2. Industrial manufacture, laser sintering, of 3D-printed models including the whole LA cavity including interatrial thin septum and vena cava (using material TPU with adequat elasticity: shore 50).

3. LAAC Simulation based on 3Dprinted models using specific sheaths and prosthesis.

Prior to LAAC procedure each operator asses a risk score for procedural failure (low/moderate/high) based on real 3D printed LAAC simulation taking into account: trans-septal puncture site/sheath alignment with LAA ostium/device deployment and stability.

4. LAAC procedure TEE guided.

5. CT or TEE control M3 or M6.

Procedural outcomes according to risk Sc Low risk (N=63) Moderate risk (N=50) High risk (N=37) p<0.05 vs High risk Failure 1 (1.6%) 1 (2%) 10 (27%) * Recaptures ≥2 4 (6%) 5 (10%) 12 (32%) * Prosthesis ≥2 2 (3%) 1 (2%) 9 (24%) * Inappropriate implantation 0 6 (12%) 7 (19%) * SAES 2 (3%) 6 (12%) 12 (32%) * Pericardial effusion (pericardiocentesis) 2 (3%) 1 (2%) 4 (11%) * Haemorrhage (≥2 points) 0 2 (4%) 5 (13%) * Coronary syndrome 0 0 4 (11%) * Time (intra left atrium) min 21±10 29±16 50±25 * *p<0.05 vs High risk group according to prospective risk score.

LAAC simulation on 3D printed model

Conclusion

3D printing simulation accurately stratifies the risk of procedure according to LA anatomy. 3D printing may guide the procedure through verification of the transseptal puncture site and/or using a specific catheter shape and device. In case of high risk, a careful assessment of risk/benefice ratio is mandatory

Acknowledgement/Funding

AG2RFondation and Boston Scientific

Whole body [(18) F]fluorodeoxyglucose positron emission tomography imaging for the diagnosis of pacemaker or implantable cardioverter defibrillator infection: a preliminary prospective study

We studied the potential use of [(18) F]fluorodeoxyglucose ((18) F-FDG) whole body positron emission tomography (PET)-computed tomography for the diagnosis of device infection and extension of infection. Twenty-one patients with suspected device infection were prospectively included and compared with 14 controls free of infection. (18) F-FDG uptake on the box and on the leads was visually and quantitatively interpreted (using the maximal standard uptake value). The final diagnosis was obtained either from bacteriological data after device culture (n = 11) or by a 6-month follow-up according to modified Duke's criteria (n = 10). Ten patients finally showed infection on bacteriological study (n = 8) or during follow-up (n = 2). Sensitivity, specificity, positive predictive value and negative predictive value were, respectively, 80%, 100%, 100% and 84.6% on patient-based analysis (presence or absence of infection). They were 100%, 100%, 100% and 100% for boxes, but only 60%, 100%, 100% and 73% for leads. Quantitative analysis could be useful for boxes but not for leads, for which the presence of a mild hot spot was the best criterion of infection. The four false negatives on leads received antibiotics for longer than the six true positives (20 ± 7.2 vs. 3.2 ± 2.3 days, p <0.01). Although the study was not designed for this purpose, management could have been modified by PET results in six of 21 patients. (18) F-FDG PET imaging may be useful for the diagnosis of device infection, and could impact on clinical management. Interpretation of negative cases should be performed with caution if patients have received antibiotics.

[Perspectives in cardiology: evidence of efficacy in atrial fibrillation and hopes in acute coronary syndrome]

New antithrombotic drugs, antithrombin or anti Xa, will probably be very useful in cardiology. Two directions are interesting: in one hand atrial fibrillation, in which the unmet need concern drugs as effective as vitamine K antagonists but easier to use. On the other hand, in acute coronary syndrome the situation is different, there are many antithrombotic drugs available but there is still a place for innovative drugs which could provide a gain in terms of efficacy, but the hemorrhagic risk must remain acceptable. In atrial fibrillation, the RELY trial, performed in 18,113 patients has demonstrated, as compared to warfarin, a non inferiority of dabigatran at the dose of 110 mg BID and a superiority of dabigatran at 150 mg BID with a reduction of 34% of the primary endpoint, i.e.stroke and systemic embolism.

[Case report and review of a voluminous right atrial myxoma revealed by heart failure]

Right atrial myxoma is a rare disease and its clinical presentation is not specific. The usual mode of revelation is heart failure. The most frequent complications are pulmonary embolism and atrioventricular valve obstruction by the tumor. A 49-year-old woman was admitted to intensive care unit for heart failure. The echocardiogram showed a voluminous right atrial myxoma, appending to the interatrial septum. Its surgical excision under extracorporeal circulation was successfully performed. Histology confirmed the final diagnosis of myxoma. No complication was observed at 6 months follow-up.