Anja Schade

Acute and early outcomes of focal impulse and rotor modulation (FIRM)-guided rotors-only ablation in patients with nonparoxysmal atrial fibrillation

BACKGROUND Focal impulse and rotor modulation (FIRM)-guided ablation targets sites that are thought to sustain atrial fibrillation (AF). OBJECTIVE The purpose of this study was to evaluate the acute and mid-term outcomes of FIRM-guided only ablation in patients with nonparoxysmal AF. METHODS We prospectively enrolled patients with persistent and long-standing persistent (LSP) AF at three centers to undergo FIRM-guided only ablation. We evaluated acute procedural success (defined as AF termination, organization, or ≥10% slowing), safety (incidence of periprocedural complications), and long-term success (single-procedure freedom from atrial tachycardia [AT]/AF off antiarrhythmic drugs [AAD] after a 2-month blanking period). RESULTS Twenty-nine patients with persistent (N = 20) and LSP (N = 9) AF underwent FIRM mapping. Rotors were presents in all patients, with a mean of 4 ± 1.2 per patient (62% were left atrial); 1 focal impulse was identified. All sources were successfully ablated, and overall acute success rate was 41% (0 AF termination, 2 AF slowing, 10 AF organization). There were no major procedure-related adverse events. After a mean 5.7 months of follow-up, single-procedure freedom from AT/AF without AADs was 17%. CONCLUSION In nonparoxysmal AF patients, targeted ablation of FIRM-identified rotors is not effective in obtaining AF termination, organization, or slowing during the procedure. After mid-term follow-up, the strategy of ablating FIRM-identified rotors alone did not prevent recurrence from AT/AF.

Higher incidence of esophageal lesions after ablation of atrial fibrillation related to the use of esophageal temperature probes

BACKGROUND Endoscopically detected esophageal lesions (EDELs) have been identified in apparently asymptomatic patients after catheter ablation of atrial fibrillation (AF). The use of esophageal probes to monitor luminal esophageal temperature (LET) during catheter ablation to protect esophageal damage is currently controversial. OBJECTIVE The purpose of this study was to investigate the impact of the use of esophageal temperature probes during AF catheter ablation on the incidence of EDELs. METHODS Eighty consecutive patients (mean age 63.8 ± 11.36 years; 68.8% men) with symptomatic, drug-refractory paroxysmal (n = 52, 65%) or persistent AF who underwent left atrial radiofrequency catheter ablation were prospectively enrolled. Posterior wall ablation was power limited (≤25 W). In the first 40 patients, LET was monitored continuously (group A), whereas no esophageal temperature probe was used in group B (n = 40 patients). Assessment of EDEL was performed by endoscopy within 2 days after radiofrequency catheter ablation. RESULTS Overall, 13 patients (16%) developed EDELs after AF ablation. The incidence of EDELs was significantly higher in group A than group B (30% vs 2.5%, P < .01). Within group A, patients who developed EDEL had higher maximal LET during AF ablation than patients without EDEL (40.97 ± 0.92°C vs 40.14 ± 1.1°C, P = .02). Multivariable logistic regression analysis revealed the use of an esophageal temperature probe as the only independent predictor for the development of EDEL (odds ratio 16.7, P < .01). CONCLUSION The use of esophageal temperature probes in the setting of AF catheter ablation per se appears to be a risk factor for the development of EDEL.

Pulmonary vein isolation with a novel endoscopic ablation system using laser energy

Pulmonary vein isolation (PVI) is the basis of all ablation techniques for paroxysmal atrial fibrillation. Performing conventional radiofrequency ablation for PVI is time consuming and sometimes challenging when using point-by-point applications to create continuous lesions. Small electrically conducting gaps evolving in the ablation lines may cause recurrences of atrial fibrillation or regular atrial re-entry tachycardias. Development of novel anatomically designed ablation catheters for PVI aim to facilitate the ablation procedure, to produce continuous and durable lesions with a limited number of ablation impulses and to reduce the complication rate. The endoscopic laser balloon ablation system (HeartLight® EAS, Cardiofocus Inc.) is the first system that allows direct visual guidance of energy delivery at the antral level of each pulmonary vein and uses a completely new energy source for ablation.

Exchanging Catheters Over a Single Transseptal Sheath During Left Atrial Ablation is Associated with a Higher Risk for Silent Cerebral Events

Background Silent cerebral events (SCE) have been identified on magnetic resonance imaging (MRI) in asymptomatic patients after atrial fibrillation (AF) ablation. Procedural determinants influencing the risk for SCE still remain unclear. Objective Comparing the risk for SCE depending on exchanges of catheters (ExCath) over a single transseptal sheath. Methods 88 Patients undergoing pulmonary vein isolation (PVI) only ablation using either single-tip or balloon-based technique underwent pre- and post-ablation cerebral MRI. Ablations were either performed with double transseptal access and without exchanging catheters over the transseptal sheaths (group 1: no ExCath) or after a single transseptal access and exchanges of therapeutic and diagnostic catheters (group 2: ExCath). Differences in regard to SCE rates were analyzed. Multivariate analysis was performed to identify factors related to the risk for SCE. Results Included patients underwent PVI using single tip irrigated radiofrequency in 41, endoscopic laser balloon in 27 and cryoballoon in 20 cases. Overall SCE were identified in 23 (26%) patients. In group 1 (no ExCath; N=46) 6 patients (13%) and in group 2 (N=42) 17 patients (40%) had documented SCE (p=0.007). The applied ablation technology did not affect SCE rate. In multivariate analysis age (OR 1.1, p=0.03) and catheter exchanges over a single transseptal sheath (OR 12.1, p=0.007) were the only independent predictors of a higher risk for SCE. Conclusions Exchanging catheters over a single transseptal access to perform left atrial ablation is associated with a significantly higher incidence of SCE compared to an ablation technique using different transseptal accesses for therapeutic and diagnostic catheters.

Cryoballoon ablation of paroxysmal atrial fibrillation within the dilated coronary sinus in a case of persistent left superior vena cava

Trigger sources of paroxysmal atrial fibrillation (PAF) are not limited to a pulmonary vein origin and may be achievable by cardiac vascular structures like the coronary sinus (CS), the vena cava superior and in some rare cases by a persistent left superior vena cava (LSVC). Cryoballoon ablation has been shown to be effective in pulmonary vein isolation. We report an unusual case of using this technique in the dilated CS in case of a persistent LSVC. A 64 year old patient presented PAF recurrences after cryo pulmonary vein isolation 4 months before. A maintaining pulmonary vein isolation could be demonstrated by transseptal mapping. Further bi-atrial mapping localized repetitive atrial trigger activity in a dilated CS proceeding to a LSVC. A cryoballoon was deployed in the CS target area and during cryoablation the triggered activity suspended. Ablation side effects were excluded by coronary angiography. During a follow up time of 8 months the patient has remained free of PAF recurrences. The current report underlines the importance of a patient-tailored ablation approach. Cryothermic balloon technology may be more applicable in delicate cardiac structures by developing new anatomically adapted balloon shapes and sizes.

Elektrischer Sturm in der Notaufnahme: Klinische Pfade

In patients with structural heart disease, occurrence of an electrical storm (ES) is associated with increased mortality acutely and during medium term follow-up. Depending on the underlying heart disease and baseline type of arrhythmia, different clinical pathways have to be followed to reach sustained freedom from ventricular arrhythmia recurrences. Trigger elimination, sympathetic blockade (initially using betablockers and sedation), antiarrhythmic therapy with amiodarone and catheter ablation, treatment of heart failure and invasive hemodynamic support are cornerstones of the treatment. We present an algorithm which may help to organize an optimized treatment for each ES patient, implementing invasive treatment options like coronary angioplasty, catheter ablation and invasive circulatory support. Further studies are necessary to evaluate medium term outcome of such a structured therapy.

Online Measurement of Microembolic Signal Burden by Transcranial Doppler during Catheter Ablation for Atrial Fibrillation—Results of a Multicenter Trial

Introduction Left atrial pulmonary vein isolation (PVI) is an accepted treatment option for patients with symptomatic atrial fibrillation (AF). This procedure can be complicated by stroke or silent cerebral embolism. Online measurement of microembolic signals (MESs) by transcranial Doppler (TCD) may be useful for characterizing thromboembolic burden during PVI. In this prospective multicenter trial, we investigated the burden, characteristics, and composition of MES during left atrial catheter ablation using a variety of catheter technologies. Materials and methods PVI was performed in a total of 42 patients using the circular-shaped multielectrode pulmonary vein ablation catheter (PVAC) technology in 23, an irrigated radiofrequency (IRF) in 14, and the cryoballoon (CB) technology in 5 patients. TCD was used to detect the total MES burden and sustained thromboembolic showers (TESs) of >30 s. During TES, the site of ablation within the left atrium was registered. MES composition was classified manually into “solid,” “gaseous,” or “equivocal” by off-line expert assessment. Results The total MES burden was higher when using IRF compared to CB (2,336 ± 1,654 vs. 593 ± 231; p = 0.007) and showed a tendency toward a higher burden when using IRF compared to PVAC (2,336 ± 1,654 vs. 1,685 ± 2,255; p = 0.08). TES occurred more often when using PVAC compared to IRF (1.5 ± 2 vs. 0.4 ± 1.3; p = 0.04) and most frequently when ablation was performed close to the left superior pulmonary vein (LSPV). Of the MES, 17.004 (23%) were characterized as definitely solid, 13.204 (18%) as clearly gaseous, and 44.366 (59%) as equivocal. Discussion We investigated the burden and characteristics of MES during left atrial catheter ablation for AF. All ablation techniques applied in this study generated a relevant number of MES. There was a significant difference in total MES burden using IRF compared to CB and a tendency toward a higher burden using IRF compared to PVAC. The highest TES burden was found in the PVAC group, particularly during ablation close to the LSPV. The composition of thromboembolic particles was balanced. The impact of MES, TES, and composition of thromboembolic particles on neurological outcome needs to be evaluated further. (Clinical Trial Registration: Deutsches Register Klinischer Studien, https://drks-neu.uniklinik-freiburg.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00003465. DRKS00003465.)

[Electrical storm in the emergency room: clinical pathways].

In patients with structural heart disease, occurrence of an electrical storm (ES) is associated with increased mortality acutely and during medium term follow-up. Depending on the underlying heart disease and baseline type of arrhythmia, different clinical pathways have to be followed to reach sustained freedom from ventricular arrhythmia recurrences. Trigger elimination, sympathetic blockade (initially using betablockers and sedation), antiarrhythmic therapy with amiodarone and catheter ablation, treatment of heart failure and invasive hemodynamic support are cornerstones of the treatment. We present an algorithm which may help to organize an optimized treatment for each ES patient, implementing invasive treatment options like coronary angioplasty, catheter ablation and invasive circulatory support. Further studies are necessary to evaluate medium term outcome of such a structured therapy.

Catheter ablation in patients with electrical storm: benefit of a network of cooperating clinics.

Catheter ablation has been shown to be an effective treatment for rhythm stabilization in patients with multiple ventricular arrhythmia episodes called electrical storm (ES). These procedures may be complex and are usually only performed in highly specialized and experienced centers. Still the optimum timing for catheter ablation in ES remains unclear.Early access to perform acute ablation should be considered in patients who are not rhythm stabilized with antiarrhythmic medical treatment. Also patients with hemodynamic compromise (cardiogenic shock) are candidates for an early interventional strategy. In specialized centers it is consensus to perform catheter ablation in these patients as early as eligible especially when considering a high early and late mortality without interventional management. Establishing a structured protocol for treatment and admission to EP centers has helped to further reduce pre-ablation mortality and may optimize treatment of ES. Large scale networking to optimize and structure access to experienced electrophysiology centers is of importance to create a basis for optimizing treatment strategies.ZusammenfassungDie Katheterablation bei Patienten mit gehäuften anhaltenden ventrikulären Arrhythmien (elektrischer Sturm, ES) hat sich als effektive Therapie herausgestellt, ein möglichst frühzeitiger Zugang zur Ablation erscheint gerade vor dem Hintergrund der hohen Spätmortalität und Rezidivraten sinnvoll. Der optimale Zeitpunkt für diese komplexe Prozedur ist allerdings noch unklar. Als komplexe Ablationsprozedur wird die Ablation bei ES nur in wenigen erfahrenen Zentren mit hoher Expertise durchgeführt. Initiale Versuche einer frühzeitigen Verlegung dieser Patienten in diese Zentren durch zuweisende Kliniken hat zu einer Verbesserung der Versorgung von Patienten mit ES geführt. Man kann ein frühzeitiges elektives Ablationsvorgehen noch innerhalb des stationären Erstaufenthalts nach Auftreten eines ES nach Rhythmusstabilisierung von einer Akut-Ablation, durchgeführt zur Rhythmusstabilisierung, unterscheiden.Innerhalb einer Klinik sollte eine Stufenplan zur Festlegung der Behandlungsstrategie erarbeitet werden. Aktuell wird in einem überregionalen Netzwerk von interventionellen elektrophysiologischen Zentren in Bayern ein Etappen-Therapie-Plan entwickelt, der unter anderem auch die Katheterablation als essentiellen Bestandteil beinhaltet. Im Rahmen der einzelnen teilnehmenden Zentren ist eine optimierte Versorgung der ES-Patienten mittels invasiver kardiologischer Therapieoptionen inklusive der interventionellen Elektrophysiologie initiiert. Somit wird versucht, flächendeckend diesen Patienten ein frühzeitiger Zugang zur Katheterablation zu ermöglichen.Insgesamt erscheint somit ein Netzwerk kooperierender Kliniken zur Optimierung und Strukturierung des Zugang zu erfahrenen elektrophysiologischen Zentren entscheidend als Basis einer optimierten Therapiestrategie.

Clinical Impact of the Microembolic Signal Burden During Catheter Ablation for Atrial Fibrillation: Just a Lot of Noise?

Microembolic signal detection by transcranial Doppler ultrasonography may be considered a surrogate for cerebral events during invasive cardiac procedures. However, the impact of the microembolic signal count during pulmonary vein isolation on the clinical outcome is not well evaluated. We investigated the effect of the microembolic signal count on the occurrence of new silent cerebral embolism measured by diffusion‐weighted imaging (DWI)‐magnetic resonance imaging (MRI), changes in neuropsychological testing, and the occurrence of clinical events during long‐term follow‐up after pulmonary vein isolation.