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There is currently no agreement on the best method of assessing active left atrial (LA) emptying. This study evaluated the relative merits of cine- and velocity encoded (VENC) magnetic resonance imaging (MRI) for the assessment of active LA emptying. Total LA emptying volume (TLAEV) and active LA stroke volume (ALASV) were assessed in 107 consecutive patients using cine-MRI and transmitral flow measurements by VENC-MRI. The fraction of active LA emptying (ALAEF) was calculated as the ratio of ALASV to TLAEV. LA and left ventricular (LV) output were calculated by multiplying TLAEV and LV stroke volume by heart rate, respectively. Intra- and inter-observer variances were significantly larger for cine-MRI than for VENC-MRI measurements of ALASV (24.7 mL2 vs. 3.7 mL2 and 57.7 mL2 vs. 4.2 mL2; P

Aims The aim of this study was to assess the role of a non-pharmacological approach on the frequency of traumatic injuries and syncope recurrence in patients with vasovagal syncope and normal hearts. We report the experience in our syncope centre with a standardized education and teaching protocol for patients with vasovagal syncope. The treatment of vasovagal syncope is often complex and discouraging. Besides medical options, behaviour modification is a main component of therapy but has no statistical evidence to support its use. Methods and results Between January 1999 and September 2006, we prospectively enrolled all patients with vasovagal syncope. The patients were counselled about the benign nature of their disease. Specific recommendations were made according to a standardized education protocol established at our syncope centre. A pre-/post-study was conducted to investigate the effectiveness of our approach on syncope recurrence and frequency of injury as the study endpoints. Complete follow-up data were available from 85% of the study population (316 of 371) after a mean time of 710 ± 286 days (mean age 50 years; standard deviation ± 18 years, 160 female). Eighty-seven patients (27.5%) had a syncope recurrence with 22 suffering an injury during syncope. During the follow-up period, the syncope burden per month was significantly reduced from 0.35 ± 0.03 at initial presentation to 0.08 ± 0.02 ( P < 0.001). The frequency of traumatic syncope was significantly lower at the time of recurrence compared with the initial presentation (25 vs. 42%; McNemar's test P = 0.02). Conclusion A standardized education protocol significantly reduces traumatic injuries and syncope recurrence in patients with vasovagal syncope.

Aims Patients can expect a cure from atrial fibrillation (AF) with ablation. Procedural safety and success depend on patient comfort, compliance, and immobility. This is difficult to achieve with benzodiazepine and opiate boluses that are the mainstay of current practice. We sought to determine the safety and efficacy of propofol infusion sedation administered to patients without assisted ventilation for AF ablation. Methods and results Procedural data from 1000 consecutive patients undergoing AF ablation were analysed. Sedation with 2% propofol was used in all procedures without assisted ventilation and was administered, monitored, and controlled by electrophysiologists. Primary outcome measures were adverse sedative affects including (i) respiratory depression (SpO2 20 s) and (ii) persistent hypotension [systolic blood pressure (SBP)

Background Stepwise ablation is an effective treatment for persistent atrial fibrillation (AF), although it often requires multiple procedures to eliminate recurrent arrhythmias. Objective This study evaluated single- and multiple-procedure long-term success rates and potential predictors of a favorable single-procedure outcome of stepwise ablation for persistent AF. Methods This study comprised 395 patients with persistent AF (duration 16 months) undergoing de novo catheter ablation using the stepwise approach. Procedural success was defined as the absence of any arrhythmia recurrence. Patient characteristics and electrophysiological parameters were analyzed with respect to single- and multiple-procedure outcomes. Results After a follow-up of 27 ± 7 months, 108 (27%) patients were free of arrhythmia recurrences with a single procedure. After 2.3 ± 0.6 procedures, 312 (79%) patients were free of arrhythmia with concomitant antiarrhythmic treatment in 38% (23% on β-blocker). Female gender, duration of persistent AF, and congestive heart failure were predictive for the outcome after first ablation. However, the strongest predictors for single-procedure success were longer baseline AF cycle length (CL) and procedural AF termination. Moreover, procedural AF termination during the index procedure also predicted a favorable outcome after the last procedure, while the existence of congestive heart failure was associated with an increased risk for eventual arrhythmia recurrences. Conclusions Single-procedure long-term success is anticipated in approximately a quarter of patients undergoing de novo ablation of persistent AF. Baseline AFCL emerged as the strongest predictor of single-procedure success, while AF termination during index ablation predicts the overall outcome. However, an overall success rate of 79% is achievable with multiple procedures.

Catheter ablation of atrial fibrillation has evolved as a widely accepted therapy approach and is now also incorporated in the current guidelines.A major limitation consists of the limited three-dimensional visualization of the complex three-dimensional structures in the left atrium since most procedures have routinely been performed using fluoroscopy alone. Another unsolved problem is the limited durability of lesions sets performed with radiofrequency ablation and therefore somewhat disappointing long-term ablation results besides fluoroscopy exposition for patient and operator as required for safe catheter manipulation.In the recent years we have gained substantial insight with respect to arrhythmia mechanism. At the same time new techniques and developments have become available to improve catheter ablation results.The present article summarizes the available opportunities with respect to three-dimensional mapping including CT/MRI image integration and gives an overview of the robotic and magnetic systems available for catheter ablation.

Background— Termination of persistent atrial fibrillation (AF) can be achieved through ablation, with the majority of patients terminating to an atrial tachycardia (AT) and fewer directly to sinus rhythm (SR). We aimed to identify potential predictors for the existence of a substrate for AT on termination to SR. Methods and Results— We assessed 95 persistent AF patients (age, 60±10 years) who underwent catheter ablation to the end point of AF termination. Forty patients terminated directly to SR (SRterm) and 55 to ATs (ATterm). Compared with the ATterm group, the SRterm group were younger (56±10 versus 63±9 years, P =0.001), had shorter durations of AF before ablation (9±26 versus 14±20 months, P P =0.015), and longer baseline AF cycle lengths (178±23 versus 159±31 ms, P =0.005). However, AF cycle length was the sole independent predictor of direct termination to SR. The most frequent AF termination site in SRterm patients was the pulmonary veins (53%), whereas in ATterm patients this was within the left atrium (58%). After follow-up of 12±6 months, there was a trend toward a greater proportion of patients in SR among those who terminated directly to SR after a single procedure. The most frequent type of recurrence was paroxysmal AF in SRterm patients and AT in ATterm patients. Conclusions— Patients who terminate to SR through ablation without an intermediate AT are characterized by a less altered arrhythmogenic substrate. Baseline AF cycle lengths emerged as a sole independent predictor of a substrate for consecutive arrhythmias.

Robotic Remote Ablation for AF. Aims: A robotic navigation system (RNS, Hansen™) has been developed as an alternative method of performing ablation for atrial fibrillation (AF). Despite the growing application of RNS-guided pulmonary vein isolation (PVI), its consequences and mechanisms of subsequent AF recurrences are unknown. We investigated the acute procedural success and persistence of PVI over time after robotic PVI and its relation to clinical outcome. Methods and Results: Sixty-four patients (60.7 ± 9.8 years, 53 male) with paroxysmal AF underwent robotic circumferential PVI with 3-dimensional left atrial reconstruction (NavX™). A voluntary repeat invasive electrophysiological study was performed 3 months after ablation irrespective of clinical course. Robotic PVI was successful in all patients without complication (fluoroscopy time: 23.5 [12–34], procedure time: 180 [150–225] minutes). Fluoroscopy time demonstrated a gradual decline but was significantly reduced after the 30th patient following the introduction of additional navigation software (34 [29–45] vs 12 [9–17] minutes; P < 0.001). A repeat study at 3 months was performed in 63% of patients and revealed electrical conduction recovery in 43% of all PVs. Restudied patients without AF recurrence (n = 28) showed a significantly lower number of recovered PVs (1 (0–2) vs 2 (2–3); P = 0.006) and a longer LA-PV conduction delay than patients with AF recurrences (n = 12). Persistent block of all PVs was associated with freedom from AF in all patients. At 3 months, 67% of patients were free of AF, while reablation of recovered PVs led to an overall freedom from AF in 81% of patients after 1 year. Conclusion: Robotic PVI for PAF is safe, effective, and requires limited fluoroscopy while yielding comparable success rates to conventional ablation approaches with PV reconduction as a common phenomenon associated with AF recurrences. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1079-1084)

Catheter ablation of atrial fibrillation (AF), particularly longer lasting AF, often requires extensive ablation within the atria and their annexed structures. Immediate procedural success is commonly defined as termination of AF during ablation. While this end point is associated with fewer AF recurrences and maintained sinus rhythm, recurrent atrial tachycardias are common and present a fresh challenge for the electrophysiologist. These atrial tachycardias are often more symptomatic than the initial AF, but are invariably more suited to mapping and ablation with an excellent prospect of maintained sinus rhythm.

Background— Atrial tachycardias (AT) often occur after ablation of long-lasting persistent AF (CAF) and are difficult to treat conservatively. This study evaluated mechanisms and success rates of conventional mapping and catheter ablation of recurrent ATs occurring late after stepwise ablation of CAF. Methods and Results— A total of 320 patients underwent de novo ablation of CAF using a stepwise ablation approach in 2006 to 2007 at our institution. This study comprised patients who presented with recurrent ATs at their first redo procedure after initial de novo CAF ablation. All procedures were guided by conventional mapping techniques exclusively. Sixty-one patients (63�10 years, 14 women) presented with their clinical AT at their redo procedure 7.7�4.4 months after initial de novo CAF ablation. A total of 133 ATs (2.2�0.9 per patient) were mapped. Forty-four (72%) were due to reentry; 17 (28%) were focal ATs. Reentry ATs were mainly characterized as roof and perimitral flutter (43% and 34%, respectively). Focal ATs mainly originated from the great thoracic veins (pulmonary veins: 41%, coronary sinus: 23%). Forty-five (74%) patients had conduction recovery of at least 1 pulmonary vein (mean, 1.2�0.8). Overall, 124 (93%) ATs could be ablated successfully. The mean procedure duration was 181�59 minutes, with a mean fluoroscopy time of 45�21 minutes. After a mean follow-up of 21�4 months, 50 (82%) patients were free of any arrhythmia recurrences after a single redo procedure. Conclusions— Although late recurrent ATs may have complex mechanisms, catheter ablation guided exclusively by conventional techniques is highly effective with excellent acute and long-term success rates.

Recently, significant progress has been made treating atrial fibrillation (AF) with catheter ablation emerging as an increasingly important technique. Electrical disconnection of the pulmonary veins (PV) is a widely accepted endpoint for interventional treatment of paroxysmal AF (PAF). According to the current guidelines, catheter ablation can be considered as a therapeutic option in patients who failed antiarrhythmic drug treatment for PAF. The procedural endpoint for PVI is achievement of permanent electrical isolation of the PVs, which in the vast majority of patients harbor triggered electrical activity inducing and maintaining PAF. The success rate of this approach in patients with PAF ranges between 60 and 80% after a single procedure and augments to > 80 % in patients undergoing a repeat procedure to abolish recovered PV connection. However, it is now evident that persistent or long-standing persistent AF may not be successfully treated by PVI alone since the majority of patients have AF maintaining substrate beyond the PV. From a pathophysiological perspective this is explained by structural and electrical remodeling of the atrial myocardium in patients with persistent AF. Therefore, it is today widely accepted that additional substrate modification is required to effectively address persistent AF using catheter ablation. It has been shown that a combined approach of PV isolation, ablation of fractionated atrial electrograms and application of lines to treat atrial macro-reentrant tachycardias ("stepwise approach") aiming for restoration of sinus rhythm is a favorable strategy to treat persistent AF. However, significant expertise is needed to accomplish all steps within these complex procedures. Therefore, catheter ablation for persistent AF cannot yet be considered "clinically established" and should only be performed in high volume centers. Additional data is needed to verify the beneficial effect of this strategy and determine "predictors" identifying patients profiting most from these ablation strategies. In patients with PAF, catheter ablation has emerged as an established therapy also in comparison to antiarrythmic drug treatment. Recent studies have shown that catheter ablation for PAF is superior to antiarrhythmic drug treatment with regard to mid-term suppression of any atrial arrhythmia. Overall, catheter ablation for AF has still to be considered as a symptomatic treatment since evidence for beneficial effects with regard to more robust clinical endpoints such as death, rehospitalization and ischemic cerebral events are not yet available.

Aims Electrocardiographic changes, e.g. arrhythmias causing syncope or palpitations, are often transient and therefore difficult to diagnose. Systematic and symptom-activated ECG recordings can increase diagnostic yield in such patients. We evaluated the diagnostic accuracy of a simple, leadless, patient-operated ECG device compared with a standard 12-lead ECG. Methods and results We recorded a standard 12-lead surface ECG and a patient-activated ECG in direct succession in 508 consecutive patients enrolled in four centres. All ECGs were analysed by a single, blinded observer. ECGs were analysable in 505 (99.4%) patients (66% male, age 61 ± 15 years, and body mass index 27 ± 4). Analysis of the patient-activated ECG adequately detected a normal ECG (sensitivity 91% and specificity 95%), atrial fibrillation (AF) (sensitivity 99% and specificity 96%), and even T-wave abnormalities (sensitivity 90% and specificity 75%). Diagnostic accuracy for atrioventricular nodal block was moderate (sensitivity 79% and specificity 99%). Continuous parameters correlated well: ( r 2 = 0.89 for heart rate, 0.83 for PR interval, 0.78 for QRS duration, and 0.89 for QTc). Conclusion Recordings made by this patient-operated ECG device allow to detect arrhythmias and other ECG changes with high accuracy compared with a standard ECG. It may help to improve accurate diagnosis of transient ECG changes such as paroxysmal AF in palpitations or other unexplained cardiac symptoms.

Vorhofflimmern tritt mit einer hohen Inzidenz bevorzugt am 2. und 3. postoperativen Tag nach Bypass- und Klappenoperationen sowie bei Intensivpatienten auf. Auch bei thoraxchirurgischen Eingriffen wie der videoassistierten Thoraxchirurgie, Lobektomie oder extrapleuraler Pneumonektomie kann Vorhofflimmern auftreten. Die Prophylaxe mit β-Blockern reduziert die Inzidenz von postoperativem Vorhofflimmern signifikant. Neu aufgetretenes Vorhofflimmern bei Intensivpatienten kann je nach hamodynamischer Stabilitat mittels Rhythmus- oder Frequenzkontrolle behandelt werden. Zur Frequenzkontrolle konnen β-Blocker oder Kalziumantagonisten verwendet werden. Amiodaron ist ein effektives und sicheres Medikament zur Konversion von Vorhofflimmern. Eine Konversion nach 48 h Dauer ohne effektive Antikoagulation sollte nur nach vorangegangenem Thrombenausschluss mittels transosophagealer Echokardiographie durchgefuhrt werden. Nach erfolgter Kardioversion muss auf eine effektive Antikoagulation geachtet werden, um thrombembolische Komplikationen zu vermeiden.

Background— Termination of chronic atrial fibrillation (CAF) can be achieved by catheter ablation using a stepwise approach. However, there are limited data on the contribution of the right atrium to the CAF process. Furthermore, the prognostic value of CAF termination remains unclear. Methods and Results— Eighty-eight patients (61�10 years of age) underwent de novo ablation of CAF in 2006 at our institution. The ablation procedure was performed sequentially in the following order: pulmonary vein isolation, defragmentation of the left atrium, coronary sinus, and right atrium. Attempted procedural end point was termination of CAF. Consecutive arrhythmias occurring after AF termination were mapped, and ablation was attempted. AF termination was achieved in 68 (77%) patients: in 37 (55%) patients it occurred in the left atrium, in 18 (26%) patients in the right atrium, and in 13 (19%) patients in the coronary sinus. In 54 patients, at least one redo was performed (total number of procedures: 154). After the first redo, another 30 patients were in sinus rhythm (total 63), 8 patients were in atrial tachycardia (AT), and 17 patients were in AF. Another 11 patients underwent a second redo. After a mean follow-up of 20�4 months, 71 (81%) patients were in sinus rhythm, 1 (1%) patient was in AT, and 16 (18%) patients were in AF. Patients with CAF termination had predominantly ATs as recurrent arrhythmias (83%), whereas those without mainly presented with recurrent CAF (85%). The overall success rate in patients with CAF termination was 95% compared with 5% of patients without CAF termination in 2 procedures (n=12). In almost all redo procedures attributable to AT, at least 1 AT during redo was documented previously. Conclusions— AF termination is a prognostic important end point of catheter ablation for CAF. Termination of AF was achieved in both atria and the coronary sinus, suggesting a biatrial substrate of CAF. Subsequent arrhythmias often recur during follow-up and, therefore, should be targeted for ablation.

Durch seinen Hausarzt wurde uns ein 47-jahriger Patient mit paroxysmalem Vorhofflimmern zugewiesen. Seit etwa 2 Jahren beklagte der Patient ein anfallsartiges Herzrasen mit unregelmasigem Charakter. Die Rhythmusstorungen traten etwa zwei- bis dreimal im Monat auf und hatten eine Dauer von mehreren Stunden (meist 3–5 h). Der Patient fuhlte sich hierunter deutlich beeintrachtigt. In einem Langzeit-EKG konnte ursachlich Vorhofflimmern diagnostiziert werden. An Vorerkrankungen bestand eine diskrete arterielle Hypertonie, die (auch zur Behandlung des Vorhofflimmerns) seit einigen Wochen mit einem β-Blocker (Metoprolol 47,5 mg/Tag) eingestellt war. Die weitere Medikation bestand aus Acetylsalicylsaure (ASS) 100 mg taglich. Der Patient stellte sich in unserer Rhythmusambulanz mit der Frage weiterer Therapieoptionen vor. Bei der Untersuchung zeigten sich ein unauffalliges Sinusrhythmus-EKG sowie ein echokardiographischer Normalbefund. Hinweise auf das Vorliegen einer koronaren Herzerkrankung (KHK) ergaben sich nicht, so dass wir den Patienten auf Flecainid (2 × 100 mg) einstellten und einen Wiedervorstellungstermin in 4 Monaten vereinbarten. Beim zweiten Besuch gab der Patient schon deutlich seltenere und kurzer anhaltende Vorhofflimmerepisoden an, jedoch seien die Beschwerden noch nicht ganzlich unterdruckt. Auserdem storte ihn die regelmasige Tabletteneinnahme. Wir besprachen mit dem Patienten die Therapieoption einer Pulmonalvenenisolation, fur welche der Patient sich nach Darlegung der Erfolgsrate und der moglichen Risiken entschied. 2 Monate spater fuhrten wir eine Pulmonalvenenisolation durch, das Flecainid wurde 3 Tage vor Aufnahme pausiert. Zu Beginn des Eingriffs wurde mittels Burst-Stimulation Vorhofflimmern induziert, welches bei Ablation der linken unteren Pulmonalvene in den Sinusrhythmus konvertierte. Alle Pulmonalvenen konnten erfolgreich isoliert werden, das Flecainid wurde abgesetzt. 1 Woche nach Ablation wurde mit einer effektiven Antikoagulation mit Marcumar begonnen (bis dahin erfolgte die Gabe von niedermolekularem Heparin). Bei der Wiedervorstellung zur Verlaufskontrolle 3 Monate nach Ablation berichtete der Patient, insgesamt noch drei Vorhofflimmerepisoden verspurt zu haben, jeweils wieder mit spontaner Terminierung nach wenigen Stunden. Mit dem Verdacht auf Pulmonalvenenleitungserholung bestellten wir den Patienten erneut zur interventionellen Behandlung ein. Hier zeigte sich, wie vermutet, eine Leitungserholung von zwei der vier Pulmonalvenen. Es erfolgte eine komplikationslose Reisolation der linken unteren und der rechten oberen Pulmonalvene. Abschliesend war kein Vorhofflimmern mehr induzierbar. Im Verlauf zeigte der Patient auch ohne antiarrhythmische Therapie 1 Jahr nach dem zweiten Eingriff keine weiteren Episoden von Vorhofflimmern mehr. Dies konnte in Langzeit-EKGs belegt werden. Die antihypertensive Therapie wurde aufgrund von Nebenwirkungen auf einen ACE-Hemmer umgestellt, das Marcumar konnte mittlerweile abgesetzt werden.

Conventional catheter ablation for common-type atrial flutter (AFL) is a widely established therapy but has not been compared with the use of a robotic navigation system (RNS) thus far.The purpose of this study was to investigate the feasibility of a new, nonmagnetic RNS with regard to safety, efficacy, and X-ray exposure to investigator and patient compared with the conventional ablation approach in patients with AFL.Fifty patients (65.7 +/- 9.3 years, 40 male) undergoing de novo catheter ablation for AFL were randomly assigned to conventional or RNS-guided cavotricuspid isthmus (CTI) ablation.Complete bidirectional isthmus block was achieved for all patients without occurrence of procedure-related complications. The fluoroscopy time and the investigator X-ray exposure (8.2 +/- 4.6 vs. 5.8 +/- 3.6, P = .038; and 8.2 +/- 4.6 vs. 1.9 +/- 1.1 minutes, P.001) as well as the mean radiofrequency (RF) duration and the energy delivered were significantly higher in the conventional than in the RNS group (321.7 +/- 214.6 vs. 496.4 +/- 213.9 seconds, P = .006; 8279 +/- 5767 vs. 16,308 +/- 6870 J, P.001, respectively). The overall procedure time in the RNS group was significantly longer than in the conventional group (79.2 +/- 30.6 vs. 58.4 +/- 17.7 minutes; P = .04) but significantly decreased comparing the first 10 with the last 10 patients in the RNS group (105.3 +/- 34.8 vs. 60.6 +/- 6.3 minutes; P = .003). Starting ablation during AFL, bidirectional block instantly after termination was observed in 90% of the RNS and 50% of the conventionally treated patients (P = .03).The present study demonstrates the safety and feasibility of RNS for performing CTI ablation in patients with common-type AFL for use in the clinical routine. As a result of the remote navigation, X-ray exposure and RF duration to achieve bidirectional block were significantly decreased and occurred more often immediately after AFL termination. These findings are consistent with increased catheter stability and RF application efficacy using RNS compared with conventional catheter manipulation.

Seit der Entdeckung, dass die fokale Triggerung aus den Pulmonalvenen (PV) die entscheidende Rolle bei der Entstehung der paroxysmalen Form des Vorhofflimmerns (PAF) spielt, hat die Katheterablation dieser Arrhythmie eine rasche Verbreitung erfahren. Die Elimination der PV-Leitungseigenschaft ist dabei heute das allgemein akzeptierte primare Ziel bei PAF und fuhrt in 60–85% der Falle nach der ersten Prozedur zur Freiheit von Vorhofflimmern (AF). Bei Wiederholung der Katheterablation liegen die Erfolgsraten bei > 80%. Gestutzt durch die aktuellen Leitlinien ist dies bei symptomatischen und medikamentos therapierefraktaren Patienten (nach Versuch mit einem Antiarrhythmikum) ein gezielt einsetzbares und in erfahrenen Zentren etabliertes Verfahren. Bei chronisch persistierendem Vorhofflimmern (CAF) hat es in den letzten 2 Jahren einen enormen Fortschritt durch die Einfuhrung einer neuen, schrittweisen Strategie gegeben. Hierbei werden die herkommlichen Ansatze (Pulmonalvenenisolation [PVI], Defragmentierung und ggf. lineare Lasionen) kombiniert und mit dem Ziel der Terminierung des AF durch die Ablation angewendet. Dabei ist die erste Prozedur auch oft nur der erste Schritt auf dem Weg zum Sinusrhythmus bei allerdings sehr guter Prognose nach Terminierung des Vorhofflimmerns (> 80% Sinusrhythmus). Uber die Halfte der Patienten bedarf mehr als nur einer Prozedur, welche dann oft die Behandlung konsekutiv auftretender atrialer Tachyarrhythmien zum Ziel hat. Aufgrund der limitierten Nachbeobachtungszeit sowie des zeitlichen Aufwands, der mangelnden Ubertragbarkeit und der moglichen Komplikationen ist die Katheterablation bei CAF derzeit noch nicht klinisch „etabliert“ und insbesondere beim Vorliegen einer Herzinsuffizienz als experimentell zu bezeichnen. Gerade deshalb ist es wichtig, in zukunftigen Untersuchungen Pradiktoren zu identifizieren, welche ein Fehlschlagen der Prozedur bei CAF vorhersagen (Grose des linken Vorhofs, Dauer des AF, atriale Zykluslange) und somit helfen, die Patientenauswahl zu verbessern. Fur PAF gilt es, die unbefriedigenden Ergebnisse bezuglich der hohen Rezidivrate nach der ersten Prozedur zu optimieren. Hier konnte die Anwendung neuer Strategien (z.B. Testung der PV-Leitung durch Adenosin) und Technologien (z.B. robotische Navigation) hilfreich sein.

Objectives Our purpose was to investigate the impact of short-lasting atrial fibrillation (AF) on the electrophysiological properties of the atria and pulmonary veins (PVs) in patients devoid of AF. Background The presence of AF is associated with electrical remodeling processes that promote a substrate for arrhythmia maintenance in the atria, which has been termed “AF begets AF.” However, it is unclear whether those electrical alterations also occur in the PVs. Methods Thirty-five patients with a left-sided accessory pathway and without a prior history of AF were included. After successful ablation, the effective refractory periods (ERPs) and conduction times of the right atrium (RA), left atrium (LA), and the PVs were determined. Afterwards, AF was induced and maintained for a period of 15 min. Thereafter, the stimulation protocol was repeated. Results At baseline, the PVs had significantly longer ERPs than the atria. After exposure to AF, the ERPs of both the atria and the PVs decreased significantly. The ERPs of the PVs, however, decreased by a significantly greater extent than the ERPs of the atria (PVs: 248 ± 27 ms vs. 211 ± 40 ms, p Conclusions New-onset, short-lasting AF creates electrical characteristics similar to those of patients with AF. However, these alterations are pronounced in the PVs compared with the atria, indicating that “AF begets AF in the PVs” (Electrophysiological Properties of the Pulmonary Veins; NCT00530608).

Pulmonary veins (PVs) are the predominant sources of paroxysmal atrial fibrillation (AF), and electrical PV isolation has become an established interventional treatment for patients suffering from AF. There are a few cases describing PV tachycardias; however, mechanisms of PV arrhythmogenicity resulting in PV tachycardias remain incompletely understood. We report on a patient who underwent PV isolation for paroxysmal AF, in whom a persistent PV tachycardia was observed within an isolated vein. This tachycardia was stable in nature and different pacing manoeuvres revealed electrophysiological features consistent with reentry (Lasso displaying the entire tachycardia cycle length, concealed entrainment, overdrive termination, and induction by programmed stimulation) as the underlying mechanism.

A 67-year-old man with a 5-year history of drug-refractory persistent atrial fibrillation (AF) lasting for 7 months prior to the procedure underwent radiofrequency (RF) catheter ablation. The initial AF cycle length (CL) in the coronary sinus (CS) was 162 ms. Ablation was started with isolation of the left pulmonary veins (PV) by creating a continuous linear lesion around the ipsilateral PVs in a distance of *1 cm proximally to the PV ostia. Electrical isolation was confirmed by a single circumferential mapping catheter (Lasso, Biosense-Webster, Diamond Bar, CA, USA) which was sequentially placed in the superior and inferior left PV. After electrical disconnection of the left PVs, accompanied by a slow dissociated rhythm in both PVs, isolation of the right PVs was attempted using the same technique. Initially, a long continuous circular lesion was deployed surrounding both right PVs. Afterwards, potential electrical sleeve conductions of both right PVs were specifically targeted by repeatedly replacing the Lasso catheter in the superior and inferior right vein. However, complete elimination of all PV potentials could only be achieved in the right inferior PV. In contrast, the right superior PV (RSPV) still demonstrated PV potentials with a CL shorter than CS–CL. Although a total of 18 min of RF has been applied in order to isolate the right PVs, apparently no elimination of PV potentials in the RSPV could be achieved. Since the very short CL of the RSPV (CL = 114 ms, Fig. 1) was suggestive for a driving role of this vein in the AF process, external electrical cardioversion was performed to clarify the earliest PV activation during sinus rhythm and, thereby, to facilitate electrical isolation of this potentially ‘‘culprit vein’’. However, no potentials could be demonstrated in the RSPV after cardioversion (Fig. 2). Furthermore, pacing from within the PV demonstrated RSPV exit block. Thus, this observation retrospectively reveals the presence of a persistent PV tachycardia in the electrically isolated RSPV coexisting with ongoing and independently operating AF in the atria. Since complete isolation was confirmed, AF was reinduced and the ablation procedure was continued using the stepwise ablation approach. This approach comprises PV isolation, bi-atrial defragmentation, defragmentation and/or electrical isolation of the coronary sinus and leftatrial linear ablation. The aim of the mapping and ablation process is to gradually eliminate AF sources as represented by an incremental increase of the overall AFCL resulting in AF termination either directly to sinus rhythm or to atrial tachycardia(s) which are targeted until achievement of sinus rhythm [1, 2].

Marfan syndrome (MFS) is a variable, autosomal-dominant disorder of the connective tissue. In MFS serious ventricular arrhythmias and sudden cardiac death (SCD) can occur. The aim of this prospective study was to reveal underlying risk factors and to prospectively investigate the association between MFS and SCD in a long-term follow-up.77 patients with MFS were included. At baseline serum N-terminal pro-brain natriuretic peptide (NT-proBNP), transthoracic echocardiogram, 12-lead resting ECG, signal-averaged ECG (SAECG) and a 24-h Holter ECG with time- and frequency domain analyses were performed. The primary composite endpoint was defined as SCD, ventricular tachycardia (VT), ventricular fibrillation (VF) or arrhythmogenic syncope.The median follow-up (FU) time was 868 days. Among all risk stratification parameters, NT-proBNP remained the exclusive predictor (hazard ratio [HR]: 2.34, 95% confidence interval [CI]: 1.1 to 4.62, p=0.01) for the composite endpoint. With an optimal cut-off point at 214.3 pg/ml NT-proBNP predicted the composite primary endpoint accurately (AUC 0.936, p=0.00046, sensitivity 100%, specificity 79.0%). During FU, seven patients of Group 2 (NT-proBNP ≥ 214.3 pg/ml) reached the composite endpoint and 2 of these patients died due to SCD. In five patients, sustained VT was documented. All patients with a NT-proBNP214.3 pg/ml (Group 1) experienced no events. Group 2 patients had a significantly higher risk of experiencing the composite endpoint (logrank-test, p0.001).In contrast to non-invasive electrocardiographic parameter, NT-proBNP independently predicts adverse arrhythmogenic events in patients with MFS.

Catheter ablation of atrial fibrillation has evolved as a widely accepted therapy approach and is now also incorporated in the current guidelines.A major limitation consists of the limited three-dimensional visualization of the complex three-dimensional structures in the left atrium since most procedures have routinely been performed using fluoroscopy alone. Another unsolved problem is the limited durability of lesions sets performed with radiofrequency ablation and therefore somewhat disappointing long-term ablation results besides fluoroscopy exposition for patient and operator as required for safe catheter manipulation.In the recent years we have gained substantial insight with respect to arrhythmia mechanism. At the same time new techniques and developments have become available to improve catheter ablation results.The present article summarizes the available opportunities with respect to three-dimensional mapping including CT/MRI image integration and gives an overview of the robotic and magnetic systems available for catheter ablation.

Intravenous Electrolytes Increase Success Rate of Cardioversion. Background: External biphasic electrical cardioversion (CV) is a standard treatment option for patients suffering from acute symptoms of atrial fibrillation (AF). Nevertheless, CV is not always successful, and thus strategies to increase the success rate are desirable. Objective: The purpose of this study was to evaluate the effect of intravenously administered K/Mg solution on the biphasic CV energy threshold and success rate to restore sinus rhythm (SR) in patients with AF. Methods: The study consisted of 170 patients with persistent AF. The patients were randomly assigned to undergo biphasic CV either with (n = 84) or without (n = 86) pretreatment with K/Mg solution. An energy step-up protocol of 75, 100, and 150 W (J) was used. Results: Biphasic CV of AF was effective in 81 (96.4%) patients in the pretreatment and 74 (86.0%) patients in the control group (P = 0.005). The effective energy level required to achieve SR was significantly lower in the pretreated group (140.8 ± 26.9 J vs 182.5 ± 52.2 J, P = 0.02). No K/Mg-solution-associated side effects such as hypotension or bradycardia were observed. Conclusion: Administration of K/Mg solution positively influences the success rate of CV in patients with persistent AF. Furthermore, significantly less energy is required to successfully restore SR and therefore K/Mg pretreatment may facilitate SR restoration in patients undergoing CV for AF. (J Cardiovasc Electrophysiol, Vol. 23, pp. 54-59, January 2012)

Growing attention has been recently paid to the assessment of active LA emptying in patients after ablation of atrial fibrillation. Measurements of active LA emptying are typically performed by echocardiography in clinical routine. However, little is known about the role of cardiac MRI for this purpose. The present study evaluated the relative merits of biplane long-axis cine- and VENC-MRI for the assessment of active LA emptying.

The presence of reduced LAA flow velocities indicates patients who are prone to thrombus formation in the LAA and therefore being at high risk for subsequent cardioembolic stroke. LAA flow velocities are typically assessed by TEE in clinical routine. VENC-MRI is an established tool for the quantification of transvalvular flow, but the feasibility of LAA flow measurements by VENC-MRI has not been studied so far.

Aims We investigated the feasibility of real-time magnetic resonance imaging (RTMRI) guided ablation of the cavotricuspid isthmus (CTI) by using a MRI-compatible ablation catheter. Methods and results Cavotricuspid isthmus ablation was performed in an interventional RTMRI suite by using a novel 7 French, steerable, non-ferromagnetic ablation catheter in a porcine in vivo model ( n = 20). The catheter was introduced and navigated by RTMRI visualization only. Catheter position and movement during manipulation were continuously visualized during the entire intervention. Two porcine prematurely died due to VT/VF. Anatomical completion of the CTI ablation line could be achieved after a mean of 6.3±3 RF pulses (RF energy: 1807±1016.4 Ws/RF pulse, temperature: 55.9±5.9°C) in n = 18 animals. In 15 of 18 procedures (83.3%) a complete CTI block was proven by conventional mapping in the electrophysiological (EP) lab. Conclusion Completely non-fluoroscopic ablation guided by RTMRI using a steerable and non-ferromagnetic catheter is a promising novel technology in interventional electrophysiology.

Reduced Fluoroscopy in PVI Using RN. Background: Recently, a nonmagnetic robotic navigation system (RN, Hansen-Sensei™) has been introduced for remote catheter manipulation. Objective: To investigate the influence of RN combined with intuitive 3-dimensional mapping on the fluoroscopy exposure to operator and patient during pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) in a prospective randomized trial. Methods: Sixty patients were randomly assigned to undergo PVI either using a RN guided (group 1; n = 30, 20 male, 62 ± 7.7 years) or conventional ablation approach (group 2; n = 30, 14 male, 61 ± 7.6 years). A 3-dimensional mapping system (NavX™) was used in both groups. Results: Electrical disconnection of the ipsilateral pulmonary veins (PVs) was achieved in all patients. Use of RN significantly lowered the overall fluoroscopy time (9 ± 3.4 vs 22 ± 6.5 minutes; P < 0.001) and reduced the operator's fluoroscopy exposure (7 ± 2.1 vs 22 ± 6.5 minutes; P < 0.001). The difference in fluoroscopy duration between both groups was most pronounced during the ablation part of the procedure (3 ± 2.4 vs 17 ± 6.3 minutes; P < 0.001). The overall procedure duration tended to be prolonged using RN without reaching statistical significance (156 ± 44.4 vs 134 ± 12 minutes, P = 0.099). No difference regarding outcome was found during a midterm follow-up of 6 months (AF freedom group 1 = 73% vs 77% in group 2 [P = 0.345]). Conclusion: The use of RN for PVI seems to be effective and significantly reduces overall fluoroscopy time and operator's fluoroscopy exposure without affecting mid-term outcome after 6-month follow-up. (J Cardiovasc Electrophysiol, Vol. 21, pp. 6–12, January 2010)

Interventional treatment for atrial fibrillation (AF) has been introduced as a therapeutic option soon after the pulmonary veins (PV) have been discovered as the dominant sources of paroxysmal atrial fibrillation (PAF). Elimination of PV conduction is the initial goal during catheter ablation in this setting. The success rate after the initial procedure varies between 60% and 85%, with80% after subsequent interventions. Supported by the current guidelines, interventional treatment of AF is indicated in case of symptomatic arrhythmias refractory to antiarrhythmic treatment. The introduction of the combined, stepwise approach has been another important breakthrough with regard to the treatment of chronic persistent atrial fibrillation (CAF). This strategy includes the combination of all conventional ablation strategies (pulmonary vein isolation [PVI], defragmentation, linear ablation) with the goal of AF termination by radiofrequency current. The first procedure for CAF treatment is quite frequently also only the first step toward stable sinus rhythm with a favorable outcome after AF termination (80% sinus rhythm). In more than half of the patients predominantly atrial arrhythmias other than AF have to be targeted in a second procedure. This approach is currently under clinical investigation and so far not "clinically established" due to the fact that it is a quite time-consuming and challenging procedure even in experienced centers. Future studies may help to identify predictors for procedure failure (e.g., left atrial size, AF duration, atrial cycle length) in order to improve patient selection. Additionally, it has to be underscored, that in PAF the relatively high recurrence rate after the first procedure still is the subject of further investigations. This aspect might be improved by the introduction of novel strategies (i.e., testing of concealed PV conduction after ablation with adenosine) or technologies (i.e., robotic navigation) for PAF ablation.

Aims Beneficial effects of atrial fibrillation (AF) ablation have been demonstrated in patients with congestive heart failure (CHF) and significantly impaired left ventricular ejection fraction (LVEF). However, the impact of pulmonary vein isolation (PVI) on cardiac function in patients with paroxysmal AF and impaired LVEF remains under discussion. This study aimed to evaluate the impact of PVI for paroxysmal AF on cardiac function in patients with impaired LVEF using cardiac magnetic resonance imaging (CMRI). Methods and results A total number of 70 patients with paroxysmal AF and episodes � 24 h were scanned on a 1.5-T-CMRI before and 6 months after PVI during sinus rhythm. End-diastolic volume, end-systolic volume, and LVEF were determined by epicardial and endocardial measurements. Patients were categorized into two groups regarding cardiac function as assessed by CMRI: group 1 patients (n ¼ 18) with an LVEF , 50% and patients with an LVEF . 50% (group 2, n ¼ 52). Group 1 patients demonstrated a significant lower success rate than patients of group 2 after a follow-up of 152+ 40 days (50 vs. 73%, P , 0.05). Cardiac magnetic resonance imaging in group 1 patients demonstrated a significant improvement in cardiac function after AF ablation (41+ 6v s. 51+ 12%, P ¼ 0.004), whereas group 2 patients did not show significant differences (60+ 6v s. 59+ 9%, P ¼ 0.22) after a 6 months follow-up. Conclusion Pulmonary vein isolation improves cardiac function in patients with paroxysmal AF and impaired LVEF. These data suggest that an impaired LV function can be partially attributed to AF with short-lasting paroxysms.

Aims Rhythm follow-up after catheter ablation of atrial fibrillation (AF ablation) is mainly based on Holter electrocardiogramm (ECG), tele-ECG or on patients symptoms. However, studies using 7-day Holter or tele-ECG follow-up revealed a significant number of asymptomatic recurrences. Thus, the aim of this study was to analyse continuous atrial recordings in pacemaker patients with an incorporated Holter function before and after AF ablation in order to determine all AF recurrences and thereby the ‘real’ success rates. Methods and results The study comprised 37 patients (64.6 ± 10 years) with prior pacemaker/implantable cardioverter defibrillator (ICD) implantation including an atrial Holter function referred for AF ablation. Holter data were obtained and correlated to patients’ symptoms before and every 3-month after AF ablation. AF recurrence was defined as an atrial high frequency episode of less than 330 ms (180 b.p.m.) lasting longer than 30 s. The ablation procedure consisted of pulmonary vein isolation (PVI) in patients with paroxysmal atrial fibrillation (PAF, n = 20) and additional substrate modification aiming arrhythmia termination in patients with persistent or inducible AF after PVI as well as in patients with a history of long-lasting persistent AF (PersAF, n = 17). The mean atrial Holter monitoring period was 7.4 ± 3.3 months before and 13.5 ± 4.2 months after ablation with an overall AF burden of 33.7% prior to ablation. During follow-up, AF burden decreased from 17.3–0.65% ( P = 0.001) in PAF patients and from 57.4 to 13.9% ( P = 0.024) in patients with PersAF. Complete AF freedom was observed in 85% (17 patients) of PAF patients and 59% (10 patients) in patients with PersAF. The absence of symptoms correlated well with documented freedom of AF. Conclusion In the present study we could show, that freedom from AF can be achieved by catheter ablation in a high percentage of patients even with PersAF. Continuous atrial monitoring reveals AF ablation success rates comparable with those assessed by clinical evaluation. Symptomatic freedom of AF correlated well with the actual freedom of AF at least in this highly symptomatic patient cohort.

AP localization can be predicted by analyzing the polarity of the delta wave, QRS polarity, and R/S ratio in patients with Wolff-Parkinson-White syndrome. However, the estimation of AP location is limited in patients with concealed pathways during atrioventricular reentrant tachycardias (AVRT). Thus, we analyzed retrograde P-wave polarity during orthodromic AVRT and developed an algorithm to predict the localization of concealed accessory pathways (AP).A total number of 131 patients with a single AP and inducible orthodromic AVRT were included. The initial 61 patients were analyzed retrospectively for algorithm development, whereas 70 patients were evaluated prospectively. The retrograde P-wave polarity was analyzed by subtracting the superimposing T-wave during orthodromic AVRT using custom-designed software. Four leads of the surface electrocardiogram (ECG) were identified to accurately distinguish AP locations assigned to four different regions around each AV annulus: I, aVR, aVL, and V(1). Lead V(1) was used to differentiate right (negative or isoelectric) from left (solely positive) APs. Retrograde P-wave in lead I was negative in left posterior APs exclusively and became more positive with an AP location shifting towards right anterior. P-wave polarity in lead aVR demonstrated a shift from a positive polarity from left APs to isoelectric in right APs. The opposite direction (shift from positive to isoelectric) was observed for lead aVL. The subsequently developed algorithm for concealed AP localization using these surface ECG leads demonstrated a high sensitivity, specificity, and positive predictive value particularly for common AP localizations (left posterior and inferior, and right septal) when applied in a prospective fashion.Concealed AP localization can be accurately predicted by the analysis of retrograde P-wave polarity during orthodromic AVRT using the algorithm derived from the presented study.

Our purpose was to investigate the impact of short-lasting atrial fibrillation (AF) on the electrophysiological properties of the atria and pulmonary veins (PVs) in patients devoid of AF.The presence of AF is associated with electrical remodeling processes that promote a substrate for arrhythmia maintenance in the atria, which has been termed "AF begets AF." However, it is unclear whether those electrical alterations also occur in the PVs.Thirty-five patients with a left-sided accessory pathway and without a prior history of AF were included. After successful ablation, the effective refractory periods (ERPs) and conduction times of the right atrium (RA), left atrium (LA), and the PVs were determined. Afterwards, AF was induced and maintained for a period of 15 min. Thereafter, the stimulation protocol was repeated.At baseline, the PVs had significantly longer ERPs than the atria. After exposure to AF, the ERPs of both the atria and the PVs decreased significantly. The ERPs of the PVs, however, decreased by a significantly greater extent than the ERPs of the atria (PVs: 248 +/- 27 ms vs. 211 +/- 40 ms, p0.001; LA: 233 +/- 23 ms vs. 214 +/- 20 ms, p = 0.004; RA: 226 +/- 29 ms vs. 188 +/- 20 ms; p = 0.003). After AF exposure, the PVs demonstrated a significant conduction slowing whereas the atria did not (PVs: 125 +/- 33 ms vs. 159 +/- 37 ms, p0.001; LA: 129 +/- 26 ms vs. 130 +/- 24 ms, p = NS; RA: 192 +/- 36 ms vs. 196 +/- 32 ms, p = NS). Finally, AF was more frequently induced after the presence of AF, particularly by pacing in the PVs (14% vs. 49%, p = 0.001).New-onset, short-lasting AF creates electrical characteristics similar to those of patients with AF. However, these alterations are pronounced in the PVs compared with the atria, indicating that "AF begets AF in the PVs" (Electrophysiological Properties of the Pulmonary Veins; NCT00530608).

Introduction: Single procedure success rates of pulmonary vein isolation (PVI) in patients with paroxysmal atrial fibrillation (PAF) are still unsatisfactory. In patients with persistent AF adjunctive ablation of complex fractionated atrial electrograms (CFAE) is frequently used to improve outcome. We hypothesized that a subgroup of PAF-patients with sustained AF acutely after PVI might also benefit from additional CFAE-ablation. Methods: Overall 1032 consecutive patients received a first catheter ablation of strictly PAF between 08/2008-12/2012. In most patients AF was either not inducible or terminated during PVI. AF sustained after successful PVI in 61 patients (6%), who were randomized to either cardioversion (PVI-alone, n=30) or additional CFAE-ablation (PVI+CFAE, n=31). Primary endpoint was the reoccurrence of AF/AT. Results: Randomized patients had an AF-history of 62±8 months with max. episodes of 15±2 hours. Procedure-duration (126±6 vs 171±9 min), radiofrequency (RF) application- (44±3 vs 72±5 min) and fluoroscopy time (26±2 vs 40±2 min) were longer in PVI+CFAE (all p