[show abstract][hide abstract] ABSTRACT: Three-dimensional (3-D) mapping systems are of great value for the diagnosis and ablation of cardiac arrhythmias. If applied appropriately, 3-D mapping systems (3DM) can reduce fluoroscopy and procedural time. In general, two advanced mapping systems are currently in use: the CARTO™ system (Biosense Webster) uses ultralow-intensity magnetic fields to locate specially designed catheters in the heart chamber. Both, the activation sequence (activation map) and the local potential amplitude (voltage map) can be displayed. Additional applications are available: the SMARTTOUCH™ Catheter offers contact force registration, while CARTOMERGE™ enables integration of other imaging modalities into the map.The other commonly used mapping system is ENSITE NAVX™(Endocardial Solutions, St. Jude), which uses electrical current delivered across different pairs of patches on the body surface, and thereby creating voltage gradients. Thus, catheter tips and shafts in a 3-D field can be localized. Special applications of this system are the automated registration of complex fractionated atrial electrograms (CFAE) and a non-contact mapping function using the ENSITE ARRAY™ Mapping system. The EnSite-NavX™ system is not limited to the use of special sensor-equipped catheters. Basically, both systems are compatible with the remote navigation systems "NIOBE™" and "SENSEI®.
[show abstract][hide abstract] ABSTRACT: In recent years, ablation therapy has become the first-line treatment of modern electrophysiology in patients with cardiac arrhythmias. Today, cardiac magnetic resonance imaging (cMRI) is an important supportive imaging technique in the implementation of complex electrophysiological investigations and ablation therapy. In clinical routine, cMRI is used not only to generate accurate three-dimensional (3D) models of cavities of the heart but also for visualization of complex anatomical structures. The development of cMRI makes it possible to detect the underlying substrate of complex arrhythmias such as myocardial scar in patients with ventricular tachycardia or the structural remodeling of the left atrium in patients with atrial fibrillation. The opportunity of fusion of the different imaging modalities (e.g., fluoroscopy, cMRI) has become essential for the planning and the implementation of a safe ablation therapy. The possibility of direct visualization of induced lesions using cMRI after and in the long term after ablation can predict the success of therapy and detects potential complications. The continuous research in the field of cMRI and the development of MRI-compatible pacing and ablation catheters provided the basics for performing electrophysiological treatment in humans directly inside the MRI. The implementation of ablation using exact visualization of the anatomical substrate, precise catheter navigation and real-time visualization of lesions in cMRI promises to improve success rates and the safety of complex ablation treatment and may revolutionize electrophysiology in the future.
[show abstract][hide abstract] ABSTRACT: The ablation of simple and complex cardiac arrhythmias has become a first-line therapy in interventional cardiology and is mainly guided by conventional fluoroscopy. Cardiac magnetic resonance imaging (cMRI) allows exact three-dimensional (3D) visualization of complex anatomical structures and serves in the planning and implementation of ablation procedures. Post-procedural lesion visualization using cMRI can assess the success of ablation therapy and may distinguish potential complications. Performing ablation directly in the MRI scanner, with the option of anatomical substrate imagining, exact catheter navigation and real-time lesion visualization, holds the promise of improving success rates and safety in the interventional therapy of simple and complex arrhythmias.
[show abstract][hide abstract] ABSTRACT: Atrial fibrillation, which is associated with a worsening of congestive heart failure symptoms, an increased rate of stoke, and increased mortality, is still difficult to treat. New therapies must not only increase effectiveness, but also have to have an improved safety profile, in order to avoid sodium channel block in the ventricle of older patients with atrial fibrillation, and also prevent electrical and morphological remodeling. Dronedarone is less effective compared to amiodarone, but has a better side effect profile which leads to fewer discontinuations of treatment. The atrial ion channels are specifically blocked by a number of prospective antiarrhythmic substances. The most advanced is the testing of vernakalant (RSD1235), which primarily suppresses the I(Kur) current. Ranolazine is a new antianginal substance which influences the atrial ion channels and leads to a significant reduction of atrial and more specifically ventricular tachyarrhythmias. A number of other drugs are in development. They will lead to a better understanding of which form of atrial fibrillation can be best treated with which antiarrhythmic agent.
[show abstract][hide abstract] ABSTRACT: Since the implementation of cardiac resynchronization therapy (CRT) the prognosis of patients with severe heart failure has been improved owing to a reduction in morbidity and mortality rates, as several multicenter trials have shown. However, several patients treated by CRT still lack improvement or even deteriorate during therapy. In some of them, this might be due to the severity and progression of chronic heart failure. In others, the criteria for the indication of CRT and/or optimized device programming might have not been met. Thus, one important option to improve CRT outcome is to improve CRT patient selection. A lot of publications describing various methods identifying a positive or negative prediction of CRT have been released. In summary, decision making based on all these partly contradictory publications indicate a strong need for guidelines for the use of such expensive therapy. The purpose of this article is to give an overview of CRT and summarize the different methods and the limitations of CRT patient selection parameters. With the focus of the different guidelines, this article tries to give an appropriate overview and aid decision making in CRT patients, including a short view of possible new indications.
[show abstract][hide abstract] ABSTRACT: Intracardiac Echocardiography Guided Cryoballoon Ablation. Background: Cryoballoon ablation is increasingly used for pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). This new technique aims to perform PVI safer and faster. However, procedure and fluoroscopy times were similar to conventional RF approaches. We compared ICE plus fluoroscopy versus fluoroscopy alone for anatomical guidance of PVI.Methods: Forty-three consecutive patients with paroxysmal AF were randomly assigned to ICE plus fluoroscopy (n = 22) versus fluoroscopy alone (n = 21) for guidance of cryoballoon PVI. A “single big balloon” procedure using a 28 mm cryoballoon was performed. The optimal ICE-guided position of the cryoballoon was assessed by full ostial occlusion and loss of Doppler coded reflow to the left atrium (LA). Any further freezes were ICE-guided only without use of fluoroscopy or contrast media injection.Results: A total of 171 pulmonary veins could be visualized with ICE. 80% of ICE-guided freezes were performed with excellent ICE quality. Acute procedural success and AF recurrence rate at 6 months were similar in both groups (AF recurrence: ICE-guided = 27% vs Fluoroscopy = 33%; P = ns). Patients without ICE guidance had significantly longer procedure (143 ± 27 minutes vs 130 ± 19 minutes; P = 0.05) and fluoroscopy times (42 ± 13 minutes vs 26 ± 10, P = 0.01). The total amount of contrast used during the procedure was significantly lower in patients with ICE guidance (88 ± 31 mL vs 169 ± 38 mL, P < 0.001).Conclusion: Additional ICE guidance appears to be associated with lower fluoroscopy, contrast, and procedure times, with similar efficacy rates. Specifically, ICE allows for better identification of the PV LA junction and more precise anatomically guided cryoballoon ablations. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1202-1207, November 2010)
[show abstract][hide abstract] ABSTRACT: Vorhofflimmern ist nach wie vor ein schwieriges therapeutisches Problem, das mit einer Verschlechterung der Herzinsuffizienzsymptome,
einer erhöhten Schlaganfallquote und einer ansteigenden Mortalität verbunden ist. Neue Therapieansätze müssen nicht nur die
Effektivität erhöhen, sondern auch das Sicherheitsprofil verbessern, um bei älteren Patienten mit Vorhofflimmern eine Natriumblockade
im Ventrikel zu vermeiden, und ein elektrisches und morphologisches Remodeling zu verhindern. Dronedaron ist im Vergleich
zu Amiodaron weniger Wirksamkeit, verfügt aber über ein besseres Nebenwirkungsprofil und führt zu weniger Therapieabbrüchen.
Eine Reihe prospektiver antiarrhythmischer Substanzen blockieren spezifisch die atrialen Ionenkanäle. Am weitesten fortgeschritten
ist die Erprobung von Vernakalant (RSD1235), das hauptsächlich den IKur-Strom unterdrückt. Ranolazin ist eine neue antianginöse Substanz, die die atrialen Ionenkanäle beeinflusst und zu einer signifikanten
Reduktion atrialer und insbesondere ventrikulärer Tachyarrhythmien führt. Eine Reihe weiterer Medikamente befindet sich in
der Entwicklung. Sie werden zu einem besseren Verständnis darüber führen, welche Form des Vorhofflimmerns mit welchem Antiarrhythmikum
am besten therapiert werden kann.
Atrial fibrillation, which is associated with a worsening of congestive heart failure symptoms, an increased rate of stoke,
and increased mortality, is still difficult to treat. New therapies must not only increase effectiveness, but also have to
have an improved safety profile, in order to avoid sodium channel block in the ventricle of older patients with atrial fibrillation,
and also prevent electrical and morphological remodeling. Dronedarone is less effective compared to amiodarone, but has a
better side effect profile which leads to fewer discontinuations of treatment. The atrial ion channels are specifically blocked
by a number of prospective antiarrhythmic substances. The most advanced is the testing of vernakalant (RSD1235), which primarily
suppresses the IKur current. Ranolazine is a new antianginal substance which influences the atrial ion channels and leads to a significant reduction
of atrial and more specifically ventricular tachyarrhythmias. A number of other drugs are in development. They will lead to
a better understanding of which form of atrial fibrillation can be best treated with which antiarrhythmic agent.
KeywordsAntiarrhythmic drugs-Atrial fibrillation-Dronedarone-Vernakalant-Ranolazine
[show abstract][hide abstract] ABSTRACT: Die Ablation von einfachen und komplexen Herzrhythmusstörungen hat sich zu einer Standardtherapie der interventionellen Kardiologie entwickelt und wird in der Regel unter fluroskopischer Führung durchgeführt. In der klinischen Routine wird die kardiale Magnetresonanztomographie (cMRT) dazu eingesetzt, exakte 3-dimensionale (3-D) Darstellungen von komplexen anatomischen Strukturen anzufertigen und so der Planung und der Durchführung von Ablationsbehandlungen zu dienen. Die postinterventionelle Visualisierung von induzierten Läsionen mit Hilfe des cMRT vermag den Erfolg einer Ablationsbehandlung abzuschätzen und eventuelle Komplikationen zu erkennen. Die Durchführung von Ablationsbehandlungen direkt im MRT mit der Möglichkeit der genauen Visualisierung des anatomischen Substrats, der exakten Katheternavigation und der Echtzeitvisualisierung von Läsionen verspricht die Erfolgsraten und die Sicherheit von komplexen Ablationsbehandlungen zu verbessern.