Die diagnostischen Möglichkeiten der Radiologie in der Herzdiagnostik haben sich in den letzten 10 Jahren rasant weiterentwickelt. Das 640 Schichten-CT für die Koronarographie steht zur Verfügung, MRT-Untersuchungen mit 3 T-Geräten sind möglich.

La repolarisation précoce est une caractéristique électro cardiographique commune (1-5 % de la population générale). Une étude récente a montré que l'incidence de la repolarisation précoce (RP) est plus élevée chez les sujets ayant présenté une fibrillation ventriculaire (31 % des patients vs 5 % des contrôles). A ce jour, il est encore impossible de différencier les patients présentant un aspect de RP à risque parmi la population générale. L'existence de forme familiale de RP associée à des morts subites suggère un caractère héréditaire à cette pathologie. Une étude génétique a été réalisée sur une cohorte de 96 patients. Les gènes majeurs des troubles du rythme cardiaque et les genes codant les canaux ioniques impliqués dans la phase de repolarisation du potentiel d'action ventriculaire ont été exclus par séquençage chez ces patients. Les canaux potassiques ATP dépendant (KATP) sont fortement exprimés dans les cardiomyocytes. L'une des hypothèses émises est qu'une augmentation de 1-2 % de l'ouverture de ces canaux générerait un courant suffisant qui pourrait affecter la phase de repolarisation ventriculaire. Les canaux KATP sont composés de sous-unités canalaires Kir6.0 (KCNJ8 codant Kir6.1 ou KCNJ11 codant Kir6.2) et de récepteurs aux sulphonylurées SUR (ABCC8 codant SUR1 ou ABCC9 codant SUR2). L'approche gène-candidat a permis de mettre en évidence le variant rare p.S422L dans le gène KCNJ8 chez une jeune patiente présentant de nombreux épisodes de fibrillation ventriculaire (plus de 100) et une RP dans les dérivations inféro-latérales. Suite à ces premiers résultats, nous avons séquencés les autres sous-unités des canaux KATP. Ainsi, 5 variants ont été identifiés dans le gène ABCC9 : 4 variants faux-sens et une substitution d'un nucléotide dans un site d'epissage. L'enquête familiale et l'analyse fonctionnelle sont en cours pour ces patients. Plusieurs hypothèses physiopathologiques (augmentation du trafic membranaire, diminution de la sensibilité à l'ATP…) vont être testées afin de comprendre l'implication de ces variants sur le potentiel d'action ventriculaire. L'identification de 6 patients sur 96 (6.25 %) porteurs de variant dans les gènes codant les canaux KATP conforte l'hypothèse du rôle de ce courant dans le syndrome de repolarisation précoce.

Is onset of symptoms in AV nodal re-entrant tachycardia (AVNRT) and accessory pathway-mediated re-entrant tachycardia (AVRT) patients gender-specific?

Die kardiale Resynchronisation (CRT) mittels biventrikulärer Stimulation hat sich als Therapieoption in der Behandlung der therapie-refraktären schweren Herzinssuffizienz etabliert. Die zusätzliche Stimulation des linken Ventrikels führt zu einer relevanten klinischen und hämodynamischen Verbesserung. Die optimierte Programmierung dieser Stimulationssysteme kann allerdings ebenfalls einen modulierenden Effekt auf den Therapieerfolg haben. So zeigen invasiv und nicht-invasiv bestimmbare Parameter der kardialen Hämodynamik einen Vorteil der optimierten Programmierung der atrioventrikulären (AV) und ventrikulo-ventrikulären (VV) Verzögerungszeiten.

Cardiac resynchronization (CRT) has evolved as a therapeutic add-on tool in patients with refractory heart failure. Additional pacing of the left ventricle leads to relevant clinical and hemodynamic improvement. Optimized programming of these pacing systems may modulate therapeutic efficacy. Optimal atrio-ventricular (AV) and ventriculo-ventricular (VV) delay programming is documented to increase invasively and non-invasively determined parameters of cardiac hemodynamics. In this manuscript different options for determining optimal AV and VV delay are discussed and a pragmatic approach to optimize CRT programming is detailed. VV delay needs to be optimized as a first step of programming. Different techniques may estimate the individual need for sequential ventricular pacing. Especially electrocardiographic criteria during right and left ventricular pacing may approximate the time-delay for pre-excitation. Delay between aortic and pulmonic valve ejection can be determined using Doppler echocardiography may identify patients who benefit from sequential pacing. Optimizing AV delay is a domain of Doppler echocardiography where using a simple formula the AV delay that produces the best diastolic resynchronization of left atrial contraction and left ventricular ejection can be calculated.Using the above mentioned techniques a pragmatic, easy and fast method for increasing CRT performance can be established. In cases of worsening heart failure or relevant changes of left ventricular dimensions adaptions (re-optimization) of VV and AV delay may be needed.

A 37-year-old male patient with highly symptomatic and drug refractory paroxysmal atrial fibrillation underwent circumferential pulmonary vein ablation, using the electroanatomic mapping system (CARTO™, Biosense Webster Inc., Diamond Bar, CA, USA) and applying radiofrequency (RF) energy with an irrigated tip catheter (NaviStar™ ThermoCool®, Biosense Webster Inc.). The energy application time was 58.9 min and power was limited to 30 W at the posterior wall, as previously described.1 The patient was the 82nd in a series …

Drug Prescribing for Patients with Chronic Kidney Disease in General Practice: a Cross-Sectional Study

HISTORY:A 38 year old man suffered from exercise-induced reproducible dizziness and syncopes.INVESTIGATIONS AND DIAGNOSIS:During exercise testing a ventricular tachycardia at a rate of 300 beats/min was identified as the cause of the symptoms. Because of the ventricular morphology with inferior axis, left bunde branch block and the typical monomorphic repetitive characteristics, idiopathic adenosine-sensitive ventricular tachycardia was diagnosed.TREATMENT AND CLINICAL COURSE:Curative catheter ablation of the arrhythmogenic focus in the right ventricular outflow tract was performed. The patient has now been free of symptoms for more than two years. The characteristics of idiopathic ventricular tachycardia and the electrophysiological techniques are described.CONCLUSION:Idiopathic ventricular tachycardia is a rare cause of syncope in young patients without underlying heart disease and can be cured by catheter ablation. Exclusion of cardiac diseases, especially arrhythmogenic right ventricular cardiomyopathy, is of prognostic value.

BACKGROUND:In some patients with arrhythmias originating from the ventricular outflow tract, catheter ablation may be considered for curative treatment. The conventional ablation procedure may be limited particularly in cases with nonsustained arrhythmias. Only little information is available about three-dimensional electroanatomic mapping combined with the cooled radiofrequency (RF) catheter ablation technique in the treatment of such arrhythmias. PATIENTS AND METHODS:17 symptomatic and drug-refractory patients were included into this study. Using an electroanatomic mapping system (CARTO), activation mapping was obtained in twelve patients during ventricular tachycardia (VT) or ventricular ectopic beats. In five cases with nonsustained arrhythmias pace mapping during sinus rhythm was performed. The aim was to identify the precise localization of the arrhythmia origin and to abolish its activity by cooled ablation. RESULTS:Procedure time was 117 +/- 35 min, fluoroscopy time totaled 17 +/- 13 min. Ablation was performed with a mean of 7 +/- 5 ablation pulses. In 15 patients (88%) ablation of the clinical VT was acutely successful. During a follow-up of 9 +/- 9 months, two patients had a recurrence of the clinical VT. In one of these cases a successful reablation was performed. No major complications were observed. CONCLUSION:Electroanatomic mapping combined with focal cooled ablation strategy is a safe method to treat ventricular outflow tract arrhythmias effectively.

Drug Prescribing for Patients with Chronic Kidney Disease in General Practice: a Cross-Sectional Study

BACKGROUND AND AIM OF STUDY:The implantable cardioverter defibrillator (ICD) is the therapy of choice for patients with ventricular tachycardia (VT) after myocardial infarction. In some patients frequent ICD shocks occur, often resulting in clinical problems, if antiarrhythmic drugs insufficiently suppress them. Our aim was to describe electro-anatomical mapping and ablation techniques in patients with VTs, in which conventional strategy treatments have failed.PATIENTS AND METHODS:17 patients (69.5 +/- 8 years, 12 male) were included. During 3 months before ablation the number of ICD shocks was 21 +/- 8 (mean +/- SD). Using an electro-anatomical mapping system (CARTO), activation mapping was performed in 12 patients during hemodynamically tolerable, stable VT. In 5 cases with "non-mappable" VT only voltage mapping during sinus rhythm was obtained. The aim was to characterize the underlying scar tissue precisely in order to modify the substrate with an individual strategic linear lesion, thus preventing re-induction of VT.RESULTS:Procedure time was 184 +/- 9 minutes, fluoroscopy time totalled 19 +/- 9 minutes. Lesion lines were established with 13 +/- 9 ablation pulses. In 15 patients (88 %) acute ablation of the VT was successful. During a follow-up of 8 +/- 7 months, 2 patients had a recurrence of the VT. Two patients developed a VT with a different morphology. In another case ventricular fibrillation occurred. No major complications were observed.CONCLUSION:Electro-anatomical mapping combined with an individual linear ablation strategy is a safe and effective method to prevent symptomatic VT in patients after myocardial infarction.

OBJECTIVE:Plasma levels of brain natriuretic peptide (BNP) have been examined in studies on patients with persistent atrial fibrillation, both before and after electrical cardioversion. Studied patients often showed a comorbidity with congestive heart failure, which complicates interpretation of measured BNP values as a natriuretic peptide. The aim of this study was to examine plasma levels of N-terminal fragment pro-brain natriuretic peptide (NT-pro-BNP), which is the more stable but inactive cleavage product of pro-BNP in patients with atrial fibrillation, but normal left ventricular ejection fraction, before and after electrical cardioversion.PATIENTS AND METHODS:NT-pro-BNP plasma levels of 34 consecutive patients were measured before, shortly after and 11 days after electrical cardioversion. All patients showed a normal ejection fraction after echocardiographic or laevocardiographic criteria.RESULTS:At baseline, all patients showed elevated NT-pro-BNP compared to a healthy control group (1086 vs. 66.9 pg/ml, p<0.001). After a mean follow-up time of 11 days in patients with persistent restored sinusrhythm, NT-pro-BNP decreased from 1071 pg/ml at baseline to 300 pg/ml (p<0.001). In contrast, patients with recurrence of atrial fibrillation showed increased levels from 1570.5 pg/ml at baseline to 1991 pg/ml (p=0.13; n.s.). Recurrence of atrial fibrillation was independent from height of NT-pro-BNP levels at baseline (p=0.23).CONCLUSIONS:Atrial fibrillation in patients with a normal left ventricular ejection fraction is associated with elevated NT-pro-BNP plasma levels, which decrease when a persistent sinus-rhythm can be restored by electrical cardioversion. On the other hand, NT-pro-BNP seems to increase (n.s.) when recurrence of atrial fibrillation occurs. Finally, NT-pro-BNP is no valid predictor for long-term success of sinus-rhythm restoration by electrical cardioversion.

In this study, a series of 52 consecutive patients with atrial fibrillation from 1 institution underwent circumferential pulmonary vein ablation using an irrigated-tip catheter. The technique was safe, and 81% of the patients maintained sinus rhythm at 6 months. However, 1/3 of them required additional antiarrhythmic drug therapy. (C) 2004 by Excerpta Medica, Inc.

A female patient without underlying heart disease was highly symptomatic from short runs of atrial ectopy. Sustained atrial tachycardia or atrial fibrillation never occurred. Due to ineffective pharmacological therapy, catheter ablation combined with electroanatomic mapping (CARTO) was performed effectively. Characteristics of ectopic atrial tachycardia and the electrophysiological techniques are described.

A female patient without underlying heart disease was highly symptomatic from short runs of atrial ectopy. Sustained atrial tachycardia or atrial fibrillation never occurred. Due to ineffective pharmacological therapy, catheter ablation combined with electroanatomic mapping (CARTO(TM)) was performed effectively. Characteristics of ectopic atrial tachycardia and the electrophysiological techniques are described.

Eine herzgesunde Patientin stellte sich wegen einer ausgeprägten Symptomatik mit hohem Leidensdruck durch salvenartige atriale Extrasystolien ohne länger anhaltende Tachykardien oder intermittierendes Vorhofflimmern vor. Nach erfolgloser medikamentöser Therapie konnte eine kurative Katheterablation eines ektopen Fokus im rechten Vorhof unter Einsatz des elektroanatomischen Mappingsystems CARTO™ erfolgreich durchgeführt werden. Die Charakteristik ektoper atrialer Tachykardien und die elektrophysiologischen Techniken werden beschrieben.