10-year follow-up of interventional electrophysiology: updated German survey during the COVID-19 pandemic.

INTRODUCTION: This study provides an update of survey-based data providing an overview of interventional electrophysiology over the last decade. Overall infrastructure, procedures, and training opportunities in Germany were assessed. METHODS: By analyzing mandatory quality reports, German cardiology centres performing electrophysiological studies were identified to repeat a questionnaire from 2010 and 2015. RESULTS: A complete questionnaire was returned by 192 centers performing about 75% of all ablations in Germany in 2020. In the presence of the COVID-19 pandemic, a total of 76.304 procedures including 68.407 ablations were reported representing a 38% increase compared to 2015. The median number of ablations increased from 180 in 2010 to 377 in 2020. AF was the most common arrhythmia ablated (51 vs. 35% in 2010). PVI with radiofrequency point-by-point ablation (64%) and cryo-balloon ablation (34%) were the preferred strategies. Less than 50 (75) PVI were performed by 31% (36%) of all centres. Only 25 and 24% of participating centres fulfilled EHRA and national requirements for training centre accreditation, respectively. There was a high number of EP centres with no fellows (38%). The proportion of female fellows in EP increased from 26% in 2010 to 33% in 2020. CONCLUSION: Comparing 2020, 2010 and 2015, an increasing number of EP centres and procedures were registered. In 2020, more than every second ablation was for therapy of AF. In the presence of an increasing number of procedures, training opportunities were still limited, and most centres did not fulfill recommended EHRA or national requirements for accreditation.

[How to approach the patient with supraventricular tachycardia in the EP lab: A systematic overview]. / Diagnostik bei supraventrikulären Tachykardien : Wie ist das Vorgehen im elektrophysiologischen Labor?

The term supraventricular tachycardia (SVT) summarizes those tachycardias involving the atrial myocardium along with the atrioventricular (AV) node. The prevalence is about 2.25 per 1000 (without atrial fibrillation and atrial flutter) and, therefore, SVT represents one of the most common group of arrhythmias besides atrial fibrillation encountered in the emergency department especially since they tend to recur until definite therapy. The clinical symptoms may include palpitations, anxiety, presyncope, angina, and dyspnea. Pharmacological therapy of these arrhythmias often fails. The present article deals with the differential diagnosis of SVT and also introduces a series of manuscripts that provide detailed insight into the differential diagnosis and treatment of these arrhythmias.

Nonanalyticity in scale in the planar limit of QCD.

Using methods of numerical lattice gauge theory we show that, in the limit of a large number of colors, properly regularized Wilson loops have an eigenvalue distribution which changes nonanalytically as the overall size of the loop is increased. This establishes a large-N phase transition in continuum planar gauge theory, a fact whose precise implications remain to be worked out.

[Is intraoperative ICD-testing still necessary?]. / Ist die intraoperative ICD-Testung noch nötig?

Intraoperative ICD-testing is traditionally performed in many hospitals in order to ensure reliable sensing, detection, and defibrillation of induced ventricular fibrillation. The technical progress of defibrillators allows rapid detection and delivery of high energy shocks which defibrillates effectively in the vast majority all patients at implant. This review describes arguments pro and contra of systematic testing of the defibrillation threshold in all patients. Many reasons argue against testing in all patients: experimental considerations, patients' specific and nonspecific factors, e.g., underlying severity of cardiac disease, ischemia, and medication, as well as factors specific to the ICD system, e.g., implanted type and location of electrodes and active cans. Finally, the testing method is very important, since it bears the risk of false negative test results because the a priori probability of a positive test result is >95%. Therefore, data from prospective randomized studies are necessary in order to abandon the tradition of ICD-testing on an evidence-based background.

Antihypertensive drug therapy and blood pressure control in men and women: an international perspective.

Cardiovascular death represents the single largest cause of mortality in women with 70% of deaths attributable to modifiable risk factors, such as hypertension. This analysis aims at evaluating, whether there are gender disparities in antihypertensive drug usage and blood pressure (BP) control. We included 18 017 patients with arterial hypertension from the International Survey Evaluating Microalbuminuria Routinely by Cardiologists in patients with Hypertension (I-SEARCH). The study was conducted between September 2005 and March 2006 in 26 countries, and data on patient demographics, cardiovascular disease and risk factors, BP, and cardiovascular drug treatment were collected. Mean systolic blood pressure (SBP) was 2.1 mm Hg higher in women (150.6+/-0.35 mm Hg, n=8357/18 017) than in men (148.5+/-0.35 mm Hg; P<0.0001, n=9526/18 017), whereas no difference in diastolic BP was seen (88.2+/-0.20 vs 88+/-0.20 mm Hg; P=0.198). Gender differences in SBP were more pronounced in diabetic as compared with non-diabetic patients (3.5 vs 1.7 mm Hg, n=4272 vs n=13 611; P<0.0001) and became evident at an age 55 years old. Overall BP-control rate was 33.6% in men and 30.6% in women (P<0.0001) and was lower in diabetic as compared with non-diabetic patients. In all, 30% of patients used one, 40% used two and 30% used > or = 3 drugs without gender differences. Response rates to different drug regimens appeared to be similar. However, women received more frequently thiazides and beta-blockers, and less frequently ACE-inhibitors as monotherapy. Major efforts are required to improve BP-management, especially in women.

Cardioversion of persistent atrial fibrillation by a combination of atrial specific and non-specific class III drugs in the goat.

OBJECTIVE: In electrically remodeled atria the effect of blockers of the delayed rectifier K+ current I(Kr) on repolarization is reduced, whereas the efficacy of 'early' class III drugs (I(Kur)/I(to)/I(Kach) blockers) is enhanced. We evaluated the electrophysiological and antifibrillatory effects of AVE0118, dofetilide, and ibutilide (alone and in combination) on persistent atrial fibrillation (AF) in the goat. METHODS AND RESULTS: The effects of separate and combined administration of AVE0118, dofetilide, and ibutilide were determined before and after 48 h of AF. AVE0118 alone markedly prolonged the atrial refractory period (400 ms cycle length) (AERP400) before and after 48 h of AF. The prolongation of AERP(400) by dofetilide and ibutilide, respectively, was reduced by AF from 22+/-2 to 7+/-2 ms (p<0.01) and 25+/-5 to 5+/-2 ms (p=0.01). Pre-treatment with AVE0118 restored the prolongation of AERP400 by dofetilide or ibutilide (to 20+/-3 and 30+/-6 ms; p<0.01). This effect was atrial specific since the QT-interval was not changed. The antifibrillatory action was evaluated in 10 goats that were in persistent AF for 57+/-7 days. Dofetilide (20 microg/kg/h) or ibutilide (4 mg/h) alone restored sinus rhythm in only 20% of the animals. AVE0118 (1, 3 and 10 mg/kg/h) [DOSAGE ERROR CORRECTED] terminated AF in 11, 30, and 60%, respectively. Additional infusion of I(Kr) blockers caused an additional number of cardioversions, resulting in a final cardioversion rate of 56, 80, and 100%, respectively. AVE0118 alone prolonged the AF cycle length (AFCL) while the conduction velocity during AF (CV(AF)) remained unchanged (70+/-1 vs. 68+/-2 cm/s; p=0.3). Addition of dofetilide or ibutilide caused a synergistic increase in AFCL and a slight increase in CV(AF) to 74+/-1 cm/s (p<0.001). The length of the reentrant trajectories increased from 7.6+/-0.3 (control) to 11.6+/-0.5 cm after AVE0118 alone (p<0.001) and 14.8+/-0.8 cm after addition of dofetilide or ibutilide (p<0.001). CONCLUSIONS: In electrically remodeled atria, blockade of I(Kur)/I(to)/I(KAch) restored the class III action of I(Kr) blockers. Persistent AF could be effectively cardioverted by infusion of a combination of AVE0118 and dofetilide or ibutilide. This antifibrillatory action was associated with an almost twofold lengthening of the intra-atrial pathways for reentry.

Large-N reduction in the continuum three-dimensional Yang-Mills theory.

Numerical and theoretical evidence leads us to propose the following: Three-dimensional Euclidean Yang-Mills theory in the planar limit undergoes a phase transition on a torus of side l=l(c). For l>l(c) the planar limit is l independent, as expected of a noninteracting string theory. We expect the situation in four dimensions to be similar.

[Atrial tachycardia, atrial flutter, atrial fibrillation: curative therapy by focal ablation in a pulmonary vein]. / Atriale Tachykardie, Vorhofflattern, Vorhofflimmern: Kurative Therapie durch fokale Ablation in einer Pulmonalvene.

We describe the case of a 50-year-old woman with the clinical diagnosis of cardiomyopathy associated with supraventricular tachycardia refractory to pharmacological treatment. The totally irregular tachyarrhythmia was the result of different episodes of atrial tachycardia, atrial flutter and atrial fibrillation that could be identified in the surface ECG. These findings and the patient's symptoms were all caused by a single focal tachycardia originating from the left upper pulmonary vein. Ablation of this focus represented a curative antiarrhythmic therapy also restoring a normalized ventricular function. Thus, an ablation of the AV node with consecutive pacemaker implantation could be prevented.

[Implantation of a dual chamber pacemaker-defibrillator (DDD-ICD) in a patient with hypertrophic obstructive cardiomyopathy]. / Implantation eines Zwei-Kammer-Schrittmacher-Defibrillators (DDD-ICD) bei einer Patientin mit hypertropher obstruktiver Kardiomyopathie.

A 70-year-old woman with severely symptomatic hypertrophic obstructive cardiomyopathy was unresponsive to drug treatment. She had recurrent ventricular tachyarrhythmias and syncope and was at high risk for sudden death; a dual chamber pacemaker defibrillator (DDD-ICD) was implanted. Her initial left ventricular outflow tract gradient was 80 mm Hg and fell to 40 mm Hg during dual-chamber pacing at an atrial ventricular delay of 140 ms. In the follow-up over six months she was asymptomatic with respect to angina pectoris; ventricular tachycardias could be successfully terminated by antitachycardia pacing or by shocks. A dual chamber pacemaker defibrillator is an important therapeutic option for patients with symptomatic hypertrophic obstructive cardiomyopathy and ventricular tachyarrhythmias.

Substitution of two histidine residues in YadA protein of Yersinia enterocolitica abrogates collagen binding, cell adherence and mouse virulence.

The plasmid-encoded surface protein YadA of Yersinia enterocolitica mediates binding to diverse extracellular matrix (ECM) proteins, adherence to epithelial cell lines, resistance to complement lysis, autoagglutination, and is required for mouse virulence. Using site-directed mutagenesis we attempted to analyse the relationship between structural domains and functions of YadA. In a first approach we could abrogate collagen binding by chemical modification of histidyl residues of YadA protein. This result prompted us to substitute histidyl residues (His) of conserved regions of YadA protein of Y. enterocolitica O8 by tyrosine residues using site-directed mutagenesis. Substitution of His-156 and His-159 (YadA-2 mutant) resulted in abrogation of binding to ECM proteins, of cell adherence, and in reduction of mouse virulence, whereas autoagglutination, serum complement resistance and oligomer formation remained unaffected. A striking result was obtained from the orogastric mouse-infection model: the YadA-2 mutant retained the ability to colonize the small intestine and to invade and multiply within the Peyer's patches but was impaired in colonizing mesenteric lymph nodes and spleen in comparison to the wild-type strain.