Fostering diffusion of scientific contents of National Society Cardiovascular Journals:the new ESC search engine.

European Society of Cardiology (ESC) National Society Cardiovascular Journals (NSCJs) are high-quality biomedical journals focused on cardiovascular diseases. The Editors' Network of the ESC devises editorial initiatives aimed at improving the scientific quality and diffusion of NSCJ. In this article we will discuss on the importance of the Internet, electronic editions and open access strategies on scientific publishing. Finally, we will propose a new editorial initiative based on a novel electronic tool on the ESC web-page that may further help to increase the dissemination of contents and visibility of NSCJs.

Conflict of interest policies and disclosure requirements among European Society of Cardiology National Cardiovascular Journals.

Disclosure of potential conflicts of interest (COI) is used by biomedical journals to guarantee credibility and transparency of the scientific process. COI disclosure, however, is not systematically nor consistently dealt with by journals. Recent joint editorial efforts paved the way towards the implementation of uniform vehicles for COI disclosure. This paper provides a comprehensive editorial perspective on classical COI-related issues. New insights into current COI policies and practices among European Society of Cardiology national cardiovascular journals, as derived from a cross-sectional survey using a standardised questionnaire, are discussed.

Atrial fibrillation after radiofrequency ablation of atrial flutter: preventive effect of angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, and diuretics.

OBJECTIVES: To determine risk factors for the development of atrial fibrillation (AF) after atrial flutter (AFL) ablation; and to study the relation between AF development and periprocedural drug use. METHODS: AFL ablation was performed in 196 patients. The relation between AF occurrence and clinical, echocardiographic, and procedural factors and periprocedural drug use was analysed retrospectively by a Cox proportional hazard method. RESULTS: After a median follow up of 2.2 years, 114 patients (58%) developed at least one AF episode. Factors associated with AF development were the presence of preprocedural AF, a history of cardioversion, and the number of antiarrhythmic drugs used before the procedure. Use of angiotensin converting enzyme (ACE) inhibitors/angiotensin II receptor blockers and diuretics was significantly associated by univariate and multivariate analyses with less development of AF. CONCLUSIONS: A high proportion of patients develop AF after AFL ablation. The incidence of AF is related to pre-ablation AF and its persistence. ACE inhibitors/angiotensin II receptor blockers and diuretics seem to protect against AF.

Pericardial effusion and right-sided pneumothorax resulting from an atrial active-fixation lead.

We report on a patient in whom an active-fixation pre-shaped atrial lead caused perforation of the right atrial wall, pericardium and pleura, resulting in pericardial effusion and right-sided pneumothorax. Chest X-ray did not demonstrate protrusion of the atrial lead outside the cardiac silhouette but computed tomography visualized the tip of the helix of the atrial screw-in electrode outside the contours of the right atrial appendage touching the right upper lobe of the lung. The lead was repositioned with resolution of pericardial effusion and pneumothorax. Due to their proximity to the right lung, high anterolaterally positioned atrial screw-in leads carry a small but definite risk for right-sided pneumothorax.

Ablation of post-surgical intra-atrial reentrant tachycardia. Predilection target sites and mapping approach.

BACKGROUND: Atrial arrhythmias are a frequent complication of atrial surgery. The location of these tachycardias is very diverse due to the individual difference in the original anatomy, surgical corrections, and effects of atrial fibrosis. Nevertheless some recurrent patterns are emerging. METHODS AND RESULTS: Forty-five patients underwent 51 ablation procedures between September 1995 and March 2001 using conventional mapping and temperature-controlled ablation. A duadecapolar catheter was swept from anterior to posterior in the right (and/or left) atrium, allowing for rapid mapping followed by entrainment confirmation. Twenty-eight patients had corrected congenital heart disease, 17 surgery for acquired heart disease. One hundred and sixteen arrhythmias were found, 86 circuits were targeted, 81 with success (94%). Despite the heterogeneous anatomy, the same targets were often encountered: the posterior isthmus between the inferior vena cava and the tricuspid ring (62%), the gap between the inferior vena cava and the atriotomy scar (49%), and the region around the atriopulmonary connection in Fontans (two out of four patients). After a mean follow-up of 24 months, 13 patients had a recurrent arrhythmia (29%) after their last procedure. There was a significant association between the number of circuits found during the initial procedure and the likelihood of recurrent arrhythmias. CONCLUSION: Knowledge of anatomical predilection sites and mapping the right (and/or left) atrium with a 'sweeping Halo technique' allow for effective ablation of most post-surgical atrial tachycardias. Severely damaged atria with multiple arrhythmias may require 'preventive' ablation of all recognizable channels.

Effect of different pacing protocols on the induction of atrial fibrillation in a transvenously paced sheep model.

In different animal models rapid atrial stimulation led to a shortening and maladaptation to rate of the atrial effective refractory period (AERP). This atrial electrical remodeling resulted in an increased vulnerability to atrial fibrillation (AF). These experimental findings formed the rationale for a stringent pursuit of sinus rhythm in patients with AF, since this would prevent or reverse atrial remodeling. This study tested the hypothesis that a reduction of arrhythmia burden would lead to a decreased vulnerability for AF. Different rapid atrial pacing protocols in a sheep model were used. During 15 weeks, 13 animals were continuously rapid paced and 7 animals were intermittently burst-paced, resulting in rapid atrial activation during 100% versus 33 +/- 4% of the time, respectively. In the continuously paced group, 77% of the animals developed sustained AF (i.e., > 1 hour) versus only 29% in the burst-paced group (P < 0.05). However, there was no difference in mean AERP shortening over time, nor maximal AERP shortening per animal, between both protocols. Minimal AERP was 103 +/- 5 ms in the continuously paced group and 107 +/- 5 in the burst-paced group (P = NS). Significant changes could be identified in effect on P wave duration, AVN function, and atrial dilation. Conduction slowing was more pronounced in the continuously paced group with a maximal P wave duration of 136 +/- 4 ms in this group versus 116 +/- 5 in the burst-paced group (P < 0.05). In the continuously paced group, the right atrial area significantly increased from 2.5 +/- 0.1 cm2 at baseline to 4.2 +/- 0.2 cm2. In the burst-paced group there was no significant atrial dilatation (from 2.6 +/- 0.1 to 2.8 +/- 0.1 cm2). In conclusion, limiting atrial arrhythmia burden slowed the development of sustained AF in this sheep model. This was not mediated by a decreased influence on atrial refractoriness but seemed to be dependent on smaller changes in atrial conduction and dimensions.

The World Survey of Cardiac Pacing and Implantable Cardioverter Defibrillators: calendar year 1997--Europe.

The registry of the European Working Group on Cardiac Pacing (EWGCP) is based on the European Pacemaker Identification Card originally designed in July 1978. National registration centers collect the local data and send aggregated annual data to the EWGCP. For 1997, data were obtained from 2,887 hospitals in 20 European countries representing a population of 568 million. Across all participating countries, the median value for all implanted pacemakers was 378 per million population. For initial pacemaker implants, the median value was 290 per million population. Single chamber atrial pacing was important in Denmark, the Netherlands, Poland, Slovak Republic, Spain, and Sweden for the treatment of sick sinus syndrome. Dual chamber pacing accounted for < 50% of initial implants in only 5 of 14 countries for atrioventricular block, and in only 3 of 15 countries for sick sinus syndrome. In 7 of 15 countries, unipolar ventricular leads were used in > or = 50% of cases. In 6 of 14 countries, there was > 15% use of unipolar atrial leads. Nine of 13 countries frequently used atrial active-fixation leads. For the 1997 survey, ICD data were obtained from 16 countries. The total number of ICDs per million population was a median value of 14. Initial ICD implants per million population was 11. Only 3 of 16 countries implanted a total of 30 or more ICDs per million population. Pacing and ICD practices were dependent on the availability of medical and technical resources and influenced by economic constraints inherent in health care administration and insurance coverage patterns.

Paradoxical undersensing at a high sensitivity in dual chamber pacemakers.

In view of the evolving indications for device therapy in atrial arrhythmia the accurate detection of high rate atrial events is a necessity. In a sheep model of atrial fibrillation (AF) we observed a contradictory behavior of the Thera DR pacemaker. The pacemakers were programmed to deliver burst pacing on detection of sinus rhythm (SR). Paradoxically, progressively more inappropriate bursts were delivered during AF, at a higher sensitivity. This implied that the pacemaker interpreted AF as SR. We assessed the atrial detection of the Thera DR, Diamond, Saphir, and Marathon pacemakers during AF, in a sheep model and in vitro using a waveform generator. By counting the annotated atrial-sensed events reported by the pacemaker we charted the behavior of the pacemakers at different sensitivities. At a higher sensitivity both the Thera DR and the Diamond paradoxically reported fewer atrial events during AF. This behavior led to inappropriate mode switching and incorrect diagnostic data collection. It could be reproduced in vitro. The Marathon did not show this paradoxical undersensing in vivo or in vitro. This paradoxical undersensing at a high sensitivity is dependent on the amplitude of the input signal and could not be explained by an overlap of programmable timing parameters. It is caused by ringing of the atrial sensing amplifier. At high atrial rates and a high sensitivity the ringing of the repetitive atrial signal input results in blanking of the atrial amplifier. This observation may be relevant in the device management of patients with paroxysmal AF.

Different patterns of angiotensin II and atrial natriuretic peptide secretion in a sheep model of atrial fibrillation.

INTRODUCTION: It is well established that rapid atrial rates, as in atrial fibrillation (AF), cause atrial electrical and structural remodeling leading to the maintenance of AF. The role of neurohumoral changes in this pathophysiologic vicious circle remains unclear. METHODS AND RESULTS: We followed the concentrations of angiotensin II (AT II) and atrial natriuretic peptide (ANP) in a sheep model of AF. The sheep were atrially paced at 600 beats/min for 15 weeks. Electrophysiologic study was performed at regular intervals, and venous blood samples were taken. There was a slow increase in the vulnerability for AF. The cumulative incidence of sustained AF was 80% after 15 weeks of pacing. This increased vulnerability for AF was accompanied by atrial electrical remodeling and an increase in atrial pressure. AT II increased rapidly and stayed elevated: 17+/-4 pg/mL at baseline, and 40+/-11 and 39+/-7 pg/mL after 1 and 12 weeks of pacing, respectively. ANP rose more progressively: 35+/-7 pg/mL at baseline, and 72+/-17, 95+/-10, and 106+/-23 pg/mL after 1, 3, and 12 weeks, respectively. ANP levels correlated with atrial pressure and inducibility of AF. There was no relation between these parameters and AT II levels. CONCLUSION: AT II and ANP increased significantly in this animal model of AF. Elevation of AT II occurs early and seems to be dependent on rapid atrial rate rather than the presence of AF. ANP increased more progressively. It paralleled the inducibility of AF and atrial stretch. Both neurohumoral pathways may form a potential therapeutic target for treatment of patients with AF.

Tilt training: a treatment for malignant and recurrent neurocardiogenic syncope.

The treatment of neurocardiogenic syncope is insufficient in many cases. We hypothesized that the repeated exposure of the cardiovascular system to orthostatic stress could have a therapeutic effect on the regulation of cardiovascular reflex mechanisms. We have started a program of tilt training for heavily symptomatic patients. After hospital admission, patients were tilted daily (60-degree inclination), until syncope, or until a maximum of 45-90 minutes. The patients were instructed to continue a program of daily tilt training at home: two 30-minute sessions of upright standing against a vertical wall. No medication was prescribed. A total of 260 tilt table sessions were performed in 42 patients. The first tilt test was positive after 21 +/- 13 minutes. The syncope was cardioinhibitory in 14 cases, vasodepressor in 19, mixed in 9. At the time of hospital discharge, 41 patients could support 45 minutes of head-up tilting. After a mean follow-up time of 15.1 (SD 7.8) months, 36 patients remained completely free of syncope. Syncope still occurred in one patient and presyncope in four patients. One patient died from an extensive myocardial infarction. The abnormal autonomic reflex activity of neurocardiogenic syncope can be remedied by a program of continued tilt training without the administration of drugs. This new treatment has proven to be effective for the vasodepressor and the cardioinhibitory type of syncope.

Right atrial angiographic evaluation of the posterior isthmus: relevance for ablation of typical atrial flutter.

BACKGROUND: Gaining anatomic information about the posterior isthmus is not generally part of flutter ablation procedures. We postulated that right atrial (RA) angiography could rationalize the ablation approach by revealing the conformation of the isthmus. METHODS AND RESULTS: In 100 consecutive patients, biplane RA angiography was performed before ablation to guide catheter contact with the isthmus along its length. Angiography showed a wide variation in the width of the isthmus (17 to 54 mm; 31.3+/-7.9), its angle with the inferior vena cava in the right anterior oblique projection (68 degrees to 114 degrees; 90.3+/-9.0 degrees ), and its lateral position relative to the inferior vena cava in the left anterior oblique projection. A deep sub-Eustachian recess was revealed in 47%, with a mean depth of 4.3+/-2.1 mm (1.5 to 9.4). A Eustachian valve was visualized in 24%. Ablation resulted in bidirectional conduction block (which could be transient) in all, with a median of 2 dragging radiofrequency (RF) applications (2.3+/-2.5 RF applications; 57 degrees C, < or =99 seconds each). Permanent block was achieved in 99%, with a median of 3 RF applications (3.4+/-3.0). The presence of a Eustachian valve or concave isthmus was associated with statistically more RF applications; the same trend was seen for patients with deep pouches. The number of RF applications decreased statistically throughout the study, indicating a learning curve. No patient had a recurrence after a follow-up of 13+/-11 months. CONCLUSIONS: Right atrial angiography reveals a highly variable isthmus anatomy, often showing particular configurations that can make ablation more laborious. Rational adaptation of the ablation approach to these anatomic findings may contribute to successful ablation.

The value of dipyridamole thallium scintigraphy and dobutamine stress echocardiography as predictors of cardiac complications following reconstruction of the abdominal aorta.

BACKGROUND: The aim of this study was to evaluate the ability of dipyridamole thallium scintigraphy and dobutamine stress echocardiography to predict cardiac complications following elective reconstruction of the abdominal aorta in patients with a stable preoperative cardiac condition and to compare this with information obtained from the medical history, ECG and resting echocardiography alone. METHODS: This evaluation was performed from January 1993 until December 1995 as part of a prospective, randomised study in 200 patients, with a mean age of 65 (5% women). Dipyridamole thallium scintigraphy was performed on 195 patients and dobutamine stress echocardiography was added to the protocol in the last 83 patients. Cardiac complications were defined before the start of the study. RESULTS: In the postoperative period 62 cardiac complications occurred (31%). In patients clinically suspected of having coronary artery disease the incidence of complications was 40% (51/126), compared to 15% (11/74) when no coronary pathology was suspected (p<0.001). When reversible defects were present on dipyridamole thallium scintigraphy the incidence of complications was 36% (20/55), compared to 29% (41/140) when no reversible defects had been found (NS). Dobutamine stress echocardiography was impossible or contraindicated in 21 patients. In the remaining patients the incidence of complications was 71% (5/7) when new regional wall motion abnormalities were found, compared to 16% (9/55) when such abnormalities had not been detected (p<0.005). CONCLUSIONS: These data suggest that cardiac complications following reconstruction of the abdominal aorta in patients with a stable cardiac condition are best predicted by dobutamine stress echocardiography. Dipyridamole thallium scintigraphy, however, does not seem to be useful in this respect.

The analysis of heart rate variability in unrestrained rats. Validation of method and results.

An experimental setting and software were developed to evaluate cardiac autonomic function in unrestrained rats. Subcutaneously implanted ECG electrodes and an indwelling venous catheter were tunneled to a tail cuff in five rats. The ECG was A/D converted at 1000 Hz. After peak detection, a time series of RR intervals was obtained. Programs for the analysis of heart rate variability (HRV) were implemented in LabVIEW. Statistical properties were determined in the time domain. After cubic spline function curve fitting, resampling at 0.1 s and test for stationarity, power spectral analysis was performed on sampled records of 30 min duration after applying a sliding Hanning window (Welch method: 256 points (duration 25.6 s), 50% overlap and 0.039 Hz resolution). Algorithms were tested with simulated signals consisting of isolated frequency components, which were retrieved at their exact locations. Physiological validation of the system was performed by, beta-adrenergic and cholinergic blockade and by forced breathing at a fixed rate. Measurements were performed on five unrestrained rats under basal conditions. Mean RR was 174.2 +/- 3.6 ms; S.D., 13.3 +/- 4.6 ms; rMSSD, 5.2 + /- 1.2 ms; pNN10, 3.5 +/- 1.9% and pNN5, 18.7 +/- 6.4%. Low (0.19-0.74 Hz) and high frequency (0.78-2.5 Hz) power were determined (and also percent of low to total and high to total): 18.42 +/- 10.74 ms2 (22.9 +/- 6.5%) and 15.66 +/- 5.56 ms2 (19.9 +/- 2.7%), and the ratio low/high: 1.16 +/- 0.39. In conclusion, HRV analysis programs were developed and thoroughly tested through simulations and in vivo, under basal conditions and after pharmacological blockades. Using this software, HRV data from unrestrained rats were obtained.