bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acute Left Ventricular Dyssynchrony Improvement Predicts Long‐Term Benefit from Cardiac Resynchronization Therapy
Authors: CAPASSO FABIO , GIUNTA ANNA , DE SIMONE ANTONIO , TURCO PIETRO , LA ROCCA VINCENZO , GRIMALDI M. GABRIELLA , IULIANO ASSUNTA , STABILE GIUSEPPE 
Published: January 2007

Study Objective: To evaluate the relationship between acute response to cardiac resynchronization therapy (CRT) and long‐term clinical outcome in patients with drug refractory heart failure.
Methods and Results: In 28 patients undergoing CRT implant, left ventricular (LV) dyssynchrony was evaluated by tissue Doppler imaging (TDI)‐derived longitudinal strain by mean of septum‐lateral basal asynchrony index (S‐Li) and basal delayed longitudinal contraction (DLC). TDI measurements were made before, and 30 minutes and 1 year after implant. Baseline and 1‐year follow‐up New York Heart Association (NYHA) functional class, 6‐minute walking test (6‐MWT) distance, and quality of life (QoL) score were measured. Responders (n=22) were defined by a ≥ 1 decrease in NYHA functional class and 6‐MWT ≥25% at 1 year. At baseline, no differences were observed between responders and nonresponders in clinical and echocardiographic measurements. LV dyssynchrony acutely recovered only in responders 30 minutes after implantation, with a significant reduction in S‐Li and DLC. Moreover, the percent decreases in S‐Li and DLC were highly correlated with those observed in NYHA class (r=0.70, and r=0.81, respectively, P < 0.001), 6‐MWT (r=0.59, and r=0.57, respectively, P < 0.001 and P < 0.01), and QoL score (r=0.71, and r=0.83, respectively, p < 0.001) at 1‐year follow‐up.
Conclusions: Acute recovery of LV intraventricular dyssynchrony is a major discriminator between responders and nonresponders to CRT, which strongly correlates with a favorable long‐term clinical outcome.
AAIsafeR Limits Ventricular Pacing in Unselected Patients
Authors: PIOGER GUY , LENY GÉRARD , NITZSCHÉ RÉMI , RIPART ALAIN 
Published: January 2007

Introduction: Dedicated pacing modes, such as AAIsafeR, prevent ventricular (V) pacing in selected patients. We report our experience in consecutive unselected patients.
Methods: All data collected in recipients of Symphony DR 2550 pacemakers (ELA Medical, Montrouge, France) were retrospectively analyzed. At each visit, the percentage of V and atrial (A) pacing and the number of endless‐loop tachycardia (ELT) episodes detected by the device were retrieved. Data were pooled according to pacing mode and compared with non‐paired Student's t‐test. Between April 2004 and July 2005, our center recruited 147 patients (mean age=80 ± 9 years, 54% men) treated for AV block (n=58), sinus node dysfunction (n=48) or other indications (n=41). Mean age at implant was 80 ± 9 years, and 54% were men. AAIsafeR(R) was programmed in 96 patients, DDD(R) in 43, DDI in 7, and DDD/AMC in 1 patient. In DDD mode, the mean resting AV delay was set at 150 ± 17 ms. Patients were seen 1 month after implantation of the pacing system to verify its proper function, and every 6 months thereafter. At each follow‐up, the percentage of ventricular and atrial pacing, and the number of ELT detected by the device, were recorded.
Results: The mean follow‐up was 7 ± 6 months (range 1–21). No device was reprogrammed from AAIsafeR(R) to DDDI(R) because of permanent AF. Only 6 devices (6.25%) were automatically reprogrammed from AAIsafeR(R) to DDD(R) during follow‐up due to permanent AV block. An empirical choice of AAIsafeR pacing mode at the time of implantation was effective in 94% of patients, allowing a significant decrease in the percentage of V pacing. AAIsafeR versions 1 or 2 significantly decreased the percentage of V pacing (9 ± 21%) compared with DDD (95 ± 14%), DDD/AMC (31 ± 34%), and DDI (87 ± 20%) pacing (P < 0.00001). The mean percentage of V pacing was 12 ± 24% (median 0%, range 0–94) in AAIsafeR1 versus 4 ± 12% (median 0%, range 0–52) in AAIsafeR2 (P=0.055). In 16 devices upgraded from AAIsafeR version 1 to version 2, with follow‐up analyzable in both modes, the mean percentage of V pacing decreased from 6.4 ± 15.1% to 2.6 ± 9.7% (ns). No adverse effect related to the AAIsafeR modes was observed. No patient reported palpitation, dyspnea, or lightheadedness attributable to overdrive pacing by the AF prevention algorithms, and there was no rehospitalization, need for cardioversion, device‐related complication, or death.
Conclusions: In unselected pacemaker recipients, AAIsafeR reliably prevented V pacing compared with other pacing modes. No adverse effects were reported by any patient. Furthermore, maintaining spontaneous AV conduction protected the patients against ELT episodes.
Dynamic and Dual‐Site Atrial Pacing in the Prevention of Atrial Fibrillation: The STimolazione Atrial DInamica Multisito (STADIM) Study
Authors: DE SIMONE ANTONIO , SENATORE GAETANO , DONNICI GIOVANNI , TURCO PIETRO , ROMANO ENRICO , GAZZOLA CARLO , STABILE G. 
Published: January 2007

Objectives: The impact of new algorithms to consistently pace the atrium on the prevention of atrial fibrillation (AF) remains unclear. Our randomized, crossover study compared the efficacy of single‐ and dual‐site atrial pacing, with versus without dynamic atrial overdrive pacing in preventing AF.
Methods: We studied 72 patients (mean age=69.6 ± 6.5 years, 34 men) with sick sinus syndrome (SSS) and paroxysmal or persistent AF, who received dual‐chamber pacemakers (PM) equipped with an AF prevention algorithm and two atrial leads placed in the right atrial appendage (RAA), by passive fixation, and in the coronary sinus ostium (CS), by active fixation, respectively. At implant, the patients were randomly assigned to unipolar CS versus RAA pacing. The PM was programmed in DDDR mode 1 month after implant. Each patient underwent four study phases of equal duration: (1) unipolar, single site (CS or RAA) pacing with the AF algorithm ON (atrial lower rate=50 ppm); (2) unipolar, single site pacing with the AF algorithm OFF (atrial lower rate=70 bpm); (3) bipolar, dual‐site pacing with AF algorithm ON; (4) bipolar, dual‐site pacing with the AF algorithm OFF.
Results: Among 40 patients (56%), who completed the follow‐up (15 ± 4 months) no difference was observed in the mean number of automatic mode switch (AMS) corrected for the duration of follow‐up, in unipolar (5.6 ± 22.8 vs 2.6 ± 5.5) or bipolar mode (3.3 ± 12.7 vs 2.1 ± 4.9) with, respectively, the algorithm OFF or ON. With the AF prevention algorithm ON, the percentage of atrial pacing increased significantly from 78.7 ± 22.1% to 92.4 ± 4.9% (P < 0.001), while the average ventricular heart rate was significantly lower with the algorithm ON (62.4 ± 17.5 vs 79.9 ± 3 bpm (P < 0.001).
Conclusions: The AF prevention algorithm increased the percentage of atrial pacing significantly, regardless of the atrial pulse configuration and pacing site, while maintaining a slower ventricular heart rate. It had no impact on the number of AMS in the unipolar and bipolar modes in patients with SSS.
Thresholds and Complications with Right Ventricular Septal Pacing Compared to Apical Pacing
Authors: BURRI HARAN , SUNTHORN HENRI , DORSAZ PIERRE‐ANDRÉ , VIERA ISABELLE , SHAH DIPEN 
Published: January 2007

Background: Right ventricular septal pacing has been proposed as an alternative to apical pacing. However, data concerning thresholds and requirement for lead repositioning with this technique are scant.
Methods: We reviewed data at implantation and follow‐up of 362 consecutive recipients of the same model of active fixation lead (Medtronic 5076‐58, Minneapolis, MN, USA) to avoid differences due to lead characteristics. Patients were divided into two groups according to whether the lead was positioned on the interventricular septum (n = 157) or at the right ventricular apex (n = 205). Thresholds, lead impedance, and requirement for lead repositioning were compared between groups at implantation and follow‐up.
Results: There were no differences between the septal and apical groups in sensing and pacing thresholds or lead impedance, either at implantation or during a 24‐month follow‐up. In the septal group, the lead had to be repositioned in four patients (2.5%) due to lead dislodgement in two patients, acute threshold rise in one patient, and pericardial effusion in another patient (the lead had unintentionally been positioned on the anterior free wall in these last two patients). In the apical group, the lead had to be repositioned in eight patients (3.9%, P = 0.56) due to lead dislodgement in three patients and acute threshold rise in five patients.
Conclusions: Acute and chronic thresholds associated with septal pacing are similar to those observed with apical pacing, and risk of lead dislodgement is low. However, multiple radioscopic views must be used to avoid inadvertent positioning of the lead on the anterior free wall.
Placement of a Pacing Lead at the Inferior Portion of the Interatrial Septum Without Special Tools
Authors: ACOSTA HELBERT , POTHULA VIJAYASIMHA R. , RODRIGUEZ MARIO , RAMADAS SUMATI , CASTELLANOS AGUSTIN 
Published: January 2007

Introduction: Previous studies have suggested that, among septal sites, the inferior portion of the interatrial septum (IAS) is the most likely to prevent atrial fibrillation, though inserting an active fixation lead at this site can be tedious and time consuming. We describe a relatively straightforward technique to insert a lead at this site without special tools.
Method: We studied 117 consecutive patients (mean age=76 ± 8 years, 69% men) with ACC/AHA class I and II pacing indications and histories of paroxysmal or permanent atrial fibrillation, undergoing implantation of a dual chamber pacing system. A technique using the “preshaped” stylet and fluoroscopic guidance is described.
Results: The insertion was successful in 111 patients (95%). Acute dislodgement occurred in six patients (5%). The intrinsic P‐wave duration was 117 ± 22 ms, and the paced P‐wave duration was 90 ± 20 ms (23% shortening, P < 0.001). The mean time required to insert the atrial lead was 12 ± 8 minutes. No complications occurred.
Conclusions: Insertion of an active fixation lead at the inferior portion of the interatrial septum was safe and highly successful in the majority of patients with this technique.
Atrioventricular Nodal Reentrant Tachycardia in the Elderly: Efficacy and Safety of Radiofrequency Catheter Ablation
Authors: MEILTZ ALEXANDRE , ZIMMERMANN MARC 
Published: January 2007

Background: Radiofrequency (RF) catheter ablation is considered the treatment of choice for patients with atrioventricular nodal reentrant tachycardia (AVNRT). This study examined the efficacy and safety of RF ablation in patients with AVNRT ≥65 years of age.
Methods: We retrospectively analyzed data collected in 350 consecutive patients who underwent AVNRT RF ablation between 1995 and 2005. They were divided according to whether they were <65 years (Group 1, n = 280; mean age = 46 ± 13 years, 69% women) or ≥65 years (Group 2, n = 70; mean age = 72 ± 6 years, 59% women) of age.
Results: Patients in Group 2 more often had structural heart disease (12/70 vs 17/280, P = 0.002) than in Group 1, though there was no difference in the prevalence of syncope (6/70 vs 18/280, P = 0.52) or atrial fibrillation (1/70 vs 6/280, P = 0.70) between the 2 groups. Before RF ablation, patients in Group 2 had a longer mean A‐H intervals (90 ± 31 ms vs 77 ± 19 ms, P < 0.0001), H‐V intervals (44 ± 6 ms vs 41 ± 5 ms, P < 0.0001), fast pathway refractory period (358 ± 14 ms, vs 335 ± 68 ms, P = 0.01), and tachycardia cycle length (394 ± 71 ms vs. 335 ± 59 ms, P < 0.0001). A >140 ms A‐H interval was present in 3/70 patients in Group 2 versus 0/280 in Group 1 (P < 0.001). No difference was observed between the 2 groups in primary RF ablation success rate (70/70 vs 277/280, P = 0.38), overall procedure duration (75 ± 35 minute vs 78 ± 43 minute, P = 0.61), duration of fluoroscopic exposure (14 ± 12 minute vs 13 ± 12 minute, P = 0.63), or number of RF pulses (median 5 vs 4, P = 0.051). Two patients in Group 1 (0.57%) developed 3rd degree AV block requiring permanent pacing. Recurrences of AVNRT were limited to Group 1 (16/280 vs 0/70, P = 0.001).
Conclusions: RF ablation of AVNRT was highly effective and safe in patients ≥65 years of age despite a higher prevalence of structural heart disease and longer A‐H intervals at baseline. RF ablation might be considered as first‐line therapy for the elderly with AVNRT.
Significance of Late Recurrence of Atrial Fibrillation during Long‐Term Follow‐Up after Pulmonary Vein Isolation
Authors: SOLHEIM EIVIND , HOFF PER IVAR , OFF MORTEN KRISTIAN , OHM OLE‐JØRGEN , CHEN JIAN 
Published: January 2007

Background and Study Objective: Patients with paroxysmal or persistent atrial fibrillation (AF) can be treated by pulmonary vein (PV) isolation. Although the recurrence rate after the procedure is relatively high, the long‐term outcomes after initially recurrence‐free procedures remains unclear. We examined the rates of recurrence of AF after PV isolation.
Methods: Our study included 278 consecutive patients with drug‐refractory AF (mean age = 53 ± 11 years, 228 men). PV isolation was based on the disappearance of PV potentials recorded from a circumferential catheter after segmental ostium ablation. Cavo‐tricuspid isthmus lines and additional atrial lines were performed in 124 and 28 patients, respectively. Patients were monitored for a mean of 26 ± 11 months (range 12–56). Recurrence was defined as ≥1 episodes of symptomatic or asymptomatic AF >1 month after the procedure.
Results: A total of 120 (34) patients had ≥1 recurrence of AF >1 month after the procedure, of whom 14 (4) had a first recurrence >6 months after the procedure. There was a significantly higher recurrence rate among patients with persistent AF.
Conclusions: A relatively high AF recurrence rate was observed after PV isolation. AF may recur late after the ablation procedure, though the majority of recurrences occurred within 6 months after the first procedure. There were no differences in incidence or time of occurrence of late recurrences between patients with paroxysmal versus persistent AF.
Antiarrhythmic Drug Therapy after Radiofrequency Catheter Ablation in Patients with Atrial Fibrillation
Authors: TURCO PIETRO , DE SIMONE ANTONIO , LA ROCCA VINCENZO , IULIANO ASSUNTA , CAPUANO VINCENZO , ASTARITA COSTANTINO , DI NAPOLI TOMMASO , MESSINA VINCENZO , BALDI SILVANO , STABILE GIUSEPPE 
Published: January 2007

Objectives: The use of antiarrhythmic drugs after ablation is a controversial issue when evaluating the efficacy of atrial fibrillation (AF) ablation. This study compares in a prospective and randomized fashion the impact of an antiarrhythmic drug in preventing AF recurrence after AF ablation.
Methods: From February 2004 to May 2005, 107 consecutive patients (mean age 57 ± 10 years, 69 men), with paroxysmal (60%) or persistent (40%) drug refractory AF, were randomly assigned to ablation alone (Group A, 53 patients) or combined with the best antiarrhythmic therapy, preferably amiodarone (Group B, 54 patients). All patients underwent cavo‐tricuspid and left inferior pulmonary vein (PV)‐mitral isthmus ablation plus circumferential PV ablation, using a guided electro‐anatomical approach. Standard electrocardiograms (ECG), and ambulatory and transtelephonic ECG monitoring were used to assess AF recurrences. Recurrences during the first month after ablation were excluded from this analysis.
Results: At 12 months of follow‐up, no significant difference was observed in the rates of AF recurrences between Group A (18/53 patients, 34%) and Group B (16/54 patients, 30%). The percentage of patients with ≥1 asymptomatic AF episode was higher in Group B than in Group A (10/16 patients, 63%, vs 5/18 patients, 28%, P = 0.04).
Conclusions: Continuing antiarrhythmic drug therapy in patients who undergo catheter ablation for AF did not lower the rate of AF recurrences. Antiarrhythmic drugs increased the proportion of patients with asymptomatic AF episodes.
Usefulness of Transesophageal Echocardiography in the Isolation of Pulmonary Veins in the Treatment of Atrial Fibrillation
Authors: CHAMPAGNE JEAN , ECHAHIDI NAJMEDDINE , PHILIPPON FRANÇOIS , ST‐PIERRE ANDRÉ , MOLIN FRANCK , BLIER LOUIS , GILBERT MARCEL , VILLENEUVE JACQUES , MOHTY DANIA , O'HARA GILLES 
Published: January 2007

Background: New imaging strategies for atrial fibrillation (AF) ablation should enhance the safety of this technique. The role of transesophageal echocardiography (TEE) in this setting has not been prospectively evaluated.
Methods: Under general anesthesia, 85 patients underwent TEE‐guided AF ablation. A hybrid technique was performed with circular pulmonary veins (PV) lesions and antrum and ostial electrical isolation guided by TEE. TEE excluded left atrial (LA) thrombus, guided transseptal puncture and catheter positioning, and helped to identify PV ostia and their velocities. The TEE probe localized the esophagus, its temperature (T°) and micro bubbles formation.
Results: Overall, one patient had a LA clot. The esophagus was located close to left PV in 38%, the right PV in 28%, midline in 17% and with an oblique course in 17% of patients. Right and left superior PV velocities were detected in 100%, left inferior PV in 88% and right inferior PV in 82% of patients. Microbubbles were detected in 9 patients (11%). Elevation of TEE T° occurred in 14 patients (16%) and was regularly observed when lesions were applied over the TEE probe shadow, in close proximity to the posterior wall. Two major complications (1 tamponade, 1 PV laceration) occurred and were detected early by TEE.
Conclusions: TEE offers advantages compared to a map‐guided only approach. It is a reliable tool to assess esophagus T° and localization, guide transseptal puncture, delineate the PV ostia, and monitor complications.
Incidence and Characteristics of Appropriate and Inappropriate Therapies in Recipients of ICD Implanted for Primary Prevention of Sudden Cardiac Death
Authors: KREUZ JENS , BALTA OSMAN , LILIEGREN NORA , MELLERT FRITZ , ESMAILZADEH BAHMAN , NICKENIG GEORG , SCHWAB JÖRG OTTO 
Published: January 2007

Background: We evaluated the number of appropriate and inappropriate therapies for ventricular tachyarrhythmias and trigger mechanisms in 55 MADIT II (MII)‐like (group 1) and 86 SCD‐HeFT‐like (group 2) patients.
Methods and Results: We analyzed 399 appropriate episodes in 31 patients with implantable cardioverter defibrillators (ICD) implanted according to the MII trial indications, and 502 appropriate episodes in 47 patients matching the SCD‐HeFT trial criteria (mean follow‐up in both groups = 33 ± 19 months). In group 1, 39 treated episodes were inappropriate (9% of all episodes), while in group 2, 76 episodes were treated inappropriately (15% of all episodes). At least one episode of inappropriate ICD therapy was recorded in 18% of patients in group 1 (n = 10) and in 22% of patients in group 2 (n = 19).
Conclusions: Our study supports the implantation of ICD as primary prevention in patients who are at risk of sudden cardiac death, although the proportion of inappropriate ICD interventions remains high.
Prevention of Inappropriate Shocks in ICD Recipients: A Review of 10,000 Tachycardia Episodes
Authors: ANSELME FRÉDÉRIC , MLETZKO RALPH , BOWES ROBERT , MABO PHILIPPE , SADOUL NICOLAS , SCHOELS WOLFGANG , SEIDL KARLHEINZ , SCHWAB JOERG , ISCOLO NICOLAS , NITZSCHÉ RÉMI 
Published: January 2007

Background: The efficacy of dual‐chamber ICD arrhythmia classification algorithms is crucial to prevent inappropriate shocks. We report our experience from a meta‐analysis of five prospective clinical studies with inclusion phases ranging between 1997 and 2003.
Methods: Dual‐chamber ICD using standard dual‐chamber arrhythmia classification algorithms were implanted in 802 patients (mean age = 64 ± 11 years, 88% men) in 74 medical centers. The ICD indication was secondary prevention in 95% of patients. Supraventricular tachyarrhythmias (SVT) were previously documented in 26% of patients. All spontaneous tachyarrhythmic events documented by the device memories were analyzed by a adjudicating committee. The episodes lasting >12 seconds and/or treated by the ICD were analyzed.
Results: Over a mean follow‐up of 302 ± 113 days, 9,690 events were reported. Mean heart rate at the time of events was 131 ± 45 bpm (100–430). Events were classified as oversensing in 1.4%, sinus tachycardia (ST) in 66%, SVT in 13%, slow (<150 bpm) ventricular tachycardia (VT) in 8.7%, and VT or ventricular fibrillation (VF) in 10.3%. The sensitivity of slow VT detection was 94%, and of VT/VF detection 99.3%. The specificity of sinus rhythm/ST/SVT recognition was 94%, positive predictive value 79.3%, and negative predictive value 99.2%. A total of 1,918 episodes were treated in 330 patients: 1,472 appropriately in 213, and 446 inappropriately in 117 (15% of the overall population) patients. Only 62 episodes were inappropriately treated by shocks in 40 patients, representing 5% of the overall population.
Conclusions: In this conventional ICD population, the overall specificity of standard dual‐chamber arrhythmia detection settings reached 94%. This feature allows efficient detection of fast as well as slow VT events with a very low rate of inappropriate shocks.
Outcomes of Elderly Recipients of Implantable Cardioverter Defibrillators
Authors: GRIMM WOLFRAM , STULA ASTRID , SHARKOVA JULIA , ALTER PETER , MAISCH BERNHARD 
Published: January 2007

Aims of the Study: To examine the patterns of use, complication rates, and survival in elderly recipients of implantable cardioverter defibrillators (ICD).
Methods and Results: We followed 500 consecutive patients included in the Marburg Defibrillator database for 48±39 months. There were 40 patients (8%) ≥75 and 460 (92%) <75 years of age at the time of implant. The 5‐year Kaplan‐Meier estimate for appropriate treatment of VT or VF by ICD was 49% among patients <75‐ versus 57% among patients ≥75‐years‐old (P = 0.17). The 5‐year sudden death rate was similarly low in both groups of patients (2% versus 3%). The 5‐year overall mortality rate was significantly higher in patients ≥75 than in patients <75 years of age (55% versus 21%, P = 0.001), due to a higher mortality from heart failure (HF). All procedure‐related, lead‐related, and pulse generator‐related complications were similar in both patient groups (23% versus 25%).
Conclusions: ICD therapy was equally effective in patients ≥75 and patients <75 years of age in the prevention of sudden cardiac death. While the complication rates were similar in both age groups, the long‐term mortality was considerably higher in elderly patients, due to a higher mortality from HF. The current ICD therapy guidelines appear applicable to elderly patients who are otherwise medically stable and without advanced HF.