Acute performance evaluation of a new ventricular automatic capture algorithm

Aims This study evaluated the acute clinical performance of a new ventricular automatic capture algorithm developed to work with all lead types and pacing vectors. Methods and results During regular pacemaker implant or replacement, AutoThreshold and manual threshold tests were performed in ventricular unipolar (UP) and bipolar (BP, if applicable) pacing using a customized external prototype INSIGNIA™ pacemaker. The success rate and accuracy of two different modes (commanded and ambulatory) of the automatic capture algorithm were used to evaluate the performance. Loss-of-capture events (two consecutive non-captured beats without backup pacing) were used to assess safety. Data of 53 patients…

Low-energy epicardial pacing in children: the benefit of autocapture.

Abstract Background . Permanent cardiac pacing in children results commonly in augmented energy consumption because of the high pacing rates and the ample stimulation safety margin applied in children. Cardiovascular anatomy and limited venous access sometimes preclude the otherwise preferred endocardial approach. In this multicenter patient series, we studied the feasibility, safety, and energy saving obtained by a combination of steroid-eluting epicardial leads with autocapture devices capable of ongoing adjustment of the stimulation output to the prevailing threshold. Methods . Autocapture devices (Pacesetter Microny SR+ and Regency SR+; Pacesetter, Solna, Sweden) and steroid-eluting epi…

Development of a coronary aneurysm 6 months after stent implantation assessed by intracoronary ultrasound.

Erste Erfahrungen mit einem neuen Therapiekonzept für die Schrittmacherbehandlung von Säuglingen und Kleinkindern

Fragestellung: Fur Sauglinge und Fruhgeborene ist eine geringe Grose des Schrittmacheraggregats besonders wichtig. Unsere bisherigen Erfahrungen mit dem kleinsten, z.Z. verfugbaren Pulsgenerator bei Kindern wurden analysiert und hier vorgestellt. Methode: Bei 2 Fruhgeborenen mit symptomatischem kompletten AV-Block und einem 8jahrigen Patienten mit kongenitalem AV-Block bei komplexen Vitium und Palliation mittels totaler kavopulmonaler Anastomose wurde der kleinste z.Z. verfugbare Pulsgenerator erstmals mit bipolaren, epikardialen steroideluierenden Elektroden implantiert. Dieser Schrittmacher arbeitet durch den Autocapture-Algorithmus besonders energiesparend, so das trotz geringerer Batter…

Paroxysmal atrial fibrillation and high degree AV block: use of single-lead VDDR pacing with mode switching.

Dual chamber rate responsive pacing incorporating a mode switching option is increasingly used in patients with chronic paroxysmal atrial fibrillation and high degree AV block. Single-lead VDDR pacemakers have rarely used for this indication. The purpose of this study was to determine their reliability of atrial sensing during atrial fibrillation, the percentage of atrial synchronous ventricular pacing, and the behavior of the sinus rate outside the phases of atrial fibrillation. We studied ten patients with a single-lead VDDR pacemaker implanted for this indication. Follow-up visits were performed at predischarge and after 1, 3, 6, 12, 18, and 24 months. During the mean follow-up period of…

A simple method for preoperative assessment of the best fitting electrode length in single lead VDD pacing.

For single lead VDD pacing, electrodes with various distances between the lead tip and the floating atrial dipole (AV distance) are available. Using different AV distances allows positioning of the atrial dipole in the mid- to high right atrium, regardless of the size of the right heart. In this position, reliable atrial sensing and rejection of ventricular far-field potentials can be expected. A simple test for the preoperative assessment of the best fitting AV distance in the individual patient was tested. We studied 24 consecutive patients prior to implantation of a VDD pacemaker. With the patient in supine position, a test electrode with an AV distance of 13 cm was taped onto the thorax…

Is atrial sensing of ventricular far-field signals important in single-lead VDD pacing?

UNLABELLED In single-lead VDD pacing the atrial sensitivity frequently is programmed to sensitive values. Atrial sensing of ventricular far-field signals should be reduced by differential atrial sensing. The aim of the study was to evaluate the effectiveness of this approach. METHODS The study included 10 patients with a single-lead VDD pacemaker (Thera 8948, Lead 5032). The atrial sensitivity was set to its most sensitive value of 0.18 mV and the telemetered intraatrial EGM was continuously recorded. After atrial tracked ventricular pacing, VVI pacing was performed with pacing rates from 100 to 160 beats/min in steps of 10 beats/min and up to 165 beats/min. The peak-to-peak amplitudes of P…

Anomalous Origins of the Left Main Coronary Artery From the Noncoronary Sinus and of the Right Coronary Artery From the Left Sinus of Valsalva

A 70-year-old man was referred for recent-onset angina. The ECG showed a right-axis deviation and signs of an old anterior infarction with loss of R waves in leads V1 through V5. Chest radiograph demonstrated a markedly enlarged heart, which was shifted to the left side with discrete signs of pulmonary congestion. Transthoracic echocardiography, which was limited by poor imaging quality, revealed a normal left ventricular cavity with reduced ejection fraction (40%) due to hypokinesia of the anterior wall. Coronary angiography showed the dominant RCA to originate from the left sinus of Valsalva. It coursed between the aorta and the pulmonary artery to the right (Figs …

Aktuelle Ergebnisse der DAVE-Studie, DDD- und VDD-Evaluation: Eine prospektive randomisierte Studie zum Vergleich der DDD- und VDD-Stimulation bei AV-Block

Single-lead VDD-Systeme: Eine Alternative zu DDD-Systemen bei Patienten mit AV-Block

VDD- und DDD-Systeme in der Therapie des isolierten AV-Blocks werden anhand der Kriterien Implantation und Komplikationen, Sicherheit der atrialen Wahrnehmung, Erhalt der AV-synchronen Stimulation, Notwendigkeit einer atrialen Stimulation, Inzidenz atrialer Rhythmusstorungen und Schrittmachernachsorge gegenubergestellt.

Cardiac output in single-lead VDD pacing versus rate-matched VVIR pacing.

The importance of atrioventricular synchronous pacing compared with single-chamber rate-responsive pacing is still under discussion, especially for low-intensity workload representing daily life activities. We evaluated hemodynamics in single-lead VDD pacing versus VVIR pacing in 11 patients (8 men and 3 women, aged 58.6 +/- 13.8 years) with normal left ventricular function and a previously implanted single-lead VDDR pacemaker. A low-intensity steady-state treadmill test at 1 to 2.5 mph with a gradient of 2% to 4% was performed. Cardiac output was determined using a standard carbon dioxide rebreathing technique. Initially, the VDD mode was programmed, and after 5 minutes of exercise, cardia…

Die Spätpotentialanalyse in der Diagnostik nach akutem Myokardinfarkt:¶Risikomarker für den Arrhythmie-gefährdeten und klinisch symptomatischen Patienten (Late potentials in postinfarction patients: arrhythmogenic risk and clinical characteristics)

Ziel der prospektiven Studie ist die Korrelation ventrikularer Spatpotentiale mit klinischen Parametern bei Patienten nach akutem Myokardinfarkt. Es wurde die prognostische Wertigkeit dieser Methode hinsichtlich der Risikostratifizierung bezuglich des plotzlichen Herztodes in der spaten Postinfarktphase im Vergleich mit herkommlichen diagnostischen Moglichkeiten uberpruft. Zudem wurde untersucht, welche klinischen Symptome die potentiell gefahrdeten Patienten charakterisieren.

How Can We Identify the Best Implantation Site for an ECG Event Recorder?

ZELLERHOFF, C., et al.: How Can We Identify the Best Implantation Site for an ECG Event Recorder? The aim of this study was to show how to find the preferable implantation site for an ECG event recorder (ECG-ER). We compared the quality of bipolar ECG recordings (4-cm electrode distance, vertical position) in 65 patients at the following sites: left and right subclavicular, left and right anterior axillary line (4th-5th interspace), left and right of the sternum (4th-5th interspace), heart apex, and subxyphoidal. The results were compared to the standard ECG lead II. In 30 patients, an additional comparison between vertical and horizontal ECG registrations was done using the same sites. ECG…

Ectasia and Aneurysm of the Right Coronary Artery Resulting From a Shunt to the Coronary Sinus

A 65-year-old woman presented with a systolic-diastolic murmur. Further MRI investigations as well as angiography revealed an arteriovenous shunt to the coronary sinus via an enlarged right coronary artery (Figure 1A⇓ and 1B⇓). The distal part of this coronary artery was transformed to a large coronary aneurysm of such extent that the left atrium was compressed …

VDD(R)-Stimulation mit Mode-Switch bei paroxysmalem Vorhofflimmern und AV-Block: Verlauf über 2 Jahre

Comparison of prognostic usefulness (three years) of computed tomographic angiography versus 64-slice computed tomographic calcium scanner in subjects without significant coronary artery disease.

Coronary computerized tomographic angiography (CTA) has been used as a noninvasive method for ruling out high-grade stenoses. Even in the absence of such stenoses, analysis of coronary atherosclerosis may provide for important prognostic information, and this may be superior to exclusive coronary artery calcium scoring. We tested this hypothesis in patients undergoing CTA for clinical indications who had no stenoses requiring revascularization. From December 2004 to December 2006, 706 consecutive patients who underwent CTA but had no high-grade stenoses were included (58% men, mean age 59 ± 11 years). CTA and coronary artery calcium scoring (Agatston method) were performed using a 64-slice …

Comparison of ReoPro((R)) (abciximab) versus intracoronary thrombolysis for early coronary stent thrombosis.

AIMS: This study evaluated the treatment of early coronary stent thrombosis with intracoronary urokinase or the platelet glycoprotein IIb/IIIa receptor inhibitor ReoPro (abciximab). METHODS AND RESULTS: Seventy-four patients (126 stents) were treated immediately after identification of early (0-30 days) coronary stent thrombosis. Twenty-nine patients were treated with intracoronary urokinase (UK) (UK alone in 19; UK and additional balloon angioplasty in 10) and another 45 patients were given ReoPro((R)) (abciximab) (0.25 mg/kg as a bolus alone in 26, abciximab with additional balloon angioplasty in 19) within 30 days of stent implantation. TIMI grade 3 flow was obtained in 23 patients (79%)…

Implantation Strategy of the Atrial Dipole Impacts Atrial Sensing Performance of Single Lead VDD Pacemakers

WIEGAND, U.K.H., et al.: Implantation Strategy of the Atrial Dipole Impacts Atrial Sensing Perfor-mance of Single Lead VDD Pacemakers. Intermittent atrial undersensing is observed in a considerable percentage of patients with single lead VDD pacemakers. Analyzing the 2-year data of the Saphir Multicenter Follow-Up Study, the authors investigated predictors for the occurrence of undersensing. The study included 194 patients with high degree AV block who received a VDD pacemaker system with an identical sensing amplifier. Placement strategy of the atrial dipole was left to the discretion of the implanting physician. At the final position, atrial potential amplitudes were measured during deep …

Clinical application of a new rheolytic thrombectomy catheter system for massive pulmonary embolism

Intravascular ultrasound detected classification of coronary lesions as a predictor of dissections after balloon angioplasty.

Dissection after balloon angioplasty of coronary arteries may give rise to an unfavourable early outcome. Compared with coronary angiography, intravascular ultrasound (IVUS) allows more detailed characterisation of dissections. We investigated the incidence and type of dissections after balloon angioplasty in calcified coronary lesions. IVUS was performed in 43 patients with 48 lesions before and after percutaneous balloon angioplasty. Significant calcification was defined as an arc of more than 90 degrees with typical acoustic shadowing. Dissections were classified as type A when the media was not involved by the dissection and as type B when media involvement had occurred. In the group wi…

Self-referral to chest pain units: results of the German CPU-registry

Chest pain units (CPUs) are increasingly established in emergency cardiology services. With improved visibility of CPUs in the population, patients may refer themselves directly to these units, obviating emergency medical services (EMS). Little is known about characteristics and outcomes of self-referred patients, as compared with those referred by EMS. Therefore, we described self-referral patients enrolled in the CPU-registry of the German Cardiac Society and compared them with those referred by EMS.From 2008 until 2010, the prospective CPU-registry enrolled 11,581 consecutive patients. Of those 3789 (32.7%) were self-referrals (SRs), while 7792 (67.3%) were referred by EMS. SR-patients w…

Comparison of antiplatelet effects of aspirin, ticlopidine, or their combination after stent implantation.

Background —This study was performed to analyze the influence of either aspirin, ticlopidine, or their combination on platelet activation and aggregation parameters after stent implantation. Methods and Results —Sixty-one patients with successful implantation of a single Palmaz-Schatz stent in a native coronary artery were randomly assigned to either group A (aspirin 300 mg/d+ticlopidine 2×250 mg/d), group B (ticlopidine 2×250 mg/d), or group C (aspirin 300 mg/d). Platelet activation was evaluated on days 1, 7, and 14 by flow cytometry measurement of expression of CD62p (p-selectin) and the binding of fibrinogen to the platelet surface glycoprotein IIb/IIIa receptor. Platelet aggregation w…

Device-Therapie nach akutem Koronarsyndrom

AV-Blocke sind beim akuten Koronarsyndroms selten. Nur wenige Patienten benotigen eine Schrittmacherimplantation. Besonders beim Hinterwandinfarkt ist die Prognose gut. Die Haufigkeit anhaltender AV-Blockierungen hat durch die Akut-PTCA abgenommen. Ventrikulare Tachyarrhythmien sind in der Akutphase des Infarktes haufig. Treten sie als anhaltende Kammertachykardien oder Kammerflimmern > 48 Stunden nach Infarkt auf, konnen sie eine Indikation zur sekundarprophylaktischen ICD-Implantation darstellen. Primarprophylaktisch sollte ein Defibrillator implantiert werden, wenn die LV-EF auch > 40 Tage nach Infarkt ≤ 35 % betragt. Ist fruh nach Infarkt eine Aggregatimplantation erforderlich, sollte b…

Schrittmachertherapie bei Frühgeborenen mit AV-Block: Erstmaliger Einsatz von „Autocapture” mit epikardialer Elektrode

Experimentelle Untersuchungen zum Einsatz verschiedener atrialer Dipolkonfigurationen für die Vorhof-Stimulation mit VDD-Elektroden

Fourier-Analyse der P-Welle bei der VDD-Stimulation. Ein intra-individueller Vergleich verschiedener atrialer Dipolkonfigurationen

Der Frequenzinhalt der wahrgenommenen P-Welle wird bei der VDD-Stimulation sowohl von der Dipollokalisation, als auch von der Dipolkonfiguration beeinflust. Eine Vergroserung der Dipoloberflache resultiert in der Detektion tieferer Frequenzen.

Cardiac pacing in premature infants and neonates: steroid eluting leads and automatic output adaptation

Abstract Background . Appropriate generator and lead selection as well as techniques of implantation are most important aspects of cardiac pacing in the extremely young patient. Here we report the clinical results using a new technique with automatic output adaptation based on evoked response in combination with steroid-eluting epicardial leads in small children. Methods . One neonate and 2 premature infants underwent permanent pacemaker implantation because of congenital high-degree atrioventricular block or postoperative complete heart block, respectively. Steroid-eluting epicardial leads and a multiprogrammable pacemaker with automatic output adaptation were used. Results . Intermuscular…

Pacemaker therapy in premature children with high degree AV block.

The smallest pacemaker pulse generator and a steroid-eluting bipolar epicardial lead were implanted in two premature children with symptomatic AV block. Stable capture threshold and high amplitude evoked response electrogram resulted in normal function of the pacemaker Autocapture algorithm, which adjusts output 0.3 V above the measured capture threshold. Autocapture had previously been used only with endocardial leads. Longer-term observation is required.