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programming optimal atrioventricular delay in dual chamber pacing using acceleration: Comparison with a standard echocardiographic procedure

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PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY 2003年第1期26卷 210-213页

作者： Dupuis, JM Kobeissi, A Vitali, L Gaggini, G Merheb, M Rouleau, F Leftheriotis, G Ritter, P Victor, J Univ Hosp Angers Dept Cardiol F-49033 Angers 01 France Sorin Biomed CRM Saluggia Italy InParys Paris France

Optimization of programmed atrioventricular delay in dual chamber pacing is essential to the hemodynamic efficiency of the heart. Automatic AV delay optimization in an implanted pacemaker is highly desirable. Variations of peak endocardial acceleration (PEA) with AV delay at rest correlate well with echocardiography derived observations, particularly with end-diastolic filling and mitral valve closure timings. This suggests the possibility of devising a procedure for the automatic determination of the optimal AV delay. The aim of this study was to compare a proposed algorithm for optimal AV delay determination with an accepted echocardiographic method. Fifteen patients with high degree AV block received BEST-Living pacing systems, Automatic AV delay scans were performed at rest (60-300 ms in 20-ms steps with 60 beats per step) in DDD at 90 ppm, while simultaneously recording cycle-by-cycle PEA values, which were averaged for each AV delay to obtain a PEA versus AV delay curve. Nonlinear regression analysis based on a Boltzmann sigmoid curve was performed, and the optimal AV delay (OAVD) was chosen as the sigmoid inflection point of the regression curve. The OAVD was also evaluated for each patient using the Bitter echocardiographic method. Good sigmoid fit was obtained in 13 of 15 patients. The mean OAVD obtained by the PEA sigmoid algorithm was 146.9 +/- 32.1 ms, and the corresponding result obtained by echocardiography was 156.4 +/- 34.3 ms (range 31.8-39.7 ms). Correlation analysis yielded r = 0.79, P = 0.0012. In conclusion, OAVD estimates obtained by PEA analysis during automatic AV delay scanning are consistent with those obtained by echocardiography. The proposed algorithm can be used for automatic OAVD determination in an implanted pacemaker pulse generator.

关键词： atrioventricular delay peak endocardial acceleration pacemaker programming

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Preventive pacing in patients with paroxysmal atrial fibrillation: programming and follow-up of patients with dual-chamber pacemakers and triggered preventive pacing functions

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Herzschrittmachertherapie und Elektrophysiologie 2002年第1期13卷 20-29页

作者： Schuchert, A. Meinertz, T. Medizinische Klinik Abteilung für Kardiologie Universitätsklinikum Hamburg-Eppendorf 20246 Hamburg Martinistr. 52 Germany

A treatment of patients with paroxysmal atrial fibrillation is the implantation of DDDRP pacemakers for preventive pacing. Atrial pacing with the aim for preventive pacing of atrial fibrillation can be classified as continuous constant pacing with a fixed manually programmed lower atrial pacing rate. The second approach is continuous dynamic overdrive pacing realized by new pacing algorithms, e. g., Pace Conditioning in the Vitatron DDDRP pacemakers. The third approach is discontinuous triggered pacing when specific pacing algorithms are activated by trigger events and temporally pace the atrium. The actual established indications for preventive pacing are patients with a conventional pacing indication and a history of paroxysmal atrial fibrillation. A possible indication are patients with a standard indication for cardiac pacing and a high risk to develop atrial fibrillation as well as patients with drug-refractory atrial fibrillation before AV-node ablation. After pacemaker implantation the pacemaker can be programmed individually according to the onsets of atrial fibrillation observed in the patient or the patient receives a standard programming and subsequently an individual adjustment of the pacing functions. The success of preventive pacing should be assessed a each follow-up visit by interrogation of the extended diagnostic pacemaker counters. There are at present no prospective studies concerning the effects of different pacemaker programming.

关键词： Antiarrhythmic drugs Atrial fibrillation Dual-chamber pacemaker pacemaker programming Preventive pacing

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Automatic mode switching of Implantable pacemakers: II. Clinical performance of current algorithms and their programming

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PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY 2002年第7期25卷 1094-1113页

作者： Lau, CP Leung, SK Tse, HF Barold, SS Univ Hong Kong Dept Med Div Cardiol Queen Mary Hosp Hong Kong Hong Kong Peoples R China Univ Hong Kong Fac Med Inst Cardiovasc Sci & Med Hong Kong Peoples R China Kwong Wah Hosp Hong Kong Hong Kong Peoples R China Broward Gen Hosp Ft Lauderdale FL USA

While the hemodynamic and clinical significance of automatic mode switching (AMS) in patients with pacemakers has been demonstrated, the clinical behavior of AMS algorithms differ widely according to the manufacturers and pacemaker models. In general, a "rate-cutoff" detection method of atrial tachyarrhythmias provides a rapid AMS onset and resynchronization to sinus rhythm at the termination of atrial tachyarrhythmias, but may cause intermittent oscillations between the atrial tracking and AMS mode. This can be minimized with a "counter" of total number of high rate events before the AMS occurs, The use of a "running average" algorithm results in more stable rate control during AMS by reducing the incidence of oscillations, but at the expense of delayed AMS onset and resynchronization to sinus rhythm. Algorithms may be combined to fine tune the AMS response and to avoid rapid fluctuation in pacing rate. Appropriate programming of atrial sensitivity, and the avoidance of ventriculoatrial cross-talk are essential for optimal AMS performance.

关键词： automatic mode switching dual chamber pacemakers atrial flutter atrial fibrillation pacemaker programming

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Telemetry guided pacemaker programming:: Impact of output amplitude and the use of low threshold leads on projected pacemaker longevity

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PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY 1998年第11期21卷 2055-2063页

作者： Schwaab, B Fröhlig, G Schwerdt, H Heisel, A Berg, M Schieffer, H Univ Kliniken D-66421 Homburg Germany

In a prospective study a low threshold screw-in electrode (Medtronic 5078, group I, n = 9) was compared to a conventional active fixation lead (Biotronik Y60BP, group II, n = 9) to investigate whether lower pacing thresholds really translate into longer projected service life of the pacemaker. The leads were implanted in the atrium and were connected to a dual chamber pacing system which included the same ventricular lead (Medtronic 5024) and the same pulse generator model (Intermedics 294-03) in both groups. Eighteen months after implantation, atrial and ventricular pacing thresholds were measured as the charge delivered per pulse [mu C] at 0.5, 1.0, 1.5, 2.0, and 3.5 V, respectively. For chronic output programming in both channels, patients capturing at 0.5 V were set to 1.0 V, those capturing at 1.5 V were permanently programmed to 2.0 V with the double of the charge threshold as the safety margin for pacing ("safety charge"). A combination of atrial and ventricular output settings rr as optimal, if it resulted in minimum battery current drain [mu A] as measured by pacemaker telemetry. In both groups, current consumption [mu A] decreased significantly as output amplitude was decreased, exhibiting its lowest value at 1.0 V in either channel. All ventricular leads could be programmed to the optimum output amplitude of 1.0 V in groups 1 and 2. As the 2:1 "safety charge" values ere almost identical, the ventricular channel essentially contributes the same amount to the battery drain of the pacing system in both groups. In the atrium, all patients of group 1 could be programmed to the optimum output amplitude of 1.0 V with an average pulse duration of 0.42 +/- 0.15 ms. In group 2, however, ever, all patients had to be programmed to 2.0 V with a mean pulse width of 0.52 +/- 0.15 ms. With the atrial and ventricular output being optimized, the average battery drain of the whole pacing system was 12.19 +/- 0.63 mu A in group 1 versus 14.42 +/- 0.32 mu A in group 2 (P < 0.

关键词： battery telemetry safety margin pacemaker programming projected pacemaker longevity low threshold electrode

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Clinical experience of a new rate drop response algorithm in the treatment of vasovagal and carotid sinus syncope

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EUROPACE 2000年第3期2卷 245-250页

作者： Johansen, JB Bexton, RS Simonsen, EH Markowitz, T Erickson, MK Odense Univ Hosp Dept Cardiol DK-5000 Odense C Denmark Freeman Rd Hosp Reg Cardiothorac Ctr Dept Cardiol Newcastle Upon Tyne NE7 7DN Tyne & Wear England Medtron Inc Cardiac Rhythm Management Minneapolis MN USA

Dual chamber pacing has proven beneficial in patients with sudden drops in heart rate as seen in vasovagal syncope and carotid sinus syndrome. Newer algorithms for faster detection of an insidious drop in heart rate and short lasting intervention pacing at a high rate, as in the rate drop response algorithm in the Medtronic Kappa series of pacemakers, might improve the effect of pacing. Two case reports, that demonstrate the use of these rate crop response algorithms, are presented. A 24-year-old woman with recurrent episodes of syncope and repeated tilt-table tests with vasovagal cardioinhibitory outcomes had a Medtronic Kappa 400 pacemaker implanted. Syncope was abolished during repeat tilt-table testing following pacemaker implantation and proper functioning of the rate drop response algorithm. The patient has been free of syncope during follow-up apart from a single episode that occurred due to neglect of vasovagal warning symptoms. A 52-year-old man with coronary artery disease developed recurrent blackouts. Carotid sinus massage resulted in 5.5 s of asystole and presyncope. A Medtronic Kappa 700 pacemaker with a rate drop response algorithm was implanted and the patient became asymptomatic. The rate drop response algorithm is discussed in detail based upon the case reports, and recommendations are given for the use of this algorithm in patients with vasovagal syncope and carotid sinus syndrome. (Europace 2000;2: 245-250) (C) 2000 The European Society of Cardiology.

关键词： neurocardiogenic syncope vasovagal syncope carotid sinus syncope dual chamber pacing pacemaker programming rate drop response algorithm

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An intelligent system for pacemaker reprogramming

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ARTIFICIAL INTELLIGENCE IN MEDICINE 1999年第3期17卷 249-269页

作者： Lucas, PJF Tholen, A van Oort, G Univ Utrecht Dept Comp Sci NL-3508 TB Utrecht Netherlands Vitatron Med BV Dept Res & Dev NL-6950 AB Dieren Netherlands

The process of reprogramming a cardiac pacemaker can be described in terms similar to those used for describing diagnostic problem solving. In this paper, the process of reprogramming a pacemaker is formalised as a special form of abductive diagnostic reasoning, where observable findings are interpreted with respect to results obtained from diagnostic tests. The dynamics of this process is cast as a diagnostic strategy, where information is gathered in a structured fashion. This abductive theory of pacemaker reprogramming has been used as the basis for an actual system that in its present form is capable of assisting cardiologists in dealing with problems in atrial sensing and pacing. The performance of the system has been evaluated using data from actual patients. (C) 1999 Elsevier Science B.V. All rights reserved.

关键词： medical decision support medical expert systems pacemaker programming model-based reasoning abductive reasoning

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Rate-drop response programming

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PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY 1997年第3期20卷 841-843页

作者： Gammage, MD UNIV BIRMINGHAM DEPT CARDIOVASC MEDBIRMINGHAMW MIDLANDSENGLAND

Effective programming of the rate-drop response algorithm requires careful attention to the heart rate and blood pressure responses seen during diagnostic tilt testing. In order to undertake effective programming, additional tilt testing procedures may be necessary, and it is vital that the protocol should be identical on each occasion and very careful note taken of exact times of onset of symptoms and relative timing of onset of changes in heart rate and blood pressure. The algorithm settings in the Thera DR generator as delivered (factory or ''shelf'' parameter settings) must be considered nontherapeutic (an unusual situation for a pacemaker algorithm) and will require adjustment for each individual patient. Effective therapeutic settings are likely to result in an excess of pacing interventions;these, however, tend to be less symptomatic than the syncope or presyncope suffered by the patient and are generally well tolerated or not noticed.

关键词： rate-drop response algorithm pacemaker programming syncope and presyncope

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programming OF THE PACING IMPULSE IN pacemakerS CONNECTED TO STEROID LEAD SYSTEMS

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PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY 1995年第2期18卷 318-322页

作者： SCHUCHERT, A CAPPATO, R KUCK, KH MEINERTZ, T Medical Clinic Department of Cardiology University-Hospital Eppendorf Hamburg Germany

The purpose of the study was to compare the feasibility of low amplitude output programming (2.5 V/0.5 msec) 3 or more months after pacemaker implantation in patients receiving steroid and nonsteroid lead systems. Chronic pacing voltage, current, and energy thresholds were determined from 0.05- to 1.0-msec pulse duration in 44 patients with steroid lead systems, and in 36 patients with nonsteroid lead systems;all patients received pacemakers from the same manufacturer, which utilized the same programming and telemetry features. Chronaxie, pulse duration at the lowest pacing current, and energy were assessed from individual threshold curves. Steroid-eluting leads had significantly lower pacing voltage, current, and energy thresholds than nonsteroid leads. A 100% safety threshold margin could be achieved in 43 (98%) patients with steroid lead systems and in 27 (75%;P < 0.05) patients with nonsteroid lead systems with output programming of 2.5 V/0.5 msec. Chronaxie (0.22 +/- 0.17 msec vs 0.44 +/- 0.32 msec;P < 0.05 pulse duration at lowest pacing current (0.28 +/- 0.12 msec vs 0.49 +/- 0.22 msec;P < 0.05), and pulse duration at lowest pacing energy (0.31 +/- 0.17 msec vs 0.53 +/- 0.22 msec;P < 0.05) were significantly shorter for steroid than for nonsteroid lead systems. In 42 patients of the former group, a 100% safety margin could be maintained either with a 2.5 V/0.3 msec or with a 1.6 V/0.5 msec output. Conclusions Low amplitude output programming can be obtained in almost all pacemakers connected to steroid-eluting lead systems, and in a significantly higher number of patients than when connected with nonsteroid leads systems. Moreover, in most cases, a 100% safety margin can be achieved at settings as low as 1.6 V/0.5 msec or 2.5 V/0.3 msec;these different combinations offer potential different opportunies to select definitive programming and reduce pacing current requirements in patients undergoing pacemaker implantation.

关键词： STEROID ELUTING LEADS PACING THRESHOLD PACING CURRENT PACING ENERGY pacemaker programming

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INFLUENCE OF INTERNAL CURRENT AND PACING CURRENT ON pacemaker LONGEVITY

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PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY 1994年第1期17卷 13-16页

作者： SCHUCHERT, A KUCK, KH Medical Clinic Department of Cardiology University-Hospital Eppendurf Hamburg Germany

The effects of lower pulse amplitude on battery current and pacemaker longevity were studied comparing the new, small-sized VVI pacemaker, Minix 8341, with the former model, Pasys 8329. Battery current was telemetrically measured at 0.8, 1.6, 2.5, and 5.0 V pulse amplitude and 0.05, 0.25, 0.5, and 1.0 msec pulse duration. Internal current was assumed to be equal to the battery current at 0.8 V and 0.05 msec. Pacing current was calculated subtracting internal current from battery current. The Minix pacemaker had a significantly lower battery current because of a lower internal current (Minix: 4.1 +/- 0.1 mu A;Pasys: 16.1 +/- 0.1 mu A);pacing current of both units was similar. At 0.5 msec pulse duration, the programming from 5.0-2.5 V pulse amplitude resulted in a greater relative reduction of battery current in the newer pacemaker (51 % vs 25 %). Projected longevity of each pacemaker was 7.9 years at 5.0 V and 0.5 msec. The programming from 5.0-2.5 V extended the projected longevity by 2.3 years (Pasys) and by 7.1 years (Minix). Th e longevity was negligibly longer after programming to 1.6 V. Conclusion: Extension of pacemaker longevity can be achieved with the programming to 2.5 V or less if the connected pacemakers need a low internal current for their circuitry.

关键词： pacemaker programming BATTERY CURRENT INTERNAL AND PACING CURRENT pacemaker BATTERY CAPACITY

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LOSS OF pacemaker IDENTITY FOLLOWING ACTIVATION OF THE EMERGENCY VVI FEATURE

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PACE-PACING AND CLINICAL ELECTROPHYSIOLOGY 1993年第2期16卷 353-355页

作者： SCHUCHERT, A KUCK, KH Medical Clinic Department of Cardiology University-Hospital Eppendorf Hamburg Cermany

Electromagnetic signals coming from the pacemaker programmer can permanently damage multiprogrammable pacemakers. At a follow-up of a sixfold programmable VVI pacemaker (Phoenix 251-6, Pacesetter), the emergency VVI button was activated on the programmer after the programming of the pacing impulse had induced a loss of capture. The next telemetrical interrogation revealed an alteration to a threefold programmable Programmalith III. The inadvertent programming of the model number occurred, because the programming head was removed at one very specific time in the programming sequence of the emergency VVI command.

关键词： MULTIPROGRAMMABLE pacemaker pacemaker programming EMERGENCY VVI programming

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