A Pacemaker AutoSense Algorithm with Dual Thresholds

  • Kim, Jung-Kuk (Department of Electronics Engineering, Myongji University) ;
  • Huh, Woong (Department of Electronics Engineering, Myongji University)
  • Published : 2002.12.01

Abstract

A pacemaker autosense algorithm with dual thresholds. one for noise or tachyarrhythmia detection (noise threshold, NT) and the other for intrinsic beat detection (sensing threshold. ST), was developed to improve the sensing performance in single pass VDD electrograms. unipolar electrograms, or atrial fibrillation detection. When a deflection in an electrogram exceeds the NT (defined as 50% of 57), the autosense algorithm with dual thresholds checks if the deflection also exceeds the ST. If it does, the autosense algorithm calculates the signal to noise ratio (SNR) of the deflection to the highest deflection detected by NT but lower than ST during the last cardiac cycle. If the SNR 2, the autosense algorithm declares an intrinsic beat detection and calculates the next ST based on the three most recent intrinsic peaks. If the SNR $\geq$2, the autosense algorithm checks the number of deflections detected by NT during the last cardiac cycle in order to determine if it is a noise detection or tachyarrhythmia detection. Usually the autosense algorithm tries to set the 57 at 37.5% of the average of the three intrinsic beats, although it changes the percentage according to event classifications. The autosense algorithm was tested through computer simulation of atrial electrograms from 5 patients obtained during EP study, to simulate a worst sensing situation. The result showed that the ST levels for autosense algorithm tracked the electrogram amplitudes properly, providing more noise immunity whenever necessary. Also, the autosense algorithm with dual thresholds achieved sensing performance as good as the conventional fixed sensitivity method that was optimized retrospectively.

Keywords

References

  1. PACE v.13 Clinical evaluation of an automatic sensitivity adjustment feature in a dual chamber pacemaker Wilson J;Love C;Wettenstein E https://doi.org/10.1111/j.1540-8159.1990.tb02017.x
  2. PACE v.15 Reliability of an automatic sensing algorithm Berg M;Frohlig G;Schwerdt H;Becker R;Schieffer H https://doi.org/10.1111/j.1540-8159.1992.tb02986.x
  3. PACE v.19 Evaluation of autosensing as an automatic means of maintaining a 2:1 sensing safety margin in an implanted pacemaker Castro A;Liebold A;Vincente J;Dungan T;Allen J https://doi.org/10.1111/j.1540-8159.1996.tb03211.x
  4. NASPE Automatic gain control in pacemaker sensing Kim J;Haefner P;Stockburger M;Spinelli J
  5. 20th Cardiostim Nowak B;Fellmann P;Maertens S;de Metz K;Mols R;Bruls A;Geil S;Voigtlander T;Himmrich E;Meyer J
  6. 20th Cardiostim v.74-2 Behavior of an automatic sensing algorithm for single-pass VDD(SVDD) atrial electrograms Kim J.;Senden J;Willems R;Kammeijer W
  7. PACE v.23 Influence of autothreshold sensing and sinus rate on mode switching algorithm behavior Wood M;Ellenbogen K;Dinsmoor D;Hess M;Markowitz T https://doi.org/10.1046/j.1460-9592.2000.01473.x
  8. PACE v.21 Should unipolar leads be implanted in the atrium? A Holter electrocardiographic comparison of threshold adapted unipolar and high sensitive bipolar sensing Wiegand U;Schier H;Bode F;Brandes A;Potratz J https://doi.org/10.1111/j.1540-8159.1998.tb00249.x
  9. PACE v.24 Combipolar sensing in dual chamber pacing: Is there still a need for bipolar leads in the atrium? Linde C;Markewitz A;Strandberg H;Larsson B;Binner L;SchUller H https://doi.org/10.1046/j.1460-9592.2001.01664.x
  10. PACE v.21 Atrial synchronous ventricular pacing with single lead: Realiability of atrial sensing during physical activities, and long-term stability of atrial sensing Faerestrand S;Ohm O https://doi.org/10.1111/j.1540-8159.1998.tb01103.x
  11. PACE v.21 Extensive variation in the signal amplitude of the atrial floating VDD pacing electrode Sun Z;Stjernvall J;Laine P;Toivonen L https://doi.org/10.1111/j.1540-8159.1998.tb00276.x
  12. PACE v.24 Clinical relevance of loss of atrial sensing in patients with single lead VDD pacemakers Van Campen C;de Cock C;Huijgens J;Visser C https://doi.org/10.1046/j.1460-9592.2001.00806.x
  13. PACE pacing Clin Electrophysiol v.17 Long-tern stability of P-wave sensing in single lead VDDR pacing: Clinicla versus subclinical atrial undersensing Lau C;Tai Y;Leung S;Leung W;Chung F;Lee I https://doi.org/10.1111/j.1540-8159.1994.tb03761.x
  14. PACE v.24 Paradoxical undersensing at a high sensitivity in dual chamber pacemakers Willems R;Holemans P;Ector H;Were F https://doi.org/10.1046/j.1460-9592.2001.00308.x
  15. PACE v.25 Rate dependent far-field R-wave sensing in an atrial tachyarrhythmia therapy device Collins R;Haugh C;Casavant D;Sheth N;Brown L;Hook B https://doi.org/10.1046/j.1460-9592.2002.00112.x
  16. PACE v.13 Implantable Lead Registry. Survival of implantable pacemaker leads Furman S;Benedek ZM https://doi.org/10.1111/j.1540-8159.1990.tb06915.x
  17. Cleve Clin J Med v.61 Durability of bipolar coaxial endocardial pacemaker leads compared with unipolar leads Helguera ME;Pinski SL;Maloney JD;et al. https://doi.org/10.3949/ccjm.61.1.25
  18. PACE v.18 Multicenter experence with a bipolar tined polyurethane ventricular lead Hayes DL;Graham KJ;Irwin M et al. https://doi.org/10.1111/j.1540-8159.1995.tb04740.x
  19. PACE v.19 Apprasial of pacing lead performance from the Danish Pacemaker Register MollerM;Arnsbo P. https://doi.org/10.1111/j.1540-8159.1996.tb04211.x
  20. PACE v.20 Long-term clinical experence of patients implanted with two types of bipolar polyurethane ventricular leads Zweibel S;Gross J;Furman S
  21. Incidence and predictors of pacemaker dysfunction with unipolar ventricular lead configuration v.24 Wiegand U;Bode F;Bonnemeier H;Tolg R