How to read ICD episode_Dr Kush Bhagat.pptx
Download as PPTX, PDF0 likes32 views
1) The patient experienced an episode of syncope and shock delivery without an apparent trigger. Interrogation revealed multiple episodes of non-sustained VT as well as appropriately treated episodes of VT and a single shock. 2) Tracing of one episode showed a proarrhythmic effect of ramp ATP, accelerating stable VT to a rapid polymorphic rhythm causing syncope and terminated by shock. 3) Programming was modified to increase the number of intervals needed for detection to avoid undesirable outcomes, and change the first VT therapy from ramp to bursts to reduce risk of acceleration.
More Related Content
Similar to How to read ICD episode_Dr Kush Bhagat.pptx (20)
More from Kush Bhagat (20)
How to read ICD episode_Dr Kush Bhagat.pptx
- 1. How to read ICD episode?
- 2. ICD Follow Up Standard • ICD/CRT-D: 3-6 Months Suggested • Battery Voltage (and Impedance) • Capacitor Charge Time • Pacing and sensing threshold(s) for atrium, right and left ventricle (all leads) • Pacing lead impedance(s) for all leads • Shocking Impedances for defibrillation leads • Arrhythmias detected by device • % of pacing/sensing in each chamber • Therapies required for termination of SVT/VT/VF • Review of main programmed parameters • Review of any device triggered alerts • Review of hemodynamic measurements when available * Wilkoff BL, Auricchio A, et al - HRS/EHRA Expert Consensus on the Monitoring of Cardiovascular Implantable Electronic Devices (CIED): Description of Techniques, Indications, Personnel, Frequency and Ethical Considerations - May 14, 2008
- 3. Episodes Review • Start with the VF episodes/Therapy Delivred Episodes • Consider the device warnings • For each episode check: • if it is a “true” (clinical) VT/VF • the detection • the therapy • Special Functions • Other factors can influence your judgement • Preceding symptoms • Palpitations (irregular -> AF, regular -> SVT, VT) • Changes in medications • Recent reprogramming • Other diseases (co-morbidities)
- 5. Almost everything at first Sight ... 1. Present Rhythm and Rate 5. Episodes 4. Device observations / Warnings 3. Lead(s) Status 2. Battery and Capacitors
- 6. Stored Episode Review Read episodes and analyze •Related Patient symptoms •Did discriminators give correct diagnosis? •Appropriate or Inappropriate therapies? •Single Episode or Multiple Read episodes and analyze •Check for Episode Initiation •Check for terminations
- 7. Review ICD Shock Episode
- 8. Inappropriate Shock Tachycardia Absent (Over sensing) Intracardiac T/P wave Double count Extracardiac EMI Myopotentials Present (Inappropriate SVT detection)
- 9. The ICD EGM Signal • Nearfield • Electrodes are close in range • EGM Source = Tip-to-Ring / Tip-to-Coil • Narrow signal – less myocardium in range • Used for arrhythmia detection Farfield Electrodes are further in range EGM Source = Variable More myocardium covered in range Can resemble surface EKG SINUS RHYTHM VT ICD always uses a Near Field EGM source for sensing and detection to avoid oversensing
- 10. ICD EGM Options
- 12. Myopotentials •Myopotentials are high-frequency, low-amplitude electrical transients generated by skeletal muscles, including inter-costal muscles or the diaphragm. Electrograms from a stored episode showing noise on the electrogram recorded between the SVC coil and pulse generator, and the absence of noise on the V sense/pace signal (right ventricular tip to right ventricular ring).
- 13. Skeletal muscle oversensing Different sensing configurations during isometric left arm exercise showing noise seen only when the pulse generator was part of the recording suggesting that the signals are originating from in or near the pocket. •Provocative skeletal isometric exercise involving the upper extremities and abdominal muscles •Absence of noise when can is removed from the sensing circuit
- 14. Diaphragmatic myo- potentials diaphragmatic myopotentials presents as low-amplitude, high frequency signals most of the time detected exclusively in the near-field channel with no alteration in the shock electrogram. (Top) Diaphragmatic myopotential oversensing during Valsalva manoeuvre with sensitivity programmed in nominal: stored right ventricular and shock electrograms. (Bottom) Abolishment of oversensing during Valsalva manoeuvre with sensitivity programmed in least: stored right ventricular and shock electrograms.
- 15. NSVT EGM Recorded by Device due to oversensing : (Early Lead Warning ) P wave oversensing- Due to lead Dislodgement in Acute Phase Oversensing in Near Field EGM
- 16. ICD Ventricular Oversensing: Intracardiac Oversensing TWOS: T wave Oversensing
- 17. Enhanced Filter and Special Sensing Parameters to Avoid TWOS DYNAMIC SENSITIVITY ADJUSTMENT
- 18. Features to minimize T-wave oversensing
- 19. Lead failure
- 20. Lead Problems :Lead failure • It occurs during a small fraction (,8%) of the cardiac cycle •The pacing-lead impedance may be abnormal and intermittent. •signals are intermittent and have a Low frequency. •Usually, at least some signals are not cyclic. • Often, some intervals are nonphysiological, shorter than typical physiological intervals. • It often saturates the amplifier that often Signal amplitude may exceed the range of the sensing amplifier and thus appear truncated.
- 21. Lead Noise vs True VT/VF Episodes
- 22. Proprietary and confidential — do not distribute Clinical presentation Noise VF RV Near Field channel Discrimination channel (RV coil – can): Rate Correlation NO YES Technical complication Oversensing None Decision of SecureSense™ Inhibit therapy Deliver therapy • Detects and differentiates lead noise from a real VT/VF thanks to a rate comparison between the near field channel and a new reference channel (called discrimination channel) • Discrimination of lead noise in VT zone as well as in VF zone • Also able to detect non- sustained RV noises Lead Noise Discriminator : Functional principles • lead noise often generated by the following complications : Pace/Sense lead fracture Insulator rupture Loose set screw Lead not seated properly in connector
- 24. Tachycardia present • VF? – Analyse EGM to verify • VT? – Analyse EGM to differentiate SVT/VT
- 25. Shock Tachycardia Duration/ no. intervals Ignore non- sustained Detection Enhance-ments Discrimin-ation Ignore SVT • Morphology onset, stability, other logic • Single/dual chamber ATP • Terminate VT • Allow time self- term • Terminate some SVT VT Ignore slow rhythms (VT, SVT) Heart rate threshold
- 26. Characteristics real VT vs SVT A-Fib/Flutter Sinus Tach Other 1:1 SVT 200 bpm 200 bpm 200 bpm 200 bpm VT Fast V-V Cycle Length Due To… Onset Stability EGM Morphology Sudden Regular Wide / Different QRS Gradual Sudden Sudden Narrow/ Normal QRS Narrow/ Normal QRS Narrow/ Normal QRS Irregular Regular Regular
- 27. EGM to differentiate SVT/VT • Single chamber ICD – Unstable rhythm is more likely to represent AF, – Gradual acceleration is more compatible with sinus tachycardia – Sudden onset regular tachycardias – SVT (AVNRT, AT, Afl) or VT • Compare morphology of far-field channel from sinus rhythm with the one in arrhythmia • Morphology of beats that immediately follow shocks should not be relied on for comparison because of possible EGM distortion ATP
- 28. EGM to differentiate SVT/VT • ATP response • In V=A Tachycardia, During ATP – If AV dissociation – AT > AVNRT >> VT – If retrograde AV blocks – AVNRT > VT – Arrhythmia termination by ATP – supports VT >> AVRT, AVNRT – If atrial acceleration to ATP (entrainment), then after ATP stops • VAAV – AT • VVA – VT • VAV – Not helpful
- 29. EGM to differentiate SVT/VT • Dual chamber ICD – Atrial sensing • V>A vs. V<A • PVC vs. PAC initiated • If V=A, Driving chamber – A-A followed by V-V vs. V-V followed by A-A Chamber Onset ATP
- 31. Appropriate Shock • Single shock • Multiple shocks – Ineffective Initial shocks – High DFT – Incessant VT – VT Storm – Appropriate shocks for AF – If AF defibrillation ‘ON’
- 32. Multiple shocks / VT storm
- 33. Multiple shocks / VT storm
- 34. “VT Storm / Electrical Storm” • Clustering episodes of VT/VF in a short amount of time • “Electrical Storm” defined as > 3 VT episodes treated by ICD within a 24 hour period • 10 – 20% of ICD patients
- 35. Electrical Storm: ≥3 VA/24 Hours Reversible Causes AAD Catheter Ablation Neural Modulation Palliation/ Replacement Therapies •K blocker •Na blocker •β blocker •Triggers •Substrate modification • Cooling • Anesthesia • Stellate blocks • Denervation surgery •Team approach •Electrolytes •Ischemia •Inflammation •Triggers
- 36. VT storm • Treat ischemia or other precipitating factors such as HF • Judicious use of a magnet or inactivation of ICD therapy • Pharmacological therapy for VT (e.g. β-blockers, amiodarone); possible catheter ablation • IABP or hemodynamic support for hypotension • Replace electrolytes (K+, Mg2+) • Left stellate ganglionic blockade in selected patients • Identify specific diseases that may need specific therapy (e.g. recurrent VT in Brugada syndrome - isoproterenol and quinidine)
- 37. SYNCOPE WITH NO APPARENT SHOCK
- 39. CASE EXALMPLES
- 40. Background • 67-year-old man implanted with a single-chamber ICD for the management of advanced ischemic cardiomyopathy complicated by repetitive episodes of non- sustained VT. • He was seen for evaluation of syncope and delivery of an electric shock.
- 41. FastPath Summery: Quick look overview
- 42. Episode Summary: Any VT/VF episode? Therapy delivered?
- 43. Diagnostics Summary: How many % paced or sensed?
- 44. Parameters: Zone, rate cut-off, # of interval for detection, discriminators and therapies programmed
- 45. Parameters: ATP and dynamic sensitivity details
- 46. Episode Details: Diagnosis of discriminators: VT or SVT? What therapies have been delivered? ATP or shock? Burst or Ramp ? Successful or failed?
- 47. 1 2 3 4 5 Observe from Tracing
- 48. Observe from Tracing Sudden onset of a regular monomorphous tachycardia, with change in morphology; probable VT; initial cycles classified unbinned because of discordance between the instantaneous (fast) and average of the 4 previous cycles (slow) After 16 T classified cycles, the VT counter if full First therapy corresponding to the VT zone; it is a ramp (pacing with cycles shortening from 252 to 200 ms) Instead of termination, the ventricular rhythm is markedly accelerated, detected in the VF zone and become polymorphous After 12 F classified cycles, an episode of VF is detected; the capacitors begin to charge 2 3 4 5 1
- 49. 6 7
- 50. Observe from Tracing End of charge and delivery of 30 J shock End of arrhythmia and return to sinus rhythm diagnosed 7 6
- 51. Comments • This patient had ischemic cardiomyopathy with multiple episodes of asymptomatic or nearly asymptomatic NSVT (4 to 20 cycles). • Never experienced an episode of sustained VT or of syncope before the implantation. • After implant, he presented loss of consciousness and electric shock in absence of apparent triggering factor. • Interrogation revealed many episodes of NSVT, as well as a few episodes treated by ATP and a single episode treated by a shock. • Tracing revealed a proarrhythmic effect of the ramp and acceleration of stable VT to a rapid, polymorphous ventricular arrhythmia causing syncope and terminated by a life-saving electric shock. • The priority in the management of these episodes of NSVT was to promote their spontaneous termination, and to program a sufficient number of cycles to avoid this undesirable outcome.
- 52. • If acceleration of an arrhythmia is an immediate risk, it should be terminated with one maximum energy shock to avoid the delivery of multiple electric shocks as this will compromise the survival in long-term. • The device programming was, therefore, modified by an increase in the number of cycles needed to fill the counters, from 16 to 30 in the VT, and from 12 to 30 in the VF zones. This should offer a wide enough margin and promote a spontaneous termination without increasing significantly the risk of syncope, should the tachyarrhythmia be sustained. • The first therapy in the VT zone was a ramp, which may be surprising and against the latest guidelines, which clearly favor the programming of bursts, apparently more effective from the standpoint of the terminations/accelerations ratio. • Furthermore, the coupling and the decrement of that ramp were probably both excessively aggressive, since the last pulse was delivered at the shortest coupling interval of 200 ms. • The programming was replaced by 3 bursts, followed by the highest amplitude shocks in the VT zone. Comments
- 53. Wr Wrap-up Overview: What parameters have been changed?
- 54. • ICD is a medical breakthrough but has a complex functioning • Adequate therapy prolongs survival but unnecessary therapy increases morbidity and mortality • Appropriate function requires adequate mechanical components (Lead), electrical function (battery and capacitor), software functioning (detection algorithms), and substrate (appropriate DFT and safety margin) • Knowledge and know-how of all 4 components of ICD therapy is essential for the caregiver
- 55. Thank you