Cardiac rhythm detailed monitoring by an implanted pacemaker: The iecg solution

Transcription

1 Cardiac rhythm detailed monitoring by an implanted pacemaker: The iecg solution Francesco Zanon, MD, FESC, FHRS Arrhythmia and Electrophysiology Unit, Cardiology Dept. Santa Maria della Misericordia General Hospital Rovigo - Italy

2 Non-symptomatic paroxysmal AF is often undetected and untreated. This increases the thromboembolic risk, which is a major concern in patient care. Healey JS N Engl J Med 2012;366: Diagnostic information provided by an implanted device would allow continuous tachyarrhythmia monitoring and prompt identification of patients with silent AF, where prophylactic hypo-coagulation can be indicated. A new type of electrogram, available in special dual-chamber pacemakers and referred to as intracardiac ECG, might prove a valuable tool in the detection and characterization of tachyarrhythmia episodes in the patient s daily life.

3 The iecg is a multipolar integrated signal derived by the whole set of electrodes available in dual-chamber pacing. ECG

4 AV conduction with narrow QRS the QRS time-course is the same as on the surface ECG. 40 ms delay 97 ms

5 LBBB RBBB 35 ms delay 70 ms delay 150 ms 130 ms Surface and intracardiac QRS shows similar time-course iqrs mirrors the surface QRS time-course

6 The iqrs properties depend on waveform origin and conduction pathway I II III avf iecg ip iqrs iqrs' ip Sinus rhythm vs. PVC

7 The iqrs properties depend on waveform origin and conduction pathway I II III avf Vs iecg ip ip ip ip ip ip ip ip ip iqrs' ip ip iqrs' iqrs iqrs' iqrs ip ip 3 rd degree AVB with two escape rhythms 2 different types of escape beats, LBBB and RBBB pattern

8 iqrs and surface QRS feature the same time-course with either intrinsic or evoked complexes AV 200 AV 120 pseudofusion fusion

9 His-bundle pacing 114 ms I II III HISp As HISs APEXs iecg iqrs ip Spike-Q delay

10 Threshold test with Hisian pacing (VVI) iqrs duration 95 ms Sinus P-waves Retrograde P-waves iqrs duration 110 ms

11 His-bundle capture Para-Hisian capture His-bundle capture I II III avf As Vp iecg dv/dt

12 Biventricular pacing surveillance 248 ms 256 ms 170 ms

13 Pacing failure recognition with high sensitivity and specificity, in ventricle: The striking difference in the iecg signal detected with pseudofusion or true pacing failure could prevent false alarms of capture loss, ensuring maximum sensitivity at the same time I II III avr markers Vp Vs Vs Vp As iecg VVI Intrinsic conduction Pseudofusion in VDD

14 and atrium: I II III avr markers Ap As Vp As Vs iecg Fusion Pseudofusion in DDD (AV delay = 350 ms) Intrinsic conduction Fully evoked QRS after atrial pacing failure

15 The iecg in the characterization of tachyarrhythmia episodes High ventricular rate No major changes in iqrs waveform SVT Sinus rhythm AVRT

16 High ventricular rate Substantial changes in iqrs waveform VT or SVT with aberrant conduction Sinus rhythm VT

17 Sinus rhythm Non-tolerated VT TVI iecg I II III

18 Sinus rhythm AF

19 AF recorded by an implanted pacemaker

20 CONCLUSIONS The iecg is an advanced and powerful solution for continuous monitoring of cardiac activity in daily life. In addition, several applications are foreseen in the autoregulation of the pacing function.