Leadless Pacing Osama Diab Assistant Prof. of Cardiology Ain Shams University Egypt
The weakest link in Pacemaker system the lead. The more the leads the more the complications Dislodgement Fracture Insulation break Infection Extraction issues Vein thrombosis CS dissection (CRT) Cardiac perforation Pneumothorax Endocarditis Valve injury
Risk factors for lead complications in cardiac pacing: A population-based cohort study of 28,860 Danish patients The incidence of any lead complication was 3.6% (3 ms follow up) Risk factor Adjusted Odds Ration 95% CI Chronic HF as indication 3 2.1-4.3 Implantation in a nonuniversity center Inexperienced operator with <25 implantations 1.4 1.2-1.6 1.6 1.3-2 Single-lead RA device 1.4 1.1-1.8 Dual-chamber pacing 1.6 1.4-1.9 CRT-P 3.3 2.4-4.4 Passive-fixation RA lead 2.2 1.7-2.9 Heart Rhythm, Volume 8, Issue 10, Pages 1622-1628, October 2011
Lead Dislodgement During Follow-Up in Nonthoracotomy Requiring Implanted Devices Trial Year Successful Implants, n All Events, n (%) Duration, months Nonthoracotomy ICD systems AVID 1997 593 8 (1.5) 27 ± 13 CAT 2002 50 2 (4.0) 0.5 DEFINITE 2004 227 6 (2.6) 29 ± 14 Total 870 16 (1.8) Nonthoracotomy CRT systems MIRACLE 2002 526 31 (5.9) 6 MIRACLE ICD 2003 379 11 (2.9) 6 CARE-HF 2005 390 11 (2.8) 0.5 RethinQ 2007 172 13 (7.6) 6 REVERSE 2008 621 66 (10.6) 12 MADIT-CRT (CRT arm) 2009 1,007 44 (4.4) 0.5 Total 3,095 176 (5.7) J Am Coll Cardiol. 2011;58(10):995-1000. doi:10.1016/j.jacc.2011.06.007
Complications Related to Coronary Sinus in Recipients of a Nonthoracotomy CRT Device With or Without Defibrillator Trial Year Patients Undergoing Implantation Coronary Vein Dissection, Perforation or Tamponade Coronary Vein Dissection Coronary Vein Perforation Coronary Vein Tamponade MIRACLE 2002 568 35 (6.2%) 23 (4.0) 12 (2.0) NR MIRACLE ICD 2003 421 19 (4.5) 15 (3.6) 4 (1.0) NR COMPANION 2004 1,212 22 (1.8) 5 (0.4) 12 (1.0) 5 (0.4) CARE-HF 2005 404 6 (1.5) 5 (1.2) NR 2 (0.5) RethinQ 2007 176 1 (0.6) 1 (0.6) NR NR REVERSE 2008 642 3 (0.5) 3 (0.5) NR NR MADIT-CRT (CRT arm) 2009 1,089 5 (0.5) 5 (0.5) NR NR Total 4,512 91 (2.0) 57 (1.3) 28 (1.3) 7 (0.4) J Am Coll Cardiol. 2011;58(10):995-1000. doi:10.1016/j.jacc.2011.06.007
Pneumothorax Related to Implantation of Nonthoracotomy Devices Trial Nonthoracotomy ICD systems Year Patients Undergoing Implantation, n Events, n (%) AVID 1997 539 6 (1.1) DEFINITE 2004 227 2 (0.9) MADIT-CRT (ICD arm) 2009 731 6 (0.8) Total 1,497 14 (0.9) Nonthoracotomy CRT systems MIRACLE 2002 568 1 (0.2) MIRACLE ICD 2003 421 3 (0.7) CARE-HF 2005 404 2 (0.5) RethinQ 2007 176 2 (1.1) REVERSE 2008 642 4 (0.6) MADIT-CRT (CRT arm) 2009 1,089 18 (1.7) Total 3,300 30 (0.9) J Am Coll Cardiol. 2011;58(10):995-1000. doi:10.1016/j.jacc.2011.06.007
Mortality and complications of lead extraction Circulation: Arrhythmia and Electrophysiology. 2010; 3: 413-424
Lead extraction versus lead abandonment: Risk versus Risk Risk of Lead Extraction Circulation: Arrhythmia and Electrophysiology. 2010; 3: 413-424
Complication Rates Associated With PM or ICD generator Replacements and Upgrade Procedures Patients without lead addition: Patients with 1 or more lead addition: Circulation. 2010; 122: 1553-1561
Major Complication Rates by Lead Procedure P=0.004 Circulation. 2010; 122: 1553-1561
Lead complications in paced population Infection Up to 1.2 within year after implantation Up to 5% of entire population with endocarditis 1% risk of death and 2% risk of major complications at lead extraction Lead interaction with heart and vessels 20% of implanted pts have TR Up to 25% venous thrombosis/stenosis Lead failure Up to 21% within 10 years after implantation
Recalls of Medtronic and St Jude leads stimulated increased interest and research in the area of leadless pacemakers Recalls of: Medtronic s Sprint Fidelis leads on October 2007 due to high rate of fractures and breaks. St. Jude s Riata leads on November 2011 due to high rate of failure and erosion.
Totally self-contained intracardiac pacemaker Dpickler et al, Journal of Electrocardiology Volume 3, Issues 3 4, 1970, Pages 325 331 Miniaturization technology Long life battery Totally contained inside the RV Introduced and removed transvenously
Energy source Endocardial receiver unit Ultrasound energy EBR technology Magnetic energy Induction technology
Intracardiac self contained leadless PM
Ultrasound energy: Energy transfer from an US transmitter to a receiver electrode in the heart. Temporary pacing was successful and safe in animal and human studies using external US generator. J Am Coll Cardiol. 2007;50(9):877-883.
1- Energy transfer efficiency: - A major limitation esp in PM dependant pts 2- US generator: - Apart from WiCS (used for CRT), current generators are external only 3- Transmission beam: - Impact on threshold safety margin. - Thermal effect? 4- Acoustic window: - Body positions and respiratory phases - Obesity, COPD 5- Sensing function: - Not yet addressed Heart rhythm, Vol. 6, No. 6, June 2009
WiCS (Wireless Cardiac stimulation) 9 mm
WiSE-CRT is a 100 patient feasibility and safety trial being conducted in Europe demonstrating biventricular pacing capture with WiCS (Wireless Cardiac Stimulation System) More than 16 patients successfully treated to date include those with: - Acutely failed CS lead placement - Chronically failed CS leads - Patients upgraded from dual-chamber defibrillators. - Patients who have not yet responded to conventional CRT.
Induction technology Magnetic field generated from a transmitter unit to a receiver unit0 in the heart converted into electric stimulation Only in animal models A transmitter unit implanted subcutaneously (primary coil) An endocardial receiver unit implanted in the RV apex (secondary coil) The device can be programmed by telemetry like a conventional PM PACE 2009;32:177 183 Europace 2012, online 1 st of Oct (Wieneke et al.)
High Density Battery System Totally self contained intracardiac PM Intracardiac VVIR system Cylinder shaped 2.5 cm Steerable catheter~20f 7-10-yr longevity Programmable Placed within RV Basic device and arrhythmia diagnostics Output Amplitude: nom 2.0V; max 5.0V
Percutaneous intracardiac leadless pacemaker <1x2.4 cm
Intracardiac leadless PM: Wireless connectivity to smart phones
Intracardiac leadless PM In a 16-sheep animal study, Medtronic monitored the electrical behavior of animals receiving the device for 24 weeks. At its conclusion, the study showed no adverse events, demonstrating similar pacing results to currently available pacemaker leads.
Functionality Implant Support: Impedance measurement, P/R-wave amplitude, pacing threshold Diagnostics Percent paced/sensed Battery longevity Pacing data (threshold/impedance) Extensible to rate response data Electrode Integrity Monitor Rate Hysteresis Noise Reversion Holter Mode
Intracardiac leadless PM Avoid lead complications Avoid pocket complications
No surgery Fewer acute and chronic complications (no lead) Less exposure to radiation Cosmetic benefit (invisible) More MRI conditional Femoral venous access (avoid subclavian anomalies) No system connections Short hospital stay
Large diameter sheath Embolization Repositioning difficulty for high thresholds Pediatric application Memory limitation Longevity limitation (abandon vs explant)