device malfunction: pathophysiology & management implications · observation •risk of...
TRANSCRIPT
Device Malfunction: Pathophysiology & Management Implications
www.brighamandwomens.org/heart
Melanie Maytin, MD, MSc, FHRSBrigham and Women’s Hospital
Boston, MA
Disclosures: • Research grant from Boston Scientific• Participate in industry-sponsored research with Biotronik,
Boston Scientific, and Medtronic• Consultant for Biotronik, Medtronic, Spectranetics and St.
Jude Medical.
Dear Doctor
IMPORTANT PATIENT MANAGEMENT INFORMATIONNovember 2005
Dear Doctor
Physician CommunicationImportant Physician AdvisoryOctober 6, 2005
Dear Doctor:
Definitions
• Class I recall: a situation in which there is a reasonable probability that the product will cause serious adverse health consequences or death.
• Class II recall: a situation in which the product may cause temporary or medically reversible adverse health consequences or where the probability of serious adverse health consequences is remote.
• Class III recall: a situation in which use of or exposure to the product is not likely to cause adverse health consequences.
Why advisory/recall information is useful
• Implications of failure & timing of failure can be quite variable and patient-dependent
• Majority of advisory announcements provide the physician with:
– Estimated risk of failure
– Details on the cause for the failure
– Potential management recommendations (software or RAMware)
Functions that can fail
• Sensing – Lack of bradycardia support– Inability to detect true ventricular arrhythmias
• Pacing– Lack of bradycardia support– Ineffective anti-tachycardia pacing (ATP)– Ineffective CRT
• Defibrillation– Failure to terminate a tachyarrhythmia – May accelerate slower tachycardias– INAPPROPRIATE SHOCKS
Risk vs. RiskAdvisory Devices/Leads
Observation
• Risk of device/lead failure- Failure to pace- Failure to shock- Inappropriate shock- Rapid pacing
Replacement
• Risk of device/lead replacement- Infection- Damaged hardware- Bleeding, perforation, death- ? Reliability of new device/lead
Risk of Observation
Risk of Replacement
Lower Procedural Risk,Higher Future Risk?
(Specific to individual patient)
Higher Procedural Risk,Lower Future Risk
(Specific to the person performing the
extraction)
Risk vs. Risk
The “A” Word
• Over 30% of physicians would replace a device on Advisory even if the failure rate was similar to any new device they would implant
Maisel, PACE 2004; 27:437–442
NASPE Physician Survey
Opening the Pocket is Not Without Risk
Replace Registry: 4% risk of major complication associated with simple generator change alone
Poole JE et al: Circulation 2010,122:1553-1561
• 17 surveyed centers• 2915 patients had recall devices (Medtronic Marquis®)• 533 (18.3%) who had advisory ICDs • A mean of 2.7 months' follow-up after ICD generator replacement• Complications occurred in 43 patients (8.1%)• Major complications attributable to advisory device replacement requiring
reoperation occurred in 31 patients (5.8%), with death in 2 patients after extraction for pocket infection
• Minor complications occurred in 12 patients (2.3%)• There were 3 (0.1%) advisory-related device malfunctions reported, without clinical
consequences.
.
Telectronics Accufix Pacing Lead
• Recalled in November 1994 after 2 deaths, 2 non-fatal injuries (Class I Recall)
• 45,000 worldwide implants
• Risk of wire fracture/protusion of electrically inactive J retention wire
• Issue: More deaths documented due to extraction than lead malfunction
Accufix
• Actual risk of fracture was low and risk of perforation of wire even lower
• Extractions performed by inexperienced operators at center not organized to perform the procedure
Why did this happen?
Accufix
• Assess the risk of leaving leads vs. Removing leads
What did we learn?
Advisory Leads
• Leads that can cause harm
• Leads that can fail
Leads that have failed(abandon vs. replace)
How Do Our Patients Decide?
Amin MS, et al., JAMA 2006
How Do Our Patients Decide?
Gula LJ, et al., Am Heart J 2007Priori SG, et al., J Cardiovasc Electrophysiol 2009
How Do Our Patients Decide?
• There is no one right answer: An individual decision
• What is the advisory?
• What are the consequences of lead failure?- Loss of lead function: pacing, defibrillation- Lead malfunction: inappropriate shocks
• What is the patient’s prognosis?
Fidelis® Lead
• 6.6 French lead• True bipolar• Isodiametric• Backfilled coils• Reduced insulation &
stiffness• Approved by FDA in
September 2004
Heart Rhythm 2007;4:892-896
Fidelis® Lead Failure RateContinues to Increase
• October 2007: Sprint Fidelis® lead removed from market due to a failure rate of 2.3% at 30 months
• October 2008: Farwell et al – hazard of Fidelis fracture increased with time by a power of 2.74
• April 2009: Krahn et al – accelerating rate of failure with 3.91% failure rate at 32 months
• May 2009: Hauser et al. – estimated 3 year survival of 87.9%
Medtronic Sprint Fidelis Performance reportsFarwell, Heart Rhythm 2008Hauser, Heart Rhythm 2009
Carelink® Plus @ 120 months: 19.2% failure rateSLS @ 96 months: 21.5% failure rate
6949: May 2015
Are All Patients The Same?
NO
Rates as high as 48% at certain centers
6949: May 2015
Lead survival varies with patient age
6949: May 2015
Lead survival varies with patient gender
6949: May 2015
Birnie et al, Circulation 2011
Future Estimated 10-year Failure Rate
• 3,169 leads at 11 Canadian Centers
• 3, 4, 5 year failure rate: 5.3%, 10.6%, 16.8%
• Lead failure rate accelerating by a non linear hazard of 1.38
• Predictors of failure:- female gender- axillary/subclavian access vs. cephalic- previous lead fracture
Real World Dilemma
• Many Fidelis® patients are approaching or have reached ERI
• What should they do?
Options at the Time of Generator Change
• Generator change only
• Add a pace-sense lead
• Abandon advisory lead and add a new lead
• Extract advisory lead and add a new lead
For Fidelis® Leads That Appear to Be Functioning Normally
557 Extractions100% Success0 major Cx0 Mortality
Implications
• If the ultimate failure rate of the Sprint Fidelislead will be significantly higher then currently reported, recommendations regarding lead management, especially at the time of generator change, should be reconsidered
Lovelock, Heart Rhythm 2012
Risk of Lead Observation
Risk of Extraction
Risk vs. Risk
Lower Procedural Risk,Higher Future Risk?
Higher Procedural Risk,Lower Future Risk?
To make a decision data is requiredWhat will the actual failure rate be??
Birnie et al, Circulation 2011
Future Estimated 10-year Failure Rate
Up to 55% Failure rate at 10 years!
Fractures Found in Prophylactically Removed Sprint Fidelis® ICD Leads: The Iceberg?
• Of leads w/o “clinical” electrical abnormalities, 20% were found to have structural and/or electrical abnormalities on RPA
• 4 leads with >1 abnormality (20%)– 10 proximal conductor fractures
– 7 distal conductor fractures
– 1 SVC defibrillator fracture
– 5 RV defibrillator fractures
– 1 lead with proximal conductor “wear”
Maytin, Heart Rhythm 2012
Adding a Pace-Sense Lead:Not a Good Idea!
• HV Conductor Survival After Pace-Sense Conductor Fracture
• 22.3% HV Conductor Failure Rate• Therefore adding a Pace-Sense lead is not a good option
Documentation
• Document the discussion
• Document what choices were discussed
• Document that the risks of each were discussed
• Document that all questions were answered
• Document that the decision was the patient’s choice
The “Letter”
• In December 2011, the FDA issued a Class I Recall of Riata® and Riata ST® ICD leads.
• Externalized cables: outside-in & inside-out
• Riata ST®: flat wire shock coils with silicone backfill
The Problem With Returned Product Analysis (RPA)
RPA Externalized Conductors 8F 0.31%, 7F 0.11%
Dutch Experience
• 1029 leads
• Externalized conductors: 14.3%- 1500: 21.4%- 7000: 8.0%
• Electrical Failure:- Externalized conductors: 10.9%- No Externalized conductors: 3.5%
Theun et. al. Circ Arrhyth, 2012)
Riata® Questions
• Externalized Conductors- What is the actual incidence?- Should we be screening? - What do we do when we find it?- Will they fail electrically?
• What is the actual failure mechanism?
• How do we follow Riata® leads?
• How to extract Riata® leads?
DATA – Riata Lead Malfunction
Study N Structural failure (cable externalization)
Electrical failure*
Electrical failure +Structural abnormality
Electrical failure with no structuralabnormality
Kodoth 165 15% - 0 -
Parvathaneni 87 33% - - -
Abdelhadi 1081 - 49 (4.5%) (8) 0.74% 3.8%
Parkash 4500 - 227 (5.0%) 54 (1.2%) 173 (3.8%)
Steinberg 284 69 (24%) 36 (12.7%) 6 (2.1%) 23 (8.1%)
Theuns 1029 147 (14.3%) - 16 (10.9%) 3.5%
Sung 1403 - 47 (3.3%) - -
Steinberg 141 12 (8.5%) 9 (6.4%) - -
Larsen 239 10 (4.2%) 20 (8.4%) - -
Hayes 776 20 (2.8%) 47 (6.6%) - -
Time to structural failure seems to occur predominantly after 5 years;Time to electrical failure is unknown
*abnormal impedance, elevated threshold, noise or inappropriate shock
Mechanism of Failure
Parkash, Heart Rhythm 2015
Mechanism of Failure
Parkash, Heart Rhythm 2015
Monitoring
• Currently, there are no known predictors or early warning signs for failure of this lead
Monitoring• Currently, there are no known predictors or early
warning signs for failure of this lead
• Increased monitoring is the only way of detecting a problem (and may not detect HV problems)
• 1-3 months via remote
• Every 3 months for an in-clinic visit if remote monitoring is not possible
• Older generation devices need an adaptor for remote monitoring, which has not been uniformly available
Radiographic Screening?
• Routine screening of all patients?
• Screening technology:- X-ray?- Fluoroscopy?
• Timing:- At some initial point and then how often?- Prior to generator change?
Radiographic Screening• Radiographic screening
Pro:
– Diagnose structural lead failure
– May be a marker of future electrical lead failure
– Long-term impact (electrical and mechanical) of extruded cables unknown
Con:
– Given the limited data, the risk of intervention in a electrically normally functioning lead may not be worth the benefit.
– The risk of radiation exposure may not be warranted if cable extrusion will not change clinical management
Current recommendations• Canadian HRS Device Committee does not recommend
routine screening
• The FDA has recommended routine screening
- Will findings result in a change in management?(the FDA recommends not acting on findings. Then why screen!)
- The mechanism of failure may be unrelated to presence or absence of externalized cables
• Therefore, radiographic screening should only be performed if the findings will result in some action
Prior to Generator Change?
• At the time of generator change the patient is already exposed to the risk of opening the pocket
• Should screening be performed prior to planning the procedure?- generator change only- generator change plus lead revision?
• Screening?- fluoroscopy- High voltage, full output, synchronized shock
Externalized Conductors?
• What do you do with leads that demonstrate normal electrical function but externalized conductors?
Hauser, Heart Rhythm 2012
Potential Issues with Extruded Cables
• Electrical failure
• Cable migration
• Electrical interference
• Thrombus formation
• Cable fibrosis making future extraction more difficult
All Unknown!
Maytin, EP Lab Digest 2014
How Do Our Patients Decide?
• There is no one right answer: An individual decision
• What is the advisory?
• What are the consequences of lead failure?- Loss of lead function: pacing, defibrillation- Lead malfunction: inappropriate shocks
• What is the patient’s prognosis?
Risk of Observation
Risk of Replacement
Lower Procedural Risk,Higher Future Risk?
(Specific to individual patient)
Higher Procedural Risk,Lower Future Risk
(Specific to the person performing the
extraction)
Risk vs. Risk
Maytin, Heart Rhythm 2014
Important InformationFor The Patient
• Nature of the advisory
- Cable externalization estimated at 10-25% depending on lead model
- All-cause electrical lead failure rate is approximately 1.5-2%/year, based on current data1,2,3
- The risk of abnormal function may be independent of cable externalization
1. Abdelhadi et al. 20122. Parkash et al. 20123. Sung et al. 2012
Lead Management Options
• Observation
• Lead replacement- addition of a new ICD lead- addition of a new PS lead*- extraction with replacement
*Not a recommended option. The HV cables appear to be a more vulnerable component. Abandonment similarly undesirable for aforementioned reasons.
Extraction vs. Lead Addition
• Extraction- higher risk of procedure- elimination of future issues
• Addition- lower risk of procedure (although not that much higher based on the REPLACE study!)- potential future risk of abandoned lead with extruded cable:- degradation of HV ETFE insulation resulting in “short” internally or with a new lead- thrombus formation on extruded cables- fibrosis of extruded cables making future extraction more difficult
Are All “Down-sized” ICD Leads the Same to Extract?
No(Riata® is not the same as Fidelis®!)
Tie Each Component(Including HV Cables)
Lead Extraction ConsiderationsRiata® 1500 series is not backfilled
– May have more ingrowth at coils
– May require upsizing
– May require outer sheath use
– Riata 7000 series is backfilledImage Source: SJM Design Advantage Publication, Distributed October 2007
Silicone Riata ST Silicone Riata
Extruded Cables Fibrotic Shocking Coil
Lead Extraction Considerations
Courtesy of Roy John, MD, PhD
Lead Extraction Considerations
“Snow plowing” of extruded cables
Courtesy of Roger Carillo, MD
Courtesy of Roger Carillo, MD
Courtesy of Roger Carillo, MD
Durata
• The benefit of cardiac resynchronization therapy (CRT) depends upon initially successful and chronically stable coronary sinus lead placement.
• Active fixation coronary sinus (CS) leads limit lead dislodgement and represent an attractive option to the implanter.
• The Attain StarFix® 4195 lead (Medtronic, Inc., Minneapolis, Minnesota) received FDA approval in June 2008 as the first active fixation CS lead.
• Since its market release in August 2008, approximately 16,400 leads have been implanted in the United States.
Illustration demonstrating active
fixation mechanism of Attain
StarFix® 4195 lead. The image to
the far left shows the lead with the
lobes retracted. As the blue push
tubing is advanced, it compresses a
slotted area of the tubing forming
lobes. When deployed, the lobes
range from 5 to 24F in diameter.
• 42F with HCM s/p surgical myectomy, LBBB, moderate-to-severe LV dysfunction (EF 30-35%) and NYHA class III HF
• Initial CRTD implant 2007
• Presented 1 year later with LV lead dislodgement
• Device system revision with implantation of Attain StarFix® 4195 lead
• Presented 16 months later with local CIED infection
• Underwent TLE attempt at OSH
• Atrial lead, ICD lead & generator removed without complication
• Lobes of 4195 could not be retracted
• Lead removal attempted with 12F laser -unsuccessful
• Lead cut & allowed to retract
• Patient referred for TLE
Maytin, et al. PACE 2012
THERE IS NO ONE RIGHT ANSWER
The goal is to avoid undue patient stress and harm while identifying the patients at greatest risk of malfunction.
It is Important to Know When to Ask for Help
Mentorship
• Crucial to a successful career in lead extraction
• Discussions around difficult clinical situations can be very valuable and allow clinicians to arrive at the most appropriate treatment approach
Conclusions
• Risk-Risk assessment of available options
– Type/risk of lead failure
– Patient risk factors for lead failure & TLE
• Careful appraisal of operator experience
• Return all product regardless of TLE indication
• Be an active part of TLE community
Fineline®
Rescue
Fineline® Rescue