Acute Lead Dislodgements in NCDR® ICD Registry™ Patients

Alan Cheng, MD, Yongfei Wang, MS, Jeptha P. Curtis, MD, Paul D. Varosy, MD

Johns Hopkins University School of MedicineYale University School of Medicine

University of Colorado, Denver School of MedicineNovember 16, 2009

Disclosures• A.C.

– Boston Scientific (research, honorarium)

– Medtronic (honorarium)

• J.P.C.

– Medtronic (ownership)

• P.D.V.

– Boston Scientific (honorarium)

Background• Acute lead dislodgements are common

adverse events

• Current estimates range between 1.8-8%

• Many dislodgements occur early after implant

• Little is known regarding predisposing factors and sequelae related to lead dislodgments

Methods• NCDR® ICD Registry™ includes Medicaire

beneficiaries undergoing ICD/CRT implants

• Entries from 4/2006—09/2008 screened

• Previous ICDs excluded

• 1° endpoint: acute lead dislodgements

• 2° endpoint: advanced adverse events

Methods (cont’d)• Variables used in ICD Registry™ v1.08

• X2 and t testing

• Hierarchical logistic regression models generated

• P<0.05 considered significant

• Missing data <0.5%. Dummy variables imputed to avoid case-wise deletion

Results

• 226,764 were used in the analysis

– 35.2% analyzed were CRT-D systems

• Acute lead dislodgements occurred with a frequency of 1.1%

Results: Entire CohortAge 67.5 years

Females 27%

Non White 23.7%

Ischemic 65.2%

Diabetes 37.2%

Hypertension 75.2%

ESRD 4.2%

Variable Acute Dislodgement No Acute Dislodgement P Value

Age 68.5 ± 12.7 yrs 67.5 ± 13 yrs 0.0002

Female 29.9% 27.0% <0.002

NYHA Class <0.0001

Class I 9.3% 12.4%

Class II 26.3% 35.8%

Class III 58.1% 47.4%

Class IV 6.5% 4.4%

Variable Acute Dislodgement No Dislodgement P Value

Atrial fibrillation 35.9% 31.3% <0.0001

Ischemic CM 60.3% 65.3% <0.0001

Prior pacemaker 14.1% 11.2% <0.0001

CVA 16.7% 14.5% 0.0016

Lung disease 25.6% 22.8% 0.0007

Variable Acute Dislodgement No Dislodgement P Value

Ejection fraction 26.8 ± 10.5% 27.5 ± 10.7% 0.0026

QRS Duration 134.6 ± 35msec 125.3 ± 34msec <0.0001

Biventricular 54.6% 35.0% <0.0001

Epicardial lead 7.4% 3.8% <0.0001

Variable Dislodgements No Dislodgements P Value

Implant Volume 135 ± 97 144 ± 101 <0.0001

Teaching Hospital 55.2% 54.7% 0.65

Physician Training 0.007

BC/BE EP 80.9% 82.3%

HRS Guidelines 11.2% 9.7%

Surgery Boards 2.8% 2.0%

Variable Acute Dislodgements No Dislodgements P Value

Length of Stay 6.02 days 4.51 days <0.002

Drug Reaction 0.32% 0.09% <0.0001

Sup. Phlebitis 0.16% 0.04% <0.004

Hematoma 4.38% 0.97% <0.0001

Infection 0.16% 0.03% <0.0001

Peri. embolus 0.20% 0.03% <0.0001

Variable Acute Dislodgements No Dislodgements P Value

Cardiac Arrest 1.10% 0.31% <0.0001

Cardiac Perforation

0.89% 0.07% <0.0001

Pneumothorax 1.38% 0.48% <0.0001

Hemothorax 0.24% 0.09% 0.0171

In hospital death 1.05% 0.41% <0.0001

Endpoint Odds Ratio* Confidence Intervals

Combined Events 3.4 2.8—4.2(Cardiac arrest, Cardiac

Perforation, Pneumothorax, Cardiac Tamponade,

Infection)

In hospital Death 2.1 1.5—2.9

*Adjusted for age, gender, race, CHF, atrial fibrillation, cardiomyopathy etiology, CVA, lung disease, renal failure, ejection fraction, QRS duration, physician implant volume, hospital volume

*Adjusted for age, gender, race, CHF, atrial fibrillation, cardiomyopathy etiology, CVA, lung disease, renal failure, ejection fraction, QRS duration, physician implant volume, hospital volume

Conclusions

• Acute lead dislodgements—most common adverse events (1.1%)

• Individuals with greater comorbidities at greater risk

• Formalized EP training associated with fewer events

Conclusions (cont’d)

• Downstream adverse events occur 10.9%

• Lead dislodgments increase risk for major complications and in hospital death after adjustment for confounders