title: Healthcare Utilization and Expenditures Associated With Appropriate and Inappropriate Implantable Defibrillator Shocks.
abstract: In patients with implantable cardioverter-defibrillators, healthcare utilization (HCU) and expenditures related to shocks have not been quantified.
  
  
  
  We performed a retrospective cohort study of patients with implantable cardioverter-defibrillators identified from commercial and Medicare supplemental claims databases linked to adjudicated shock events from remote monitoring data. A shock event was defined as ≥1 spontaneous shocks delivered by an implanted device. Shock-related HCU was ascertained from inpatient and outpatient claims within 7 days following a shock event. Shock events were adjudicated and classified as inappropriate or appropriate, and HCU and expenditures, stratified by shock type, were quantified. Of 10 266 linked patients, 963 (9.4%) patients (61.3±13.6 years; 81% male) had 1885 shock events (56% appropriate, 38% inappropriate, and 6% indeterminate). Of these events, 867 (46%) had shock-related HCU (14% inpatient and 32% outpatient). After shocks, inpatient cardiovascular procedures were common, including echocardiography (59%), electrophysiology study or ablation (34%), stress testing (16%), and lead revision (11%). Cardiac catheterization was common (71% and 51%), but percutaneous coronary intervention was low (6.5% and 5.0%) after appropriate and inappropriate shocks. Expenditures related to appropriate and inappropriate shocks were not significantly different.
  
  
  
  After implantable cardioverter-defibrillator shock, related HCU was common, with 1 in 3 shock events followed by outpatient HCU and 1 in 7 followed by hospitalization. Use of invasive cardiovascular procedures was substantial, even after inappropriate shocks, which comprised 38% of all shocks. Implantable cardioverter-defibrillator shocks seem to trigger a cascade of health care. Strategies to reduce shocks could result in cost savings.
authors.affiliation: From the Center for Digital Health, Stanford University School of Medicine, Stanford, CA (M.P.T.); the Division of Cardiac Electrophysiology, Hartford Healthcare Heart and Vascular Institute, Hartford, CT (S.Z.); the Department of Economics, Reimbursement, and Evidence, Medtronic plc, Mounds View, MN (A.L.S., S.A.M.); and Baim Institute for Clinical Research, Boston, MA (M.R.R.). mintu@stanford.edu.
authors.forename: Mintu P
authors.initials: MP
authors.lastname: Turakhia
authors.affiliation: From the Center for Digital Health, Stanford University School of Medicine, Stanford, CA (M.P.T.); the Division of Cardiac Electrophysiology, Hartford Healthcare Heart and Vascular Institute, Hartford, CT (S.Z.); the Department of Economics, Reimbursement, and Evidence, Medtronic plc, Mounds View, MN (A.L.S., S.A.M.); and Baim Institute for Clinical Research, Boston, MA (M.R.R.).
authors.forename: Steven
authors.initials: S
authors.lastname: Zweibel
authors.affiliation: From the Center for Digital Health, Stanford University School of Medicine, Stanford, CA (M.P.T.); the Division of Cardiac Electrophysiology, Hartford Healthcare Heart and Vascular Institute, Hartford, CT (S.Z.); the Department of Economics, Reimbursement, and Evidence, Medtronic plc, Mounds View, MN (A.L.S., S.A.M.); and Baim Institute for Clinical Research, Boston, MA (M.R.R.).
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Swain
authors.affiliation: From the Center for Digital Health, Stanford University School of Medicine, Stanford, CA (M.P.T.); the Division of Cardiac Electrophysiology, Hartford Healthcare Heart and Vascular Institute, Hartford, CT (S.Z.); the Department of Economics, Reimbursement, and Evidence, Medtronic plc, Mounds View, MN (A.L.S., S.A.M.); and Baim Institute for Clinical Research, Boston, MA (M.R.R.).
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Mollenkopf
authors.affiliation: From the Center for Digital Health, Stanford University School of Medicine, Stanford, CA (M.P.T.); the Division of Cardiac Electrophysiology, Hartford Healthcare Heart and Vascular Institute, Hartford, CT (S.Z.); the Department of Economics, Reimbursement, and Evidence, Medtronic plc, Mounds View, MN (A.L.S., S.A.M.); and Baim Institute for Clinical Research, Boston, MA (M.R.R.).
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Reynolds
mesh_terms: D000067575:Administrative Claims, Healthcare / Q000191:economics; D000368:Aged; D000553:Ambulatory Care / Q000191:economics; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000191:economics* / Q000628:therapy*; D016208:Databases, Factual; D017147:Defibrillators, Implantable / Q000009:adverse effects / Q000191:economics* / Q000706:statistics & numerical data; D004554:Electric Countershock / Q000009:adverse effects / Q000191:economics* / Q000295:instrumentation / Q000706:statistics & numerical data; D004868:Equipment Failure / Q000191:economics*; D005260:Female; D017048:Health Care Costs; D005102:Health Expenditures; D006295:Health Resources / Q000191:economics* / Q000706:statistics & numerical data; D017721:Hospital Costs; D006801:Humans; D008297:Male; D016345:Medicare Part B / Q000191:economics; D008875:Middle Aged; D010343:Patient Admission / Q000191:economics; D017064:Process Assessment, Health Care / Q000191:economics*; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States; D019564:Unnecessary Procedures / Q000191:economics
keywords: cardiac arrhythmias; defibrillators; electrophysiology; hospitalization