title: Eligibility for the Subcutaneous Implantable Cardioverter-Defibrillator in Patients With Hypertrophic Cardiomyopathy.
abstract: BACKGROUND
  High-risk hypertrophic cardiomyopathy (HCM) patients benefit from the implantable cardioverter defibrillator (ICD). The subcutaneous ICD (S-ICD) may provide comparable protection while avoiding the shortcomings of transvenous (TV) leads. We assessed S-ICD eligibility according to surface ECG screening test in a cohort of high-risk HCM patients.
  
  
  RESULTS
  47 HCM patients (3 S-ICD candidates; 41 TV-ICD patients without pacing indication; and 3 pacemaker-dependent TV-ICD patients) underwent 4 screening protocols: standard (n = 44); exercise (n = 33); continuous pacing (n = 44); alternating paced/spontaneous QRS (n = 41). Of the 44 patients in the standard screening group, 41 (93%) were eligible. Max LV thickness was inversely related to the number of qualifying leads (3 leads: 21 ± 4 mm; 2 leads: 22 ± 6 mm; 1 lead: 25 ± 6 mm; no leads: 28 ± 11 mm; P = 0.07). Of the 33 patients in the exercise group, 5 were ineligible (3 after exercise). Of these, 2 became eligible after moving sternal electrodes from the left to the right parasternal line (eligibility rate: 30/33; 91%). Of the 44 patients in the continuous pacing group, 28 (64%) were eligible, 8 of which with right parasternal electrodes. In the paced/spontaneous QRS group (n = 41), 21 patients (51%) had at least 1 eligible lead during pacing and retained compatibility on the same lead during spontaneous rhythm, 5 of which with right parasternal electrodes.
  
  
  CONCLUSIONS
  S-ICD screening failure is low in HCM, provided that patients with severe hypertrophy are carefully evaluated. Exercise test should be performed and right parasternal leads tested. Pacemaker patients display lower eligibility rate.
authors.affiliation: Division of Cardiology, Department of Clinical and Molecular Medicine, St. Andrea Hospital, Sapienza University, Rome, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Francia
authors.affiliation: Division of Cardiology, Department of Clinical and Molecular Medicine, St. Andrea Hospital, Sapienza University, Rome, Italy.
authors.forename: Carmen
authors.initials: C
authors.lastname: Adduci
authors.affiliation: Division of Cardiology, Department of Clinical and Molecular Medicine, St. Andrea Hospital, Sapienza University, Rome, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Palano
authors.affiliation: Division of Cardiology, Department of Clinical and Molecular Medicine, St. Andrea Hospital, Sapienza University, Rome, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Semprini
authors.affiliation: Division of Cardiology, Department of Clinical and Molecular Medicine, St. Andrea Hospital, Sapienza University, Rome, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Serdoz
authors.affiliation: Division of Cardiology, Department of Clinical and Molecular Medicine, St. Andrea Hospital, Sapienza University, Rome, Italy.
authors.forename: Dalma
authors.initials: D
authors.lastname: Montesanti
authors.affiliation: Division of Cardiology, Department of Clinical and Molecular Medicine, St. Andrea Hospital, Sapienza University, Rome, Italy.
authors.forename: Daria
authors.initials: D
authors.lastname: Santini
authors.affiliation: Division of Cardiology, Department of Clinical and Molecular Medicine, St. Andrea Hospital, Sapienza University, Rome, Italy.
authors.forename: Beatrice
authors.initials: B
authors.lastname: Musumeci
authors.affiliation: Division of Cardiology, Department of Clinical and Molecular Medicine, St. Andrea Hospital, Sapienza University, Rome, Italy.
authors.forename: Adriano
authors.initials: A
authors.lastname: Salvati
authors.affiliation: Division of Cardiology, Department of Clinical and Molecular Medicine, St. Andrea Hospital, Sapienza University, Rome, Italy.|IRCCS Neuromed, Pozzilli, Isernia, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Volpe
authors.affiliation: Division of Cardiology, Department of Clinical and Molecular Medicine, St. Andrea Hospital, Sapienza University, Rome, Italy.
authors.forename: Camillo
authors.initials: C
authors.lastname: Autore
mesh_terms: D000328:Adult; D000368:Aged; D002304:Cardiac Pacing, Artificial; D002312:Cardiomyopathy, Hypertrophic / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D016757:Death, Sudden, Cardiac / Q000209:etiology / Q000517:prevention & control*; D017147:Defibrillators, Implantable; D004554:Electric Countershock / Q000295:instrumentation*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D004608:Eligibility Determination; D005080:Exercise Test; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011237:Predictive Value of Tests; D011474:Prosthesis Design; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*; D014693:Ventricular Fibrillation / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology / Q000628:therapy*
keywords: hypertrophic cardiomyopathy; implantable cardioverter defibrillator; subcutaneous ICD, sudden death; transvenous ICD