title: Septal Ablation and Hypertrophic Obstructive Cardiomyopathy: 7 Years US Experience.
abstract: BACKGROUND
  Septal ablation (SA) is a key modality for left ventricular outflow tract gradient reduction in hypertrophic obstructive cardiomyopathy (HOCM) patients with refractory symptoms. The primary objective of our study was to evaluate post-procedural mortality, complications, length of stay (LOS), and cost of hospitalization following SA.
  
  
  METHODS
  We queried the Nationwide Inpatient Sample (NIS) between 2005 and 2011 using the ICD9 procedure code of 37.34 for ablation of heart tissue. Only adult patients with HOCM (ICD-9-CM: 425.1) were included. Patients with any arrhythmia diagnosis or open surgical ablation procedure code were excluded. Hierarchical mixed effects models were generated in order to identify the independent multivariate predictors of outcomes.
  
  
  RESULTS
  A total of 358 SAs were available for analysis. There was no reported mortality during the study period; permanent pacemaker implantation rate was 8.7%. Highest hospital volume tertile (OR, 95%CI, P- value) predicted significantly lower post-procedural complications (0.51, 0.26-0.98, P = 0.04). Univariate analysis of highest versus lowest tertile of hospital volume showed significant decrease in LOS (2.6 days vs. 3.8 days, P<0.01) and non-significant decrease hospitalization costs (16,800$ vs. 19,500$, P = 0.29).
  
  
  CONCLUSIONS
  SA is a safe procedure and associated with low peri- procedural mortality rate. A higher burden of baseline comorbidities is associated with worse outcomes while higher annual hospital volume is associated with lower rate of post-procedural complications, length of stay, and cost of care following SA.
authors.affiliation: Mount Sinai St. Luke's Roosevelt Hospital, New York, New York.
authors.forename: Ankit
authors.initials: A
authors.lastname: Chothani
authors.affiliation: Borgess Medical Institute, Kalamazoo, Michigan.
authors.forename: Sidakpal S
authors.initials: SS
authors.lastname: Panaich
authors.affiliation: Saint Peter's University Hospital, New Brunswick, New Jersey.
authors.forename: Nilay
authors.initials: N
authors.lastname: Patel
authors.affiliation: University of Miami Miller School of Medicine, Miami, Florida.
authors.forename: Nileshkumar J
authors.initials: NJ
authors.lastname: Patel
authors.affiliation: Mount Sinai St. Luke's Roosevelt Hospital, New York, New York.
authors.forename: Shilpkumar
authors.initials: S
authors.lastname: Arora
authors.affiliation: Mayo Clinic, Rochester, Minnesota.
authors.forename: Abhishek
authors.initials: A
authors.lastname: Deshmukh
authors.affiliation: Detroit Medical Center, Detroit, Michigan.
authors.forename: Cindy
authors.initials: C
authors.lastname: Grines
authors.affiliation: The Everett Clinic, Everett, Washington. abadheka@everettclinic.com.
authors.forename: Apurva O
authors.initials: AO
authors.lastname: Badheka
mesh_terms: D000328:Adult; D000368:Aged; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000601:surgery; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods; D005260:Female; D006346:Heart Septum / Q000000981:diagnostic imaging / Q000601:surgery; D006760:Hospitalization / Q000191:economics; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D010043:Outcome and Process Assessment, Health Care; D011183:Postoperative Complications / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology; D014694:Ventricular Outflow Obstruction / Q000209:etiology / Q000601:surgery