title: Mitral Stenosis and Aortic Atresia--A Risk Factor for Mortality After the Modified Norwood Operation in Hypoplastic Left Heart Syndrome.
abstract: BACKGROUND
  There are conflicting reports regarding the importance of mitral stenosis and aortic atresia as a risk factor for Norwood mortality. This study reviews outcomes of this anatomic subgroup at our institution and examines the utility of preoperative cardiac catheterization and its correlation with clinical outcomes and pathology findings.
  
  
  METHODS
  This is a single-center, retrospective review of hypoplastic left heart syndrome patients who underwent modified Norwood operation between October 2005 and May 2013.
  
  
  RESULTS
  Fourteen of 74 hypoplastic left heart syndrome patients (19%) had mitral stenosis and aortic atresia. Operative mortality for MS/AA was 29% versus 7% for all other hypoplastic left heart syndrome anatomic subgroups (p = 0.04). Although only 19% of the entire cohort, the mitral stenosis and aortic atresia subgroup constituted 50% of the total operative mortality and the only interstage deaths. Autopsies support myocardial ischemia as the mechanism of death. Although preoperative angiography defined the presence of ventriculo-coronary connections, it did not clearly risk stratify patients in regard to operative mortality.
  
  
  CONCLUSIONS
  Mitral stenosis and aortic atresia is a risk factor for perioperative myocardial ischemia and mortality. Further exploration of myocardial reserve is warranted.
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Stanford University School of Medicine, Palo Alto, California. Electronic address: ssiehr@stanford.edu.
authors.forename: Stephanie L
authors.initials: SL
authors.lastname: Siehr
authors.affiliation: Division of Pediatric Cardiac Surgery, Department of Cardiothoracic Surgery, Stanford University School of Medicine, Palo Alto, California.
authors.forename: Katsuhide
authors.initials: K
authors.lastname: Maeda
authors.affiliation: Department of Pathology, Stanford University School of Medicine, Palo Alto, California.
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Connolly
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Stanford University School of Medicine, Palo Alto, California.
authors.forename: Theresa A
authors.initials: TA
authors.lastname: Tacy
authors.affiliation: Division of Pediatric Cardiac Surgery, Department of Cardiothoracic Surgery, Stanford University School of Medicine, Palo Alto, California.
authors.forename: V Mohan
authors.initials: VM
authors.lastname: Reddy
authors.affiliation: Division of Pediatric Cardiac Surgery, Department of Cardiothoracic Surgery, Stanford University School of Medicine, Palo Alto, California.
authors.forename: Frank L
authors.initials: FL
authors.lastname: Hanley
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Stanford University School of Medicine, Palo Alto, California.
authors.forename: Stanton B
authors.initials: SB
authors.lastname: Perry
authors.affiliation: Division of Pediatric Cardiology, Department of Pediatrics, Stanford University School of Medicine, Palo Alto, California.
authors.forename: Gail E
authors.initials: GE
authors.lastname: Wright
mesh_terms: D000015:Abnormalities, Multiple; D001021:Aortic Valve / Q000002:abnormalities*; D000082882:Bicuspid Aortic Valve Disease; D002140:California / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006330:Heart Defects, Congenital / Q000401:mortality; D006349:Heart Valve Diseases / Q000151:congenital* / Q000401:mortality; D006801:Humans; D018636:Hypoplastic Left Heart Syndrome / Q000401:mortality / Q000601:surgery*; D007231:Infant, Newborn; D008297:Male; D008946:Mitral Valve Stenosis / Q000401:mortality*; D058327:Norwood Procedures; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends