title: Hemodynamic changes in systolic and diastolic function during isoproterenol challenge predicts symptomatic response to myectomy in hypertrophic cardiomyopathy with labile obstruction.
abstract: OBJECTIVE
  We aimed to assess the utility of changes in systolic and diastolic function by isoproterenol challenge in predicting symptom resolution post-myectomy in selected patients with hypertrophic cardiomyopathy (HCM) and labile obstruction.
  
  
  BACKGROUND
  In a subset of symptomatic HCM patients without resting/provocable obstruction on noninvasive assessment, isoproterenol challenge during hemodynamic catheterization may elicit labile left ventricular outflow tract (LVOT) obstruction, and demonstrate the effect of obstruction on diastolic function. These changes may determine whether patients achieve complete symptom resolution post-myectomy.
  
  
  METHODS
  Between February 2003 and April 2009, 18 symptomatic HCM patients without LVOT obstruction on noninvasive testing underwent isoproterenol provocation and septal myectomy due to presence of provocable gradient and were followed for 4 (IQR 3-7) years.
  
  
  RESULTS
  Thirteen (72.2%) had complete symptom resolution, while 5 (27.8%) had improved, but persistent symptoms. Those with provoked gradient >100 mm Hg or increase in left atrial pressure (LAP) with isoproterenol had symptom resolution.
  
  
  CONCLUSIONS
  Symptomatic HCM patients without LVOT gradient on noninvasive testing may demonstrate labile obstruction with isoproterenol. With isoproterenol, patients with high LVOT gradient or increase in LAP concomitant with an increase in gradient achieved complete symptom resolution post-myectomy. Thus, improved diastolic filling as well as outflow gradient production in patients with HCM may predict symptom response to myectomy. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
authors.forename: Megha
authors.initials: M
authors.lastname: Prasad
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
authors.forename: Jeffrey B
authors.initials: JB
authors.lastname: Geske
authors.affiliation: Minneapolis Heart Institute, Minneapolis, Minnesota.
authors.forename: Paul
authors.initials: P
authors.lastname: Sorajja
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
authors.forename: Steve R
authors.initials: SR
authors.lastname: Ommen
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
authors.forename: Hartzell V
authors.initials: HV
authors.lastname: Schaff
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
authors.forename: Bernard J
authors.initials: BJ
authors.lastname: Gersh
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota.
authors.forename: Rick A
authors.initials: RA
authors.lastname: Nishimura
mesh_terms: D000368:Aged; D006348:Cardiac Surgical Procedures / Q000379:methods*; D002312:Cardiomyopathy, Hypertrophic / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D002316:Cardiotonic Agents / Q000627:therapeutic use; D003971:Diastole; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006346:Heart Septum / Q000000981:diagnostic imaging / Q000601:surgery*; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D007545:Isoproterenol / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014694:Ventricular Outflow Obstruction / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy
chemical_list: D002316:Cardiotonic Agents; D007545:Isoproterenol
keywords: diastolic dysfunction; hypertrophic cardiomyopathy; isoproterenol; myectomy