title: Changes in left atrial deformation in hypertrophic cardiomyopathy: Evaluation by vector velocity imaging.
abstract: OBJECTIVE
  Hypertrophic cardiomyopathy (HCM) represents a generalized myopathic process affecting both ventricular and atrial myocardium. We assessed the global and regional left atrial (LA) function and its relation to left ventricular (LV) mechanics and clinical status in patients with HCM using Vector Velocity Imaging (VVI).
  
  
  METHODS
  VVI of the LA and LV was acquired from apical four- and two-chamber views of 108 HCM patients (age 40 ± 19years, 56.5% men) and 33 healthy subjects, all had normal LV systolic function. The LA subendocardium was traced to obtain atrial volumes, ejection fraction, velocities, and strain (ϵ)/strain rate (SR) measurements.
  
  
  RESULTS
  Left atrial reservoir (ϵsys,SRsys) and conduit (early diastolic SRe) function were significantly reduced in HCM compared to controls (P < .0001). Left atrial deformation directly correlated to LVϵsys, SRsys and negatively correlated to age, NYHA class, left ventricular outflow tract (LVOT) gradient, left ventricular mass index (LVMI), LA volume index and severity of mitral regurge (P < 0.001). Receiver operating characterist was constructed to explore the cutoff value of LA deformation in differentiation of LA dysfunction; ϵsys < 40% was 75% sensitive, 50% specific, SRsys < 1.7s(- 1) was 70% sensitive, 61% specific, SRe> - 1.8s(- 1) was 81% sensitive and 30% specific, SRa> - 1.5s(- 1) was 73% sensitive and 40% specific. By multivariate analysis global LVϵsys and LV septal thickness are independent predictors for LAϵsys, while end systolic diameter is the only independent predictor for SRsys, P < .001.
  
  
  CONCLUSIONS
  Left atrial reservoir and conduit function as measured by VVI were significantly impaired while contractile function was preserved among HCM patients. Left atrial deformation was greatly influenced by LV mechanics and correlated to severity of phenotype.
authors.forename: Hala Mahfouz
authors.initials: HM
authors.lastname: Badran
authors.affiliation: Cardiology Department, Menoufiya University, Egypt.
authors.forename: Ghada
authors.initials: G
authors.lastname: Soltan
authors.affiliation: Cardiology Department, Menoufiya University, Egypt.
authors.forename: Hesham
authors.initials: H
authors.lastname: Hassan
authors.affiliation: Cardiology Department, Menoufiya University, Egypt.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Nazmy
authors.forename: Naglaa
authors.initials: N
authors.lastname: Faheem
authors.affiliation: Cardiology Department, Menoufiya University, Egypt.
authors.forename: Haythem
authors.initials: H
authors.lastname: Saadan
authors.forename: Magdi H
authors.initials: MH
authors.lastname: Yacoub
keywords: hypertrophic cardiomyopathy; left atrial deformation; vector velocity imaging