title: Intraventricular dyssynchrony in light chain amyloidosis: a new mechanism of systolic dysfunction assessed by 3-dimensional echocardiography.
abstract: BACKGROUND
  Light chain amyloidosis (AL) is a rare but often fatal disease due to intractable heart failure. Amyloid deposition leads to diastolic dysfunction and often preserved ejection fraction. We hypothesize that AL is associated with regional systolic dyssynchrony. The aim is to compare left ventricular (LV) regional synchrony in AL subjects versus healthy controls using 16-segment dyssynchrony index measured from 3-dimension-al (3D) echocardiography.
  
  
  METHODS
  Cardiac 3D echocardiography full volumes were acquired in 10 biopsy-proven AL subjects (60 +/- 3 years, 5 females) and 10 healthy controls (52 +/- 1 years, 5 females). The LV was subdivided into 16 segments and the time from end-diastole to the minimal systolic volume for each of the 16 segments was expressed as a percent of the cycle length. The standard deviations of these times provided a 16-segment dyssynchrony index (16-SD%). 16-SD% was compared between healthy and AL subjects.
  
  
  RESULTS
  Left ventricular ejection fraction was comparable (control vs. AL: 62.4 +/- 0.6 vs. 58.6 +/- 2.8%, p = NS). 16-SD% was significantly higher in AL versus healthy subjects (5.93 +/- 4.4 vs. 1.67 +/- 0.87%, p = 0.003). 16-SD% correlated with left ventricular mass index (R 0.45, p = 0.04) but not to left ventricular ejection fraction.
  
  
  CONCLUSIONS
  Light chain amyloidosis is associated with left ventricular regional systolic dyssynchrony. Regional dyssynchrony may be an unrecognized mechanism of heart failure in AL subjects.
authors.affiliation: Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, USA. rmigrino@mcw.edu
authors.forename: Raymond Q
authors.initials: RQ
authors.lastname: Migrino
authors.forename: Leanne
authors.initials: L
authors.lastname: Harmann
authors.forename: Timothy
authors.initials: T
authors.lastname: Woods
authors.forename: Megan
authors.initials: M
authors.lastname: Bright
authors.forename: Seth
authors.initials: S
authors.lastname: Truran
authors.forename: Parameswaran
authors.initials: P
authors.lastname: Hari
mesh_terms: D000686:Amyloidosis / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D009202:Cardiomyopathies / Q000000981:diagnostic imaging* / Q000503:physiopathology; D019560:Echocardiography, Three-Dimensional; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume; D013599:Systole; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology