Abnormal cardiac inflow patterns during postnatal development in a mouse model of Holt-Oram syndrome

Am J Physiol Heart Circ Physiol. 2005 Sep;289(3):H992-H1001. doi: 10.1152/ajpheart.00027.2005. Epub 2005 Apr 22.


Tbx5(del/+) mice provide a model of human Holt-Oram syndrome. In this study, the cardiac functional phenotypes of this mouse model were investigated with 30-MHz ultrasound by comparing 12 Tbx5(del/+) mice with 12 wild-type littermates at 1, 2, 4, and 8 wk of age. Cardiac dimensions were measured with two-dimensional and M-mode imaging. The flow patterns in the left and right ventricular inflow channels were evaluated with Doppler flow sampling. Compared with wild-type littermates, Tbx5(del/+) mice showed significant changes in the mitral flow pattern, including decreased peak velocity of the left ventricular (LV) early filling wave (E wave), increased peak velocity of the late filling wave (A wave), and decreased or even reversed peak E-to-A ratio. The prolongation of LV isovolumic relaxation time was detected in Tbx5(del/+) neonates as early as 1 wk of age. In Tbx5(del/+) mice, LV wall thickness appeared normal but LV chamber dimension was significantly reduced. LV systolic function did not differ from that in wild-type littermates. In contrast, the Doppler flow spectrum in the enlarged tricuspid orifice of Tbx5(del/+) mice demonstrated increased peak velocities of both E and A waves and increased total time-velocity integral but unchanged peak E/A. In another 13 mice (7 Tbx5(del/+), 6 wild-type) at 2 wk of age, significant correlation was found between Tbx5 gene expression level in ventricular myocardium and LV filling parameters. In conclusion, the LV diastolic function of Tbx5(del/+) mice is significantly deteriorated, whereas the systolic function remains normal.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Diastole
  • Disease Models, Animal*
  • Echocardiography
  • Female
  • Heart / growth & development
  • Heart / physiopathology
  • Heart Defects, Congenital / diagnostic imaging
  • Heart Defects, Congenital / genetics
  • Heart Defects, Congenital / physiopathology*
  • Heart Septal Defects, Atrial / diagnostic imaging
  • Heart Septal Defects, Atrial / genetics
  • Heart Septal Defects, Atrial / physiopathology*
  • Male
  • Mice
  • Mice, Mutant Strains*
  • Phenotype
  • Systole
  • T-Box Domain Proteins / genetics*
  • Ventricular Dysfunction, Left / diagnostic imaging
  • Ventricular Dysfunction, Left / genetics
  • Ventricular Dysfunction, Left / physiopathology
  • Ventricular Dysfunction, Right / diagnostic imaging
  • Ventricular Dysfunction, Right / genetics
  • Ventricular Dysfunction, Right / physiopathology


  • T-Box Domain Proteins
  • T-box transcription factor 5