MRI LA Size

Buzz

  • Overall volume
    • RV volume is <2/3 the volume of LV
    • LA and RA are about 1/3 volume of the RV and LV
    • Peak systole volume in LV and RV should = 1/3 of diastolic volume
  • Shapes
    • LA rectangular with flat back
    • RA flat back
    • LV Ovoid with icecream cone shaped cavity
    • RV triangular shaped and septum bulges into it (“punch in the belly”
  • Linear Size
    • LA +/- 4cms (post wall to MV)
    • LV +/-  5cms (transverse) not >6
    • RV +/- 4cms (transverse) not >6
    • RA +/- 5cms (post wall to TV)
  • Wall thickness
    • Measure in diastole
      • LV 1.2 to 1.4cms
      • RV 3-5mms
NORMAL MRI 4 CHAMBERED VIEW
This is the MRI of a 19 year old male who presented with syncope and the study was performed to identify a possible arrhythmogenic focus
White blood imaging using 4 chamber view shows a normal sized heart in systole (above) and diastole below. The left and right atria have flattened surfaces, and occupy about 1/3 the volume of the ventricles. Note in diastole the MV and TV are open
Ashley Davidoff MD
NORMAL MRI 4 CHAMBERED VIEW WITH MEASUREMENTS
White blood imaging using 4 chamber view shows a normal sized heart in systole (above) and diastole (below). The left ad right atria have flattened surfaces, and occupy about 1/3 the volume of the ventricles. The A-P dimension of the LA during diastole is about 4cms (normal) and the RA is about 5cms (normal). The RV volume is about 2/3 the volume of the LV. The transverse dimension of the RV in diastole is about 4cms and the LV 5cms – both normal. The septum of the LV in diastole (lower image) is less than 9mm, and the free wall is 9mms (upper limits normal is 1.2 cms. The wall of the RV is barely seen and is in the range of about 3 mm. Note in diastole the MV and TV are open. The difference in diameter of the RV in systole and diastole is about 2/3 and similarly of the LV. This an approximately normal ratio
Ashley Davidoff MD
NORMAL MRI OF THE LEFT ATRIUM in the AXIAL VIEW WITH MEASUREMENTS
White blood imaging of the LA in the axial projection shows a normal sized LA measuring 1.7cms (normal up to 4cms). In this plane the LA is relatively small, but normal. It is usually slightly larger than the proximal ascending aorta at this level. The aorta measures 2.3cms. Note the rectangular shape of the LA.
Ashley Davidoff MD