Lute recovery of ventricular function in children with idiopathic dilated cardiomyopathy

Background The prognosis for children with idiopathic dilated cardiomyopath y (IDC) is variable. Patients who fail to exhibit improvement in left ventr icular (LV) function have a high 1-year mortality rate, whereas improvement in LV fractional shortening (LVFS] to >15% is associated with better survi val. However, complete recovery of LV performance to normal has not been ex amined. Methods and Results The clinical features and echocardiograms of 63 childre n with IDC were reviewed. Sixteen patients (group 1) were identified who de monstrated progressive improvement in LVFS, ultimately recovering to within the normal range. They were compared with 47 patients (group 2) in whom LV FS remained depressed. Group 1 LVFS at first examination was 13.6% +/- 5.1% , z = -10.8 +/- 4.0, and improved to within the normal range (33.7% +/- 3.4 %, z = -0.9 +/- 1.4, P <.001). Group 2 initial LVFS was 13.6 +/- 2.3, z = - 8.9 +/- 3.2 and did not change significantly (15.7% +/- 73%, z = -7.3 +/- 1 .6). The LV was dilated at initial examination in all patients (z = 6.9 +/- 3.0). Recovery in group 1 was associated with a decrease in IV dimension t o within the normal range (z = 1.3 +/- 1.6, P <.001), whereas the LV dimens ion in group 2 patients remained increased (z = 6.2 +/- 3.4). The mean foll ow-up time at which LV function was noted to be normal was 4.5 +/- 3.6 year s (range 0.3 to 14 years). The total duration of follow-up was 6.5 +/- 5.2 years (range 1 to 16 years), Conclusions Complete recovery of LV function is possible in children with I DC. Recovery may occur within the first year oiler initial examination in s ome patients, but longer periods ore needed in the majority of patients in whom LV function ultimately returned to normal.