Changes in left ventricular mass with rejection after heart transplantation in infants.

Thirty-three infants who underwent successful heart transplantation before 6 months of age were studied to evaluate subacute changes in left ventricular mass (LVM) and its correlation to a history of rejection episodes. LVM and left ventricular wall mass (LVWM) and their percentage of predicted normal values were analyzed by means of M-mode echocardiography. LVM (as a percentage of predicted normal for body surface area) at 1 week, 1 month, and 3 months after transplantation was 103.2% +/- 24.5%, 137.3% +/- 36.0%, and 138.6% +/- 32.0%, respectively. Values for the wall mass were 82.1% +/- 23.0%, 111.3% +/- 35.7%, and 104.6% +/- 30.4%. After 1 and 3 months, both LVM and LVWM were significantly (p less than 0.01) increased from the values in the first week. The patients were subdivided on the basis of a history of rejection. There were six patients without a rejection episode within 1 month (group 1), 17 patients with one rejection episode (group 2), and 10 patients with two or more episodes (group 3). LVM at 1 month was 104.5% +/- 27.7% for group 1, 142.5% +/- 27.7% for group 2 (p less than 0.05), and 148.9% +/- 31.3% for group 3 (p less than 0.05). LVWM at 1 month was 83.4% +/- 24.6%, 114.8% +/- 35.3%, and 122.2% +/- 36.2% (groups 1 through 3, respectively). Thus an increase in posttransplant LVM may signify a rejection episode. Heart transplantation in infancy increases LVM and LVWM (septum and posterior wall); the degree of thickening of septum correlates well with rejection episodes.