Long term somatic growth after repair of tetralogy of Fallot: evidence for restoration of genetic growth potential

Objective: To compare actual with predicted long term growth after early repair of tetralogy of Fallot (TOF). Design: Serial preoperative and postoperative anthropometric data were converted with z scores. The presence of restrictive physiology was assessed by echocardiography. Patients: 45 otherwise healthy patients who underwent repair at median age 1.6 years ( range 0.2 - 4.9) were studied. Predicted height was determined from mid-parental height corrected for sex. Results: Mean (SD) weight and height z scores at the time of surgery were significantly depressed (-1.04 (0.82) and -0.93 (0.95), respectively; p< 0.0001 for both). At latest follow up at a median age of 14.2 years (range 11 - 20.5), mean weight and height z scores were 0.16 (1.1) and -0.05 (0.81) ( p = 0.32 and p = 0.41, respectively). The improvement between surgical and late weight and height z scores was significant ( p, 0.0001 for each comparison). Catch up growth was largely complete within two years. Age at correction, duration of follow up, and prior surgical procedures were unrelated to growth. Mean current height z scores were similar to those predicted by mid-parental height. Patients with restrictive right ventricular physiology (n = 24) had a significantly greater late z score for weight (0.49 v -0.34; p = 0.01), with a similar trend for height. Low birth weight patients experienced comparable catch up growth but remained shorter than patients with normal birth weight ( mean height z score -0.64 v 0.06; p = 0.03). Conclusions: Early repair of TOF results in significant acceleration of weight and height, with normalisation of long term growth and fulfilment of genetic growth potential.