Heterotaxy syndrome and malrotation: does isomerism influence risk and decision to treat.

Purpose: Controversy remains regarding the management of the asymptomatic heterotaxy syndrome (HS) patient with suspected intestinal rotational abnormalities. We evaluated the outcomes for our HS population to identify frequency of malrotation and identify characteristics of children who might benefit from expectant management.

Methods: After IRB approval, a retrospective review of all patients treated for HS at a large tertiary care children's hospital between January 2008 and June 2012 was performed. For the purpose of this paper, malrotation was defined as an operative note that described the presence of Ladd's bands and a narrow mesentery.

Results: Thirty-eight patients with HS were identified, including 18 who underwent abdominal exploration. Left atrial isomerisation (LAI) was identified in 13 individuals, and right atrial isomerisation (RAI) was noted in 25. The rate of surgical intervention did not vary between the 2 groups (54%). Malrotation was found in 8 patients: one with LAI and 7 with RAI. This difference in incidence was statistically significant (p=0.04).

Conclusion: These data suggest that the direction of atrial isomerisation influences the likelihood of true malrotation, where RAI patients are more likely to be malrotated. Given the inherent risk of surgery on this medically fragile patient population, surgeons should consider expectant management for asymptomatic LAI patients.