No abstract

BackgroundFibrosis after myocardial damage can be determined by cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE). We studied whether ventricular LGE is visible in the ventricles of pediatric and adolescent TOF (tetralogy of Fallot) patients by measuring LGE and investigating whether fibrosis correlated with right ventricular volume, pulmonary regurgitation, N-terminal pro-brain natriuretic peptide (NT-proBNP) or the aminoterminal propeptide of type III procollagen (PIIINP). We also studied if the patient's age, post-operative follow-up time or surgical history would affect LGE.MethodsA total of 40 pediatric patients who had undergone TOF repair and 43 healthy age and gender matched controls underwent a CMR study, whereby LGE was scored in the right (RV) and the left ventricle. To exclude the possible iatrogenic scarring we calculated the LGE score by excluding the right ventricular outflow tract and VSD patch region.ResultsAll patients had RV LGE and in 39 of 40 it was seen also outside the surgically affected areas. The amount of LGE correlated positively with the RV end-diastolic volume (r = 0.44, P = 0.0045), pulmonary regurgitation (r = 0.40, P = 0.013), and with NT-proBNP. The presence of LGE also depended on post-operative follow-up time (r = 0.53, P = 0.006). PIIINP levels of TOF patients were significantly higher than in the control subjects but it did not correlate with LGE or with any of the studied clinical markers.ConclusionsLGE is present globally in the right ventricular muscle in children and adolescents with TOF. The longer the follow-up time the more common was the LGE in the right ventricle.

In patients with tetralogy of Fallot, severe pulmonary regurgitation has a significant effect on volume flow through the left atrium. Reduction in left ventricular preload volume may be an additional factor contributing to left ventricular dysfunction.