Late gadolinium enhancement (LGE) progresses with right ventricle volume in children after repair of tetralogy of fallot

Abstract

Background: Fibrosis 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.

Methods: A 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.

Results: All 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.

Conclusions: LGE 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.

Keywords: Cardiac magnetic resonance; Late gadolinium enhancement; Pediatric cardiology; Pulmonary regurgitation; Right ventricular volume; Tetralogy of Fallot.

Fig. 1

Five-step segmental late gadolinium enhancement (LGE) grading protocol: in the first three segments measuring right ventricular (RV) free wall and the interventricular septum the scoring was done as follows: 0 points = no enhancement, 1 point < 2 cm, 2 points = 2–3 cm and 3 points = > 3 cm in length. RV trabeculations were scored as 0 = no enhancement, 1 = enhancement of one trabeculation, 2 = enhancement of 2–4 trabeculations and 3 = enhancement of more than 4 trabeculations. RV-left ventricular insertion points were scored either 0 or 1 for absence or presence of enhancements.

Fig. 2

Transaxial late gadolinium enhancement (LGE) image of a 14-year-old girl with tetralogy of Fallot (TOF). The arrows indicate anterior right ventricular (RV) wall enhancements 10 min after gadolinium-injection.

Fig. 3

Sagittal late gadolinium enhancement (LGE) image of a 15 year old boy with tetralogy of Fallot (TOF). The arrow indicates posterior ventricular junction enhancement 10 min after gadolinium-injection.

Fig. 4

A correlation between right ventricular end diastolic volume (RV EDV) and remote late gadolinium enhancement (LGE) score (r = 0.44, P = 0.0045, n = 40). B: remote late gadolinium enhancement (LGE) score of patients with severe pulmonary regurgitation (PR) (≥ 30%) when compared to patients with PR < 30% (P = 0.008, n = 40). C: correlation between post-operative follow-up time and remote late gadolinium enhancement (LGE) score (r = 0.53, P = 0.006, n = 25). Only patients with ≥ 20% pulmonary regurgitation were included to this analysis.

Fig. 5

A correlation between N-terminal pro-brain natriuretic peptide (NT-proBNP) and right ventricular end diastolic volume (r = 0.54, P < 0.0001, n = 83). B: correlation between N-terminal pro-brain natriuretic peptide (NT-proBNP) and right ventricular ejection fraction (r = − 0.41, P = 0.0002, n = 83).