The goal of this study is to evaluate whether NT-proBNP plasma levels may help as a screening biomarker for monitoring right ventricular dilatation, pulmonary regurgitation and the onset of heart failure in patients with repaired Tetralogy of Fallot. Our single-centre observational prospective study involved 43 patients (15.1years, SD=8) with corrected Tetralogy of Fallot. Data collection included: clinical parameters (electrocardiogram, chest X-ray, NYHA scale, time since last surgery), biochemistry (NT-proBNP levels) and MRI values (ventricular volumetry, pulmonary flow assessment). Mean time since last surgery was 13.5years (SD=7.8). There was a statistically significant correlation between the NT-proBNP levels (187.4pg/ml, SD=154.9) and right ventricular dilatation for both the right ventricular end-diastolic volume (124.9ml/m2, SD=31.2) (Pearson=0.19, p<0.01) and end-systolic volume (56.1ml/m2, SD=18.8) (Pearson=0.21, p<0.01) and also with the pulmonary regurgitation fraction (36.5%, SD=16, Pearson=0.12, p<0.01). No significant correlation was found between NT-proBNP and right ventricular ejection fraction (54.6%, SD=10.6, Pearson=-0.07), left ventricular ejection fraction (59.9%, SD=7.1, Pearson=-0.18) or any clinical parameters. The receiver operating curve analysis evidenced that a NT-proBNP cut-off value above 133.2pg/ml predicted the presence of dilated right ventricular end-diastolic and end-systolic volumes over centile 95 (sensitivity 82 and 83% and specificity 93 and 79%, respectively). In conclusion, in patients with surgically corrected Tetralogy of Fallot, NT-proBNP levels correlate with right ventricular dilatation and the degree of pulmonary regurgitation. Ambulatory determination of NT-proBNP might be an easy, readily available and cost-effective alternative for MRI follow-up evaluation of these patients.
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