Comparison of serum N-terminal pro-brain natriuretic peptide levels, conventional echocardiography, exercise parameters, and dyssynchrony measurements in Fontan patients

Introduction: Little data are available concerning the methods used in the long-term follow-up of Fontan patients. We analyzed the association between serum N-terminal pro-brain natriuretic peptide levels, conventional echocardiography findings, exercise parameters, and dyssynchrony measurements in patients who underwent Fontan surgery. Methods: This study included 28 patients who underwent Fontan surgery (mean age 12.8 +/- 4.36 years) and 27 healthy controls (mean age 12.5 +/- 3.76 years). Echocardiography examinations and exercise tests were performed in both groups. The systemic ventricle was examined via echocardiography, dyssynchrony measurement was performed, the systemic ventricular myocardial performance index was calculated, and serum N-terminal pro-brain natriuretic peptide levels were measured for all subjects. Results: Lower cardiac output, stroke volume, maximal work, chronotropic index, maximal oxygen uptake, and higher N-terminal probrain natriuretic peptide levels were observed in the Fontan group than in the control group (p < 0.05). A negative correlation was found between physical exercise parameters and N-terminal pro-brain natriuretic peptide levels and dyssynchrony measurements. Conclusion: Measurements of exercise capacity, serum N-terminal pro-brain natriuretic peptide levels, and dyssynchrony measurement were more valuable than conventional methods for assessing patients' clinical and functional status. Dyssynchrony measurements provided better information about ventricular status than did conventional echocardiography studies. While patients' systolic function determined by conventional echocardiography was normal, dyssynchronymeasurements showed the opposite result. The negative relationship between serum N-terminal pro- brain natriuretic peptide levels, dyssynchrony measurements, and exercise capacity suggests that these parameters should be investigated further in Fontan patients.