The efficacy of cardiac findings in assessing the outcome in preterms with bronchopulmonary dysplasia.

OBJECTIVES: To evaluate if cardiac dysfunctions are important in assessing the outcome in newborns with Bronchopulmonary Dysplasia (BPD), by evaluating cardiac functions with N-terminal prohormone of brain natriüretic peptide (NT-proBNP) levels, M-mode and tissue doppler echocardiography at 6-12 mo of age.

METHODS: Twenty eight patients were retrospectively classified as mild, moderate and severe according to the diagnostic criterias for BPD. All cases were assessed with standard M-mode, tissue doppler echocardiography and NT-proBNP levels. Control group consisted of 28 healthy infants, having similar postnatal ages as patients and were assessed with standard M-mode and tissue doppler echocardiography.

RESULTS: The age of patients with BPD was 9.8 ± 2.3 mo and control group was 9.5 ± 2.6 mo. There was no significant difference between the postnatal ages of two groups (p > 0.05). Neither pulmonary hypertension nor pulmonary/tricuspid regurgitation was detected. The M-mode echocardiography measurements did not differ between patients and control group (p > 0.05). Tissue doppler echocardiography, tricuspid valve medial segment early diastolic myocardial relaxation velocity (TME') measurements of patients were found significantly lower, peak transtricuspid filling velocity in the early diastole (TE)/TME' ratios and isovolumetric relaxation time (IVRT) measurements were found significantly higher than control group (p < 0.05). Tricuspid E, TE/TLE' (Tricuspid valve lateral segment early diastolic myocardial relaxation velocity), TE/RVLE'(Right ventricular lateral segment early diastolic myocardial relaxation velocity), TE/TME' levels were also found as significantly abnormal in patients with severe BPD. A significant correlation was found between right ventricular diastolic disfunctions and severity of BPD (p < 0.05). No statistically significant difference was found between NT-proBNP levels, BPD stages and tissue doppler echocardiography measurements (p > 0.05).

CONCLUSIONS: This is the first study evaluating cardiac findings in patients with BPD by tissue doppler echocardiography and NT-proBNP at the same time. On the basis of cardiac evaluations, tissue doppler echocardiography measurements were found as significant and specific for the early assessment of right ventricular diastolic disfunctions.