Secretion of A-type and B-type natriuretic peptides into the bloodstream and pericardial space in children with congenital heart disease

AbstractObjectiveTo determine the secretion of A-type and B-type natriuretic peptides into the bloodstream and pericardial space in children with congenital heart disease.MethodsPlasma and pericardial fluid samples were obtained from 77 patients undergoing total correction for congenital heart disease. All patients underwent detailed right-sided and left-sided cardiac catheterization preoperatively.ResultsA-type natriuretic peptide levels in pericardial fluid were lower than those in plasma (33.0 ± 23.1 versus 39.8 ± 33.6 pg/mL, P < .05), and B-type natriuretic peptide levels in pericardial fluid showed marked elevations compared with those in plasma (231.9 ± 305.6 versus 19.8 ± 29.3 pg/mL, P < .0001). The A-type and B-type natriuretic peptide levels in plasma correlated with those in pericardial fluid (R = .522, P < .0001; R = .595, P < .0001). For A-type and B-type natriuretic peptide levels in plasma, the relation with biventricular volume had the highest correlation (R = .669, P < .0001; R = .652, P < .0001). The patients with a pulmonary-to-systemic flow ratio greater than 2 (n = 19) had high levels of natriuretic peptides not only in plasma (58.3 ± 43.2, 40.5 ± 49.4 pg/mL, P < .05) but also in pericardial fluid (44.4 ± 31.5, 287.2 ± 198.5 pg/mL, P < .05), and higher correlation between A-type and B-type natriuretic peptide plasma levels and left ventricular volume (R = .913, P < .0001; R = .787, P < .0001).ConclusionsB-type natriuretic peptide is secreted not only into the bloodstream but also into the pericardial space in children with congenital heart disease. Natriuretic peptide levels in plasma correlated well with biventricular volume. The left ventricle was considered to be the main source of secreted natriuretic peptides in the patients with a pulmonary-to-systemic flow ratio greater than 2

Evaluation of a novel device for left atrial appendage exclusion: The second-generation atrial exclusion device

BackgroundThe left atrial appendage is a frequent source of thromboemboli in patients with atrial fibrillation. Exclusion of the left atrial appendage may reduce the risk of stroke in patients with atrial fibrillation. The atrial exclusion device, previously developed to perform left atrial appendage exclusion on a beating heart, was modified to accommodate different anatomic patterns of the human left atrial appendage and to ensure uniform pressure and occlusion. The purpose of this study was to evaluate this second-generation atrial exclusion device during a midterm period in a canine model.MethodsTen mongrel dogs (mean weight 28.9 ± 4.6 kg) were used in this study. The atrial exclusion device, constructed from two parallel and rigid titanium tubes and two nitinol springs with a knit-braided polyester fabric, was implanted at the base of the left atrial appendage through a left thoracotomy on a beating heart using a specially designed delivery tool. Dogs were evaluated at 30 days (n = 4) and 90 days (n = 6) by epicardial echocardiography, left atrial and coronary angiography, gross pathology, and histologic inspection.ResultsDevice implantation was performed without complications in all dogs. Complete left atrial appendage exclusion without device migration or hemodynamic instability was confirmed, and there was no damage to the left circumflex artery or pulmonary artery. Macroscopic and microscopic assessments revealed favorable biocompatibility during midterm follow-up.ConclusionThe atrial exclusion device enabled rapid, reliable, and safe exclusion of the left atrial appendage. Clinical application may provide a new therapeutic option for reducing the risk of stroke in patients with atrial fibrillation