Neurohormonal and cytokine fluctuations following transcatheter closure for an atrial septal defect

Inflammation and neurohormonal activation are considered to be involved in the development of earlier and/or later complications in congenital heart disease patients, even after a successful repair of the lesion. It is not yet clarified what is the role of the therapeutic interventions in the occurrence of such a response and how it could be associated with possible postoperative complications.

We sought to assess the inflammatory and neurohormonal response to transcatheter closure of secundum type atrial septal defects (ASD) over a six-month follow-up period. We also evaluated the association between the respective markers and catheterization data as well as echocardiographic measurements.

Plasma concentrations of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), N-terminal-proatrial natriuretic peptide (NT-proANP) and N-terminal-probrain natriuretic peptide (NT-proBNP) were assessed and echocardiographic measurements were performed in twenty-eight patients with atrial septal defect prior to, and at the first, second and sixth months post transcatheter closure. Thirty-three age-matched healthy volunteers were also enrolled.

IL-6 plasma levels, although higher preoperatively, [physical logarithm (ln) IL-6: 3.37±0.66 vs 2.92±0.44 pg/ml, p=0.015], reached control levels postoperatively, at the end of the third month, whereas TNF-α and IL-10 were not influenced by the procedure. NT-proANP levels were elevated preoperatively compared to the control group (ln NT-proANP 3.78±0.572 vs 3.48±0.30, p=0.031), with a further significant increase during the 1st month (ln NT-proANP 3.78±0.572 vs 4.2±0.42, p=0.006), following the pattern of the left atrial volume enlargement, and remained high even 6 months after the procedure .On the other hand, the initially normal concentrations of NT-proBNP, after a transient significant increase during the first month postoperatively (ln NT-proBNP 3.56±0.94 vs 4.58±0.91, p<0.0001) returned to the controls' levels at the end of the third month. Preoperative concentrations of NT-proANP positively correlated with NT-proBNP concentrations and pulmonary to systemic flow ratio (Qp/Qs).

Transcatheter closure could improve, on a mid- term basis, the inflammatory process but natriuretic peptides' secretion continues in parallel with left atrial volume increase. Further follow up is required to determine the long-term progress of the inflammatory and neurohormonal response to the procedure.