Atrial and Brain Natriuretic Peptide Secretion After Percutaneous Closure of the Left Atrial Appendage With the Watchman Device.

Objective: To evaluate the effect of transcatheter closure of the left atrial appendage (LAA) with the Watchman device on the secretion of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP).

Background: The LAA plays an important role in the regulation of intravascular volume via release of ANP and BNP. To date, there are no data suggesting substantial effects of hormonal interaction after percutaneous LAA closure for prevention of thromboembolic events in patients with non-valvular atrial fibrillation.

Methods: From October 2009 until May 2010, transcatheter LAA closure using the Watchman device was performed in 31 patients with non-valvular atrial fibrillation. Venous blood samples were obtained before, immediately after device implantation, and prior to discharge for ANP and BNP measurements.

Results: LAA closure resulted in a significant increase in ANP and BNP levels immediately after the procedure compared with baseline measurements (ANP: from 241 ± 34 pg/mL to 329 ± 30 pg/mL, P<.05; BNP: from 579 ± 196 pg/mL to 698 ± 211 pg/mL, P<.05), and a significant decrease prior to discharge compared with baseline values (ANP: from 241 ± 34 pg/mL to 149 ± 30 pg/mL, P<.001; BNP: from 579 ± 196 pg/mL to 429 ± 147 pg/mL, P<.001).

Conclusions: These results suggest that percutaneous closure of the LAA results in an intermittent distribution of the vasoactive hormones ANP and BNP followed by a significant attenuation of ANP and BNP secretion in the early postprocedural period. The clinical impacts of these findings need to be evaluated in further studies.