Microembolic signal counts increase during hyperbaric exposure in patients with prosthetic heart valves
(2001) In Journal of Thoracic and Cardiovascular Surgery 122(6). p.1142-1146- Abstract
- BACKGROUND: Patients with prosthetic heart valves have an increased risk of thromboembolic events, and transcranial Doppler sonography reveals microembolic signals. Whereas microembolic signals were initially assumed to be of particulate matter, recent studies suggest that they are partially gaseous in origin. If this is true, alteration of environmental pressure should change microembolic signal counts. We undertook this study to evaluate the influence of hyperbaric exposure on microembolic signal counts in persons with prosthetic heart valves. METHODS AND RESULTS: Microembolic signal counts were monitored by transcranial Doppler sonography of both middle cerebral arteries under normobaria (normobaria 1), 2 subsequent periods of... (More)
- BACKGROUND: Patients with prosthetic heart valves have an increased risk of thromboembolic events, and transcranial Doppler sonography reveals microembolic signals. Whereas microembolic signals were initially assumed to be of particulate matter, recent studies suggest that they are partially gaseous in origin. If this is true, alteration of environmental pressure should change microembolic signal counts. We undertook this study to evaluate the influence of hyperbaric exposure on microembolic signal counts in persons with prosthetic heart valves. METHODS AND RESULTS: Microembolic signal counts were monitored by transcranial Doppler sonography of both middle cerebral arteries under normobaria (normobaria 1), 2 subsequent periods of hyperbaria (2.5 and 1.75 bar), and a second period of normobaria (normobaria 2) in 15 patients with prosthetic heart valves. Each monitoring period lasted 30 minutes. Compression and decompression rates were 0.1 bar/min. Microembolic signal counts increased from 20 (12-78) at normobaria 1 to 79 (30-165) at 2.5 bar (P <.01 vs normobaria 1 and 2), decreased to 44 (18-128) at 1.75 bar (P <.01 vs normobaria 1 and 2.5 bar; P <.001 vs normobaria 2), and returned to 20 (8-96) at normobaria 2 (values are medians and 95% confidence intervals). CONCLUSIONS: Our results strongly suggest that gaseous bubbles are underlying material for part of the microembolic signals detected in patients with prosthetic heart valves. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1122734
- author
- Baumgartner, R W ; Frick, A ; Kremer, Christine LU ; Oechslin, E ; Russi, E ; Turina, J and Georgiadis, D
- organization
- publishing date
- 2001
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Thoracic and Cardiovascular Surgery
- volume
- 122
- issue
- 6
- pages
- 1142 - 1146
- publisher
- Mosby-Elsevier
- external identifiers
-
- pmid:11726888
- scopus:0035783915
- pmid:11726888
- ISSN
- 1097-685X
- DOI
- 10.1067/mtc.2001.117282
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Neurology, Malmö (013027010)
- id
- 7a52c041-8cab-4eb0-b840-c1412822dfcc (old id 1122734)
- date added to LUP
- 2016-04-01 15:32:55
- date last changed
- 2022-01-28 05:54:30
@article{7a52c041-8cab-4eb0-b840-c1412822dfcc, abstract = {{BACKGROUND: Patients with prosthetic heart valves have an increased risk of thromboembolic events, and transcranial Doppler sonography reveals microembolic signals. Whereas microembolic signals were initially assumed to be of particulate matter, recent studies suggest that they are partially gaseous in origin. If this is true, alteration of environmental pressure should change microembolic signal counts. We undertook this study to evaluate the influence of hyperbaric exposure on microembolic signal counts in persons with prosthetic heart valves. METHODS AND RESULTS: Microembolic signal counts were monitored by transcranial Doppler sonography of both middle cerebral arteries under normobaria (normobaria 1), 2 subsequent periods of hyperbaria (2.5 and 1.75 bar), and a second period of normobaria (normobaria 2) in 15 patients with prosthetic heart valves. Each monitoring period lasted 30 minutes. Compression and decompression rates were 0.1 bar/min. Microembolic signal counts increased from 20 (12-78) at normobaria 1 to 79 (30-165) at 2.5 bar (P <.01 vs normobaria 1 and 2), decreased to 44 (18-128) at 1.75 bar (P <.01 vs normobaria 1 and 2.5 bar; P <.001 vs normobaria 2), and returned to 20 (8-96) at normobaria 2 (values are medians and 95% confidence intervals). CONCLUSIONS: Our results strongly suggest that gaseous bubbles are underlying material for part of the microembolic signals detected in patients with prosthetic heart valves.}}, author = {{Baumgartner, R W and Frick, A and Kremer, Christine and Oechslin, E and Russi, E and Turina, J and Georgiadis, D}}, issn = {{1097-685X}}, language = {{eng}}, number = {{6}}, pages = {{1142--1146}}, publisher = {{Mosby-Elsevier}}, series = {{Journal of Thoracic and Cardiovascular Surgery}}, title = {{Microembolic signal counts increase during hyperbaric exposure in patients with prosthetic heart valves}}, url = {{http://dx.doi.org/10.1067/mtc.2001.117282}}, doi = {{10.1067/mtc.2001.117282}}, volume = {{122}}, year = {{2001}}, }