Nitrogen Bubble Detection After Simulated Dives in Divers With PFO and After PFO Closure
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|ClinicalTrials.gov Identifier: NCT01854281|
Recruitment Status : Completed
First Posted : May 15, 2013
Results First Posted : December 18, 2013
Last Update Posted : December 18, 2013
|Condition or disease|
|Patent Foramen Ovale|
The aim of this study is to determine whether catheter-based closure of patent foramen ovale (PFO) is effective in preventing paradoxical embolization of nitrogen bubbles after simulated dives.
Ultrasonographic detection of venous and arterial nitrogen bubbles will be performed in divers after surfacing from simulated dives in hyperbaric chambers. Divers will be observed after two different dive profiles - Dive A (dive to 18 m for 80 min bottom time) and dive B (dive to 50 m for 20 min bottom time), both performed according to US Navy Air decompression procedure 1996. For both dives two groups will be compared: Divers with PFO and divers after previous catheter-based closure of PFO.
The study will be observational. Sonographic detection of bubbles will be performed after simulated dives that are part of a training program of the divers. Two different dives, previously documented to generate significant amount of venous nitrogen bubbles, were chosen.
The primary end-point will be a positive transcranial doppler test (defined as one or more bubbles detected either during native breathing or after Valsalva maneuver).
Inclusion criteria are: 1) previously diagnosed PFO or a PFO that has been occluded by a catheter-based procedure, 2) signed informed consent
Exclusion criteria: 1) another dive performed in the preceding 24 hours, 2) another previously diagnosed right-to-left shunt, 3) disagreement to be included in the study
This study will be single-center.
|Study Type :||Observational|
|Actual Enrollment :||47 participants|
|Observational Model:||Case Control|
|Official Title:||Nitrogen Bubble Detection After Simulated Dives in Divers With PFO and After PFO Closure|
|Study Start Date :||May 2013|
|Actual Primary Completion Date :||July 2013|
|Actual Study Completion Date :||July 2013|
Patent foramen ovale dive A group
Divers with a previously diagnosed patent foramen ovale observed after Dive A.
Closure dive A group
Divers with a patent foramen ovale previously closed by a catheter-based procedure observed after Dive A.
patent foramen ovale dive B group
Divers with a previously diagnosed patent foramen ovale observed after Dive B.
closure dive B group
Divers with a patent foramen ovale previously closed by a catheter-based procedure observed after Dive B.
- Arterial Nitrogen Bubbles After Surfacing [ Time Frame: assesed within 1 hour after surfacing ]Arterial gas bubbles are detected by transcranial doppler ultrasonography. Positive outcome is 1 or more bubbles detected.
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01854281
|Department of Cardiology, University Hospital Motol|
|Prague, Czech Republic, 15006|
|Study Chair:||Josef Veselka, MD, PhD||Department of Cardiology, UH Motol|
|Study Director:||Jakub Honek, MD||Department of cardiology, UH Motol|