Nitrogen Bubble Detection After Simulated Dives in Divers With PFO and After PFO Closure

Patent Foramen Ovale Clinical Trial

Official title:

Nitrogen Bubble Detection After Simulated Dives in Divers With PFO and After PFO Closure

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01854281
• Other study ID #: EK-1929/12
• Status: Completed
• Phase: N/A
• First received: May 10, 2013
• Last updated: October 28, 2013
• Start date: May 2013
• Est. completion date: July 2013

Study information

• Verified date: October 2013
• Source: University Hospital, Motol
• Contact: n/a
• Is FDA regulated: No
• Health authority: Czech Republic: Ethics comittee of the University hospital Motol
• Study type: Observational

Clinical Trial Summary

The aim of this study is to determine whether catheter-based closure of patent foramen ovale is effective in preventing paradoxical embolization of nitrogen bubbles after simulated dives.

Description:

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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 47
• Est. completion date: July 2013
• Est. primary completion date: July 2013
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 19 Years and older

Eligibility

Inclusion Criteria:

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

Study Design

Observational Model: Case Control, Time Perspective: Cross-Sectional

Related Conditions & MeSH terms

• Foramen Ovale, Patent
• Patent Foramen Ovale

Locations

Country	Name	City	State
Czech Republic	Department of Cardiology, University Hospital Motol	Prague

Sponsors (1)

Lead Sponsor	Collaborator
University Hospital, Motol

Country where clinical trial is conducted

Czech Republic, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Arterial Nitrogen Bubbles After Surfacing	Arterial gas bubbles are detected by transcranial doppler ultrasonography. Positive outcome is 1 or more bubbles detected.	assesed within 1 hour after surfacing	Yes