Honěk J, Srámek M, Sefc L, Januška J, Fiedler J, Horváth M, Tomek A, Novotný S, Honěk T, Veselka J. Journal of American College of Cardiology: Cardiovascular Interventions. 2014 Apr;7(4):403–8. doi: 10.1016/j.jcin.2013.12.199. Epub 2014 Mar 14. IF: 7.44
OBJECTIVES: This study sought to evaluate the effect of catheter-based patent foramen ovale (PFO) closure on the occurrence of arterial bubbles after simulated dives.
BACKGROUND: PFO is a risk factor of decompression sickness in divers due to paradoxical embolization of bubbles. To date, the effectiveness of catheter-based PFO closure in the reduction of arterial bubbles has not been demonstrated.
METHODS: A total of 47 divers (age 35.4 ± 8.6 years, 81% men) with a PFO (PFO group) or treated with a catheter-based PFO closure (closure group) were enrolled in this case-controlled observational trial. All divers were examined after a simulated dive in a hyperbaric chamber: 34 divers (19 in the PFO group, 15 in the closure group) performed a dive to 18 m for 80 min, and 13 divers (8 in the PFO group, 5 in the closure group) performed a dive to 50 m for 20 min. Within 60 min after surfacing, the presence of venous and arterial bubbles was assessed by transthoracic echocardiography and transcranial color-coded sonography, respectively.
RESULTS: After the 18-m dive, venous bubbles were detected in 74% of divers in the PFO group versus 80% in the closure group (p = 1.0), and arterial bubbles were detected in 32% versus 0%, respectively (p = 0.02). After the 50-m dive, venous bubbles were detected in 88% versus 100%, respectively (p = 1.0), and arterial bubbles were detected in 88% versus 0%, respectively (p < 0.01).
CONCLUSIONS: No difference was observed in the occurrence of venous bubbles between the PFO and closure groups, but the catheter-based PFO closure led to complete elimination of arterial bubbles after simulated dives. (Nitrogen Bubble Detection After Simulated Dives in Divers With PFO and After PFO Closure; NCT01854281).