title: Patent foramen ovale diagnosis: The importance of provocative maneuvers.
abstract: Patent foramen ovale (PFO) is a frequent congenital anomaly, but massive right-to-left shunt (RTLS) is normally prevented by higher pressures in left heart chambers. However, mechanical ventilation with positive end-expiratory pressure (PEEP) can significantly increase right atrial pressure, accentuating the RTLS, mainly after major cardiothoracic surgery. We report a patient admitted to the intensive care unit after cardiac surgery. Pre- and intraoperative transesophageal echocardiography only described an aneurysmal interatrial septum with no shunt. However, high-PEEP ventilation induced a paradoxical response with life-threatening hypoxemia, triggering further echocardiographic evaluation, revealing massive RTLS across a stretch PFO. Provocative maneuvers (Valsalva/PEEP) significantly increase echocardiographic sensitivity, unmasking silent PFO. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:58-61, 2017.
authors.affiliation: Anesthesia and Intensive Care, Fondazione IRCCS Policlinico S. Matteo, University of Pavia, Pavia, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Mongodi
authors.affiliation: Anesthesia and Intensive Care, Fondazione IRCCS Policlinico S. Matteo, University of Pavia, Pavia, Italy.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Via
authors.affiliation: Anesthesia and Intensive Care, Fondazione IRCCS Policlinico S. Matteo, University of Pavia, Pavia, Italy.
authors.forename: Mariachiara
authors.initials: M
authors.lastname: Riccardi
authors.affiliation: Anesthesia and Intensive Care, Fondazione IRCCS Policlinico S. Matteo, University of Pavia, Pavia, Italy.
authors.forename: Guido
authors.initials: G
authors.lastname: Tavazzi
authors.affiliation: Cardiothoracic Surgery, Fondazione IRCCS Policlinico S. Matteo, University of Pavia, Pavia, Italy.
authors.forename: Andrea Maria
authors.initials: AM
authors.lastname: D'Armini
authors.affiliation: Anesthesia and Intensive Care, Fondazione IRCCS Policlinico S. Matteo, University of Pavia, Pavia, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Maurelli
authors.affiliation: Anesthesia and Intensive Care, Fondazione IRCCS Policlinico S. Matteo, University of Pavia, Pavia, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Braschi
authors.affiliation: Anesthesia and Intensive Care, Fondazione IRCCS Policlinico S. Matteo, University of Pavia, Pavia, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Mojoli
mesh_terms: D000368:Aged; D017548:Echocardiography, Transesophageal / Q000379:methods*; D054092:Foramen Ovale, Patent / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D008297:Male; D011175:Positive-Pressure Respiration; D018615:Ultrasonography, Doppler, Color / Q000379:methods*; D014636:Valsalva Maneuver
keywords: echocardiography; paradoxical response to positive end-expiratory pressure; patent foramen ovale; provocative maneuvers; right-to-left shunt