Occluding the pulmonary artery to improve detection of patent foramen ovale during ventricular assist device placement.

Unrecognized patent foramen ovale (PFO) in patients after left ventricular assist device (VAD) placement could cause significant hypoxemia and paradoxical embolism. We aim to improve the techniques for PFO detection in this patient population before left ventricular device initiation. We evaluated the effects of main pulmonary artery occlusion on patients' hemodynamic and detection of PFO by transesophageal echocardiography (TEE). We compared between the standard and pulmonary artery occlusion technique. Sixty-two patients with ASA physical status class IV were studied. They presented with end-stage heart failure for left VAD placement. All patients received both Valsava maneuver and occlusion of their pulmonary arteries to assess their influence on detection of PFO. Occlusion of the main pulmonary artery consistently increased right atrial to left atrial pressure gradient. The PFO detection rate using TEE was significantly improved from 0% to 10% by this maneuver compared with the Valsava maneuver. Occlusion of the main pulmonary artery is a simple and effective method to improve PFO detection by TEE before left VAD initiation.