The aim of the present study was to characterise the morphology of patent foramen ovale (PFO) by a standardised protocol during transoesophageal echocardiography and to estimate the final and successful position of PFO-occluding devices (PFO-Star) by evaluation of parameters determined by echocardiography. The echoacardiographic parameters of septum- and PFO-morphology determined before the intervention were analysed with regard to choosing the optimal device-system for transcatheter PFO-closure. Transoesophageal echocardiography combined with application of contrast-media was performed in 31 patients before, during and after PFO-closure by using the PFO-Star-Device. The pre-interventional morphological parameters were compared with the result after PFO-closure. Quantitative contrast-bubble-shunting, PFO-channel-length and Vena contracta detected by colour flow Doppler do not show any correlation. PFO-channel-length in cases with small angles between aorta and septum seems to be associated with higher risk of clinically irrelevant device-shift as well as residual shunt.
A standardised procedure in transoesophageal echocardiography is suitable for characterising the morphology of PFO. Neither the morphology in 2D-imaging nor the amount of shunt microbubble seen in the left atrium allows a conclusive statement about the PFO size. For obtaining an optimal closure result, it is important to identify the channel-length and the distance between the interatrial septum and the PFO together with the angles between septum and the surrounding intracardiac structures.
Do results of transoesophageal echocardiography during closure of patent foramen ovale influence interventional therapy?