Contrast-enhanced CMR in patients after percutaneous closure of the left atrial appendage: A pilot study

Background: to evaluate the feasibility and value of first-pass contrast-enhanced dynamic and post-contrast 3d cmr in patients after transcatheter occlusion of left atrial appendage (laa) to identify incorrect placement and persistent leaks. methods. 7 patients with different occluder systems (n = 4 plaato; n = 2 watchman; n = 1 acp) underwent 2 contrast-enhanced (gd-dota) cmr sequences (2d truefisp first-pass perfusion and 3d-turboflash) to assess localization,artifact size and potential leaks of the devices. perfusion cmr was analyzed visually and semi-quantitatively to identify potential leaks. results: all occluders were positioned within the laa. the acp occluder presented the most extensive artifact size. visual assessment revealed a residual perfusion of the laa apex in 4 cases using first-pass perfusion and 3d-turboflash indicating a suboptimal laa occlusion. by assessing signal-to-time-curves the cases with a visually detected leak showed a 9-fold higher signal-peak in the laa apex (567 120% increase from baseline signal) than those without a leak (61 22%; p < 0.03). in contrast,the signal increase in laa proximal to the occluder showed no difference (leak 481 201% vs. no leak 478 125%; p = 0.48). conclusion: this cmr pilot study provides valuable non-invasive information in patients after transcatheter occlusion of the laa to identify correct placement and potential leaks. we recommend incorporating cmr in future clinical studies to evaluate new device types. © 2011 mohrs et al; licensee biomed central ltd.