case_images: PMC553997_01
case_images: ICE during atrial diastole before the jump of the transseptal needle into the oval fossa. In this patient the LA cavity has a crescent-like shape at this time point of the cardiac cycle. Ao - non-coronary sinus of the aorta; CT - terminal crest; FO - oval fossa; LA - left atrium; LAFW - left atrial free wall; RA - right atrium; TSN - transseptal needle.
case_images: 1476-7120-3-5-1.jpg
case_images: PMC553997_01_1476-7120-3-5-1.jpg
case_images: F1
case_images: TEE.mpeg for the TEE), however the left heart catheterization was deemed feasible. ICE performed at the electrophysiology laboratory (catheter Ultra ICE 9900, 9 MHz, EP Technologies, Boston Scientific Corp., San Jose, CA, USA connected to a console ClearView Ultra, Boston Scientific Corp., San Jose, CA, USA) as a routine part of the transseptal puncture showed more detailed picture of the intracardiac anatomy - dilated aortic root, enlarged right atrium displacing the IAS towards the LA free wall, and small oval fossa with flapping motion of the fossa ovalis membrane. The distance between the IAS and the LA free wall during the atrial diastole was small (Fig. 1).
case_images: ICE during atrial systole before the jump of the transseptal needle into the oval fossa. The LA cavity is virtually missing at this time point of the cardiac cycle. Ao - non-coronary sinus of the aorta; CT - terminal crest; FO - oval fossa; RA - right atrium; RV - right ventricle.
case_images: 1476-7120-3-5-2.jpg
case_images: PMC553997_01_1476-7120-3-5-2.jpg
case_images: F2
case_images: During the atrial contraction the LA cavity appeared almost obliterated and the fossa ovalis membrane virtually touched the LA free wall, thus making the transseptal puncture potentially dangerous (Fig. 2) (See Additional file 2: ICE1.mpeg for the unusual intracardiac anatomy).
case_images: ICE after the jump of the transseptal needle into the oval fossa. The needle tip points towards the aorta. Ao - non-coronary sinus of the aorta; LA - left atrium; RA - right atrium; TSN - transseptal needle.
case_images: 1476-7120-3-5-3.jpg
case_images: PMC553997_01_1476-7120-3-5-3.jpg
case_images: F3
case_images: That was also deemed a condition predisposing to complicated transseptal puncture (Fig. 3) (See Additional file 3: ICE2.mpeg for the sliding of the transseptal needle towards the aorta).