Case presentation
An
80-year-old male patient, had history of coronary atherosclerotic heart
disease, hypertension, and implantation of permanent double chamber
cardiac pacemaker, AF, CHA2DS2-VASc
score of 4, HAS-BLED score of 3. The patient was referred to
transcatheter LAAO because of reluctant long-term oral anticoagulants.
Transesophageal echocardiography (TEE) excluded the thrombus formation
and measured the diameter of inlet and waist of LAA. The patient refused
to use intracardiac echocardiography due to financial constraint.
Implantation of LAA device was guided by X-ray fluoroscopy and
angiography without general anesthesia with only perioperative use of
TEE3. During LAAO
procedure, the shape and size of LAA was determined by angiogram. We
chose the occluder with diameter of 26mm lobe/38mm disc (LAmbre 2638,
Lifetech Scientific, China). Under continuous fluoroscopy monitoring, the
occluder was in position with no obvious residual flow in a correct tug
test, and then it was fully released. The method referred the COST
principle (umbrella deployed beyond Circumflex artery; umbrella fully
Open; peri-device optimal Sealing; device stability confirmed by Tug
test)2. The occluder,
however, unexpectedly dislodged to left atrium (LA) at the end of
procedure. Instantly, a LASSO catheter (Nav, Biosense Webster, America)
was introduced to entrap the tumbling device to prevent it from falling
into left ventricle (Figure 1A, online Video 1). And the department of
cardiovascular surgery was ready for unexpected needs. The normal head
foreign body removal forceps (Mousetooth alligator forceps, Alton
Medical Limited, China) was sent to LA through another 8.5F transseptal
sheath (L1, Synaptic Medical, China). We tried many times, but still
failed to grasp the device. After that, we adjusted LASSO to access the
center of occluder, while it suddenly migrated to left ventricle, and
instantly flowed into
aorta
arch (Figure 1B). The patient was asymptomatic and with stable heart
rhythm and blood pressure. A 14F flexible sheath (FlexCath, Medtronic,
America) was delivered via right femoral artery approach to adjust and
access the center of sealing disc,
thereafter the aforementioned forceps
were sent out, and finally after several attempts the sealed disc center
was caught (Figure 1C-D, online Video 2); the LAA occluder was smoothly
retrieved into the
sheath
(Figure 1E, online Video 3). The device was completely destroyed due to
the pulling and squeezing inside the sheath (Figure 1F). Repeat aorta
arch angiography showed no vascular complications. The patient refuted
further implantation of other devices, and returned to ward with stable
hemodynamic parameters, without pericardial effusion and injury of
valves.
Discussion
Percutaneous retrieval of the dislodged LAmbre occluder has been
depicted in a canine model with a 14F adjustable curved sheath and
forceps4. We herein
reported a human case using this strategy to safely retrieve the LAmbre
device. The reasons for dislodgement may associate with: improper size,
incorrect apposition, a shallow landing zone, vigorous tug test, passive
or active movement before complete
endothelialization4. In
the present case, dislocation may be on account of the complex
structure–a cauliflower shape with a wide ostium and a short distance
from each lobe to the common ostium, and the over sizing of device. We
however could not totally exclude the influence of intraoperative
imaging, though previous study reported the potential feasibility of
simplified procedure using fluoroscopy
only5. Unlike the other
two types of devices, i.e. Watchman and Amplatzer Cardiac Plug,
referring to use snare to retrieve, the retrieving tool of LAmbre was
referred to use the disposable grasping forceps (JIUHONG, Changzhou,
China). The fixed disc of LAmbre is too fragile to be caught, but the
sealed disc, woven with nickel titanium alloy wire, could be hauled and
contracted into the sheath integrally by catching the wire of center
area of the metal disc. Therefore, as recently reported in a canine
model4, for successful
retrieval, it is important to get close to the center of disc (using a
hard guided wire and a pig tail duct) and grasp device with the forceps.
In present case, when in LA, it is probable that the used sheath was not
as flexible and large as to access the effective seizing position. We
should introduce a 14F adjustable curved
sheath4. Fortunately,
after fleeing from LA, the device was not trapped in left ventricle and
quickly embolized in aorta arch, giving us another chance to retrieve.
The 14F flexible sheath is able to adjust satisfactory angles and get
close to the right position so as to catch the occluder smoothly by
forceps. Therefore, a 14F flexible sheath and forceps can be used to
safe percutaneous retrieval of LAmbre in
aorta.