Discussion:
Left atrial appendectomy to prevent embolism in patients with rheumatic
heart disease and atrial fibrillation was first reported by Madden in
1949.4 In order to prevent embolism in patients with
AF undergoing LAA excision/exclusion, the surgical technique is
important. Years later, in his report of 306 patients who underwent maze
procedure and followed for up to 11.5 years, Dr. Cox reported two early
strokes with an incidence of 0.7% and only one more stroke in the
follow-up period.5 This benefit was ascribed to the
maze procedure restoring sinus rhythm and atrial transport, and
secondarily to obliteration of the LAA.
One of the complications of the clip is “too distal deployment” on the
LAA, leaving a residual stump greater than 1 cm. While the 1 cm figure
is an arbitrary number and its impact on future risk of stroke is
undetermined, it remains a considerable obstacle towards a wide
acceptance of this technique in the physician community. To this end, it
is important that implanting surgeon do all they can to make sure the
clip is deployed at the base of the LAA. The LAA may appear obliterated
on the TEE due to external pressure from the delivery system during
deployment of the clip. Once the clip is deployed and the delivery
system disconnected the stump may bounce back outward to show its real
size. It is also important that the appendage be evaluated in multiple
different views to make sure of obliteration. If recognized in the
operating room, such as happened in our case, one can deploy an
open-mouth V-Shaped clip under the previous clip. This is the first such
report of successful use of a second clip to obliterate the residual
stump. Because the Atriclip Pro V is more expensive, we only keep it as
a backup for such situations (because of its higher price) but continue
to use the more economical Atriclip Pro 2 for routine thoracoscopic
clipping. In conclusion, it is important to obliterate the LAA as close
to the base as possible. If there is a residual stump of a significant
size, approaching 1 cm, a second clip can be deployed under the first
clip to obliterate the LAA completely.