Discussion
The case illustrates that posterior atrial wall perforation can be
carried out in a conservative manner, without immediate subxiphoid
access. Despite infusion of heparin and ACT greater than 300 seconds,
all stages of ablation were performed without evidence of bleeding in
the pericardial space. However, negative pressure was maintained by JR
6F catheter throughout the procedure.
Fisher et al. were the first to describe the possible management
of hemopericardium in 2 patients in whom a long sheath was inadvertently
positioned in the pericardial space, using the sheath itself to draw
blood without the need for subxiphoid puncture(8).
Our group previously reported 2 cases in which, similarly, perforation
in the posterior wall was identified and the ablation performed with
isolation of the 4 pulmonary veins(9). In both cases
only a small amount of blood was identified in the pericardial
space. However, the operator opted to perform subxiphoid puncture at the
end of the procedure with maintenance of negative pressure in the
pericardial space through this access after the removal of
the transseptal sheath from the pericardial space. The feasibility of
the transatrial access was then demonstrated in a swine model(10).
To the best of our knowledge, this is the first case in which, despite
the atrial perforation with the placement of the sheath within the
pericardial space, no hemopericardium occurred and
no subxiphoid puncture was performed. Our hypothesis is that the
bleeding did not occur because the sheath itself, once positioned in the
pericardial space, worked like a plug, preventing bleeding despite
heparin infusion. Another hypothesis is that the maintenance of negative
pressure throughout the procedure might facilitate the adhesion of the
parietal to the visceral pericardium, which avoided further bleeding
after sheath removal.