Case report of two challenging cases
The treatment of persistent atrial fibrillation (PSAF) remains a
challenge for electrophysiologists. Nowadays, isolation of the pulmonary
veins (PVI) is a routinely applied, well proven and accepted
intervention. Despite this, some patients are in refractory atrial
fibrillation (AF) even after 2 or more procedures. Others are unable to
receive another catheter ablation due to previous cardiac interventions.
The Convergent procedure or the endoscopic epicardial unipolar ablation
as stand-alone might be a good option for this type of patients. The
Convergent procedure is a hybrid AF ablation procedure in which the
surgeon via subxiphoid access performs a set of lesions on the posterior
wall of the left atrium1. Then, a cardiac electrophysiologist maps and
completes isolation of the pulmonary veins and posterior wall. This
combined procedure can be performed in a single stage (same day)
setting, or in a staged setting.
Here we report on two of these cases from our clinic:
The first case is a 78 years old female patient with long standing
persistent AF who underwent a TAVI procedure in our institution 3 months
before the epicardial ablation.
The patient had undergone one pharmacologic cardioversion in the past,
and was in NYHA class III with an LVEF of 35%. The Convergent procedure
was performed in a staged setting, with 4 months between the epicardial
and the endocardial procedure. The epicardial ablation catheter
(EPi-Sense Coagulation Device, AtriCure, Inc.) (3 cm ablation coil and
is approximately 1 cm wide) was easily inserted via a subxiphoidal
approach, advanced and 19 ablation lines were placed under endoscopic
visualization. In order to avoid esophageal overheating, saline at room
temperature was infused into the pericardial space during epicardial
ablations, and the esophageal temperature was monitored with temperature
probe. Upon completion of the lesion set, a pericardial drain was left
in place. To complete the procedure, a transthoracic electrical
cardioversion was successfully performed. A post-operative transthoracic
echocardiogram (TTE) showed a fully functional nitinol aortic valve
prosthesis, unaffected by the temporary rise of intrapericardial
temperature. After a short episode of spontaneously terminating AF
during the stay on the normal ward, the patient was discharged home in
sinus rhythm (SR) on the ninth postoperative day. The patient presented
back to the clinic 3 months later in sinus rhythm, and underwent the
second stage of the hybrid procedure. This procedure consisted of
3D-mapping with NAVx (Endocardial Solutions, St. Jude Medical, Inc., St.
Paul, MN, USA) and pulmonary vein isolation and gap closing. After this
procedure, the patient left the hospital 3 days later and was discharged
while still in SR showing a improved ejection fraction of over 50%
The second case is a 63 years old male patient with paroxysmal AF who
underwent percutaneous transcatheter closure of patent foramen ovale
(PFO) in 2015 after having an embolic stroke. The patient presented to
the clinic with vertigo and arm accentuated hemiparesis. Because of the
PFO closure procedure the patient was not suitable for a conventional
transcatheter PVI approach. Therefore, only epicardial ablation appeared
to be a feasible option. The patient was in SR before the procedure. The
intervention was performed the same way as described above, and in this
case 23 ablation lines were placed. No intraprocedural complications
occurred, and no post ablation transthoracic electrical cardioversion
was necessary. On second postoperative day a transthoracic echo was
performed to evaluate the PFO. The echo showed no opening between the
right and left atrium and the closure device was in perfectly in place
despite the temporary temperature rise and forces applied to the left
atrium throughout the surgical procedure. Because of the PFO closure
device, no 3D-mapping was possible. The patient was discharged in SR
from the hospital
These two cases show that the endoscopic epicardial unipolar ablation as
a part of staged Convergent procedure or stand-alone can be performed
safely and with good results even in patient who underwent previous
cardiac interventions. In addition, it might be a good alternative in
patients in whom a primary transcatheter ablation is impossible due to
previous pathologies and interventions.
Lawrence S. Lee. Subxiphoid Minimally Invasive Epicardial Ablation
(Convergent Procedure) With Left Thoracoscopic Closure of the Left
Atrial Appendage. Operative Techniques in Thoracic and Cardiovascular
Surgery, 23, 152-165, 2018