CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 5, June 2012
274
AFRICA
Robotically controlled ablation for atrial fibrillation:
the first real-world experience in Africa with the Hansen
robotic system
FAIZEL LORGAT, EVAN PUDNEY, HELENA VAN DEVENTER, SAM CHITSAZ
Abstract
Background:
We report the first single-centre experience
in Africa with the Sensei X robotic navigation system in an
unselected subset of patients with atrial fibrillation (AF).
Methods:
Data were recorded prospectively of all consecutive
patients who underwent robotically assisted catheter abla-
tion therapy using the Sensei X robotic navigation system
at the Christiaan Barnard Memorial Hospital, Cape Town,
South Africa, from July 2009 to July 2010. Outcomes were
defined at one and nine months.
Results:
A total of 95 patients were included: 63% had
only AF and 37% had AF plus atrial flutter. AF was of the
persistent type in 81% of patients. The mean procedure,
fluoroscopy and ablation times were 220.6
±
89.6 min, 31.0
±
20.4 min, and 61.3
±
28.1 min, respectively. Both fluoroscopy
and procedure times were significantly longer for the first
19 patients compared with the remaining 76 patients (43.5
±
22.7 vs 27.8
±
18.5 min and 274.7
±
90.2 vs 207.1
±
84.7 min,
respectively,
p
=
0.002). The procedural endpoint of the study
was successfully achieved in all patients. After one attempt,
27% were discharged from hospital off anti-arrhythmic
drugs (AADs). At a median of nine months’ follow up, 74%
were AF-free off AADs, and 11% were AF-free on AADs,
yielding a total freedom from AF of 84% without any redo
procedures. Freedom from relapse after 1.12 procedures
was 88%.
Conclusion:
The Sensei X™ robotic navigation system offers
a safe and effective approach for the treatment of AF. There
was a learning curve with regard to fluoroscopy and proce-
dure time, after which point reduction in radiation exposure
and operator strain, as well as improvement in procedure
throughputs were even more pronounced.
Keywords:
atrial fibrillation, catheter ablation, atrial flutter,
robotic navigation, computer-assisted ablation
Submitted 28/11/11, accepted 24/2/12
Cardiovasc J Afr
2012;
23
: 274–280
DOI: 10.5830/CVJA-2012-015
Atrial fibrillation (AF) is the most common sustained cardiac
rhythm disturbance in the general population.
1
As life expectancy
and average age increase, it is estimated that the number of patients
affected by AF will increase 2.5-fold over the next five decades.
2
Uncontrolled AF may result in devastating complications such as
haemodynamic impairment and increased risk of stroke, which
in turn have a dramatic impact on quality of life, morbidity
and mortality. Hence, it is imperative to advance treatment
options available for patients suffering from this condition.
Over the past decade, catheter ablation has been proven to
be effective in treating various types of arrhythmias. According
to the latest guidelines, catheter ablation is indicated in cases
of symptomatic arrhythmias refractory to conventional anti-
arrhythmia therapies.
3-6
Specifically, limited success of anti-
arrhythmia drugs in the treatment of AF has made this condition
the dominant indication for catheter ablation in high-volume
electrophysiology centres.
1
So far, two catheter-based approaches have emerged as
accepted strategies for AF treatment: (1) ostial segmental
disconnection of all pulmonary veins from the adjacent atrial
tissue, and (2) circumferential pulmonary vein ablation (CPVA).
6
The circumferential approach was found to be significantly more
effective than segmental ablation for paroxysmal AF. However,
these two seemingly different strategies are converging towards a
unified strategy (i.e. circumferential approach) and are reporting
similar success rates.
7
Regardless of strategy, however, the safety
and efficacy of these strategies and others under investigation
are highly operator dependent and require reproducible catheter
movements and optimal catheter stability and contact during
mapping and ablation energy delivery.
In recent years, remote catheter navigation systems
have been introduced to improve precision during catheter
manipulation, reduce physical demands on the operator,
minimise fluoroscopy time, and increase patients’ safety
by avoiding serious complications.
8
The Sensei X robotic
navigation system (Hansen Medical, Mountain View, CA)
and the Niobe magnetic navigation system (Stereotaxis, St
Louis, MO) are two commercially available remote catheter
navigation systems currently available on the market.
Performance of the Sensei X system has been evaluated in
American and European studies.
9-12
Researchers investigated
technical characteristics and outcomes of robotic AF ablation
and found that the complications and recurrence rates with the
robotic system were comparable to those of manual ablation,
13
while the amount of radiation exposure was significantly lower
with the robotic navigation.
14
The learning curve in early cases
resulted in longer procedure times at each centre, mostly due to
lack of experience with the set-up, which gradually improved.
15
In this article, we report the first real-world experience
in Africa with the Sensei X robotic navigation system in an
unselected subset of patients with predominantly persistent AF.
Department of Cardiology, Christiaan Barnard Memorial
Hospital, Cape Town, South Africa
FAIZEL LORGAT, MB ChB, PhD,
EVAN PUDNEY
HELENA VAN DEVENTER
Cardiac Biomechanics Laboratory, University of California
San Francisco, San Francisco, California, USA
SAM CHITSAZ, MD
