Surgical Ablation for Atrial Fibrillation in Cardiac Surgery: A Meta-Analysis and Systematic Review.

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DOI: 10.1097/IMI.0b013e3181d9199b · Source: PubMed
Abstract
Objectives: : This meta-analysis sought to determine whether surgical ablation improves clinical outcomes and resource utilization compared with no ablation in adult patients with persistent and permanent atrial fibrillation (AF) undergoing cardiac surgery. Methods: : A comprehensive search was undertaken to identify all randomized (RCT) and nonrandomized (non-RCT) controlled trials of surgical ablation versus no ablation in patients with AF undergoing cardiac surgery up to April 2009. The primary outcome was sinus rhythm. Secondary outcomes included survival and any other reported clinically relevant outcome or indicator of resource utilization. Odds ratios (OR) and weighted mean differences (WMD) and their 95% confidence intervals (95% CI) were analyzed as appropriate using the random effects model. Heterogeneity was measured using the I statistic. Meta-regression was performed to explore the relationship between the benefit from surgical AF and duration of follow-up. Results: : Thirty-three studies met the inclusion criteria (10 RCTs and 23 non-RCTs) for a total of 4647 patients. The number of patients in sinus rhythm was significantly improved at discharge in the surgical AF ablation group versus (68.6%) the surgery alone group (23.0%) in RCTs (OR 10.1, 95% CI 4.5-22.5) and non-RCTs (OR 7.15, 95% CI 3.42-14.95). This effect on sinus rhythm (74.6% vs. 18.4%) remained at follow-up of 1 to 5 years (OR 6.7, 95% CI 2.8-15.7 for RCT, and OR 15.5, 95% CI 6.6-36.7 for non-RCT). The risk of all-cause mortality at 30 days was not different between the groups in RCT (OR 1.20, 95% CI 0.52-3.16) or non-RCT studies (OR 0.99, 95% CI 0.52-1.87). In studies reporting all-cause mortality at 1 year or more (up to 5 years), mortality did not differ in RCT studies (OR 1.21, 95% CI 0.59-2.51) but was significantly reduced in non-RCT studies (OR 0.54, 95% CI 0.31-0.96). Stroke incidence was not reduced significantly; however, in meta-regression, the risk of stroke decreased significantly with longer follow-up. Other clinical outcomes were similar between groups. Operation time was significantly increased with surgical AF ablation; however, overall impact on length of stay was variable. Conclusions: : In patients with persistent or permanent AF who present for cardiac surgery, the addition of surgical AF ablation led to a significantly higher rate of sinus rhythm in RCT and non-RCT studies compared with cardiac surgery alone, and this effect remains robust over the longer term (1-5 years). Although non-RCT studies suggest the possibility of reduced risk of stroke and death, this remains to be proven in prospective RCTs with adequate power and follow-up.
ORIGINAL ARTICLE
Surgical Ablation for Atrial Fibrillation in Cardiac Surgery
A Meta-Analysis and Systematic Review
Davy C. H. Cheng, MD,* Niv Ad, MD,† Janet Martin, PharmD, MSc(HTA&M),*‡
Eva E. Berglin, MD, PhD,§ Byung-Chul Chang, MD,¶ George Doukas, MD,
James S. Gammie, MD,** Takashi Nitta, MD, PhD,†† Randall K. Wolf, MD,‡‡
John D. Puskas, MD§§
Objectives: This meta-analysis sought to determine whether surgi-
cal ablation improves clinical outcomes and resource utilization
compared with no ablation in adult patients with persistent and
permanent atrial fibrillation (AF) undergoing cardiac surgery.
Methods: A comprehensive search was undertaken to identify all
randomized (RCT) and nonrandomized (non-RCT) controlled trials
of surgical ablation versus no ablation in patients with AF under-
going cardiac surgery up to April 2009. The primary outcome was
sinus rhythm. Secondary outcomes included survival and any other
reported clinically relevant outcome or indicator of resource utili-
zation. Odds ratios (OR) and weighted mean differences (WMD)
and their 95% confidence intervals (95% CI) were analyzed as
appropriate using the random effects model. Heterogeneity was
measured using the I
2
statistic. Meta-regression was performed to
explore the relationship between the benefit from surgical AF and
duration of follow-up.
Results: Thirty-three studies met the inclusion criteria (10 RCTs
and 23 non-RCTs) for a total of 4647 patients. The number of
patients in sinus rhythm was significantly improved at discharge in
the surgical AF ablation group versus (68.6%) the surgery alone
group (23.0%) in RCTs (OR 10.1, 95% CI 4.5–22.5) and non-RCTs
(OR 7.15, 95% CI 3.42–14.95). This effect on sinus rhythm (74.6%
vs. 18.4%) remained at follow-up of 1 to 5 years (OR 6.7, 95% CI
2.8 –15.7 for RCT, and OR 15.5, 95% CI 6.6–36.7 for non-RCT).
The risk of all-cause mortality at 30 days was not different between
the groups in RCT (OR 1.20, 95% CI 0.52–3.16) or non-RCT
studies (OR 0.99, 95% CI 0.52–1.87). In studies reporting all-cause
mortality at 1 year or more (up to 5 years), mortality did not differ
in RCT studies (OR 1.21, 95% CI 0.59 –2.51) but was significantly
reduced in non-RCT studies (OR 0.54, 95% CI 0.31– 0.96). Stroke
incidence was not reduced significantly; however, in meta-regres-
sion, the risk of stroke decreased significantly with longer follow-up.
Other clinical outcomes were similar between groups. Operation
time was significantly increased with surgical AF ablation; however,
overall impact on length of stay was variable.
Conclusions: In patients with persistent or permanent AF who
present for cardiac surgery, the addition of surgical AF ablation led
to a significantly higher rate of sinus rhythm in RCT and non-RCT
studies compared with cardiac surgery alone, and this effect remains
robust over the longer term (1–5 years). Although non-RCT studies
suggest the possibility of reduced risk of stroke and death, this
remains to be proven in prospective RCTs with adequate power and
follow-up.
Key Words: Meta-analysis, Atrial fibrillation, Surgical ablation,
Cardiac surgery.
(Innovations 2010;5:84–96)
A
nnual stroke risk in patients with nonrheumatic atrial
fibrillation (AF) not taking anticoagulation therapy is
4.5%.
1
Although antiarrhythmic therapies may be used for
rhythm or rate control,
2
these medications are not universally
effective, and chronic requirement for medication and anti-
coagulation may also adversely affect quality of life (QOL).
Accepted for publication February 11, 2010.
From the *Department of Anesthesia and Perioperative Medicine, Evi-
dence-Based Perioperative Clinical Outcomes Research Group (EPi-
COR), London Health Sciences Centre, The University of Western,
Ontario, London, ON, Canada; †Department of Cardiac Surgery,
Inova Heart and Vascular Institute, Falls Church, VA USA; ‡High
Impact Technology Evaluation Centre, London Health Sciences Cen-
tre, London, ON, Canada; §Department of Cardiothoracic Surgery,
Sahlgrenska University Hospital, Goteborg, Sweden; ¶Department of
Cardiac Surgery, Yonsei University College of Medicine, Seoul,
Korea; Department of Cardiothoracic Surgery, Glenfield Hospital,
Leicester, UK; **Division of Cardiac Surgery, University of Maryland
School of Medicine, Baltimore, MD USA; ††Department of Cardiac Sur-
gery, Nippon Medical School Main Hospital, Tokyo, Japan; ‡‡Deaconess
Hospital, Cincinnati, OH USA; and §§Division of Cardiothoracic Surgery,
Emory University, Atlanta, GA USA.
Support for the meta-analysis and a consensus conference was provided by
the International Society for Minimally Invasive Cardiothoracic Surgery
(ISMICS), which has received unrestricted educational grants from
industries that produce surgical technologies.
Disclosures: Eva E. Berglin, MD, PhD is a consultant for ATS Medical,
Inc., Minneapolis, MN USA. James S. Gammie, MD is a consultant for
ATS Medical, Inc., Minneapolis, MN USA. Randall K. Wolf, MD is a
consultant and receives royalties from AtriCure, West Chester, OH USA.
John D. Puskas, MD is a consultant for MAQUET, Wayne, NJ USA, and
Medtronic, Inc., Minneapolis, MN USA.
Address correspondence and reprint requests to Davy C. H. Cheng, MD,
LHSC-University Hospital, 339 Windermere Road, C3-172, London,
ON, Canada N6A 5A5. E-mail: davy.cheng@lhsc.on.ca.
Copyright © 2010 by the International Society for Minimally Invasive
Cardiothoracic Surgery
ISSN: 1556-9845/10/0502-0084
Innovations Volume 5, Number 2, March/April 201084
Patients with mitral valve and/or coronary artery dis-
ease who are having AF and are candidates for cardiac
surgery for valve repair/replacement or for coronary artery
bypass may be particularly suited to surgical AF ablation.
The Cox maze procedure was first performed in St. Louis in
1987 with the intention of eliminating AF by using incision
scars to block the abnormal electrical circuits (atrial macro-
reentry) that are characteristic of AF. This procedure requires
an extensive series of endocardial incisions through both atria
while on cardiopulmonary bypass, with access to the heart via
median sternotomy.
3
A series of systematic improvements
have subsequently been made, culminating in the 1992 Cox
maze III procedure, which is now considered to be the “gold
standard” for effective surgical treatment of AF. The Cox
maze III is sometimes referred to as the traditional maze, the
cut-and-sew maze, or simply the maze.
4
Further modifica-
tions of surgical AF ablation in subsequent years have fo-
cused on using various energy modalities to create lesion sets
with fewer cardiac incisions. These have included radiofre-
quency, ultrasound, microwave, laser, and cryotherapy.
A comprehensive and methodologically rigorous meta-
analysis of all comparative trials (randomized [RCT] and
nonrandomized trials [non-RCT]) is needed to better weigh
the risks and benefits of surgical ablation when added to other
planned cardiac surgery. Previous meta-analyses and system-
atic reviews have evaluated only RCTs, which may underes-
timate the risks if underpowered or of short duration.
5–7
This
systematic review and meta-analysis will attempt to address
the totality of evidence available to date.
Objectives
This systematic review with meta-analysis sought to
determine whether, in patients with AF undergoing cardiac
surgery, AF ablation improves clinical outcomes, QOL, and
resource-related outcomes when compared with cardiac sur-
gery without ablation. To answer this primary objective, the
following subquestions were prespecified to guide the sys-
tematic review:
1. Does ablation improve achievement of normal sinus
rhythm (NSR) before discharge, and is the effect sus-
tained long-term (6 months, 1 year, 3 years, 5 years, and
10 years)?
2. Does ablation reduce the need for pharmacologic treat-
ment of AF, direct current cardioversion, or pacemaker
insertion?
3. Does ablation reduce the risk of stroke, myocardial
infarction, heart failure, and other complications?
4. Does ablation improve QOL, functionality, or other
patient-reported outcomes?
5. Does ablation reduce total costs, intensive care unit (ICU)
and hospital length of stay, need for repeat cardiac surgery,
and readmissions, and is it cost-effective?
The secondary objective of this systematic review was
also defined as follows: in patients with AF undergoing
cardiac surgery plus ablation, how do different ablative tech-
niques compare with each other for conversion to NSR
(cut-and-sew, Cox mazes I, II, and III, pulmonary vein (PV)
isolation, radiofrequency ablation, ultrasound ablation, laser
ablation, and cryoablation)?
METHODS
This meta-analysis of comparative studies was performed
in accordance with state of the art methodological recommen-
dations (ie, as per QUOROM and MOOSE guidelines)
8,9
and
according to a protocol that prespecified outcomes, search strat-
egies, inclusion criteria, and statistical analyses.
Definition of Endpoints
Clinical endpoints of interest included achievement of
sinus rhythm, need for antiarrhythmic drugs, direct current
cardioversion, need for pacemaker, reexploration for bleed-
ing, major bleeding, transfusions, all-cause mortality, stroke
or transient ischemic attack (TIA), thromboembolic events,
myocardial infarction, low cardiac outcome, renal failure,
heart failure, New York Heart Association (NYHA) class,
reintervention for bleeding, reintervention for paravalvular
leak, patient satisfaction, functionality, QOL, cross-clamp
time, duration of surgery, ICU length of stay, total hospital
length of stay, costs, and cost-effectiveness. For this analysis,
AF was defined as recommended by the American College of
Cardiology, American Heart Association, and the European
Society of Cardiology guidelines, given in Table 1.
10
Literature Search
A comprehensive literature search of MEDLINE,
EMBASE, Cochrane CENTRAL, Current Contents, and
Science Citation Index, using keywords and variants of,
was performed from the earliest available date to April
2009. The most recent 6 months of relevant surgical and
anesthesia journals were searched by hand, and databases of
conference abstracts were reviewed electronically. Experts
were contacted to solicit additional reports of published or
unpublished clinical trials of surgical AF ablation, as negative
studies are more likely to be unpublished.
Inclusion Criteria
To be eligible for inclusion in the systematic review
and meta-analysis, trials had to be RCTs or non-RCTs com-
paring surgical AF ablation performed during cardiac surgery
versus cardiac surgery alone in patients undergoing valvular
or bypass surgery. All surgical AF ablation techniques were
eligible for inclusion, including the Cox maze procedure and
its variants (cut and sew), or ablation using other modalities
such as radiofrequency ablation, cryoablation, lasers, micro-
waves, whether applied biatrially or on a single atrium, with
or without pulmonary vein isolation. Subanalyses by type of
procedure and technology was planned to evaluate relative
TABLE 1. Atrial Fibrillation Definitions
AF Category Defining Characteristics
Paroxysmal Recurrent episodes that self-terminate in 7d
Persistent Recurrent episodes that last 7d
Permanent An ongoing long-term episode, resistant to electrical or
chemical cardioversion
Innovations Volume 5, Number 2, March/April 2010 Surgical Ablation for Atrial Fibrillation Review
Copyright © 2010 by the International Society for Minimally Invasive Cardiothoracic Surgery 85
efficacy. Studies of patients with lone AF and those under-
going catheter-based ablative procedures were excluded.
Data Extraction
Two authors (D.C. and J.M.) independently extracted
the following data points: baseline demographics including
number of patients, inclusion/exclusion criteria for patient,
and type of AF. Details of the ablative procedure and the
comparative conventional treatment provided were recorded.
Two authors extracted outcomes data and verified the extrac-
tion with each other. Discrepancies were resolved by consen-
sus. No unpublished study was found.
Data Analysis
Odds ratios (OR) and their 95% confidence intervals (95%
CI) were calculated for discrete data. Weighted mean differences
(WMD, 95% CI) were calculated for continuous data when
similar metrics were used across the reported outcomes. Heter-
ogeneity was explored through the Q-statistic and by calculating
the I
2
. Summary ORs and WMDs were calculated using the
random effects model to provide a conservative analysis in the
case of heterogeneity. When statistical heterogeneity was high
(I
2
50%), reasons for heterogeneity were explored. When
possible, data were analyzed by intention-to-treat approach.
When dropouts from the clinical trials were unaccounted for, we
planned to do worst-case scenario sensitivity analyses to deter-
mine whether the conclusions were robust. Meta-regression was
performed to assess the relationship between effect size and
length of follow-up. Statistical significance for overall effect was
defined as P 0.05 or a confidence that excluded the value 1.00
for ORs and 0 for WMDs.
RESULTS
Study Identification
Of 4303 citations screened, 475 were identified as
potentially relevant and were retrieved for review. Of these,
33 met the inclusion criteria for the primary analysis of
surgical AF ablation (10 RCTs including a total 650 pa-
tients
11–21
and 23 non-RCTs of 2997 patients,
22– 46
for an
overall total of 4647 patients; Fig. 1, QUOROM Flowchart).
For trials that reported more than once on an identical or
overlapping population, only the most recent or most com-
plete results were included. Some non-RCTs may have ex-
cluded patients with early complications or if ablative surgery
was aborted, and in many non-RCTs, patient attrition was
inadequately described. Publication bias was not evident after
visual inspection of funnel plots; however, this test was
underpowered for most clinical outcomes.
Patient Characteristics
Baseline characteristics are listed in Table 2. At base-
line, the mean age was 65 years, and 50% were male.
FIGURE 1. QUOROM flowchart.
TABLE 2. Baseline Characteristics for Included Patients
Baseline
Surgical Ablation
Mean (%)
Control
Mean (%) P
Male 49.6 51.5 0.18
RCT 50.2 48.5
Non-RCT 49.2 51.9
Permanent/persistent AF 87.5 84.7 0.25
RCT 48 80
Non-RCT 87.9 84.7
Paroxysmal AF 14.5 15.5 0.25
RCT 12.5 15.3
Non-RCT 50 20
NYHA III–IV 53.4 69.6 0.32
RCT 71.6 74.3
Non-RCT 49.7 67.8
Age (yr), mean (SD) 0.1 (1.2 to 1.4) 0.85
RCT 0.9 (1.2 to 1.4)
Non-RCT 0.48 (2.2 to 1.3)
AF duration (yr) 0.8 (1.8 to 0.2) 0.10
RCT 1.7 (8.5 to 5.1)
Non-RCT 0.8 (1.8 to 0.2)
LVEF (%) 1.0 (2.3 to 0.4) 0.16
RCT 1.1 (3.0 to 0.8)
Non-RCT 0.8 (2.7 to 1.1)
NYHA, class (RCT only) 0.13 (0.6 to 0.3) 0.58
Cheng et al Innovations Volume 5, Number 2, March/April 2010
Copyright © 2010 by the International Society for Minimally Invasive Cardiothoracic Surgery86
Although baseline patient characteristics were similar for
RCT and non-RCT, the small size of the RCT and the
inconsistent reporting of baseline characteristics in non-RCT
precluded adequate power to rule out potential differences.
More than 85% of patients had permanent or persistent AF,
and 15% had paroxysmal AF.
Heterogeneity
Significant heterogeneity across studies was ob-
served for achievement of sinus rhythm, cardioversion,
cardiac death, continuation of antiarrhythmics, duration of
surgery, and length of stay. Nevertheless, for most of these
outcomes, the heterogeneity was less concerning because it
was driven by uncertainty about the size of effect and not
the direction of effect and, therefore, did not generally put
into question the presence of significant benefit (when
detected), with the exception of antiarrhythmics, cardiac
death, and cardioversion.
Sinus Rhythm
The number of patients discharged from hospital in
sinus rhythm was significantly higher for the surgical AF
ablation group (68.6%) versus the non-AF ablation group
(23.0%) in RCTs (OR 010.1, 95% CI 4.5–22.5, 8 RCTs) and
non-RCTs (OR 7.15, 95% CI 3.42–14.95, 12 non-RCTs; Fig.
2A). This significant effect on sinus rhythm was maintained
at 1 year in RCTs (OR 10.9, 95% CI 5.4 –22.1, 8 RCTs) and
in non-RCTs (OR 9.53, 95% CI 5.5–16.6, 10 non-RCTs). In
trials that reported longer term results (1–5 years), there were
significantly more patients in sinus rhythm in the ablation
group (74.6% vs. 18.4%; OR 6.7, 95% CI 2.8–15.7; 1 RCT
and OR 15.5, 95% CI 6.6 –36.7, 10 non-RCTs; Fig. 2B). The
number of patients undergoing direct current cardioversion
was not different between the groups (Table 3).
Antiarrhythmics and Pacemakers
There was significant heterogeneity in the trials regard-
ing the continuation of antiarrhythmics post-AF ablation.
Some trials reported routine long-term continuation regard-
less of achievement of sinus rhythm, whereas other studies
did not report information on local policies regarding antiar-
rhythmic continuation. Although antiarrhythmic drug use was
not significantly reduced in the surgical AF ablation group
versus nonablation group in RCTs (OR 0.96, 95% CI 0.33–
2.82; 5 RCTs), there was significant reduction in antiarrhyth-
mic drug use in non-RCTs (OR 0.17, 0.07– 0.37). However,
the majority of the heterogeneity was driven by two RCTs in
which policies specified that antiarrhythmics should be rou-
tinely continued.
The number of patients with AV block was not signif-
icantly different between groups in RCT (OR 0.98, 95% CI
0.20 4.91; 2 RCTs) and non-RCT studies (OR 2.39, 95% CI
0.67– 8.52; 3 non-RCTs). The number of patients requiring a
temporary pacemaker did not differ between the groups.
Similarly, the number of patients requiring permanent pace-
maker insertion was not different in RCT (OR 1.2, 95% CI
0.5–2.6; 7 RCTs) or in non-RCT studies (OR 1.9, 95% CI
0.9 –3.7; 11 non-RCTs; Fig. 3).
Death
The risk of 30-day all-cause mortality was not different
between the groups in RCT (OR 1.20, 95% CI 0.52–3.16; 7
RCTs) or non-RCT studies (OR 0.99, 95% CI 0.52–1.87; 12
non-RCTs). All-cause mortality was not significantly differ-
ent at 1 year in RCT (OR 1.07, 95% CI 0.47–2.43; 7 RCTs)
or non-RCT studies (OR 1.04, 95% CI 0.45–2.43; 5 non-
RCTs; Fig. 4A). In studies reporting all-cause mortality at 2
years or more (up to 5 years), all-cause mortality did not
differ in RCT studies (OR 1.92, 95% CI 0.41–9.04; 8 RCTs)
but was significantly reduced after surgical ablation of AF in
non-RCT studies (OR 0.41, 95% CI 0.21– 0.79; 10 non-
RCTs; Fig. 4B). The risk of cardiac death was similar
between the groups in RCT and non-RCT studies.
Stroke and Thromboembolic Events
The risk of stroke or TIA in hospital did not differ
between the groups for RCT (OR 0.71, 95% CI 0.06 8.36; 2
RCTs) or non-RCT studies (OR 0.68, 95% CI 0.15–2.98; 2
non-RCTs). When all trials reporting stroke at follow-up
were considered, there was no significant difference between
the groups for RCT studies (OR 0.92, 95% CI 0.20 4.32; 4
RCTs); however, there was a significant reduction in the risk
of stroke or TIA in favor of ablation in non-RCT studies (OR
0.25, 95% CI 0.14 0.46; 10 RCTs). When stroke or throm-
boembolic events were considered in aggregate, the differ-
ence between groups did not reach significance for RCT
studies (OR 0.35, 95% CI 0.09–1.32, 5 RCTs), but it reached
significance for non-RCT studies (OR 0.28, 95% CI 0.15–
0.52; 10 non-RCTs) in favor of ablation (Fig. 5A).
Length of Follow-Up and Effect on Stroke
When meta-regression revealed a statistically signifi-
cant relationship between stroke reduction and time since
surgery, it suggests that surgical AF ablation provided in-
creasing protection from stroke with increased follow-up
(P 0.03; Fig. 5B). Similarly, for the aggregate of stroke or
thromboembolic events, surgical AF ablation provided sig-
nificantly greater protection as the length of follow-up in-
creased (P 0.007).
Other Clinical Outcomes
The risk of myocardial infarction, low cardiac output
syndrome, intraaortic balloon pump, bleeding events, cardiac
tamponade, reintervention for valvular leak or regurgitation,
renal dysfunction, and congestive heart failure did not differ
between groups for RCT or non-RCT studies. Although
reoperation for bleeding did not differ in RCTs (OR 0.61,
95% CI 0.19 –1.92; 4 RCTs), there was a significant increase
in risk of reoperation for bleeding after ablation of AF in
non-RCT studies (OR 2.63, 95% CI 1.11–6.22; 7 non-RCTs).
Patient Functionality Outcomes and QOL
Left ventricular ejection fraction was significantly im-
proved after ablation of AF in RCT studies (WMD 4%, 95%
CI 1%–2%, 3 RCTs) but not in non-RCT studies (WMD 2,
95% CI 1% to 5%; 2 non-RCTs). The number of patients
remaining in NYHA classes III to IV was not different
between the groups in RCT or non-RCT studies.
Innovations Volume 5, Number 2, March/April 2010 Surgical Ablation for Atrial Fibrillation Review
Copyright © 2010 by the International Society for Minimally Invasive Cardiothoracic Surgery 87
Exercise testing was performed in two RCTs. De Lima
et al
14
reported that the chronotropic response was signifi-
cantly better in the surgical ablation group (pulmonary vein
isolation [PVI] or maze) compared with control (86.2% or
80.5% for ablation vs. 64.1% for control, P 0.05); how-
ever, in this study, only NSR patients underwent testing.
Deneke et al
15
reported that although VO
2
max was not
different between groups, the maximum workload was in-
FIGURE 2. A, NSR, at discharge: surgery ablation vs. surgery alone. B, NSR, at 1 to 5 years: surgery ablation vs. surgery
alone.
Cheng et al Innovations Volume 5, Number 2, March/April 2010
Copyright © 2010 by the International Society for Minimally Invasive Cardiothoracic Surgery88
TABLE 3. Clinical Outcomes
Design AF Ablation Control I
2
(%)
OR P
SR postoperative All 73.9 33.2 79 8.4 (5.2–13.6) 0.0001
RCT 62.5 44.9 72 3.1 (1.2–8.0) 0.02
Non-RCT 78.6 29.6 60 11.8 (6.7–20.6) 0.0001
SR, at D/C All 68.6 23.0 72 8.4 (4.9–14.4) 0.0001
RCT 59.3 14.3 61 10.1 (4.5–22.5) 0.0001
Non-RCT 72.7 26.9 78 7.2 (3.4–14.9) 0.0001
SR, 3–6 mo All 70.3 24.1 56 11.2 (7.5–16.7) 0.0001
RCT 63.0 23.0 53 6.7 (3.6–12.6) 0.0001
Non-RCT 81.8 25.1 8 15.9 (9.5–26.5) 0.0001
SR, 1 yr All 75.0 22.6 71 10.9 (7.4–16.0) 0.0001
RCT 70.0 23.0 61 9.6 (5.6–16.4) 0.0001
Non-RCT 77.2 22.3 34 12.4 (7.2–21.5) 0.0001
SR, at latest follow-up (1 yr) All 74.6 18.4 84 10.2 (5.5–18.7) 0.0001
RCT 62.5 20.0 0 6.7 (2.8–15.7) 0.0001
Non-RCT 76.6 18.3 85 15.5 (6.6–36.7) 0.0001
Antiarrhythmics at follow-up All 31.7 65.0 82 0.31 (0.16–0.60) 0.0004
RCT 43.9 39.3 63 0.96 (0.33–2.82) 0.94
Non-RCT 28.5 72.9 73 0.17 (0.07–0.37) 0.0001
AV block All 3.7 2.7 10 1.69 (0.62–4.60) 0.30
RCT 4.4 4.3 0 0.98 (0.20–4.91) 0.98
Non-RCT 3.5 2.0 15 2.39 (0.67–8.52) 0.18
DC cardioversion All 32.5 35.9 69 0.97 (0.43–2.19) 0.94
RCT 25.0 25.0 0 1.33 (0.35–5.13) 0.68
Non-RCT 33.1 37.5 74 0.80 (0.29–2.24) 0.67
Pacemaker, temporary All 9.8 9.3 0 1.22 (0.56–2.66) 0.61
RCT 5.9 9.5 0 1.21 (0.41–3.57) 0.73
Non-RCT 18.3 9.2 0 1.24 (0.41–3.79) 0.70
Pacemaker, permanent All 5.0 4.0 0 1.53 (0.90–2.60) 0.12
RCT 4.4 4.9 0 1.15 (0.50–2.64) 0.73
Non-RCT 5.2 3.7 9 1.85 (0.93–3.70) 0.08
Death, inhospital All 2.8 2.9 0 1.05 (0.61–1.79) 0.86
RCT 3.7 2.8 0 1.20 (0.45–3.16) 0.72
Non-RCT 2.4 2.9 0 0.99 (0.52–1.87) 0.97
Death, 1 yr All 5.7 5.0 0 1.06 (0.59–1.90) 0.86
RCT 6.9 6.2 0 1.07 (0.47–2.43) 0.88
Non-RCT 4.9 4.0 0 1.04 (0.45–2.43) 0.92
Death, 2–5 yr All 6.4 17.9 46 0.52 (0.28–0.96) 0.04
RCT 9.2 5.0 0 1.92 (0.41–9.04) 0.41
Non-RCT 5.6 19.6 33 0.41 (0.21–0.79) 0.008
Death at latest follow-up (1–5 yr) All 6.1 11.1 23 0.74 (0.47–1.15) 0.18
RCT 7.7 6.0 0 1.21 (0.59–2.51) 0.60
Non-RCT 5.4 13.4 29 0.54 (0.31–0.96) 0.04
Cardiac death All 2.2 9.6 62 0.45 (0.12–1.65) 0.23
RCT 0.8 2.6 0 0.54 (0.11–2.72) 0.45
Non-RCT 2.8 12.1 76 0.33 (0.04–2.87) 0.32
Stroke or TIA All 2.3 5.3 34 0.30 (0.17–0.52) 0.0001
RCT 5.5 4.9 33 0.92 (0.20–4.32) 0.91
Non-RCT 1.8 5.3 0 0.25 (0.14–0.46) 0.0001
Cardiac tamponade All 0.6 4.2 0 0.28 (0.05–1.49) 0.13
RCT 1.5 4.3 0 0.43 (0.06–3.04) 0.40
Non-RCT 0 3.7 0 0.28 (0.05–1.49) 0.13
Reoperation for bleeding All 5.1 3.6 10 1.55 (0.78–3.09) 0.21
RCT 2.9 5.0 0 0.61 (0.19–1.92) 0.40
Non-RCT 6.6 3.5 2 2.63 (1.11–6.22) 0.03
(Continued)
Innovations Volume 5, Number 2, March/April 2010 Surgical Ablation for Atrial Fibrillation Review
Copyright © 2010 by the International Society for Minimally Invasive Cardiothoracic Surgery 89
creased for maze versus control in 22 patients (P 0.008).
Doukas et al
16
reported that patients undergoing surgical
ablation recorded longer distances than control patients on the
shuttle walk test (P 0.02); although, when the increase in
distance over baseline was compared, the significance did not
remain (P 0.13).
QOL was reported in two RCTs. Jessurun et al
18
reported no significant difference between surgical AF
ablation and control patients on Short Form-36 domains at
3 months and 12 months. Similarly, von Oppell
21
found
that Short Form-36 scores generally did not differ between
the groups.
Resource-Related Outcomes
Cardiopulmonary bypass time was significantly greater
by a mean of 27 to 55 minutes in the surgical AF ablation
group compared with surgery alone in the RCT (WMD 27
minutes, 95% CI 5–16 minutes; 8 RCTs) and in the non-RCT
studies (WMD 55 minutes, 95% CI 6 43 minutes; 13 non-
RCTs). Cross-clamp time was also significantly greater by a
mean of 15 to 41 minutes in RCT (WMD 15 minutes, 95% CI
4 –7 minutes; 6 RCTs) and in non-RCT studies (WMD 41
minutes, 95% CI 5–30 minutes; 11 non-RCTs). Operation
time was significantly greater for surgical AF ablation in
non-RCT (WMD 166 minutes, 95% CI 14 –139 minutes; 2
non-RCTs) but not in the sole RCT reporting this outcome
(WMD 7 minutes, 95% CI 4 to 18 minutes; 1 RCT). Length
of stay in ICU was not reduced significantly in the sole RCT
reporting this outcome (WMD 0.5, 95% CI 1.5 to 0.5; 1
RCT) and was significantly increased in non-RCT studies
(WMD 0.9 days, 95% CI 0.3–1.6 days; 4 non-RCTs). Total
hospital length of stay was not significantly different between
groups in RCT studies (WMD 0.7 days, 95% CI 0.8 to 2.2
days, 5 RCTs) but was significantly increased after ablation
of AF in non-RCT studies (WMD 1.5 days, 95% CI 0.6 –2.3,
5 non-RCT studies; Table 4).
Subanalyses by Type of Procedure or Modality
Subanalyses by type of procedure (cut-and-sew vs.
energy ablation) did not show significant differences for
success with different procedures (ie, the relative odds for
achievement of sinus rhythm for surgical ablation over no
ablation was similar across different modalities of ablation).
There was insufficient information to evaluate differences by
pulmonary vein isolation versus biatrial versus single atrial
procedures.
TABLE 3. (Continued)
Design AF Ablation Control I
2
(%)
OR P
Reintervention for valvular leak or regurgitation All 2.8 2.0 0 1.70 (0.56–5.17) 0.35
RCT 3.7 1.2 0 2.14 (0.27–17.0) 0.47
Non-RCT 2.5 2.3 0 1.55 (0.42–5.78) 0.51
Mediastinitis All 0.3 1.8 0 1.78 (0.53–6.01) 0.34
RCT 3.1 0 0 2.82 (0.32–24.9) 0.35
Non-RCT 2.0 1.9 0 1.45 (0.34–6.27) 0.62
Thromboembolic events All 0.5 7.0 0 0.21 (0.05–0.94) 0.04
RCT 0 5.9 0 0.19 (0.01–4.20) 0.30
Non-RCT 0.7 7.3 6 0.22 (0.04–1.19) 0.08
Myocardial infarction All 1.9 1.1 0 1.78 (0.68–4.68) 0.24
RCT 3.4 2.2 0 1.13 (0.13–9.58) 0.91
Non-RCT 0.4 1.0 0 2.00 (0.68–5.92) 0.21
Low cardiac output syndrome All 9.3 6.6 0 1.56 (0.79–3.08) 0.20
RCT 10.8 8.1 0 1.85 (0.79–4.30) 0.15
Non-RCT 6.4 5.1 0 1.15 (0.36–3.60) 0.81
Intraaortic balloon pump All 8.0 3.2 0 1.98 (0.90–4.37) 0.09
RCT 8.8 0 0 7.89 (0.39–158) 0.18
Non-RCT 7.8 3.3 0 1.79 (0.79–4.06) 0.16
Congestive heart failure All 1.4 6.8 0 0.27 (0.04–1.69) 0.16
RCT 2.9 8.6 0 0.32 (0.03–3.27) 0.34
Non-RCT 0 5.1 0 0.19 (0.01–4.09) 0.29
Renal dysfunction All 3.3 5.9 0 0.57 (0.20–1.58) 0.28
RCT 6.1 12.5 0 0.46 (0.11–1.94) 0.29
Non-RCT 2.3 5.7 0 0.71 (0.17–3.03) 0.64
Pneumonia or pleural effusion All 5.2 5.1 0 1.19 (0.50–2.85) 0.70
RCT 9.6 8.1 0 1.13 (0.44–2.91) 0.80
Non-RCT 1.4 0 0 1.57 (0.16–15.44) 0.70
NYHA III–IV at follow-up All 24.5 49.6 74 0.63 (0.25–1.57) 0.32
RCT 8.3 12 0 0.67 (0.10–4.39) 0.67
Non-RCT 25.5 53.9 79 0.62 (0.22–1.77) 0.37
SR, sinus rhythm.
Cheng et al Innovations Volume 5, Number 2, March/April 2010
Copyright © 2010 by the International Society for Minimally Invasive Cardiothoracic Surgery90
DISCUSSION
Overall, this meta-analysis suggests that surgical AF
ablation results in better rates of sinus rhythm both early and
late (1 year) after surgery compared with patients not
having surgical ablation. The results obtained from the RCT
and non-RCT studies are largely congruent with each other
regarding the increase in number of patients achieving sinus
rhythm with surgical ablation. More than 70% of patients in
the surgical ablation group were in sinus rhythm at 1 year,
compared with 20% in the surgery only group. Although
statistically significant heterogeneity was found, this hetero-
geneity was because of the magnitude of reduction varying
across trials and was not because of differences in direction of
effect across studies (all studies showed improved likelihood
of achieving sinus rhythm after surgical ablation of AF, with
ORs ranging from 3 to 77).
Whether surgical AF ablation allows more patients to
discontinue antiarrhythmics remains uncertain because of the
relatively few trials that reported this outcome and because of
the heterogeneity across trials in reporting us of antiarrhyth-
mic drugs. Some studies reported antiarrhythmics by class,
whereas others reported antiarrhythmics and rate control
drugs only in aggregate. Also, some studies routinely contin-
ued rhythm and rate control drugs in patients regardless of
achievement of sinus rhythm, whereas other studies left the
decisions to the discretion of prescribers. It is important to
note that none of the trials included in this meta-analysis were
prospectively powered to measure the ability to discontinue
antiarrhythmics and rate control drugs. Although there was
significant reduction in the use of antiarrhythmics in non-
RCTs, this was not true for RCTs. However, the latter
included two RCTs, which specified that antiarrhythmics
should be continued postprocedure regardless of rhythm.
Similarly, for oral anticoagulants (not assessed in this meta-
analysis), there was inconsistent reporting of policies and
prescribing patterns for patients who achieved sinus rhythm
postprocedure.
Permanent pacemaker insertion was also heterogeneous
across trials, and although there was no difference in RCTs,
there was a trend toward increased incidence of pacemaker
insertion in the surgical AF ablation group in non-RCT
studies. This raises concern about the risk of iatrogenically
induced bradycardia or other arrhythmias during or after AF
ablation. Because of the long-term implications, heteroge-
neous data, and relatively few RCTs reporting this outcome,
further study will be necessary to better characterize whether
pacemaker insertion is truly an increased risk with surgical
ablation (and, if so, whether it is associated with different
techniques used to surgically ablate AF such as with pulmo-
nary vein isolation, with cut-and-sew, or with certain map-
ping techniques). Retrospective evaluation of multicenter
experience in the United States from the Society of Thoracic
Surgeons database suggests that the risk of pacemaker inser-
tion is significantly increased with surgical AF ablation com-
pared with surgery alone.
47
Overall, mortality was not affected by applying surgical
ablation when compared with the nonablation group both for
the RCT and non-RCTs up to 1 year. However, it is notable
that all-cause mortality was significantly lower in the surgical
ablation groups in the non-RCTs with longer term follow-up
(mean all-cause mortality was 5.4% vs. 13.4% in the ablation
vs. control groups at midterm follow-up of 1–5 years).
Stroke and TIAs were also reduced after surgical abla-
tion of AF in non-RCT studies but not in RCTs. However,
FIGURE 3. Permanent pacemaker, at discharge: surgery ablation vs. surgery alone.
Innovations Volume 5, Number 2, March/April 2010 Surgical Ablation for Atrial Fibrillation Review
Copyright © 2010 by the International Society for Minimally Invasive Cardiothoracic Surgery 91
only two RCTs reported strokes. When all studies were
analyzed by length of follow-up, the strength of association
magnitude of stroke reduction in the surgical AF ablation
group improved over time compared with the control group,
suggesting that there is greater reduction in stroke with longer
term follow-up. Similarly, for stroke and thromboembolic
events considered in aggregate, there was a significant reduc-
tion in the surgical AF ablation group, and this effect was
strengthened with longer term follow-up.
Other outcomes, including NYHA class, ejection
fraction, exercise testing, and QOL scores were not sig-
nificantly impacted by surgical AF ablation; however,
these outcomes were poorly reported, and in general, the
direction of effect showed a trend toward a benefit in favor
of ablation.
As expected, cross-clamp times and operation time
were significantly increased with surgical AF ablation.
However, there was significant heterogeneity across trials
as varied levels of experience and techniques were used.
The increase in cross-clamp and procedure times is diffi-
cult to generalize to other settings but should be consid-
ered before adopting the procedure for routine practice.
Overall impact on costs and length of stay remains largely
unstudied. Non-RCT studies suggested that hospital length
FIGURE 4. A, Death, at 1 year: surgery ablation vs. surgery alone. B, Death, at 2 to 5 years: surgery ablation vs. surgery
alone.
Cheng et al Innovations Volume 5, Number 2, March/April 2010
Copyright © 2010 by the International Society for Minimally Invasive Cardiothoracic Surgery92
of stay may be increased with surgical AF ablation; how-
ever, RCTs did not show a significant difference. It is
important to note that some of the non-RCTs included
early operator experience and some included more com-
plex cut-and-sew patterns.
Strengths and Limitations
This meta-analysis provides a comprehensive system-
atic review of all available comparative studies of surgical AF
ablation for patients undergoing cardiac surgery. To date, few
meta-analyses have been done to address this question, and
the surgeons and their patients have had to make decisions
without a clear understanding of the evidence base. This
evidence base should be interpreted in light of the remaining
uncertainties.
A number of limitations should be highlighted to facil-
itate appropriate interpretation of this meta-analysis. First and
foremost, some of the data come from non-RCT studies,
which may be susceptible to bias in patient selection and
incomplete ascertainment of outcomes. As a result, RCT data
should be preferred to the non-RCT data whenever possible
in this analysis. However, the RCTs reported a narrower
range of outcomes, on a smaller number of patients, and were
FIGURE 5. A, Stroke or thromboembolic events at latest follow-up: ablation surgery vs. surgery alone. B, Length on fol-
low-up in year on risk of stroke.
Innovations Volume 5, Number 2, March/April 2010 Surgical Ablation for Atrial Fibrillation Review
Copyright © 2010 by the International Society for Minimally Invasive Cardiothoracic Surgery 93
generally of shorter follow-up than the collective evidence
available in the non-RCT studies. As a result, the non-RCT
data adds information regarding a broader range of outcomes,
including adverse effects, and over a longer follow-up.
Additional limitations include the wide range of dates
of the included studies and the presumed range of surgeon
expertise represented. The included trials were published in
the years ranging from 1996 to 2009. The surgeons’ level of
expertise was rarely specified in the included trials and leaves
the reader with uncertainty whether the results will apply
equally to contemporary situations, with newer technologies,
and an overall increasing expertise in the techniques of
surgical ablation. Furthermore, the role of appendage exclu-
sion, per se, is often incompletely reported.
Clinical Implications
This analysis confirms the potential role of surgical AF
ablation for achievement of sinus rhythm. It suggests that
surgical ablation should be discussed as an option for patients
with AF who present for cardiac surgery. Whether the pro-
cedure will allow them to discontinue antiarrhythmics, rate
control drugs, or anticoagulation over the longer term re-
mains unproven, although the potential exists. Discussing the
possibility of reduced stroke and thromboembolic events over
the longer term, but potential increased need for pacemaker
insertion, will also be key in the discussions with patients to
allow for informed decision making.
Which Ablative Technique Is Best?
Unfortunately, this analysis did not allow for statistical
differentiation in outcomes among the various ablative tech-
niques used. Through subgroup analysis, we tested indirectly
whether one technique is better than another for achieving
sinus rhythm or for survival; however, the subgroups were
underpowered to adequately test the various techniques used
because there were few techniques that were similar enough
to be combined into subgroups. Future systematic reviews are
encouraged to compare head-to-head trials of ablative tech-
niques and technologies. To date, no single technique or
ablative technology can be definitively recommended over
another on the basis of comparative trials.
What This Study Adds to Current Literature
This review provides important information regarding
the potential for protection from stroke and thromboembolic
events over the longer term and, also, raises the issue of
potential for increased need for pacemaker insertion with
surgical AF ablation. This current systematic review repre-
sents an update of the earlier analysis also allows for com-
parison of RCT and non-RCT data.
Further Research Required
Examination of the limitations of this meta-analysis
highlights the need to address the deficiencies inherent in the
evidence base for surgical AF ablation. This meta-analysis
aggregates the best available evidence, but it does not obviate
the need for further RCTs; rather, this meta-analysis high-
lights the need for future RCTs of adequate power to measure
important differences in survival, stroke, thromboembolic
events, and patient symptoms and QOL. Cost-effectiveness
analyses alongside long-term RCTs should be performed to
inform future policies in this area as AF ablation increases
TABLE 4. Functional Clinical Outcomes and Resource-Related Outcomes
Outcome Design n
Weighted Mean
Difference P
LVEF (%), postoperative Non-RCT 38 7 (3to17) 0.17
LVEF last follow-up (%) All 67 1 (6to3) 0.19
RCT 4 (2 to 7) 0.001
Non-RCT 2(5 to 0.5) 0.11
NYHA latest follow-up All 82 0.4 (0.7 to 0.1) 0.02
RCT 0 0.4 (1to0.2) 0.18
Non-RCT 88 0.3 (0.7 to 0.03) 0.08
CPB time (min) All 93 39 (32 to 47) 0.0001
RCT 70 27 (16 to 37) 0.0001
Non-RCT 95 55 (43 to 67) 0.0001
Cross-clamp time (min) All 94 25 (18 to 31) 0.0001
RCT 62 15 (7 to 23) 0.0001
Non-RCT 96 41 (30 to 52) 0.0001
Operation time (min) All 98 29 (19 to 40) 0.0001
RCT 0 7 (4 to 18) 0.29
Non-RCT 4 166 (138 to 193) 0.00001
ICU length of stay (d) All 69 0.5 (0.1 to 1.1) 0.07
RCT 0 0.5 (1.5 to 0.5) 0.33
Non-RCT 34 1 (0.3 to 1.6) 0.005
Hospital length of stay (d) All 0 1.3 (0.5 to 2.0) 0.0008
RCT 0 0.7 (0.8 to 2.2) 0.35
Non-RCT 3 1.5 (0.6 to 2.3) 0.0008
LVEF, left ventricular ejection fraction; CPB, cardiopulmonary bypass.
Cheng et al Innovations Volume 5, Number 2, March/April 2010
Copyright © 2010 by the International Society for Minimally Invasive Cardiothoracic Surgery94
operating time but may prevent future adverse events related
to stroke and thromboembolism.
CONCLUSIONS
Evidence to date suggests that surgical AF ablation
significantly improves the odds of achieving sinus rhythm by
more than 10-fold and this improvement is retained beyond 1
year when compared with cardiac surgery without ablation in
patients with persistent or permanent AF who present for
valvular and/or coronary artery bypass surgery. Non-RCT
evidence suggests that surgical AF ablation may also reduce
the risk of stroke and thromboembolic events but may in-
crease need for pacemaker insertion. Longer term follow-up
from existing and future RCTs should be encouraged to
ascertain whether this reduction in stroke is a robust finding
and over what time course antiarrhythmics can be safely
discontinued. Finally, prospective, RCT studies are urgently
needed to better define the best lesion sets to be used in each
particular patient population and to help determine the supe-
rior ablation technologies.
ACKNOWLEDGMENTS
The authors thank Ms. Aurelie Alger and Ms. Elizabeth
Chouinard for their professional assistance in organizing the
consensus conference; Dr. Kathy Fang and Dr. Myoung Kim
for data extraction and verification; and Jennifer Podeszwa
DeOliveira and Erin Boyce for facilitating literature searches
and retrieval.
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Cheng et al Innovations Volume 5, Number 2, March/April 2010
Copyright © 2010 by the International Society for Minimally Invasive Cardiothoracic Surgery96
    • "In a meta-analysis of randomized studies, Phan et al. concluded no significant difference in rate of neurological events [24]. In larger systematic review and meta-analysis of both randomized and non-randomized studies, Cheng et al. found out that stroke incidence was not reduced significantly; however, in meta-regression, the risk of stroke decreased significantly with longer follow-up [15]. Whether this reduced risk of stroke is related to resumption of sinus rhythm and atrial systole or due to closure or removal of the LAA or continued use of warfarin in some of patients is not certain. "
    [Show abstract] [Hide abstract] ABSTRACT: Atrial fibrillation (AF) is the most frequent cause of stroke. Surgical ablation of AF presents a rapidly evolving area in cardiac surgery. Concomitant procedures and operations for stand-alone AF have been considered safe and effective in sinus rhythm restoration. Their clinical effect in stroke prevention, as well as the effect of elimination of the left atrial appendage, is less clear. In this article we summarize current cardiac surgery procedures for AF treatment and LAA elimination with special regard to their efficacy in stroke prevention.
    Full-text · Article · Feb 2016
    • "In meta-regression analysis the risk of stroke decreased significantly with longer follow-up time. Although the ablative procedure increased operating time, it did not have a significant effect on peri-operative all-cause mortality or hospital length of stay [70]. Since around 90% of the thrombi that cause stroke in AF form in the left atrial appendage (LAA) [71], successful closure of the appendage may also reduce the risk of neurological injury. "
    [Show abstract] [Hide abstract] ABSTRACT: Cardiac surgery is increasingly performed in elderly patients, and whilst the incidence of common risk factors associated with poorer outcome increases with age, recent studies suggest that outcomes in this population may be better than is widely appreciated. As such, in this review we have examined the current evidence for common cardiac surgical procedures in patients aged over 70 years. Coronary artery bypass grafting (CABG) in the elderly has similar early safety to percutaneous intervention, though repeat revascularisation is lower. Totally avoiding instrumentation of the ascending aorta with off-pump techniques may also reduce the incidence of neurological injury. Aortic valve replacement (AVR) significantly improves quality of life and provides excellent short- and long-term outcomes. Combined AVR and CABG carries higher risk but late survival is still excellent. Mini-sternotomy AVR in the elderly can provide comparable survival to full-sternotomy AVR. More accurate risk stratification systems are needed to appropriately select patients for transcatheter aortic valve implantation. Mitral valve repair is superior to replacement in the elderly, although choosing the most effective method is important for achieving maximal quality of life. Minimally-invasive mitral valve surgery in the elderly has similar postoperative outcomes to sternotomy-based surgery, but reduces hospital length of stay and return to activity. In operative candidates, surgical repair is superior to percutaneous repair. Current evidence indicates that advanced age alone is not a predictor of mortality or morbidity in cardiac surgery. Thus surgery should not be overlooked or denied to the elderly solely on the basis of their "chronological age", without considering the patient's true "biological age".
    Full-text · Article · Apr 2014
    • "The clinical advent of linear ablation lines generalized this technically challenging procedure throughout cardiac surgery with preserved clinical efficacy [32, 33]. A recent meta-analysis (N=4647: 10 randomized trials; 23 non-randomized control studies) demonstrated that AF ablation during concomitant cardiac surgery significantly increased the likelihood of durable sinus rhythm (odds ratio 10.1; 95% confidence interval 4.5-22.5 for randomized studies) [34]. "
    [Show abstract] [Hide abstract] ABSTRACT: There has been significant progress throughout 2013 in cardiothoracic and vascular anaesthesia and intensive care. There has been a revolution in the medical and interventional management of atrial fibrillation. The medical advances include robust clinical risk scoring systems, novel oral anticoagulants, and growing clinical experience with a new antiarrhythmic agent. The interventional advances include left atrial appendage occlusion for stroke reduction, generalization of ablation techniques in cardiac surgery, thoracoscopic ablation techniques, and the emergence of the hybrid ablation procedure. Recent European guidelines have defined the organization and practice of two subspecialties, namely general thoracic surgery and grown-up congenital heart disease. The pivotal role of an effective multidisciplinary milieu is a central theme in both these clinical arenas. The anaesthesia team features prominently in each of these recent guidelines aimed at harmonizing delivery of perioperative care for these patient cohorts across Europe. Web-Enabled Democracy-Based Consensus is a system that allows physicians worldwide to agree or disagree with statements and expert consensus meetings and has the potential to increase the understanding of global practice and to help clinicians better define research priorities. This "Democratic based medicine", firstly used to assess the interventions that might reduce perioperative mortality has been applied in 2013 to the setting of critically ill patient with acute kidney injury. These advances in 2013 will likely further improve perioperative outcomes for our patients.
    Full-text · Article · Mar 2014
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