Transcript An 8½ Year Clinical Experience with Surgery for Atrial Fibrillation

The Maze Procedure
in Mitral Vale Disease
Ki-Bong Kim, MD
Dept. of Thoracic & Cardiovascular Surgery
Seoul National University Hospital
Atrial Fibrillation


Prevalence :

0.15-1.0 % of general population

8-17 % of population > 60 yrs

70-80 % in pts w/ MV disease

40-60 % in pts undergoing surgery for Tx of MV disease
Incidence of asso. thromboembolism : 33 %


75 % of episodes can involve the brain
60 % of those events can result in death
or severe morbidity
Three Untoward Effects of AF



Unpleasantness of an irregular heart beat
Impaired hemodynamics because of the
loss of AV synchrony
Vulnerability to the thromboembolic
complications
The Cox-Maze III Procedure
 The extended op time needed for complicated
multiple atrial incisions may preclude application of
the CM-III as a concomitant op w/ standard OHS.
 We modified the CM-III to decrease op time, while
retaining the important principles of the maze
incisions.
Modification of the Cox-Maze III Procedure
Ki-Bong Kim, et al
Ann Thorac Surg 2001;71:816-22
Conventional CM-III
Modified CM-III
An 8½ -Year Clinical Experience
with Surgery for Atrial Fibrillation
Cox JL, et al
Ann Surg 1996;224:267-75
Methods
 Sept 1987 – March 1996
 164 pts between 3 mo & 8½ yrs after op
 CM-I ; 32 pts
 CM-II ; 14 pts
 CM-III ; 118 pts
 59 pts (33%) underwent concomitant op
in addition to the Maze procedure
Ann Surg 1996;224:267
Surgical Indications



Arrhythmia intolerance ; DOE, easy fatigability, lethargy,
malaise, general sense of impending doom during AF
Drug intolerance ; unsuccessful tx of max amount of
tolerable drug therapy
Previous TE ; significant temporary or permanent neurological
deficit
 Documented cerebral TE in the absence of other demonstrable
etiologies
 absolute Ix for surgery because anticoagulation does not
protect from a second stroke
Ann Surg 1996;224:267
Indications for Surgical Tx for AF
Indication
Arrhythmia Intolerance
n / Total
%
118 / 178
66
Drug Intolerance
16 / 178
9
Previous TE
44 / 178
25
Ann Surg 1996;224:267
Results
 93 % ; arrhythmia free w/o any antiarrhythmic
medication
 7 % ; converted to SR w/ medical tx
 Of the 107 pts who were documented to have
normal SA node pre-op, only 1 pt required a
permanent PM
Ann Surg 1996;224:267
Restoration of Atrial Transport Function
Following the MAZE procedure
Procedure
RA Function (+)
LA Function (+)
Maze-I
32/32 (100%)
23/32 (72%)
Maze-II
11/11 (100%)
7/11 (64%)
Maze -III
80/82 (98%)
77/82 (94%)
123/125 (98%)
107/125 (86%)
Total
Ann Surg 1996;224:267
Contraindications

Significant LV dysfunction, not attributable
to the arrhythmia itself

Concomitant cardiac / non-cardiac disease
that constitutes an excessive surgical risk

Pts w/ severe HOCM because of the excessive
risk asso. w/ the combined procedures
Ann Surg 1996;224:267
Restoration of Atrial Function After the
Maze Procedure for Patients with
Atrial Fibrillation ; Assessment by
Doppler Echocardiography
Feinberg MS, et al
Circulation 1994;5 (pt II):II-285-92
METHODS
 46 pts
 8 ± 7 mo after the Maze
 Additional procedures in 13 pts
Circulation 1994;5 (pt II):II-285
RESULTS

Restoration of RA contraction ; 83% (38/46)
LA contraction ; 61% (28/46)

% atrial filling fraction of RA in pts w/ active atrial
contraction was comparable to that of control (32±7 vs
33±8 %, p=NS), whereas that of LA was smaller (20±5
vs 36±7 %, p<0.05).
Circulation 1994;5 (pt II):II-285
The Outcome and Indications of
the Cox Maze III Procedure for Chronic Atrial
Fibrillation With Mitral Valve Disease
Isobe F, et al
J Thorac Cardiovasc Surg 1998;116:220-7
METHODS
 30/34 pts w/ AF + MV disease
 4 pts were excluded
 3 w/ incomplete cut & suture d/t severe
calcification & adhesions
 1 died of post LV rupture
 21 Rheumatic
8 Degenerative
1 PVF
JTCVS 1998;116:220
RESULTS
 F/U > 6 mo after the op (2.1±0.9 yrs)
 SR was restored in 27 pts (90%)
 RA contractility (+) in 100 % (27/27)
 LA contractility (+) in 67 % (18/27)
 AF persisted in 3 pts (10%)
JTCVS 1998;116:220
RESULTS (SR
group vs AF group)
 f-wave voltage in lead V1
 0.23±0.10
vs
0.06±0.05 mV
p=0.01
 CTR
 60±5
vs
78±10 %
p= 0.006
 LA systolic dimension (Doppler)
 57±8
vs
95±24 mm
p= 0.005
 AF duration
 5.1±4.6
vs 11.8±5.5 yrs
p= 0.049
» » Predisposing factors for the post-op
persistence of AF
JTCVS 1998;116:220
RESULTS

No pts resumed SR
when CTR ≥ 70 % &
LA systolic dimension ≥ 80 mm before the op
JTCVS 1998;116:220
RESULTS
 A/E ratio of trans-mitral flow was low in pts w/
the Maze procedure as compared w/ the normal valve
 Regarding the restoration of LA function,
f-wave voltage, CTR, & LA systolic dimension
showed no significant difference between the pts w/
positive & negative a-waves,
& only the duration of AF showed statistically
significant difference (p=0.011).
JTCVS 1998;116:220
Rationale of the Cox Maze Procedure for Atrial
Fibrillation During Redo Mitral Valve Operations
Kobayashi J, Kosakai Y, Isobe F, et al
J Thorac Cardiovasc Surg 1996;112:1216-22
METHODS

42 pts w/ redo MV + Maze procedure
 37 Kosakai’s modified Maze
 2 CM-II
 3 CM-III


F-U after op : 25.5 ± 10.8 mo.
Control group : 54 pts w/ redo MV
w/o Maze procedure
JTCVS 1996;112:1216
RESULTS

SR was regained in 28/42 pts (67 %)

Doppler study

LA contraction in 16/28 pts (57%)

RA contraction in 21/28 pts (75 %)
JTCVS 1996;112:1216
Comparison between pts w/
& w/o restored sinus rhythm
Variables
No.
Age (yr)
Rheumatic
SR (+)
SR(-)
p-value
28
14
57.8±10.0
56.1±9.3
NS
23(82%)
13(94%)
NS
Duration of AF (yr)
9.0±6.0
15.9±4.6
0.0009
f-wave on V1 (mV)
0.18±0.1
0.10±0.08
0.017
CT ratio (%)
63±8
67±5
0.049
LAD (mm)
57±9
57±6
NS
JTCVS 1996;112:1216
Results of op in the maze & control groups
Maze group
No.
Control group
p-value
42
54
ACC time (min)
133±28
121±44
0.048
CPB time (min)
211±43
197±78
0.012
C-tube drainage(ml)
890±510
840±480
NS
2140±1760
NS
Blood transfusion (ml) 2120±1600
# Transfusion
7(17%)
11(20%)
NS
Hospital Mortality
0(0%)
4(7.4%)
NS
Bleeding reop
6(14%)
4(7.4%)
NS
Mediastinitis
0(0%)
2(3.7%)
NS
JTCVS 1996;112:1216
CONCLUSION

The Maze procedure should be considered in selected pts who
have a high possibility of regaining SR during redo MV op.

The Maze procedure should be performed concomitantly w/
MVR while preserving the MV apparatus for moderately
depressed LV function, inasmuch as atrial contraction is very
important.
JTCVS 1996;112:1216
The Cox Maze III Procedure for Atrial Fibrillation
Associated With Rheumatic Mitral Valve Disease
Ki-Bong Kim, et al
Ann Thorac Surg 1999;68:799-804
METHODS

75 CM-III pts for AF asso w/ rheumatic
MV disease

14 cases ; Reop because of PVF
ANTS 1999;68:799
INDICATIONS

Indications to perform concomitant CM-III



Chronic AF >1 yr
LA thrombi (+)
Medical history of previous TE events in the
absence of other demonstrable etiologies
ANTS 1999;68:799
RESULTS

In-hospital Mortality ; 2.7% (2/75)

73 survivors were followed
for 30±13 mo (12-56)
ANTS 1999;68:799
Cardiac Rhythms in the Latest F-U
NSR


w/o drug therapy
w/ addition of one drug
AF
JR
PM implantation
66 / 73 (90 %)
60 (82 %)
6 (8 %)
3 / 73 (4 %)
2 / 73 (3 %)
2 / 73 (3 %)
ANTS 1999;68:799
Follow-Up TTE

66 pts w/ NSR

RA contractility (+) : 66 / 66 (100 %)
LA contractility (+) : 41 / 66 (62 %)*

Restoration of RA contractility : 69±93 days
Restoration of LA contractility :126±136 days*
* p < 0.05
ANTS 1999;68:799
Factors Predisposing to Persisting AF
Factors
NSR (n=66)
AF (n=3)
p-value
(univariate)
Age (>60 yrs)
13.6 %
33.3 %
ns
AF Duration (>60 Mo)
40.9 %
100.0 %
ns
LAD (>55 mm)
63.1 %
66.7 %
ns
LVEDD (>55 mm)
36.9 %
33.3 %
ns
EF (<45 %)
23.1 %
33.3 %
ns
Factors Affecting Recovery of LA Contractility
Factors
LA(+)
LA(-)
p-value
Univariate Multivariate
Age (<60 yrs)
Duration of AF (<60 mo)
87.5%
75.0%
92.3%
42.3%
NS
0.001
LAD (<55 mm)
41.0 %
38.5 %
NS
EF (>45 %)
74.4%
80.8%
NS
mPAP (<20 mmHg)
19.0%
14.3%
NS
C.I. (>2.0 L/min/m2)
72.4%
37.5%
NS
RA contractility (<60 d)
75.0%
37.5%
0.032
0.01
< 0.01
Non-redo vs. Redo OHS
Non-redo
AF duration (Mo)
Redo
p-value
52±57
132±91
<0.01
ACC time (min)
154±45
137±32
ns
CPB time (min)
250±69
258±95
ns
C-tube drain (ml)
985±669
822±261
ns
Bleeding reop
3
1
ns
Conversion rate (%)
90
92
ns
Conclusions

CM-III for AF asso w/ RMVD demonstrated a high
sinus conversion rate & recovery of atrial contractility

LA contractility is restored significantly later & a lower
rate than RA contractility in RMVD

CM-III can be performed in redo op w/ comparable
sinus conversion rate & acceptable op risk
ANTS 1999;68:799
Restoration of Atrial Mechanical Function After
Maze Operation in Patients With Structural
Heart Disease
Kim Y-J, Sohn D-W, et al
Am Heart J 1998;136:1070-4
METHODS



32 pts w/ the Maze procedure
SR was restored in 81 % (26/32)
 By surgery alone in 69 % (22/32)
 By the addition of one drug in 13% (4/32)
Of the remaining 6 pts,
 Four (13%, 4/32) pts ; paroxysmal AF despite
antiarrhythmic therapy
 One ; sustained AF
 One ; permanent PM insertion d/t SSS
Am Heart J 1998;136:1070
RESULTS

RA function (+) ; 30 / 30 pts w/ SR or
paroxysmal AF

LA function (+) ; 19 / 30 pts (63 %)
Am Heart J 1998;136:1070
RESULTS

Peak A velocity & A/E ratio of mitral inflow
in pts w/ restored LA function, were
significantly lower than in the 16 post-op
control pts (p<0.01).
Am Heart J 1998;136:1070
RESULTS

In pts w/ LA mechanical function, duration
of AF was significantly shorter than in pts
w/o LA mechanical function (1.9±2.9 vs
7.1±3.0 yrs, p<0.01), but there were no
significant differences in LA size & volume.
Am Heart J 1998;136:1070
Surgical Outcome of Maze Procedure for
Atrial Fibrillation in Mitral Valve Disease:
Rheumatic versus Degenerative
JW Lee,et al.
STS meeting, 2002

Group R (n=86) : Rheumatic

Group D (n=43) : Degenerative

Study interval : Immediate postop
3 Mo
6 Mo
Sinus Conversion Rate
(%)
100
90
80
70
60
50
40
30
20
10
0
86 89
94.1 95.3
95.3 97.7
72.1 69.8
P >0.05
immediate
P >0.05
7days
P >0.05
P >0.05
3months
6months
P < 0.05
Group R
GrooupD
Impact of the Maze Procedure on the Stroke
Rate in Patients with Atrial Fibrillation
Cox JL, et al
J Thorac Cardiovasc Surg 1999;118:833-40
Methods

Sept 1987 - March 1999

306 pts w/ the maze procedure
 paroxysmal (intermittent) AF ; 61 %

chronic (continuous) AF ; 39 %
JTCVS 1999;188:833
Peri-op Stroke Rates for the Major Categories of
Cardiac Surgical Procedures
Procedures
% permanent
stroke
% transient
stroke
% total
stroke
CABG + MVR
CABG + AVR
CABG + MV repair
AVR + MVR
MV repair
MVR
AVR
CABG
Maze ± other
4.17 %
3.40 %
3.12 %
2.73 %
1.85 %
2.28 %
1.73 %
1.69 %
0.65 %
1.73 %
1.60 %
1.41 %
1.51 %
1.45 %
0.98 %
1.23 %
0.75 %
0%
5.90 %
5.00 %
4.53 %
4.24 %
3.30 %
3.26 %
2.96 %
2.44 %
0.65 %
Whether should the pts w/o LA contractile
function after the maze undergo anticoagulation?

Normal RA function & normal RA-RV synchrony

Normal right-sided CO that is delivered to left side of heart
through pulmonary circulation

No difference whether LA is contracting (in the presence of
normal LV) because LV will immediately adapt to normal right-sided
output that has just been delivered to it

Normal LA inflow volume, regular LV filling, & no LAA to
serve as a nidus for thrombus formation

There is no reason to suspect that systemic TE would be
any higher in these pts than those w/ demonstrable LA contraction
JTCVS 1999;188:833
EPILOGUE
 When properly performed, the results w/ this
combined approach have been excellent,
w/ no increase in periop morbidity or op
mortality & w/ documented long-term
advantages over simply leaving pts in AF.
- James L. Cox
J Thorac Cardiovasc Surg 2001;122:212