A diifferent antegrad cardioplagia technique

1. Effect of Cardioplegic Infusion of
Antegrade Aortic Root and Bypass
Graft Combined With Passive Graft
Perfusion in On-Pump CABG
Tugrul Göncü1, Mustafa Günes1, Mustafa Sezen1, Hasan Ari2, Faruk
Toktas1, Ahmet Demir1, Osman Tiryakioglu1, Hakan Vural1, Senol
Yavuz1, Ahmet Ozyazicioglu1
1Department of cardiovascular Surgery, Bursa Yuksek Ihtisas
Education and Research Hospital, Bursa, Turkey

2. Introduction
• Coronary artery bypass grafting (CABG) performed with
the aid of cardioplegia and cardiopulmonary bypass
(CPB) requires a period of cardiac arrest.
• During this time, myocardial ischemia may occur, which
is an important determinant of functional and clinical
outcome [1]
• Both the duration of the periodof aortic clamping and
the duration of cardiopulmonary bypasshave been
consistently shown to be the main determinants of
postoperative outcomes of cardiac surgery [2-4].
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3. • Antegrade cardioplegia remains the single most
widespread mode of administration to protect
the myocardium during cardiac surgical
procedures [5].
• However, in patients with severe coronary artery
disease, cardioplegia maldistribution can occur
withthe use of antegrade cardioplegia alone [6-8]
• These potential problems may be overcome by
direct delivery of cardioplegia via grafts.
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4. • In this study, our aim was to investigate the
beneficial effects of intermittent antegrade
aortic root and graft cardioplegic delivery
combined with early perfusion of the grafted
ischemic myocardial segments with warm
arterial blood during the construction of
proximal graft anastomosis on myocardial
protection and performance in on-pump
CABG procedures.
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5. MATERIALS AND METHODS
• A prospective, randomized clinical trial was
planned.
• Following the permission of the Institutional
Review Board of our hospital, between June
2006 and October 2009, 96 patients
undergoing on-pump CABG were randomly
divided into two groups consisting of 48
patients each.
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6. • Group A (n=48) received antegrade cardioplegic
infusion via the aortic root;
• Group B (n=48) received antegrade cardioplegic
infusion via the aortic root supplemented with
antegrade perfusion of vein or free arterial grafts
after each distal anastomosis was completed.
Additionally, graft perfusion with warm arterial
blood was applied after the cross-clamp until the
proximal anastomosis was completed.
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7. The use of a multiple
perfusion set (MPS) in
group B patients
•In this technique, the aortic perfusion
branch of the MPS is kept clamped
during the cross-clamp period, and
each vein or free artery graft is
perfused in an antegrade fashion
following completion of distal
anastomosis in addition to
cardioplegia being administered from
the aortic root.
After the cross-clamp is taken off, the
clamp on the aortic branch is removed
and early perfusion with warm arterial
blood is initiated.
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8. • The groups were compared by clinical and
biochemical markers of ischemic myocardial
damage.
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9. RESULTS
Patients in each group were similar
with respect to most of the
preoperative characteristics
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10. At the end of cardiopulmonary bypass,
most of the data were similar between
the two groups. No statistically significant
differences were noted between the
mean number of distal anastomoses or
mean aortic cross-clamp and partial
occluding clamp times.
However, the mean CPB time in group B
was significantly lower than that of group
A (82.9±13.4 min in group A vs. 75.1±16.5
min in group B, p=0.01).
After declamping the ascending aorta,
sinus rhythm returned spontaneously
without electrical defibrillation in 21
patients (43.8%) from group A as
compared with 41 (85.4%) from group B
(p<0.001). Conversely, 27 patients
(56.2%) from group A and 7 patients
(14.6%) from group B needed
defibrillation after aortic declamping. The
need for defibrillation was significantly
higher in group A (p<0.001).
The number of patients who did not
require any inotropic support was
statistically higher in group B (p= 0.03).
There was no significant difference
between the two groups in regards to the
number of patients requiring low or
medium dose inotropic support.
However, more patients who underwent
antegrade aortic root cardioplegic
delivery alone required a high dose of
inotropic support (p= 0.02).
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11. After surgery, there were significant increases in the
peak serum CK-MB and cTn-I levels in both groups,
indicating myocardial injury (p=0.002 in group A and
p=0.008 in group B). When compared to group A, group
B showed lower peak levels of cTn-I and CK-MB at 12
hours (p=0.01 and p=0.02, respectively).
After surgery, there were significant increases in the
peak serum CK-MB and cTn-I levels in both groups,
indicating myocardial injury (p=0.002 in group A and
p=0.008 in group B). When compared to group A, group
B showed lower peak levels of cTn-I and CK-MB at 12
hours (p=0.01 and p=0.02, respectively).
After surgery, there were significant increases in the peak serum CK-MB and cTn-I levels in both groups,
indicating myocardial injury (p=0.002 in group A and p=0.008 in group B). When compared to group A, group
B showed lower peak levels of cTn-I and CK-MB at 12 hours (p=0.01 and p=0.02, respectively).
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12. • The peak serum cTn-I and CK-MB level differences were more significant in
the subgroup analysis at 12 hours. In the subgroup of severe right coronary
artery stenosis (>90%), CK-MB: p=0.007 and cTn-I: p=0.008 (Figures A and B),
and in the subgroup of low left ventricular ejection fraction (30-40%), CK-MB:
p=0.002 and cTnI: p=0.004 (Figures C and D).
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13. • In regards to the echocardiographic data taken on the sixth
postoperative day, both types of myocardial protection techniques
demonstrated minimal improvement in the left ventricle ejection
fractions. Mean preoperative LVEF% values were: group A,
47.7±8.5; group B, 48.4±9.4 (p=0.64). Mean postoperative LVEF%
values were: group A, 48.9±7.9; group B, 51.7±7.6 (p=0.08).
• The mean length of intensive care unit stay was: group A, 2.72±0.53
days vs. group B, 2.54±0.35 days (p=0.04); mean hospital stay was:
group A, 7.58±1.4 days vs. group B 7.08±0.8 days (p=0.04).
• There were three hospital mortalities between 3-15 days
postoperation: one (2.08%) in group A due to mesenteric infarction
and two (4.16%) in group B due to generalized sepsis and multi-
organ dysfunction.
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14. Discussion
• In the present study, we have applied a technique similar to
the method Goldman et al. first described in 1987 [20].
• Our version of the technique facilitates antegrade selective
cardioplegia perfusion by means of free grafts following
each distal anastomosis in addition to antegrade
cardioplegia administered from the aortic root in the
beginning.
• This technique can also supply blood flow to the ischemic
myocardium during construction of the proximal graft
anastomosis, promoting early reperfusion and rapid
recovery of grafted ischemic myocardial regions, which may
decrease ischemia time.
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15. • Our findings are in accord with the suggestion that
selective antegrade graft cardioplegia may lead to lower
rates of myocardial injury by homogenous distribution of
cardioplegia solution, especially in areas of critical coronary
artery stenosis or complete coronary artery occlusion.
• In addition to this, our technique facilitates earlier warm
blood perfusion of the grafts, and thus the ischemic
myocardial areas, until the proximal anastomosis is
performed and the cross-clamp is taken off.
• Together, these factors may lead to a lower rate of
ischemia-reperfusion injury, earlier recovery from
myocardial deterioration, and a minimized risk of post-
ischemic myocardial dysfunction.
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16. CONCLUSION
• We believe that our technique may prove useful
in lowering the mortality and morbidity rates
following surgery in patients with multi-vessel
coronary artery stenosis and poor ventricular
function when compared with other myocardial
preservation methods.
• Combined with our technique, retrograde
cardioplegia may improve this preservation even
more. However, we believe that further studies
with a larger group of patients are needed to
reach a definitive conclusion.
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