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in outcomes between DES and surgery or between on-pump and off-pump
procedures.
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6.7.2 Off-pump cardiac surgery
Coronary artery bypass surgery remains an established form of treatment
for coronary artery disease. The majority of coronary surgical procedures
are performed for multiple vessel disease.
Results following multiple vessel coronary surgery are excellent with
two-year re-intervention rates of only 6% and a cumulative risk of death
and myocardial infarction of 12% over two years post-surgery. Although
the mortality rate of coronary artery surgery is low, at approximately 2%,
it is age related and rises to over 6% in those over 75 years of age. This
benefi t is offset by a complication rate of 20% to 30%. In addition, there
is a two to three month period of recovery from the fatigue that usually
follows any major operation.
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Percutaneous interventions had a dramatic effect on coronary artery
bypass surgery, arresting the dramatic growth of surgery in the 1980s and
shifting the attention of surgeons to patients with more advanced coronary
disease and extensive coexisting conditions. This has motivated surgeons to
refi ne coronary revascularization techniques in order to maximize clinical
effectiveness, limit costs, and reduce invasiveness. In contrast to the small
incision approaches, off-pump coronary artery bypass surgery through a
median sternotomy has gained clinical acceptance and in many centers
constitutes 20-30% of the total volume of coronary surgery. Creation of the
distal anastomoses is facilitated by the use of stabilizers that reduce the
motion of the heart in an area of approximately 2 cm
2
. The argument in
favor of this approach is to avoid the historical, well-documented adverse
effects of CPB on end-organ function: coagulation, renal impairment, lung
injury, and, most important in the aging population, avoidance of stroke,
delirium, and more subtle neurocognitive changes. The counter-argument
is that potential suboptimal exposure and hemodynamic instability during
off-pump procedures could produce inferior short and long-term outcomes.
The distinction between on-pump and off-pump coronary artery surgery is
over-simplistic since both methods encompass a range of techniques.
Early randomized studies performed on low risk patients have shown a
shorter length of stay, a reduced use of transfusion products, a reduced
incidence of coagulopathy, and a lower frequency of atrial fi brillation in
patients who undergo off-pump coronary artery surgery. There was no dif-
ference in outcome in the fi rst one to three years after surgery between
off-pump and standard groups.
The intense interest in the modern development of beating heart
surgery for coronary artery disease has been fuelled by the expectation
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