Appendix Update on Coronary Artery Bypass Surgery: Current and Future Trendspatients like those in the trials is unknown, but the
relatively small number of patients in RCTs is wor-
risome. In comparison, approximately 1,200,000
myocardial infarctions occur in the United States
annually [2]. More problematic still is that only
three of the RCTs were performed in the United
States. These initiatives require much greater
funding to conduct the necessary RCTs, as well as a
greater commitment from U.S. patients and physi-
cians to increase enrollment in future RCTs.
In this era of higher risk patients referred for
cardiac surgery, avoidance of the use of a pump and
the subsequent adverse systemic reaction has been
regarded as a strategy to manage the risk of periop-
erative mortality and morbidity in coronary revas-
cularization. With the increased age of the population
and the increasing number of referrals for operation
in patients with severe valvular disease (e.g. aor-
tic stenosis) and diffuse calcifi ed coronary artery
stenosis, a changing strategy is necessary to manage
the risk of perioperative mortality and morbidity in
coronary revascularization and valvular heart
disease. Many surgical referrals will be requested for
patients with high risk morbidity and mortality.
However, the applicability of minimally invasive
or off-pump coronary artery bypass grafting is
limited by its technical profi le and by the possibility
of inadequate revascularization in some patients
with severe stenosis and complex anatomy of the
coronary lesions. An investigation by Mazzei and
associates [19] provides evidence that the degree of
the systemic infl ammatory reaction and the release
of markers of end-organ damage are comparably
modest whether coronary revascularization is per-
formed off-pump or on-pump with the use of the
minimal extracorporeal circulation system. This
biochemical fi nding is demonstrated by the compa-
rability of mortality, morbidity, and intensive care
unit/hospital length of stay after the use of either
strategy despite a similar preoperative risk profi le of
the study groups.
Three questions must be answered. Should the
minimal extracorporeal circulation system and off-
pump coronary artery bypass grafting be considered
equivalent tools to obtain a lower rate of periopera-
tive morbidity? If so, should we more commonly use
the minimal extracorporeal circulation system to
perform on-pump coronary surgery in elderly and
high-risk candidates? Will this approach facilitate
complete revascularization and perhaps better graft
patency rates than with off-pump coronary artery
bypass grafting? Important answers to these queries
cannot be obtained without rigorous multicenter
investigations.
Despite initial promising results it is doubtful that
improvements in CPB will ever achieve the results
obtained by complete avoidance of CPB. Off-pump
bypass can only deliver optimal results to patients if
complete and precise revascularization is achieved.
The learning curve for this new operation is longer
than for the conventional arrested-heart procedure
and requires a modifi ed set of skills and techniques.
There is considerable enthusiasm for the hypothesis
that complete revascularization with multiple arte-
rial grafts can occur without CPB and without aortic
manipulation. Only time will tell.References available online at http://www.Wiley.com/go/
AHAGuidelineHandbook.During the production of this book this relevant
AHA statement and guideline was published: Car-
diovascular Monitoring of Children and Adoles-
cents With Heart Disease Receiving Medications for
Attention Defi cit/Hyperactivity Disorder, http://
circ.ahajournals.org/cgi/content/full/117/18/2407.