European Journal of Cardio-Thoracic Surgery, Vol 12, 20-24, Copyright © 1997 by European Association for Cardio-thoracic Surgery
Minimally invasive thoracoscopically assisted coronary artery bypass surgery
M Mack, T Acuff, P Yong, GK Jett and D Carter
Columbia Hospital at Medical City Dallas, TX, USA.
OBJECTIVE: Minimally invasive techniques have been widely used in other
surgical fields including video-assisted thoracic surgery (VATS) in
thoracic surgery. These concepts are now being applied to cardiac surgery.
The opportunities to make cardiac surgery less invasive include elimination
of the median sternotomy incision, elimination of cardiopulmonary bypass
and no manipulation of the aorta. MATERIALS AND METHODS: From January 1992
through September 1996, various aspects of minimally invasive cardiac
surgery have been examined in the inanimate endoscopic trainer, animal
model, human cadaver and in human clinical studies. Techniques of
endoscopic sutured anastomosis as well as alternatives to suturing were
first perfected in the inanimate trainer. Twenty animals then underwent
endoscopic coronary artery bypass using the left internal mammary artery to
the left anterior descending with circulatory support from an axial flow
pump. Fifty eight minimally invasive coronary artery bypass procedures have
been performed in humans using thoracoscopic assistance for internal
mammary artery harvest. RESULTS: One hundred fifty endoscopic coronary
anastomoses were performed in the inanimate trainer with the endoscopic
suturing technique being the preferred method. Time required to perform an
anastomosis decreased from greater than 60 min to a mean of 20 min as
technique and instruments were developed. In animals, methods of access as
well as enabling surgical instruments to allow crossclamp of the aorta and
performance of the anastomosis were developed. Fifty-eight humans underwent
coronary artery bypass using the left internal mammary artery placed to the
left anterior descending under direct vision through a limited anterior
thoracotomy on a beating heart. The procedure was successful in 52 patients
with conversions required in six patients. Techniques were developed for
immobilization for performance of the anastomosis. DISCUSSION: The ability
to perform an endoscopic anastomosis still remains the rate limiting step
for totally endoscopic coronary artery bypass surgery. The present MIDCAB
(minimally invasive direct coronary artery bypass grafting) procedure is a
significant advance in cardiac surgery, but still has limitations that make
performance of an exact anastomosis still somewhat difficult and applicable
only to single-vessel disease. Present efforts are directed toward
extending the MIDCAB procedure by various immobilization and circulatory
support devices and combining the MIDCAB procedure with catheter techniques
for treating more advanced disease.
