Journal of Long-Term Effects of Medical Implants
A. P. KYPSON ET AL.
454
II. EVOLUTION OF ROBOTIC
CARDIAC SURGERY
Given the availability of telemanipulative systems,
endoscopic robotic cardiac operations have become
possible and have evolved through graded levels of
diffi
culty with increasingly less exposure to a progres-
sive reliance on video assistance. In this scheme, entry
levels of technical complexity are mastered premoni-
tory to advancing past small incision, direct-vision
approaches (Level I), toward more complex video-
assisted procedures (Levels II-III), and fi nally, to
robotic cardiac operations (Level IV).
II.A. Level I: Direct Vision and Mini-Incisions
Initially, minimally invasive cardiac valve surgery
was based on modifi cations of previously used
incisions and performed under direct vision. In
1996, mini-sternotomies, parasternal incisions, and
mini-thoracotomies were used in the fi rst minimally
invasive aortic valve operations. In Cosgrove's fi rst
50 aortic procedures, operative times approximated
conventional operations, and mortality was 2%, with
half of the patients being discharged by postoperative
day fi ve. Cohn presented his series of 41 minimally
invasive aortic operations and demonstrated economic
benefi ts. Others also found that minimal access in-
cisions provided adequate exposure of the mitral valve.
Surgical mortality (13%) and morbidity were com-
parable to those of conventional mitral surgery. Falk
reported on 24 mitral valve repairs performed through
a mini-incision with Port-accessTM techniques.¹ By
1997, the New York University group had done 27
Port-accessTM mitral repairs/replacements with one
death. Th
ere were no aortic dissections and no repairs
had residual regurgitation requiring reoperation.¹¹
Port-accessTM methods were also used for coro-
nary artery bypass operations.¹²¹³ Th
rough incisions
other than a median sternotomy, cardiac standstill was
feasible, allowing surgeons to graft multiple vessels.
Port-accessTM coronary operations proved effi
cacious
although they were more complex and required longer
perfusion times. Results of a prospective multicenter
trial¹ on 302 consecutive patients demonstrated an
operative mortality of 0.99%, with a 3.3% incidence
of reoperation for bleeding and a 1.7% incidence
of stroke. Th
ese encouraging results confi rmed the
feasibility and safety of these techniques and further
advanced the next level of "minimal invasiveness."
II.B. Level II: Video-Assisted and Micro-Incisions
Video assistance was fi rst used for closed chest in-
ternal mammary artery harvests and congenital heart
operations.¹¹ Although Kaneko¹ fi rst described the
use of video assistance for mitral valve surgery done
through a sternotomy, it was Carpentier¹ who in Feb-
ruary 1996 performed the fi rst video-assisted mitral
valve repair via a minithoracotomy using ventricular
fi brillation. Th
ree months later, our group performed a
mitral valve replacement using a microincision, video-
scopic vision, percutaneous transthoracic aortic clamp,
and retrograde cardioplegia.²²¹ In 1998, Mohr re-
ported 51 minimally invasive mitral operations using
FIGURE 3B. ZeusTM instrument arms. Note that they are
mounted directly to the surgical table.
