Journal of Long-Term Effects of Medical Implants
A. P. KYPSON ET AL.
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method and eventually were able to complete bilat-
eral internal mammary artery grafts off -pump to the
anterior descending and right coronary arteries while
working from one side of the chest.³³³
In September of 1998, Reichenspruner³ performed
an endoscopic robotically assisted coronary anasto-
mosis using the ZeusTM system. He used a standard
myocardial stabilizer inserted through a mini-thora-
cotomy. Th
e pericardiotomy, vascular occlusion, and
dissection of the LAD were all manually performed
using conventional instruments. Damiano³ fi rst ex-
panded coronary surgery with ZeusTM to the United
States; and Boyd, at the London Health Services
Center in Canada, reported on six successful closed-
chest beating-heart single-vessel revascularizations
using the same system.³ Despite early procedural
success, future refi nements in these devices are needed
to apply this new technology more widely.
III. CLINICAL APPLICATIONS/PATIENT
SELECTION
Early in the development of any minimally invasive
cardiac surgery program, strict inclusion and exclusion
criteria should be followed. In our initial experience
with robotic mitral repairs, all patients had isolated
mitral insuffi
ciency. Patients with a previous right
thoracotomy were excluded from the da VinciTM pro-
cedures; however, we now approach these patients with
a video-assisted mitral valve operation. Patients with
severely calcifi ed mitral annulus are not candidates. De-
calcifi cation requires further instrument development
as well as a reliable means to evacuate any calcium that
may fall into the left ventricle. Patients with mitral valve
stenosis were excluded in the early FDA trials; however,
patients treatable by commissurotomy would be suitable
candidates for robotic repair. Th
e improved visualiza-
tion of the valve and subvalvular apparatus along with
the maneuverability of bladed microinstruments would
facilitate performance of a commissurotomy.
As previously discussed, early eff orts at totally
endoscopic coronary surgery using conventional
instruments were discouraging and were hampered
with imprecision and two-dimensional visualization.
With the development of computer-assisted telema-
nipulation systems and three-dimensional visualiza-
tion, TECAB has not only become feasible but has
also been demonstrated to be safe. Nevertheless, with
current technology, these operations are usually per-
formed on single vessel (LAD) disease with either
an arrested heart using the Port-AccessTM system, or
a beating heart using specially designed endoscopic
stabilizers. Clinical trials are currently underway in
Europe and North America.
IV. OPERATIVE TECHNIQUES
IV.A. Mitral Valve Surgery
Pre- and postoperative surface and transesophageal
echocardiographic (TEE) studies are performed. Pa-
tients are anesthetized and positioned with the right
chest elevated 30°40° and the right arm suspended,
padded, and positioned over the forehead. Single left-
lung ventilation is used for complete intrathoracic
exposure.
Cardiopulmonary bypass is established at 26 °C
using femoral arterial infl ow and kinetic venous drain-
age through a femoral (2123 Fr) and right internal
jugular vein (17 Fr) cannula. If the femoral artery is
too small or atherosclerotic, either a Bio-MedicusTM
(Medtronic, Minneapolis, Minnesota, USA) or Di-
rectfl owTM (Cardiovations, Somerville, New Jersey,
USA) cannula can be placed through a second inter-
space port for antegrade aortic perfusion. A 45 cm
infra-mammary incision is used, and a subpectoral
fourth-intercostal space (ICS) mini-thoracotomy is
developed to provide cardiac access. Th
e pericardium
is opened under direct vision 2 cm anterior to the
phrenic nerve. Antegrade cardioplegia is given by an
aortic needle/vent placed either under direct vision
or videoscopically. To minimize intracardiac air en-
trainment, the thoracic cavity is fl ooded continuously
with carbon dioxide at 12 liters per minute. A trans-
thoracic aortic cross-clamp (Scanlan International,
Minneapolis, Minnesota, USA) is positioned in the
