Valve jobW. Randolph Chitwood MD

Professor and Chairman, Department of SurgeryEast Carolina University School of MedicineGreenville, NC

Wylie Nifong MDAssistant Professor, Cardiothoracic SurgeryEast Carolina University School of MedicineGreenville, NC

Despite rapid advances in minimally invasive techniques in other surgical specialties, cardiac surgeons have lagged behind in developing minimal access methods.

Cardiac surgery has traditionally been done through larger breast-bone incisions to allow full access to the heart.

Advances in less invasive cardiac surgery are now being made both in Europe and the United States.

The earliest minimally invasive procedures were done through smaller incisions, using the surgeon's eyes and hands.

Procedures then developed using videoscopic screens, but still using long instruments.

Minimally invasive proceduresCardiac surgery

Robotic surgery

Robotic or computer-enhanced operations are the next step.

Hand motions the surgeon makes while sitting at a console are transmitted through computer to instruments within the patient’s chest cavity.

Instead of long instruments, microwrists, extensions of the human wrist, are used to perform procedures.

The da Vinci EndoWrist™

The next step

©1998 Intuitive Surgical

The German experience

From June 1996 to December 1998, 129 patients with non-ischemic mitral valve disease underwent 3D-video-assisted mitral valve surgery via a 4-cm right lateral minithoracotomy using femoro-femoral bypass and endoaortic clamping.

Group 1: port-access minimally invasive surgery the first 62 patients who underwent the procedure

Group 2: port-access robot-assisted solo surgery catheter design was modified and the procedure

was redefined and simplified after the initial 62 patients

the procedure was completed as robot-assisted solo surgery, without an additional assistant

2 years of mitral valve surgery

Mohr FW, et al. Eur J Cardiothorac Surg 1999;15(3):233-238

The German experience

Mohr FW, et al. Eur J Cardiothorac Surg 1999;15(3):233-238

ResultsGroup 1 (n=62)

Group 2 (n=67) p value

Time for surgery (min) 188 52 152 56 <0.005

Clamp time (min) 69 26 48 16 <0.002

Intubation time (h) 19 7 14 6 <0.002

ICU time (days) 2.3 1.6 1.3 0.9 <0.002

Hospitalization (days) 13 3 10 3 <0.002

Mean survival (95% CI)

Group 1 (n=62) 88.7%* at 804 35 days (735–873)

Group 2 (n=37) 97.0% at 568 12 days (553–600)

*partially procedure related (aortic dissection in 2 patients)

FDA-approved trial

The first Specific Investigational Device Exemption (IDE) clinical trials are being performed with the da Vinci device at the Ohio State University Medical Center in Columbus, Ohio, and at East Carolina University/Pitt Memorial Hospital in Greenville, North Carolina.

The FDA approved a protocol for 10 microvalve operations.

Microvalve surgery using the articulated wrist

A tiny camera with multiple lenses, inserted into the patient's chest, provides a 3-dimensional image of the heart.

The surgeon, at a nearby computer workstation, can see inside the chest through a viewport and uses a pair of joysticks to control the robotic arms.

Robotic surgery

©1999. Courtesy The Ohio State University Medical Center, used by permission.

The American experience

Minimally invasive heart surgery using the da Vinci computer-enhanced surgical system being performed at The Ohio State University Medical Center.

©1999. Courtesy The Ohio State University Medical Center, used by permission

Robotic surgery

The camera is inserted through a 5-cm incision.

2 additional incisions (ports) are made, 1 for each robotic arm.

A 5-mm incision is made in which to place a clamp that goes across the chest wall to interrupt the heart.

Smaller incisions

©2000 Computer Motion. Photography B. Benett

Robotic surgery

Damiano RJ. J Thorac Cardiovasc Surg 1999;117:1212-1215

Schematic illustration of a robotic operative setup. Surgeon seated at console operating on the master manipulator controlling motions of the robotic arms via computer interface.

OR setup

©1999 J Thorac Cardiovasc Surg

Robotic surgery

The ultimate goals are to make cardiac surgery less debilitating and to shorten the recovery period.

With videoscopic procedures, the hospitalization period dropped from 7 days to 3.5 days.

With robotic devices, the hospitalization period will probably drop to 2.5–3 days.

Faster recovery

The AESOP scope

The FDA-approved AESOP (Automated Endoscope System for Optimal Positioning) is a single voice-controlled robotic arm that understands 23 simple commands such as "move up," "right," "left," "back," "return," and "move in."

©2000 Computer Motion

©2000 Computer Motion

The AESOP scope

Patients who had surgery with the AESOP did much better

significantly shorter stay in ICU

significantly reduced time on ventilator

significantly fewer blood transfusions

shorter hospital stay (mean of 3.8–3.9 days vs 8 days for conventional sternotomy incision)

Because patients had fewer complications and were discharged from hospital sooner, AESOP procedures actually cost 28%–33% less than standard mitral valve surgery.

Faster recovery and cost effective

Micro-mitral operation

The Micro-mitral operation begins with cardiopulmonary bypass established through femoral arterial and venous cannulas inserted under direct vision using the Seldinger technique.

The heart is accessed through a 6-cm right lateral minithoracotomy (or "instrumentation port") made in the 4th intercostal space at the anterior axillary line.

Chitwood WR. J Thorac Cardiovasc Surg 1997;114(5):773-782

©1999 J Thorac Cardiovasc Surg

Micro-mitral operation

Either a 5-mm 2-dimensional endoscopic rod-lens camera with screen monitor or a 3-dimensional digital camera with a head-mounted display is used for intracardiac visualization and to guide instrument manipulation.

Aortic cross clamping is performed through the intact chest wall using a special transthoracic clamp with sliding rod design.

Chitwood WR. J Thorac Cardiovasc Surg 1997;114(5):773-782

Standard anterograde cardioplegic arrest is used for myocardial preservation.

Valve excision, suture placement, valve or annuloplasty ring seating, and knot tying are performed with videoscopic visualization and instrumentation.

Transthoracic clamp©1999 J Thorac Cardiovasc Surg

The AESOP scope

In the US, all cardiac surgeons have general surgery training with experience in endoscopic and laproscopic surgery (operating from a monitor).

Most surgeons involved with robotics have experience with less invasive approaches using cameras and videoscopic technology.

Although robotic technology provides 3- dimensional images, it is a leap in the procedure to operate on the heart looking at a monitor.

Learning curve