The phrase robotically assisted cardiac surgery can be misleading. The name makes the surgery sound easy, as if the robot performs a good deal of the work while the doctor simply supervises. That's not the case at all, but robots are helping surgeons at Columbia Presbyterian Medical Center perform heart surgery in a way that is less invasive than traditional open heart surgery.
Dr. Michael Argenziano, assistant professor of surgery at P&S, and his Columbia Health Sciences colleagues use a surgical robot the Da Vinci Surgical System to help with some of the most common cardiac surgeries, including arrhythmia ablation, coronary artery bypass, valve repair, and fixing holes in the heart. NewYork-Presbyterian Hospital has two Da Vinci robotic systems one at the Columbia Presbyterian campus and one at the Weill Cornell campus.
Robotically assisted surgery only requires small incisions between the ribs to enter the chest cavity instead of having to open the chest by cutting through the sternum, as in traditional open-heart surgery. Once the incisions are made, tiny instruments and cameras are placed inside the chest cavity by an assistant surgeon. The surgeon sitting at a console a few feet from the patient controls the robot much as a driver controls a car. As the surgeon works, his or her cutting and suturing movements are transmitted in real-time to the instruments through a computer interface. The robot preserves the surgeon's dexterity and actually eliminates any unsteadiness in the surgeon's hand, allowing arteries as small as 1.5 millimeters to be stitched together.
Most recently, Dr. Argenziano and his colleagues have been testing minimally invasive surgery as a way to cure atrial fibrillation, a type of heart rhythm abnormality. More than 2 million people in the United States have the condition, which disrupts the normal electrical activity in their heart. Drugs are available to control the problem, but they are infrequently curative and have side effects. There also is an effective surgical technique, the Cox-Maze procedure, which is not widely used because it is extremely invasive. The technique requires multiple incisions in the heart's walls. "The Cox-Maze surgery is effective, but it is like shooting a mouse with a nuclear warhead," says Dr. Argenziano, director of robotic cardiac surgery and arrhythmia surgery at CPMC.
Seeing a need for a new method, Dr. Argenziano and fellow physicians in the Department of Surgery in 1997 began developing a minimally invasive procedure. Starting with animal studies, they practiced making incisions in the heart with novel energy sources, such as radiofrequency, microwave, and laser. In the past five years they have done nearly 200 atrial fibrillation operations, achieving a success rate of 76 percent.
This past February, the surgeons went one step further, performing their first completely closed-chest robotic atrial fibrillation surgery without putting the patient on a heart/lung machine. Surgeons have an ongoing debate about whether heart/lung machines cause cognitive damage in surgical patients.
Minimally invasive surgery has both advantages and disadvantages. The advantages are that the smaller incisions allow better wound healing and often cause less pain than traditional open-heart surgery. The disadvantages are that the operations typically take longer, are more complex, and require ancillary technology. In addition, costs are higher because of the price of the devices and the increased time in the operating room.
"Initially, cardiac surgeons were reluctant to use minimally invasive techniques for fear that limited exposure might result in a decreased safety margin. But with advances in technology and clinical experience, we can now perform a variety of minimally invasive cardiac operations without sacrificing patient safety," Dr. Argenziano says.
Dr. Argenziano and his colleagues, including Dr. Mehmet Oz, professor of surgery at P&S, and Dr. Craig Smith, the Calvin F. Barber Professor of Surgery, have participated in a number of trials testing the Da Vinci system during other types of heart operations. They were part of a multicenter mitral valve repair trial, operating on 17 patients at CPMC. On the basis of this trial, the FDA approved the procedure in November 2002. Dr. Argenziano also serves as the lead investigator of a multicenter totally endoscopic coronary artery bypass trial.
Dr. Argenziano also was an investigator in a national trial of atrial septal defect repair with the robot, which was the first totally closed chest surgery trial. That trial was completed late last year and also resulted in FDA approval.
"We have one of the largest robotic experiences in the country," Dr. Argenziano says. "We're figuring out what we can and can't do. The technology holds great promise to treat cardiovascular disease, the top killer of Americans."