The robot scrubs in

Ingenious machinery is making heart bypass surgery less invasive, perhaps opening a new avenue in treatment of cardiac patients.

 

Stand around a fishing hole long enough and you're likely to hear a few lies. But this month Joseph M. Hendrickson went fishing for trout on the Octoraro Creek and told a story no one believed: Six weeks prior, surgeons used robotic arms to bypass three of his plaque-choked arteries, sewing the grafts onto his beating heart through an incision the size of your average fishing lure.

Two men who had undergone bypass surgery stepped forward to tell him they knew better. Each carried at least 6-inch scars from where doctors had sawed through their chests to get at their hearts.

"Does it still hurt when you tie your shoes? Can you remember everything?" they asked, referring to complaints that stopping the heart and putting patients on heart-lung machines can diminish cognitive ability.

"They just couldn't believe I was out fishing already," Hendrickson says. As the use of laparoscopic coronary artery bypass surgery has increased in popularity, more surgeons are using robotic arms, a tool that some say makes the operation easier.

In some cases, as with Hendrickson, doctors combine the surgery with angioplasty and stents.

"It's the best of both worlds," said Francis P. Sutter, the heart surgeon at Lankenau Hospital in Wynnewood who performed Hendrickson's surgery. "We can do this operation on very sick patients bypassing the most important artery, and leaving the rest for stents."

Sutter has used a robot to perform minimally invasive bypass in 104 of 254 bypass cases in the last 18 months. About a third of those patients also received stents. This year, he's on track to use the robot even more.

The number of traditional bypass operations has fallen over the last decade with the growing use of stents, small mesh tubes used to prop blood vessels open.

Coronary artery bypass reached a high in 1997, when 426,000 patients had the operation. By 2004, according to the latest data available, the number fell 28 percent, to 308,000 patients.

Over the same period, the use of stents grew 36 percent, from 580,000 to 790,000.

Now, coronary surgery may be primed for a comeback.

"We are seeing a blip upwards in the number of patients having minimally invasive surgery, but we expect to see an increase of 30 to 50 percent over the next five years," said John O. Goodman, a cardiac-care consultant who tracks trends in the industry.

Fueling the growth, thoracic surgeons say, are recent studies showing that medicated stents carry a small risk of blood clots that can lead to a heart attack.

"Stents looked to be perfect until recently," said Howard C. Herrmann, an interventional cardiologist at the Hospital of the University of Pennsylvania. "That discovery has put us on a level playing ground with surgery."

Other recent studies show that sicker patients receiving bypass surgery have a higher survival rate than those who get older bare-metal stents. Further, surgery may be a better option than stenting when patients have a blockage of the left anterior descending artery, known as the widow maker because it's associated with a high number of deaths among heart attack victims.

"There are lots of different ways to do the same thing," Herrmann said. "There will always be patients for whom surgery is better, and no trial can answer that for everybody."

 

Open-heart

Most bypasses, about 80 percent, are still done using open-heart surgery, where doctors split the sternum, spread the rib cage, and bypass blocked arteries using veins taken from the chest or legs. Patients typically spend a day or more in an intensive-care unit and months recovering.

That's what Nelson Hawthorne, 65, a smoker from Norristown, figured he'd be getting.

"I thought of it as a big gash in the side of my body," Hawthorne said. But instead of a large scar down the center of his chest, the only evidence of Hawthorne's bypass is a short red line under his nipple and two pencil-sized holes in his upper and lower chest.

"I feel great," he said, sitting in a chair in his hospital room last week.

A few days earlier Hawthorne lay on an operating table as a three-armed robot craned overhead.

The anesthesiologist deflated Hawthorne's left lung and pumped air inside his chest to compress his organs and create space for the automated hands.

Sutter located where he would make the small incision, feeling the left side of Hawthorne's chest while looking at an X-ray image of his heart.

He inserted a camera while two assistants positioned two robotic arms fitted with tiny surgical forceps and a heated cutting tool.

Then, seated a few feet from his patient, the surgeon peered through a three-dimensional scope and manipulated the robot's steel arms. Like a space-age marionette, the robot mimicked Sutter's motions inside Hawthorne's chest.

"This heart is huge," Sutter said as he worked above the swollen beating heart to harvest an artery along the chest wall that he would use as a graft.

An hour later Sutter cut away the thick layer of fat from the sack protecting Hawthorne's heart to excavate the clogged 2-millimeter artery.

The robot's work was done.

Through a small incision Sutter sewed the chest wall artery to the heart, and then listened to the artery's flow.

"It has good squirt," he said, his grin stretching his surgical mask.

 

Marvel or just marketing?

For patients such as Hawthorne and Hendrickson, the robot is a wonder of modern medicine, a testament to a doctor's power to fix the broken heart.

But some surgeons see the device as more marketing than marvel, insisting they can perform the same surgery with laparoscopic tools and scopes. They say attaching an artery to a beating heart does not yield as good a graft as sewing to a heart that is stopped - and that requires a heart-lung machine.

"The robot gets a lot of attention and publicity," says Charles R. Bridges, chief of cardiothoracic surgery at Pennsylvania Hospital. "From an evidence-based surgery point of view, the robot has yet to shine."

Joseph Y. Woo is a heart surgeon at the Hospital of the University of Pennsylvania who performed one of the first coronary bypasses using a robotic surgical device in 2002. He and Sutter say they are convinced that using the robot will prove better for patients.

"It looks like you're sitting inside the heart," Woo said. "It gives you very small incisions. The visualization is awesome." Unlike laparoscopic instruments, the robot has a full range of motion.

"I do not know what the future will hold, but the technology will continue to progress and become more precise and people will use it more," Woo said.

But as coronary-bypass techniques improve, so does stent technology. Researchers are working on ways to eliminate the polymer used in medicated stents that elevate the risk of clots that may lead to a heart attack.

"They are developing very clever stents that have small wells that hold the same drugs as current drug-eluting stents," Herrmann said. Once the drugs are spent, the stent behaves like its bare-metal predecessors.

Researchers are also working to perfect a bioabsorbable stent that would dissolve over a period of months.

The national average per patient for a bypass is $30,000, with or without a robot. A stent procedure, which is done through angioplasty, costs about $14,000 per patient, said Goodman, the analyst.

Goodman expects these two approaches to heart disease will converge, not grow further apart. Some surgeons are already training to install stents during bypass surgery, he said.

"When you combine minimally invasive surgical techniques with stents in hybrid procedures, you'll see a radical increase in patients," he said. "Heart centers that do not move in this direction will find themselves in trouble."

 


 

View a slide show of the operation at http://go.philly.com/health


Contact staff writer John Sullivan at 215-854-2473 or johnsullivan@phillynews.com.