New technique allows surgeons to perform complicated heart operations (9/03/98)
Tate Williams is only 5 years old and looked even younger lying in his bed at University Hospital. A slender, blue-eyed child with baby-fine, blond hair, Tate didn't want to be bothered when Mickey Ryerson, nursing director of the pediatrics intensive care unit, tried to examine him. So he fussed a little and told Nurse Ryerson to go away. When that didn't work, a tear appeared in the corner of his eye and trickled down his cheek. To the casual observer, he looked like any child with a minor illness.
But Tate isn't like other children--he was born with an abnormal aortic valve. When he was just 24-hours-old, he underwent an emergency balloon procedure to open a dangerously narrow valve in his heart. Now he was in the hospital again recovering from a complicated surgical procedure to replace his faulty aortic valve.
A few minutes after the nurse left, Tate was propped on a pillow in a Red Flyer wagon, playing a Nintendo game with his mother, Christa. Within another 24 hours, he would be back home with his family.
If this sounds miraculous--to undergo complicated heart surgery one morning and less than 24 hours later be playing Nintendo games, and within an additional 24 hours be back home again--it is as close to a miracle as most of us are likely to see.
But John Calhoon, MD, professor and division head of cardiothoracic surgery, and colleagues Scott Johnson, MD, assistant professor, and John Kupferschmid, MD, assistant professor and chief, section of congenital heart surgery from the department of cardiothoracic surgery at The University of Texas Health Science Center at San Antonio, perform miracles almost daily. The Calhoon team routinely corrects heart defects, frequently using the Heartport system and the Ross Procedure. Heartport manufactures the Port Access system for keyhole coronary artery bypass surgery and for valve repair and replacement, such as Drs. Calhoon and Kupferschmid performed on Tate.
Commonly known as minimally invasive surgery, the procedure requires the surgeon to make one or more 1 1/2- to 3-inch incisions, and with specially designed clamps and tools to operate on the heart through these small openings. During the procedure, the patient is connected to a heart-lung machine through a specially designed catheter.
"Because the incisions are strategically placed, the patient doesn't have to go through life with this big stripe down his chest," Dr. Calhoon said.
Used with keyhole surgery, the Ross Procedure makes surgery technically more difficult but allows most patients to leave the hospital within three or four days after surgery and to return to normal activities within three or four weeks. In this complicated procedure, the surgeon uses the patient's own pulmonary valve, identical in size, shape and strength, to replace the faulty aortic valve.
"Tate was referred to us by Dr. Kenneth Bloom, a prominent San Antonio pediatric cardiologist," Dr. Calhoon said. "During Tate's operation we took out his pulmonary valve and moved it to the aortic position, after having removed the aortic valve, and we used an oversized, donated cadaver valve in the pulmonary position. He may eventually grow into his oversized valve and, if he outgrows it--which might not happen because it is quite large--it can easily be replaced."
Dr. Calhoon makes this extremely complicated surgical procedure sound easy. It isnít. Dr. Calhoon made history in 1993 when he and his team replaced 2-day-old Gilbert Hernandez III's defective heart valve in a six-hour operation. Gilbert, perhaps the youngest child ever to undergo such a complicated procedure, survived and has done well. Since that time Dr. Calhoonís surgical team has performed many operations using keyhole surgery.
"We didn't call it keyhole surgery when we first started using this procedure," Dr. Calhoon said, smiling. "I donít think the term had been invented yet.
"This procedure isn't something that is used for most re-operative valve surgeries, however," Dr. Calhoon cautions, "and it can't yet be used to redo most patients. But there are actually some procedures where it is best, and the reason it is best is because if there is an isolated vessel that has a lesion and the patient has had several bypasses and one has failed, the faulty vessel can be accessed through a small incision and the surgeon doesn't have to work through all the old scar tissue."
Dr. Johnson said, "Minimally invasive surgery isn't unique. What we are doing that is unique in San Antonio is using the Heartport technology." Dr. Johnson explained that in bypass surgery new pathways for blood flow are provided for the patient past any blockages and coronary arteries. Minimally invasive surgery is normally used only for one or two bypasses, and the heart is still beating.
"With Heartport we are able to do complicated procedures that once could have been done only with open-heart surgery," Dr. Johnson continued. "The balloon clamp is inserted through the aorta and blown up, isolating the heart from the rest of the circulatory system. This can all be done without ever opening the chest. The surgeon then has complete access to the arteries through a tiny incision. The heart is placed on a bypass machine that performs the work of the patient's lungs and heart, and a cardioplegia solution is delivered to the heart to make it still and bloodless.
"Another nice aspect is that we can harvest the entire vein through a two-inch incision," Dr. Johnson concluded. "Some patients are as wary of the venous aspect as the heart surgery itself. The minimally invasive technique eliminates that concern."
Dr. Kupferschmid, the newest team member, explains that each surgeon looks at the keyhole procedure from a slightly different angle. "One of the things we see, more in adults than in kids, is that when the breastbone is involved in open heart surgery the entire sternum is unstable for a while," Dr. Kupferschmid said. "Keyhole surgery prevents this. Also, as Dr. Calhoon pointed out, there are innumerable cosmetic advantages.
"In Tate's surgery, the incision was made right where we were going to operate," he added. "We had a nice, easy approach. We didn't need to see the entire heart."
Asked about future plans for his team, Dr. Calhoon replied, "We are searching for an investigator to do minimally invasive research in the laboratory. Our group wants to do lab research directed at refining techniques and, in the next two or three months we hope to do port-type incisions. Also, we will tackle more complicated procedures."
Dr. Calhoon says he learns every time he performs surgery. "Port access, marketed by Heartport, allows us to perform multivessel coronary artery bypasses, and mitral and aortic valve repairs and replacements, with keyhole surgery."
The typical hospital stay for patients who have surgery using the port access procedure is two to four days as opposed to a week or longer when conventional bypass surgery is used. Total recovery time is two to four weeks.
For now, though, children and adults who need to have a valve replaced or a hole in their heart closed may choose to have minimally invasive surgery performed by the Health Science Center team. This should hasten the heartbeats of all cardiovascular patients in the South Texas area.
Contact: Jan Elkins (210) 567-2570