Advances in Percutaneous Intervention Boost Success
In Japanese culture, there is a traditional belief that when the chest is opened, the spirit may be released, leaving behind a body that is no longer the person it was.
Could this influence explain the remarkable advances Japanese researchers are achieving in redefining what is possible in percutaneous interventions in heart disease? One area where new nonsurgical technologies are making a dramatic difference is in ending angina pain by clearing chronic total occlusions (CTO) of the coronary artery.
“Several years ago, we might try a percutaneous intervention in certain cases. The occlusions could be very hard, and difficult to penetrate with the equipment we had at the time. If we couldn’t get through in the first few attempts, there was a tendency to give up rather than risk pushing ahead. But now that we have better devices and better techniques, the success rate has risen to 80 percent or more,” Mark Sasse, MD said.
An interventional cardiologist, Sasse is an associate professor of medicine in UAB’s Division of Cardiovascular Diseases and spends much of his time in the cath lab clearing blocked coronary arteries.
“Two of the new devices I use are the CrossBossTM catheter with a spin tip that drills through blockages, and the StingrayTM coronary re-entry system with a balloon that expands the artery for insertion of a drug-eluting stent. The guide wires get to the area easier. They don’t get twisted, and it’s easier to control the placement of the wires as they advance,” Sasse said.
Sasse and his staff are one of the few teams in Alabama that perform the procedure.
“It’s usually done in an academic medical center because it takes longer than most cath procedures,” Sasse said. “It also requires more specialized training, equipment and staffing. Primary physicians may not be aware of the recent advances in what’s possible with this approach. When we receive referrals, we look at the film and histories. If patients are good candidates, we do the procedure, and then send them back to their referring physician who continues to follow them.”
“The ideal candidate is someone who has had a chronic total occlusion for three months or more, with only the coronary artery involved so that surgery isn’t required for other arteries. It is for patients with angina that is limiting their activities and their quality of life. Most patients we see are in their 50s, 60s, or 70s, but they can be any age if their heart function and health are strong enough to tolerate a longer procedure and the dye we use to see where the problems are.”
With angiogenesis creating new vessels to reroute blood flow as plaques gradually form in the coronary artery, bypass surgery for the coronary artery alone is rarely considered unless angina pain becomes unmanageable. The risk of morbidity and mortality is higher in surgical bypass and opening the chest requires a longer recovery.
“Another issue is that a vein graft has a limited life of ten years or so,” Sasse said. “In morbidly obese patients, there’s also the risk of poor healing that a percutaneous approach avoids.”
Coronary artery blockages usually begin as very fatty deposits that become fibrous and then very hard. The possibility of perforation from having to use increasingly stiff wires has been the main risk from the procedure.
“The new devices are more effective at getting through the hard areas and keeping the line on course,” Sasse said. “When necessary, we can also take a retrograde approach and work from the back of the blockage. Sometimes the back of the cap is softer. Perforation is rare. It usually seals, and if necessary, we can use a special stent to stop bleeding.”
Advances in the procedure have also reduced other risks. Less dye is used, so there is less risk of contrast-induced kidney damage.
In many cases, percutaneous intervention can also offer advantages over managing angina with medications.
“Younger patients in particular may have a difficult time accepting the limiting effects of having to modify their lives based on their disease. They are unable to participate in outdoor activities. They may not be able to continue in their work,” Sasse said. “Although the one-time cost of the procedure is larger, in the long run it may be more cost effective. Some medications are $500 a month. Over five years, that’s $30,000. There’s also the productivity of a person who can continue working to consider, and the savings of not having to go on disability.”
While other interventions to clear or bypass clogged arteries are primarily done to extend the length of life, Sasse says this procedure is about improving the quality of that life.
“This is about living better—relieving angina pain and improving function so patients can do the things they enjoy,” Sasse said.