Heart surgery has come a long way over the past 120 years, but new advances are making procedures safer and easier than in generations past. Learn about some of the classic, always-reliable methods and some groundbreaking new procedures.
Since the first recorded open-heart procedure in the mid-1890s, surgeons have been improving their skills and processes for mending broken hearts. From tried and true procedures to the introduction of brand new ones coming to the Rockford region this year, the steady advancement of modern medicine is providing patients with new hope.
While open-heart bypass surgery remains the best way to treat badly blocked arteries, it’s far less invasive than it once was. And in some cases, surgery may be avoided altogether, thanks to alternative procedures such as stenting, ablation and the new kid on the block: transcatheter aortic-valve implantation (TAVI).
Angioplasty and Stents
Over time, a waxy substance called plaque builds up in some peoples’ arteries, causing a condition known as atherosclerosis. When this happens in coronary arteries, it may eventually cause angina, which is pain or discomfort in the chest. Plaque buildup narrows and even hardens arteries, restricting blood flow and promoting blood clotting. Worse, clots can attach to the plaque and then break loose, blocking blood flow and leading to the most common cause of heart attacks.
Cardiac patients rushed into the emergency room at KSB Hospital in Dixon are swiftly assessed and then taken to the cardiac catheterization lab. Dr. Peter Schalk, director of cardiology at KSB, says lives are saved here nearly every day. Just as emergency responders refer to the “golden hour,” in which patients with heart attacks and strokes can avoid massive or permanent damage to muscle and tissue, cardiac surgeons have their own crucial schedule.
They often perform angioplasty, a procedure which became the gold standard for emergency heart care in the 1990s. Angioplasty may or may not be combined with stent implementation. Angioplasty is a technique for mechanically widening an obstructed blood vessel, by guiding a collapsed balloon to the blockage and inflating it to move fatty deposits, thereby widening the passage for blood flow. The balloon is then deflated and removed.
“Door-to-balloon time should be 90 minutes or less,” Schalk emphasizes. “A team, consisting of a cardiologist, technologists and nurses, stands ready to speed the process and prevent as much damage as possible. KSB’s cardiac catheterization lab has been open for six years, and we have the door-to-balloon window narrowed to about 60 minutes.”
According to nationwide studies, when cardiologists rely solely on the balloon to open and restore blood flow, the procedure results in a 30- to 50-percent restenosis, or re-narrowing of the artery.
“We used this procedure and hoped the artery would stay open,” Schalk says. “But the added use of stents and drug-eluting stents has dramatically reduced restenosis rates in the coronary arteries.”
In a stent procedure, a tiny incision is made either in the patient’s femoral artery at the groin or brachial artery in the arm. A small catheter is threaded up the aorta and guided into the coronary arteries. Once there, an angiogram, or a picture of the heart, helps doctors to verify the blockage. The balloon and stent are advanced to the blockage and inflated, pushing the plaque buildup to create a lumen, or opening in the artery. Then the compressed mesh stent is expanded and secured into place. Everything except the stent is removed.
“Basically, stenting buys time for most patients,” Schalk explains. “It postpones the need for open-heart surgeries. Patients in their 40s or early 50s, who would have had to undergo bypass surgery, were likely to need another heart bypass surgery in their lifetimes, if not multiple surgeries. Stenting can essentially delay or eliminate the need for heart bypass surgery.”
While stenting has become fairly routine, Schalk says some patients are not good candidates for it. Unfortunately, everyone is built differently; genetics, lifestyle, and chronic diseases such as diabetes and high blood pressure may complicate coronary artery disease.
“Occasionally, we begin catheterization only to find the patient has multiple blockages that are too severe, or the blockages have become too calcified,” Schalk says. “At this point, angioplasty and stenting would not be the appropriate choice for the patient, who would be a better candidate for bypass surgery. When we find this situation, we arrange for the patient to be flown to one of the region’s major heart treatment centers for bypass surgery.
Just as a plumber removes and replaces eroded, blocked pipes from under a sink, cardiothoracic surgeons remove and replace blocked artery segments. Of course, pipes don’t jump around while plumbers are working on them, and no lives are at stake.
The first successful bypass surgery was performed on May 2, 1960, in New York City. Since then, the fundamental concept hasn’t changed much, says Dr. John Myers, chief of surgery at The Heart Hospital at SwedishAmerican Hospital in Rockford. However, the ancillary surgeries and technologies related to the procedure have improved tremendously. During his 22 years as a cardiothoracic surgeon, Myers has witnessed many of these improvements.
“One major advance is that we always scope to harvest the vein we need for the replacement segments,” Myers says. “Patients no longer have full-leg incisions, because we can remove the vein through a 2- to 3-centimeter incision.”
This process is called endoscopic vessel harvesting. The most common source for viable veins is the great saphenous vein in the leg, although sometimes the radial artery in the arm is used.
In more than 90 percent of bypass surgeries, the surgeon separates the internal left thoracic artery from the chest wall and sews its end directly to the artery in the front of the heart.
“The left internal thoracic artery to the left anterior descending artery is the best bypass regarding long-term success, staying open for 10 years, 90 percent of the time,” says Myers.
Emerging stem cell research offers the potential for growing replacement arteries, but implementation is problematic, says Myers. While some bypass surgeries are elective, many are in response to immediate need, and patients usually don’t have time to wait.
“If patients don’t have good veins for harvesting, we can use deep-frozen veins from cadavers, but they don’t stay open very long,” he says. “The patient’s own veins are, by far, the best option, offering a 95-percent success rate initially, but a 60- to 70-percent, 10-year patency rate.”
Progress has also improved the healing process. Like harvesting incisions, bypass incisions are smaller than ever. And Myers no longer uses staples to close the chest incision. Instead, he sutures below the skin and glues the skin over the incision, which offers a better cosmetic outcome and fewer post-operative problems.
Myers emphasizes that there’s no such thing as an average patient or a routine procedure. Each patient is assessed as an individual, not only for heart condition, but also for circumstances related to weight, use of tobacco, alcohol or drugs and more. A medical history of diabetes, high blood pressure, strokes and kidney disease must be evaluated. Even after a history is taken and all tests are conducted, the extent of the surgery still depends upon what the surgeon finds when the patient’s chest is opened.
“Sometimes we anticipate a triple bypass procedure but might actually do one bypass combined with two stents,” Myers says. “It’s tailored to exactly what the patient needs. Nothing about bypass is set in stone. We must always look at the overall picture, as well as the exact condition of the patient’s heart and vessels.”
Myers anticipates several more surgical advancements. “Tests indicate that bypass patients do better with the use of stem cell therapy, using cells harvested from their own bone marrow,” he says. “This improves circulation.”
The da Vinci robotic tool already in use for minimally invasive reproductive system surgeries has been adapted to heart surgeries in some facilities.
“But the surgeries can be longer and the costs higher,” Myers says. “And that remains one of the biggest challenges we surgeons face. The high cost of new technology has slowed its spread. But I believe the next generation of cardiothoracic surgeons, these younger physicians who have grown up with computers and gaming interfaces, are going to be more amenable to robotic versus hands-on instrumentation, when it comes to open-heart surgeries.”
Treating Atrial Fibrillation
Plumbers and cardiothoracic surgeons have another challenge in common: bad valves. Just as blocked or eroded valves trouble the plumbing, diseased valves trouble the heart. Heart valves can develop stenosis, a condition in which they don’t open widely enough, slowing blood flow and possibly causing blood to back up into a patient’s lungs or other places. Valves may not close tightly enough, causing what cardiologists call “insufficiency.” Blood can leak through the valve and go the wrong way.
Faulty heart valves can also cause atrial fibrillation (A-fib). A patient with A-fib experiences abnormal heart rhythm – a disorganized, irregular, quivering beat of 300 to 600 beats per minute, instead of the normal sinus rhythm of 60 to 80 beats. More than 2 million Americans have A-fib, which may cause blood to pool in the heart’s upper chambers, substantially increasing the possibility of clot development and stroke.
“The most common reasons patients develop A-fib are valve disease, high blood pressure and aging,” says Dr. Arif Ahmad, a cardiologist at Monroe Clinic, Monroe, Wis.
He adds: “The potential grows with each decade.”
Factors that can directly and indirectly influence the onset of valve disease and A-fib include kidney, liver and coronary artery disease, sleep apnea, diabetes, hypertension, infection and strokes, Ahmad explains. Lifestyle factors such as obesity, stress and excessive use of alcohol or caffeine play a role, too. Sometimes, doctors can’t identify a specific cause.
“A-fib brings up other health issues, including stroke prevention,” Ahmad says. “Blood thinners and close monitoring are often our first approach.” Valve disease evolves over time and most commonly occurs in the aortic and mitral valves. Aging and calcification within the valves can lead to blood flow restriction. A lesser-known cause is bicuspid aortic valve disease, in which the aortic valve narrows or begins to leak.
“The gold standard for valve disease is surgical repair or replacement of the valve,” Ahmad says. “Valve replacements may be metallic or biological, meaning they may be taken from pigs, cows or human donors. We can repair mitral valves if enough healthy tissue remains. But if we need to remove too much, or if the tissue is damaged beyond repair, we do the replacement procedure.”
Ablation is another innovative method of controlling A-fib. During ablation, tiny cuts are made in precise points within the heart, creating scar tissue that interrupts the electrical impulses that trigger heart beat arrhythmias. Ablation can be performed as an open-heart surgery or a minimally invasive procedure similar to stenting. A new modified, minimally invasive version, called catheter radiofrequency ablation, allows surgeons to deliver heated or extremely cold impulses to target areas.
“This has been effective in 50 to 80 percent of patients on the first try,” Ahmad says. “However, it works best on younger patients and involves much greater risk. But in the right hands and for the right patient, ablation is a viable solution for atrial fibrillation.”
Ahmad describes the future of valve surgeries as a “Pandora’s Box,” but says techniques and medications are improving constantly. Stem cell research applied to cardiomyopathy and other heart disease conditions may add more ammunition to the treatment arsenal. However, Ahmad doesn’t expect the regrowing of heart valves and other tissues to become a reality anytime soon.
“Advances in antiarrhythmic drugs and ablation methods are steadily reducing risks,” Ahmad says. “Open-heart surgery is comparatively safer now than ever before. And now, with TAVI, only time will tell if the rigors of surgery are worth the risks involved.”
In late spring, OSF Saint Anthony Medical Center in Rockford will bring TAVI, the latest advancement in heart valve replacement, to the region. An alternative to open-heart surgery, TAVI is a minimally invasive procedure that replaces degenerated aortic heart valves with bovine pericardial bioprostheses – cow heart valves.
The process is similar to heart artery stenting, except that the compressed stent holds a cow valve within its mesh. The tiny package is delivered through the artery and positioned within the old valve. When the stent snaps open, it crushes the old valve and allows the replacement to expand into place. No “cracking of the chest” or sutures are needed.
“The principle was that, if we can do stents, we should be able to apply the same principle to valve replacement,” says Dr. Jan Skowronski, an interventional cardiologist with OSF Saint Anthony Medical Center. “TAVI was introduced in France about 10 years ago. The first human procedure was performed in 2002. Doctors have been doing TAVI in Europe for the past six years. We even tried to send our patients to Germany for the procedure, but the cost was prohibitive, around $60,000. I am personally familiar with cases of American celebrities who went to Europe to have this procedure done. Because the Federal Drug Administration is ultra-conservative, TAVI was not approved in the United States until late in 2011.”
Skowronski and Dr. David Cable, a cardiothoracic surgeon with Rockford Surgical Service, traveled to Germany last year to attend a TAVI hands-on training program. The doctors view TAVI not only as a way to prolong life, but also to improve quality of life, since bad valves are a natural part of aging, mostly afflicting people 70 and older. While traditional treatments require open-heart surgery to replace human heart valves with animal or mechanical ones, TAVI bypasses that invasive procedure, significantly reducing risk.
“Working in tandem, Dr. Cable and I don’t exactly stop the heart during TAVI,” Skowronski explains. “We use a temporary pacemaker to speed the heart rate to more than 200 beats per minute, and during this time, we implant the new valve. It only takes about 15 to 20 seconds, nothing like the time a patient spends on a heart-and-lung machine during heart surgeries. In the skilled hands of German physicians, TAVI takes just 45 minutes.”
Skowronski says TAVI patients spend about three days in the hospital, take required medications for about three months post-surgery and take aspirin for life.
“It wasn’t unusual for patients to linger in the hospital after traditional heart valve surgeries and face months of recovery,” Skowronski says. “While TAVI is not totally without risks, it may be safer and can be offered to patients who otherwise would not be candidates for open-heart surgery.”
Skowronski anticipates the area’s first TAVI procedures will take place in late May or June of this year.
Heart disease continues to be the No. 1 killer of both men and women. By enhancing traditional bypass surgery and building on its solid foundation, cardiologists are saving the lives of millions of people. ❚