When patients are in the throes of a heart attack, there's no question that stents save lives.
But for heart patients with few symptoms and less than severe artery blockage, whether to use a stent is a question with no clear-cut answer, say cardiologists. In fact, these days some heart experts say the mesh metal tubes used to keep narrowed or weakened arteries propped open are overused for blockages that can be treated just as well with medicine, a healthy diet and exercise.
A recent internal review of heart patients at St. Joseph Medical Center in Towson found 369 patients received the coronary implants unnecessarily. Those findings have sparked one lawsuit so far and threats of more to come - while highlighting a debate among cardiologists and confusion among patientsover when stents are necessary.
So, what's a patient to do? For those in the middle of a heart attack with unrelenting symptoms, stents are the best option, cardiologists say. But for others, the answers can vary.
"It's not black and white," said Dr. Mark Hlatky, a professor of cardiovascular medicine at Stanford University. "This is a whole shade of gray."
The key for patients is education. Understand your test results, know the options available and ask plenty of questions of your doctor well before you undergo any procedures, cardiologists advise.
Stents are typically placed in an artery after an angioplasty, a procedure in which clogged vessels are cleared with a balloon to restore blood flow to the heart. Stents act as scaffolding, keeping the arteries pushed open so they can stay clear for years after the procedure.
In the 1990s, coronary artery stents were welcomed by doctors and patients alike, offering a less invasive, cheaper alternative to bypass surgery, and an option more effective than angioplasty on its own. Since then, about 1 million stents have been implanted each year in the United States.
But they don't come without risks. Patients must be on blood-thinning medication for a year or longer. There's a risk of complications during stent placement and beyond, including blood clots and heart attack. Once they're put in, stents can't come out.
In recent years, clinical trials have shown medication to be as effective in some circumstances, and an internal debate has been brewing over whether doctors rely too heavily on the implants.
Stents only relieve symptoms; they don't make you live longer, Hlatky said, adding that he falls on the conservative side of the debate. The first question any physician and patient should ask is if interventions are needed at all or whether a person's symptoms could be helped with drugs alone, he said.
If an intervention is needed, the second question should be what kind: a stent or bypass surgery, he said. Bypass surgery is usually reserved for patients with more extensive heart disease and multiple severe blockages, while stents work best for patients with one or two blockages, he said.
"The strategy should be, let's try drugs first," Hlatky said. "If they work, we'll keep using them. If they are not working and you keep having symptoms, we'll go ahead and use an angioplasty [and stent]. But this should not be routine for anyone."
Dr. Monica Aggarwal, a noninvasive cardiologist at Mercy Medical Center, agrees stents should only be used when medicine and lifestyle changes have failed. When a patient comes to her with chest pain, Aggarwal must figure out if it's cardiac pain or something else such as heartburn, muscle pain or a lung problem.
"A patient should be asking: What are my symptoms, are they cardiac or not? What are my risk factors?" she said.
If symptoms indicate pain is coming from the heart, a doctor typically orders a stress test, which evaluates how well the heart is working after exercise. Some stress tests can tell where on the heart that blood flow is stalled.
If the test is abnormal or shows blood flow is restricted in important areas, then a doctor and patient should discuss the options.
"[Patients] should ask, do we need a stress test? What is the stress test looking for?" said Dr. Claudia Hochberg, an interventional cardiologist at Boston Medical Center. "And then, afterward, what kind of abnormality is found? What's the best way to treat it?"
A normal test may simply require more monitoring. Even with an abnormal result, a patient might do well with medicine and a change in lifestyle, such as quitting smoking, eating better and exercising, she said.
When a stress test reveals that more than one vessel is restricted or blood flow is blocked in a major artery branch on the left side of the heart, most cardiologists will take a closer look to determine how bad the clog is, using cardiac catheterization. In that procedure, a tool is inserted in the leg and threaded up to the heart, Hochberg said.
If the arteries are very clogged, most doctors put in a stent.