Using stents to treat chest pain
A recent study published in The Lancet medical journal resulted in news headlines that stents may not be effective for treating patients with chest pain. But as with any medical study, it’s important to examine the size of the study, the way that it was conducted, and the statistical significance of the data before changing any guidelines about patient treatment.
Stents are small wire devices used to open arteries that are used to treat patients suffering a heart attack or dealing with recurring chest pain (angina). For patients in emergency situations, stents will continue to be a life-saving treatment. But even for patients with routine angina, stents continue to play a role in effective treatment for certain patients.
The study published in The Lancet involved a selective group of patients, as it took three to four years for researchers to gather 200 patients at five major medical centers. Some patients were immediately excluded because their symptoms were severe enough to need a stent, rather than be entered into a study with a placebo where not all patients would receive the stents. All patients in the study had only one artery blocked that was resulting in chest pain.
Another area of concern for the study is the follow-up period of six weeks. Following a stent procedure, most physicians will recommend one or two weeks of inactivity to allow full recovery. Thus, the monitoring period involving normal activity was even less than six weeks. Ten patients in the placebo group also failed to complete all follow-up activities, which is a significant number of lost patients for a study size of 200.
About 60% of the patients in the study had class two angina, which is chest pain that typically occurs with moderate to heavy activities. But these patients were not running up stairs or pushing wheelbarrows in the weeks immediately following surgery, so their episodes of chest pain likely would have changed simply from inactivity.
Patients in the study were also treated with medications before receiving stent surgery or a placebo procedure. For patients with mild to moderate angina, treatment with medications can reduce the occurrence of episodes, so some patients in the study may have reduced their angina simply through medication.
The study results also showed a higher than normal complication rate for both stent and placebo patients, which raises further concerns about the experience of the physicians in the study with placing stents. Also, in an optimized stenting procedure, the pressure in the artery upstream from the blockage and downstream from the blockage should match when the procedure is complete, but the artery pressure did not match in this particular study suggesting the blockages were not adequately treated in some of the patients.
No medical study is perfect, which is why there are always multiple studies to look at the same medical questions over time. While this one study led to many headlines and discussion among the medical community, our basic recommendations for patients have not changed: if you are experiencing angina, see your doctor, have the appropriate tests done, and discuss your range of treatment options.
Some patients with recurring angina may respond well to treatment with medications alone, while others may need a stent procedure to reduce symptoms and allow for normal daily activities. Each patient situation is unique, and our Oklahoma Heart Hospital physicians are ready to help.