The stent significantly improved chest pain, quality of life, and coronary microvascular function in patients in a phase 2 clinical trial.
Summary: A Mayo Clinic study published in JACC: Cardiovascular Interventions suggests that an innovative hourglass-shaped stent may help alleviate severe and recurrent chest pain in patients with coronary microvascular disease. In a phase 2 clinical trial with 30 participants, 76% reported improvements in daily activities after 120 days, with some regaining the ability to walk up stairs or around the block without pain. Unlike traditional tube-shaped stents, this new design narrows in the center to increase back pressure, redistributing blood flow in the heart’s tiny vessels. While the results are promising, further research is needed to identify which patients benefit most from this therapy.
Key Takeaways:
- Novel Stent Design Offers Relief: The hourglass-shaped stent improved blood flow and reduced chest pain in over three-quarters of study participants with microvascular disease.
- Enhanced Quality of Life: Participants who struggled with routine activities due to chronic angina were able to resume normal physical tasks, showing significant improvement after treatment.
- Future Research Needed: The therapy did not alleviate symptoms in up to 30% of patients, highlighting the need for more studies to identify optimal candidates for this treatment.
A study at Mayo Clinic suggests that an hourglass-shaped stent could improve blood flow and ease severe and reoccurring chest pain in people with microvascular disease.
Of 30 participants in a phase 2 clinical trial, 76% saw improvement in their day-to-day life. For example, some participants who reported not being able to walk around the block or up a flight of stairs without chest pain were able to do these ordinary physical activities at the end of a 120-day period.
Clinical measures of blood flow related to the microvasculature of the heart significantly improved during follow-up, according to findings published in the Journal of the American College of Cardiology: Cardiovascular Interventions.
Microvascular Disease and Need for New Treatment Options
Microvascular disease is a condition in which tiny blood vessels in the heart are not working properly, resulting in reduced blood flow to the heart. The resulting chest pains, or angina, can be debilitating, limiting a person’s ability to exercise, do household chores, or even walk to the mailbox.
About 40% of patients receiving a diagnostic coronary angiogram for chest pain do not have blocked arteries that also can cause angina. However, up to 66% of these patients do have coronary microvascular disease, which is more common in women overall and found in people with conditions such as diabetes, high blood pressure, and obesity.
For decades, there have been few viable treatment options to improve blood flow through the tiny vessels of the heart. At most, doctors have treated symptoms of angina with several medications and cardiovascular disease prevention methods, including healthy eating, weight loss, and regular exercise. The use of a stent could target the issue behind the chest pain—the severe reduction in blood flow affecting the heart muscle.
Testing an Hourglass-Shaped Stent
Unlike tube-shaped stents used to open clogged arteries, the hourglass-shaped stent narrows in the middle. The different design is thought to increase back pressure, redistributing blood flow more fully through small vessels in the heart that were not working at capacity.
“The patients with heart-related microvascular dysfunction in this study had little ability to control their chronic angina, which severely limited their day-to-day activities,” says Amir Lerman, MD, a cardiologist at Mayo Clinic and senior author of the study, in a release. “Beyond reductions in chest pain and being able to comfortably handle more physical activity, the majority of patients in the study also showed a connection between the changes in their coronary flow reserve, which is a measure of maximum blood flow, and changes in their quality-of-life responses on the survey. This points to the link between the physiological measurement and angina symptoms.”
Lerman notes that more studies are needed to better understand how the reducer stent works and its long-term effects on blood flow. The stent did not improve chest pain symptoms in 20%-30% of the participants, so future research studies will need to better identify which patients respond best to this therapy.
Photo caption: View of a heart with coronary artery disease or coronary microvascular disease. An inset highlights the clogging and narrowing of the arteries.
Photo credit: Mayo Clinic
