Drug-Eluting Versus Bare-Metal Stents for Symptomatic Intracranial Vertebral Artery (V4) Stenosis: A Single-Center Cohort Study

The human brain relies on a constant, delicate flow of blood to function, a supply delivered through a network of arteries that wind through the neck and into the skull. Among these, the vertebral arteries are critical pathways, and the segment known as V4 sits deep inside the cranium, navigating a complex, curved route to feed the back of the brain. When fatty deposits, or plaque, build up on the inner walls of these vessels, they can narrow the passage, a condition called stenosis. This narrowing restricts blood flow and significantly increases the risk of a stroke, a sudden interruption of that vital supply. For patients who suffer symptoms like dizziness or weakness despite taking medication, doctors sometimes turn to a mechanical solution: inserting a tiny mesh tube, or stent, to hold the artery open.

For decades, the medical community has debated which type of stent works best for these delicate intracranial locations. The traditional option is a bare-metal stent, a simple metal scaffold that physically pushes the vessel walls apart. A newer alternative is the drug-eluting stent, which is coated with a medication that slowly releases into the artery wall to stop cells from growing too quickly and clogging the tube again. While drug-coated stents have revolutionized heart treatments, their performance in the brain's unique environment remains less certain. The brain's blood vessels are thinner and more fragile than those in the heart, and the flow dynamics are different, leading researchers to question whether the benefits seen in cardiology translate directly to neurology, particularly for the tricky V4 segment of the vertebral artery.

A team of researchers at Beijing Geriatric Hospital set out to answer this specific question by looking back at the records of patients treated between January 2021 and June 2025. They focused on 105 individuals who had severe narrowing in their intracranial vertebral arteries and had recently experienced symptoms like a transient ischemic attack or a minor stroke. These patients were divided into two groups based on the device their doctors chose: 56 received drug-eluting stents, and 49 received bare-metal stents. The researchers tracked these patients closely for six months, monitoring for two main things: whether the artery narrowed again inside the stent, and whether the patients suffered another stroke or died during the recovery period.

The study found that both types of stents were safe to implant, with no major difference in the risk of complications during the first 30 days after the procedure. Whether a patient received a drug-coated tube or a bare metal one, the immediate risk of a stroke or death was comparable, suggesting that the newer technology did not introduce extra danger during the surgery itself. However, the long-term picture told a more nuanced story. When the researchers examined the arteries six months later, they found that the drug-eluting stents were associated with a lower rate of the artery narrowing again. While this difference in the physical narrowing of the vessel did not reach the threshold of statistical certainty, the trend was clear: fewer patients in the drug-eluting group experienced restenosis compared to those with bare-metal stents.

More importantly, the data revealed a significant clinical benefit for the drug-eluting group. Over the six-month follow-up, patients who received the drug-coated stents had a much lower rate of ischemic strokes—those caused by blocked blood flow—compared to the bare-metal group. Specifically, about 5.7 percent of the drug-eluting patients suffered a stroke during the follow-up, whereas nearly 19 percent of the bare-metal patients did. This suggests that the medication on the stent may be doing more than just keeping the vessel wide; it might be preventing the formation of tiny clots or stabilizing the vessel wall in a way that protects the brain from future events. The researchers noted that in the bare-metal group, half of the restenosis cases were linked to new symptoms, whereas none of the restenosis cases in the drug-eluting group caused symptoms, further highlighting the protective nature of the drug-coated devices.

The authors acknowledge that their study has limitations, primarily because it was a single-center review where doctors chose the stent type rather than a random assignment, which could introduce subtle biases. The sample size was also relatively small, meaning that while the trends are strong, the results are suggestive rather than definitive proof. Nevertheless, the findings offer a compelling glimpse into the potential of drug-eluting stents for this specific, high-risk group of patients. The study concludes that for those with symptomatic narrowing in the deep vertebral arteries, drug-eluting stents appear to be a safe option that may offer superior protection against future strokes and vessel re-narrowing compared to traditional bare-metal alternatives, warranting further investigation in larger, more diverse studies.