• Posted October 1, 2025

Radiation Can Treat Heart Rate Disorder, Study Says

Targeted radiation therapy might be a safer way to treat a potentially dangerous heart rate problem, a new study says.

Radiation therapy treated ventricular tachycardia as well as a standard but complicated procedure called catheter ablation, researchers reported Sept. 29 in the International Journal of Radiation Oncology, Biology, Physics.

At the same time, fewer patients treated with radiation died or experienced serious side effects, compared to catheter ablation, results from the small-scale study show.

“For patients who do not respond to traditional therapies and are at high risk of complications, noninvasive radiation may be a safer alternative to repeating an invasive catheter ablation procedure,” said lead researcher Dr. Shannon Jiang, a radiation oncology resident at Washington University School of Medicine in St. Louis.

“Going under anesthesia for an invasive procedure can involve outsized risk for a person who’s already very sick,” she said in a news release. “With radiation, we don't have to use anesthesia. I think this study highlights that radiation being a noninvasive procedure helps us avoid a great deal of risk.”

Ventricular tachycardia is an abnormally fast heart rate emanating from the heart’s two lower chambers, known as the ventricles.

During an episode, the heart rate can surge to the point that it causes dizziness, shortness of breath, fainting, chest pain and, in extreme cases, cardiac arrest, according to the American Heart Association.

Patients with advanced ventricular tachycardia often must take high doses of heart drugs that cause difficult side effects, researchers said in background notes.

The standard alternative for patients who don’t respond to medications has been catheter ablation. During this procedure, a small tube is run into the heart through a vein in the leg to destroy heart tissue that’s causing the abnormal heart rhythm.

Recently, radiation therapy has emerged as a potential option for treatment. Focused beams of radiation kill off the heart tissue driving the abnormal rhythm, without the need for anesthesia, researchers explained.

For the new study, researchers analyzed records for 43 patients with high-risk, difficult-to-treat ventricular tachycardia. Most (90%) had previously undergone catheter ablation, and their end-stage VT was not responding to their medication.

Half of the patients received a single dose of radiation therapy, and the other half underwent another round of catheter ablation.

Both treatments were effective in controlling heart rhythm. The time until patients’ next persistent episode of ventricular arrythmia was a median of 8.2 months with radiation versus 9.7 months with catheter ablation, results showed.

However, four patients who received ablation died within a month of treatment and one did not survive the procedure, researchers said. All of the deaths were due to treatment-related side effects.

By comparison, no treatment-related deaths had occurred among the group treated with radiation after a three-year follow-up.

Also, within a year of treatment 38% of the ablation group required hospitalization due to side effects, compared with 9% of the radiation group. Complications occurred sooner after ablation, a median six days versus 10 months for radiation. (Median means half happened sooner; half, later.)

“From our study, it looks like radiation might be safer especially within that early time window,” Jiang said. “There wasn’t the same early peak in adverse events, and that seems to drive the benefit. Many of the early serious adverse events after ablation were closely followed, unfortunately, by patient deaths.”

Overall survival favored radiation — a median 28 months versus 12 months — but the difference was not statistically significant due to the small sample size, researchers noted.

“Our interpretation is that many patients lived longer after radiation because they avoided the early complications that can follow ablation,” Jiang said.

One year after treatment, overall survival was 73% for the radiation group and 58% for ablation, the study found. At three years, it was 45% in both groups.

While encouraging, the study is too small to prove the benefits of radiation therapy for ventricular tachycardia, Jiang said. Patients are now being recruited for a larger international clinical trial being launched to provide definitive proof of radiation therapy’s potential effectiveness.

“I think our research adds legitimacy to the approach and underscores its potential as an option for patients, especially those at high risk for complications from anesthesia or ablation,” she said.

Researchers also presented these results Tuesday at the American Society for Radiation Oncology’s annual meeting in San Francisco.

More information

The Cleveland Clinic has more on ventricular tachycardia.

SOURCES: American Society for Radiation Oncology, news release, Sept. 29, 2025; International Journal of Radiation Oncology, Biology, Physics, Sept. 29, 2025