Study Finds Radiation Therapy May Offer Safer Option Than Repeat Ablation for Ventricular Tachycardia

A new study suggests that stereotactic radiation therapy may be a safer alternative to repeat catheter ablation for patients with severe ventricular tachycardia (VT), a life-threatening heart rhythm disorder resistant to medication.

The retrospective analysis, presented at the American Society for Radiation Oncology (ASTRO) Annual Meeting and published in the International Journal of Radiation Oncology • Biology • Physics (Red Journal), is the first to directly compare cardiac radiation with catheter ablation.

“Several large, single-arm trials have confirmed that stereotactic radiation therapy is a safe and effective option for patients with recurrent ventricular tachycardia, but our study is the first to measure outcomes from cardiac radiation directly against those from standard catheter ablation,” said lead author Shannon Jiang, MD, a radiation oncology resident at Washington University School of Medicine. “For patients who do not respond to traditional therapies and are at high risk of complications, noninvasive radiation may be a safer alternative.”

Researchers reviewed records of 43 patients with end-stage VT treated between 2015 and 2018. Patients received either stereotactic radiation (n=22) or repeat catheter ablation (n=21).

Complications were significantly lower in the radiation group: within a year, 38% of ablation patients had serious side effects requiring hospitalization, compared with just 9% of radiation patients. Four patients died within a month of ablation, while no deaths in the radiation group were linked to treatment-related side effects over three years.

“From our study, it looks like radiation might be safer especially within that early time window,” said Dr. Jiang. “There wasn’t the same early peak in adverse events, and that seems to drive the benefit.”

Both treatments were equally effective at controlling arrhythmia. Median time to recurrence was 8.2 months for radiation and 9.7 months for ablation. Median overall survival favored radiation (28.2 vs. 12.2 months), though not statistically significant due to small sample size.

Dr. Jiang emphasized the study’s limitations, noting its small scale and retrospective design. A larger randomized trial, RADIATE-VT (NCT 05765175), is now underway.

She added, “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.”