A small study has suggested that radiation therapy may be a safer alternative to invasive catheter ablation for treating recurrent episodes of a dangerous heart rhythm disorder known as ventricular tachycardia, and is nearly as effective.
Patients suffering from ventricular tachycardia often rely on high-dose medications that can cause significant side effects, in addition to implantable defibrillators that deliver powerful and painful electric shocks when needed. When drug therapies fail, patients typically undergo catheter ablation, a surgical procedure that involves inserting a tube into the heart to destroy the tissue responsible for the abnormal rhythm. However, repeated ablation procedures carry substantial risks and can lead to serious complications.
In the recent study, researchers compared 22 patients treated with stereotactic radiation therapy to 21 patients who had undergone multiple catheter ablations. The findings revealed that four patients in the ablation group died within one month, all due to treatment-related complications. By contrast, no deaths occurred among those who received radiation therapy during a three-year follow-up period, according to results presented at the American Society for Radiation Oncology (ASTRO) annual meeting.
After one year, hospital admissions due to treatment-related side effects were reported in 38% of patients in the catheter ablation group, compared with only 9% among those who received radiation therapy. Both treatments were found to be similarly effective in preventing recurrence, with the average time to a new arrhythmia episode or defibrillator shock recorded at 8.2 months for the radiation group and 9.7 months for the ablation group.
Complications appeared much sooner following catheter ablation—typically within six days—while in the radiation group, they arose after an average of ten months. After one year, 73% of patients treated with radiation were still alive, compared to 58% of those who underwent ablation. By the three-year mark, survival rates for both groups evened out at 45%.
Researchers believe the longer initial survival among radiation-treated patients is likely due to avoiding anaesthesia and the early complications associated with invasive surgery.
However, they cautioned that the study’s small sample size limits the strength of its conclusions. Ongoing clinical trials directly comparing the two treatment methods are expected to provide more definitive evidence on the potential of radiation therapy as a safer, non-invasive alternative for managing life-threatening cardiac arrhythmias.
