Transcutaneous magnetic stimulation may safely reduce the burden of ventricular tachycardia (VT) during VT storm, according to results of a randomized clinical trial, published in JAMA Cardiology.
Patients (N=26) with 3 or more episodes of sustained VT in 24 hours were recruited for the Magnetic Stimulation to Treat VT Storm (STAR-VT; Clinicaltrials.gov identifier: NCT04043312) trial at the Hospital of the University of Pennsylvania between 2019 and 2021. Patients were randomly assigned 1:1 to receive a single session of transcutaneous magnetic stimulation or sham stimulation. Transcutaneous magnetic stimulation was delivered for 60 minutes at 80% of the monitor threshold at a frequency of 0.9 Hz. Patients were monitored for vital signs and via a 12-lead electrocardiogram. The primary outcome was freedom from sustained VT for 24 hours after randomization.
Patients in the intervention and sham cohorts were aged mean 66.9 (standard deviation [SD], 15.2) and 61.7 (SD, 10.6) years; 71% and 83% were men; 1.9 (SD, 0.5) and 2.2 (SD, 0.72) were taking antiarrhythmic drugs; 71% and 50% had coronary artery disease; 57% and 67% had hypertension; 29% and 50% had atrial fibrillation; and 71% and 50% had monomorphic VT, respectively. The number of VT episodes in the preceding 24 hours was 11.0 (SD, 8.7) and 14.8 (SD, 11.9), respectively.
VT recurred in the 24 hours after treatment among 29% of transcutaneous magnetic stimulation and 58% of sham recipients (P =.20).
During the 72-hour post-treatment period, VT occurred an average of 4.5 (SD, 7.2) times in the transcutaneous magnetic stimulation group and 10.7 (SD, 13.8) times in the sham group (incidence rate ratio [IRR], 0.42; P <.001). Stratified by the first and second 24 hours after treatment, VT occurred fewer times among transcutaneous magnetic stimulation recipients in the first 24 hours (IRR, 0.18; P <.001) but not the second 24 hours (IRR, 0.88; P =.60).
At 24 hours, transcutaneous magnetic stimulation recipients reduced their antiarrhythmic drug intake (mean, 1.8 vs 0.9 drugs; P =.001) and the sham group did not (mean, 1.9 vs 2.3 drugs; P =.20).
No safety concerns were reported.
This study was underpowered to detect significant differences in the primary outcome.
“In this randomized clinical trial of patients with VT storm, results demonstrated that [transcutaneous magnetic stimulation] has the potential to safely reduce the burden of VT,” the study authors wrote. “These findings should inform future investigations of the optimal strategies for [transcutaneous magnetic stimulation].”
Disclosure: Multiple authors declared affiliations with industry. Please refer to the original article for a full list of disclosures.
Markman TM, Pothineni NVK, Zghaib T, et al. Effect of transcutaneous magnetic stimulation in patients with ventricular tachycardia storm: A randomized clinical trial. JAMA Cardiol. Published online February 16, 2022. doi:10.1001/jamacardio.2021.6000