Electromagnetic Interference Between Left Ventricular Assist Device and a Three-Dimensional Mapping System Overcome by "Hot Mapping"

Urgent catheter ablation in Japanese patients with mechanical circulatory supports suffering from refractory ventricular electrical storm

BACKGROUND

Therapeutic strategy using catheter ablation for ventricular tachyarrhythmias (VTAs) electrical storms in patients dependent on percutaneous mechanical circulatory support (MCS) has not yet been established.

METHODS

We reviewed the patients with or without requiring MCS who received urgent VTAs ablation in our institute between January 2020 and May 2022. Electrophysiological and clinical outcomes were compared between those with and without requiring MCS.

RESULTS

Twenty procedures (16 patients, median 76 years, 13 males) were included. Six procedures using MCS underwent ablations and the other 14 procedures were performed without MCS. Although VTAs cycle lengths were not significantly different between the two groups, the incidence of hemodynamic stability was significantly higher in MCS group than in those without (83 % vs. 29 %, p = 0.024). Temporary MCS were explanted in all patients following the successful ablation, whereas the complication rates were higher in patients requiring MCS (67 % vs. 0 %, p = 0.001). Cumulative incidences of cardiovascular death and appropriate therapy of implantable cardioverter defibrillator within 90 days following the procedures were not significantly different between the two groups (p = 0.071 and p = 0.063, respectively).

CONCLUSION

Urgent ablation might be a feasible bail out option for those dependent on MCS suffering from VTAs, although physicians should be on high alert for device-related bleeding.

[Electromagnetic interference in 3D-mapping procedures]

Catheter-based ablation is nowadays a safe and widespread procedure for the treatment of cardiac arrhythmia. This requires exact anatomical knowledge both before and during the examination and is an important prerequisite for targeted treatment. At the beginning of the era of interventional catheter-based treatment, fluoroscopy was the only and usual means of visualization, whereas in the middle of the 1990s continuous 3D-mapping systems were developed for the non-fluoroscopic examination of patients. The correct use of these 3‑D systems, which non-fluoroscopically visualize the catheter and mostly identify mechanisms of arrhythmia in great detail, nowadays makes an important contribution to successful interventional catheter treatment of arrhythmia; however, it is not uncommon for patients with ventricular arrhythmia to also carry implanted electronic devices, such as pacemakers, defibrillators or less frequently left ventricular hemodynamic support systems. All implantable devices lead to electromagnetic interferences, which can complicate the diagnostics and treatment during electrophysiological examinations and ablation. This article addresses the adversities and experiences associated with magnet-based 3D systems and implantable electromagnetically active cardiac devices.