Work

Preclinical and benchtop evaluation of a dedicated tool for insertable cardiac monitor explantation

Year: 2026

Type: article

Abstract: Background Insertable cardiac monitors (ICMs) are widely used for long-term rhythm surveillance, yet explantation can be challenging due to fibrotic encapsulation, tissue variability, and device migration. Current removal typically relies on general surgical instruments, and no dedicated tool exists for difficult ICM explants. Objective To evaluate the performance of a purpose-built cardiac monitor extraction tool (CM-eX) compared with standard removal technique using benchtop and chronic animal models. Methods The CM-eX was designed and fabricated. Benchtop testing used a two-layer synthetic gel model simulating fibrotic encapsulation and subcutaneous tissue. Eighty ICM removals were performed using CM-eX, standard instruments, or direct wire pullout. Metrics included removal time and peak insertion/removal forces. Electromyography was recorded as a measure of operator demand. Chronic animal testing was performed in nine rats implanted bilaterally with ICMs and explanted after a 3-month survival period, with each animal serving as its own control. Results In benchtop models, removal time was similar between CM-eX and standard instruments (p=0.40), while CM-eX required significantly lower removal force than direct pullout (p<0.0001). Overall EMG activity was similar between methods. In the chronic animal model, CM-eX was associated with faster explant in 8 of 9 paired comparisons, with a mean reduction of 28% versus standard instruments. No device slippage or procedural complications were observed. Conclusion In preclinical testing, CM-eX demonstrated feasible ICM removal with reduced extraction force in benchtop models and directional improvements in explant time in an animal model. These findings support its potential to facilitate more controlled and consistent ICM explantation.

Source: Heart Rhythm O2

DOI: 10.1016/j.hroo.2026.07.003