Effect of lead position and orientation on electromagnetic interference in patients with bipolar cardiovascular implantable electronic devices

Electromagnetic interferences (EMIs) with cardiovascular implantable electronic devices (CIEDs) are associated with potential risk for patients. Studies imply that CIED sensitivity setting and lead's tip-to-ring spacing determine the susceptibility of CIEDs with bipolar leads to electric and magnetic fields (EMFs); however, little is known about additional decisive parameters affecting EMI of CIEDs. We therefore investigated the influence of different patient-, device-, and lead-depending variables on EMIs in 160 patients. We ran numerical simulations with human models to determine lead-depending variables on the risk of EMI by calculating the voltage induced in bipolar leads from 50/60 Hz EMF. We then used the simulation results and analysed 26 different patient-, device-, and lead-depending variables with respect to the EMI threshold of 160 CIED patients. Our analyses revealed that a horizontal orientation and a medial position of the bipolar lead's distal end (lead-tip) are most beneficial for CIED patients to reduce the risk of EMI. In addition, the effect of CIED sensitivity setting and lead's tip-to-ring spacing was confirmed. Our data suggest that in addition to the established influencing factors, a medial position of the lead-tip for the right ventricular lead as achievable at the interventricular septum and a horizontal orientation of the lead-tip can reduce the risk of EMI. In the right atrium, a horizontal orientation of the lead-tip should generally be striven independent of the chosen position. Still important to consider remains a good intrinsic sensing amplitude during implant procedure.