·Pacemakers and Implantable Cardioverter Defibrillators (ICD) are highly sophisticated electronic medical implants designed to treat abnormal slow or fast heart rhythms in response to electrical signals within the heart.1

Ø Inhibition of pacing due to ventricular over sensing of EMI. Since these signals are interpreted by the device as R waves, no pacing is generated. This may result in profound bradycardia or asystole in a pacing-dependent patient.

ØMisinterpretation of EMI as a tachyarrhythmia, resulting in delivery of inappropriate shock(s) or anti-tachycardia pacing by an ICD.

ØDirect damage to the CIED, altering its ability to deliver treatment for ventricular tachycardias or pacing.

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·ICDs  are designed to treat life threatening arrhythmias and any EMI’s may be misinterpreted as a ventricular arrhythmia causing inappropriate initiation of anti-tachycardia therapy or delivery of shocks.

·Inappropriate shocks from an ICD are associated with increased mortality and hence it is avoided during surgery by magnet deactivation or re-programming.

·There is evidence that EMI is more likely to affect device function if it is used near the pulse generator or leads, typically, in surgeries superior to the umbilicus.

·We would like to present an interesting obstetric case with ICD in situ which was performed as per the updated British Heart Rhythm society guidelines. The recent guideline suggests that in surgical procedures below the umbilicus, it is reasonable not to carry out ICD deactivation/pacemaker reprogramming.