From the article's graphic that states:
Jewelry With a PurposeFirst, if the patient needs a shock to correct a heart rhythm disturnance, pacemakers and defibrillators are engineered so this will not hurt the circuitry of the devices. Treatment with medications or shock therapy should not be delayed, if indicated, in people with these devices should it be necessary.
Medical alert bracelets and other identification systems are important for notifying emergency responders about medical conditions. Here's what could go wrong in some situations if a patient isn't wearing one:
If a patient has...
Pacemaker or implanted defibrillator
Medics may mistakenly treat with drugs for heart arrhythmia or try to shock the patient.
Secondly, if you have a medical alert bracelet that notes that you have a pacemaker or defibrillator, consider adding the name of the manufacturer to the bracelet, since the machinery to program the device is specific to each manufacturer's device and this information can speed your treatment should the device need to be interrogated or adjusted.