Ask the doctor: Is it okay to have an MRI after getting a stent?

Q. I needed angioplasty in 2007 and had a stent implanted during the procedure. Due to another health problem, my doctor now wants me to have an MRI. Could this cause any problem with the stent?

A. Stents are metallic cages that hold open a coronary artery after angioplasty. Metallic objects placed in the body can pose problems for MRI scans, which use a strong magnetic field and pulses of radio waves to see inside the body. The magnetic field could dislodge the object, while radio waves could make it heat up. That kind of movement and heating has been reported for some cardiac pacemakers and implantable cardioverter-defibrillators. (MRI-safe pacemakers and implantable cardioverter-defibrillators are being developed.)