Here is a 76 year old patient who was admitted for a noncardiac cause. During her hospital course she was admitted to the ICU. It was than decided she needed a Swan Ganz Catheter. EKG's were taken before and after placement of the catheter. What has happened?

Click here for clearer image of EKG

EKG before placement

Click here for clearer image of EKG

EKG after procedure.

What has happened? The first EKG has evidence for old inferior infarct, a leftward axis and possible left atrial abnormality. However the following ekg right after the procedure has a RBBB present that was not there before and was never present on any recorded EKG's. What happened here is what can sometimes occur when placing a swan ganz catheter. The guidewire when passed throught the RA, than RV can hit the moderator band located the right ventricle. With in the moderator band runs the Right bundle branch of the perkinje system which delivers the impulse to the free wall of the RV. By knicking the moderator band we temporarily knocked out the the Right bundle leading to the presence of this. What made the patient more succeptable to this is the presents of an old inferior MI due to the fact that most of the time the Right Coronary supplies the inferior aspect of the heart which also supplies the moderator band. It subsequently resolved and never returned.