Child has been running a fever and now has abnormal heart beat.

About two weeks ago, my 18 month old daughter began running a fever.  Motrin would take it down for about 6 hours and it would be up again.  When the fever reached 103, I took her to the dr.  They checked her ears and swabbed her throat to check for strep and when all of that cleared the dr. said that it must be something viral and if the fever continued for more than two more days, bring her in for lab work.  Well, the fever stopped that day.  Until a couple of days ago.  Same scenerio.  She ran a fever for about 48 hours.  Then it stopped.  I had an 18 month appointment scheduled for today.  She developed a slight rash on her trunk.  The dr. said it was Roseola.  But more importantly, she had an irregular heart beat.  I asked a lot of questions but got pretty vague answers.  He said that it didn't sound like a murmur, more like the beat was fading out on the second beat.  He tried to explain something about how sometimes the valves split but I didn't understand.  I asked him if the fever could be because of an infection and also, if the fever could because there is bigger problem with her heart.  His answer was maybe to both questions.  

He told me to make an appointment for a month ahead for him to listen to it again.  I politely asked if there was anyway to do it sooner because I wouldn't be sleeping until I knew something and he changed it to two weeks.  

I guess I would just like to hear worst and best case scenerios, and how likely it is that this could be each of those things.  Would I be making a mistake to wait two weeks?  Could it be detrimental if there is some kind of heart defect?  

Any further information I could get would be wonderful!  

[Cleveland Clinic]

Rheumatic fever and/or endocarditis are the worst case scenarios.  In rheumatic fever which usually occurs after a bacterial streptococcal infection, the body forms antibodies against the valve and attacks it causing valve damage.  This is a process that occurs after about 2 weeks since the original infection and as far as I know can't be prevented unless the infection is treated early on.  Endocarditis is an infection of the heart valves which never gets better without therapy with IV antibiotics.  This is very unlikely in your situation.  The most likely explanation is that your child is fine and that there aren't any problems with his or her heart.  Skipped beats are common and may be brought on by infections or other metabolic processes associated with increased sympathetic tone.  I would probably get an EKG and maybe even an echo to make sure that everything is OK.  Bringing your child back to your doctor in about a months is probably appropriate as long as they are doing well and there aren't any new fevers or any limitations in terms of their exercise capacity.