Sinus Arrhythmia

I posted last week about my 25 week preemie (now 21 1/2 months) having a suspectd arrythmia.We had a holter done and EKG,blood work, etc and the cardiologist told us its just a normal sinus arrythmia.He said her heart looks and sounds strong.Ive been trying to explain what this is to my home nurses because thy have never heard of this and are still charting her as having an irregular hearbeat.Could you explain what a sinus arrythmia is so I can try to explain to them.Thank You

[Cleveland Clinic, MD]

Sinus arrhythmia is a normal "irregularity" of the heart due to many factors including the autonomic nervous system and respiration.  It is more pronounced in infants.  It is actually a  sign of good health and nothing to worry about.  To be honset with you it dosen't really matter if the nurses chart it as irregular as long as the doctor knows it's sinus arrhythmia.