The holter helps to detect abnormal heart rhythms. A holter is used for the evaluation of giddiness or loss of consciousness which were not picked up on a routine ECG. The holter is a wearable device which is used to record your heart rhythm for 24, 48, 72 hours or 7, 14, 28 days as required. Once your doctor has hooked up a holter, you can go home and do all the routine activities including going for work or heavy activities. The holter increases the chances of picking up atrial fibrillation, ventricular tachycardia and Brady arrhythmias.