Had 14 day loop and had sinus tachycardia with heart rates 55-180bpm. Also the 180 occurs when sleeping or lying in bed. Cardiologist not sure why tach occurs every night. Elevated epinephrine? Ideas?

Tachycardia . I recommend you to see an electrophysiologist , you maybe having inappropriate sinus tachycardia, focal atrial tachycardia besides possibility of normal rhythm acceleration. You can consult me also if you have ECG Holter echo results ..www.healthtap.com/volkantuzcu .
Tachycardia. Did the cardiologist state what type of tachycardia the rhythm of 180 beats per minute was? Supraventricular or ventricular and how long these tachyarrhythmias lasted?Anxiety usually doesn't cause the heart to beat at 180/min. Checking for hyperthyroidism and for a pheochromocytoma would be advisable before attributing these episodes to anxiety reactions panic attacks. ?See an endocrinologist.