An<unk>  evaluation strategy of taking a detailed history, physical examination, risk stratification, ECG recording and BP measurement should help decide what investigations should be ordered (based on whether the syncope is cardiac related, reflex/neutrally mediated, secondary to cerebrovascular disease or due to orthostatic hypotension).
Paroxysmal AV block Initial Approach
Paroxysmal AV block Acute Management
Paroxysmal AV block Cardiac Pacing
Paroxysmal AV block Implantable Loop Recorder
Paroxysmal AV block Electrophysiologic studies
Paroxysmal AV block Treatment for Reflex Syncope
Pulseless ventricular tachycardia interventions
Third degree AV block MRI