[Syncope. A diagnostic challenge].

Approximately 40% of people have experienced a syncopal attack during their lifetime. If the possible causes of syncope are known, the variety of diagnostic procedures can be used efficiently. The European guidelines on the management of syncope recommend a structured diagnostic work-up and distinguish between initial and secondary diagnostic steps. With the basic diagnostic methods, true syncope can be differentiated from other non-syncopal conditions of loss of consciousness. With basic diagnostics it is possible to demonstrate clinical settings, which require emergency treatment, and unnecessary, expensive and time-consuming further diagnostics may be avoided. We provide an algorithm on how to proceed to determine the various reasons for syncope.