Malignant Vasovagal Syncope: Physiopathology, Diagnosis, Epidemiology, and Medical Treatment

The encouraging results from the "Inotropy Controlled Pacing in Vasovagal Syncope" (INVASY) Italian multicenter clinical trial – which demonstrated the effectiveness of pacing based on Closed Loop Stimulation (CLS, Biotronik, Germany) in preventing vasovagal syncope (VVS) [1,2] – provided us incentive to prepare a review entitled "Malignant Vasovagal Syncope." The review provides an updated review of topics related to VVS and efforts made by the medical community and biomedical industry to find effective therapeutic solutions for it. The contents of the review will be divided into two parts. This present first part addresses clinical aspects and medical treatment of VVS. The second part, to be published in the December issue of this journal, will analyze the clinical benefit of conventional cardiac pacing (and of its special form CLS), compare the efficacy of all available therapies, and draw conclusions. Physiopathology of VVS