Carotid sinus syncope: the most frequent neurally mediated syncope in the elderly

The present work reviews current literature and the authors' experience of carotid sinus syndrome (CSS), which is considered to be the most common cause of neurally mediated acute disorders of consciousness in the elderly. Although no definitive consensus about its nosology has yet been reached, most groups agree that three features fulfill the diagnosis: anamnestic presence of syncope or its minor equivalents, and their reproduction by carotid sinus massage associated with defined values of cardioinhibition or vasodepression or both. The technique for performing carotid sinus massage used by the authors is described; this manoeuvre seems very safe and reproducible as long as simple rules are followed, and it allows the classification of CSS types. The treatment of CSS is varied, according to several factors. No pharmacological therapy has yet been demonstrated to be effective. While severe cardioinhibitory forms require an appropriate pacing, vasodepressive ones and types with only minor symptoms show a more favourable natural history. Pacing is advised in mixed CSS with either frequent and invalidating relapses, or 'high risk' attacks (severe, abrupt, with major traumas, etc.). Finally, the protocol for choosing the adequate mode of pacing is illustrated. In most cases VVI is sufficient, but the decision requires a careful individual examination.