Diagnostic value of history in patients with syncope with or without heartdisease

OBJECTIVES We sought to establish what historical findings are predictive o f the cause of syncope. BACKGROUND The clinical features of the various types of syncope have not b een systematically investigated. METHODS Three hundred forty-one patients with syncope were prospectively ev aluated. Each patient was interviewed using a standard questionnaire. A cau se of syncope was assigned using standardized diagnostic criteria. RESULTS A cardiac cause of syncope was established in 23% of the patients, a neurally mediated cause in 58% and a neurologic or psychiatric cause in 1 %, and in the remaining 18%, the cause of syncope remained unexplained. In a preliminary analysis including age, gender and the presence of suspected or certain heart disease after the initial evaluation, only heart disease w as an independent predictor of a cardiac cause of syncope (odds ratio 16, p = 0.00001), with a sensitivity of 95% and a specificity of 45%. In contras t, the absence of heart disease allowed us to exclude a cardiac cause of sy ncope in 97% of the patients. In patients with certain or suspected heart d isease, the most specific predictors of a cardiac cause were syncope in the supine position or during effort, blurred vision and convulsive syncope. S ignificant and specific predictors of a neurally mediated cause were time b etween the first and last syncopal episode >4 years, abdominal discomfort b efore the loss of consciousness and nausea and diaphoresis during the recov ery phase. In the patients without heart disease, palpitation was the only significant predictor of a cardiac cause. CONCLUSIONS The presence of suspected or certain heart disease after the in itial evaluation is a strong predictor of a cardiac cause of syncope. A few historical findings are useful to predict cardiac and neurally mediated sy ncope in patients with and without heart disease. (J Am Coll Cardiol 2001;3 7:1921-8) (C) 2001 by the American College of Cardiology.