RESUMO
<p><b>OBJECTIVE</b>To understand the epidemiologic and clinical characteristics of the "Yunnan unknown-cause sudden cardiac death (YUSCD)".</p><p><b>METHODS</b>Cases of YUSCD occurred in 2002-2004 were investigated with cross-sectional study. Clinical manifestation was observed and analyzed.</p><p><b>RESULTS</b>The YUSCD areas were mountainous and most of the YUSCD cases appeared between June and August. Most of the YUSCD cases were young farmers and showed family/village clustering nature. Most of the patients died quickly with only few recovered. The overall incidence of YUSCD was 1.83% with mortality as 1.51%. The fatality rate of YUSCD appeared to be 78.1%.</p><p><b>CONCLUSION</b>The YUSCD cases had a clustering feature along with time and area. The clinical manifestation of YUSCD could not be specifically identified, making the clinical diagnosis and treatment difficult when practicing in the fields that called for further studies on epidemiology, clinical work and etiology.</p>