Selective use of diagnostic tests inpatients with XXXX of unknown cause.

@entity1 @entity944 @entity1163 @entity56 @entity299 @entity943
OBJECTIVE: We sought to prospectively assess the diagnostic yielding of a protocol in which electrophysiologic studies (EPS), tilt-table tests (TTTs), and loop recorder implantation are selectively used. BACKGROUND: The optimal strategy in the diagnosis of @entity1 with @entity1163 of unknown cause has not been defined. METHODS: A total of 184 consecutive @entity1 with @entity1163 of unknown cause were classified into two groups. Group A consisted of 72 @entity1 fulfilling any of the following criteria: 1) presence of structural @entity299 or family history of @entity944 ; 2) abnormal electrocardiogram; 3) significant non-symptomatic @entity943 on Holter monitoring; and 4) paroxysmal palpitations immediately before or after @entity1163 . These @entity1 initially underwent an EPS and, if this study was negative, TTT. In the remaining 112 @entity1 (group B), TTT was performed. RESULTS: The EPS was positive in 32 @entity1 (44%) in group A. The TTT was positive in 80 @entity1 (71%) in group B. An additional @entity1 had @entity56 . In @entity1 of group A with a negative EPS, the TTT was positive in 23 (57%). A loop recorder was implanted in 15 @entity1 from group A with negative conventional testing, and diagnostic activation was obtained in seven @entity1 . Overall, a positive diagnosis was achieved in 143 @entity1 (78%). CONCLUSIONS: In @entity1 with @entity1163 of unknown cause, selective use of EPS or TTT leads to a positive diagnosis in >70% of the cases. An implantable loop recorder can be useful in non-diagnosed cases.
