Single center experience in Japanese patients with syncope

Area of Science:

• Cardiology
• Neurology
• Internal Medicine

Background:

• Syncope diagnosis methods and characteristics in Japan were previously unclear.
• Head-up tilt tests and implantable loop recorders (ILRs) are recent advancements for syncope diagnosis.
• Diagnostic approaches and success rates for syncope can vary significantly.

Purpose of the Study:

• To elucidate current syncope diagnostic methods and features at a single Japanese medical center.
• To compare the effectiveness of different diagnostic tools for various syncope etiologies.
• To assess the utility of ILRs in diagnosing unexplained syncope.

Main Methods:

• Retrospective review of 547 syncope patients from January 2009 to December 2012.
• Analysis of initial and early diagnostic evaluations, including situational syncope and orthostatic hypotension.
• Evaluation of implantable loop recorder (ILR) implantation rates and diagnostic yield in unexplained syncope cases.

Main Results:

• Cardiac syncope was the most frequent diagnosis (34.0%), followed by reflex syncope (29.1%) and unexplained syncope (23.9%).
• Situational syncope and orthostatic hypotension were more often diagnosed during initial evaluations.
• ILR implantation had a 53.1% consent rate in unexplained syncope; cumulative diagnostic rates were 47% at 1 year and 65% at 2 years, outperforming conventional tests.

Conclusions:

• Syncope in Japan stems from diverse causes, necessitating an understanding of each etiology's characteristics.
• The low consent rate for ILR implantation in unexplained syncope highlights a need for patient education on diagnostic importance.
• ILR use significantly enhances diagnostic rates for unexplained syncope, leading to reduced symptom recurrence.