Serious outcomes among emergency department patients with presyncope: A systematic review

Syncope is transient loss of consciousness, and in presyncope, patients experience same prodromal symptoms without losing consciousness. While studies have extensively reported the risk of serious outcome among emergency department (ED) syncope, the outcome for patients with presyncope and their management are not well studied. We undertook a systematic review to assess the occurrence/identification of short-term (30-day) serious outcomes among ED patients with presyncope.

ED studies that enrolled patients with presyncope and reported any short-term serious outcome were included. Studies that enrolled patients without presyncope (e.g., hypoglycemia, seizure, and stroke) were excluded. We restricted our study to only English publications and searched the MEDLINE, Embase, Scopus, and Web of Science from the inception date to July 2023. We used SIGN 50 tool for assessment of risk of bias.

In total, 1788 articles were screened by two reviewers and 32 articles were selected for full-text assessment. Five (four prospective and one retrospective) studies with 2741 presyncope patients were included. Four studies were from North America and the fifth one was from Europe. Included studies had weaknesses due to risk of bias, but all had acceptable quality. The prevalence of overall adverse outcome varied 4.4%-26.8% for all adults and 5.5%-18.7% among older patients; arrhythmia was the most prevalent (17.4% in one study), followed by anemia/hemorrhage as reported in different studies. Among older patients, myocardial infarction was the third most common serious outcome reported in one study.

The prevalence of short-term serious outcomes varies from 4% to 27% among ED patients with presyncope in our review, with arrhythmia being the most common serious outcome. Our review indicates that presyncope may carry a similar risk to syncope, and hence, the same level of caution should be exercised for ED presyncope management as syncope.