Definitive aetiology of unexplained syncope after cardiovascular autonomic tests in a tertiary syncope unit
Author(s)
Torabi, Parisa
Hamrefors, Viktor
Sutton, Richard
Brignole, Michele
Fedorowski, Artur
Type
Journal Article
Abstract
Aims
Syncope is a common condition with many possible causes, ranging from benign to life-threatening aetiologies. Establishing a diagnosis can be difficult, and specialized syncope units, using cardiovascular autonomic tests (CATs), including a head-up tilt test, can increase the diagnostic yield. However, up to one-fifth of examined patients have inconclusive CAT results. The aim of the present study was to investigate the predictive value of history, and clinical findings for unexplained syncope after CAT and characterize the group with negative results.
Methods and results
Consecutive syncope patients [n = 2663, 61% women, median age 52 (32–69) years] were evaluated and CAT explained aetiology of syncope in 79% of cases, whereas 21% remained unexplained. Predictors of negative CAT were older age at first syncope (+8% higher odds per 10-year increment, P = 0.042), higher supine heart rate (HR; +12% per 10 b.p.m.; P = 0.003), absence of prodromes (+48%; P < 0.001), hypertension (+45%; P = 0.003), diabetes (+82%; P < 0.001), heart failure (+98%; P = 0.014), and coronary artery disease (+51%; P = 0.027). Compared with vasovagal syncope, patients with negative CAT were older, reported more often the absence of prodromes, and had a higher burden of cardiovascular comorbidities.
Conclusion
A cardiovascular autonomic test established the cause of syncope in 79% of patients evaluated in a syncope unit. Syncope without prodromes and cardiovascular comorbidities were significant predictors of failure to reveal an aetiology from assessment by CAT. These are known risk factors for cardiac syncope and patients with inconclusive CAT warrant further investigation.
Syncope is a common condition with many possible causes, ranging from benign to life-threatening aetiologies. Establishing a diagnosis can be difficult, and specialized syncope units, using cardiovascular autonomic tests (CATs), including a head-up tilt test, can increase the diagnostic yield. However, up to one-fifth of examined patients have inconclusive CAT results. The aim of the present study was to investigate the predictive value of history, and clinical findings for unexplained syncope after CAT and characterize the group with negative results.
Methods and results
Consecutive syncope patients [n = 2663, 61% women, median age 52 (32–69) years] were evaluated and CAT explained aetiology of syncope in 79% of cases, whereas 21% remained unexplained. Predictors of negative CAT were older age at first syncope (+8% higher odds per 10-year increment, P = 0.042), higher supine heart rate (HR; +12% per 10 b.p.m.; P = 0.003), absence of prodromes (+48%; P < 0.001), hypertension (+45%; P = 0.003), diabetes (+82%; P < 0.001), heart failure (+98%; P = 0.014), and coronary artery disease (+51%; P = 0.027). Compared with vasovagal syncope, patients with negative CAT were older, reported more often the absence of prodromes, and had a higher burden of cardiovascular comorbidities.
Conclusion
A cardiovascular autonomic test established the cause of syncope in 79% of patients evaluated in a syncope unit. Syncope without prodromes and cardiovascular comorbidities were significant predictors of failure to reveal an aetiology from assessment by CAT. These are known risk factors for cardiac syncope and patients with inconclusive CAT warrant further investigation.
Date Issued
2023-09-01
Date Acceptance
2023-08-13
Citation
Europace, 2023, 25 (9)
ISSN
1099-5129
Publisher
Oxford University Press
Journal / Book Title
Europace
Volume
25
Issue
9
Copyright Statement
© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology. This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial License (https://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact journals.permissions@oup.com
License URL
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/37589189
PII: 7243556
Subjects
AGE
Cardiac & Cardiovascular Systems
Cardiovascular autonomic tests
Cardiovascular System & Cardiology
DIAGNOSTIC YIELD
Head-up tilt test
Life Sciences & Biomedicine
OLDER
PATIENT
Science & Technology
Syncope
Unexplained syncope
VASOVAGAL SYNCOPE
Publication Status
Published
Coverage Spatial
England
Article Number
euad247
Date Publish Online
2023-08-17