Document Detail


Vasodepressor syncope due to subclinical myocardial ischemia.
MedLine Citation:
PMID:  9048251     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
INTRODUCTION: Vasodepressor syncope is a common cause of syncope, but the initiating event that triggers the vasodepressor response remains incompletely understood. Although ischemia due to acute right coronary occlusion may precipitate hypotension and bradycardia through the Bezold-Jarisch reflex, an ischemic precipitant for the common vasodepressor faint has not been previously identified. In the present study, we present evidence for a causal relationship between myocardial ischemia and vasodepressor syncope. METHODS AND RESULTS: Two patients referred for evaluation of syncope underwent upright tilt table testing with either ST segment monitoring, sestamibi scintigraphy and echocardiography during the tilt test, or coronary angiography. Both patients had positive tilt table tests during the control study. Patient 1 was documented to have reproducible ischemic ECG changes during atypical chest pressure induced by upright tilt, despite a normal coronary angiogram with ergonovine provocation. Subsequent tilt testing with simultaneous sestamibi perfusion imaging and echocardiography revealed reversible anterolateral hypoperfusion corresponding with anterolateral hypokinesis during upright tilt that preceded syncope. Ischemic ECG changes during incremental rapid atrial pacing further suggested ischemia on the basis of microvascular disease. Follow-up tilt testing on verapamil was negative. Patient 2 developed ischemic ECG changes during the recovery phase of an exercise stress test, which was followed by a vasodepressor response and frank syncope. Coronary angiography revealed a 90% distal right coronary artery stenosis that was successfully dilated, after which follow-up tilt table testing off all other medication was negative. CONCLUSIONS: These two cases illustrate a previously unrecognized causality between myocardial ischemia and clinical vasodepressor syncope, and demonstrate that subtle manifestations of myocardial ischemia, associated with either atypical angina or silent ischemia, can provoke syncope.
Authors:
D D Ascheim; S M Markowitz; H Lai; E D Engelstein; K M Stein; B B Lerman
Publication Detail:
Type:  Case Reports; Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Journal of cardiovascular electrophysiology     Volume:  8     ISSN:  1045-3873     ISO Abbreviation:  J. Cardiovasc. Electrophysiol.     Publication Date:  1997 Feb 
Date Detail:
Created Date:  1997-05-15     Completed Date:  1997-05-15     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  9010756     Medline TA:  J Cardiovasc Electrophysiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  215-21     Citation Subset:  IM    
Affiliation:
Department of Medicine, New York Hospital--Cornell Medical Center, New York 10021, USA.
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MeSH Terms
Descriptor/Qualifier:
Cardiac Pacing, Artificial
Coronary Angiography
Electrocardiography
Exercise Test
Female
Humans
Male
Middle Aged
Myocardial Ischemia / complications*
Syncope, Vasovagal / etiology*,  physiopathology
Tilt-Table Test
Tomography, Emission-Computed, Single-Photon
Grant Support
ID/Acronym/Agency:
R01-44747//PHS HHS

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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