Document Detail

Three cases of hypotension and syncope with ventricular pacing: possible role of atrial reflexes.
MedLine Citation:
PMID:  677029     Owner:  NLM     Status:  MEDLINE    
Hypotension with lightheadedness and near syncope occurred in three patients during effective ventricular pacing. Hemodynamic studies demonstrated a decrease in cardiac output ranging from almost no decrease to 15 percent, presumably related to the loss of effective atrial contraction. The decrease in output was too small to explain by itself the reduced blood pressure, which resulted from paradoxic reduction of total peripheral resistance in one patient and from failure of resistance to increase in two. Baroceptor reflexes (Valsalva response) were normal in all three patients; hence it is suggested that the failure of compensatory increases in total peripheral resistance may be due to a reflex from the sudden atrial distension that occurs during atrioventricular (A-V) dissociation. The fluctuations in arterial pressure during ventricular pacing were synchronous with the appearance of cannon waves in the right atrial pressure tracing. Arterial pressure during A-V dissociation thus appears to be balanced by two opposite reflexes: the baroceptor reflex, which attempts to compensate for reduction in output, and atrial distension, which reduces peripheral resistance.
C Alicandri; F M Fouad; R C Tarazi; L Castle; V Morant
Related Documents :
2551989 - Plasma concentrations of calcitonin gene-related peptide increase during haemodialysis:...
12097989 - Echocardiographic [correction of ehocardiographic] evaluation of regional left atrial f...
16798819 - Passive pericardial constraint protects against stretch-induced vulnerability to atrial...
2829109 - Atrial natriuretic factor: a hormone secreted by the heart.
2569319 - Atrial natriuretic factor: neuromodulator of the central nervous system regulation of b...
2146889 - Atrial natriuretic factor release and natriuresis in rats with high-output heart failure.
16110689 - Avp response to lbnp is attenuated in a hyperbaric environment.
7322959 - Comparison of the antihypertensive effects of indapamide and cyclopenthiazide.
11005119 - Automated cardiac output measurements by ultrasound are inaccurate at high cardiac outp...
Publication Detail:
Type:  Case Reports; Journal Article    
Journal Detail:
Title:  The American journal of cardiology     Volume:  42     ISSN:  0002-9149     ISO Abbreviation:  Am. J. Cardiol.     Publication Date:  1978 Jul 
Date Detail:
Created Date:  1978-09-25     Completed Date:  1978-09-25     Revised Date:  2007-11-15    
Medline Journal Info:
Nlm Unique ID:  0207277     Medline TA:  Am J Cardiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  137-42     Citation Subset:  AIM; IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Blood Pressure
Bradycardia / therapy
Cardiac Output
Cardiac Pacing, Artificial / adverse effects*
Heart Atria
Hypotension / etiology*
Middle Aged
Pacemaker, Artificial / adverse effects*
Syncope / etiology*
Vascular Resistance

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

Previous Document:  Remission of clinical angina pectoris: the Framingham study.
Next Document:  Cardiac sarcoidosis. Diagnosis with endomyocardial biopsy and treatment with corticosteroids.