Document Detail

Electromechanical effects of cardiac resynchronization therapy during rest and stress in patients with heart failure.
MedLine Citation:
PMID:  17347041     Owner:  NLM     Status:  MEDLINE    
BACKGROUND: Haemodynamic and functional effects of cardiac resynchronization therapy (CRT) have been studied mostly at rest. CRT effects on left ventricular (LV) dyssynchrony and function during stress have not been evaluated in detail.
AIMS: We studied the electromechanical effects of CRT at rest and during Dobutamine stress echocardiography (DSE), during active and withheld CRT.
METHODS: Twenty-one responders to CRT (62+/-12 yr) were assessed by walking test, quality of life, and BNP with active CRT ("on") and 2 weeks after pacing withdrawal ("off"). DSE (10 microg/kg/min) was performed both at "on" and "off" to evaluate dyssynchrony parameters, systolic and diastolic function.
RESULTS: At rest, CRT withdrawal was associated with an increased interventricular mechanical delay (IVMD, from 21+/-18 ms to 49+/-24 ms, p<0.001) and impaired intraventricular synchrony. There was a significant decrease in LV systolic function and LV filling time. Dobutamine infusion had no impact on inter- and intraventricular synchrony. During stress, there was an improvement in LV performance both at "on" and "off". However, LV dp/dt, aortic VTI, cardiac output, mean systolic peak velocities and LV filling time during dobutamine stress were significantly greater with CRT "on".
CONCLUSION: In long-term responders, CRT improves LV performance both at rest and during dobutamine stress. This is attributable to an improvement in LV synchrony, which is maintained during stress.
Cinzia Valzania; Fredrik Gadler; Maria J Eriksson; Arne Olsson; Giuseppe Boriani; Frieder Braunschweig
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2007-03-07
Journal Detail:
Title:  European journal of heart failure     Volume:  9     ISSN:  1388-9842     ISO Abbreviation:  Eur. J. Heart Fail.     Publication Date:    2007 Jun-Jul
Date Detail:
Created Date:  2007-05-14     Completed Date:  2007-08-17     Revised Date:  2011-06-08    
Medline Journal Info:
Nlm Unique ID:  100887595     Medline TA:  Eur J Heart Fail     Country:  Netherlands    
Other Details:
Languages:  eng     Pagination:  644-50     Citation Subset:  IM    
Institute of Cardiology of the University of Bologna, Bologna, Italy. <>
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MeSH Terms
Cardiac Output / physiology
Cardiac Pacing, Artificial*
Diastole / physiology
Echocardiography, Doppler
Echocardiography, Doppler, Pulsed
Echocardiography, Stress*
Heart Failure / physiopathology*,  therapy
Middle Aged
Natriuretic Peptide, Brain / blood
Rest / physiology
Stroke Volume / physiology
Systole / physiology
Treatment Outcome
Ventricular Dysfunction, Left / physiopathology*,  therapy
Ventricular Function, Left / physiology
Reg. No./Substance:
114471-18-0/Natriuretic Peptide, Brain

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

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