Document Detail


ECG-triggered muscular counterpulsation for treatment of low cardiac output.
MedLine Citation:
PMID:  17551904     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
BACKGROUND: Skeletal muscular counterpulsation (MCP) has been used as a new noninvasive technique for treatment of low cardiac output. The MCP method is based on ECG-triggered skeletal muscle stimulation. The purpose of the present study was to evaluate acute hemodynamic changes induced by MCP in the experimental animal. METHODS: Eight anaesthetized pigs (43+/-4 kg) were studied at rest and after IV â-blockade (10 mg propranolol) before and after MCP. Muscular counterpulsation was performed on both thighs using trains (75 ms duration) of multiple biphasic electrical impulses with a width of 1 ms and a frequency of 200 Hz at low (10 V) and high (30 V) amplitude. ECG-triggering was used to synchronize stimulation to a given time point. LV pressure-volume relations were determined using the conductance catheter. After baseline measurements, MCP was carried out for 10 minutes at low and high stimulation amplitude. The optimal time point for MCP was determined from LV pressure-volume loops using different stimulation time points during systole and diastole. Best results were observed during end-systole and, therefore, this time point was used for stimulation. RESULTS: Under control conditions, MCP was associated with a significant decrease in pulmonary vascular resistance (-18%), a decrease in systemic vascular resistance (-11%) and stroke work index (-4%), whereas cardiac index (+2%) and ejection fraction (+6%) increased slightly. Pressure-volume loops showed a leftward shift with a decrease in end-systolic volume. After â-blockade, cardiac function decreased (HR, MAP, EF, dP/dt max), but it improved with skeletal muscle stimulation (HR +10% and CI +17%, EF +5%). There was a significant decrease in pulmonary (-19%) and systemic vascular resistance (-29%). CONCLUSIONS: In the animal model, ECG-triggered skeletal muscular counterpulsation is associated with a significant improvement in cardiac function at baseline and after IV â-blockade. Thus, MCP represents a new, non-invasive technique which improves cardiac function by diastolic compression of the peripheral arteries and veins, with a decrease in systemic vascular resistance and increase in cardiac output.
Authors:
B H Walpoth; C Aregger; L Lapanashvili; D Mettler; T Carrel; O M Hess
Related Documents :
7386394 - Comparative effects of catecholamines in cardiac tamponade: experimental and clinical s...
6480824 - Effects of acetyl glyceryl ether of phosphorylcholine (platelet activating factor) on v...
1115064 - Hemodynamic effects of staged hematocrit reduction in patients with stable cor pulmonal...
1884104 - Differential effects of (+/-)-dobutamine and human alpha-cgrp on cardiac and on regiona...
444174 - Central and cerebral hemodynamics and metabolism of the healthy man during head-down ti...
10678644 - A simplified method for monitoring respiratory impedance during continuous positive air...
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  The International journal of artificial organs     Volume:  30     ISSN:  0391-3988     ISO Abbreviation:  Int J Artif Organs     Publication Date:  2007 May 
Date Detail:
Created Date:  2007-06-06     Completed Date:  2007-10-16     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  7802649     Medline TA:  Int J Artif Organs     Country:  Italy    
Other Details:
Languages:  eng     Pagination:  407-14     Citation Subset:  IM    
Affiliation:
Swiss Cardiovascular Center, University Hospital Bern, Bern, Switzerland. beat.walpoth@hcuge.ch
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Blood Pressure
Cardiac Output, Low / physiopathology,  therapy*
Counterpulsation*
Electric Stimulation
Electrocardiography
Heart / physiopathology*
Heart Rate
Muscle, Skeletal
Stroke Volume
Sus scrofa
Vascular Resistance

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


Previous Document:  Plasma filtration on mediators of thrombotic microangiopathy: an in vitro study.
Next Document:  Enhancement of viability of muscle precursor cells on 3D scaffold in a perfusion bioreactor.