Conductance artifacts in a novel in vitro model of ventriculothoracic electrical coupling. ASAIO J 1999 Jan-Feb;45(1):64-8
Date
02/10/1999Pubmed ID
9952010DOI
10.1097/00002480-199901000-00015Scopus ID
2-s2.0-0032601376 3 CitationsAbstract
The utility of open chest conductance (COND) ventriculography is limited by artifacts altering the relationship between COND and left ventricular (LV) volume. Pressure-COND loops often lean to the left during LV volume reduction by caval occlusion. Time varying alterations in the pericardial-LV contact area affect electrical coupling in the open chest during the cardiac cycle, producing COND artifacts. In this study, an open-mediastinum model was constructed. Components represented the LV, blood, pericardium, and thoracic contents. Varying ventriculothoracic coupling was simulated by changing the volume of pericardial saline (0, 30, 60 ml). Raw dual field COND was repeatedly (n = 20) compared with volumes of normal saline from 60 to 120 ml at 5 ml intervals. Groups were compared by linear regression and repeated measures ANOVA. Artifacts significantly (p < 0.01) altered parallel COND, indicated by the y-intercept, with the exception of 0 versus 30 ml. The slope constant also changed significantly, with the exception of 30 versus 60 ml. These results suggest that variable pericardial-LV contact can cause time varying artifacts in COND in the open chest. Therefore, posterior insulation may reduce artifacts in COND ventriculography and should be tested for this effect.
Author List
Hart JP, Cabreriza SE, Dean DA, Jia CX, Spotnitz HMAuthor
Joseph Hart MD Associate Professor in the Surgery department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Analysis of VarianceAnimals
Artifacts
Cardiac Volume
Cattle
Electric Conductivity
Heart Function Tests
Models, Cardiovascular
Regression Analysis
Reproducibility of Results
Ventricular Function, Left
