Mechanisms of Early Filling in the Left Ventricle

Urroz Lopez, Maryell Giofred

Mechanisms of Early Filling in the Left Ventricle

dc.contributor.advisor	Tyberg, John V. T.
dc.contributor.advisor	Shrive, Nigel Graham
dc.contributor.author	Urroz Lopez, Maryell Giofred
dc.contributor.committeemember	Belenkie, Israel
dc.contributor.committeemember	Sheldon, Robert Stanley
dc.contributor.committeemember	Fewell, James E.
dc.date	2021-02
dc.date.accessioned	2021-01-25T19:39:46Z
dc.date.available	2021-01-25T19:39:46Z
dc.date.issued	2021-01-08
dc.description.abstract	The mechanism by which ventricular filling occurs has been debated for centuries. Originally, it was believed that ventricular filling was an entirely passive process. However, in the 20th-century, researchers proposed that LV played a role in its own filling sucking blood into itself. At the early phase of diastole, the LV enlarges faster than it is able to fill passively by the Left Atrium (LA); therefore, aspirating blood into itself. Diastolic suction (DS) is the term applied to the phenomenon whereby the left ventricle (our study will be limited to the LV), in part, fills itself. Two approaches to study DS are the volume of filling due to suction, VDS (Katz’ approach), and the energy of the Backward Decompression Wave, BDW (Wang’s approach). Our first aim was to determine if DS exists at LV volumes that exceed the unstressed volume. Our second aim was to compare Katz’ Criterion to the energy of the BDW generated by the LV (Wang’s approach). The study was performed using a porcine model. Hemodynamics and mitral blood flow velocity were measured over a range of filling pressures during baseline, inferior vena cava occlusion (IVCO), and volume loading. Our findings suggests that the LV generates suction when ESV is greater than ESV at baseline (ESVB), which opposes the view that the LV is not capable of generating suction at increasing ESV’s. We found non-zero values of VDS and IW-DS when ESV>ESVB which suggest a non-recoil mechanism responsible for suction. In addition, our data shows that both approaches to DS, measured by VDS and IW-DS, are indeed related as they responded in the same manner to changes in EDV, ESV, and EDP.	en_US
dc.identifier.citation	Urroz Lopez, M. G. (2021). Mechanisms of Early Filling in the Left Ventricle (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.	en_US
dc.identifier.doi	http://dx.doi.org/10.11575/PRISM/38576
dc.identifier.uri	http://hdl.handle.net/1880/113008
dc.language.iso	eng	en_US
dc.publisher.faculty	Cumming School of Medicine	en_US
dc.publisher.institution	University of Calgary	en
dc.rights	University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.	en_US
dc.subject	Diastolic Suction	en_US
dc.subject	Early Left Ventricular Filling	en_US
dc.subject.classification	Physiology	en_US
dc.title	Mechanisms of Early Filling in the Left Ventricle	en_US
dc.type	master thesis	en_US
thesis.degree.discipline	Medicine – Cardiovascular/Respiratory Science	en_US
thesis.degree.grantor	University of Calgary	en_US
thesis.degree.name	Master of Science (MSc)	en_US
ucalgary.item.requestcopy	true	en_US