liu.seSök publikationer i DiVA
Ändra sökning
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Flow patterns in the aortic root and the aorta studied with time-resolved, 3-dimensional, phase-contrast magnetic resonance imaging: implications for aortic valve–sparing surgery
Linköpings universitet, Institutionen för medicin och vård, Klinisk fysiologi. Linköpings universitet, Hälsouniversitetet.
Linköpings universitet, Institutionen för medicin och vård, Klinisk fysiologi. Linköpings universitet, Hälsouniversitetet.ORCID-id: 0000-0003-1395-8296
Linköpings universitet, Institutionen för medicin och vård, Klinisk fysiologi. Linköpings universitet, Hälsouniversitetet.
Linköpings universitet, Institutionen för medicin och vård, Klinisk fysiologi. Linköpings universitet, Hälsouniversitetet.
Visa övriga samt affilieringar
2004 (Engelska)Ingår i: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 127, nr 6, s. 1602-1607Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Objective

Sparing the aortic valve has become a surgical option for patients who require repair of aortic root ectasia and have normal valve leaflets. Surgical approaches to valve sparing differ with regard to preservation of the native sinuses of Valsalva. The role of the sinuses and the importance of maintaining them remain controversial.

Methods

By using a time-resolved, 3-dimensional, phase-contrast magnetic resonance imaging technique, aortic root and aortic blood velocity data were acquired from 2 patients with Marfan syndrome 6 months after aortic valve–sparing surgery with straight Dacron grafts and contrasted with data from 6 normal volunteers.

Results

In normal aortas vortical blood flow became apparent in the individual sinuses after peak systole. The vortices filled the available space behind the valve leaflets and persisted until diastole, expanding and moving inward during aortic valve closure. In contrast, no vortices were observed in the postoperative patients with Marfan syndrome with negligible sinuses.

Conclusions

Changes in supravalvular flow accompany loss of sinus architecture. Whether the presence, size, and velocity of supravalvular vortices affects the function or durability of the preserved aortic valve remains to be studied.

Ort, förlag, år, upplaga, sidor
2004. Vol. 127, nr 6, s. 1602-1607
Nationell ämneskategori
Medicin och hälsovetenskap
Identifikatorer
URN: urn:nbn:se:liu:diva-24305DOI: 10.1016/j.jtcvs.2003.10.042Lokalt ID: 3927OAI: oai:DiVA.org:liu-24305DiVA, id: diva2:244622
Tillgänglig från: 2009-10-07 Skapad: 2009-10-07 Senast uppdaterad: 2017-12-13
Ingår i avhandling
1. Quantification of cardiovascular flow and motion: aspects of regional myocardial function and flow patterns in the aortic root and the aorta
Öppna denna publikation i ny flik eller fönster >>Quantification of cardiovascular flow and motion: aspects of regional myocardial function and flow patterns in the aortic root and the aorta
2004 (Engelska)Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
Abstract [en]

Quantification of cardiovascular flow and motion is essential in the diagnosis, treatment and follow-up of cardiovascular disease. The accuracy and quantification of many imaging methods used in this field have important shortfalls, however, that result from limitations in spatial and temporal dimensions. Improvement in application of these methods requires an in-depth understanding of the technical and perceptual aspects that contribute to errors in their use.

Visual assessment of echocardiographic images for asynchrony in regional myocardial motion during systolic contraction is an example of the need for better definition of limitations. The discernible delay in wall motion improved from 89 ms to 71 ms by allowing side-by-side comparison to normal motion. Clinically important delays are almost certainly missed with current "eyeballing" methods. Different and more quantitative approaches to this problem have been developed. Anatomic M-mode (AMM) assesses motion along an arbitrary line within a two-dimensional (2D) image, and was demonstrably robust in the clinical setting when used with second harmonic imaging at a depth less than 20 cm and with angle correction ofless than 60°. Doppler myocardial (DMI) imaging and strain rate imaging (SRI) were also shown to reliably demonstrate the effects of inotropic stimulation, total and severe ischemia on asynchrony in a closed chest pig model. Quantification of the changes induced by inotropy and total ischemia was possible with both methods, but the effects of stunning were not. Regional myocardial function and cardiovascular flow can also be assessed with time-resolved, three-directional, three-dimensional (3D) velocity data acquired using phase contrast magnetic resonance imaging (PC-MRI). This multidimensional data demonstrated longitudinal velocity gradients along all four walls of the left ventricle, with miuirnal apical longitudinal motion. The 3D velocity vector from single points in the ventricular wall shows that the motion over the cardiac cycle is complex in all dimensions. The flow patterns in the aortic root were also studied using time-resolved 3D PC-MRI in normal volunteers and patients who had undergone aortic-valve sparing surgery using straight Dacron grafts. In normals, vortices appeared in the sinuses of Valsalva in late systole, increased in size with the deceleration of aortic outflow and moved together as the valve closed in early diastole. These normal flow structures have never before been demonstrated in three dimensions in man. In the postoperative patients, lacking both sinuses and sinotubular junction, vortices were not observed.

Many imaging methods can be improved by a critical definition of the limits oftheir reliability. This can prompt the modifications and new methods which allow us to move beyond the original shortcomings and contribute new knowledge regarding the pathophysiology of cardiovascular disease.

Ort, förlag, år, upplaga, sidor
Linköping: Linköpings universitet, 2004. s. 63
Serie
Linköping University Medical Dissertations, ISSN 0345-0082 ; 832
Nationell ämneskategori
Medicin och hälsovetenskap
Identifikatorer
urn:nbn:se:liu:diva-24209 (URN)3803 (Lokalt ID)91-7373-804-2 (ISBN)3803 (Arkivnummer)3803 (OAI)
Disputation
2004-02-20, Elsa Brändströmssalen, Universitetssjukhuset, Linköping, 13:00 (Svenska)
Opponent
Tillgänglig från: 2009-10-07 Skapad: 2009-10-07 Senast uppdaterad: 2012-10-29Bibliografiskt granskad

Open Access i DiVA

Fulltext saknas i DiVA

Övriga länkar

Förlagets fulltext

Personposter BETA

Escobar Kvitting, John-PederEbbers, TinoWigström, LarsEngvall, Jan

Sök vidare i DiVA

Av författaren/redaktören
Escobar Kvitting, John-PederEbbers, TinoWigström, LarsEngvall, Jan
Av organisationen
Klinisk fysiologiHälsouniversitetetThoraxkirurgi
I samma tidskrift
Journal of Thoracic and Cardiovascular Surgery
Medicin och hälsovetenskap

Sök vidare utanför DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetricpoäng

doi
urn-nbn
Totalt: 228 träffar
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf