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Three-dimensional assessment of cardiac function; When right is wrong

Ostenfeld, Ellen LU (2014) In Lund University, Faculty of Medicine Doctoral Dissertation Series 2014:33.
Abstract (Swedish)
Popular Abstract in Swedish

Bedömning av höger sida av hjärtat är viktig hos patienter med hjärtsjukdom; i synnerhet hos patienter med förhöjt tryck i lungkretsloppet. Sänkt högerkammarfunktion och förhöjt tryck i höger förmak har visats vara prognostiskt dåligt. Två-dimensionellt ultraljud av hjärtat (ekokardiografi) är den vanligaste metoden för att bedöma hjärtats funktion, men högerkammaren är svår att värdera med denna metod. Detta beror delvis på att en 2-dimensionell metod har inneboende problem att värdera en 3-dimensionellt komplicerad struktur som den högra sidan av hjärtat. Magnetresonans av hjärtat och 3-dimensionell (3D) ekokardiografi kan användas för avbildning i tre dimensioner.

Syftet med denna... (More)
Popular Abstract in Swedish

Bedömning av höger sida av hjärtat är viktig hos patienter med hjärtsjukdom; i synnerhet hos patienter med förhöjt tryck i lungkretsloppet. Sänkt högerkammarfunktion och förhöjt tryck i höger förmak har visats vara prognostiskt dåligt. Två-dimensionellt ultraljud av hjärtat (ekokardiografi) är den vanligaste metoden för att bedöma hjärtats funktion, men högerkammaren är svår att värdera med denna metod. Detta beror delvis på att en 2-dimensionell metod har inneboende problem att värdera en 3-dimensionellt komplicerad struktur som den högra sidan av hjärtat. Magnetresonans av hjärtat och 3-dimensionell (3D) ekokardiografi kan användas för avbildning i tre dimensioner.

Syftet med denna avhandling är att värdera hur 3D-ekokardiografi och magnetresonans av hjärtat kan användas för att bestämma höger hjärthalvas funktion; och även bestämma hur hjärtats pumpfysiologi påverkas vid förhöjt tryck i höger förmak och förhöjt tryck i lungkretsloppet. I avhandlingen används för utvärdering både 2D och 3D teknik med ekokardiografi samt magnetresonans.

Delarbete I visade hur man bäst utför och samlar in 3D-ekokardiografiska data för volymbedömning av både förmak och kammare. Studien visade att en insamlingsteknik från spetsen av hjärtat (apikal teknik) bör användas vid volymbedömning med 3D-ekokardiografi, och att man ibland behöver en justerad vinkel jämfört med 2D. Medan förmaken och vänster kammare visualiserades väl, var höger kammare en utmaning.

Delarbete II validerade högerkammarens volymer och funktion hos en vuxen kardiologisk population med 3D-ekokardiografi där magnetresonans var referensmetod. Studien visade hur svårt det är att använda 3D-ekokardiografi för på högerkammarvärdering i en kliniskt oselekterad population. Dessutom visade studien att relativt många manuella korrektioner måste göras för att få värden som är någorlunda hållbara, när man jämför mätningarna med magnetresonans.

Delarbete III bedömde förhöjt höger förmakstryck genom att kvantifiera höger förmaksvolymer med 3D-ekokardiografi hos patienter med förhöjt tryck i lungkretsloppet. Volymerna jämfördes med invasivt mätta tryckvärden och mot magnetresonans. Studien visade att 3D-ekokardiografi men även 2D- ekokardiografiska estimat av höger förmaksvolymer var bättre än gängse ekokardiografiska metoder för att bedöma förhöjt medeltryck i höger förmak, även om ekokardiografi underskattade volymerna väsentligen jämfört med magnetresonans.

Delarbete IV undersökte bidraget till slagvolym från longitudinell, lateral och septal pumpfunktion i höger och vänster kammares hos patienter med förhöjda tryck i lungkretsloppet. De olika komponenterna jämfördes med en frisk normalpopulation. Magnetresonans användes med tanke på resultaten i delarbete II och trycket mättes med en kateter i höger hjärthalva. Studien visade att den longitudinella (längsgående) och det laterala (kramande) tillskottet till vänster kammares slagvolym är påverkade hos patienter med förhöjt tryck i lungkretsloppet jämfört med friska. Höger kammares längsgående och kramande tillskott till slagvolymen skiljer sig dock inte mellan patienter och friska. Skiljeväggen mellan kamrarna (septum) rör sig i båda grupperna mot vänster, men i lägre grad hos patienterna än friska. De olika komponenterna till pumpfunktion skiljer sig hos patienter med förhöjt tryck i lungkretsloppet jämfört med patienter med volymbelastad högerkammare. Detta ger ny information för att förstå hjärtats pumpfysiologi. (Less)
Abstract
Assessment of the right side of the heart is important in patients with heart disease; especially in patient with elevated pressure in the lung circulation. Decreased right ventricular function and elevated pressure in the right atrium are of poor prognostic value. Two-dimensional echocardiography (ultrasound of the heart) is the most commonly used method to assess the hearts function, but the right ventricle is hard to assess with this method. This is partly due to a 2-dimensional method has intrinsic problems to assess a 3-dimensional complex structure such as the right side of the heart. Magnetic resonance imaging of the heart and 3-dimensional (3D) echocardiography can be used for imaging in three dimensions.

The aim of this... (More)
Assessment of the right side of the heart is important in patients with heart disease; especially in patient with elevated pressure in the lung circulation. Decreased right ventricular function and elevated pressure in the right atrium are of poor prognostic value. Two-dimensional echocardiography (ultrasound of the heart) is the most commonly used method to assess the hearts function, but the right ventricle is hard to assess with this method. This is partly due to a 2-dimensional method has intrinsic problems to assess a 3-dimensional complex structure such as the right side of the heart. Magnetic resonance imaging of the heart and 3-dimensional (3D) echocardiography can be used for imaging in three dimensions.

The aim of this thesis is to assess how 3D echocardiography and magnetic resonance imaging of the heart can be used to determine the right heart function; and due to this determine how the heart pump physiology is altered by elevated right atrial and pulmonary pressure. In this thesis, echocardiography and magnetic resonance imaging is used with 2D and 3D technique.

Study I showed how to acquire 3D echocardiography for volume assessment of both atria and ventricles in adult cardiac patients. Acquisition from the apex of the heart, with at times an 'off-axis' approach, should be used for volumetric assessment with 3D echocardiography. While the atria and the left ventricle were well visualized, the right ventricle was a challenge.

Study II aimed to validated right ventricular volumes and function, in a population of adult cardiac patients, with 3D echocardiography using magnetic resonance imaging as a reference. The study showed the difficulty to asses right ventricular volumes and function, even when using 3D echocardiography in a clinically unselected population. Furthermore, the study showed the importance of manual corrections to achieve reasonably valid measurements, when compared to magnetic resonance imaging.

Study III assessed elevated right atrial pressure by quantifying right atrial volumes with 3D echocardiography in patients with elevated pressure in the lung circulation. The volumes were compared to invasively measured pressure values and magnetic resonance imaging. The study showed that 3D as well as 2D echocardiographic volume assessment of the right atrium were better than the conventional echocardiographic methods to determine elevated right atrial pressure. This was despite a substantial underestimation of the 3D echocardiographic volumes compared to magnetic resonance imaging.

Study IV examined the different contributions to right and left ventricular stroke volume in patients with elevated pressure in the lung circulation; and compared to those of healthy adults. Magnetic resonance imaging was used given the results of study II and pressure was quantified by right sided catheterization. The study showed that longitudinal and lateral contribution to left ventricular stroke volume was altered in patients with elevated pressure in the lung circulation compared to the control group. Right ventricular longitudinal and lateral contribution to stroke volume did not differ between patients and controls. The septum moved to the left in both groups, however less in patients than in healthy adults. In patients with elevated pressure in the lung circulation and hence pressure loaded right ventricles, the different components of pump function are altered in a different compared to volume loaded right ventricles. This is new information that helps understand the hearts physiology. (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • MD, PhD, Professor Flachskampf, Frank, Uppsala University, Uppsala, Sweden
organization
publishing date
type
Thesis
publication status
published
subject
keywords
Key words Three-dimensional echocardiography, cardiac magnetic resonance imaging, cardiac function, volumes, atria, ventricles, pulmonary hypertension, right heart catheterization, right ventricular pressure load.
in
Lund University, Faculty of Medicine Doctoral Dissertation Series
volume
2014:33
pages
142 pages
publisher
Department of Clinical Physiology, Lund University
defense location
Föreläsningssalen vid Strålbehandlingen, Skåne Onkologiska Klinik, Lund.
defense date
2014-03-07 13:00
ISSN
1652-8220
ISBN
978-91-87651-57-1
language
English
LU publication?
yes
id
38a676ce-8201-4305-9318-dfe5a5497a40 (old id 4293941)
date added to LUP
2014-02-11 10:43:38
date last changed
2016-09-19 08:44:49
@phdthesis{38a676ce-8201-4305-9318-dfe5a5497a40,
  abstract     = {Assessment of the right side of the heart is important in patients with heart disease; especially in patient with elevated pressure in the lung circulation. Decreased right ventricular function and elevated pressure in the right atrium are of poor prognostic value. Two-dimensional echocardiography (ultrasound of the heart) is the most commonly used method to assess the hearts function, but the right ventricle is hard to assess with this method. This is partly due to a 2-dimensional method has intrinsic problems to assess a 3-dimensional complex structure such as the right side of the heart. Magnetic resonance imaging of the heart and 3-dimensional (3D) echocardiography can be used for imaging in three dimensions.<br/><br>
The aim of this thesis is to assess how 3D echocardiography and magnetic resonance imaging of the heart can be used to determine the right heart function; and due to this determine how the heart pump physiology is altered by elevated right atrial and pulmonary pressure. In this thesis, echocardiography and magnetic resonance imaging is used with 2D and 3D technique.<br/><br>
Study I showed how to acquire 3D echocardiography for volume assessment of both atria and ventricles in adult cardiac patients. Acquisition from the apex of the heart, with at times an 'off-axis' approach, should be used for volumetric assessment with 3D echocardiography. While the atria and the left ventricle were well visualized, the right ventricle was a challenge.<br/><br>
Study II aimed to validated right ventricular volumes and function, in a population of adult cardiac patients, with 3D echocardiography using magnetic resonance imaging as a reference. The study showed the difficulty to asses right ventricular volumes and function, even when using 3D echocardiography in a clinically unselected population. Furthermore, the study showed the importance of manual corrections to achieve reasonably valid measurements, when compared to magnetic resonance imaging.<br/><br>
Study III assessed elevated right atrial pressure by quantifying right atrial volumes with 3D echocardiography in patients with elevated pressure in the lung circulation. The volumes were compared to invasively measured pressure values and magnetic resonance imaging. The study showed that 3D as well as 2D echocardiographic volume assessment of the right atrium were better than the conventional echocardiographic methods to determine elevated right atrial pressure. This was despite a substantial underestimation of the 3D echocardiographic volumes compared to magnetic resonance imaging. <br/><br>
Study IV examined the different contributions to right and left ventricular stroke volume in patients with elevated pressure in the lung circulation; and compared to those of healthy adults. Magnetic resonance imaging was used given the results of study II and pressure was quantified by right sided catheterization. The study showed that longitudinal and lateral contribution to left ventricular stroke volume was altered in patients with elevated pressure in the lung circulation compared to the control group. Right ventricular longitudinal and lateral contribution to stroke volume did not differ between patients and controls. The septum moved to the left in both groups, however less in patients than in healthy adults. In patients with elevated pressure in the lung circulation and hence pressure loaded right ventricles, the different components of pump function are altered in a different compared to volume loaded right ventricles. This is new information that helps understand the hearts physiology.},
  author       = {Ostenfeld, Ellen},
  isbn         = {978-91-87651-57-1},
  issn         = {1652-8220},
  keyword      = {Key words Three-dimensional echocardiography,cardiac magnetic resonance imaging,cardiac function,volumes,atria,ventricles,pulmonary hypertension,right heart catheterization,right ventricular pressure load.},
  language     = {eng},
  pages        = {142},
  publisher    = {Department of Clinical Physiology, Lund University},
  school       = {Lund University},
  series       = {Lund University, Faculty of Medicine Doctoral Dissertation Series},
  title        = {Three-dimensional assessment of cardiac function; When right is wrong},
  volume       = {2014:33},
  year         = {2014},
}