liu.seSearch for publications in DiVA
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
The right ventricle in volume or pressure overload: Insights from novel imaging techniques
Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
2019 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

This study is inspired by the gap in knowledge regarding the timing of cardiac surgery and interventions in adult patients with congenital heart disease. There are many parameters used assessing right ventricular function; however, most of them have pitfalls. Understanding the pathomechanisms by which the heart adapts to congenital defects is probably key to find the answer when it is time to intervene and start discussing treatment options. Heart defects are the most frequently occurring congenital disorders. Less than 50% of individuals with moderate to severe congenital heart defects, e.g. transposition of the great arteries (TGA) or tetralogy of Fallot (TOF), survive to adulthood without intervention. Advances in cardiac surgery and better identification of individuals at risk for sudden cardiac death have increased survival rates. Currently, more than 96% of patients with congenital heart disease survive to at least 16 years of age; most undergo corrective surgery but are not cured, and only a few have normal physiology and anatomy. In many cases, the heart must develop mechanisms of adaptation to the changed conditions after surgery. Consequently, correction of the defect creates residual disease with a risk of future complications.

To prevent clinical deterioration and to identify the development of complications, patients need lifelong, regular follow up. The choice of followup modalities depends on the cardiac malformation.

The right ventricle (RV) plays an important role, as it is often part of the defect or is influenced by the surgery. In the past, research was focused on assessment of left ventricular function (LV), and the RV was “the forgotten ventricle.” Observations and studies in the last few decades brought increased interest into the RV and revealed the importance of the RV in the prognosis of various cardiac diseases.

An understanding of RV morphology, pathophysiology and adaptive mechanisms is crucial for further studies of prognosis as well as for research linked to the use of particular diagnostic modalities.

When the RV is exposed to increased pressure load, e.g. in atrially corrected transposition of the great arteries (TGA), adaptation affects the cavity volume as well as the wall thickness. When the RV is volume overloaded, adaptation involves enhancement of the RV cavity volume while the wall thickness often remains unchanged under long time. RV ejection fraction (RVEF) gives some information about changes in RV function, but information on myocardial contractility and contractile reserve is also needed. New functional parameters such as strain—also known as myocardial deformation—provide some information about intrinsic myocardial function.

In Paper I, we studied functional parameters such as ejection fraction and strain (radial and longitudinal strain for both ventricles) in patients with Tetralogy of Fallot (TOF) and TGA. Longitudinal RV strain was depressed in both patient groups in comparison with that in healthy individuals, and there were additional differences between the two patient groups.

In Paper II, we validated three-dimensional echocardiography (3DEcho) against the cardiac magnetic resonance (CMR) gold standard. The study population was limited to patients with TOF. In general, 3DEcho underestimated RV volumes but was able to identify patients with RV dilatation on CMR with high sensitivity. RV longitudinal free wall strain measured by CMR with a cut-off set at -14% identified patients with depressed exercise capacity and low peak oxygen uptake.

In Paper III, we studied a new CMR method to quantify and visualise turbulent flow in the heart and vessels. Turbulent flow can be harmful to tissue, blood cells, and endothelium and can contribute to tissue remodeling. In patients with TOF, turbulent flow can be seen as variance in 2DEcho color Doppler. In CMR, increased turbulent kinetic energy (TKE) could be seen with four-dimensional flow. The RV TKE was increased in patients with TOF with pulmonary regurgitation compared with that in healthy controls.

In Paper IV, we validated “knowledge-based reconstruction” (KBR), a novel method to calculate RV volume, against CMR in patients with various types of congenital heart defects. Two-dimensional echocardiogram-based threedimensional RV reconstruction is a relatively uncomplicated method that creates a three-dimensional RV model based on a limited number of predefined points of interest (RV structures such as tricuspid annulus, RV free wall, or pulmonary valve).

KBR showed good agreement with CMR (intraclass correlation coefficient = 0.84 for RV end-diastolic volume and 0.89 for ejection fraction) but tended to underestimate RV volumes, which is in line with other methods based on ultrasound.

Conclusions: 3DEcho is an evolving modality that is able to identify patients with RV dilatation. It can be used clinically for the follow up of patients with congenital heart diseases, especially those with mildly to moderately dilated RVs. When an intervention seems likely, 3DEcho results should be verified by CMR. CMR-derived measurements of longitudinal and radial strain provide a new understanding of RV remodeling and ventricular interdependence in patients with TOF and TGA. Depressed longitudinal strain may indicate a risk of depressed exercise capacity and, in patients with TGA, clinical deterioration.

Further studies in larger populations of patients with congenital heart defects are needed, as the altered RV morphology in such patients makes quantitative assessment especially challenging.

Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 2019. , p. 82
Series
Linköping University Medical Dissertations, ISSN 0345-0082 ; 1653
National Category
Cardiac and Cardiovascular Systems
Identifiers
URN: urn:nbn:se:liu:diva-153732DOI: 10.3384/diss.diva-153732ISBN: 9789176851678 (print)OAI: oai:DiVA.org:liu-153732DiVA, id: diva2:1275929
Public defence
2019-02-15, Hugo Theorell-salen, Campus US, Linköping, 13:00 (English)
Opponent
Supervisors
Note

Korrigeringar är gjorda i den elektroniska versionen utifrån publicerad erratalista / The corrections in the published errata list are implemented in the electronic version.

Available from: 2019-01-07 Created: 2019-01-07 Last updated: 2019-02-11Bibliographically approved
List of papers
1. Afterload dependence of right ventricular myocardial deformation: A comparison between tetralogy of Fallot and atrially corrected transposition of the great arteries in adult patients
Open this publication in new window or tab >>Afterload dependence of right ventricular myocardial deformation: A comparison between tetralogy of Fallot and atrially corrected transposition of the great arteries in adult patients
Show others...
2018 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 13, no 9, article id e0204435Article in journal (Refereed) Published
Abstract [en]

Background

Prior studies suggested that myocardial deformation is superior to conventional measures for assessing ventricular function. This study aimed to evaluate right ventricular (RV) myocardial deformation in response to increased afterload. Patients with the RV in the systemic position were compared with patients with the RV in the sub-pulmonic position with normal or only slightly elevated systolic right ventricular pressure. Correlations between global longitudinal strain (GLS), radial strain, atrioventricular plane displacement (AVPD), and exercise capacity were evaluated.

Methods

44 patients with congenital heart defect were enrolled in the study. The control group consisted of seven healthy volunteers. All patients underwent cardiovascular magnetic resonance (CMR) and cardiopulmonary exercise testing. We assessed biventricular myocardial function using CMR based feature tracking and compared the results to anatomic volumes.

Results

Strain analysis and displacement measurements were feasible in all participants. RVGLS and RVAVPD were reduced in both study groups compared to the control group (p<0.001). Left ventricular (LV) radial strain was significantly lower in patients with a systemic RV than in those with a subpulmonic RV and lower than in controls (p<0.001). Both LVAVPD and RVAVPD were significantly depressed in patients compared to controls (p<0.05). RVAVPD was more depressed in patients with a high systolic RV pressure than in those with normal RV pressure (p<0.001). RVAVPD did not correlate with exercise capacity in either study group. Exercise capacity in both patient groups was depressed to levels reported in previous studies, and did not correlate with RVGLS.

Conclusions

Both study groups had abnormal myocardial deformation and increased RV volumes. RVGLS in patients was lower than in controls, confirming the effect of increased afterload on myocardial performance.

Place, publisher, year, edition, pages
San Francisco, CA, United States: Public Library of Science, 2018
National Category
Cardiac and Cardiovascular Systems
Identifiers
urn:nbn:se:liu:diva-152085 (URN)10.1371/journal.pone.0204435 (DOI)000445907400049 ()30261015 (PubMedID)2-s2.0-85054059580 (Scopus ID)
Note

Funding Agencies|ALF Grant, Region Ostergotland [LIO-281281]

Available from: 2018-10-17 Created: 2018-10-17 Last updated: 2019-01-07Bibliographically approved
2. Turbulent kinetic energy in the right ventricle: Potential MR marker for risk stratification of adults with repaired Tetralogy of Fallot
Open this publication in new window or tab >>Turbulent kinetic energy in the right ventricle: Potential MR marker for risk stratification of adults with repaired Tetralogy of Fallot
Show others...
2018 (English)In: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 47, no 4, p. 1043-1053Article in journal (Refereed) Published
Abstract [en]

Purpose: To assess right ventricular (RV) turbulent kinetic energy (TKE) in patients with repaired Tetralogy of Fallot (rToF) and a spectrum of pulmonary regurgitation (PR), as well as to investigate the relationship between these 4D flow markers and RV remodeling.

Materials and Methods: Seventeen patients with rToF and 10 healthy controls were included in the study. Patients were divided into two groups based on PR fraction: one lower PR fraction group (11%) and one higher PR fraction group (>11%). Field strength/sequences: 3D cine phase contrast (4D flow), 2D cine phase contrast (2D flow), and balanced steady-state free precession (bSSFP) at 1.5T. Assessment: The RV volume was segmented in the morphologic short-axis images and TKE parameters were computed inside the segmented RV volume throughout diastole. Statistical tests: One-way analysis of variance with Bonferroni post-hoc test; unpaired t-test; Pearson correlation coefficients; simple and stepwise multiple regression models; intraclass correlation coefficient (ICC).

Results: The higher PR fraction group had more remodeled RVs (140 6 25 vs. 107 6 22 [lower PR fraction, P < 0.01] and 93 6 15 ml/m2[healthy, P < 0.001] for RV end-diastolic volume index [RVEDVI]) and higher TKE values (5.95 6 3.15 vs. 2.23 6 0.81 [lower PR fraction, P < 0.01] and 1.91 6 0.78 mJ [healthy, P < 0.001] for Peak Total RV TKE). Multiple regression analysis between RVEDVI and 4D/2D flow parameters showed that Peak Total RV TKE was the strongest predictor of RVEDVI (R25 0.47, P 5 0.002).

Conclusion: The 4D flow-specific TKE markers showed a slightly stronger association with RV remodeling than conventional 2D flow PR parameters. These results suggest novel hemodynamic aspects of PR in the development of late complications after ToF repair.

Place, publisher, year, edition, pages
Hoboken: John Wiley & Sons, 2018
Keywords
4D flow, MRI, Turbulence, Tetralogy of Fallot, Turbulent kinetic energy
National Category
Radiology, Nuclear Medicine and Medical Imaging Cardiac and Cardiovascular Systems Medical Laboratory and Measurements Technologies Anesthesiology and Intensive Care Medical Image Processing
Identifiers
urn:nbn:se:liu:diva-143780 (URN)10.1002/jmri.25830 (DOI)000427125300016 ()28766919 (PubMedID)2-s2.0-85026745981 (Scopus ID)
Note

Funding agencies:  European Research Council [310612]; Swedish Heart and Lung Foundation [20140398]; County Council of Ostergotland; Medical Research Council of Southeast Sweden (FORSS); Swedish Research Council [2013-6077, 2014-6191]

Available from: 2017-12-18 Created: 2017-12-18 Last updated: 2019-01-07Bibliographically approved
3. Knowledge-based 3D reconstruction of the right ventricle: comparison with cardiac magnetic resonance in adults with congenital heart disease
Open this publication in new window or tab >>Knowledge-based 3D reconstruction of the right ventricle: comparison with cardiac magnetic resonance in adults with congenital heart disease
Show others...
2015 (English)In: Echo research and practice, ISSN 2055-0464, Vol. 2, no 4, p. 109-116Article in journal (Refereed) Published
Abstract [en]

AIM: Assessment of right ventricular (RV) function is a challenge, especially in patients with congenital heart disease (CHD). The aim of the present study is to assess whether knowledge-based RV reconstruction, used in the everyday practice of an echo-lab for adult CHD in a tertiary referral center, is accurate when compared to cardiac magnetic resonance (CMR) examination.

SUBJECTS AND METHODS: Adult patients who would undergo CMR for assessment of the RV were asked to undergo an echo of the heart for further knowledge-based reconstruction (KBR). Echocardiographic images were acquired in standard views using a predefined imaging protocol. RV volumes and ejection fraction (EF) calculated using knowledge-based technology were compared with the CMR data of the same patient.

RESULTS: Nineteen consecutive patients with congenital right heart disease were studied. Median age of the patients was 28 years (range 46 years). Reconstruction was possible in 16 out of 19 patients (85%). RV volumes assessed with this new method were smaller than with CMR. Indexed end diastolic volumes were 114±17 ml vs 121±19 ml, P<0.05 and EFs were 45±8% vs 47±9%, P<0.05 respectively. The correlation between the methods was good with an intraclass correlation of 0.84 for EDV and 0.89 for EF, P value <0.001 in both cases.

CONCLUSION: KBR enables reliable measurement of RVs in patients with CHDs and can be used in clinical practice for analysis of volumes and EFs.

Keywords
congenital heart disease; knowledge-based reconstruction; right ventricle volume; ventripoint system
National Category
Cardiac and Cardiovascular Systems
Identifiers
urn:nbn:se:liu:diva-124289 (URN)10.1530/ERP-15-0029 (DOI)26796613 (PubMedID)
Available from: 2016-01-25 Created: 2016-01-25 Last updated: 2019-01-07

Open Access in DiVA

The right ventricle in volume or pressure overload: Insights from novel imaging techniques(2138 kB)23 downloads
File information
File name FULLTEXT04.pdfFile size 2138 kBChecksum SHA-512
9c691f58df347eb660eb455004ec92c209dc56dfbacb5092fab485357174aadbac72b7772e465e4fa61c7dc4f1b850091e27fdbcc7419917295a1a2258a89d9a
Type fulltextMimetype application/pdf
errata(57 kB)1 downloads
File information
File name ERRATA03.pdfFile size 57 kBChecksum SHA-512
5b34193472ac926b1396f6158a32d19517d09640e0169b3b9c5834200432c8b3387d3e083da7e5166b7aa674ca237f1559563693ca51ee05c5418eda64ceaa4f
Type errataMimetype application/pdf

Other links

Publisher's full text

Authority records BETA

Trzebiatowska-Krzynska, Aleksandra

Search in DiVA

By author/editor
Trzebiatowska-Krzynska, Aleksandra
By organisation
Division of Cardiovascular MedicineFaculty of Medicine and Health Sciences
Cardiac and Cardiovascular Systems

Search outside of DiVA

GoogleGoogle Scholar
Total: 54 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

doi
isbn
urn-nbn

Altmetric score

doi
isbn
urn-nbn
Total: 258 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf