Umeå University's logo

umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • 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
Reversed Apico-Basal Myocardial Relaxation Sequence During Exercise in Long QT Syndrome Mutations Carriers With History of Previous Cardiac Events
Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Medicine. Division of Pediatric Cardiology, Department of Pediatrics, Amalia Children’s Hospital, Radboud University Medical Center, Nijmegen, Netherlands; Academic Centre for Congenital Heart Disease, Nijmegen, Netherlands.ORCID iD: 0000-0001-6566-7867
Department of Biochemical Sciences, Pomeranian Medical University, Szczecin, Poland.
Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.ORCID iD: 0000-0001-9655-7783
Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Section of Medicine.ORCID iD: 0000-0002-6089-5614
2022 (English)In: Frontiers in Physiology, E-ISSN 1664-042X, Vol. 12, article id 780448Article in journal (Refereed) Published
Abstract [en]

Background: Recent echocardiography studies in inherited long QT syndrome (LQTS) have shown left ventricular (LV) myocardial relaxation disturbances to follow markedly prolonged and dispersed mechanical contraction. Aim: We used speckle-tracking echocardiography to assess disturbances in LV myocardial relaxation sequence during exercise and their relationship to symptoms. Methods: Forty seven LQTS patients (45 ± 15 years, 25 female and 20 symptomatic, LVEF: 65 ± 6%) and 35 controls underwent exercise echocardiogram using Bruce protocol. ECG and echo parameters were recorded at rest, peak exercise (p.e.) and recovery. Results: Between patients and controls there were no differences in age, gender, HR or LVEF. At p.e, patients had longer time to LV longitudinal ESR (tESR) at all three LV segments; basal (p < 0.0001), mid- cavity (p = 0.03) and apical (p = 0.03) whereas at rest such difference was noted only at base (p = 0.0007). Patients showed reversed apico-basal relaxation sequence (ΔtESRbase–apex) with early relaxation onset occurring later at base than at apex, both at rest (49 ± 43 vs. –29 ± 19 ms, p < 0.0001) and at p.e. (46 ± 38 vs. –40 ± 22 ms, p < 0.0001), particularly in symptomatic patients (69 ± 44 vs. 32 ± 26, p < 0.0007). ΔtESRbase–apex correlated with longer QTc interval, lower ESR and attenuated LV stroke volume. Conclusion: LQTS patients show reversed longitudinal relaxation sequence, which worsens with exercise, particularly in those with previous cardiac events.

Place, publisher, year, edition, pages
Frontiers Media S.A., 2022. Vol. 12, article id 780448
Keywords [en]
arrhythmia, diastolic function, exercise stress echocardiogram, long QT syndrome, myocardial relaxation sequence, speckle-tracking echocardiography
National Category
Cardiac and Cardiovascular Systems
Identifiers
URN: urn:nbn:se:umu:diva-192781DOI: 10.3389/fphys.2021.780448ISI: 000760694500001PubMedID: 35197859Scopus ID: 2-s2.0-85124992601OAI: oai:DiVA.org:umu-192781DiVA, id: diva2:1643167
Available from: 2022-03-09 Created: 2022-03-09 Last updated: 2024-01-17Bibliographically approved
In thesis
1. Myocardial electromechanical function in long QT syndrome
Open this publication in new window or tab >>Myocardial electromechanical function in long QT syndrome
2022 (English)Doctoral thesis, comprehensive summary (Other academic)
Alternative title[sv]
Myokardiell elektromekanisk function i långt QT-syndrom
Abstract [en]

AIM: The aim of this thesis is to assess, in LQTS and according to genotype, the myocardial electromechanical (EM) function response to exercise, its relation to symptoms and its response to b-blocker therapy. To achieve this aim, we conducted 4 studies with the following specific objectives: 

i. To study the ventricular repolarization (QTc interval) behaviour during stress and its potential haemodynamic effects, as reflected in left ventricular filling and stroke volume response to exercise.

ii. To access the exercise response of electromechanical coupling, expressed by the electromechnical window (EMW), and its relation to symptoms.

iii. To access for potential mechanical disturbances during stress by studying the myocardial contraction response to exercise, its effects on myocardial diastolic function and their relation to co-existent ventricular repolarization disturbances.

iv. To investigate the myocardial behaviour during early relaxation an most particularly the longitudinal apico-basal relaxation sequence, its synamic response to exercise and any potentia contribution to the development of symptoms.

v. To investigate the effect of b-blocker therapy on the above electromechanical parameters at rest and during exercise. 

METHODS: Forty seven (age 45±15yrs, 25 female, 20 symptomatic) LQTS mutation carriers and 35 healthy individuals (matched for age and sex) underwent an exercise test (Bruce protocol). ECG and doppler and speckle-tracking echo parameters were recorded at rest, peak exercise and recovery. 

RESULTS: We found that abnormal ventricular repolarization in LQTS carriers was related to marked LV mechanical dispersion and to abnormally reversed LV end-systolic electromechanical relationship and longitudinal early relaxation sequence. These phenomena worsened at peak exercise, especially in LQT1 carriers, and were related to impaired LV daistolic function and attenuated stroke volume response to exercise. Such abnormal electromechanical responses to exercise were more pronounces in LQTS subjects with previous adverse cardiac events and could better identigy these subjects than QTc interval alone. These disturbances were also less pronounced in LQTS carriers treated with b-blockers. 

CONCLUSION: Incorporating stress-echocardiograhic evaluation of electromechanical parameters in the routine assessment of LQTS individuals may help better stratification, symptom interpretation and management. 

Place, publisher, year, edition, pages
Umeå University, 2022. p. 161
Series
Umeå University medical dissertations, ISSN 0346-6612 ; 2210
Keywords
Long QT syndrome, stress-echocardiography, left ventricular filling, mechanical dispersion, diastolic myocardial function, exercise, arrhythmia, electromechanical window, speckle-tracking echocardiography, myocardial relaxation sequence.
National Category
Cardiac and Cardiovascular Systems
Research subject
Cardiology; cardiovascular disease
Identifiers
urn:nbn:se:umu:diva-200917 (URN)9789178559220 (ISBN)9789178559237 (ISBN)
Public defence
2022-12-01, Building 6E, R-1. Auditorium E04, Norrland University Hospital, Umeå, 09:00 (English)
Opponent
Supervisors
Available from: 2022-11-10 Created: 2022-11-09 Last updated: 2022-11-09Bibliographically approved

Open Access in DiVA

fulltext(1267 kB)130 downloads
File information
File name FULLTEXT01.pdfFile size 1267 kBChecksum SHA-512
2f7546ad22468cf14e2fb61bee7888c1104b127158f7d4840b1cb3a2a8a02c36b2b656b6b8e91d6fd795ee16614c43bc525a19b9cb2708a3b56652949edc87db
Type fulltextMimetype application/pdf

Other links

Publisher's full textPubMedScopus

Authority records

Charisopoulou, DafniRydberg, AnnikaHenein, Michael Y.

Search in DiVA

By author/editor
Charisopoulou, DafniRydberg, AnnikaHenein, Michael Y.
By organisation
Section of MedicinePaediatrics
In the same journal
Frontiers in Physiology
Cardiac and Cardiovascular Systems

Search outside of DiVA

GoogleGoogle Scholar
Total: 130 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
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 246 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • 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