{"id":14713,"date":"2026-03-31T07:18:47","date_gmt":"2026-03-31T05:18:47","guid":{"rendered":"https:\/\/www.proefschriftmaken.nl\/us_portfolio\/a-zweerink-2-3\/"},"modified":"2026-08-14T17:47:06","modified_gmt":"2026-08-14T15:47:06","slug":"a-zweerink-2-3","status":"publish","type":"us_portfolio","link":"https:\/\/www.proefschriftmaken.nl\/en\/portfolio\/a-zweerink-2-3\/","title":{"rendered":"a.zweerink"},"content":{"rendered":"","protected":false},"featured_media":10619,"template":"","meta":{"_acf_changed":false},"university_us_portfolio":[28],"class_list":["post-14713","us_portfolio","type-us_portfolio","status-publish","has-post-thumbnail","hentry","university_us_portfolio-vrije-universiteit-amsterdam"],"acf":{"main_text":"","naam_van_het_proefschift":"Tailored Cardiac Resynchronization Therapy","samenvatting":"Hartfalen is een klinisch syndroom dat gekenmerkt wordt door een afwijking van de cardiale structuur of functie die leidt tot het falen van het hart om de benodigde zuurstof te leveren aan de weefsels en organen. In praktijk zal dit zich uiten door snelle vermoeidheid en kortademigheid bij geringe inspanning. Een kwart van de pati\u00ebnten die zich presenteren met hartfalen heeft een geleidingsstoornis in het hart met een verlengde QRS-duur op het elektrocardiogram (ECG), meestal een linkerbundeltakblok (LBTB). Cardiale Resynchronisatietherapie (CRT) heeft een bewezen gunstig effect op de kwaliteit van leven en overleving van pati\u00ebnten met hartfalen en een LBTB. Bij een-derde van de pati\u00ebnten treedt echter geen verbetering op, de zogenaamde \u201cnon-responders\u201d.\n\nDeel IA richt zich op het normaliseren van de QRS-duur ten opzichte van de grootte van het hart. Hoewel een toename in QRS-duur het gevolg kan zijn van trage cel-tot-cel geleiding, kan deze ook het gevolg zijn van een toename in geleidingsafstand door dilatatie van het falende hart. Het normaliseren van de QRS-duur voor de hartgrootte verbeterde de relatie met acute pompfunctie veranderingen en de overlevingsduur na CRT implantatie. Ook verklaart dit mogelijk waarom vrouwen vaak beter reageren op CRT; omdat hun harten kleiner zijn, betekent een vergelijkbare QRS-duur bij hen meer relatieve geleidingsvertraging.\n\nDeel IB onderzoekt de rol van beeldvormende technieken die de myocardiale contractie visualiseren. Een lage arbeidsbijdrage (hoge arbeidsverspilling) van het septum bleek gerelateerd aan een grotere pompfunctieverbetering tijdens CRT. De eind-systolische septum lengteverandering (ESSsep) bleek de sterkste voorspeller voor succes, onafhankelijk van de gebruikte techniek (MRI of echo). Er werd een nieuwe techniek ge\u00efntroduceerd, de segment lengte in cine (SLICE) analyse, waarmee deze waarden simpel handmatig bepaald kunnen worden op standaard MRI beelden.\n\nIn deel II worden strategie\u00ebn beschreven om CRT instellingen na implantatie te optimaliseren. Hoewel er grote variatie was in de respons tussen verschillende electroden van de quadripolaire linkerventrikel draad, bleken elektrische parameters niet in staat de beste electrode te identificeren. Hemodynamische optimalisatie resulteerde in een verbetering van een-derde in slagarbeid (SW) of contractiliteit (dP\/dtmax). Alleen acute veranderingen in slagarbeid bleken echter de respons op lange termijn te kunnen voorspellen. Tot slot wordt een overzicht gegeven van de behandeling van chronotrope incompetentie (het onvermogen om de hartslag voldoende te verhogen tijdens inspanning) bij hartfalenpati\u00ebnten middels frequentie-adaptieve pacemakertherapie.","summary":"Selection criteria for Cardiac Resynchronization Therapy (CRT) are mainly based on the morphology and time duration of the QRS complex. Following guideline criteria, however, approximately one-third of the patients implanted with CRT will not respond favorably. Over the last two decades, numerous studies have sought to determine variables associated with improved CRT response. It is now widely accepted that these factors include strict left bundle branch block (LBBB) morphology, longer QRS duration (QRSd), sinus rhythm, non-ischemic etiology, younger age and female gender. On the other hand, consensus has still not been reached on the predictive value of cardiac imaging techniques in CRT candidates. On this matter, the role of myocardial strain parameters is especially debated. After the decision to implant CRT has been made, the question arises if device optimization strategies increases benefit from the therapy. This, again, is topic of significant debate and requires further research. The present thesis aims to investigate two strategies that can potentially increase effectiveness of CRT: (i) improved selection of potential responders prior to implantation using cardiac imaging techniques and (ii) optimized device settings afterwards in order to maximize hemodynamic benefits.\n\nPart IA evaluates the theoretical concept that incorporation of left ventricular (LV) structural measurements in the assessment of electrical delay, by normalizing QRSd to LV size, improves prediction of CRT response. Normalization of QRSd to LV dimension (i.e. QRSd divided by LV dimension) improved correlation with acute LV pump function improvement by CRT. Different metrics of LV size (volumes; diameter; length; mass) all showed similar results in relation to QRSd and CRT response. In addition, women achieved more pump function improvement during CRT compared to men. This sex-specific difference in CRT outcome may be partly ascribed to differences in LV size between both sexes. As the female heart is generally smaller, women have shorter QRSd compared to men. In order to reach the cut-off QRSd value for CRT (guidelines are identical for men and women), female hearts will have more conduction delay compared to male hearts and might therefore be more amenable for successful treatment with CRT. QRSd normalization improved prediction of survival after CRT implantation.\n\nPart IB of this thesis evaluates the role of myocardial strain imaging to improve patient selection for CRT. Contribution of the septum to total LV work varies widely in CRT candidates with LBBB, and the lower the septal contribution to total myocardial work (or the higher the septal waste) at baseline the higher the acute improvement in pump function that can be achieved during CRT. Myocardial strain imaging therefore provides an insight in the negative effect of LBBB on myocardial work and energy utilization, and reflects the potential benefit that can be achieved by CRT. Of all strain parameters, measuring end-systolic septal strain (ESSsep) showed strongest relation with CRT response after one year, irrespective of imaging technique. Detection of septal discoordination with higher ESSsep values (i.e. septal stretching instead of contraction) at baseline was associated with more extensive reverse remodeling after CRT. The novel segment length in cine (SLICE) strain technique provides a simplified strain analysis technique to estimate benefit from CRT by analyzing standard CMR cine images.\n\nIn part two of this thesis several CRT optimization strategies are evaluated. Although there was a large variation in acute hemodynamic CRT response between different electrodes of the quadripolar lead, electrical parameters (QLV; QLV\/QRSd) were unable to identify the most beneficial pacing electrode. Optimization of the pacing configuration should rely on functional assessment of cardiac function, instead of local electrical delay. It was demonstrated that hemodynamic optimization of the LV pacing electrode and AV delay in CRT with quadripolar leads result in approximately one-third additional improvement in the parameter used for optimization (either dP\/dtmax or SW). Whereas dP\/dtmax optimization favored LV contractility, SW optimization improved ventricular-arterial coupling leading to higher stroke volume and ejection. Acute changes in SW showed high predictive value for prediction of long-term CRT response.","auteur":"a.zweerink","auteur_slug":"azweerink","publicatiedatum":"24 april 2020","taal":"EN","url_flipbook":"https:\/\/ebook.proefschriftmaken.nl\/ebook\/azweerink?iframe=true","url_download_pdf":"https:\/\/ebook.proefschriftmaken.nl\/download\/b91019b5-28c3-4f16-9364-29dd150b0313\/optimized","url_epub":"","ordernummer":"FTP-202603310712","isbn":"978-94-6380-761-6","doi_nummer":"","naam_universiteit":"Vrije Universiteit Amsterdam","afbeeldingen":10619,"video_url":"","podcast_url":"","naam_student:":"","binnenwerk":"","universiteit":"Vrije Universiteit Amsterdam","cover":"","afwerking":"","cover_afwerking":"","design":""},"_links":{"self":[{"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/us_portfolio\/14713","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/us_portfolio"}],"about":[{"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/types\/us_portfolio"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/media\/10619"}],"wp:attachment":[{"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/media?parent=14713"}],"wp:term":[{"taxonomy":"university_us_portfolio","embeddable":true,"href":"https:\/\/www.proefschriftmaken.nl\/en\/wp-json\/wp\/v2\/university_us_portfolio?post=14713"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}