Dataset Information

Visualization of fibroblast activation using ⁶⁸Ga-FAPI PET/CT after pulmonary vein isolation with pulsed field compared with cryoballoon ablation.

ABSTRACT:

Background

Pulsed-field ablation (PFA) is a novel ablation modality for atrial fibrillation (AF) ablating myocardium by electroporation without tissue-heating. With its different mechanism of tissue ablation, it is assumed that lesion creation is divergent to thermal energy sources. ⁶⁸Ga-fibroblast-activation protein inhibitor (FAPI) PET/CT targets FAP-alpha expressed by activated fibroblasts. We aimed to assess ⁶⁸Ga-FAPI uptake in pulmonary veins as surrogate for ablation damage after PFA and cryoballoon ablation (CBA).

Methods

26 patients (15 PFA, 11 CBA) underwent ⁶⁸Ga-FAPI-PET/CT after ablation. Standardized uptake values (SUV) and fibroblast-activation volumes of localized tracer uptake were assessed.

Results

Patient characteristics were comparable between groups. In PFA, focal FAPI uptake was only observed in 3/15 (20%) patients, whereas in the CBA cohort, 10/11 (90.9%) patients showed atrial visual uptake. We observed lower values of SUV_max (2.85 ± 0.56 vs 4.71 ± 2.06, P = 0.025) and FAV (1.13 ± 0.84 cm³ vs 3.91 ± 2.74 cm³, P = 0.014) along with a trend towards lower SUV_peak and SUV_mean in PFA vs CBA patients, respectively.

Conclusion

Tissue response with respect to fibroblast activation seems to be less pronounced in PFA compared to established thermal ablation systems. This functional assessment might contribute to a better understanding of lesion formation in thermal and PFA ablation potentially contributing to better safety outcomes.

SUBMITTER: Kupusovic J

PROVIDER: S-EPMC10558367 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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Publications

Visualization of fibroblast activation using <sup>68</sup>Ga-FAPI PET/CT after pulmonary vein isolation with pulsed field compared with cryoballoon ablation.

Kupusovic Jana J Kessler Lukas L Bruns Florian F Bohnen Jan-Eric JE Nekolla Stephan G SG Weber Manuel M MM Lauenroth Anna A Rattka Manuel M Hermann Ken K Dobrev Dobromir D Rassaf Tienush T Wakili Reza R Rischpler Christoph C Siebermair Johannes J

Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology 20230321 5

<h4>Background</h4>Pulsed-field ablation (PFA) is a novel ablation modality for atrial fibrillation (AF) ablating myocardium by electroporation without tissue-heating. With its different mechanism of tissue ablation, it is assumed that lesion creation is divergent to thermal energy sources. <sup>68</sup>Ga-fibroblast-activation protein inhibitor (FAPI) PET/CT targets FAP-alpha expressed by activated fibroblasts. We aimed to assess <sup>68</sup>Ga-FAPI uptake in pulmonary veins as surrogate for a ...[more]

PMID: 36944827

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Project description:Heart failure remains a major source of late morbidity and mortality after myocardial infarction (MI). The temporospatial presence of activated fibroblasts in the injured myocardium predicts the quality of cardiac remodeling after MI. Therefore, monitoring of activated fibroblasts is of great interest for studying cardiac remodeling after MI. Fibroblast activation protein (FAP) expression is upregulated in activated fibroblasts. This study investigated the feasibility of imaging activated fibroblasts with a new 68Ga-labeled FAP inhibitor (68Ga-FAPI-04) for PET imaging of fibroblast activation in a preclinical model of MI. Methods: MI and sham-operated rats were scanned with 68Ga-FAPI-04 PET/CT (1, 3, 6, 14, 23, and 30 d after MI) and with 18F-FDG (3 d after MI). Dynamic 68Ga-FAPI-04 PET and blocking studies were performed on MI rats 7 d after coronary ligation. After in vivo scans, the animals were euthanized and their hearts harvested for ex vivo analyses. Cryosections were prepared for autoradiography, hematoxylin and eosin (H&E), and immunofluorescence staining. Results: 68Ga-FAPI-04 uptake in the injured myocardium peaked on day 6 after coronary ligation. The tracer accumulated intensely in the MI territory, as identified by decreased 18F-FDG uptake and confirmed by PET/MR and H&E staining. Autoradiography and H&E staining of cross-sections revealed that 68Ga-FAPI-04 accumulated mainly at the border zone of the infarcted myocardium. In contrast, there was only minimal uptake in the infarct of the blocked rats, comparable to the uptake in the remote noninfarcted myocardium (PET image-derived ratio of infarct uptake to remote uptake: 6 ± 2). Immunofluorescence staining confirmed the presence of FAP-positive myofibroblasts in the injured myocardium. Morphometric analysis of the whole-heart sections demonstrated 3- and 8-fold higher FAP-positive fibroblast density in the border zone than in the infarct center and remote area, respectively. Conclusion: 68Ga-FAPI-04 represents a promising radiotracer for in vivo imaging of post-MI fibroblast activation. Noninvasive imaging of activated fibroblasts may have significant diagnostic and prognostic value, which could aid clinical management of patients after MI.

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Dataset Information

Visualization of fibroblast activation using ⁶⁸Ga-FAPI PET/CT after pulmonary vein isolation with pulsed field compared with cryoballoon ablation.

Background

Methods

Results

Conclusion

Publications

Visualization of fibroblast activation using <sup>68</sup>Ga-FAPI PET/CT after pulmonary vein isolation with pulsed field compared with cryoballoon ablation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Visualization of fibroblast activation using 68Ga-FAPI PET/CT after pulmonary vein isolation with pulsed field compared with cryoballoon ablation.

Background

Methods

Results

Conclusion

Publications

Visualization of fibroblast activation using <sup>68</sup>Ga-FAPI PET/CT after pulmonary vein isolation with pulsed field compared with cryoballoon ablation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Visualization of fibroblast activation using ⁶⁸Ga-FAPI PET/CT after pulmonary vein isolation with pulsed field compared with cryoballoon ablation.