Relationship between MRI First pass Perfusion Parameters and Biventricular Performance in Pulmonary Hypertension
Notice bibliographique
Résumé
The amount of blood flow through the lungs is determined by pulmonary by pressure gradient as well as cardiac function in PH. Dynamic contrast-enhanced MRI (DCE-MRI) enables high temporal resolution imaging to track the first transit of contrast material bolus through the pulmonary circulation. First-pass parameters such as pulmonary transit time (PTT), left ventricular (LV) full width at half maximum (FWHM), and LV time to peak (TTP) have been shown to be impaired in PAH compared to controls. Little has been reported regarding the relationship between first pass perfusion parameters in other groups of PH. Our aim was to explore the relationship between first-pass parameters and RV and LV performance in patients with group I (PAH) and group IV (chronic thromboembolic pulmonary hypertension) PH We prospectively recruited 9 patients with PH (pulmonary arterial hypertension, n=5; chronic thromboembolic pulmonary hypertension, n=4) who underwent CMR at 3T. CMR studies included functional (bSSFP) cine imaging for assessment of ventricular function, as well as phase contrast velocity encoded cine imaging obtained perpendicular to the main pulmonary artery (MPA) for assessment of MPA distensibility (%). To assess PTT, FWHM, and TTP, a 1:10 diluted bolus (0.0025 mmol/kg) of Gadobutrol was injected intravenously at 5 mL/s and followed using a single-shot saturation-recovery gradient-echo sequence in the short axis orientation (at the basal third of both ventricles). First-pass bolus kinetic parameters were determined by sampling the signal intensities in the RV and LV cavities and generating time-intensity curves for each ventricle. PTT was defined as the transit time of blood between the RV and LV, while FWHM and TTP were derived from the shape of the bolus in the LV cavity (Figure). Differences in first-pass parameters between the two groups were assessed using Mann-Whitney U tests and the relationship between each first-pass and functional parameters were investigated using Spearman's rank correlation (rho). There were no significant differences in first-pass parameters between groups (P>0.05 for each comparison). Significant negative correlations were found between FWHM and LV ejection fraction (rho=-0.72, p = 0.03) and LV cardiac output (rho=-0.68, p = 0.04) and FWHM was positively correlated with MPA distensibility (rho=0.73, p = 0.02). Trends towards negative correlations between PTT and RV (rho=-0.65, p = 0.06) and LV stroke volume indexed (rho=-0.60, p = 0.09) were also revealed. First pass perfusion parameters are similar in Group I and IV patients with PH. An increase in MPA distensibility is associated with an increase in FWHM. This may be attributed to advanced disease when RV cardiac output is decreased resulting in a paradoxical decrease in pulmonary pressures. Increased first-pass bolus dispersion (FWHM) may be a noninvasive marker of impaired pulmonary hemodynamics and biventricular dysfunction in groups I and IV patients with PH. Time intensity curves show transit of the contrast material bolus through the regions of interest in the right (blue) and left (red) ventricular cavities and indicate the first pass bolus parameters peak to peak PTT, FWHM and TTP .
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,001 | 0,003 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,001 | 0,001 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,001 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».