Aspetti Ultrasonografici in Corso di Sviluppo Placentare e Adattamento Cardiovascolare nella Cavalla Gravida: ecografia bidimensionale, ecocardiografia ed ecocontrastografia (CEUS)

In corso di gravidanza normale avvengono modificazioni emodinamiche centrali e periferiche volte a garantire le crescenti richieste nutritive dell'unità feto-placentare. L’ecografia con mezzo di contrasto (CEUS-Contrast Enhanced Ultrasonography) a base di microbolle offre una nuova opportunità di monitorare e quantificare la perfusione utero-placentare in condizioni normali e patologiche. L’ecocardiografia è stata ampiamente usata in medicina umana per valutare l’adattamento morfo-funzionale cardiaco materno durante la gravidanza. Gli scopi di questo lavoro prospettico sono stati di applicare, per la prima volta nella specie equina, un mezzo di contrasto di II generazione (Sonovue®), al fine quantificare la perfusione utero-placentare in corso di gravidanza normale, valutandone gli effetti sul benessere materno-fetale e di descrivere le modificazioni nei parametri ecocardiografici morfometrici e funzionali cardiaci, in particolare relativi alla funzione del ventricolo sinistro nel corso di una gravidanza fisiologica. Due fattrici sane di razza Trottatore sono state monitorate ecograficamente in maniera seriale durante l’intero corso della gravidanza, tramite esame bidimensionale, ecocontrastografia dell'unità utero-placentare, flussimetria Doppler delle arterie uterine, ecocardiografia materna in modalità bidimensionale, M-mode, Doppler e Tissue Doppler Imaging. I neonati sono stati clinicamente monitorati e gli invogli fetali esaminati. Il pattern di microperfusione utero-placentare è valutabile quali-quantitativamente tramite la CEUS e dimostra un’aumento del flusso a livello di microvascolarizzazione uterina con l'avanzare della gravidanza; non è stata rilevata la presenza di microbolle a livello di strutture fetali nè effetti dannosi sul benessere materno-fetale. In questo studio sono state osservate delle modificazioni cardiache materne in corso di gravidanza fisiologica, relative all'aumento della FC, del CO ed in particolare all'aumento delle dimensioni dell'atrio sinistro ed a modificazioni nelle onde di velocità di flusso e tissutali di riempimento del ventricolo sinistro.

Development and validation of an echocardiography score for diagnosis of cardiac masses

Background Echocardiography is the cornerstone in the evaluation of cardiac masses and provides accurate characterization. Despite, its accuracy in diagnosis of cardiac masses (CM) remains challenging and, up to date, no validated diagnostic algorithm is validated. Purpose The aim of our study was to evaluate the diagnostic accuracy of echocardiography, to identify the echocardiographic predictors of malignancy and to develop and then validate a multiparametric echocardiographic score that could be used to estimate the likelihood of the histological nature of a CM. Materials and methods The final sample consisted of 273 consecutive patients who had a 2D-echocardiographic evaluation and a histologic diagnosis. Logistic regression was performed to evaluate the ability of echocardiographic findings to discriminate benign versus malignant masses, then a scoring system was developed and validated in a separate test cohort. Results Of the 322 patients initially included in the Bologna Cardiac Masses Registry, 13 with a poor acoustic window, 27 with no histological examination patients and 9 extra-cardiac masses were excluded. In the remaining 273 patients, classical 2-D echocardiogram identified 249 masses with a diagnostic accuracy of 88%. A weighted score [Diagnostic Echocardiographic Mass (DEM) Score] ranging from 0 to 9 was obtained from 6 variables: infiltration, polylobate mass, moderate-severe pericardial effusion. The AUC for the score was 0.965 (95% CI [0.938-0.993]). In a logistic regression analysis using the DEM score as a predictor, the likelihood of malignant CM increased more than 4 times for a 1-unit increase in the score (OR=4.468; 95% CI 2.733-7.304). A score < 3 denoted a high probability of a benign diagnosis, and a score ≥ 5 points corresponded to a higher risk of malignancy. Conclusion 2D-Echocardiography provides a high diagnostic accuracy in identifying cardiac masses and our multiparametric echocardiographic score could be useful to predict the histological nature of cardiac masses.

Non-invasive detection of acute cell-mediated graft rejection in paediatric heart transplant recipients: the role of cardiovascular magnetic resonance

Background and Aim: Acute cardiac rejection is currently diagnosed by endomyocardial biopsy (EMB), but multiparametric cardiac magnetic resonance (CMR) may be a non-invasive alternative by its capacity for myocardial structure and function characterization. Our primary aim was to determine the utility of multiparametric CMR in identifying acute graft rejection in paediatric heart transplant recipients. The second aim was to compare textural features of parametric maps in cases of rejection versus those without rejection. Methods: Fifteen patients were prospectively enrolled for contrast-enhanced CMR followed by EMB and right heart catheterization. Images were acquired on a 1,5 Tesla scanner including T1 mapping (modified Look-Locker inversion recovery sequence – MOLLI) and T2 mapping (modified GraSE sequence). The extracellular volume (ECV) was calculated using pre- and post-gadolinium T1 times of blood and myocardium and the patient’s hematocrit. Markers of graft dysfunction including hemodynamic measurements from echocardiography, catheterization and CMR were collated. Patients were divided into two groups based on degree of rejection at EMB: no rejection with no change in treatment (Group A) and acute rejection requiring new therapy (Group B). Statistical analysis included student’t t test and Pearson correlation. Results: Acute rejection was diagnosed in five patients. Mean T1 values were significantly associated with acute rejection. A monotonic, increasing trend was noted in both mean and peak T1 values, with increasing degree of rejection. ECV was significantly higher in Group B. There was no difference in T2 signal between two groups. Conclusion: Multiparametric CMR serves as a noninvasive screening tool during surveillance encounters and may be used to identify those patients that may be at higher risk of rejection and therefore require further evaluation. Future and multicenter studies are necessary to confirm these results and explore whether multiparametric CMR can decrease the number of surveillance EMBs in paediatric heart transplant recipients.