1,721,018 research outputs found
Sviluppo del miocardio fetale: impatto dell'orientamento delle fibre sulla funzione diastolica del ventricolo sinistro
Full text linkObiettivi: Scopo dello studio è di migliorare la comprensione dei meccanismi evolutivi che promuovono lo sviluppo dell’architettura miocardica del ventricolo sinistro, confrontando i dati anatomici ottenuti con l’esame istologico del miocardio fetale alle differenti settimane di gestazione con i dati funzionali calcolati all’ecocardiografia fetale mediante metodica speckle tracking.
Materiali e metodi: in questo studio trasversale sono stati al momento arruolati 72 feti di età gestazionale compresa tra le 17 e le 36 settimane gestazionali e 39 neonati in prima giornata di vita nati dopo 23-36 settimane di gestazione. Di questi pazienti è stata ottenuta una proiezione apicale 4 camere da cui è stato possibile studiare il valore di strain longitudinale regionale sia a livello dell’endocardio sia a livello dell’epicardio.
Sono stati inoltre analizzati i cuori di 20 feti sottoposti ad indagine autoptica per aborto spontaneo o interruzione volontaria di gravidanza senza patologia cardiaca. Di questi sono state ottenute delle fette di miocardio ventricolare sinistro da tagli longitudinali e sagittali a livello della parete laterale del ventricolo sinistro.
Sulla base dei risultati funzionali ed istologici sono stati progettati, in collaborazione con il Dipartimento di Ingegneria Civile, Ambientale e Strutturale, ricostruzioni al computer di curve pressione-volume durante la fase diastolica in funzione della diversa prevalenza di espressione delle fibre miocardiche.
Sviluppo del progetto: Il progetto ha coinvolto l’UOC di Cardiologia Pediatrica, l’UOC di Patologia Neonatale, l’UOC di Anatomia Patologica e il Dipartimento di Ingegneria Civile, Ambientale e Strutturale dell’Università di Padova. Lo sviluppo di questo progetto si è avvalso della collaborazione della Prof. Annalisa Angelini e della Dott.ssa Marny Fedrigo afferenti alla UOC di Anatomia Patologica; della Prof.ssa Francesca Susin, della Prof.ssa Daniela Boso, del Dott. Paolo Peruzzo e della Dott.ssa Elena De Filippi, afferenti al Dipartimento di Ingegneria, per l’implementazione del modello matematico per la customizzazione della curva di Frank-Starling nei diversi pattern di distribuzione delle fibre miocardiche; della Dott.ssa Valentina Favero (acquisizione dati dei neonati afferenti alla UOC di Patologia Neonatale) e delle studentesse Alessia Basso (acquisizione dati ecografici del feto) e Irene Cattapan (acquisizione ed analisi dei dati ecografici del feto e dei dati di Anatomia Patologica)
Risultati: Lo studio ha dimostrato che i fasci longitudinali endocardici si differenziano precocemente rispetto ai fasci longitudinali epicardici. Infatti i primi rappresentano il 50% dello spessore miocardico già alla 14° settimana, e tale valore risulta stabile lungo il resto della gestazione. I fasci epicardici, invece, si differenziano alle spese dei quelli mesocardici trasversi solo tardivamente, passando dal 5% della 14° settimana al 22% al termine della gestazione. Dal punto di vista funzionale tale ripartizione è confermata dal rapporto tra lo strain longitudinale epicardico rispetto a quello endocardico, che passa dal 55% alla 18° settimana al 70% al termine della gestazione.
Il lavoro in vitro ha permesso di evidenziare il comportamento delle curve pressione-volume a seconda della diversa disposizione delle fibre. È stato dimostrato che se le fibre si dispongono in senso radiale aumenta la compliance diastolica del ventricolo, mentre man mano che le fibre assumono un assetto longitudinale il sistema diventa più rigido. In condizioni fisiologiche le fibre hanno una disposizione +/- 60°. Tale livello di ridigità assicura contenute variazioni di volume a differenti condizioni di carico. Durante la vita fetale, invece, il sistema parte da una disposizione prevalentemente orizzontale, probabilmente perché le pressioni da generare sono più basse e perché la camera ventricolare ha rapidi incrementi di volume legati alla crescita.
È stato inoltre verificato che il sistema risulta più rigido se lo strato longitudinale è posto all’endocardio, questo è ciò che si verifica nel feto a partire dalla 12° settimana di gestazione.
Conclusioni: questo studio dimostra i meccanismi meccanici e idraulici che sottendono allo sviluppo del miocardio fetale e pone le basi per lo studio dei meccanismi di compenso che si sviluppano nei pazienti con scompenso cardiaco.
Prospettive future: sarebbe utile sviluppare la curva pressione-volume anche in fase sistolica per determinare la performance delle fibre in fase contrattile
Successful transvenous mechanical lead extraction and stent implantation in a patient after Mustard palliation for D-transposition of great arteries and superior vena cava syndrome
No full textWe report a successful combined approach of transvenous mechanical pacing lead extraction and stent angioplasty for superior baffle occlusion in a young woman with D-transposition of great artery after Mustard procedure. After having extracted the pacing leads, the baffle was easily stented, thanks to the channel left by the extracted leads. Eventually, a new pacing lead was implanted into the pulmonic ventricle through the stented baffle. Our report demonstrates the safeness and feasibility of a combined interventional approach in avoiding the need for surgery
Multi-district coronary tree involvement in a 17-year-old girl with Williams–Beuren syndrome
Full text linkAlternative techniques of right ventricular outflow tract reconstruction for surgical repair of truncus arteriosus
No full textOBJECTIVES: This study aimed to evaluate the outcomes and feasibility of different techniques of reconstruction of the right ventricular outflow tract (RVOT) in surgical repair of truncus arteriosus. METHODS: We retrospectively reviewed all consecutive patients with truncus arteriosus who underwent successful surgical repair in our centre between 1994 and 2017. We analysed late results according to the type of RVOT repair. RESULTS: We collected data from 29 survivors after truncus arteriosus repair. Six (20%) of them were affected by DiGeorge syndrome. The RVOT reconstruction was achieved using a valved conduit in 58.6%, while a direct right ventricle-pulmonary artery (RV-PA) anastomosis, with or without the interposition of the left atrial appendage, was performed in the remaining. At a median follow-up time of 7.9 years (interquartile range 1.8-13.1), 6 patients (3 affected by DiGeorge syndrome) died. Between the 2 groups, there were no differences in terms of the late mortality and onset of adverse events. However, the use of a conduit seemed more prone to reintervention and onset of adverse events. CONCLUSIONS: Different RVOT reconstruction techniques are safe and have similar late outcomes. However, use of a direct RV-PA anastomosis and left atrial appendage interposition may reduce the need for reoperation in the long term
Transcatheter Pulmonary Valve Implantation: A State of the Art Review
No full textCongenital heart disease (CHD) affects about 1% of live births. Among them, about 20% will undergo one or more surgical or percutaneous maneuvers on the right ventricle outflow tract or pulmonary valve. Transcatheter pulmonary valve implantation is a recently available less invasive alternative to surgery for treatment of right ventricular outflow tract dysfunction. Thus, residual dysfunction can be treated early and with a lower risk profile. This narrative review aimed to describe the state of the art of percutaneous pulmonary valve implantation
Preservation of the Pulmonary Valve During Early Repair of Tetralogy of Fallot: Surgical Techniques
No full textDuring the last decade interest in preserving pulmonary valve (PV) function has stimulated a few surgeons to apply valve-sparing techniques in repairing tetralogy of Fallot (TOF), with the aim of preserving long-term right ventricular function. Since June 2007, we embarked upon a program for preserving PV function in selected patients during TOF repair. More recently, the introduction of more complex PV plasty techniques allowed us to further extend the applicability of PV preservation techniques. We believe that preservation of PV function during early repair of TOF, by combining different intraoperative surgical maneuvers, can be extended to almost all patients with classic TO
Late Electrical and Mechanical Remodeling After Atrial Septal Defect Closure in Children: Surgical Versus Percutaneous Approach
No full textEarly Correction of Common Atrioventricular Septal Defects: A Single-Center 20-Year Experience
No full textBackground. Over the past 20 years our policy has been to electively repair common atrioventricular canal defects (CAVCD) in patients between 8 and 12 weeks of age. We sought to evaluate the results of our past 20-year experience.
Methods. From January 1992 to April 2014, 159 consecutive patients underwent CAVCD repair (133 patients had complete CAVCD and 26 patients had a transitional form of CAVCD).
Results. Surgical repair was accomplished with a double-patch (n =137 [86%]) or a modified single patch (n = 22 [14%]) technique. Median age at operation was 96 days (interquartile range [IQR], 73-128 days); 90 patients were younger than 3 months of age. There were 3 operative (1.9%) and 12 late (7.7%) deaths. Median follow-up time after repair was 8.2 years (IQR, 3.6-15 years). Twenty patients (13%) required reoperation-16 (10%) for left atrioventricular valve (LAVV) regurgitation. Reoperation on the LAVV was more frequent in patients with a dysplastic LAVV preoperatively (p = 0.01; odds ratio [OR], 4.2; 95% confidence interval [CI], 1.33-13.5) and in patients who underwent closure for an absent/ incomplete cleft at the time of repair (p = 0.01; OR, 5.4; 95% CI, 1.4-21). Late LAVV performance (regurgitation greater than or equal to moderate or the need for reoperation), including late deaths and patients who underwent reoperation, was significantly worse in patients older than 3 months at repair (10 of 83 patients [12%] versus 20 of 73 patients [27%]; hazard ratio [HR], 2.71; 95% CI, 1.19-6.19) and in patients with LAVV dysplasia (19 of 68 patients [28%] versus 11 of 88 patients [12%]; HR, 3; 95% CI, 1.53-8.51).
Conclusions. Individualized early repair of CAVCD is safe and beneficial, with good early and long-term results. (C) 2016 by The Society of Thoracic Surgeon
Systemic sclerosis sine scleroderma in children
No full textOBJECTIVE: Juvenile systemic sclerosis (JSSc) is a rare condition in childhood and its variety with no skin involvement, sine scleroderma (ssJSSc), is anecdotal. We report the first case series of patients with ssJSSc. METHODS: Demographic, clinical and laboratory data of patients with JSSc followed at our centre were retrospectively collected. Patients with no skin involvement but with all of the features RP, positive ANA, intestinal dysmotility and/or interstitial lung disease (ILD) or pulmonary arterial hypertension (PAH) and/or cardiac or renal involvement typical of scleroderma were defined as having ssJSSc and compared with those with classic JSSc (cJSSc). RESULTS: Among 52 JSSc patients seen in 20 years, five (9.6%) presented with ssJSSc. Their clinical features and those of the only two patients reported in the literature so far were compared with classic JSSc with available complete data. Six patients had cardiac involvement as presenting feature, three primary cardiomyopathy, three secondary to PAH. Two patients died after a brief disease course and one rapidly underwent heart transplantation. In comparison with cJSSc, ssJSSc showed a significantly longer diagnostic delay (20.1 vs 8.3 months, P = 0.017), higher frequency of cardiac involvement (85.7 vs 15.6%, P = 0.001) and worse outcome, intended as mortality or end-stage organ failure rates (42.9% vs 6.2%, P < 0.001). CONCLUSION: Cardiac involvement represents the most important characteristic of ssJSSc and carries a high morbidity and mortality rate. The longer delay in diagnosis underlines the need for a comprehensive rheumatological work-up in patients with isolated cardiomyopathy or PAH/ILD
Three-Dimensional printing for hybrid closure of complex muscular ventricular septal defects
No full textThe identification and surgical closure of apical complex muscular ventricular septal defects (CMVSD) remains a difficult problem because of their location in the ventricular septum distal to the moderating band
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