Recommendations for cardiovascular magnetic resonance and computed tomography in congenital heart disease: a consensus paper from the CMR/CCT Working Group of the Italian Society of Pediatric Cardiology and the Italian College of Cardiac Radiology endorsed by the Italian Society of Medical and Interventional Radiology (Part II).

Cardiovascular magnetic resonance (CMR) and computed tomography (CCT) are advanced imaging modalities that recently revolutionized the conventional diagnostic approach to congenital heart diseases (CHD), supporting echocardiography and often replacing cardiac catheterization. This is the second of two complementary documents, endorsed by experts from the Working Group of the Italian Society of Pediatric Cardiology and the Italian College of Cardiac Radiology of the Italian Society of Medical and Interventional Radiology, aimed at giving updated indications on the appropriate use of CMR and CCT in different clinical CHD settings, in both pediatrics and adults. In this article, support is also given to radiologists, pediatricians, cardiologists, and cardiac surgeons for indications and appropriateness criteria for CMR and CCT in the most referred CHD, following the proposed new criteria presented and discussed in the first document.

The impact of native Fallot anatomy on future therapeutic requirements and outcomes at follow-up.

Background: In patients with repaired Fallot, subsequent surgical or interventional procedures and adverse cardiac events are frequent. We aimed to evaluate the impact of a simple pre-operative anatomic classification based on the size of the pulmonary valve (PV) annulus and branches on future therapeutic requirements and outcomes.

Method: This is a single-center retrospective analysis of patients operated for Fallot before the age of 2 years, from January 1990.

Implications of atrial volumes in surgical corrected Tetralogy of Fallot on clinical adverse events.

Background: While left atrial (LA) size has been shown as a strong predictor of cardiovascular diseases in various studies, the role of right atrial (RA) enlargement, especially in the growing population of patients with congenital heart diseases (CHD) is largely unknown. We sought to evaluate (1) RA and LA volumes in patients with repaired Tetralogy of Fallot (TOF) and assess correlations to (2) functional parameters and (3) clinical adverse events.

Methods: 169 patients with repaired TOF were enrolled following a targeted protocol for Cardiovascular magnetic resonance imaging (CMR), Cardiopulmonary exercise tests (CPET), Echocardiography and Measurement of NT-proBNP.

Isolated pulmonary regurgitation causes decreased right ventricular longitudinal function and compensatory increased septal pumping in a porcine model.

Aim: Longitudinal ventricular contraction is a parameter of cardiac performance with predictive power. Right ventricular (RV) longitudinal function is impaired in patients with free pulmonary regurgitation (PR) following corrective surgery for Tetralogy of Fallot (TOF). It remains unclear whether this is a consequence of the surgical repair, or whether it is inherent to PR.

Impact of percutaneous pulmonary valve implantation for right ventricular outflow tract dysfunction on exercise recovery kinetics.

The recovery of cardiopulmonary variables from peak exercise in patients with pulmonary stenosis (PS) or regurgitation (PR) is delayed, but the impact of treating PS or PR on exercise recovery kinetics is unknown. 43 patients (median age 14 years) with PS (n = 23) or PR (n = 20) after repair of congenital heart disease underwent successful percutaneous pulmonary valve implantation (PPVI). Cardiopulmonary exercise tests (CPET) were performed both before and within 1 month after PPVI.

Measurement of in vitro and in vivo stent geometry and deformation by means of 3D imaging and stereo-photogrammetry.

Purpose: To quantify variability of in vitro and in vivo measurement of 3D device geometry using 3D and biplanar imaging.

Methods: Comparison of stent reconstruction is reported for in vitro coronary stent deployment (using micro-CT and optical stereo-photogrammetry) and in vivo pulmonary valve stent deformation (using 4DCT and biplanar fluoroscopy). Coronary stent strut length and inter-strut angle were compared in the fully deployed configuration.

Geometrical and stress analysis of factors associated with stent fracture after melody percutaneous pulmonary valve implantation.

Background: Patients treated with the Melody device (Medtronic) for percutaneous pulmonary valve implantation experience stent fractures in ≈25% of the cases. The aim of this study is to identify the risk factors associated with fracture using 3-dimensional (3D) analyses.

Methods And Results: In situ 3D shape of the Melody stent was reconstructed from 42 patients using procedural biplane fluoroscopy images, after balloon inflation, at systole and diastole.

Percutaneous pulmonary valve replacement after different duration of free pulmonary regurgitation in a porcine model: effects on the right ventricle.

Background: Free pulmonary regurgitation (PR) after surgical correction of Tetralogy of Fallot (ToF) with transannular patching can lead to irreversible right ventricular (RV) failure. However, the optimal timing of valve replacement is still debated.

Methods And Results: Thirty six pigs were included in the study.

Finite element strategies to satisfy clinical and engineering requirements in the field of percutaneous valves.

Finite element (FE) modelling can be a very resourceful tool in the field of cardiovascular devices. To ensure result reliability, FE models must be validated experimentally against physical data. Their clinical application (e.

Impact of reduction in right ventricular pressure and/or volume overload by percutaneous pulmonary valve implantation on biventricular response to exercise: an exercise stress real-time CMR study.

Aims: To assess the impact of relief of pulmonary stenosis (PS) and pulmonary regurgitation (PR) by percutaneous pulmonary valve implantation (PPVI) on biventricular function during exercise stress.

Methods And Results: Seventeen patients, who underwent PPVI for PS or PR, were included. Magnetic resonance imaging was performed at rest and during supine exercise stress pre- and within 1-month post-PPVI, using a radial k - t SENSE real-time sequence.

Virtual and real bench testing of a new percutaneous valve device: a case study.

Aims: To validate patient-specific computational testing of a second-generation device for percutaneous pulmonary valve implantation (PPVI), against realistic in vitro data.

Methods And Results: Tests were initially carried out in a simple loading mode, performing a compliance test on a rapid prototyped cylinder. This model was reproduced computationally and validated against the experimental data.

Echocardiographic assessment of diastolic biventricular properties in patients operated for severe pulmonary regurgitation and association with exercise capacity.

Aims: We aimed to assess the impact of surgical pulmonary valve replacement (PVR) for severe pulmonary regurgitation (PR) on biventricular function and its effect on exercise capacity.

Methods And Results: Seventy-three patients (mean age 23.6±11.

Patient-specific simulations of transcatheter aortic valve stent implantation.

Transcatheter aortic valve implantation (TAVI) enables treatment of aortic stenosis with no need for open heart surgery. According to current guidelines, only patients considered at high surgical risk can be treated with TAVI. In this study, patient-specific analyses were performed to explore the feasibility of TAVI in morphologies, which are currently borderline cases for a percutaneous approach.

Long-term importance of right ventricular outflow tract patch function in patients with pulmonary regurgitation.

Objective: Chronic pulmonary regurgitation (PR) has deleterious effects on right ventricular (RV) function in repaired tetralogy of Fallot (ToF). However, there are little data regarding right ventricular outflow tract (RVOT) contractile dysfunction in response to chronic PR and on both RV and LV volumes and function.

Methods: We retrospectively identified consecutive patients with PR who were referred for magnetic resonance imaging quantification of "free PR" detected on echocardiography between 2003 and 2008.

Early versus late functional outcome after successful percutaneous pulmonary valve implantation: are the acute effects of altered right ventricular loading all we can expect?

Objectives: The purpose of this study was to assess the potential of late positive functional remodeling after percutaneous pulmonary valve implantation (PPVI) in right ventricular outflow tract dysfunction.

Background: PPVI has been shown to impact acutely on biventricular function and exercise performance, but the potential for further late functional remodeling remains unknown.

Methods: Sixty-five patients with sustained hemodynamic effects of PPVI at 1 year were included.

An assessment of the cost of percutaneous pulmonary valve implantation (PPVI) versus surgical pulmonary valve replacement (PVR) in patients with right ventricular outflow tract dysfunction.

Background: Percutaneous pulmonary valve implantation (PPVI) using the Melody * transcatheter pulmonary valve is a new procedure introduced in 2000 as a less invasive treatment for right ventricular outflow tract (RVOT) dysfunction. The aim of this new procedure is to restore pulmonary valve competence without the need of open-chest operation. By prolonging the conduit lifespan, it delays surgical pulmonary valve replacement (PVR) and it can therefore potentially reduce the number of open-chest interventions over a patient's lifetime.

Electrical remodeling following percutaneous pulmonary valve implantation.

Sudden cardiac death in congenital heart disease is related to increased right ventricular end-diastolic volume (RVEDV), abnormalities of QRS duration, and QRS, JT, and QT dispersions. Surgical pulmonary valve replacement and percutaneous pulmonary valve implantation (PPVI) decrease RVEDV, but the effects of PPVI on surface electrocardiographic parameters are unknown. PPVI represents a pure model of RV mechanical and electrophysiologic changes after replacement.

How do angioplasty balloons work: a computational study on balloon expansion forces.

Aims: To investigate the impact of balloon inflation pressure and balloon diameter on the expansion forces exerted in a stenosed vessel (congenital heart disease applications) using computational models.

Methods And Results: A simplified three-dimensional model of a vessel with a cylindrical stenosis was created. Two low-compliance balloons with different inflation diameters (10 vs.

Pre-stenting with a bare metal stent before percutaneous pulmonary valve implantation: acute and 1-year outcomes.

Objectives: To determine the feasibility and safety of pre-stenting with a bare metal stent (BMS) before percutaneous pulmonary valve implantation (PPVI), and to analyse whether this approach improves haemodynamic outcomes and impacts on the incidence of PPVI stent fractures.

Design: Retrospective analysis of prospectively collected data.

Setting: Tertiary paediatric and adult congenital heart cardiac centre.

MRI may be sufficient for noninvasive assessment of great vessel stents: an in vitro comparison of MRI, CT, and conventional angiography.

Objective: The purpose of this study was to compare the diagnostic performance of MRI and CT assessment of great vessel stents in an in vitro model.

Materials And Methods: Three contemporary great vessel stent materials (nitinol, platinum-iridium, and stainless steel) were assessed with three luminal conditions: no stenosis, internal stenosis, and external stenosis. Stents of the same material were implanted into an aorta model that was attached to an animal bypass pump with pulsatile flow.

Four-dimensional computed tomography: a method of assessing right ventricular outflow tract and pulmonary artery deformations throughout the cardiac cycle.

Objective: To characterise 3D deformations of the right ventricular outflow tract (RVOT)/pulmonary arteries (PAs) during the cardiac cycle and estimate the errors of conventional 2D assessments.

Methods: Contrast-enhanced, ECG-gated cardiovascular computed tomography (CT) findings were retrospectively analysed from 12 patients. The acquisition of 3D images over 10 phases of the cardiac cycle created a four-dimensional CT (4DCT) dataset.

Effects of chronic severe pulmonary regurgitation and percutaneous valve repair on right ventricular geometry and contractility assessed by tissue Doppler echocardiography.

Introduction: Pulmonary regurgitation (PR) following repair of right ventricular (RV) outflow obstruction is related to slowly progressive RV dilatation and heart failure and will eventually require surgical intervention, but optimal timing of pulmonary valve replacement is challenging. Tissue Doppler based quantification of RV contractility may offer additional information in the management of these patients.

Methods: In a porcine animal model free PR was induced by percutaneous stenting of the pulmonary valve orifice (N = 23).

Patient-specific reconstructed anatomies and computer simulations are fundamental for selecting medical device treatment: application to a new percutaneous pulmonary valve.

Nowadays, percutaneous pulmonary valve implantation is a successful alternative to surgery for patients requiring treatment of pulmonary valve dysfunction. However, owing to the wide variety of implantation site morphology, size and dynamics, only about 15 per cent of cases are suitable for current devices. In order to increase the number of patients who could benefit from minimally invasive procedures, a new valved stent graft for percutaneous implantation has been designed recently.