Computational haemodynamics for pulmonary valve replacement by means of a reduced fluid-structure interaction model.

Pulmonary valve replacement (PVR) consists of substituting a patient's original valve with a prosthetic one, primarily addressing pulmonary valve insufficiency, which is crucially relevant in Tetralogy of Fallot repairment. While extensive clinical and computational literature on aortic and mitral valve replacements is available, PVR's post-procedural haemodynamics in the pulmonary artery and the impact of prosthetic valve dynamics remain significantly understudied. Addressing this gap, we introduce a reduced Fluid-Structure Interaction (rFSI) model, applied for the first time to the pulmonary valve. This model couples a three-dimensional computational representation of pulmonary artery haemodynamics with a one-degree-of-freedom model to account for valve structural mechanics. Through this approach, we analyse patient-specific haemodynamics pre and post PVR. Patient-specific geometries, reconstructed from CT scans, are virtually equipped with a template valve geometry. Boundary conditions for the model are established using a lumped-parameter model, fine-tuned based on clinical patient data. Our model accurately reproduces patient-specific haemodynamic changes across different scenarios: pre-PVR, six months post-PVR, and a follow-up condition after a decade. It effectively demonstrates the impact of valve implantation on sustaining the diastolic pressure gradient across the valve. The numerical results indicate that our valve model is able to reproduce overall physiological and/or pathological conditions, as preliminary assessed on two different patients. This promising approach provides insights into post-PVR haemodynamics and prosthetic valve effects, shedding light on potential implications for patient-specific outcomes.

Impact of COVID-19 Pandemic on the Italian Humanitarian Congenital Cardiac Surgery Activity: What No One Tells You.

More than 4 millions of children with congenital heart disease (CHD) are waiting for cardiac surgery around the world. Few of these patients are treated only thanks to the support of many non-governmental organizations (NGOs). Starting in December 2019, the so-called coronavirus disease 2019 (COVID-19) has rapidly become a worldwide pandemic and has dramatically impacted on all the international humanitarian activities for congenital heart disease. We analyzed data from all the Italian congenital cardiac surgery centers with the aim to quantify the impact of the pandemic on their charities. Fifteen Italian centers participated in the study and contributed to data collection. We analyzed and compared data regarding humanitarian activities carried out abroad and on site from two periods: year 2019 (pre-COVID-19) and year 2020 (COVID-19 pandemic). In 2019, 53 international missions were carried out by Italian congenital cardiac surgeons, resulting in the treatment of 471 CHD patients. In the same period 11 Italian cardiac centers operated on 251 foreign patients in Italy. In 2020, the pandemic led to a reduction of this activity by 96% for the surgery performed overseas and 86% for the interventions carried out in Italy. In conclusion our study shows the important quantitative impact of the pandemic on the Italian humanitarian cardiac surgical activity overseas and in Italy. This shocking result highlights the failure of the systems adopted so far to solve the problem of CHD in developing countries.

Switch from minimally invasive biventricular mechanical support to cardiopulmonary bypass during heart transplant.

An easily reproducible surgical technique to switch from percutaneous minimally invasive biventricular mechanical support to cardiopulmonary bypass during heart transplantation is illustrated. After cannulation of the distal ascending aorta with a standard arterial cannula, the ProtekDuo® cannula and the ProtekSolo® Transseptal cannula were partially retracted to reach the superior and inferior vena cava, respectively, and connected to the pump circuit for the venous drainage. With this cardiopulmonary bypass configuration, orthotopic heart transplantation was routinely performed and, at the end of the procedure, the 2 cannulas were uneventfully removed.

Impact of the coronavirus disease 2019 (COVID-19) pandemic on the Italian congenital cardiac surgery system: a national survey.

OBJECTIVES: Italy has been one of the countries most severely affected by the coronavirus disease 2019 (COVID-19). The Italian government was forced to introduce quarantine measures quickly, and all elective health services were stopped or postponed. This emergency has dramatically changed the management of paediatric and adult patients with congenital heart disease. We analysed data from 14 Italian congenital cardiac surgery centres during lockdown, focusing on the impact of the pandemic on surgical activity, patients and healthcare providers and resource allocation. METHODS: Fourteen centres participated in this study. The period analysed was from 9 March to 4 May. We collected data on the involvement of the hospitals in the treatment of patients with COVID-19 and on limitations on regular activity and on the contagion among patients and healthcare providers. RESULTS: Four hospitals (29%) remained COVID-19 free, whereas 10 had a 39% reduction in the number of beds for surgical patients, especially in the northern area. Two hundred sixty-three surgical procedures were performed: 20% elective, 62% urgent, 10% emergency and 3% life-saving. Hospital mortality was 0.4%. Compared to 2019, the reduction in surgical activity was 52%. No patients operated on had positive test results before surgery for severe acute respiratory syndrome coronavirus 2, the virus responsible for COVID-19. Three patients were infected during the postoperative period. Twenty-nine nurses and 12 doctors were infected. Overall, 80% of our infected healthcare providers were in northern centres. CONCLUSIONS: Our study shows that the pandemic had a different impact on the various Italian congenital cardiac surgery centres based on the different patterns of spread of the virus across the country. During the lockdown, the system was able to satisfy all emergency clinical needs with excellent results.

Lombardy regional urgent reorganization for congenital cardiac patients following the Covid-19 pandemic.

OBJECTIVE: By the end of February 2020, the COVID-19 pandemic infection had spread in Northern Italy, with thousands of patients infected. In Lombardy, the most affected area, the majority of public and private hospitals were dedicated to caring for COVID-19 patients and were organized following the 'Hub-and-Spoke' model for other medical specialties, like cardiac surgery and interventional procedures for congenital cardiac disease (CHD). Here, we report how the congenital cardiac care system was modified in Lombardy and the first results of this organization. METHODS: We describe a modified 'Hub-and-Spoke' model - that involves 59 birthplaces and three specialized Congenital Cardiac Centers -- and how the hub center organized his activity. We also reported the data of the consecutive cases hospitalized during this period. RESULTS: From 9 March to 15 April, we performed: a total of 21 cardiac surgeries, 4 diagnostic catheterizations, 3 CT scans, and 2 CMR. In three cases with prenatal diagnosis, the birth was scheduled. The spoke centers referred to our center six congenital cardiac cases. The postop ExtraCorporeal Membrane Oxygenation support was required in two cases; one case died. None of these patients nor their parents or accompanying person was found to be COVID-19-positive; 2 pediatric intensivists were found to be COVID-19-positive, and needed hospitalization without mechanical ventilation; 13 nurses had positive COVID swabs (4 with symptoms), and were managed and isolated at home. CONCLUSION: Our preliminary data suggest that the model adopted met the immediate needs with a good outcome without increased mortality, nor COVID-19 exposure for the patients who underwent procedures.

Cangrelor use in a 6-year-old patient undergoing complex percutaneous coronary intervention after post-surgical myocardial infarction.

Cangrelor is an intravenously administered P2Y12 receptor antagonist, which has been approved for adult patients undergoing percutaneous coronary intervention and, due to its unique pharmacokinetics, it allows effective and controllable peri-procedural platelet inhibition. We report the case of a 6-year-old child with anomalous origin of right coronary artery from aortic left coronary sinus, who underwent elective surgical replacement of stenotic and calcified conduit between the right ventricle and the main pulmonary artery. The surgery was complicated by acute myocardial infarction secondary to coronary extrinsic compression. The patient was successfully treated with urgent percutaneous coronary intervention (simultaneous V-stenting) and cangrelor infusion, subsequently switched to clopidogrel therapy.

The role of primary surgical repair technique on late outcomes of Tetralogy of Fallot: a multicentre study.

OBJECTIVES: Repair of Tetralogy of Fallot (TOF) has currently excellent results with either transventricular or transatrial approach. However, it is unclear as to which has better late outcomes and what role of residual pulmonary valve (PV) regurgitation in the long term is. We report on late clinical outcomes after repair in a large series of patients with TOF, focusing on the type of surgical technique. METHODS: This analysis is a retrospective multicentre study on patients undergoing TOF repair in infancy. The exclusion criteria of the study were TOF with pulmonary atresia or absent PV. RESULTS: We selected 720 patients who had undergone TOF repair (median age 5.7 months, interquartile range 3.7-11.7). Preoperative cyanotic spells occurred in 18%. A transatrial repair was performed in 433 (60.1%) patients. The PV was preserved in 249 (35%) patients, while the right ventricular outflow tract was reconstructed with a transannular patch (60.4%) or a conduit (4.6%) in the rest of the patients. At a median follow-up of 4 years (range 1-21, 86% complete), 10 (1.6%) patients died, while 39 (6.3%) patients required surgical reoperation and 72 (11.7%) patients required an interventional procedure. The propensity match analysis showed that the incidence of postoperative complications and adverse events at follow-up were significantly increased in patients undergoing transventricular approach repair with transannular patch (P = 0.006) and PV preservation was a significant protective factor against postoperative complications (P = 0.009, odds ratio 0.5) and late adverse events (P = 0.022). CONCLUSIONS: Surgical repair of TOF in infancy is a safe procedure, with good late clinical outcomes. However, transatrial approach and PV preservation at repair are associated with lower early and late morbidity.

Italian survey on cardiac surgery for adults with congenital heart disease: which surgery, where and by whom?

OBJECTIVES: The population of ageing adults with congenital heart disease (ACHD) is increasing; surgery in these patients presents major difficulties in management. A great debate has developed about whether these patients should be cared for at an adult or paediatric hospital and by an acquired or congenital cardiac surgeon. We analysed data of the surgical treatment of ACHD from the Italian cardiac surgery centres in 2016, focusing on the type of surgery performed, where these patients were operated on and by whom. METHODS: Ninety-two Italian cardiac surgery centres were contacted and 70 centres participated in this study. We collected data on the types of cardiac operations performed in congenital heart defect patients older than 18 years. In 2016, a total of 913 patients with ACHD were operated on: 440 by congenital cardiac surgeons (group I) in centres with paediatric and adult cardiac surgery units, and 473 by adult cardiac surgeons (group II) in centres with exclusively adult cardiac surgery units. RESULTS: Pathologies of the right ventricular outflow tract were the most frequent diseases treated in group I and pathologies of the left ventricular outflow tract in group II. Group I included more complex and heterogeneous cases than group II. Surgery for ACHD represented 12% of the activity of congenital cardiac surgeons and only 1% of the activity of adult cardiac surgeons. CONCLUSIONS: In Italy, ACHD patients are operated on both by congenital and adult cardiac surgeons. Congenital cardiac surgeons working in centres with both paediatric and adult cardiac surgery are more involved with ACHD patients and with more complex cases.

Epicardial cardioverter-defibrillator implantation in a 4-month-old infant bridged to heart transplantation.

Implantable cardioverter-defibrillator (ICD) is the gold standard therapy for the prevention of sudden cardiac death. Nevertheless, ICD placement in the paediatric population is still limited because of several technical difficulties. Several implantation techniques have been proposed but experience in infants with very low weight and less than 6 months is very limited. We herein describe a case of a minimally invasive ICD epicardial implantation in a 4-month-old infant weighing 5 kg. A diagnosis of arrhythmic cardiomyopathy with left ventricular non-compaction disease with ventricular tachycardia storms, QT prolongation and Wolff-Parkinson-White pattern was made. Antiarrhythmic drugs, radiofrequency ablation and sympathetic denervation were not effective. ICD implantation was successful allowing the infant to survive and bridging to heart transplantation.

Off-pump Kommerell's diverticulum resection and descending aorta replacement.

We report the case of an unusual variation of a Kommerell's diverticulum in a left aortic arch with an aberrant left subclavian artery, associated with dilatation of the distal aortic arch, surgically treated without the use of extracorporeal circulation.

[A matter of perspective: multimodality imaging of a giant cardiac mass]. / Questione di prospettiva: imaging multimodale di una massa cardiaca gigante.

A newborn was suspected of having situs inversus with levocardia based on chest X-ray. Echocardiography ruled out this hypothesis but revealed a giant cardiac mass that was confirmed by magnetic resonance imaging. Coronary angiography showed that the right coronary artery ran on the surface of the mass, and only partial debulking surgery was performed to relieve right heart compression. Histological examination classified the mass as cardiac fibroma. Complex diagnostic work-up allowed correct anatomic definition of the mass as well as its relationship with adjacent structures, and helped guide surgical planning.

[Transposition of the great arteries]. / La trasposizione delle grandi arterie.

Dextro-transposition of the great arteries with intact ventricular septum (d-TGA) is the most frequent cyanotic congenital heart disease in neonates. In newborns affected by d-TGA, the pulmonary and systemic circulations are in parallel instead of being in series. The survival of babies affected by d-TGA is related to the level of mixing at the patent foramen ovale. The diagnosis of d-TGA is an indication for treatment due to scarce survival beyond the neonatal period if not corrected. The current surgical approach is the anatomical correction with the arterial switch operation, which has excellent early and medium-term results. In this review, we discuss treatment of d-TGA and the arterial switch operation, the medium- and long-term results following surgery, and the reasons that have led the arterial switch operation to its popularity compared to the former physiological correction of d-TGA, i.e. the Senning and Mustard procedures.

Two decades of experience with the Ross operation in neonates, infants and children from the Italian Paediatric Ross Registry.

OBJECTIVE: Children undergoing Ross operation were expected to have longer autograft, but shorter homograft durability compared with adults. In order to define the outcome in the second decade after Ross operation in children, a nationwide review of 23 years of experience was undertaken. METHODS: 305 children underwent Ross operation in 11 paediatric units between 1990 and 2012. Age at surgery was 9.4±5.7 years, indication aortic stenosis in 103 patients, regurgitation in 109 and mixed lesion in 93. 116 (38%) patients had prior procedures. Root replacement was performed in 201 patients, inclusion cylinder in 14, subcoronary grafting in 17 and Ross-Konno in 73. RESULTS: There were 10 (3.3%) hospital and 12 late deaths (median follow-up 8.7 years). Survival was 93±2% and 89±3% and freedom from any reoperation was 76±3% and 67±6% at 10 and 15 years. 34 children had autograft 37 reoperations (25 replacement, 12 repair): three required transplantation after reoperation. Freedom from autograft reoperation was 86±3% and 75±6% at 10 and 15 years. 32 children had right heart redo procedures, and only 25 (78%) conduit replacements (15-year freedom from replacement, 89±4%). Prior operation (p=0.031), subcoronary implant (p=0.025) and concomitant surgical procedure (p=0.004) were risk factors for left heart reoperation, while infant age (p=0.015) was for right heart. The majority (87%) of late survivors were in NYHA class I, 68% free from medication and six women had pregnancies. CONCLUSIONS: Despite low hospital risk and satisfactory late survival, paediatric Ross operation bears substantial valve-related morbidity in the first two decades. Contrary to expectation, autograft reoperation is more common than homograft.

Surgical repair of left ventricle to coronary sinus fistula complicating mitral valve replacement.

We report the case of a 55-year-old female patient who underwent reoperation because of left ventricular to coronary sinus fistula following previous mitral valve replacement. The fistula was closed surgically with a patch of heterologous bovine pericardium. The postoperative course was uneventful and the patient is recovering well 12 months after the operation.