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.

Cor Triatriatum Dexter: Contrast Echocardiography Is Key to the Diagnosis of a Rare but Treatable Cause of Neonatal Persistent Cyanosis.

Cor triatriatum dexter (CTD) is an extremely uncommon and underreported congenital cardiac anomaly in which the persistence of the embryonic right venous valve separates the right atrium into two chambers with varying degrees of obstruction to antegrade flow and variable degree of right to left shunt at atrial level. Depending on the size of the valves, clinical manifestations vary from absence of symptoms to severe hypoxia, requiring urgent surgical correction. We herein describe the diagnostic difficulties in a case of neonatal CTD, who developed increasingly severe and unresponsive cyanosis, first interpreted as postnatal maladjustment with pulmonary hypertension. The failure to respond to oxygen and pulmonary vasodilators led us to reconsider a different diagnosis. The use of contrast echocardiography improved the diagnostic performance of transthoracic echocardiogram (TTE) and revealed a massive right-to-left shunt secondary to the presence of an atrial membrane that required urgent surgery.

An alternative valve for mitral valve replacement in young children: using an NO-REACT® INJECTABLE BIOPULMONIC™ prosthesis as a mitral valve replacement in a 14-month-old child.

Mitral valve replacement in infants is challenging and there are limited alternative valves available. Since the Boston group published their first report on alternative valves for mitral valve replacement in infants, there has been a growth in the literature on the topic, mostly based on the use of a stented bovine jugular vein graft (Melody® valve). The challenges of the Melody valve are firstly in its length of 28 mm unexpanded, which has the potential to cause left ventricular outflow tract obstruction, and secondly, the valve needs mechanical dilatation, which is laborious. A modified No-React® Injectable Biopulmonic™ Prosthesis (Bio Integral Surgical, Inc., Mississauga, ON, Canada) which is shorter (19 mm) and simpler in that it is self-expanding was implanted in a 14-month-old child to replace her mitral valve. The operation was successful and the short-term function of the prosthesis is good.

Analysis of a Cooperation and Interventional Model in Humanitarian Medicine.

Background: Every year, around 15 million children, in developing countries, die or develop life-long disabilities because of congenital cardiac diseases. In this report we measure the effect of a pediatric cardiac surgery humanitarian project on the health of the individual and on the potential influence this has on the countries economy and its growing health services. Methods: We collected and analyzed data from the Italian NGO, Mission Bambini's database, including all congenital cardiac missions undertaken in Cambodia between 2012 and 2019. DALY's (Disability Adjusted Life Years) saved by the humanitarian mission were estimated and used to reflect on the impact this had on the populations economy. Progression in the local medical teams skills emulated the advancements made in the health sector of the region. Results: Between 2012 and 2019, 128 patients underwent a congenital cardiac operation at Angkor Hospital for Children at Siem Reap, Cambodia. The median age was 6 years. The majority of the pathologies included VSD, TOF, ASD. The mean Aristotle's Complexity Score was 6. Post-operative mortality was 0.8% (1/128). The cost-effectiveness analysis identified 5.360 DALY's saved by surgery. The competency of the local team was progressive with them being able to handle more complex cases on subsequent missions. Conclusion: In developing Countries, performing congenital cardiac surgery cases can be carried out successfully with improvement in both the economy and the health system of the country by increasing the years and the quality of life of the working population and developing the expertise of the regional team.

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.

Mission Bambini and the "Children's Heart Program": The Challenge of Congenital Heart Disease Among Emergency and Education.

Congenital heart disease is defined as abnormality in the cardiovascular structure or function that is present at birth and it is the most common cause of congenital anomalies. Approximately 90% of more than 1,000,000 children born per year with congenital heart disease worldwide receive suboptimal care or have no access to care at all. Furthermore, the mortality is likely underreported in Low-and Middle-Income Countries. Mission Bambini Foundation is an Italian NGO founded in 2000, aiming at "helping and supporting children who are poor, sick, without education or physically and morally abused" in Italy and worldwide. In 20 years, through 1.700 projects, 1.4 million children have been supported in 75 Countries. In 2005, Mission Bambini launched the "Children's Heart Program," based on long-term partnerships and on medical/surgical volunteering, in order to provide multidisciplinary education and training and technical support.

Mid- to long-term follow-up of pulmonary valve replacement with BioIntegral injectable valve.

OBJECTIVES: Chronic pulmonary valve (PV) regurgitation is a common late sequela after repair of congenital heart diseases like tetralogy of Fallot or pulmonary stenosis, leading to right ventricular dilatation and failure and increased late morbidity and mortality. Timely reoperation may lead to a complete right ventricular recovery. An injectable PV allows pulmonary valve replacement, with or without cardiopulmonary bypass, under direct observation, thereby minimizing the impact of surgery on cardiac function. The aim of this study was to evaluate the feasibility and mid- to long-term clinical outcomes with this device. METHODS: From April 2007 to October 2019, a total of 85 symptomatic patients with severe pulmonary regurgitation or pulmonary stenosis underwent pulmonary valve replacement with an injectable stented pulmonary prosthesis. Data were collected from the international proctoring registry. Mean patient age was 26.7 years. The underlying diagnosis was repaired tetralogy of Fallot in 69.4% patients; moderate or severe pulmonary regurgitation was present in 72.9%. All patients had echocardiographic scans before the operation and during the follow-up period. A total of 54.1% patients also had preoperative/postoperative cardiac magnetic resonance imaging (MRI) or catheterization; 25.9% had off-pump implants. In 53% patients, pulmonary valve replacement was associated with the repair of other cardiac defects. RESULTS: Minor postoperative complications were observed in 10.8% patients. The overall mortality rate was 2.3%; mortality after valve replacement was linked to a severe cardiac insufficiency and it was not related to a prosthesis failure; 1 prosthesis was explanted from 1 patient because of endocarditis, and 6% of patients developed PV stenosis; minor complications occurred in 4.8%. The mean follow-up period was 4.8 years (2 months-12.7 years); 42% of the patients were followed for more than 5 years. Follow-up echocardiography and cardiac MRI showed a significant reduction in RV size and low gradients across the PV. CONCLUSIONS: An injectable PV may be implanted without cardiopulmonary bypass and in a hybrid operating theatre with minimal surgical impact. The bioprosthesis, available up to large sizes, has a low profile, laminar flow and no risk of coronary artery compression. Incidence of endocarditis is rare. The lack of a suture ring permits the implant of a relatively larger prosthesis, thereby avoiding a right ventricular outflow tract obstruction. This device permits future percutaneous valve-in-valve procedures, if needed. Results concerning durability are encouraging, and mid- to long-term haemodynamic performance is excellent.

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.

Factors associated with perioperative mortality in children and adolescents operated for tetralogy of Fallot: A sub-Saharan experience.

BACKGROUND: Patients with tetralogy of Fallot are now surviving to adulthood with timely surgical intervention. However, many patients in low-income countries have no access to surgical intervention. This paper reports the surgical access and perioperative mortality in a sub-Saharan center that was mainly dependent on visiting teams. METHODS: We reviewed records of patients operated from January 2009 to December 2014. We examined perioperative outcomes, primarily focusing on factors associated with perioperative mortality. RESULTS: During this period, 62 patients underwent surgery. Fifty-seven (91.9%) underwent primary repair, while 5 (6.5%) underwent palliative shunt surgery. Of the five patients with shunt surgery, four ultimately underwent total repair. Eight (12.9%) patients died during the perioperative period. Factors associated with perioperative mortality include repeated preoperative phlebotomy procedures (P < .001), repeated runs and long cardiopulmonary bypass time (P < .001), and aortic cross-clamp time (P < .001), narrow pulmonary artery (PA) valve annulus diameter (P = .022), narrow distal main PA diameter (P = .039), narrow left branch PA diameter (P = .049), and narrow right PA diameter (P = .039). Of these factors, cardiopulmonary bypass time/aortic cross-clamp time and pulmonary valve annulus diameter less than three SD were independently associated with perioperative mortality. CONCLUSION: In this series of consecutive patients operated by a variety of humanitarian surgical teams, cardiopulmonary bypass time/aortic cross-clamp time, and pulmonary valve annulus diameter less than three SD were independently associated with perioperative mortality risk. As some of these factors are modifiable, we suggest that they should be considered during patient selection and at the time of surgical intervention.

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.

Palliative Arterial Switch for Congenitally Corrected Transposition of the Great Arteries with Ventricular Septal Defect and Subaortic Hypoplasia.

We present a case of palliative arterial switch with aortic arch reconstruction performed as the first stage of anatomical correction in a patient with congenitally corrected transposition of great arteries (ccTGA), ventricular septal defect (VSD), duct-dependent aortic coartation, and hypoplasia of the ascending aorta and subaortic tract.

Outcome in Children Operated for Membranous Subaortic Stenosis: Membrane Resection Plus Aggressive Septal Myectomy Versus Membrane Resection Alone.

BACKGROUND: The optimal surgical procedure for treatment of fibromembranous subaortic stenosis has been a subject of debate. We report our experience with patients treated for membranous subaortic stenosis using membrane resection alone and membrane resection plus aggressive septal myectomy. METHODS: Patients followed in the pediatric cardiology clinic of a university hospital, who had undergone surgery for subaortic stenosis between 2002 and 2013 were reviewed. Recurrence of subaortic membrane, residual left ventricular outflow gradient, and aortic valve function were analyzed. RESULTS: Forty-six patients underwent surgery for subaortic membrane. Of these, 19 had membrane resection plus aggressive septal myectomy, while 27 had membrane resection alone. Mean age at surgery for the membrane resection group was 7.7 ± 3.9 years and 10.9 ± 3.6 years for the membrane resection plus aggressive myectomy group. Preoperative subaortic gradient for the membrane resection group was 75.5 ± 26.7 mm Hg and 103.2 ± 39.7 mm Hg for the membrane resection plus aggressive myectomy group. The mean follow-up left ventricular outflow tract gradient was 42.3 ± 31.3 mm Hg in the membrane resection group, while it was 11.6 ± 6.3 mm Hg in the aggressive septal myectomy group. Nine patients from the membrane resection group had significant regrowth of the subaortic membrane during the follow-up period, while none of the aggressive septal myectomy group had detectable membrane on echocardiography. Seven of the nine patients with recurrence of the subaortic membrane underwent subsequent membrane resection plus aggressive septal myectomy. Intraoperative finding in all these redo cases was recurrence (growth) of a subaortic membrane. CONCLUSION: Aggressive septal myectomy offers less chance of recurrence, freedom from reoperation, and an improved aortic valve function. This is especially important in sub-Saharan settings where a chance of getting a second surgery is unpredictable.