Mechanically Assisted Total Cavopulmonary Connection With an Axial Flow Pump: Computational and In Vivo Study.

A relevant number of patients undergoing total cavopulmonary connection (TCPC) experience heart failure (HF). Heart transplant is then the final option when all other treatments fail. The axial flow blood pumps are now the state of the art; however, there is little experience in low-pressure circuits, such as support of the right ventricle or even a TCPC circulation. A new T-shaped model of mechanically assisted TCPC using the "Jarvik Child 2000" axial pump, (flow rates between 1 and 3 L/m in a range of 5000-9000 rpm) was designed, simulated numerically, and then tested in animals. Eight sheep (42-45 kg) were studied: two pilot studies, four pump-supported (PS) TCPC for 3 h, and two not pump-supported (NPS) TCPC. In the PS, the axial pump was set to maintain the baseline cardiac output (CO). Pressures, CO, systemic and pulmonary vascular resistance, lactate levels, and blood gases were recorded for 3 h. Computational fluid dynamics (CFD) study allows us to set the feasible operating condition and the safety margins to minimize the venous collapse risk. In the NPS animals, a circulatory deterioration, with increasing lactate level, occurred rapidly. In the PS animals, there was a stable cardiac index of 2.7 ± 1.4 L/min/m(2), central venous pressure of 12.3 ± 1 mm Hg, and a mean pulmonary artery pressure (PAP) of 18.1 ± 6 after 3 h of support up to 9000 rpm. systemic vascular resistance (SVR), pulmonary vascular resistance (PVR), blood gasses, and arterial lactate levels remained stable to baseline values. No caval collapse occurred. A new pediatric axial flow pump provides normal CO and physiologic stability in a new T-shaped model of TCPC in sheep, in vivo. CFD and in vivo data showed that this experimental arrangement will allow us to evaluate the potential for mechanical support in patients with Fontan failure avoiding major adverse events.

Outcome of Standard and Bicuspidalized Cryopreserved Homografts for Primary Right Ventricular Outflow Tract Reconstruction.

BACKGROUND AND AIM OF THE STUDY: The study aim was to analyze the safety and longevity of cryopreserved homografts used for primary right ventricular outflow tract reconstruction (RVOTR), and to compare the outcome using either standard or bicuspidalized allografts. METHODS: Between February 2000 and September 2014, a total of 53 patients underwent primary RVOTR using either a standard (n = 40) or a bicuspidalized (n = 13) cryopreserved homograft. The median age at surgery was 15.5 months (range: 1-419.06 months), and bodyweight was 8.5 kg (range: 4.1-71 kg). The median standard homograft size was 17.5 mm (range: 10-25 mm), while the median bicuspidalized homograft size was 16 mm (range: 14-22 mm). Follow up was complete in 91.4% of patients, with a median duration of 30.11 months (range: 0.26-161.26 months). Data analysis included primary diagnosis, type of surgery, age at surgery, size of conduit, need for reintervention, and survival. Predetermined primary outcomes were represented by survival and freedom from conduit reintervention. RESULTS: Two patients with standard cryopreserved homograft died. during the early postoperative period (3.7%). No deaths were conduit-related. The five-year survival rate and ten-year freedom from reintervention were 91% (range: 74.7-97.2%) and 53.6% (range: 97-33.2%), respectively. RV-PA conduit replacement was performed in 14 patients (26.4%) at a median interval of 44.5 months (range: 14.93-162.46 months). Among these patients, four children (30.7%) received bicuspidalized homografts, and 10 (25%) received standard homografts. Causes of reintervention were conduit stenosis in six cases (43%), severe homograft valve regurgitation in two (14.2%), conduit stenosis and homograft valve regurgitation in two (14.2%), and stenosis of distal anastomosis involving pulmonary bifurcation in four (28.6%). Univariate analyses showed a longer freedom from reintervention for bicuspidalized compared to standard homograft (p = 0.03). CONCLUSION: The results obtained suggested that bicuspidalized homograft performance compares well with that of standard allografts in terms of freedom from reintervention. Bicuspidalized homograft use is strongly indicated for primary RVOTR in small children, when a standard homograft of appropriate size is not available.

Interleukin 6 activity associated with a cardiac lymphoma.

Primary cardiac B-cell lymphoma is an extremely rare heart tumor that may be difficult to diagnose because of nonspecific clinical manifestations. Cardiac myxomas and mediastinal lymphomas show increased levels of serum cytokines, which correlate with symptoms and tumor size. We present a case of an intracardiac large B-cell lymphoma in a 75-year-old woman who had high serum levels of interleukin 6 that decreased after tumor excision. These data suggest a possible correlation between cardiac B lymphoma symptoms and interleukin 6 overproduction.

Synergy of cytological methods in the pathological staging of breast cancer: Axillary fine-needle aspiration and intraoperative scrape cytology of the sentinel lymph node.

BACKGROUND: Sentinel lymph node biopsy (SLNB) has become the standard in breast cancer staging, but it is costly and time-consuming. Fine-needle aspiration cytology (FNAC) under ultrasonographic guidance identifies patients who need axillary lymph-node dissection (ALND), thus reducing costs. As an alternative to frozen sections (FS), intraoperative scrape cytology (ISC) for SLNB is an inexpensive, rapid, accurate and safe technique. We evaluated the synergy of FNAC and SLNB in determining the axillary burden and the performance of the ISC method. METHODS: Over a nine-year period, 894 breast cancer patients were analyzed. Of these, 439 patients with echographic suspicious nodes underwent preoperative FNAC; negative axillary ultrasounds or FNACs resulted in 606 intraoperative SLNB, performed using the ISC technique. The results were compared with histological diagnosis, and sensitivity, specificity, predictive values and accuracy were calculated. RESULTS: Of the 439 FNACs, 121 were positive and underwent immediate ALND, and 242 negative patients underwent intraoperative SLNB (69% sensitivity, 99% specificity). Positive cases often had multiple nodal involvement (55% pN2-3). Of the 606 SLNB-ISC smears, 510 were true negative; 65 true positives allowed for one-step ALND (71% sensitivity, 99% specificity). CONCLUSION: Preoperative positive axillary FNAC predicts a higher disease burden and determines the avoidance of SLNB for patients eligible for immediate ALND. ISC instead of FS is a safe and sensitive technique to identify metastases, indicating completion of ALND. PARTIALLY PRESENTED AT: Joint International Oncology (sentinel node & cancer metastasis) Congress, May 27-29, 2013, San Francisco, California, USA 18 ° International Congress of Cytology (ICC 2013-1161), May 26-30, 2013, Paris, France Convegno Nazionale GISMa - Finalborgo (Savona), Italy,19-20 maggio 2016.

The Use of Berlin Heart EXCOR VAD in Children Less than 10 kg: A Single Center Experience.

Objective: Despite the improvement in ventricular assist device (VAD) therapy in adults and in adolescents, in infant population only Berlin Heart EXCOR (BHE) is licensed as long term VAD to bridge children to Heart Transplantation (HTx). Particularly demanding in terms of morbidity and mortality are smallest patients namely the ones implanted in the first year of life or with a lower body surface area. This work aims at retrospective reviewing a single center experience in using BHE in children with a body weight under 10 kg. Methods: Data of all pediatric patients under 10 kg undergoing BHE implantation in our institution from March 2002 to March 2016 were retrospectively reviewed. Results: Of the 30 patients enrolled in the study, 53% were male, 87% were affected by a dilated cardiomyopathy with an average weight and age at the implantation of 6.75 ± 2.16 Kg and 11.57 ± 10.12 months, respectively. Three patients (10%) required a BIVAD implantation. After the implantation, 7 patients (23%) required re-intervention for bleeding and 9 patients (30%) experienced BHE cannulas infection. A total of 56 BHE pump were changed for thrombus formation (1.86 BHE pump for patient). The average duration of VAD support was 132.8 ± 94.4 days. Twenty patients (67%) were successfully transplanted and 10 patients (33%) died: 7 for major neurological complication and 3 for sepsis. Conclusion: Mechanical support in smaller children with end stage heart failure is an effective strategy for bridging patients to HTx. The need for BIVAD was relegated, in the last years, only to restrictive cardiomiopathy. Further efforts are required in small infants to improve anticoagulation strategy to reduce neurological events and BHE pump changes.

Outcome of mechanical cardiac support in children using more than one modality as a bridge to heart transplantation.

OBJECTIVES: Mechanical cardiac support (MCS) can successfully be applied as a bridging strategy for heart transplantation (OHTx) in children with life-threatening heart failure. Emergent use of MCS is often required before establishing the likelihood of OHTx. This can require bridge-to-bridge strategies to increase survival on the waiting list. We compared the outcome of children with heart failure who underwent single MCS with those who required multiple MCS as a bridge to OHTx. METHODS: A retrospective study of patients aged less than 16 years was conducted. From March 1998 to October 2005, we used either a veno-arterial extracorporeal membrane oxygenator (VA-ECMO), or the Medos® para-corporeal ventricular assist device (VAD). From November 2005 onwards, the Berlin Heart EXCOR® (BHE) device was implanted in the majority of cases. Several combinations of bridge-to-bridge strategies have been used: VA-ECMO and then conversion to BHE; BHE and then conversion to VA-ECMO; left VAD and then upgraded to biventricular support (BIVAD); conversion from pulsatile to continuous-flow pumps. RESULTS: A total of 92 patients received MCS with the intent to bridge to OHTx, including 21 (23%) supported with more than one modality. The mean age and weight at support was similar in both groups, but multimodality MCS was used more often in infancy (P = 0.008) and in children less than 10 kg in weight (P = 0.02). The mean duration of support was longer in the multiple MCS group: 40 ± 48 vs 84 ± 43 days (P = 0.0003). Usage of multimodality MCS in dilated cardiomyopathy (19%) and in other diagnoses (29%) was comparable. Incidence of major morbidity (haematological sequelae, cerebrovascular events and sepsis) was similar in both groups. Survival to OHTx/explantation of the device (recovery) and survival to discharge did not differ between single MCS and multiple MCS groups (78 vs 81% and 72 vs 76%, respectively). CONCLUSION: Bridge to OHTx with multiple MCS does not seem to influence the outcome in our population. Infancy and body weight less than 10 kg do not tend to produce higher mortality in the multiple MCS group. However, children receiving more than one modality are supported for longer durations.

Mechanical circulatory support in pediatrics.

There is no reliable published data on the overall prevalence or incidence of heart failure (HF) in children. However, the success of mechanical circulatory support (MCS) in management of HF has raised the prospect of a previously unavailable treatment modality. Orthotopic heart transplant (OHTx) remains the gold standard treatment, but the number of patients requiring this treatment far outweighs the donor availability. It is therefore not surprising to see the popularity of various MCS modalities, with different devices ranging from veno-arterial extra corporeal membrane oxygenation (VA-ECMO) to ventricular assist devices (VADs), which are either para-corporeal or intra-corporeal, with pulsatile or continuous flow. Indication, timing and the choice of the type of mechanical support are crucial so in order to avoid potential lethal complications such as hemorrhage, thrombo-embolism and infections. In the pediatric population, MCS is used mainly as bridge to transplantation but can be used as bridge to recovery in patients with acute myocarditis or following open-heart surgery. Active research is currently underway to develop newer and more durable devices that will assist the pediatric population across all age groups. This research will support different pathologies that have lower incidences of major morbidities, particularly as greater durations of MCS are expected due to a paucity of donors for OHTx. The combined experience developed through the usage of different devices in pediatric and adult populations has led to the to the application of MCS in some subgroups of grown-up congenital heart diseases (CHDs) patients, particularly those with systemic right ventricular failure.

The Ross procedure in patients aged less than 18 years: the midterm results.

OBJECTIVE: This study reviews a single-center experience with the Ross procedure in infants and young children. METHODS: From November 1993 to March 2012, 55 children aged less than 17 years underwent a Ross procedure. The patients ranged in age from 2 days to 17 years (median, 5.9 years). Thirteen patients were infants, and 18 patients were preschool children. The predominant indication for the Ross procedure was aortic stenosis. Twenty-seven patients (49%) with left ventricular outflow tract obstruction underwent a modified Ross-Konno procedure. Twenty-five patients (45%) had undergone 40 previous cardiac procedures. Preoperatively, 3 patients showed severe left ventricular dysfunction, with 2 of the patients requiring intubation and inotropic support. Concomitant procedures were performed in 11 patients (20%). Nine patients underwent mitral valve surgery, and 2 patients underwent subaortic membrane resection. RESULTS: Patients were followed up for a median of 66 months (range, 3 months to 17 years). Overall survival at 1, 2, 5, and 10 years was 84.9%. Hospital mortality rate was 13% (7/55 patients). All deaths occurred in neonates or infants, except 1 who was aged less than 4 years. Freedom from reoperation for autograft failure was 100% at 1 year, 96.7% at 5 years, and 73.7% at 10 years. During follow-up, 7 patients required a reoperation on the autograft for dilatation and severe aortic insufficiency. Freedom from reoperation for the right ventricular outflow tract replacement was 56.1% at 10 years. CONCLUSIONS: The low rate of autograft failure demonstrates that the Ross procedure is an attractive option for the management of aortic valve disease and complex left ventricular outflow tract obstruction in the pediatric population. However, alternative options must be considered in adolescents and young adults.

Managing the posterior coronary loop in the arterial switch operation: the 'inverse flap' technique.

Posterior coronary looping remains a risk factor when performing an arterial switch operation for transposition of the great arteries. In such a situation, to avoid the risk of overstretching, we use an 'inverse' flap technique, resulting in a tension-free relocation.

Ventricular assist device in univentricular heart physiology.

The use of mechanical cardiac assistance is well established as a bridge to orthotopic heart transplantation (OHT) or to recovery for patients with congestive heart failure, however, the experience in single ventricle (SV) physiology is still limited. We report two cases of mechanical assistance in patients with SV physiology: a 2-year old male with hypoplastic left heart syndrome who underwent Norwood Stage I and II followed by HF and a 4-year old female with a univentricular heart who developed a severe right ventricular dysfunction 2 years after a cavopulmonary shunt. Mechanical support utilizing ventricular assist devices (VADs) is considered a valid tool to bridge patients with congestive heart failure to either OHT or to recovery. Increasing experience and improved outcomes utilizing this technology in children with biventricular hearts have led to considering employing these devices in failing SV treatment. We present 2 cases of terminally ill children with SV who were assisted with a VAD.

Managing major vessel injuries with a Fogarty catheter during chest re-opening in children.

Injury of structures, leading to a major bleeding during chest opening, is a severe and potentially life-threatening complication, especially in redo cardiac surgery, both in adults and children. In three paediatric redo operations performed via midline sternotomy, we managed this complication successfully and uneventfully by using an inflated Fogarty catheter to plug the blood leak from the injured vessel before repairing the lesion under direct vision in a bloodless surgical field. Herein we report in detail the technique used and a comment on our experience.

One-stage repair of aberrant left brachiocephalic artery and coarctation of the aorta in right aortic arch.

The combination of right aortic arch with aberrant left brachiocephalic artery and aortic coarctation is very rare. Here, we report the case of a 3.1-kg neonate with multiple malformations who received detailed preoperative anatomical definition by chest computed tomography (CT) scan and eventually underwent one-stage repair at the age of 17 days. The surgical technique included left brachiocephalic artery detachment and its end-to-end anastomosis to the branch of a monofurcated pulmonary homograft used to treat the aortic arch coarctation simultaneously. Postoperative control chest CT scan performed 3 months postoperatively revealed optimal repair. Considerations on imaging and surgical technique are reported.

Plastic bronchitis after extracardiac Fontan operation.

BACKGROUND: We discuss 4 cases of plastic bronchitis (PB) after Fontan procedure observed at our Institution, with the aim to identify an effective treatment and possible factors favoring the onset of PB. Plastic bronchitis is an uncommon disease characterized by recurrent formation of large pale bronchial casts obstructing the tracheobronchial tree. The treatment includes inhaled or systemic steroids, aerosolized mucolytics, bronchoscopic lavage, direct bronchoscopic extraction and, in few reports, aerosolized fibrinolytic and pulmonary vasodilators. METHODS: Four cases of PB after Fontan procedure occurred in our center from January 2008 to January 2012. RESULTS: All patients showed preserved ventricle function and underwent embolization of systemic-pulmonary collaterals prior to a Fontan procedure and all had chylothorax in the perioperative period. Two patients died; 1 of massive thrombosis of the superior vena cava and right pulmonary artery and the other of acute asphyxiation and refractory cardiac failure. CONCLUSIONS: The exact causes of PB in Fontan patients remain unknown. An early diagnosis and a multiple therapy with steroids, mucolytics, pulmonary vasodilators, and aerosolized tissue plasminogen activator may be effective.

Polydioxanone sternal sutures for prevention of sternal dehiscence.

BACKGROUND: Sternal dehiscence and wound instability are troublesome complications following median sternotomy. Classic sternal approximation with stainless steel wires may not be the ideal approach in patients predisposed to these complications. We tested the efficacy of polydioxanone (PDS) suture in sternal closure and in prevention of complications in comparison to steel wires in high-risk individuals. METHODS: Three hundred sixty-six patients undergoing elective cardiac surgery with full median sternotomy and having body surface area (BSA) less than 1.5 m(2) were randomly assigned to receive PDS (n = 181) or stainless steel (SS, n = 185) sternal approximation. The study was focused on aseptic sternal complications, namely bone dehiscence and superficial wound instability. RESULTS: Both bone dehiscence and superficial wound instability were less frequent in the PDS Group (4 and 3 cases in the SS Group, respectively, vs. no cases in the PDS Group). Cox proportional hazards regression model in the whole study population identified female sex, chronic renal insufficiency, diabetes, advanced age, lower sternal thickness, osteoporosis, corticosteroid therapy, and prolonged CPB or ventilation times as predisposing factors to any of the two studied sternal complications. DISCUSSION: Data suggest that PDS suture can protect against development of aseptic sternal complications following median sternotomy in high-risk patients with little body mass. The adoption of PDS in other subsets of patients, i.e., obese individuals, is to be questioned.