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Background: Infants with single ventricle heart disease and severe atrioventricular valve regurgitation have poor outcomes following conventional staged palliation. As such, ventricular assist device (VAD) placement along with hybrid stage 1 palliation has been proposed as a bridge to heart transplant. We present a novel surgical technique for VAD implantation concurrent with hybrid stage 1 that avoids cardiopulmonary bypass. Methods: We performed a retrospective review of our institutional experience with this novel surgical technique. Results: Three patients (weight, 2.7-3.5 kg; age, 3 to 5 days) underwent hybrid stage 1 with VAD placement, consisting of bilateral 3.5-mm expandable polytetrafluoroethylene (PTFE) pulmonary artery bands, a ductal stent, a 6-mm Berlin Heart outflow cannula onto the main pulmonary trunk with a 10-mm graft, a 6-mm Berlin Heart outflow cannula onto the right atrium, and a 10-mL Berlin Heart pump. In patients with severe aortic arch hypoplasia or coarctation, a 4-mm PTFE graft was sewn from the VAD outflow graft to the innominate artery to protect coronary and cerebral perfusion. Procedures were performed off bypass with minimal blood product use. Patients were extubated on postoperative days 2, 2, and 5. There were no procedural complications. All patients were transferred out of the intensive care unit and demonstrated appropriate weight gain. Anticoagulation strategy was bivalirudin and antiplatelet therapy. The patients underwent transplantation after 149 days, 157 days, and 288 days of support. Conclusions: Off-pump single ventricle VAD placement is technically feasible and can be done at the time of hybrid stage 1 palliation with minimal operative morbidity as a bridge to transplant.

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OBJECTIVE: The use of ventricular assist devices (VAD) is increasing; however, diagnosis and management of device complications, such as the driveline exit site (DES) being the portal of entry for fungal infection, is not well known. METHOD: A systematic review involving searching PubMed (2005 to July 2020) was conducted. The case of a 43-year-old female patient who had a left VAD (LVAD) (HeartMate 3, Abbott, US) is also reported. RESULTS: The patient was successfully treated with ketoconazole cream and oral fluconazole for likely superficial DES fungal infections. We included 36 studies that met our inclusion criteria; however, only one was included in our review. In the literature, five cases of DES fungal infection were reported, with Candida being the only fungal pathogen. CONCLUSION: LVAD fungal infections are uncommon but can be responsible for high mortality rates, require a prolonged period of treatment, and can present a huge problem when surgical alternatives are not available. However, Candida species are most common. Fungal infections can only produce clear discharge, and so the classic definition of driveline infection based on purulent secretion can vary. Negative skin culture does not exclude the diagnosis of infection of the DES, and so empirical diagnosis may only be clinically based.

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Objectives: Percutaneous pulmonary artery cannulas, used as inflow for left ventricular venting or as outflow for right ventricular mechanical circulatory support, are easily and rapidly deployable with transesophageal and fluoroscopic guidance. Methods: We chose to review our institutional and technical experience with all right atrium to pulmonary artery cannulations. Results: Based on the review, we describe 6 right atrium to pulmonary artery cannulation strategies. They are divided into total right ventricular assist support, partial right ventricular assist support, and left ventricular venting. A single limb cannula or a dual lumen cannula can be used for right ventricular support. Conclusions: In the right ventricular assist device configuration, percutaneous cannulation may prove beneficial in cases of isolated right ventricular failure. Conversely, pulmonary artery cannulation can be used for left ventricular venting as drainage to a cardiopulmonary bypass or extracorporeal membrane oxygenation circuit. This article can be used as a reference for the technical aspects of cannulation, decision-making in patient selection, and management of patients in these clinical scenarios.

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Antecedentes: Los dispositivos de asistencia ventricular (VAD, sigla en inglés) se utilizan cada vez más para el manejo de la insuficiencia cardíaca descompensada en unidades de cuidados intensivos. El manejo nutricional es fundamental para la evolución clínica de estos pacientes. Objetivos: El objetivo fue evaluar en cuánto tiempo se puede alcanzar las necesidades nutricionales, utilizando distintas modalidades de apoyo nutricional, en pacientes que requirieron asistencia con VAD por insuficiencia cardíaca aguda en una clínica privada del país. Métodos: En una clínica privada se efectuó un estudio observacional retrospectivo analizando los datos clínicos relacionados al aporte nutricional de 12 pacientes que requirieron asistencia con VAD. Las vías de aporte nutricional evaluadas fueron la nutrición enteral (NE) y/o nutrición parenteral (NP). Se midió el tiempo de implementación del apoyo nutricional y su efecto se estimó por una valoración nutricional subjetiva y por la medición de indicadores de laboratorio. Además, se vigilaron las complicaciones asociadas al aporte nutricional. Resultados: El estudio incluyó a 12 pacientes. Los objetivos nutricionales se alcanzaron por completo en el 91% de los pacientes (n=11) en 3,7 ± 1 días después de iniciado el apoyo nutricional. En ese momento, 5 pacientes recibían NE exclusiva, 4 pacientes NP complementaria a la NE, 1 paciente NE complementaria a la alimentación oral y 1 paciente con vía oral. Al momento de alcanzar los requerimientos nutricionales ningún paciente tenía NP exclusiva. Conclusión: Concluimos que el apoyo nutricional precoz es factible y seguro en pacientes con VAD. Alcanzar los objetivos nutricionales es posible sin efectos adversos graves. Se necesitan estudios futuros para determinar el beneficio a largo plazo del apoyo nutricional agresivo para pacientes en estado crítico que requieren apoyo hemodinámico.

Background: Ventricular assist devices (VAD) are being used more frequently in patients with severe heart failure. Nutritional support is a critical factor for the outcome in these patients. Aim: to evaluate the time required and mode of nutritional support in patients with severe cardiac dysfunction being treated with VAD. Methods: 12 patients with VAD being treated in an intensive care unit were evaluated to determine the time and mode of support required to achieve adequate nutrition. Enteral and / or parenteral modes of nutritional support were used. The outcomes were evaluated by subjective appreciation, weight measurement and serum levels of albumin, pre-albumin and vitamin D. Results: Adequate nutritional support was achieved in 91% of patients a mean of 3 days after beginning of treatment (SD 1 day). At that time 5 patients were receiving only enteral nutrition, 4 patients enteral and parenteral nutrition, 1 patient enteral nutrition in addition to oral nutrition and 1 patients was receiving only oral nutrition. No patient was receiving only parenteral nutrition. Conclusion: early nutritional support is posible and safe in patients with an VAD. Further studies are needed to evaluate long term benefits of this strategy of nutritional support.

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Objective: The changing surgical education landscape in surgical training pathways greatly diminished cardiac surgical knowledge, interest, and skills among general surgery trainees. To address this issue, our department developed a cardiac surgery simulation program. Methods: All simulation sessions lasted at least 2 hours and occurred during resident physician protected education time. Participants were postgraduate year 2 through 5 general surgery residents assisted by staff and led by cardiac surgery faculty. Five of the 6 sessions were porcine heart wet labs simulating coronary anastomoses, surgical aortic valve replacement, mitral valve repair and replacement, and left ventricular assist device implantation. The transcatheter aortic valve replacement session was designed as a video simulation and a manikin for wire manipulation and implantation. At the end of each lab, all participants were surveyed about their experiences. Results: An average of 10 resident physicians participated in each session (range, 8-13), for a total of 120 simulation hours. One hundred percent of residents surveyed agreed that the labs improved knowledge and understanding of the disease process, improved understanding of cardiac surgical principles, and helped acquire skills for surgical residency and treatment. Factors that residents cited for increased attendance rate included protected education time, hands-on experience, and a high faculty-to-resident ratio. Conclusions: This program successfully demonstrates that cardiac surgery training and simulation can be integrated into general surgery residency programs, despite the lack of cardiac surgery requirements. Additional metrics for future study includes technical grades on resident physicians' performance to further assess the value of this program.

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BACKGROUND: Mechanical heart valves (MHV) and its fluid dynamics inside a pulsatile pediatric ventricular assist device (PVAD) can be associated with blood degradation. In this article, flow structures are analyzed and compared by an experimental investigation on the effect of bileaflet MHV positioned at varying angles in the inlet port orifice of a PVAD. METHODS: Time-resolved particle image velocimetry was applied to characterize the internal flow of the device. St Jude Medical bileaftlet valves were used on the inlet orifice and positioned at 0°, 15°, 30°, 45°, 60°, and 90° in relation to the centerline of the device. Three planes with bidimensional velocity magnitude fields were considered in the analysis with visualization of diastolic jets, device wall washing patterns and flow circulation during emptying or systole of the pump. Also, the washing vortex area, and vertical velocity probabilities of regurgitant flows in the inlet valve were evaluated. RESULTS: The results show that a variation in the angle of the MHV at the inlet port produced distinct velocities, fluid structures, and regurgitant flow probabilities within the device. MHV positioned at an angle of 0° generated the strongest inlet jet, larger vortex area during filling, more prominent outgoing flow, and less regurgitation compared to the angles studied. The presence of unfavorable fluid structures, such as small vortices, and/or sudden flow structure interruption, and/or regurgitation, were identified at 45° and 90° angles. CONCLUSIONS: The 0° inlet angle had better outcomes than other angles due to its consistency in the multiple parameters analyzed.

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SUMMARY OBJECTIVE: We aimed to investigate whether sarcopenia measured from pectoralis muscles is a risk factor for long-term mortality in left ventricular assist device patients. METHODS: Patients aged >18 years implanted with a left ventricular assist device in a single center between 2013 and 2019 were retrospectively included. Patients without a thoracic computed tomography scan performed within 3 months of left ventricular assist device implantation and without computed tomography scans appropriate for pectoralis muscle measurement were excluded. Pectoralis muscle measurements were made on thoracic computed tomography slices, and pectoralis muscle indices were calculated for each patient. Sarcopenia was defined as being in the gender-specific lowest tertile of pectoralis muscle index. Survival was compared between patients with and without sarcopenia. RESULTS: The study was conducted on 64 left ventricular assist device patients who met the inclusion criteria. Notably, 21 (32.8%) of the study patients were sarcopenic. Diabetes mellitus and sarcopenia were more common in patients with 2-year mortality in our cohort. Patients with sarcopenia had a worse 2-year survival (p<0.001). Sarcopenia had an adjusted hazard ratio of 4.04 (95% confidence interval (CI) 1.36-12.02, p=0.012), while diabetes mellitus was associated with an adjusted hazard ratio of 3.14 (95%CI 1.17-8.39, p=0.023). CONCLUSION: Sarcopenia defined by low pectoralis muscle index increases the risk for 2-year mortality in left ventricular assist device patients.

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Objective: Patients with profound cardiogenic shock may require venoarterial (VA) extracorporeal membrane oxygenation (ECMO) for circulatory support most commonly via the femoral vessels. The rate of cardiac recovery in this population remains low, possibly because peripheral VA-ECMO increases ventricular afterload. Whether direct ventricular unloading in peripheral VA-ECMO enhances cardiac recovery is unknown, but is being more frequently utilized. A randomized trial is warranted to evaluate the clinical effectiveness of percutaneous left ventricle venting to enhance cardiac recovery in the setting of VA-ECMO. Methods: We describe the rationale, design, and initial testing of a randomized controlled trial of VA-ECMO with and without percutaneous left ventricle venting using a percutaneous micro-axial ventricular assist device. Results: This is an ongoing prospective randomized controlled trial in adult patients with primary cardiac failure presenting in cardiogenic shock requiring peripheral VA-ECMO, designed to test the safety and effectiveness of percutaneous left ventricle venting in improving the rate of cardiac recovery. Conclusions: The results of this nonindustry-sponsored trial will provide critical information on whether left ventricle unloading in peripheral VA-ECMO is safe and effective.

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The highlights in cardiothoracic transplantation focus on the recent research pertaining to heart and lung transplantation, including expansion of the donor pool, the optimization of donors and recipients, the use of mechanical support, the perioperative and long-term outcomes in these patient populations, and the use of transthoracic echocardiography to diagnose rejection.

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According to the World Health Organization, cardiovascular disease is the number one cause of death worldwide, except Africa, where Acquired Immune Deficiency Syndrome is the leading cause of death. In this scenario, the ventricular assist device (VAD) remains the unique alternative to extend patient life until heart transplantation. At Dante Pazzanese Institute of Cardiology, the research and development of an axial flow VAD to be fully implantable within the heart was started. This pump, denominated Transventricular Assist Device (TVAD), can be surgically implanted through a small left intercostal incision in a minimally invasive manner. The goal of this work is to analyze the impeller geometries of the TVAD, to avoid high shear stresses in the fluid and aim for the best conditions to support the circulatory system using computational fluid dynamics and in vitro tests. Different rotor geometries were selected according to the literature; based on the results, the best rotor was elected. This rotor contains a pair of spiral blades of constant and relatively high pitch, which pumps liquid at a flow rate of 3 L/min at 73 mm Hg. It is also expected that this rotor presents a moderate hemolysis since the shear rate is acceptable.

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This study presents an assessment for long-term use of the apical aortic blood pump (AABP), focusing on wear reduction in the bearing system. AABP is a centrifugal left ventricle assist device initially developed for bridge to transplant application. To analyze AABP performance in long-term applications, a durability test was performed. This test indicated that wear in the lower bearing pivot causes device failure in long-term. A wear test in the bearing system was conducted to demonstrate the correlation of the load in the bearing system with wear. Results from the wear test showed a direct correlation between load and wear at the lower bearing pivot. In order to reduce load, thus reducing wear, a new stator topology has been proposed. In this topology, a radial stator would replace the axial stator previously used. Another durability test with the new stator has accounted twice the time without failure when compared with the original model.

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Congestive heart failure is a pathology of global incidence that affects millions of people worldwide. When the heart weakens and fails to pump blood at physiological rates commensurate with the requirements of tissues, two main alternatives are cardiac transplant and ventricular assist devices (VADs). This article presents the design strategy for development of a customized VAD electromagnetic actuator. Electromagnetic actuator is a brushless direct current motor customized to drive the pump impeller by permanent magnets located in rotor-stator coupling. In this case, ceramic pivot bearings support the VAD impeller. Electronic circuitry controls rotation switching current in stator coils. The proposed methodology consisted of analytical numerical design, tridimensional computational modeling, numerical simulations using Maxwell software, actuator prototyping, and validation in the dynamometer. The axial flow actuator was chosen by its size and high power density compared to the radial flow type. First step consisted of estimating the required torque to drive the pump. Torque was estimated at 2100 rpm and mean current of 0.5 A. Numerical analysis using finite element method mapped vectors and fields to build stator coils and actuator assemblage. After tests in the dynamometer, experimental results were compared with numerical simulation and validated the proposed model. In conclusion, the proposed methodology for designing of VAD electromechanical actuator was considered satisfactory in terms of data consistency, feasibility, and reliability.

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OBJECTIVES: To determine the presence of and periprocedural changes caused by aortic regurgitation (AR) in patients supported with an Impella (Abiomed, Danvers, MA) left ventricular assist device. DESIGN: Retrospective. SETTING: Tertiary academic medical center. PARTICIPANTS: Patients who underwent insertion of an Impella device at Allegheny General Hospital from January 2015 to December 2018. INTERVENTIONS: Analysis of patient electronic medical records. MEASUREMENTS AND MAIN RESULTS: Demographic information; comorbidities; duration of support; and the presence and severity of AR pre-procedure and post-procedure, as reported by echocardiography, were analyzed. The electronic medical records of 69 patients were included in the present study. Before placement of the Impella device, 25 (35%) patients showed detectable AR, with 18 (26%) showing mild AR and 7 (10%) showing moderate AR. After the removal of the Impella device, AR remained steady or increased in 61 patients. Fifteen patients (22%) demonstrated mild AR, 6 (8.7%) demonstrated moderate AR, and 2 (2.9%) demonstrated severe AR. An increase in severity of AR was noted in 9 patients (14.7%), and 52 patients (85%) had no change in the severity of AR. The duration of support with the Impella device, demographic variables, and comorbidities were not associated with a statistically significant risk for increased severity of post-procedural AR in multiple multivariable logistic regression analyses. CONCLUSIONS: The presented data suggest that after Impella device support, a significant proportion of patients may show evidence of increased AR. Additional studies are needed to understand the etiology and significance of this observation.

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Introducción. El objetivo del presente estudio fue analizar el empleo preoperatorio de azul de metileno (AM) como prevención del desarrollo de síndrome vasopléjico en pacientes bajo implante de dispositivos de asistencia ventricular izquierda (DAVI), considerando: porcentaje de pacientes que desarrollan vasoplejía, requerimiento de vasopresores, morbimortalidad postoperatoria y seguridad del empleo del fármaco. Métodos. Fueron incluidos pacientes sometidos al implante de DAVI de flujo continuo (HeartMate II o HeartWare) entre enero de 2009 y enero de 2014. Los pacientes fueron aleatorizados a AM en dosis de 1,5 mg/Kg, previamente a la circulación extracorpórea, seguido por una infusión de 0,5 mg/Kg/hora del mismo. Se definió síndrome vasopléjico en base a hipotensión arterial con presión capilar pulmonar baja, índice cardíaco normal o elevado, resistencias sistémicas descendidas y requerimiento vasopresor. Un valor de P<0,05 se consideró significativo. Resultados. En el lapso del estudio fueron incluidos 64 pacientes, 33 de los cuales recibieron AM (dosis promedio 3,5 mg/kg) y 31 pacientes representaron el grupo control. Veinte (31,1%) pacientes desarrollaron vasoplejía, 6 (18,2%) pacientes en el grupo AM frente a 14 (45,2%) del grupo control (P=0,01; OR 0,27 con IC de 0,08-0,84). El requerimiento de vasopresores resulto, asimismo, inferior en los pretratados, 23 (69,7%) pacientes versus 30 (96,8%) pacientes (P=0,004; OR 0,07; IC 0,003-0,522). La mortalidad postoperatoria resulto de 13 (20,3%) pacientes, 4 (12,1%) de ellos en el grupo AM frente a 9 (29%) del grupo control (P=0,06; OR 0,35; IC 0,106-1,117). En todos los pacientes tratados con AM se evidenció el cambio de coloración de la orina. Cinco (7,8%) pacientes presentaron hipertensión arterial, requiriendo vasodilatadores endovenosos, 3 (9,1%) pacientes en el grupo AM frente a 2 (6,4%) en el grupo control (valor de P=0,3). Conclusiones. El empleo preoperatorio de AM se asoció con la reducción del desarrollo de síndrome vasopléjico, así como del requerimiento vasopresor. Se observó una reducción de complicaciones postoperatorias y una tendencia a menor mortalidad. Un número mayor de pacientes requiere ser valorado para comprobar la utilidad de esta estrategia

Introduction. The objective of this study was to analyze preoperative utilization of methylene blue (MB) for preventing development of vasoplegic syndrome in patients underwent left ventricle assist device (LVAD) implant considering: percentage of patients developing vasoplegia, vasopresor requirement, perioperative morbidity and mortality and safety associated with MB s use. Methods. There were admitted patients underwent an implant of a LVAD of continuous flow (HeartMate II or HeartWare) from January 2009 to January 2014. Patients were randomized to MB, 1.5 mg/Kg one hour before extracorporeal circulation followed for 0.5 mg/kg/hour or placebo (control group). It was defined vasoplegia by: arterial hypotension, low capillary pulmonary pressure, normal or elevated cardiac index, descended systemic vascular resistances and vasopresor requirement. A P<0.05 was considered significant. Results. There were included 64 patients, 33 of them were randomized to MB (average dose 3.5 mg/Kg) and 31 patients represented control group. Twenty (31.1%) patients developed vasoplegia, 6 (18.2%) patients from MB s group versus 14 (45.2%) patients from control group (P=0.01, OR 0.27, IC de 0.08-0.84). Vasopressor requirement was lower in those receiving MB 23 (69.7%) patients versus 30 (96.8%) patients (P=0.004, OR 0.07, IC 0.003- 0.522). Postoperative mortality was 13 (20.3%) patients, 4 (12.1%) of them receiving MB versus 9 (29%) patients from control group (P=0.06, OR 0.35 IC 0.106-1.117). In all treated patients it was evident a change in urine s color and also five (7.8%) patients developed arterial hypertension, requiring vasodilators 3 (9.1%) patients from MB s group versus 2 (6.4%) from control (valor de P=0.3). Conclusions. The preoperative use of MB was associated with reduction of vasoplegia and a lower vasopresor requirements. It was also observed reduction of postoperative complications and a trend to reduced mortality. A superior number of patients needs to be evaluated for proving the value of this strategy

Introdução. O objetivo deste estudo foi analisar a utilização pré-operatória do azul de metileno (AM) para prevenir o desenvolvimento da síndrome vasoplégica em pacientes submetidos a implante de dispositivo de assistência ventricular esquerda (DAVE), considerando: porcentagem de pacientes em desenvolvimento de vasoplegia, necessidade de vasopresor, morbidade e mortalidade e segurança perioperatórias associado ao uso do AM. Métodos. Foram admitidos pacientes submetidos a um implante de uma DAVE de fluxo contínuo (HeartMate II ou HeartWare) de janeiro de 2009 a janeiro de 2014. Os pacientes foram randomizados para AM, 1,5 mg/kg uma hora antes da circulação extracorpórea, seguidos por 0,5 mg/kg/hora ou placebo (grupo controle). Foi definida vasoplegia por: hipotensão arterial, pressão pulmonar capilar baixa, índice cardíaco normal ou elevado, resistências vasculares sistêmicas descendentes e necessidade de vasopresor. Um P<0,05 foi considerado significativo. Resultados. Foram incluídos 64 pacientes, 33 deles foram randomizados para MB (dose média de 3,5 mg / kg) e 31 pacientes representaram o grupo controle. Vinte (31,1%) pacientes desenvolveram vasoplegia, 6 (18,2%) pacientes do grupo AM versus 14 (45,2%) pacientes do grupo controle (P=0,01; OR 0,27; IC de 0,08-0,84). A necessidade de vasopressores foi menor nos pacientes que receberam AM 23 (69,7%) versus 30 (96,8%) pacientes (P=0,004; OR 0,07; IC 0,003-0,522). A mortalidade pós-operatória foi de 13 (20,3%) pacientes, 4 (12,1%) deles recebendo AM versus 9 (29%) pacientes do grupo controle (P=0,06; OR 0,35; IC 0,106-1,117). Em todos os pacientes tratados, foi evidente uma alteração na cor da urina e também cinco (7,8%) pacientes desenvolveram hipertensão arterial, exigindo vasodilatadores 3 (9,1%) pacientes do grupo AM versus 2 (6,4%) do controle (valor de P=0,3). Conclusões. O uso pré-operatório de AM foi associado à redução da vasoplegia e menor necessidade de vasopresor. Também foi observada redução das complicações pós-operatórias e tendência à redução da mortalidade. Um número superior de pacientes precisa ser avaliado para provar o valor dessa estratégia

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