Hemofiltration Improves Blood Perfusate Conditions Leading to Improved Ex Situ Heart Perfusion.

The aim was to optimize the perfusate composition by including a hemofiltrator to the PhysioHeartplatform for ex situ heart perfusion of porcine slaughterhouse hearts. Fourteen hearts were harvested from Dutch Landrace pigs and slaughtered for human consumption. All hearts were preserved for 4 hours using static cold storage before reperfusion for 4 hours on the PhysioHeart platform. Seven hearts were assigned to the hemofiltration group, where a hemofiltrator was added to the perfusion circuit, while the control group did not receive hemofiltration. In the hemofiltration group, the perfusion fluid was filtrated for 1 hour with a flow of 1 L/hour before reperfusion. After mounting the heart, hemofiltration was maintained at 1 L/hour, and cardiac function and blood samples were analyzed at multiple time points. Preserved cardiac function was defined as a cardiac output >3.0 L/min with a mean aortic pressure >60 mm Hg and a left atrial pressure <15 mm Hg. Hemofiltration resulted in a significantly reduced potassium concentration at all time points ( p < 0.001), while sodium levels remained at baseline values ( p < 0.004). Furthermore, creatinine and ammonia levels decreased over time. Functional assessment demonstrated a reduced left atrial pressure ( p < 0.04) and a reduction of the required dobutamine dose to support myocardial function ( p < 0.003) in the hemofiltration group. Preserved cardiac function did not differ between groups. Hemofiltration results in an improved biochemical composition of the whole blood perfusate and preserves cardiac function better during normothermic perfusion based on a reduced left atrial pressure (LAP) and dobutamine requirement to support function.

Gene therapy during ex situ heart perfusion: a new frontier in cardiac regenerative medicine?

Ex situ organ preservation by machine perfusion can improve preservation of organs for transplantation. Furthermore, machine perfusion opens up the possibilities for selective immunomodulation, creation of tolerance to ischemia-reperfusion injury and/or correction of a pathogenic genetic defect. The application of gene modifying therapies to treat heart diseases caused by pathogenic mutations during ex situ heart perfusion seems promising, especially given the limitations related to delivery of vectors that were encountered during clinical trials using in vivo cardiac gene therapy. By isolating the heart in a metabolically and immunologically favorable environment and preventing off-target effects and dilution, it is possible to directly control factors that enhance the success rate of cardiac gene therapy. A literature search of PubMed and Embase databases was performed to identify all relevant studies regarding gene therapy during ex situ heart perfusion, aiming to highlight important lessons learned and discuss future clinical prospects of this promising approach.

Successful aortic arch cannulation and perfusion of a heart donated after circulatory death: A case report.

INTRODUCTION: We describe successful aortic arch cannulation and perfusion of a heart donated after circulatory death using the Transmedics Organ Care System™. CASE REPORT: A 47-year old man developed advanced heart failure symptoms after prior mustard operation for transposition of the great arteries. He matched a DCD-donor and required an elongated aorta for implantation due to his altered anatomy. The donor heart was retrieved and successfully perfused via aortic arch cannulation for 4.5 h with satisfactory perfusion parameters. DISUSSION: Although Transmedics advises against aortic arch cannulation due to concerns regarding malperfusion, satisfactory and safe perfusion can be achieved by careful positioning of the heart. Awareness and attention to the occurrence of malperfusion is mandatory, especially during transport, to achieve satisfactory outcome. CONCLUSION: Aortic arch cannulation is feasible without compromising quality of perfusion. This is relevant for patient that require an elongated aorta after surgically corrected congenital heart disease.

Mixed Reality in Modern Surgical and Interventional Practice: Narrative Review of the Literature.

BACKGROUND: Mixed reality (MR) and its potential applications have gained increasing interest within the medical community over the recent years. The ability to integrate virtual objects into a real-world environment within a single video-see-through display is a topic that sparks imagination. Given these characteristics, MR could facilitate preoperative and preinterventional planning, provide intraoperative and intrainterventional guidance, and aid in education and training, thereby improving the skills and merits of surgeons and residents alike. OBJECTIVE: In this narrative review, we provide a broad overview of the different applications of MR within the entire spectrum of surgical and interventional practice and elucidate on potential future directions. METHODS: A targeted literature search within the PubMed, Embase, and Cochrane databases was performed regarding the application of MR within surgical and interventional practice. Studies were included if they met the criteria for technological readiness level 5, and as such, had to be validated in a relevant environment. RESULTS: A total of 57 studies were included and divided into studies regarding preoperative and interventional planning, intraoperative and interventional guidance, as well as training and education. CONCLUSIONS: The overall experience with MR is positive. The main benefits of MR seem to be related to improved efficiency. Limitations primarily seem to be related to constraints associated with head-mounted display. Future directions should be aimed at improving head-mounted display technology as well as incorporation of MR within surgical microscopes, robots, and design of trials to prove superiority.

[Heart donation after circulatory death: ethical and emotional aspect of central normothermic regional perfusion]. / Hoe behoud je een donorhart na circulatoir overlijden?

Heart transplantation after circulatory death is possible in different countries with the use of ex situ normothermic perfusion of the donor heart. Central normothermic regional perfusion, where the circulation in the donor is restarted using an extracorporeal life support system after circulatory death, may give a better 1-years survival and a reduction in costs compared to ex situ normothermic perfusion of the donor heart. However, restarting circulation in a donor that was just declared death by circulatory criteria may be controversial. The advantages described are, in our view, reason to consider central normothermic regional perfusion, in which case a debate on ethical and emotional aspects is of great importance. In this article, we describe two point of views and hope in this way to start the debate on central normothermic regional perfusion in the Netherlands.

Application of three-dimensional computed tomography imaging and reconstructive techniques in lung surgery: A mini-review.

Background: Pulmonary surgery is an innovative discipline with increasing demands for minimally invasive techniques in complicated anatomical resections, warranting adequate preoperative imaging of relevant surgical anatomy to ensure safe and radical resection of target lesions. Over the recent years, the emergence of imaging techniques enabling three-dimensional reconstruction has exerted promising influence on pulmonary surgery, facilitating optimal surgical planning and easier identification of the spatial relationship between bronchovascular structures in the individual patient and aiding the safe resection of target pulmonary lesions. The goal of this mini-review is to provide an overview of three-dimensional computed tomography imaging within pulmonary surgery. Methods: The authors performed a targeted qualitative review of the literature to identify current trends and to provide better understanding of three-dimensional reconstruction within the boundaries of pulmonary surgery. Results: Three-dimensional reconstructive techniques can be used for resectability assessment, identification of surgically relevant interindividual anatomic variance and may improve perioperative outcomes. Discussion: Three-dimensional reconstruction using computed tomography imaging improves surgical planning and there is evidence that it results in shorter operative times, less intraoperative blood loss and lower rates of surgical conversion, as it can be applied both pre- and intraoperatively.

Review of case reports on hyperkalemia induced by dietary intake: not restricted to chronic kidney disease patients.

Hyperkalemia is a metabolic disturbance of the potassium balance that can cause potentially fatal cardiac arrhythmias. Kidney dysfunction and renin-angiotensin-aldosterone system inhibiting drugs are notorious for their tendency to induce hyperkalemia by decreasing the excretion of potassium. The role of dietary potassium intake in inducing hyperkalemia is less clear. We review and analyze the common presentation, laboratory, and electrocardiogram (ECG) findings and therapeutic options associated with dietary-induced hyperkalemia, and find evidence for hyperkalemia development in non-renal impaired patients. Thirty-five case reports including 44 incidences of oral intake-induced hyperkalemia were assessed, 17 patients did not suffer from kidney dysfunction. Mean age was 49 ± 20 years. Mean potassium concentration was 8.2 ± 1.4 mEq/l, most frequently caused by abundant intake of fruit and vegetables (n = 17) or salt substitutes (n = 12). In patients with normal kidney function, intake of salt substitutes or supplements was the main cause of hyperkalemia. Main symptoms encompassed muscle weakness (29.5%), vomiting (20.4%), and dyspnea (15.9%). When ECGs were performed (n = 30), abnormalities were present in 86.7% of cases. Treatment involved administration of insulin (n = 22), sodium/calcium polystyrene sulfonate (n = 14), and/or calcium gluconate (n = 14). Forty patients fully recovered. Three, non-renal impaired, patients passed away. These results offer insight into the clinical aspects of dietary-induced hyperkalemia and suggest that the common assumption that dietary-induced hyperkalemia is a condition of renal impaired patients might be incorrect.

Therapy and Outcome of Staphylococcus aureus Infections of Intracorporeal Ventricular Assist Devices.

Infection of the driveline or pump pocket is a common complication in patients with ventricular assist devices (VADs) and Staphylococcus aureus is the main pathogen causing such infections. Limited evidence is currently available to guide the choice of antibiotic therapy and the duration of treatment in these patients. Patients at the University Medical Center Utrecht who developed a VAD-related S. aureus infection between 2007 and 2016 were retrospectively assessed. Blood culture isolates were typed by whole genome sequencing to differentiate between relapses and reinfections, and to determine whether antibiotic therapy had led to acquisition of resistance mutations. Twenty-eight patients had S. aureus VAD infections. Ten of these patients also suffered S. aureus bacteremia. Discontinuation of antibiotic therapy was followed by relapse in 50% of the patients without prior S. aureus bacteremia and in 80% of patients with bacteremia. Oral cephalexin could ultimately suppress the infection for the duration of follow-up in 8/8 patients without S. aureus bacteremia and in 3/6 patients with S. aureus bacteremia. Clindamycin failed as suppressive therapy in 4/4 patients. Cephalexin appears an adequate choice for antibiotic suppression of VAD infections with methicillin-susceptible S. aureus. In patients without systemic symptoms, it may be justified to attempt to stop therapy after treatment of the acute infection, but antibiotic suppression until heart transplant seems indicated in patients with S. aureus bacteremia.