AIMS: This study aimed to compare the changes in the left ventricle (LV) and right ventricle (RV) geometry and performance after the implantation of HeartMate II (HMII) and HeartMate 3 (HM3). In addition, we investigated whether the echocardiographic parameters LV sphericity index (LVSI) and the novel pressure-dimension index (PDI) can predict post-operative right ventricular failure (RVF). METHODS AND RESULTS: Between 2012 and 2020, 46 patients [HMII (n = 22) and HM3 (n = 24)] met the study's criteria and had echocardiography tests pre-operatively, 6 and 12 months post-operatively. The LVSI and PDI were calculated together with the standard LV and RV echocardiographic parameters. The mean follow-up was 24 ± 7 months. In both groups, the LV end-diastolic diameter (LVEDD) significantly decreased 12 months post-operatively compared with the pre-operative values (HMII: 6.4 ± 1.4 cm vs. 5.7 ± 0.9 cm, P = 0.040; HM3: 6.7 ± 1.3 cm vs. 5.5 ± 0.9 cm, P < 0.01, respectively). RV function 12 months post-operatively was better in the HM3 group than in the HMII group, as indicated by a significantly higher RV fractional area change (RVFAC) in the HM3 group than in the HMII group 12 months post-operatively (35 ± 12% vs. 26 ± 16%, P = 0.039), significantly higher tricuspid annular plane systolic excursion (TAPSE) in the HM3 group 12 months post-operatively compared with the HMII group (13.9 ± 1.9 mm vs. 12.0 ± 2.1 mm, P = 0.002), and the tissue Doppler estimated tricuspid annular systolic velocity (TASV) was also significantly higher in the HM3 group 12 months post-operatively compared with the HMII group (11.5 ± 2.7 mm/s vs. 9.9 ± 1.5 mm/s, P = 0.020). The LVSI value was significantly higher 12 months post-operatively in the HMII group than in the HM3 group (1.2 ± 0.4 vs. 0.8 ± 0.2, P = 0.001, respectively), indicating worse geometric changes. The PDI decreased 12 months post-operatively in the HM3-group compared with the baseline (3.4 ± 1.4 mmHg/cm2 vs. 2.0 ± 0.8 mmHg/cm2, P < 0.001). In the univariate and multivariate analyses, only the pre-operative PDI was a predictor of post-operative RVF [odds ratio: 3.84 (95% CI: 1.53-18.16, P = 0.022)]. The area under the curve for pre-operative PDI was 0.912. The 2 year survival was significantly better in the HM3 group (log-rank, P = 0.042). CONCLUSIONS: The design of HM3 offered better geometrical preservation of the LV and enabled normal PDI values, leading to improved RV function, as indicated by better RVFAC, TAPSE, and TASV values. The use of pre-operative PDI as an additional tool for established risk scores might offer a better pre-operative predictor of RVF.
BACKGROUND: Stroke after durable left ventricular assist device (d-LVAD) implantation portends high mortality. The incidence of ischemic and hemorrhagic stroke and the impact on stroke outcomes of temporary mechanical circulatory support (tMCS) management among patients requiring bridge to d-LVAD with micro-axial flow-pump (mAFP, Abiomed) is unsettled. METHODS: Consecutive patients, who underwent d-LVAD implantation after being bridged with mAFP at 19 institutions, were retrospectively included. The incidence of early ischemic and hemorrhagic stroke after d-LVAD implantation (<60 days) and association of pre-d-LVAD characteristics and peri-procedural management with a specific focus on tMCS strategies were studied. RESULTS: Among 341 patients, who underwent d-LVAD implantation after mAFP implantation (male gender 83.6%, age 58 [48-65] years, mAFP 5.0/5.5 72.4%), the early ischemic stroke incidence was 10.8% and early hemorrhagic stroke 2.9%. The tMCS characteristics (type of mAFP device and access, support duration, upgrade from intra-aortic balloon pump, ECMELLA, ECMELLA at d-LVAD implantation, hemolysis, and bleeding) were not associated with ischemic stroke after d-LVAD implant. Conversely, the device model (mAFP 2.5/CP vs. mAFP 5.0/5.5: HR 5.6, 95%CI 1.4-22.7, p = 0.015), hemolysis on mAFP support (HR 10.5, 95% CI 1.3-85.3, p = 0.028) and ECMELLA at d-LVAD implantation (HR 5.0, 95% CI 1.4-18.7, p = 0.016) were associated with increased risk of hemorrhagic stroke after d-LVAD implantation. Both early ischemic (HR 2.7, 95% CI 1.9-4.5, p < 0.001) and hemorrhagic (HR 3.43, 95% CI 1.49-7.88, p = 0.004) stroke were associated with increased 1-year mortality. CONCLUSIONS: Among patients undergoing d-LVAD implantation following mAFP support, tMCS characteristics do not impact ischemic stroke occurrence, while several factors are associated with hemorrhagic stroke suggesting a proactive treatment target to reduce this complication.
It is believed that a lower temperature setting of hypothermic circulatory arrest (HCA) in thoracic aortic surgery causes coagulopathy, resulting in excessive bleeding. However, experimental studies that eliminate clinical factors are lacking. The objective of this study is to investigate the influence of the temperature setting of HCA on coagulation in a pig model. Ten pigs were divided into the following two groups: moderate temperature at 28 °C (group M, n = 5) or lower temperature at 20 °C (group L, n = 5). Two hours of HCA during a total of 4 h of cardiopulmonary bypass (CPB) were performed. Blood samples were obtained at the beginning (T1) and the end (T2) of the surgery, and coagulation capability was analyzed through standard laboratory tests (SLTs) and rotational thromboelastometry (ROTEM). In SLTs, hemoglobin, fibrinogen, platelet count, prothrombin time, and activated partial thromboplastin time were analyzed. In ROTEM analyses, clotting time and clot formation time of EXTEM, maximum clot firmness (MCF), and maximum clot elasticity (MCE) of EXTEM and FIBTEM were analyzed. Fibrinogen decreased significantly in both groups (group M, p = 0.008; group L, p = 0.0175) at T2, and FIBTEM MCF and MCE also decreased at T2. There were no differences regarding changes in parameters of SLTs and ROTEM between groups. CPB decreases coagulation capacity, contributed by fibrinogen. However, a lower temperature setting of HCA at 20 °C for 2 h did not significantly affect coagulopathy compared to that of HCA at 28 °C after re-warming to 37 °C.
BACKGROUND: Acute aortic dissection type A (AADA) is a surgical emergency with relevant mortality and morbidity despite improvements in current management protocols. Identifying patients at risk of a fatal outcome and controlling the factors associated with mortality remain of paramount importance. METHODS: In this retrospective observational study, we reviewed the medical records of 117 patients with AADA, who were referred to our centre and operated on between 2005 and 2021. Preoperative, intraoperative, and postoperative variables were analysed and tested for their correlation with in-hospital mortality. RESULTS: The overall survival rate was 83%. Preoperatively, factors associated with mortality were age (p = 0.02), chronic hypertension (p = 0.02), any grade of aortic valve stenosis in the patient's medical history (p = 0.03), atrial fibrillation (p = 0.04), and oral anticoagulation (p = 0.04). Non-survivors had significantly longer operative times (p = 0.002). During the postoperative phase, mortality was strongly associated with acute kidney injury (AKI) (p < 0.001), acute heart failure (p < 0.001), stroke (p = 0.02), focal neurological deficits (p = 0.02), and sepsis (p = 0.001). In the multivariate regression analysis, the onset of postoperative focal neurological deficits was the best predictor of a fatal outcome after adjusting for ARDS (odds ratio: 5.8, 95%-CI: 1.2-41.7, p = 0.04). CONCLUSIONS: In this retrospective analysis, atrial fibrillation, oral anticoagulation, hypertension, and age were significantly correlated with mortality. Postoperatively, acute kidney injury, acute heart failure, sepsis, and focal neurological deficits were correlated with in-hospital mortality, and focal neurological deficit has been identified as a significant predictor of fatal outcomes. Early detection and interdisciplinary management of at-risk patients remain crucial throughout the postoperative phase.
BACKGROUND: Left ventricular assist devices (LVAD) are an established treatment for end-stage left ventricular heart failure. Parameters are needed to identify the most appropriate patients for LVADs. This study aimed to evaluate pectoral muscle mass and density as prognostic parameters. METHODS: This single-center study included all patients with LVAD implantation between January 2010 and October 2017 and a preoperative chest CT scan. Pectoral muscle mass was assessed using the Pectoralis Muscle Index (PMI, surface area indexed to height, cm2/m2) and pectoral muscle density by Hounsfield Units (HU). Overall mortality was analyzed with Kaplan-Meier survival analysis and 1-year and 3-year mortality with receiver operating characteristic (ROC) curves and Cox regression models. RESULTS: 57 patients (89.5% male, mean age 57.8 years) were included. 64.9% of patients had end-stage left ventricular failure due to ischemic heart disease and 35.1% due to dilated cardiomyopathy. 49.2% of patients had preoperative INTERMACS profile of 1 or 2 and 33.3% received mechanical circulatory support prior to LVAD implantation. Total mean PMI was 4.7 cm2/m2 (± 1.6), overall HU of the major pectoral muscle was 39.0 (± 14.9) and of the minor pectoral muscle 37.1 (± 16.6). Mean follow-up was 2.8 years (± 0.2). Mortality rates were 37.5% at 1 year and 48.0% at 3 years. Neither PMI nor HU were significantly associated with overall mortality at 1-year or 3-year. CONCLUSIONS: The results of our study do not confirm the association between higher pectoral muscle mass and better survival after LVAD implantation previously described in the literature.
Heart Failure , Heart-Assist Devices , Humans , Male , Middle Aged , Female , Pectoralis Muscles , Prognosis , Treatment Outcome , Retrospective Studies , Heart Failure/surgery
A heart transplant is the gold standard therapy for patients with end-stage heart failure. In this case report, situs inversus totalis and congenitally corrected transposition of the great arteries led to a unique and complex preoperative setting. Extended donor organ harvesting, donor graft rotation of 45° to the right and post-operative stenting of the superior vena cava were essential steps in the interdisciplinary management of this case. The patient was transferred to the intensive care unit with moderate inotropic support. He was discharged to rehabilitation on postoperative day 89 and eventually underwent an additional renal transplant 14 months after the cardiac transplant.
Heart Transplantation , Situs Inversus , Transposition of Great Vessels , Male , Humans , Congenitally Corrected Transposition of the Great Arteries , Transposition of Great Vessels/surgery , Situs Inversus/complications , Situs Inversus/surgery , Vena Cava, Superior
PURPOSE: This study aimed to elucidate the strategy of an effective Impella support for better clinical outcomes in patients with a postcardiotomy cardiogenic shock (PCCS). METHODS: This single-center retrospective observational study enrolled 31 patients with PCCS undergoing an elective open-heart surgery followed by Impella support between November 2018 and February 2022 for further analysis. RESULTS: The preoperative Euroscore II and left ventricular (LV) ejection fraction were 9.1 ± 10.4 and 35.7% ± 12.6%, respectively. The in-hospital mortality rate was 51.6% (n = 16). In survivors (n = 15), the mean Impella support time was 6.9 ± 3.5 days. Patients were discharged on the postoperative day 24.9 ± 16.4. Regarding LV remodeling, LV end-diastolic diameter was significantly decreased after Impella support (59.2 ± 6.0 mm vs. 54.4 ± 4.7 mm, p = 0.01, preoperative vs. postoperative). In-hospital mortality rates were comparable with small (CP, n = 6) or large (5.0, n = 25) Impella systems (33.3% [n = 2] vs. 56.0% [n = 14], p = 0.39). However, a lower in-hospital mortality rate was observed in the group with early initiation (i.e., intraoperative) of Impella support (n = 14) than that with delayed Impella initiation (i.e., in the postoperative course) (n = 11) (28.6% [n = 4] vs. 90.9% [n = 10], p = 0.004). CONCLUSIONS: Impella support contributes to LV remodeling in PCCS patients. In-hospital mortality was comparable in different Impella sizes and lower in early Impella initiation.
Cardiac Surgical Procedures , Heart-Assist Devices , Humans , Shock, Cardiogenic/diagnosis , Shock, Cardiogenic/etiology , Shock, Cardiogenic/therapy , Treatment Outcome , Heart-Assist Devices/adverse effects , Retrospective Studies , Cardiac Surgical Procedures/adverse effects
AIMS: The extent of mitral regurgitation (MR) may vary depending on the haemodynamic situation; thus, exercise testing plays an important role in assessing the haemodynamic relevance of MR. We aim to assess prevalence, mechanisms, and prognostic impact of exercise-induced changes in MR in patients with degenerative MR (DegMR) and functional MR (FMR). METHODS AND RESULTS: We enrolled 367 patients with at least mild MR who underwent standardized echocardiography at rest and during handgrip exercise. Handgrip exercise led to an increase in MR by one grade or more in 19% of DegMR and 28% of FMR patients. In FMR, patients with exercise-induced increases in MR, handgrip exercise led to a reduction in left ventricular stroke volume index, being maintained in DegMR patients. Exercise-induced changes in systolic pulmonary artery pressure were linked to changes in effective regurgitant orifice area (DegMR: r = 0.456; P < 0.001; FMR: r = 0.326; P < 0.001). Thus, 26% of patients with DegMR and FMR developed pulmonary hypertension during exercise. In both cohorts, a significant proportion of patients with non-severe MR at rest and exercise-induced severe MR underwent mitral valve surgery/intervention during follow-up. In FMR patients (but not in DegMR patients), early mitral valve surgery/intervention was independently associated with lower event rates during follow-up [0.177 (0.027-0.643); P = 0.025]. CONCLUSIONS: Handgrip exercise echocardiography provides important information regarding the dynamic nature of MR, exercise-induced changes in left ventricular function, and pulmonary circulation with subsequent consequences for further therapeutic decision making. Thus, it should be considered as a diagnostic tool in symptomatic patients with non-severe MR at rest.
Mitral Valve Insufficiency , Humans , Mitral Valve Insufficiency/diagnostic imaging , Mitral Valve Insufficiency/epidemiology , Mitral Valve Insufficiency/complications , Prognosis , Prevalence , Hand Strength , Exercise Test
BACKGROUND: Cytomegalovirus (CMV) infections after heart transplantation (HTx) can cause cardiac allograft vasculopathy. Consequently, monitoring and prophylaxis for cytomegalovirus deoxyribonucleic acid (CMV-DNAemia) within the first weeks after HTx is recommended. METHODS: All patients who underwent HTx between September 2010 and 2021 surviving the first 90 days (n = 196) were retrospectively reviewed. The patients were divided on the prevalence of CMV-DNAemia during the first postoperative year after the end of the prophylaxis. A total of n = 35 (20.1%) developed CMV-DNAemia (CMV group) and were compared to patients without CMV-DNAemia (controls, n = 139). The remaining patients (n = 22) were excluded due to incomplete data. RESULTS: Positive donors and negative recipients (D+/R-) and negative donors and positive recipients (D-/R+) serology was significantly increased and D-/R- decreased in the CMV group (p < .01). Furthermore, the mean age was 57.7 ± 8.7 years but only 53.6 ± 10.0 years for controls (p = .03). Additionally, the intensive care unit (p = .02) and total hospital stay (p = .03) after HTx were approximately 50% longer. Interestingly, the incidence of CMV-DNAemia during prophylaxis was only numerically increased in the CMV group (5.7%, respectively, 0.7%, p = .10), the same effect was also observed for postoperative infections. Multivariate analyses confirmed that D+/R- and D-/R+ CMV immunoglobulin G match were independent risk factors for postprophylaxis CMV-DNAemia. CONCLUSION: Our data should raise awareness of CMV-DNAemia after the termination of regular prophylaxis, as this affects one in five HTx patients. Especially old recipients as well as D+/R- and D-/R+ serology share an elevated risk of late CMV-DNAemia. For these patients, prolongation, or repetition of CMV prophylaxis, including antiviral drugs and CMV immunoglobulins, may be considered.
Cytomegalovirus Infections , Heart Transplantation , Humans , Middle Aged , Aged , Cytomegalovirus/genetics , Retrospective Studies , Cytomegalovirus Infections/epidemiology , Cytomegalovirus Infections/etiology , Cytomegalovirus Infections/prevention & control , Risk Factors , Heart Transplantation/adverse effects
OBJECTIVES: Donor hearts frequently originate from donors whose lungs are also recovered for transplant. Synchronous heart and lung procurement is more complex than procurement ofthe heart alone, and the effects on outcomes are debated. This study examines the effect of synchronous procurement on outcomes in heart transplant recipients. MATERIALS AND METHODS: This single-center study included patients who received a heart transplant from September 2010 to June 2022. Main outcomes were overall mortality and mortality at 30 days, 3 months, 1 year, and 3 years and morbidity within the first year. We analyzed overall mortality using KaplanMeier survival analysis. Logistic regression was used for the remaining outcomes, adjusting for covariates. P < .05 was considered significant. RESULTS: Our study included 253 heart transplant recipients (72.3% male, mean age 55.0 years), of which 184 patients (72.7%) received hearts from donors of heart and lung, and 69 (27.3%) received hearts from donors of only hearts. Heart-and-lung donors were younger than heart-only donors (43.2 vs 47.2 years; P = .017). Transplant recipient baseline characteristics were not different between the 2 groups. Receipt of hearts from heart-and-lung donors was not associated with higher overall mortality (P = .33) or mortality at 3 months (P = .199), 1 year (P = .348), or 3 years (P = .375), and even showed better 30-day survival than receipt of hearts from heart-only donors (p=0.035). Recipients of hearts from heart-and-lung donors did not have higher rates of postoperative mechanical circulatory support, resternotomy, or pacemaker implantation within the first year. CONCLUSIONS: Our study confirms that synchronous heart and lung procurement for transplant is not associated with worse outcomes in heart transplant recipients and that hearts originating from heart-andlung donors may even be associated with improved outcomes.
Heart Transplantation , Pacemaker, Artificial , Humans , Male , Middle Aged , Female , Heart Transplantation/adverse effects , Tissue Donors , Heart , Lung
BACKGROUND: Large Impella systems (5.0 or 5.5; i.e., Impella 5+) (Abiomed Inc., Danvers, MA, USA) help achieve better clinical outcomes through relevant left ventricular unloading in acute cardiogenic shock (CS). Here, we report our experience with Impella 5+, while focusing on the clinical outcomes depending on individual case scenarios in patients with acute CS. METHODS: This single-center retrospective observational study included 100 Impella 5+ implantations conducted on patients with acute CS from November 2018 to October 2021. After excluding 10 reimplantation cases, 90 cases were enrolled for further analysis. RESULTS: In-hospital and 30-day mortality rates were 56.7% (n = 51) and 48.9% (n = 44), respectively. In-hospital mortality was lower in patients with acute myocardial infarction (AMI) than in non-AMI patients (p = 0.07). Young age and low lactate levels were the independent predictors of successful transition and survival after permanent mechanical circulatory support/heart transplantation (pMCS/HTX) (age, p = 0.03; lactate level, p = 0.04; survived after pMCS/HTX, n = 11; died on Impella, n = 41). During simultaneous utilization of venoarterial extracorporeal membrane oxygenation therapy and Impella 5+, termed ECMELLA therapy, high dose of noradrenaline was a predictive factor for in-hospital mortality by multivariate analysis (n = 0.02). CONCLUSIONS: Our results suggest that enhanced Impella support might have better clinical outcomes among acute CS patients supported with large Impella, those with AMI than those with no AMI. Young age and low lactate levels were predictors of successful bridging to pMCS/HTX and favorable clinical outcomes thereafter. The clinical outcomes of ECMELLA therapy might depend on noradrenaline dose at the time of Impella 5+ implantation.
Heart-Assist Devices , Myocardial Infarction , Humans , Shock, Cardiogenic/surgery , Treatment Outcome , Heart-Assist Devices/adverse effects , Myocardial Infarction/complications , Myocardial Infarction/surgery , Retrospective Studies , Norepinephrine , Lactates
Background Neurologic events during primary stay in heart transplant (HTx) recipients may be associated with reduced outcome and survival, which we aim to explore with the current study. Methods and Results We screened and included all patients undergoing HTx in our center between September 2010 and December 2022 (n=268) and checked for the occurrence of neurologic events within their index stay. Neurologic events were defined as ischemic stroke, hemorrhage, hypoxic ischemic injury, or acute symptomatic neurologic dysfunction without central nervous system injury. The cohort was then divided into recipients with (n=33) and without (n=235) neurologic events after HTx. Using a multivariable Cox regression model, the association of neurologic events after HTx and survival was assessed. Recipients with neurologic events displayed a longer intensive care unit stay (30 versus 16 days; P=0.009), longer mechanical ventilation (192 versus 48 hours; P<0.001), and higher need for blood transfusion, and need for hemodialysis after HTx was substantially higher (81% versus 55%; P=0.01). Resternotomy (36% versus 26%; P=0.05) and mechanical life support (extracorporeal life support) after HTx (46% versus 24%; P=0.02) were also significantly higher in patients with neurologic events. Covariable-adjusted multivariable Cox regression analysis revealed a significant independent association of neurologic events and increased 30-day (hazard ratio [HR], 2.5 [95% CI, 1.0-6.0]; P=0.049), 1-year (HR, 2.2 [95% CI, 1.1-4.3]; P=0.019), and overall (HR, 2.5 [95% CI, 1.5-4.2]; P<0.001) mortality after HTx and reduced Kaplan-Meier survival up to 5 years after HTx (P<0.001). Conclusions Neurologic events after HTx were strongly and independently associated with worse postoperative outcome and reduced survival up to 5 years after HTx.
Extracorporeal Membrane Oxygenation , Heart Transplantation , Ischemic Stroke , Humans , Adult , Heart Transplantation/adverse effects , Hypoxia , Postoperative Period , Treatment Outcome , Retrospective Studies
OBJECTIVES: There are several surgical approaches for explanting a left ventricular assist device (LVAD) after recovery of cardiac function. Thus, remaining ventricular assist device components may bear significant risks of infection or thrombosis. We hereby report our technique and two-center experience with explantation of LVADs using a new double-patch technique. METHODS: From March 2019 to April 2021, five patients underwent LVAD explantation after myocardial recovery (HVAD, n = 2; HeartMate 3, n = 3). The mean patient age was 50.3 years (100% male); the mean time on the LVAD was 23.1 ± 20.8 months. The aetiology of the primary heart failure was dilated cardiomyopathy (n = 4) and myocarditis (n = 1).LVAD explantation was performed using a median sternotomy and cardiopulmonary bypass. The LVAD was stopped, and the outflow graft was clamped. The outflow graft was ligated and sutured close to the aortic anastomosis. The driveline was clipped and removed. Under induced fibrillation, the attachment of the LVAD was released from the apical cuff and the LVAD was removed. A round pericardial patch was fixed from the inner of the ventricle. This step sealed the apex of the heart. An additional Gore-Tex patch was continuously sutured epicardially over the suture ring. RESULTS: The 5 cases showed technically uncomplicated explantation of the LVADs. During the follow-up of a mean of 16.4 ± 16.9 months, we observed 100% survival. There were no bleeding complications or thromboembolic events during the follow-up period. CONCLUSIONS: LVAD explantation with the double-patch technique is feasible and safe. This technique allows discontinuation of anticoagulation. The 30-day survival was 100%. Further studies are needed to provide better evidence for LVAD explantation and long-term follow-up.
To investigate the pathogenic mechanisms of calcified aortic valve disease (CAVD), it is necessary to develop a new three-dimensional model that contains valvular interstitial cells (VIC) and valvular endothelial cells (VEC). For this purpose, ovine aortic valves were processed to isolate VIC and VEC that were dissolved in an alginate/gelatin hydrogel. A 3D-bioprinter (3D-Bioplotter® Developer Series, EnvisionTec, Gladbeck, Germany) was used to print cell-laden tissue constructs containing VIC and VEC which were cultured for up to 21 days. The 3D-architecture, the composition of the culture medium, and the hydrogels were modified, and cell viability was assessed. The composition of the culture medium directly affected the cell viability of the multicellular tissue constructs. Co-culture of VIC and VEC with a mixture of 70% valvular interstitial cell and 30% valvular endothelial cell medium components reached the cell viability best tested with about 60% more living cells compared to pure valvular interstitial cell medium (p = 0.02). The tissue constructs retained comparable cell viability after 21 days (p = 0.90) with different 3D-architectures, including a "sandwich" and a "tube" design. Good long-term cell viability was confirmed even for thick multilayer multicellular tissue constructs. The 3D-bioprinting of multicellular tissue constructs with VEC and VIC is a successful new technique to design tissue constructs that mimic the structure of the native aortic valve for research applications of aortic valve pathologies.
Myat Soe Thet et al. published a letter [...].
Today's living world is enriched with a myriad of natural biological designs, shaped by billions of years of evolution. Unraveling the construction rules of living organisms offers the potential to create new materials and systems for biomedicine. From the close examination of living organisms, several concepts emerge: hierarchy, pattern repetition, adaptation, and irreducible complexity. All these aspects must be tackled to develop transformative materials with lifelike behavior. This perspective article highlights recent progress in the development of transformative biohybrid systems for applications in the fields of tissue regeneration and biomedicine. Advances in computational simulations and data-driven predictions are also discussed. These tools enable the virtual high-throughput screening of implant design and performance before committing to fabrication, thus reducing the development time and cost of biomimetic and biohybrid constructs. The ongoing progress of imaging methods also constitutes an essential part of this matter in order to validate the computation models and enable longitudinal monitoring. Finally, the current challenges of lifelike biohybrid materials, including reproducibility, ethical considerations, and translation, are discussed. Advances in the development of lifelike materials will open new biomedical horizons, where perhaps what is currently envisioned as science fiction will become a science-driven reality in the future.
Prostheses and Implants , Tissue Engineering , Reproducibility of Results , Biomimetics/methods
Recreating human tissues and organs in the petri dish to establish models as tools in biomedical sciences has gained momentum. These models can provide insight into mechanisms of human physiology, disease onset, and progression, and improve drug target validation, as well as the development of new medical therapeutics. Transformative materials play an important role in this evolution, as they can be programmed to direct cell behavior and fate by controlling the activity of bioactive molecules and material properties. Using nature as an inspiration, scientists are creating materials that incorporate specific biological processes observed during human organogenesis and tissue regeneration. This article presents the reader with state-of-the-art developments in the field of in vitro tissue engineering and the challenges related to the design, production, and translation of these transformative materials. Advances regarding (stem) cell sources, expansion, and differentiation, and how novel responsive materials, automated and large-scale fabrication processes, culture conditions, in situ monitoring systems, and computer simulations are required to create functional human tissue models that are relevant and efficient for drug discovery, are described. This paper illustrates how these different technologies need to converge to generate in vitro life-like human tissue models that provide a platform to answer health-based scientific questions.
Stem Cells , Tissue Engineering , Humans , Drug Discovery , Drug Delivery Systems , Biocompatible Materials/pharmacology
BACKGROUND: Coronavirus disease 2019 (COVID-19)-related acute respiratory distress syndrome requiring veno-venous extracorporeal membrane oxygenation (vv-ECMO) is related with poor outcome, especially in Germany. We aimed to analyze whether changes in vv-ECMO therapy during the pandemic were observed and lead to changes in the outcome of vv-ECMO patients. METHODS: All patients undergoing vv-ECMO support for COVID-19 between 2020 and 2021 in a single center (n = 75) were retrospectively analyzed. Weaning from vv-ECMO and in-hospital mortality were defined as primary and peri-interventional adverse events as secondary endpoints of the study. RESULTS: During the study period, four infective waves were observed in Germany. Patients were assigned correspondingly to four study groups: ECMO implantation between March 2020 and September 2020: first wave (n = 11); October 2020 to February 2021: second wave (n = 23); March 2021 to July 2021: third wave (n = 25); and August 2021 to December 2021: fourth wave (n = 20). Preferred cannulation technique changed within the second wave from femoro-femoral to femoro-jugular access (p < 0.01) and awake ECMO was implemented. Mean ECMO run time increased by more than 300% from 10.9 ± 9.6 (first wave) to 44.9 ± 47.0 days (fourth wave). Weaning of patients was achieved in less than 20% in the first wave but increased to approximately 40% since the second one. Furthermore, we observed a continuous numerically decrease of in-hospital mortality from 81.8 to 57.9% (p = 0.61). CONCLUSION: Preference for femoro-jugular cannulation and awake ECMO combined with preexisting expertise and patient selection are considered to be associated with increased duration of ECMO support and numerically improved ECMO weaning and in-hospital mortality.
Incidence of SARS-CoV-2 remains high in the population. Consequently, an increasing percentage of reported organ donors are also SARS-CoV-2 positive. Although donors may not have experienced COVID-19-related symptoms, there is a chance of unnoticed cardiovascular effects associated with this disease. Therefore, SARS-CoV-2 donor grafts have been regularly rejected for heart transplantation (HTx) for a long time. We hereby present three consecutive patients receiving grafts from SARS-CoV-2 positive donors (defined by the PCR cycle threshold value < 30). All patients underwent HTx after a previous triple mRNA vaccination (mRNA-BNT162b2 vaccine, Comirnaty) without adverse events and with a regular post-operative course. Cardiovascular magnetic resonance and endomyocardial biopsies confirmed excellent graft function without signs of rejection or viral myocarditis. After a mean follow-up of 135 days after HTx, all patients were in good conditions without heart failure, viral myocarditis, or SARS-CoV-2 infection. Thus, we conclude that HTx with SARS-CoV-2 positive donors seems safe and feasible.
COVID-19 , Myocarditis , Humans , SARS-CoV-2 , BNT162 Vaccine , COVID-19/epidemiology , Tissue Donors , RNA, Messenger
