Showing papers by "Heinz Jakob published in 2018"

The frozen elephant trunk treatment is the operation of choice for all kinds of arch disease.

Abstract: BACKGROUND Frozen elephant trunk (FET) is considered to be the treatment of choice in complex multi-segmental thoracic aortic disease involving the distal arch. Institutional results of FET technique are presented. METHODS From January 2005 to October 2017, 286 patients underwent FET surgery in our department. Patients (mean age 59±11 years) were operated for acute type I (55%) aortic dissection (AD), chronic AD (23%) and aneurysm (22%). Arch repair was performed with the E-vita Open prosthesis under with selective cerebral perfusion and hypothermic circulatory arrest. Zone 2 arch repair was applied in combination with debranching of the left subclavian artery. Redo-surgery after previous sternotomy underwent 52 patients. RESULTS Distal FET was moved from Zone 3 (36%) to Zone 2 (64%) during the past 10 years. Thirty-day mortality was 11% and similar in patients after first or redo-sternotomy (P=1.000). Proximalization of the anastomosis in Zone 2 improved permanent cerebral (4% vs. 8%, P=0.285) as wells as spinal events (2% vs. 4%, P=0.256) though not yet statistically significant. However, postoperative renal (26% vs. 43%, P=0.004) and pulmonary failure (19% vs. 42%, P<0.001) could be decreased significantly. Five-year survival was 75% and also improved with Zone 2 arch repair (P=0.022). Distal aortic arch pathology was excluded in all but one patient. Freedom from re-intervention downstream was 81% and was improved in acute AD compared to chronic AD and aneurysm (P=0.001). Not a single endoleak type I was encountered with this surgical-endovascular approach. CONCLUSIONS FET is the surgical treatment option of choice to achieve lasting results down to the stent-graft end for all comers with all kinds of arch disease and facilitates additional endovascular or surgical treatment downstream, if required. FET in combination with debranching enabling Zone 2 arch repair improved the results. However, FET remains major surgery and less invasive techniques including complete endovascular arch repair methods are welcome to increase our treatment armamentarium especially in frail multi-morbid patients.

Mitochondrial and Contractile Function of Human Right Atrial Tissue in Response to Remote Ischemic Conditioning

Abstract: Background Remote ischemic preconditioning ( RIPC ) by repeated brief cycles of limb ischemia/reperfusion attenuates myocardial ischemia/reperfusion injury We aimed to identify a functional parameter reflecting the RIPC -induced protection in human Therefore, we measured mitochondrial function in right atrial tissue and contractile function of isolated right atrial trabeculae before and during hypoxia/reoxygenation from patients undergoing coronary artery bypass grafting with RIPC or placebo, respectively Methods and Results One hundred thirty-seven patients under isoflurane anesthesia underwent RIPC (3×5 minutes blood pressure cuff inflation on the left upper arm/5 minutes deflation, n=67) or placebo (cuff uninflated, n=70), and right atrial appendages were harvested before ischemic cardioplegic arrest Myocardial protection by RIPC was assessed from serum troponin I/T concentrations over 72 hours after surgery Atrial tissue was obtained for isolation of mitochondria ( RIPC /placebo: n=10/10) Trabeculae were dissected for contractile function measurements at baseline and after hypoxia/reoxygenation (60 min/30 min) and for western blot analysis after hypoxia/reoxygenation ( RIPC /placebo, n=57/60) Associated with cardioprotection by RIPC (26% decrease in the area under the curve of troponin I/T), mitochondrial adenosine diphosphate-stimulated complex I respiration (+10%), adenosine triphosphate production (+46%), and calcium retention capacity (+37%) were greater, whereas reactive oxygen species production (-24%) was less with RIPC than placebo Contractile function was improved by RIPC (baseline, +7%; reoxygenation, +24%) Expression and phosphorylation of proteins, which have previously been associated with cardioprotection, were not different between RIPC and placebo Conclusions Cardioprotection by RIPC goes along with improved mitochondrial and contractile function of human right atrial tissue Clinical Trial Registration URL: https://wwwclinicaltrialsgov Unique identifier: NCT 01406678

Intravascular ultrasound assisted sizing in thoracic endovascular aortic repair improves aortic remodeling in Type B aortic dissection.

Abstract: The precise sizing of the stent graft in thoracic endovascular aortic repair (TEVAR) affects aortic remodeling and hence, further outcome. Covering the proximal entry tear is essential for successful treatment of Type B aortic dissection. Intravascular ultrasound (IVUS) enables real-time aortic diameter assessment, and is especially useful when computed tomography (CT) image quality is poor. IVUS, however, is not routinely utilized due to cost inefficiency. We investigated the impact of IVUS-assisted stent graft sizing on aortic remodeling in TEVAR. In this single-center retrospective study we evaluated patients with Type B aortic dissection undergoing both CT and IVUS before TEVAR. We assessed the aortic diameter at the level of the left subclavian artery via both methods before stent implantation and analyzed due to which method the implanted stent graft was chosen, retrospectively. To determine the degrees of aortic remodeling involved, we evaluated true lumen and false lumen diameters, and total aortic remodeling in CT. We analyzed 45 patients with Type B aortic dissection undergoing TEVAR. The mean ages were 66.9±10.0 years fo0072 IVUS (n = 20) and 62.3±14.2 years for CT-assisted TEVAR (n = 25; p = 0.226). The follow-up time for both groups did not differ between the two groups (IVUS: 22.9±23.1 months, CT: 25.6±23.0 months; p = 0.700). While both methods were associated with advantages regarding aortic remodeling, IVUS-assisted sizing yielded a greater increase in true lumen (30.4±6.2 vs. 25.6±5.3; p = 0.008) and reductions in false lumen (14.4±8.5 vs. 23.9±9.3; p = 0.001) and total aortic diameter (35.5±6.0 vs. 39.9±8.1; p = 0.045). IVUS-guided stent graft sizing in Type B aortic dissection shows beneficial effects on aortic remodeling and might be of additional advantage in aortic diseases, especially when CT image quality is poor.

One-year experience with ex vivo lung perfusion: Preliminary results from a single center.

Abstract: Objective:To enlarge the donor pool for lung transplantation, an increasing number of extended criteria donor lungs are used. However, in more than 50% of multi-organ donors the lungs are not used....

Infections after transcatheter versus surgical aortic valve replacement: mid-term results of 200 consecutive patients.

Abstract: Background: Transcatheter aortic valve implantation (TAVI) is the standard therapy for high-risk patients with aortic stenosis (AS). TAVI-outcomes are widely investigated in comparison to surgical aortic valve replacement (SAVR), but less is known about infectious complications after TAVI. We aimed to compare early and mid-term infectious outcomes of patients undergoing TAVI or SAVR. Methods: The present study is a prospective single-centre study including 200 consecutive patients between 06/2014–03/2015 undergoing TAVI (either transfemoral or transapical and transaortic, n=47+53=100) or SAVR (either isolated or concomitant with CABG, n=52+48=100). The mean age and log. EuroSCORE were significantly different between both groups (81±6 versus 69±11 years, P Results: Primary endpoints showed no difference in overall TAVI- versus SAVR-groups regarding respiratory- (14% versus 19%, P=0.45), urinary-tract (7% versus 4%, P=0.54) infections, sepsis (5% versus 6%, P=1.0), endocarditis (0% versus 1%, P=1.0) or 30-day mortality (10% versus 4%, P=0.09), except for wound disorders, which were significantly lower in the TAVI-group (1% versus 8%, P=0.035), respectively. Secondary endpoints reported no difference regarding infectious related rehospitalisation (4% versus 4%, P=1.0), but significantly higher 2-year mortality (28% versus 16%, P=0.048) in the TAVI-group. Conclusions: So far, little has been studied about infectious complications after TAVI. This study reports no difference between the overall TAVI and SAVR groups regarding infectious complications. However, SAVR group show more wound healing disorders but less mortality than TAVI group.

Accuracy of myocardial viability imaging by cardiac MRI and PET depending on left ventricular function

Abstract: Accuracy of myocardial viability imaging by cardiac MRI and PET depending on left ventricular function

Transcatheter versus Surgical Aortic Valve Replacement after Previous Cardiac Surgery: A Systematic Review and Meta-Analysis.

Abstract: Aim. Aortic valve replacement (AVR) in patients with prior cardiac surgery might be challenging. Transcatheter aortic valve replacement (TAVR) offers a promising alternative in such patients. We therefore aimed at comparing the outcomes of patients with aortic valve diseases undergoing TAVR versus those undergoing surgical AVR (SAVR) after previous cardiac surgery. Methods and Results. MEDLINE, EMBASE, and the Cochrane Central Register were searched. Seven relevant studies were identified, published between 01/2011 and 12/2015, enrolling a total of 1148 patients with prior cardiac surgery (97.6% prior CABG): 49.2% underwent TAVR, whereas 50.8% underwent SAVR. Incidence of stroke (3.8 versus 7.9%, ) and major bleeding (8.3 versus 15.3%, ) was significantly lower in the TAVR group. Incidence of mild/severe paravalvular leakage (14.4/10.9 versus 0%, ) and pacemaker implantation (11.3 versus 3.9%, ) was significantly higher in the TAVR group. There were no significant differences in the incidence of acute kidney injury (9.7 versus 8.7%, ), major adverse cardiovascular events (8.7 versus 12.3%, ), 30-day mortality (5.1 versus 5.5%, ), or 1-year mortality (11.6 versus 11.8%, ) between the TAVR and SAVR group. Conclusions. TAVR as a redo procedure offers a safe alternative for patients presenting with aortic valve diseases after previous cardiac surgery especially those with prior CABG.

Hemodynamic changes lead to alterations in aortic diameters and may challenge further stent graft sizing in acute aortic syndrome.

Abstract: Background: Precise stent graft sizing in Thoracic endovascular aortic repair (TEVAR) is crucial to receive optimal long-term results. Computed tomography (CT), as the current standard in assessing aortic diameters (ADs), is often performed at initial diagnosis. Since several acute aortic diseases are associated with blood loss and/or volume re-distribution, assessed AD might be influenced by impaired hemodynamic conditions. Intravascular ultrasound (IVUS) offers real-time assessment, especially after hemodynamic restoration, and might help for stent graft choice. Methods: We investigated the correlation between CT and later IVUS measurements in elective (n=83) and emergency patients (n=32) at the level distal to the left subclavian artery (LSA), a frequent proximal landing zone in TEVAR. Patients were grouped depending on their shock index (heart rate/systolic blood pressure): emergency patients with diagnosis of acute aortic syndrome, urgently required treatment after admission and had a shock index >1, otherwise were grouped as elective. Basic hemodynamics were assessed for both groups at admission and at definite IVUS-procedure. Results: At time of admission the emergency group showed lower blood pressure (99±19.8 vs . 141±24 mmHg; P=0.001) and higher heart rate (98±13 vs . 70±12 bpm; P=0.001) compared to elective patients. By hemodynamic stabilization comparable blood pressure and heart rate were achieved in both groups at time of IVUS. In the emergency group, we found a significantly increase in AD after hemodynamic stabilization, whereas the diameters did not change in the elective group (IVUS mean vs . CT mean : 5.1±1.0 vs . 0.4±2.2 mm; P=0.001 and IVUS min vs . CT mean : 3.9±1.3 vs . −0.3±2.2 mm; P=0.011). Conclusions: IVUS for stent graft sizing is a valuable approach during TEVAR, especially in the light of emergency treatment by offering real-time assistance. Impaired hemodynamic conditions might lead to relevant changes in AD and may strongly influence stent graft choice. In these cases, careful stent graft selection might contribute to avoidance of stent graft related complication.

Serum markers for early detection of patients with mesenteric ischemia after cardiac surgery.

Abstract: Objective Mesenteric ischemia (MESI) is a rare but often fatal complication in patients after cardiac surgery. Non-specific clinical symptoms and lack of specific laboratory parameters complicate the diagnosis. We evaluated potential serum markers for MESI in cardiac surgery patients. Methods Between March and October 2012, serial serum samples of 567 elective cardiac surgery patients were collected 1, 24, and 48 h after the operation, and concentrations of potential markers for MESI [α-glutathione-S-transferase (αGST), intestinal fatty-acid-binding protein (iFABP), and D-lactate] were measured retrospectively. In patients requiring laparotomy, blood samples obtained 72, 48, 24, and 12 h before the laparotomy were additionally measured and compared to all other patients (control group). Results Laparotomy was performed in 18 patients at 11±7 days after cardiac surgery. MESI was found in 9/18 patients. Already 1 h after cardiac surgery, the serum concentrations of D-lactate (37±18 vs. 25±20 nmol/mL, p<0.01) and αGST (82±126 vs. 727±1382 μg/L, p<0.01) in patients undergoing laparotomy were increased compared to the control group. Between patients with and without MESI, differences were only found for iFABP 24 h after cardiac surgery (1.1±0.4 vs. 2.9±0.6 ng/mL, p=0.04) and up to 72 h before laparotomy (0.56±0.72 vs. 2.51±1.96 ng/mL, p=0.01). Conclusions D-lactate and αGST were early markers for gastrointestinal complications after cardiac surgery. Before laparotomy, lowered iFABP levels indicated MESI. Routinely used, these markers can help identify patients with gastrointestinal complications after cardiac surgery early, and might be useful for the evaluation of new therapeutic or preventive strategies.

Histidine metabolism after Bretschneider cardioplegia in cardiac surgical patients.

Abstract: Bretschneider (histidine-tryptophan-ketoglutarate) solution with its high histidine concentration (198 mM) is one of many cardioplegic solutions, which are routinely used for cardiac arrest. The aim of this study was to evaluate the physiological biochemical degradation of administered histidine to histamine and its major urinary metabolite N-methylimidazole acetic acid. A total number of thirteen consecutive patients scheduled for elective isolated coronary artery bypass grafting with cardiopulmonary bypass were enrolled in the prospective observational designed study at the Department of Thoracic and Cardiovascular Surgery between 04/2016 and 06/2016. Patients received 1.7 l Bretschneider solution on average. Before and at the end of operation as well as in the postoperative course, urine samples gathered from the urinary catheter bag were analyzed. During the operative period, urinary histidine concentration significantly increased from 29 micromol/mmol creatinine to 9,609 micromol/mmol creatinine. Postoperatively, histidine excretion reduced while histamine as well as N-methylimidazole acetic acid excretion rose significantly. Patients showed elevated levels of histidine, histamine as well as N-methylimidazole acetic acid in urine, but no unmanageable hemodynamic instability possibly arising from the histamine's biological properties. Chemically modified histidine might reduce uptake and metabolization while maintaining the advantages of buffer capacity.

Impact of Acute Intestinal Ischemia and Reperfusion Injury on Hemodynamics and Remote Organs in a Rat Model

Abstract: Background Acute mesenteric ischemia following cardiovascular surgery is a rare but fatal complication. We established a new rat model for hemodynamic monitoring during mesenteric ischemia/reperfusion (I/R) and evaluated the impact of mesenteric I/R on hemodynamics and remote organ injury. Methods Mesenteric I/R was induced in male Wistar rats by superior mesenteric artery occlusion for 90 minutes, followed by 120 minutes of reperfusion. Before I/R, ventilation and hemodynamic monitoring including mean arterial blood pressure (MAP) and cardiac output (CO) were established. During reperfusion Geloplasma (I/R + Geloplasma, N = 6) and Ringer's solution (I/R + Ringer, N = 6) were titrated according to CO and compared with I/R without volume resuscitation (I/R only, N = 6) and a sham group (sham, N = 6). Blood samples were regularly taken for serum marker measurements. After reperfusion organs were harvested for histology studies. Results After acute mesenteric I/R, MAP and CO decreased (p Conclusion A new model for CO monitoring after mesenteric I/R injury demonstrated severe hypovolemic shock during reperfusion followed by remote myocardial and lung injury. Far less colloid volume is needed for hemodynamic stabilization after I/R compared with crystalloid volume.

Endoscopy in aortic valve repair: does it worth it?

Abstract: Background: Aortic valve repair (AVR) is a technically challenging procedure. Usually, the repaired valve is checked after weaning from cardiopulmonary bypass (CPB). We aimed to evaluate intraoperative and clinical outcomes of AVR patients in whom intraoperative aortic root endoscopy was applied. Methods: The present study was a retrospective single-center study. An autoclavable video-scope was used to evaluate aortic valve. During endoscopy, crystalloid cardioplegia was administered to pressurize the aortic root. Primary endpoints were: need for Re-CPB after weaning from bypass and early postoperative aortic valve regurgitation. Secondary endpoints included: 30-day mortality and freedom from aortic regurgitation/reoperation during follow-up. Results: A total of 66 consecutive patients who underwent AVR (05/2014–03/2017) were evaluated. Patients mean age was 53.5±14.5 years and 74.2% were male. Seventy-three percent of the patients were in New York Heart Association (NYHA) functional class III/IV. The main underlying aortic valve pathology was aortic valve regurgitation in 83.3%, 9.1% aortic stenosis and combination of both in 7.6%. A tricuspid or bicuspid aortic valve was observed in 48.5% and 43.9%, respectively, whereas 7.6% showed a functional unicuspid aortic valve. Intraoperative results revealed endoscopy as a helpful tool, where second time cross-clamp was avoided in most (58, 87.9%) of patients. Thirty-day mortality was 3.0%. During follow-up (28±10 months), 2 patients required re-operation due to recurrent aortic valve regurgitation. Conclusions: The present analysis showed, that intraoperative aortic valve endoscopy is a helpful tool to evaluate AVR before weaning from bypass. This easy-to-use tool gives real-time information about the intraoperative result and might provide additional guidance to achieve optimal results after AVR.

The Fluid Dynamical Performance of the Carpentier-Edwards PERIMOUNT Magna Ease Prosthesis

Abstract: The aim of the present in vitro study was the evaluation of the fluid dynamical performance of the Carpentier-Edwards PERIMOUNT Magna Ease depending on the prosthetic size (21, 23, and 25 mm) and the cardiac output (3.6-6.4 L/min). A self-constructed flow channel in combination with particle image velocimetry (PIV) enabled precise results with high reproducibility, focus on maximal and local peek velocities, strain, and velocity gradients. These flow parameters allow insights into the generation of forces that act on blood cells and the aortic wall. The results showed that the 21 and 23 mm valves have a quite similar performance. Maximal velocities were 3.03 ± 0.1 and 2.87 ± 0.13 m/s; maximal strain Exx , 913.81 ± 173.25 and 896.15 ± 88.16 1/s; maximal velocity gradient Eyx , 1203.14 ± 221.84 1/s and 1200.81 ± 61.83 1/s. The 25 mm size revealed significantly lower values: maximal velocity, 2.47 ± 0.15 m/s; maximal strain Exx , 592.98 ± 155.80 1/s; maximal velocity gradient Eyx , 823.71 ± 38.64 1/s. In summary, the 25 mm Magna Ease was able to create a wider, more homogenous flow with lower peak velocities especially for higher flow rates. Despite the wider flow, the velocity values close to the aortic walls did not exceed the level of the smaller valves.

Ex-vivo-Lungenperfusion

Abstract: In Deutschland werden nur 40–50 % der Lungen von Multiorganspendern transplantiert. Daher ist es von besonderer Bedeutung, moglichst jedes potenziell transplantable Spenderorgan zu verwenden. Mit dem Verfahren der normothermen Ex-vivo-Lungenperfusion (EVLP) besteht die Moglichkeit, Spenderlungen genauer zu evaluieren, die zuvor als nichttransplantabel eingestuft wurden. Das Verfahren der normothermen, azellularen EVLP wird detailliert beschrieben. Dabei wird ausfuhrlich auf die praktische Handhabung eingegangen. Seit Januar 2016 wurden im Westdeutschen Lungenzentrum 56 Lungentransplantationen durchgefuhrt. Elf initial nicht den Standardkriterien entsprechende Spenderlungen wurden mithilfe der EVLP evaluiert und 9 davon transplantiert. Entsprechend dem Toronto-Protokoll wurden die Lungen fur 4 h konditioniert; vor der Lungentransplantation (LuTx) sollte die Differenz des Sauerstoffpartialdruckes (Δ pO2/FIO2-Wert) zwischen arterieller und venoser Perfusionslosung >350 mmHg betragen. In einer retrospektiven Analyse wurden Spender- und Empfangerdaten, Organperfusionsdaten und der postoperative Verlauf untersucht. Das mittlere Spenderalter (Jahre) war fur LuTx 54 ± 14 und 51 ± 8 fur non-LuTx (nichtsignifikant, n. s.). Vor Entnahme betrug der Sauerstoffpartialdruck (pO2) bei einer inspiratorischen Sauerstofffraktion (FIO2) von 1,0: LuTx 324 ± 72 mmHg vs. non-LuTx 382 ± 88 mmHg (n. s.). Die Beatmung der Spender dauerte: LuTx 104 ± 44 h, non-LuTx 245 ± 180 h (n. s.). Der ∆ pO2/FIO2-Wert nach 4 h wurde fur LuTx mit 389 ± 49 mmHg und fur non-LuTx mit 254 ± 0 mmHg bestimmt (n. s.). Die „Out-of-body“-Zeit nach Implantation der zweiten Lunge betrug 724 ± 133 min. Die postoperative Beatmungsdauer umfasste 232 ± 305 h und der Intensivstationsaufenthalt 274 ± 293 h. Die Dreisigtagesterblichkeit wurde mit 9 % berechnet. Die normotherme EVLP kann als sicheres Verfahren zur Evaluation initial nichttransplantabler Spenderlungen verwendet werden. Diese Erfahrungen eines Einzelzentrums zeigen, dass eine Verwendung von 81 % der zunachst als nichttransplantabel eingestuften Spenderlungen moglich ist. Die perioperativen Ergebnisse sind mit denen der Standardtransplantation vergleichbar.

Transcatheter Aortic Valve Implantation in Aortic Valve Regurgitation

Abstract: Transcatheter aortic valve implantation (TAVI) has been initially considered as an alternative for high-risk patients with aortic stenosis. Although the current experience is limited, TAVI might be also an alternative to treat patients with pure, severe aortic regurgitation. The present article describes all currently available transcatheter aortic valves, which have been used (mainly off-label) in patients presenting with pure aortic regurgitation. Although the current experience is limited and larger multicenter studies or registries are warranted, the concept of TAVI in pure aortic regurgitation is feasible and might be an alternative option.

Extrakranielle Karotisstenose beim herzchirurgischen Patienten

Abstract: Die optimale Therapie von herzchirurgischen Patienten mit koexistierender schwerer koronarer und karotidaler Atherosklerose zur Reduzierung des Schlaganfallrisikos wird kontrovers diskutiert. Bis heute besteht keine hohe Evidenz fur einen Vorteil der kombinierten Karotisrevaskularisation und koronaren Bypassoperation („coronary artery bypass grafting“, CABG) gegenuber der isolierten CABG. Wahrend eine Karotisrevaskularisation bei symptomatischer Karotisstenose, unilateralen asymptomatischen Karotisstenosen mit aufgehobener zerebraler Reservekapazitat, hochgradiger asymptomatischer Karotisstenose mit kontralateralem Verschluss oder hochgradigen asymptomatischen bilateralen Karotisstenosen (kumulativ >140 %) vorteilhaft sein kann, ist dies fur die uberwiegende Mehrheit der asymptomatischen Karotisstenosen nicht gesichert. Bislang wird daher empfohlen, die Indikation zur Karotisrevaskularisation bei Herzoperationen zuruckhaltend zu stellen.

Impact of Normothermic Ex-vivo-lung Perfusion on Early Post Transplantation Cytomegalovirus Infection

Abstract: Lung transplantation became a standard procedure in patients with end stage lung disease but despite optimized donor management only 40–50% of lungs from multiorgan-donors are transplanted. To overcome the shortness of donor organs, extended criteria donor (ECD) lungs are more frequently evaluated for transplantation by use of normothermic ex vivo lung perfusion (EVLP) (1). Previous studies showed that these lungs after pretransplant check can be transplanted with good results (2). Nakajima reported that EVLP treatment with broad spectrum antibiotics significantly reduced the bacterial burden and endotoxin levels in infected donor lungs (3). Despite antimicrobial and antiviral prophylaxis infections are major contributors to morbidity and mortality after Original Article

Frozen Elephant Trunk und E‑vita-open-Hybridprothese

Abstract: Das Frozen-Elephant-Trunk-Verfahren ist eine Weiterentwicklung der konventionellen Elephant-Trunk-Technik und ermoglicht die einzeitige Behandlung von Aortenerkrankungen, die sich uber den Aortenbogen und die Aorta descendens ausbreiten. Zudem wird durch diese Technik eine weitere endovaskulare oder offene chirurgische Therapie bei residualen Befunden erleichtert. Die angewendete Hybridprothese besteht aus einer Gefasprothese fur den Ersatz des Aortenbogens und die Reimplantation der Kopfgefase sowie einem Stent-Graft zur Behandlung der Aorta descendens. Der vorliegende Beitrag beschreibt die technischen Aspekte und die Erfahrung der Autoren mit der E‑vita-open-Hybridprothese.