In vivo evaluations of a new thromboresistant polyurethane for artificial heart blood pumps

To reduce the risk of thromboembolic complications in prosthetic blood pumps, we have developed a new segmented polyurethane elastomer. This material is unique because its mechanical properties for long-term durability and surface properties for biocompatibility have been separated and developed in two distinct materials. Improved thromboresistance is then obtained by a 1% concentration of a new polymeric surface-modifying additive blended with the base polyurethane before fabrication of the blood pump. To evaluate this material in vivo, we performed 10 implants, in calves, of the Pierce-Donachy prosthetic ventricle with blood-pumping sacs and cannulas fabricated from the new surface-modifying additive copolymer blend (Thoratec's BPS-215M). In four control implants the blood sacs and cannulas were fabricated from Ethicon's Biomer segmented polyurethane, which is the present clinical standard for most artificial hearts and circulatory support devices. The blood pumps were connected from the apex of the left ventricle to the descending aorta in male Holstein calves weighing 82 to 108 kg and were driven pneumatically in the full-to-empty mode with flows averaging 5 to 6 L/min. Each calf was medicated with aspirin and dipyridamole throughout the study period and was electively put to death after 4 weeks for evaluation of explanted blood sacs and for examination of the kidneys for infarction. All 10 explanted blood sacs made with the surface-modifying additive copolymer blend were shiny and completely free of thrombus. Three of the four explanted Biomer blood sacs showed visible red thrombus, and all four showed small areas of white thrombus. The average surface area of the Biomer blood sacs covered with thrombus was 45 +/- 32 mm2. Use of a semiquantitative scale to assess renal infarction demonstrated that nine of 10 animals with a surface-modifying additive copolymer blend blood sac had infarction less severe than the mean infarct score of the animals with a Biomer sac. The surface-modifying additive copolymer blend has excellent mechanical and physical properties necessary for use in artificial heart blood pumps. From these experiments, we conclude that the surface-modified polyurethane blend is superior to Biomer polyurethane in blood compatibility and in freedom from thromboembolic risk. This material is now approved by the Food and Drug Administration for investigational device exemption studies in the Pierce-Donachy prosthetic ventricle.     

Computational flow visualization in vibrating flow pump type artificial heart by unstructured grid

Computational flow visualization in the casing of vibrating flow pump (VFP) was made for various conditions based on the novel techniques of fluid dynamics. VFP type artificial heart can generate the oscillated flow and can be applied to the left ventricular assist device. Flow pattern of blood in an artificial heart is closely connected to mechanical performance and serious biomechanical problems such as hemolysis and blood coagulation. To effectively design the VFP for a left ventricular assist device, the numerical codes for solving Navier-Stokes equations were developed for three-dimensional blood flow based on the finite volume method. Furthermore, the simulation techniques based on the artificial compressibility method and the unstructured grid were also developed here. The numerical calculations were based on the precise configurations and the flow conditions of the prototype device. From the viewpoint of computational fluid dynamics (CFD), the detailed discussion of flow patterns in the casing of VFP, which were closely connected with hemolysis and blood coagulation, was made and the computational results were visualized by the use of the recent technique of computational graphics. Some useful design data of VFP were presented.     

Implantation of one piece biventricular assist device by left thoracotomy in an ovine model

In this report, we describe an operative procedure for our implantable 1 piece biventricular assist device (BiVAD) based on a moving actuator mechanism, using an ovine model. Our implantable BiVAD is a volumetric coupled 1 piece unit including right and left blood sacs and an actuator assembly based on the moving actuator mechanism. The BiVAD was controlled by fixed rate control with 75 bpm for the most part. Both the left and the right full ejection modes with the maximum stroke angle were selected to minimize blood stasis in the blood sacs because of low assist flow condition. Three Corriedale sheep were used for the device implantation by a left thoracotomy incision. Cannulation was successfully performed in all cases. Although exposability of the right atrial appendage varied from animal to animal, the insertion of the cannula was easily performed. The cannulas were connected to the pump-actuator assembly in the preperitoneal pocket. All 3 animals survived the experimental procedure. During implantation of the device, in the 1 month survival animal, pump flow was maintained between 2.0 L/min and 2.5 L/min, mean aortic pressure was 90-110 mm Hg, and mean pulmonary artery pressure was 20-30 mm Hg. The left and right atrial pressure were maintained between 0 and 5 mm Hg. In conclusion, this ovine model for implantation of the 1 piece BiVAD can be an effective alternative for testing in vivo biocompatibility of the device although it needs more consideration for anatomical fittability for future human application.     

A constricting ring structure within the wall of the inguinal hernia sac in infants and children and its role in the occurrence of incarceration

The study aims to demonstrate the presence of a fibrous or fibromuscular ring structure within the wall of the sacs of inguinal hernia in children and its importance in the development of incarceration as a direct cause of this complication. A case series study of 784 children with unilateral inguinal hernias operated on over a period of 9 years (1992–2000) in two teaching hospitals (Mosul, Iraq). All underwent herniotomy. The sacs were examined for the presence of a ring structure, and the excised sacs containing the rings were studied histopathologically. The presence of the hernia sac ring (HSR) and its significance in the causation of incarceration was studied. Out of 784 cases, 660 were elective and 124 incarcerated hernias. In 56 sacs the hernia sac ring (HSR) was present — 36 rings in the elective and 20 rings in the sacs of incarcerated hernias. The histopathology of the hernia sac ring was fibrous or fibromuscular tissue. This ring has its significance in the development of incarceration. Hernias with the HSR are three times more liable to incarceration than those without the ring. Incarcerations of inguinal hernia in children are usually caused by the inguinal rings. Another cause for incarceration being studied is a fibrous or fibromuscular ring structure identified within the wall of the hernial sac, causing the incarceration in 5.6% of elective (nonincarcerated) hernias and 16% of incarcerated hernia patients. Patients with these hernia sac rings are three times more liable to incarceration than others.     

Standardization of tibial fractures in the rat.

The influence of the fracture level on the biomechanical properties of healing rat tibial fractures has not been investigated so far, despite the widespread use of rats in fracture healing studies. Fractures were produced in four different zones in the right rat tibia and immobilized with a K-wire. A fifth group of rats was not fractured. After 40 days of healing the fractures and the non-fractured bones were tested in three-point bending. A distinct correlation was found between fracture level and mechanical parameters: maximum load, maximum stiffness, and maximum stress decreased the more distal the fracture was located. In the non-fractured bones, maximum load and maximum stress were constant in all four zones tested, whereas energy absorption increased in the distal part of the tibia. No influence of the healing fracture was found on the contralateral, non-fractured tibia, compared with the animals left undisturbed, and the mechanical properties of the right and the left tibia were found to be symmetrical in terms of mean values. Four different methods of determining the area moment of inertia were investigated, and the simple method of approximating the cross section to an elliptical annulus was found to correlate well with the area moment of inertia, determined from computer tracings of bone slices prepared from the test specimens after the bending test. The computer tracings were corrected for the compression of the specimens caused by the mechanical test.     

Origin of Endolymphatic Sac Tumor

Autopsy temporal bone sections showing a one mm papillary glandular neoplasm, confined to the left endolymphatic duct, are described. This is the second literature report confirming the post-mortem site of origin of the “endolymphatic sac tumor”. The patient died after surgery for right vestibular schwannoma, but no features of von Hippel Lindau disease or neurofibromatosis 2 had been displayed clinically or at autopsy. A study of the epithelium of normal human mature endolymphatic ducts and sacs (EDSs) in archival temporal bone sections showed hyperplastic tubular outgrowths, usually situated in the intraosseous portion of the endolymphatic sac, in most cases. Such appearances imply that the epithelium of the EDS has the potential of producing a malignant papillary glandular neoplasm. Papillary ingrowths, some forming collagenous polypoid projections, and cysts were frequent among the epithelial cells. Psammoma bodies were present in the ducts and sacs of older patients. Appearances suggesting erosion of the bony interface of vestibular aqueduct with EDS could be ascribed to the entry and exit of blood vessels into and from the vestibular aqueduct. Care should be taken in the evaluation of surgical or autopsy material from EDSs not to overcall any of these normal features as malignant.     

Double chambered ventricles: A retrospective clinicopathological study

Introduction Double chambered ventricle is a rare congenital cardiac anomaly, where the ventricular chamber is wholly or partially partitioned usually by abnormal muscular ridges. Double chambered right ventricle (DCRV) is more common than double chambered left ventricle (DCLV). Methods A retrospective observational morphological study of 31 autopsied hearts during a 16-year period highlighted the varied clinical presentations of this pathology and the associated per-operative problems. Results DCRV was found to exist not only with simple cardiac pathologies such as ventricular septal defect and tetralogy of Fallot, but also more complex pathologies such as transposition of great arteries, double outlet right ventricle, left atrial isomerism, and Ebsteins anomaly of tricuspid valve. Double chambered left ventricle in our series was an associated asymptomatic anomaly. Conclusions Closure of the ventricular septal defect may result in isolated DCRV causing proximal right ventricular (RV) hypertension. Postoperative RV dysfunction may compound the ill effects of missed DCRV, RV hypertension and pulmonary hypertension, if any. Double chambered left ventricle may present as an associated asymptomatic anomaly.     

腹股沟疝和股疝的多排螺旋CT鉴别诊断

目的探讨多排螺旋CT（multi—detectorrOWCT,MDCT）在腹股沟疝和股疝鉴别诊断中的价值。方法回顾性分析2012年10月1日至2013年10月31日期间笔者所在医院经临床证实为腹股沟区疝的260例患者的MDCT多平面重组（multi—planerreconstruction,MPR）图像资料,观察疝囊与腹股沟区解剖结构的关系。结果260例患者中,腹股沟斜疝146例,直疝82例,股疝32例。146例斜疝患者（右侧75例,左侧60例,双侧11例,共157个疝囊）的疝囊于腹壁下动脉外侧经腹股沟深环进入腹股沟管,疝囊主要位于精索或子宫圆韧带前侧（103／157,65．6％）或前内侧（36／157,22．9％）。82例直疝患者（右侧39例,左侧34例,双侧9例,共91个疝囊）的疝囊位于腹壁下动脉内侧,主要位于精索内侧（70／91,76．9％）。斜疝及直疝的疝囊均走行于腹股沟韧带前上方。32例股疝患者（右侧17例,左侧15例,共32个疝囊）的疝囊均位于“影像学股三角”内。结论MDCT的MPR手段能准确诊断腹股沟疝与股疝,且借助标志性解剖结构能进行可靠的鉴别诊断。     

Dose-dependent response of gamma irradiation on mechanical properties and related biochemical composition of goat bone-patellar tendon-bone allografts

We studied the effects of gamma irradiation on the dimensions, mechanical and material properties, and mature hydroxypyridinium crosslink density of collagen in goat patellar tendon-bone specimens. Left and right patellar tendon-bone units were removed from 10 adult female goats and were bisected longitudinally. Each tendon half was frozen, and then the left halves were exposed to 4, 6, or 8 Mrad (40,000,60,000, or 80,000 Gy) of gamma irradiation. The contralateral tendon halves served as controls (no irradiation). Each specimen then was loaded to failure in tension, and its soft-tissue midsubstance was processed to measure collagen content and hydroxypyridinium crosslink density. Dose-dependent reductions in the mechanical properties were found, including 46% (p < 0.01) and 18% (p < 0.05) reductions in maximum force and stiffness, respectively, at 4 Mrad. Similar reductions were noted in material properties, including 37% (p < 0.005) and 8% (p > 0.05) reductions in maximum stress and modulus, respectively, at 4 Mrad. These results are consistent with our previous report involving 2 and 3 Mrad (20,000 and 30,000 Gy) of exposure. We also found significant decreases in hydroxypyridinium crosslink density with 6 Mrad of irradiation (p < 0.05). However, since only one biomechanical parameter (modulus) correlated significantly with only one biochemical measure (hydroxypyridinium crosslink density) (p < 0.05), other possible mechanisms also are being explored to more fully explain these dose-dependent changes.     

多层螺旋CT对腹股沟疝的分型鉴别及应用价值

目的分析多层螺旋CT对腹股沟疝的分型鉴别及应用价值。 方法选择2018年5月至2021年3月于宁国市人民医院外科收治的102例腹股沟疝患者作为研究对象，观察分析多层螺旋CT检查斜疝、直疝、股疝的类型，多层螺旋CT诊断与手术结果对比，多层螺旋CT检查的诊断效能，多层螺旋CT横断位、冠状位及矢状位的诊断符合率，多层螺旋CT检查腹股沟疝的影像学征象。 结果102例患者中单纯性斜疝70例，单纯性直疝20例，单纯性股疝5例，左侧复发性腹股沟直疝2例，右侧嵌顿性腹股沟股疝5例。CT诊断与手术结果相符的斜疝占64.71%（66/102），直疝占16.67%（17/102），股疝占6.86%（7/102）。多层螺旋CT诊断斜疝的特异度、灵敏度、阳性预测值分别为8.33%、91.67%、91.67%；直疝的特异度、灵敏度、阳性预测值分别为15.00%、85.00%、85.00%；股疝的特异度、灵敏度、阳性预测值分别为30.00%、70.00%、70.00%。多层螺旋CT冠状位的诊断符合率为99.02%，稍高于矢状位的98.04%（P>0.05）；冠状位的诊断符合率为99.02%，明显高于横断位的75.49%（P<0.05）；矢状位的诊断符合率为98.04%，明显高于横断位的75.49%（P<0.05）。102例患者共有疝囊105个，斜疝患者有72个疝囊，直疝患者有23个疝囊，股疝患者有10个疝囊。93.06%（67/72）的斜疝疝囊的腹股沟管内环扩大，直疝及股疝疝囊的腹股沟管内环均正常；斜疝及直疝疝囊均无股三角填塞，股疝疝囊均股三角填塞；斜疝及股疝疝囊均无侧新月征，82.61%（19/23）的直疝疝囊具有侧新月征；斜疝及直疝疝囊位于腹股沟韧带的前方，股疝疝囊均位于腹股沟韧带的后方；90.28%（65/72）的斜疝疝囊壁位于腹壁下动脉的外侧，直疝疝囊壁位于腹壁下动脉的内侧，股疝疝囊壁位于腹壁下动脉的后下方。 结论多层螺旋CT检查有助于腹股沟疝的诊断，与临床对腹股沟区解剖结构的了解相结合，对腹股沟直疝、斜疝及股疝的分型具有重要价值。     

Double switch operation (Senning and Rastelli operation) with left atrial augumentation by in situ autologous pericardium: a case report]

A 23-month-old female infant with situs solitus, atrioventricular and ventriculoarterial discordance, pulmonary atresia, ventricular septal defect, who had received modfied right Blalock-Taussig shunt (4 mm Gore-Tex tube) at the age of 2 months, was carried out double switch operation with left atrial augumentation by in situ autologous pericardium. The spatial position of the heart was mesocardia. The systemic right ventricular end-diastolic volume was 100% of normal, and the pulmonic left ventricular end-diastolic volume was 105% of normal. Atrioventricular valvular regurgitation was not found. Postoperative course was uneventful. On the 28th postoperative day,she discharged from hospital. The disadvantage of double switch operation is difficulty of atrial switch procedure, because most patients have a small atrium due to dextrocardia or mesocardia. For the purpose of atrial augumentation without artificial materials, our modified Senning procedure is useful. But longer follow-up is necessary to determine whether this technique is indeed beneficial.     

Limitations of arterial pulse pressure variation and left ventricular stroke volume variation in estimating cardiac pre-load during open heart surgery

BACKGROUND: In addition to their well-known ability to predict fluid responsiveness, functional pre-load parameters, such as the left ventricular stroke volume variation (SVV) and pulse pressure variation (PPV), have been proposed to allow real-time monitoring of cardiac pre-load. SVV and PPV result from complex heart-lung interactions during mechanical ventilation. It was hypothesized that, under open-chest conditions, when cyclic changes in pleural pressures during positive-pressure ventilation are less pronounced, functional pre-load indicators may be deceptive in the estimation of ventricular pre-load. METHODS: Forty-five patients undergoing coronary artery bypass grafting participated in this prospective, observational study. PPV and SVV were assessed by pulse contour analysis. The thermodilution technique was used to measure the stroke volume index and global and right ventricular end-diastolic volume index. Trans-oesophageal echocardiography was used to determine the left ventricular end-diastolic area index. All parameters were assessed before and after sternotomy, and, in addition, after weaning from cardiopulmonary bypass before and after chest closure (pericardium left open). Patients were ventilated with constant tidal volumes (8 +/- 2 ml/kg) throughout the study period using pressure control. RESULTS: SVV and PPV decreased after sternotomy and increased after chest closure. However, these changes could not be related to concomitant changes in the ventricular pre-load. The stroke volume index was correlated with SVV and PPV in closed-chest conditions only, whereas volumetric indices reflected cardiac pre-load in both closed- and open-chest conditions. SVV and PPV were correlated with left and right ventricular pre-load in closed-chest-closed-pericardium conditions only (with the best correlation found for the right ventricular end-diastolic volume index). CONCLUSIONS: SVV and PPV may be misleading when estimating cardiac pre-load during open heart surgery.     

Dreidimensionale biomechanische Untersuchung eines neuen flexiblen lumbalen Bandscheibenimplantats

The aim of this study was to determine the significance of a new artificial nucleus implant for lumbar discs (polymethyl siloxane polymer, DR-PMSO) with special regard to the biomechanical properties of the spinal motion segment. The lumbar segments L1/L2 and L4/L5 were harvested from six calf cadavers. The segments were fixed on a special device mounted on a three-dimensional testing machine. Physiological load with a maximum of 7 Nm was applied in flexion/extension, right and left lateral bending, and right and left torsion. The movement of the measuring point (center of L1 and L4) was registered along three axes (sagittal, frontal, and vertical). Three cycles of measurements were performed on all specimens: (1) intact segment, (2) segment after nucleotomy, and (3) segment with PMSO. There was a statistically significant (p=0.0313) increase in segmental mobility in all directions after nucleotomy with an increased mobility of the segment up to 30% for rotation and 50% for translation. After introduction of the PMSO implant, segmental mobility for all movement directions was restored with no statistically significant difference from the intact situation before nucleotomy. The disc material was found to be noncytotoxic according to current ISO 10993 standards.     

A case of ruptured aneurysm of the sinus of Valsalva with bacterial endocarditis

A 21-year-old male with ruptured aneurysm of sinus of Valsalva caused by bacterial endocarditis is presented. The patient complained of palpitation and a attack of fever. Continuous murmur was heard with a thrill at the third intercostal space of the left sternal border. On plain chest x-ray film pulmonary congestion and increase in pulmonary flow were observed. Cardiac catheterization showed step up of oxygen contents at the level of right ventricle and left to right shunt of 36.5%. Aortography demonstrated the aneurysm of the sinus of Valsalva ruptured to right ventricle. The operation was performed by right ventricular approach. Aneurysmal sac was resected and its orifice was closed with mattress sutures. Bacteriological examination at the time of operation revealed Staphylococcus aureus. Postoperative course was uneventful.     

Measurements of alveolar sac diameters by incident-light photomicrography. Effects of positive-pressure respiration

Quantitative and morphological studies by incident-light photomicrography were made in vivo on alveolar sacs and alveoli of Sprague-Dawley rats. The lung was exposed for study through a right or left thoracotomy. Ventilatory support was provided by a positive-pressure respirator delivering a tidal volume of 5 ml. at 40 cycles per minute and 15 cm. H₂O pressure. The mean diameter of 100 sacs at peak inspiration was 66.6 ± 10.7 μ and was 59.3 ± 4.5 μ at end-expiration, a decrease of 11%. Corresponding mean diameters of 10 alveoli were 27.8 μ and 25.7 μ, a decrease of 7.2%. Sacs were partitioned internally by smoothly contoured septa, low ridges, or folds into subsidiary compartments of complex shapes and variable sizes. The microscopical morphology of all structures studied was affected greatly by respiratory excursions of the lung. Variations in alveolar sac morphology may affect respiratory gas exchange in vivo.     

Concept of Totally Biological Internal Coating for Newly Shaped Artificial Ventricles

Abstract: The need for improvement of artificial heart biocompatibility led to the design of new artificial ventricles with biological internal coating and new shapes and sizes. The internal coating of these artificial ventricles is made of a molded single-piece, glutaraldehyde-preserved pericardial sac. The pericardial sac was obtained from the entire intact pericardium of Yucatan pigs. The pericardium was molded and fixed in a 0.6% glutaraldehyde buffered solution and specifically cut to obtain a truncated egg shaped sac with specific dimensions and 110 cm total volume. Two pericardial sacs associated with one another form a biventricular device to create a new orthotopic total artificial heart. The compliance of this device to rules pertaining to total artificial heart concept and implantation makes plausible a new total artificial heart which given its biomaterials, shape, and dimensions can provide optimal anatomical, biological, and hemodynamic conditions.     

Mechanical support of the circulation followed by cardiac transplantation

Improvements in both mechanical circulatory support devices and immune therapy promise a wider use of sequential mechanical support as a bridge to orthotopic cardiac transplantation. The intra-aortic balloon pump, the left and right ventricular assist pumps, and the pneumatic artificial heart represent the range of devices capable of keeping a patient alive who is awaiting a donor organ. The major difficulty in using circulatory support devices is infection, which is caused by their required percutaneous tubes. We report here our experiences with mechanical circulatory support devices as a bridge to cardiac transplantation. In a series of 31 consecutive transplant procedures, six patients have required preoperative mechanical circulatory support. The intra-aortic balloon pump was used in two patients for 2 and 14 days, respectively, before transplantation. Both patients are well 10 and 11 months after the transplant procedure. Two patients required the left ventricular assist device for 11 and 21 days and are alive 3 weeks and 8 months, respectively, after transplantation. One patient was supported by the pneumatic artificial heart for 10 days before a donor heart became available but died of septic shock 17 days after transplantation. A second patient received a pneumatic artificial heart 7 days after transplantation when the heart transplant failed. He has been in stable condition for 45 days but is recovering from renal failure. Our early experiences indicate that either partial or total mechanical support as a bridge to transplantation is successful if overwhelming sepsis or renal failure can be avoided.     

聚对二氧环己酮缝线编织构建仿生型人工小口径血管支架的实验研究

目的 探讨以聚对二氧环己酮(polydioxanone,PDS)缝线编织网管为中间弹力层,构建仿生型三层小口径血管支架的可行性,并检测其生物力学性能.方法 采用7-0 PDS缝线编织内径为4mm的网管,比较不同的编织结构和编织工艺角对PDS网管生物力学性能的影响.将小肠黏膜下基质包被于PDS支架外表面,以8-0 PDS缝线沿纵轴连续缝合固定,支架内层覆以复合硫酸软骨素共混胶原,真空冷冻干燥.检测血管支架的生物力学性能(爆破压力、抗拉伸能力、顺应性等),并与犬颈总动脉进行比较.方果 选择65°的编织工艺角编织内径为4 mm规则结构的网管,长度为3～5 cm;所制备的人工血管的爆破压为(43,50±8.30)kPa,断裂强度为(19.10±1.56)N,应变率为(42.88±3.16)%,径向顺应性为(5.96±0.87)%/100 mm Hg.方论 以PDS编织网管作为中间弹力层构建的复合型人工小血管支架力学性能满意,可以满足动物体内移植试验的需要.     

Biomechanical properties of synthetic lumbar intervertebral disk implants

AIM: The aim of this study was to determine the influence of two different artificial nucleus implants for lumbar discs on the biomechanical properties of the spinal motion segment. METHODS: From 7 calf spines, the lumbar segments L2/3 and L4/5 were harvested, the lamina and the muscles were removed with care to preserve the anterior and posterior longitudinal ligament. The segments were fixed on a special testing device mounted in an universal testing machine (Zwick, Ulm, Germany). Physiological load with a maximum of 7 Nm was applied in flexion/extension, right and left side bending, and right torsion. Three cycles of measurement were performed in all specimen: a) the intact segment, b) segment after nucleotomy, c) 6 segment with 2 PDN devices (Ray Medica) and 8 segments with an autopolymerized polymer. RESULTS: There was a statistically significant (p = 0.0078/p = 0.0313) increase in segmental mobility in all directions after nucleotomy. After introduction of two PDN implants as well as the polymer implant, there was a restoration of segmental mobility for all movement directions with no statistically significant difference (p > 0.05) compared to the intact situation before nucleotomy.     

Application of a Lumped Parameter Model to Study the Feasibility of Simultaneous Implantation of a Continuous Flow Ventricular Assist Device (VAD) and a Pulsatile Flow VAD in BIVAD Patients

The aim of this work is to develop and test a lumped parameter model of the cardiovascular system to simulate the simultaneous use of pulsatile (P) and continuous flow (C) ventricular assist devices (VADs) on the same patient. Echocardiographic and hemodynamic data of five pediatric patients undergoing VAD implantation were retrospectively collected and used to simulate the patients' baseline condition with the numerical model. Once the baseline hemodynamic was reproduced for each patient, the following assistance modalities were simulated: (a) CVAD assisting the right ventricle and PVAD assisting the left ventricle (RCF + LPF), (b) CVAD assisting the left ventricle and PVAD assisting the right ventricle (LCF + RPF). The numerical model can well reproduce patients’ baseline. The cardiac output increases in both assisted configurations (RCF + LPF: +17%, LCF + RPF: +21%, P = ns), left (right) ventricular volumes decrease more evidently in the configuration LCF + RPF (RCF + LPF), left (right) atrial pressure decreases in the LCF + RPF (RCF + LPF) modality. The pulmonary arterial pressure slightly decreases in the configuration LCF + RPF and it increases with RCF + LPF. Left and right ventricular external work increases in both configurations probably because of the total cardiac output increment. However, left and right artero‐ventricular coupling improves especially in the LCF + RPF (?36% for the left ventricle and ?21% for the right ventricle, P = ns). The pulsatility index decreases by 8.5% in the configuration LCF + RPF and increases by 6.4% with RCF + LPF (P = 0.0001). A numerical model could be useful to tailor on patients the choice of the VAD that could be implanted to improve the hemodynamic benefits. Moreover, a model could permit to simulate extreme physiological conditions and innovative configurations, as the implantation of both CVAD and PVAD on the same patient.