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Objective:To investigate the changes in N-terminal pro-B-type natriuretic peptide (NT-proBNP) and its role in predicting major adverse cardiac events (MACEs) in patients with end-stage heart failure (ESHF) before and after implanted a HeartCon left ventricular assist device (LVAD).Methods:The retrospective study included 30 ESHF patients [23 males and 7 females, aged 54.5 (40.8, 60.0) years], who were admitted to TEDA International Cardiovascular Disease Hospital from September 15, 2020 to June 20, 2023 to receive treatment with HeartCon LVAD implantation. Their clinical data were analyzed and NT-proBNP concentrations in their blood samples were measured preoperatively and during the follow-up period. Patients were followed regularly and MACEs, including cardiac death and rehospitalization for right heart failure, were recorded within 6 months of discharge; Logistic regression was used for prognostic analysis, and Receiver Operator Characteristic (ROC) curves were used to assess the adjunctive diagnostic value of NT-proBNP for poor prognosis in LVAD patients. The cut-off values for diagnosing poor prognosis by NT-proBNP were divided into two groups, and survival analysis was performed by Kaplan-Meier and tested by log rank; Cox regression was performed to analyze whether high levels of NT-proBNP at 6 months of follow-up wsa a risk factor for poor prognosis in patients with LVAD.Results:The median preoperative NT-proBNP level in 30 ESHF patients successfully implanted with HeartCon LVADs was 3 251.0 (1 544.5, 6 401.5) pg/ml. It decreased significantly 7 days postoperatively (3 251.0 vs. 1 815.0 pg/ml, P<0.05), and then the decreasing trend slowed. It decreased to 1 182.0 (620.0, 3 385.3) pg/ml on the 90th post-operative day. The preoperative NT-proBNP>3 251.0 pg/ml group had a longer postoperative hospital stay (47 d vs 33 d, Z=-2.138, P=0.032). Multivariate logistic regression analysis, only NT-proBNP at 7 days postoperatively was found to predict poor prognosis in LVAD patients, with an OR of 1.001 ( P=0.01); ROC curves were analyzed for the adjunctive diagnostic value of 7-day postoperative NT-proBNP levels for poor prognosis (cut-off value of 2 083.0 pg/ml), with an AUC of 0.833 ( P=0.002); The Kaplan-Meier survival analysis showed that the time to MACEs within 6 months was significantly shorter in the group with NT-proBNP>2 083.0 pg/mL on postoperative day 7 than in the group with NT-proBNP≤2 083.0 pg/ml (3.538±0.689 vs. 5.471±0.323 months, P=0.004); Cox regression analysis showed that the risk of MACEs was 4.25 times higher in the 7-day postoperative NT-proBNP>2 083.0 pg/ml group than in the NT-proBNP≤2 083.0 pg/ml group ( HR=4.25, P=0.035). Conclusions:The higher the preoperative NT-proBNP level, the longer the postoperative hospital stay in HeartCon LVAD patients. NT-proBNP levels decrease most significantly on postoperative day 7 and is a risk factor for MACEs. It may be used as a prognostic predictor in ESHF patients with implanted LVADs.

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Objective:To investigate the clinical characteristics and prognosis of patients with left ventricular assist device (LVAD) implantation during the perioperative period.Methods:This retrospective study included 14 patients with end-stage heart failure who underwent LVAD implantation in the department of intensive care medicine of Nanjing Hospital Affiliated to Nanjing Medical University from February 2022 to March 2023, including 12 males and 2 females patients, the mean age was (57.6±9.8)years old. All patients were implanted with Corheart 6 implantable left ventricular assist system, did not use other mechanical assisted circulatory devices. The clinical data of enrolled patients were collected, and the clinical characteristics and prognosis during ICU treatment were analyzed.Results:Dilated cardiomyopathy (DCM) was the most common primary cause of heart failure. The results of transthoracic echocardiography showed that the left ventricular ejection fraction (0.297±0.074 vs. 0.238±0.064, P=0.031) of patients was significantly increased, while the left ventricular end diastolic diameter[69.0(65.8, 74.3)mm vs. 76.5(72.8, 83.0)mm, P=0.003]and systolic end systolic diameter[61.5(53.7, 65.3)mm vs. 68.3(63.8, 71.9)mm, P=0.005]were significantly decreased post LVAD implantation as compared to before LVAD implantation. Within one week after implantation, there was no significant difference in LVAD rotational speed, flow rate, and pulsation index ( P>0.05). During ICU treatment, dobutamine (13 cases) was the most commonly used vasoactive agent. 9 patients used phosphodiesterase Ⅲ inhibitors for perioperative pulmonary hypertension. Targeted management of volume and pressure indicators was conducted for enrolled patients to prevent postoperative right heart failure and to reduce right heart burden. Within 72 hours after LVAD implantation, the average pulmonary artery pressure of patients was 24 (22, 26) mmHg to 26 (21, 28)mmHg (1 mmHg=0.133 kPa), while the fluid balance was(-581±778)ml to(-1 209±1 134)ml. All enrolled patients survived to 28 days after LVAD implantation. The length of stay in the ICU was (8.0±1.8) days and the total length of hospital stay was 33 (29, 41)days, while the time of mechanical ventilation was 8 (5, 28)h. Conclusion:LVAD implantation can help improve left ventricular systolic function, prolong survival time so as to serve as an important means of terminal treatment or bridging therapy for heart transplantation of patients with end-stage heart failure. To strengthen the perioperative hemodynamic regulation and maintain the cardiac function of patients with LVAD implantation is the important purposes of ICU postoperative management.

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Objectives:To investigate the safety and efficacy of concomitant mitral valvuloplasty(MVP)and implantation of domestic third-generation magnetically levitated Corheart 6 left ventricular assist device(LVAD). Methods:Clinical data of 13 end-stage heart failure patients who underwent Corheart 6 LVAD implantation and MVP at Central China Fuwai Hospital of Zhengzhou University from October 2021 to March 2023 were retrospectively analyzed.Mortality and complication events during hospitalization and at follow-up were collected,and changes in myocardial injury biomarkers,renal function,hemodynamics,and echocardiographic indices were observed. Results:There were no perioperative deaths and no MVP-related complications in these patients.During a mean follow-up of(14.2±5.6)months,2 patients died due to COVID-19 pneumonia and cardiac arrest respectively,11 cases(84.6%)survived.There were no recurrences of moderate-to-severe mitral regurgitation in the survived patients.Compared with preoperative value,higher cardiac output,lower central venous pressure,pulmonary artery systolic pressure(PASP),and mean pulmonary artery pressure(PAMP)were evidenced at 24 h and 72 h postoperatively,estimated glomerular filtration rate was also reduced at 1 week post operation(all P<0.010).High-sensitive troponin T level was significantly increased at 1 week post operation and then reduced at 1 month post operation,but still not returned to pre-operative level([125.5±281.9]pg/ml at baseline,[1 295.6±654.6]pg/ml at 1 week post operation and[278.0±300.5]pg/ml at 1 month post operation).Echocardiography showed that compared with preoperative period,the left ventricular ejection fraction tended to be higher at 1 and 6 months postoperatively(both P>0.017),whereas left ventricular end-diastolic dimension,PASP,and PAMP were significantly reduced(all P<0.010). Conclusions:Domestic third-generation magnetically levitated Corheart 6 LVAD implantation with concomitant MVP is safe and feasible,there is no recurrence of moderate-to-severe mitral regurgitation,a significant reduction in pulmonary artery pressure,and significant hemodynamic improvement in early to mid-term postoperatively are observed in survived patients.

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Resumen La falla cardiaca avanzada es cada vez más frecuente. En esta población, los dispositivos de asistencia ventricular izquierda han emergido en los últimos treinta años como una terapia puente al trasplante o definitiva en aquellos con contraindicación para este. Estos dispositivos son de flujo continuo, contrario a la fisiología hemodinámica normal, fenómeno que conlleva una serie de complicaciones asociadas a la interacción entre el dispositivo y el paciente, la cual se conoce como "hemocompatibilidad". Una de sus implicaciones es la ausencia de pulso central y la necesidad de toma de presión arterial a través de métodos poco frecuentes, como el Doppler. Las diferentes complicaciones asociadas a este son frecuentes y pueden reunirse bajo la mnemotecnia A2B2C2D2, incluyendo aquellas específicas y relacionadas con el dispositivo. Es necesario reconocer cada una de estas para el diagnóstico y tratamiento tempranos y oportunos, incluyendo el inicio precoz de maniobras de reanimación en caso de estar indicado, para impactar la supervivencia de estos pacientes.

Abstract Advanced heart failure is becoming more frequent and, in this population, left ventricular assist devices have emerged in the last thirty years as bridge-to-transplant or destination therapy for those with a contraindication for transplant. These devices are continuous flow, contrary to normal hemodynamic physiology, which leads to associated complications with the interaction between the device and the patient, a phenomenon known as "haemocompatibility". One of its implications is the absence of a central pulse and the need to measure blood pressure through infrequent methods such as Doppler. Various complications are frequently associated with this and can be grouped under the mnemonic A2B2C2D2, including those specific and related to the device. Each of these must be recognized for early and prompt diagnosis and treatment , including prompt cardiopulmonary resuscitation, if indicated, to impact the survival of these patients.

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The field of pediatric heart failure is evolving, and the patient population is growing as survival after complex congenital heart surgeries is improving. Mechanical circulatory support and extracorporeal respiratory support in critically ill children has progressed to a mainstay rescue modality in pediatric intensive care medicine. The need for mechanical circulatory support is growing, since the number of organ donors does not meet the necessity. This article aims to review the current state of available mechanical circulatory and respiratory support systems in acute care pediatrics, with an emphasis on the literature discussing the challenges associated with these complex support modalities

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

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

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Objective To investigate the effect of left ventricular assist device (LVAD) and aortic graft angle on hemodynamics of aortic valve. Methods Three models of aorta and aortic valve with 45°, 60° and 90° anastomosis angles between LVAD and aorta were constructed, and an in vitro pulsating table was built for in vitro experiments. Using particle image velocimetry (PIV) system, three moments in the cardiac cycle ( T1 systolic peak, T rapid closure, T3 diastolic peak), were selected to study the hemodynamic state of aortic valve. Results Velocity vector, vorticity and viscous shear stress were used to evaluate the effect of LVAD anastomosis angle on hemodynamics of aortic valve. During the period of rapid valve closure, with the increase of graft angle, the blood flow velocity near the valve wall, the average vorticity and the maximum viscous shear stress all increased. Conclusions When the graft angle is lower, the impact velocity of blood on the valve is smaller, and the shear force on the valve decreases, so that the valve is in a better hemodynamic environment. This study provides references for the selection of anastomotic angles in clinical operations.

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Objective:To analyze and evaluate the safety and efficacy of a Chinese domestically manufactured Heart Con-type implantable third-generation magnetic and hydrodynamic levitation left ventricular assist device(LVAD) for the treatment of end-stage heart failure(ESHF), by reporting the results of eleven-center clinical trial on 50 cases.Methods:This study was a multicenter clinical trial, designed by means of prospective, multicenter and single-group target value. 50 subjects with ESHF were competitively enrolled and treated with HeartCon as the LVAD in eleven centers. The primary efficacy measure was survival, defined as either the subjects experiencing the transition to heart transplantation(HT) or myocardial recovery assisted by the device within 90 days, or as successfully assisted by the LVAD for full 90 days after implantation. The target survival rate was 60%, other observations included implantation success rate, mortality, pump failure needing replacement or emergency heart transplantation.Results:All enrolled 50 patients received LVAD implantation successfully, 46 survived with the pump for 90 days, 1 patient transitioned to heart transplantation, and 3 patients experienced pump thrombosis, within which 2 patients underwent pump replacement and continued to live with the pump for 90 days, and the other one received emergency heart transplantation. There were no dropout subjects. The survival rate at full 90 days after HeartCon implantation was 100%. The survival rates with pump in the full set analysis and the protocol set analysis were 96.00% and 95.92% respectively, which were higher than the target value of 60%. The differences were both statistically significant( P<0.05). Conclusion:The results of the multicenter clinical trial with the largest sample size in China using domestically manufactured third-generation LVAD has demonstrated that, HeartCon is a safe and effective LVAD to treat ESHF patients.

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@#Implantable left ventricular assist device (LVAD) has become an essential treatment for end-stage heart failure, and its effect has been continuously improved. In the world, magnetic levitation LVAD has become mainstream and is increasingly used as a destination treatment. China has also entered the era of ventricular assist device. The continuous improvement of the ventricular assist device will further improve the treatment effect. This article reviews the current situation and development trend of LVAD treatment in China and abroad.

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Objective:To investigate and summarize the early management experience of 22 patients with end-stage heart failure(ESHF) who underwent left ventricular assist device(LVAD) implantation in an intensive care unit(ICU) in a single center.Methods:Data of 22 patients with ESHF treated with LVAD in the ICU of TEDA International Cardiovascular Hospital from September 2020 to August 2022 were retrospectively analyzed. There were 16 males and 6 females, aged from 20 to 67 years old, with a mean age of(51.0±13.3)years old. There were 21 cases with dilated cardiomyopathy, 1 case with ischemic cardiomyopathy, 6 cases with tricuspid regurgitation, 1 case with intra-aortic balloon pump for cardiogenic shock, and 5 cases with cardiac resynchronization therapy for arrhythmia. After the operation, all patients received restricted fluid therapy, a " stepwise" anticoagulation strategy, and strict blood pressure management. The postoperative complications and treatment process were reviewed, the treatment and management experience were summarized, and the prognosis of the patients was statistically analyzed.Results:All 22 patients survived within 90 days after surgery, and 21 patients(95.5%) recovered well, the pump works fine and there was no hemolysis and thrombosis of LVAD. Major complications included: 1 case of severe pneumonia(4.5%), 2 cases of pericardial tamponade(9.1%), 1 case of intracerebral hemorrhage(4.5%), 1 case of mediastinal infection(4.5%), 5 cases of positive occult blood in gastric juice(22.7%), no cases of right ventricular failure、aortic insufficiency and cerebral infarction. The duration of postoperative mechanical ventilation was 17(8.5, 51.5) h, and the ICU stay was 14(10, 27) days.Conclusion:LVAD is another effective treatment for patients with ESHF in addition to heart transplantation. Good postoperative blood pressure control, " stepwise" anticoagulation strategy and " restrictive" fluid management can reduce postoperative complications in the early phase of post-operation, which is crucial for the prognosis of patients with LVAD.

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Extracorporeal membrane oxygenation (ECMO) could pump the blood from human veins to the outside of the body, oxygenate the red blood cells in an artificial environment and then return them back into the body. ECMO could replace the heart and lungs to complete gas exchange and systemic blood perfusion in patients with severe cardiopulmonary insufficiency, which also plays an important role in the field of heart transplantation. Besides circulatory support treatment after heart transplantation, ECMO may also be used to prolong the waiting time for heart transplantation in patients with respiratory and circulatory failure before operation, as a bridging therapy for heart transplantation. However, at present, the application of ECMO in pediatric heart transplantation still exist challenges, such as high perioperative mortality and difficulty in determining the timing of treatment, etc. In this article, the development history of ECMO application in pediatric heart transplantation, use of ECMO before and after pediatric heart transplantation, ECMO-related complications in children, and application of ventricular assist device (VAD) in pediatric heart transplantation were briefly reviewed, aiming to provide reference for promoting the application of ECMO in pediatric heart transplantation.

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Pediatric heart transplantation is the standard treatment for children complicated with refractory heart failure which is difficult to be treated by conventional surgery or drugs. At present, an increasing quantity of pediatric heart transplantation is being performed worldwide, whereas relevant experience is still lacking in China. In recent 10 years, significant progress has been achieved in pediatric heart transplantation. On one hand, the number of pediatric heart transplantation has been increased year by year. On the other hand, ABO-incompatible heart transplantation, application of ventricular assist device in children, and recipient-donor weight mismatch transplantation have been widely employed to resolve the shortage of donor heart in pediatric heart transplantation. However, relevant experience of pediatric heart transplantation is lacking in China, especially in understanding the indications of pediatric heart transplantation and the application of specific strategies for pediatric heart transplantation, etc. In this article, the development history, advances in therapeutic strategy and clinical prognosis of pediatric heart transplantation were reviewed.

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At present, heart transplantation is the most effective treatment for end-stage heart failure. Nevertheless, the shortage of donors is becoming an increasingly severe challenge. In recent years, rapid development of mechanical circulatory support technologies has provided multiple therapeutic options for patients with end-stage heart failure. As an important mechanical circulatory support device, ventricular assist device (VAD) are divided into durable VAD (dVAD) and temporary VAD (tVAD) according to the duration of assistance. dVAD shows application potential in bridging heart transplantation, destination therapy and bridge to decision. With technological progress and experience accumulation in clinical application, VAD is evolving towards the direction of more biocompatible, lighter, more bionic and intelligent. In this article, the development of VAD, application status at home and abroad and the overall application of VAD in our hospital were reviewed, aiming to provide reference for promoting the clinical application of VAD in China.

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Left ventricular assist devices (LVAD) are increasingly used in patients with end-stage heart failure. Devices significantly affect patient physiology, leading to unique complications and different drug treatment strategies. The pharmacist is an integral part of a multidisciplinary team and has the responsibility to help patients use their medicines safely and appropriately. It is important to anticipate common postoperative complications and prepare appropriate treatments for them. This article reviews the current guidelines and research literature on the management of pharmacotherapy in patients with LVAD, integrates clinical research practice, summarizes the medication relevant experience and presents a review.

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We present a case of acute respiratory distress syndrome (ARDS) secondary to COVID?19 who required venovenous extracorporeal membrane oxygenation (V?V ECMO). Initially, a right ventricular assist device (RVAD), the ProtekDuo with an oxygenator, was placed in an outside heart center and the patient was transferred to us for ECMO management. Due to severe hypoxia, the configuration was later modified, and a 25 Fr femoral drainage cannula was inserted for venous drainage only. The arterial return tubing was spliced and using a Y?connector, arterialized blood was returned through both limbs of the ProtekDuo resulting in a significantly increased oxygenation and flow.

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Objective To study CH-VAD blood pump developed by CH Biomedical Inc., a method for estimating the real-time flow of blood pump was established by using the voltage, current, speed, duty cycle, and fluid viscosity as the input data. Methods The blood pump system was disassembled into two modules, the motor and the centrifugal pump. Firstly, the output torque of the motor was calculated according to the voltage, current, speed and duty cycle of the motor, then the relationship between flow and torque at different speeds and viscosities was tested through experiments, and a fitting model was established based on the experimental data. Results The fit goodness of Pump 1 and Pump 2 reached 0.982 6 and 0.982 9,respectively. The fitting parameters were used for verification. When the viscosity changed, the root mean square error for the estimated flow of Pump 1 and Pump 2 was 0.260 and 0.274 L/min, respectively. The fitting parameters and estimated results of the two blood pumps were in good agreement. The flow estimation method could follow the actual flow waveform in real time, and the accuracy of the estimated average flow was not affected by the pulsation. Conclusions The flow estimation method proposed in this paper is suitable for CH-VAD blood pumps. It can accurately estimate the flow of blood pumps in the range of speed 1 600-3 600 r/min, flow 0.4-8 L/min, viscosity 1.2-5 mPa·s, and can follow the flow waveform well under pulsating conditions.

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@#Although heart transplantation remains to be the optimal treatment for advanced heart failure, its use has been largely limited due to shortage of available donor organs. Over the past two decades, left ventricular assist device (LVAD) has been significantly modified in size, durability and hemocompatibility. In addition to the bridge to transplantation, LVAD has become an attractive alternative to heart transplantation for end-stage heart failure as destination therapy for unsuitable candidates. Although the performance of LVAD has been improving greatly in recent years, there are still great challenges in the management of device complications and low quality of life after implantation. This review will summarize the types of LVAD, indications for implantation, postoperative management and adverse events.

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Objective:To investigate and evaluate the efficacy of HeartCon left ventricular assist device (LVAD) in the treatment of adult patients with end-stage heart failure (ESHF).Methods:A prospective and observational study was conducted. Patients with ESHF who underwent LVAD implantation in the department of cardiac surgery of Teda International Cardiovascular Hospital from September 2020 to August 2021 were selected. The left ventricular end-diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF), New York Heart Association (NYHA) classification, N-terminal pro-B type natriuretic peptide (NT-proBNP), and six minute walk distance (6MWD) before operation and 90 days after operation were compared. The incidence of equipment failures and major adverse events within 90 days after operation were recorded.Results:A total of 20 patients with ESHF were included, with 15 males and 5 females. Patients' age ranged from 20 to 67 years old, with an average of (50.2±13.6) years old. The range of body weight was 49.8-106.1 kg, with an average of (67.9±15.5) kg, and the body surface area (BSA) was from 1.49 to 2.32 m 2, with an average of (17.6±0.22) m 2. The operation process of all the patients were successful. The length of hospital stay ranged from 33 to 90 days, and the average was 56.0 (42.8, 75.0) days. Complications within 90 days after operation as follows, 2 cases with pericardial tamponade (10%), 1 case with cerebral hemorrhage (5%), 1 case with mediastinum infection (5%), 3 cases with acute renal injury (AKI, 15%), 5 cases with gastrointestinal bleeding (25%). There were no mechanical failure of LVAD and hemolysis events, right ventricular failure (RVF), cerebral infarction and death occurred. Compared with preoperative, the LVEDD significantly decreased (mm: 67.50±13.98 vs. 77.40±9.73), LVEF significantly increased (%: 34.80±9.76 vs. 22.70±5.62), NT-proBNP significantly decreased (ng/L: 2 028.65±1 752.05 vs. 4 796.45±4 355.40), 6MWD significantly increased (m: 385.20±144.12 vs. 85.81±63.50) at 90 days after operation, and the differences were statistically significant (all P < 0.05). 18 cases (90%) of the 20 patients reached NYHA classification Ⅰ and 2 cases (10%) reached NYHA classification Ⅱ, which were significantly improved compared with those before surgery (all patients' NYHA classification were Ⅳ before surgery). Conclusion:HeartCon LVAD can effectively improve the life quality of patients with ESHF, which has been proved safe and effective in clinical trials, but its long-term effects and complications need further observation and study.

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The implantation of biventricular assist device (BiVAD) is more challenging than that of left ventricular assist device for the interaction in the process of multiple input and output. Besides, ventricular assist device (VAD) often runs in constant speed (CS) mode in clinical use and thus BiVAD also faces the problems of low pulsation and imbalance of blood volume between systemic circulation and pulmonary circulation. In this paper, a delay assist mode for a VAD by shortening the support time of VAD was put forward. Then, the effect of the delay mode on cardiac output, pulsation and the function of the aortic valve was observed by numerical method and the rules of hemodynamics were revealed. The research showed that compared with VAD supported in CS mode, the VAD using delay mode in systolic and diastolic period proposed in this paper could meet the demand of cardiac output perfusion and restore the function of the arterial valves. The open ratio of aortic valve (AV) and pulmonary valve (PV) increased with the time set in delay mode, and the blood through the AV/PV helped to balance the left and the right cardiac volume. Besides, delay mode also improved the pulsation index of arterial blood flow, which is conducive to the recovery of the ventricular pulse function of patients.

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Objective:To evaluate the clinical value of intraoperative transesophageal echocardiography (TEE) in monitoring left ventricular assist device (LVAD) implantation.Methods:Between March 2019 and November 2021, 23 consecutive patients from TEDA International Cardiovascular Hospital, including 21 cases with dilated cardiomyopathy, 1 case with myocardial noncompaction and 1 case with ischemic cardiomyopathy, underwent HeartCon blood pump, a type of third generation LVAD implantation for severe heart failure. TEE was preformed in all cases before and after cardiopulmonary bypass. The dimensions of left-sided and right-sided cardiac chamber, ventricular function, de-airing, interventricular septal position, inlet cannulae position and the function of device were observed and recorded during LVAD implantation. Paired t test was used for statistical analysis of left-sided and right-sided heart parameters in pre- and post-operative measurements. Results:The left heart was dilated significantly and coexistent with right heart enlargement in some degree before LVAD implantation in total 23 cases. More than moderate mitral regurgitation (MR) in 16 cases and less than moderate MR in 7 cases were present. Mild or trace aortic regurgitation (AR) existed in 13 cases. More than moderate tricuspid regurgitation (TR) in 4 cases and less than moderate TR in 16 cases were observed. Left atrial appendage thrombosis was detected in 2 cases. After LVAD implantation, TEE revealed that the left ventricular end-diastolic diameter reduced significantly (42 mm/m 2 vs 32.8 mm/m 2, P<0.05) and left ventricular ejection fraction increased accordingly (22.2% vs 34.0%, P<0.05). There were no significant differences in right ventricular diameter and fractional area change between pre- and post-operative findings(all P>0.05). The ratio of left ventricular inner diameter to right ventricular inner diameter (2.09 vs 1.69, P<0.05) decreased in total 23 cases after LVAD implantation.Interventricular septal position became neutral position instead of pre-oprative rightward position. The severity of MR decreased in varying degrees in total 23 cases after LVAD implantation. All patients underwent tricuspid valvuloplasty with residual mild regurgitation in 8 cases. Conclusions:HeartCon blood pump can effectively unload the left ventricle with sufficient cardiac output in patients with severe congestive heart failure. TEE plays a major role in the clinical decision making during LVAD implantation, which can evaluate pre-operative cardiac abnormalities, intra-operative air embolism, inlet cannulae position, cannulas patency and cardiac function, especially blood volume status and the balance between double ventricles, which is critical for optimal functioning of the device.