Outcomes of a Novel Magnetically Levitated LVAD: a Multicenter Analysis
- Conditions
- Heart Failure
- Interventions
- Device: CH-VAD
- Registration Number
- NCT06596499
- Lead Sponsor
- Beijing Anzhen Hospital
- Brief Summary
This multicenter, retrospective cohort study evaluates the clinical outcomes associated with a novel fully magnetically levitated left ventricular assist device (LVAD) in patients with advanced heart failure. Data were collected from seven medical centers in China, involving patients who received the CH-VAD device between June 1, 2022, and June 30, 2024. The study aims to assess short-term and long-term outcomes, including survival, myocardial recovery, and device-related complications.
The CH-VAD is designed with a magnetically levitated rotor to minimize mechanical wear and the risk of thrombosis. Patients included in the study were those with end-stage heart failure, selected based on specific clinical criteria, with the CH-VAD being the primary mechanical circulatory support device. Data were extracted from electronic medical records, including demographic information, clinical characteristics, surgical details, and postoperative outcomes.
Exposure factors analyzed include patient demographics, preoperative conditions, and details of the CH-VAD implantation. The primary endpoints were survival to transplant, myocardial recovery, reoperation to replace the original pump, or heart transplantation within 30 days and at 1 year postoperatively. Secondary outcomes included adverse events such as device thrombosis, stroke, and major bleeding.
Statistical analysis was conducted using Kaplan-Meier survival curves and multivariable regression models to evaluate outcomes. The study was approved by the Institutional Ethics Committee of Anzhen Hospital, with a waiver of informed consent due to its retrospective nature.
This study provides data on the clinical outcomes associated with the CH-VAD, contributing to the understanding of its use in patients with end-stage heart failure.
- Detailed Description
Introduction Heart failure (HF) represents a complex pathophysiological manifestation that emerges when cardiovascular diseases progress to their end stages, rendering the heart incapable of maintaining its function. The incidence of HF is continually rising globally, affecting over 60 million people worldwide, with approximately 6.4 million in the end-stage HF category. In China, it is conservatively estimated that there are about 13 million HF patients, including around 1 million in the end-stage. End-stage HF is characterized by persistent symptoms of HF that interfere with daily activities despite maximal medical therapy, leading to repeated hospitalizations. The annual mortality rate for patients at this stage is as high as 50%. Therefore, once end-stage HF occurs, it presents a prolonged and complex course, making treatment difficult and placing a significant burden on public health resources.
Currently, the main treatments for end-stage HF include heart transplantation (HTx) and mechanical circulatory support (MCS). HTx is considered the gold standard treatment for providing optimal survival and quality of life. However, the scarcity of donor hearts and the complexity of immunosuppressive therapy limit its application, with around 6,000 heart transplants performed globally each year, and only about 700 annually in China. MCS devices, such as left ventricular assist devices (LVADs), offer an effective alternative.
LVADs have undergone significant evolution through three generations of blood pumps, including pulsatile, axial flow, and centrifugal pumps (hydrodynamic levitation, magneto-hydrodynamic levitation, and fully magnetically levitated). They have become a critical treatment option for end-stage HF. In the United States, approximately 3,000 patients receive LVADs annually, surpassing the number of heart transplants. The U.S. Food and Drug Administration (FDA) has approved implantable LVADs for end-stage HF patients classified as INTERMACS levels 1 to 4, for use as long-term support (destination therapy, DT), as a bridge to transplant (BTT), and as a bridge to recovery (BTR). Over the past five years, LVAD therapy has undergone significant transformation and development internationally. The largest clinical trial to date on LVAD therapy has shown that compared to the HeartMate II, the latest generation centrifugal LVAD, the HeartMate III, significantly reduces the incidence of device thrombosis, stroke, gastrointestinal bleeding, and mortality. Compared to HTx, implantable LVADs have several advantages, such as the absence of the need for a donor heart and the lack of immune rejection, making them a life-saving device for an increasing number of end-stage HF patients.
The application of LVADs in China began relatively late but is currently experiencing rapid development. To date, there have been four officially approved LVADs in China. Among them, the CH-VAD (BrioHealth Solutions) is a novel centrifugal-flow device characterized by its fully magnetically levitated design and compact size. The first-in-man implantation of the CH-VAD took place in 2017 under compassionate use, marking a significant milestone in the application of durable LVADs in China. Following this, a multi-center, single arm clinical trial was conducted, providing data that led to the approval of this device in China in 2021. Thus far, more than 300 patients have been implanted with the technology across China. A single-center study conducted at Fuwai Hospital with 50 consecutive patients revealed promising outcomes and a favorable adverse event profile; however, the findings are limited by the single-center nature of the study and the relatively small sample size.
This multicenter observational study aims to evaluate the clinical efficacy and safety of the CH-VAD in end-stage HF patients when the device is used commercially, providing insights into its safety and effectiveness in real-world applications. This study includes all patients who received CH-VAD implants in a post-market approval setting between June 2022 and June 2024 across seven centers in China.
Methods
1. Device description The CH-VAD pump is a fully magnetically levitated (maglev), centrifugal continuous-flow blood pump. Its motor and maglev components are separated, allowing for optimal use of space within the pump. The pump measures 25 mm thick with a diameter of 47 mm and a weight of 186 grams. the compact size facilitates easier implantation and reduces ventricular distortion. Despite its small dimensions, the device contains a 33 mm impeller with long blades, which allows it to spin at a lower operational speed. This reduces turbulence and blood trauma, and achieves a flatter H-Q curve to enhance hemodynamic responsiveness and pass-through pulsatility.
The device has unique flow paths designed to improve hemocompatibility. A nose cone structure on top of the central post guides the flow to smoothly change direction. A U-shaped secondary flow path has an optimized gap width to minimize turbulence and enhance washout. The speed range of the pump is from 1000 to 4200 rpm and blood flow up to 10 L/min can be delivered. The superior hemocompatibility and flow characteristics have been demonstrated by computational fluid dynamics, bench tests, and animal studies.
The device also features a very narrow (3.3-mm outer diameter) and flexible driveline, which may improve patient comfort and potentially decrease the risk of infection. The system is powered by either two lithium batteries or a single battery plus AC power. Each battery, with a capacity of 5200 mAh, can sustain the system for 6-8 hours and reaches a full charge within 5 hours.
2. Study Design The study protocol was approved by the institutional ethics committee approval of Anzhen Hospital with a waiver of informed consent XX,XX,XX. XX consecutive patients implanted with the CH-VAD between 1 June 2022 and 30 June 2024 across 7 centers in China were included in this retrospective study. This study was initiated and led by Beijing Anzhen Hospital, affiliated with Capital Medical University, and involved six other medical centers from various provinces in China. These centers include Sichuan Provincial People's Hospital in Chengdu, Henan Chest Hospital in Zhengzhou, Shanghai Chest Hospital in Shanghai, Shanghai Zhongshan Hospital in Shanghai, Asia Heart Hospital in Wuhan, and The First Affiliated Hospital of Nanjing Medical University in Nanjing. The study conforms with the Declaration of Helsinki and the ISHLT Ethics statement.
3. Study Population All decisions to undergo surgery came from the multidisciplinary heart failure team including cardiac surgeons, cardiologists, echocardiography specialists, cardiovascular anaesthesiologists, nurses and other specialists. All patients implanted with the CH-VAD as the primary device in a post-market approval setting were included.
4. Data Collection Clinical data collected from electronic clinical records include demographic information, history of presentation, past medical history,, laboratory results, hemodynamic parameters, echocardiography, surgical details, clinical outcomes, adverse events and readmission information.
4.1 Clinical characteristics
The following demographic and clinical characteristics of enrolled participants before the operation will be recorded:
* Sex
* Age
* Height (cm)
* Weight (kg)
* Etiology of heart failure (ischemic cardiomyopathy, dilated cardiomyopathy, other causes)
* Preoperative mechanical circulatory support (ECMO, intra-aortic balloon pump \[IABP\], Impella)
* Risk factors for cardiovascular diseases and comorbidities (stroke, arterial hypertension, diabetes mellitus, atrial fibrillation, ventricular arrhythmia)
* INTERMACS profile
* NYHA
* History of cardiac surgery
* History of cardiac intervention 4.2 Echocardiography Transthoracic echocardiogram (TTE) prior to and after LVAD implantation were performed using commercially available machines. By TTE, the chamber sizes, ventricular function, valve function as well as the device function were reviewed.
4.3 Hemodynamic Parameters
The following hemodynamic parameters prior to and after LVAD implantation (from the last measurements before the operation to the enrollment) will be collected from the medical records if available:
* cardiac output (CO) and cardiac index (CI)
* central venous pressure (CVP)
* pulmonary artery pressures (PAP), systolic, diastolic and mean PAP
* pulmonary capillary wedge pressure (PCWP)
* pulmonary vascular resistance (PVR) 4.4 Laboratory tests
Laboratory tests conducted prior to and after LVAD implantation (from the last measurements before the operation to enrollment) will be collected via electronic medical records. The following tests will be reviewed if available:
* Biochemistry: Sodium, potassium, BUN, creatinine, albumin, bilirubin, liver enzymes
* Hematology: WBC, Hgb, HCT, PLT
* Coagulation: PT and INR
* Cardiac Markers: BNP or NT-proBNP 4.5 Perioperative variables
The following perioperative variables will be collected from the medical records:
* Surgical approach
* Concurrent surgical procedures
* length of ICU stay
* length of hospital stay (LOS)
* total surgery time
* time on the CPB
* time on aortic cross-clamp 4.6 Patient Health Status Patients' heart failure symptoms and signs retrieved from electronic medical records before and after (from discharge to enrollment) the surgery.
* Dyspnea
* Fatigue
* Edema grades (1 to 4)
* Abdominal distension
* Palpitation
* Loss of appetite
* NYHA 4.7 Clinical events and Complications All the clinical events and complications post LVAD implantation to enrollment will be retrieved from medical records and re-adjudicated . Definitions of events as described by the INTERMACS guidelines were employed.
* Hemolysis
* Right heart failure
* Device Failure
* Major bleeding-VAD implantation related bleeding
* Major bleeding-Gastrointestinal bleeding
* Major Bleeding - Other Bleeding
* Major Infection - MCS related infection
* Major infection-Non MCS related infection
* Neurological deficit - ischemic stroke
* Neurological disorder-Hemorrhagic stroke
* Neurological disorder-TIA
* Neurological disorder-Other
* Renal Insufficiency
* Arrhythmia-Atrial
* Arrhythmia-ventricular
* Respiratory failure
* Venous Thromboembolism
* Poor Wound Healing
* Non-Central Nervous System Arterial Thromboembolism
* Hepatic insufficiency
* Hypertension
* Pericardial effusion
* Myocardial infarction
* Aortic valve insufficiency
* Other 4.8 Readmission Readmission events from the discharge of the index hospitalization to enrollment will be collected. The primary cause and duration of each readmission will be collected and analyzed.
5. Outcomes The short-term primary outcome is a composite of survival to transplant, myocardial recovery, reoperation to replace the original pump or heart transplantation within 30 days or during hospitalization.
The long-term primary outcome is a composite of survival to transplant, myocardial recovery, reoperation to replace the original pump or heart transplantation at 1 year postoperatively.
6. Statistical Analysis Data will be represented as frequency distributions and percentages. Values of continuous variables will be expressed as mean ± standard deviation and median with interquartile range, as necessary. Continuous variables will be compared using independent samples t-tests or Wilcoxon rank-sum tests, where appropriate. Categorical variables will be compared by means of χ2 tests or Fischer's exact test, where appropriate. To analyze changes in echocardiographic and hemodynamic parameters and laboratory values, McNemar matched-pairs tests will be used to compare preoperative values to postoperative values after matching individual patient data. For all analyses, a p \< 0.05 will be considered statistically significant. Kaplan-Meier analysis will be used to calculate survival and other time-to-event outcomes. All data will be analyzed using STATA 29 software (IBM, Armonk, NY) and Prism version 9 (GraphPad Software, San Diego, Calif).
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 75
- All patients implanted with the CH-VAD as the primary device in a post-market approval setting were included.
Study & Design
- Study Type
- OBSERVATIONAL
- Study Design
- Not specified
- Arm && Interventions
Group Intervention Description CH-VAD CH-VAD All patients implanted with the CH-VAD as the primary device
- Primary Outcome Measures
Name Time Method short-term primary outcome 30 days The short-term primary outcome is a composite of survival to transplant, myocardial recovery, reoperation to replace the original pump or heart transplantation within 30 days or during hospitalization.
long-term primary outcome 1 year The long-term primary outcome is a composite of survival to transplant, myocardial recovery, reoperation to replace the original pump or heart transplantation at 1 year postoperatively.
- Secondary Outcome Measures
Name Time Method
Trial Locations
- Locations (1)
Beijing Anzhen Hospital, Capital Medical University
🇨🇳Beijing, Beijing, China