Related Experiment Videos
Current status of artificial hearts and ventricular assist devices
Insights
Mechanical circulatory support devices offer alternatives for refractory heart failure patients when heart transplantation is not feasible. Early implantation of these devices is crucial for improved outcomes in end-stage heart failure.
Area of Science:
- Cardiology
- Biomedical Engineering
- Medical Devices
Background:
- Refractory heart failure management options are limited, with heart transplantation facing donor organ scarcity.
- Mechanical circulatory support (MCS) devices have been developed to address this gap.
- Existing MCS devices vary in design, power, and support duration.
Purpose of the Study:
- To review current approaches for refractory heart failure.
- To categorize available mechanical circulatory support devices.
- To discuss patient selection and the role of MCS as an alternative to heart transplantation.
Main Methods:
- Review of existing literature on heart failure therapies and mechanical circulatory support devices.
- Categorization of MCS devices based on flow, location, power, and support duration.
- Discussion of clinical indications and patient selection criteria for MCS.
Main Results:
- Mechanical circulatory support devices are a viable option for end-stage heart failure.
- Short-term devices are for anticipated myocardial recovery, while long-term devices support chronic failure or bridge to transplant.
- Long-term MCS can serve as a definitive alternative for select patients ineligible for transplantation.
Conclusions:
- Mechanical circulatory support devices are essential for managing refractory heart failure.
- Timely implantation of MCS is critical for optimal patient outcomes.
- Advancements in MCS, such as axial pumps, promise future improvements in device therapy.
Abstract:
Currently available approaches for patients with refractory heart failure include intravenous inotropic therapy, partial left ventriculectomy, dynamic cardiomyoplasty, mechanical circulatory support, and heart transplantation. Heart transplantation is limited by the availability of donor organs, which is never expected to meet the increasing demand. Numerous devices have been developed for circulatory support. Currently available devices differ in configuration, anatomic location, flow characteristics, and durability. Many devices are currently available for mechanical support, and they can generally be categorized as follows: 1) pulsatile or continuous blood flow; 2) internal (implantable) or external (extracorporeal); 3) pneumatically or electrically powered; and 4) for short-term or long-term support. Proper selection of patients for a given therapy has a major impact on clinical outcome. Early implantation of implantable devices, before the onset of multiple or irreversible end-organ failure, is essential. Short-term devices are indicated if myocardial recovery is anticipated, as in cases of postcardiotomy shock and acute myocarditis. Long-term devices are indicated for transitioning patients with end-stage myocardial failure to heart transplantation. Long-term assist devices may, in some selected cases, serve as an alternative to heart transplantation. This alternative will benefit both patients in chronic heart failure competing for a limited donor supply and patients with contraindications to transplantation, such as advanced age, previous malignancies, and renal dysfunction. The next generation of blood pumps to be applied clinically is likely to be axial pumps, which are valveless, miniaturized, intraventricular left ventricular assist devices.