What Is Heart Transplantation?
A heart transplant is a procedure that involves replacing the heart with one from an organ donor. This is only utilized when the person is too unwell to survive without a transplant and meets specific criteria. Heart transplants are highly successful due to medical advancements. People can live for years, even decades, after receiving a new heart. Patients with refractory, chronic, or acute heart failure may require a heart transplant.
The most usual approach is an orthotopic heart transplant, but heterotopic transplants have also been described and accomplished. Patients with debilitating symptoms despite adequate medical therapy or patients with refractory arrhythmias with medical and electrophysiological procedures are the primary criteria for transplant in chronic heart failure. A heart transplant is recommended for patients with acute heart failure who have not responded to inotropes or mechanical circulatory devices.
What Are Mechanical Circulatory Support Devices?
Mechanical circulatory support devices (MCSDs) replace part of the mechanical tasks of a failing heart, increasing cardiac output and organ perfusion. MCS yields major advances in longevity and quality of life for patients with severe heart failure. They have the potential to assist many patients with end-stage heart failure who are unable to be transplanted due to a dearth of suitable organs or economic barriers.
MCS devices are intended to offer hemodynamic support and assist patients in maintaining proper end-organ perfusion. Temporary MCS devices are designed to support a variety of causes, including cardiogenic shock resistant to pharmacological therapy, high-risk percutaneous coronary procedures, myocardial recovery, and as an alternative to definitive therapy (permanent MCS devices or heart transplantation).
What Are Temporary Mechanical Circulatory Support Devices?
The intra-aortic balloon pump (IABP), venoarterial extracorporeal membrane oxygenation (VA-ECMO), percutaneous ventricular assist devices (pVADs), and surgically implanted temporary ventricular assist devices (VADs) are among the current temporary MCS devices that are available.
-
IABP: IABP was the first temporary MCS invented and is still the most widely used today. Initially, IABPs were put in the proximal descending aorta using the femoral artery. Because it is inexpensive and simple to implant, the IABP is still the most commonly utilized MCS device.
-
ECMO: When used in the veno-arterial (VA) configuration, ECMO can offer hemodynamic support in addition to its veno-venous application for lung failure. Peripheral cannulation is used to start VA-ECMO. Oxygenated blood is reintroduced into the bloodstream via the femoral artery, while deoxygenated blood is extracted from the internal jugular vein.
-
Surgically-Implanted Temporary VADs: In addition to transcutaneous temporary MCS devices, some devices are surgically implanted through a median sternotomy. To give LV (left ventricle), RV (right ventricle), or biventricular support, the CentriMag, a magnetically levitated pump, is the most frequently surgically placed temporary device.
-
pVAD: Continuous flow pumps in pVADs, including the Impella and TandemHeart, provide circulatory support. These pumps can be inserted via a completely percutaneous technique, tiny incisions, and short grafts.
-
LVAD: The most popular type of durable MCS is LVADs (left ventricular assist devices). The original generation of LVADs were pulsatile devices that supported patients' hemodynamics but had drawbacks such as a large recipient body habitus, frequent device exchanges, and substantial surgical dissection.
What Are the Innovations in Heart Transplantation and Mechanical Circulatory Support Devices?
Innovation is the creation, adoption, or integration of a value-added novelty. Technological and surgical developments are inextricably linked, and some medical specializations, such as mechanical circulatory support systems, are particularly technologically driven. New implantation strategies are often established due to novel breakthroughs, such as device downsizing.
Engineers, on the other hand, are driven to adapt and reinvent technical equipment due to physicians' ongoing desire for answers to surgical or clinical issues and patient preferences. Tens of thousands of Americans alone suffer from advanced heart failure, which has a significant morbidity and death rate. The optimum course of treatment is cardiac transplantation, although historically, donor availability has limited this option. Significant progress has been made recently in organ allocation, organ preservation, donor-recipient matching, and donor pool extension. To reduce waiting mortality, the sickest patients are given priority under the present heart allocation method.
More accurate matching of donors and recipients is made possible by developments in donor organ selection, such as anticipated heart mass calculations and more advanced antibody detection techniques for patients sensitized to allergens. The future of heart failure surgery is LIS (less invasive surgery) techniques, which have advantageous adverse event profiles. Several novel surgical implantation techniques have been developed as a result of the shrinking of VADs, and these are particularly helpful in difficult circumstances. Implantation techniques will advance further due to significant innovations, including fully implantable devices, further miniaturization, unique technology, and new or enhanced surgical equipment.
Conclusion:
BTT (bridge to transplantation) therapy using MCS devices has developed quickly. Historically, the most widely utilized type of temporary MCS was the IABP. Nonetheless, the usage of IABPs has decreased due to the introduction of percutaneous VADs (ventricular assist devices) such as the Impella and the TandemHeart.
The creation of temporary MCS devices that can offer support in the event of RV heart failure and percutaneous VADs that can completely unload the LV are the results of recent (right ventricle) technological developments. Improvements in durable LVAD technology have improved BTT patients' long-term survival, both while wearing the device and following transplantation.
