**4. TandemHeart**

**3. Impella**

70 Heart Transplantation

arrhythmias.

**Figure 2.** İmpella.

sary to allow heart recovery.

catheter ablation of hemodynamic condition [4].

Impella is a pump which pulls blood from the left ventricle and expels into the ascending aorta (**Figure 2**). The system has a continuous-flow microaxial pump located at the distal end of the catheter. The device can be inserted via a standard catheterization procedure through the femoral artery. It is inserted into the left ventricle via a femoral cut down or through the axillary artery, and goes through the ascending aorta, across the valve and into the left ventricle. This pump can produce a flow from 2.5 to 5.0 L/min. The principal feature mechanism of the device is to reduce the ventricular work, and to provide the circulatory support neces-

Unlike the IABP, the Impella device uses continuous axial flow and consequently does not require pressure timing or electrocardiographic timing, allowing for stable output despite

The device is mainly used during high-risk percutaneous coronary interventions (PCI) and in cardiogenic shock that is resistant to medical management. The device can also be used to hemodynamic support for the patient with severe left-ventricular dysfunction undergoing

In the setting of CS, two small trials have been performed with the Impella 2.5 pMCS, both using IABP therapy as the control therapy. The ISAR-SHOCK (efficacy study of LV assist device to treat patients with cardiogenic shock) trial randomized 26 patients between IABP and the Impella 2.5 in the setting of CS complicating AMI. The primary endpoint was the

> The TandemHeart is a continuous-flow centrifugal-assist device placed percutaneous way. Cannulas are inserted through the femoral vein and advanced across the intra-atrial septum into the left atrium (**Figure 3**). The pump withdraws oxygenated blood from the left atrium and returns to the femoral artery via arterial cannulas. The pump is capable of delivering blood flow up to 5.0 L/min.

> The TandemHeart is creating a left atrial-to-femoral artery bypass that provides hemodynamic support during mainly high-risk coronary interventions and cardiogenic shock after cardiac surgery.

> Among all other available percutaneous circulatory support options, only TandemHeart provides a steady supply of oxygenated blood to the body, while decompressing the left ventricle to reduce the work of the heart.

> The device provides active hemodynamic support in patients who have little residual ventricular function and also can remain implanted for up to 3 weeks. For these reasons, if patients in advanced heart failure is too sick for immediate LVAD placement or transplantation, the TandemHeart may serve as a bridge-to-recovery, LVAD placement (as a bridge-to-bridge), or even transplantation.

cardiac function and mainly uses in isolated severe respiratory failure. Veno-venous ECMO is reserved for patients in isolated respiratory failure with no significant cardiac dysfunction. Central ECMO can be applied after cardiac surgery if the heart cannot be weaned from the heart-lung machine due to post-cardiotomy syndrome. Cannulas, which are inserted for heart lung machine, can be connected to the ECMO circuit and the sternum leaves open and patient

Role of Short-Term Percutaneous Mechanical Circulatory Support Devices as Bridge-to-Heart…

http://dx.doi.org/10.5772/intechopen.75094

73

With cardiac failure, VA-ECMO is the preferred method because it provides urgent circulatory support with oxygenation in the event of sudden heart failure, thus preventing organ damage. For this reason, it may help to support a patient who is awaiting a heart transplant. Among other devices, one advantage of ECMO is providing hemofiltration and dialysis. The connectors have been incorporated between the oxygenator outlet and pump inlet so that a continuous renal replacement therapy (CRRT) device can be attached to the extracorporeal circuit. In a VA-ECMO setting, when the heart has recovered, but if the lungs are still poorly functioning, the native cardiac output bounces against the pumped blood, usually in the aortic arch region. Accordingly, the coronary arteries, and to a variable degree the supra-aortic vessel as well, are provided with hypoxic blood, heart, and brain are harmed. Upper extremity cyanosis has brought up the term "Harlequin syndrome." Therapeutic options consist of a relocation of the arterial cannula in to right subclavian artery or aorta, or in converting the system

The healthcare team looking after patients on short-term percutaneous MCS aim to avoid any complications that may occur from being on these devices. Some of the more serious problems that may occur in these patients include: (1) bleeding especially from

can transfer to the ICU with ECMO support for healing period.

into a VA-V-setting.

**Figure 4.** ECMO.

**Figure 3.** TandemHeart.
