Mechanical circulatory support and heart transplantation





Mechanical circulatory support


Despite recent progress in medical therapy, children with end-stage heart failure have limited treatment options. Mechanical circulatory support is used as a bridge to heart transplantation or recovery, in those patients who are refractory to maximal medical therapy. ECMO (Extra Corporeal Membrane Oxygenation) is the most common type of support in the pediatric population, allowing immediate biventricular and respiratory assistance. Use is typically limited to less than 2–3 weeks.


Lack of organ donors and the long waiting times have stimulated the development of long-term ventricular assist devices, such as Berlin Heart™ or Heart Ware™. Their use can exceed 1 year. Berlin Heart™ is an air-driven pulsatile flow device with an external pump. It can either support solely the left ventricle or provide biventricular support. Heart Ware™ is an internal pump located in the pericardial space. Unlike Berlin Heart™, it is a continuous-flow device .




Figure 1


Subcostal short-axis view in a patient with veno-arterial (VA) ECMO. Deoxygenated blood is sucked into the ECMO circuit from a venous cannula, the tip of which is typically located in the right atrium. After oxygenation, blood is returned to the body via an arterial cannula (not shown), usually inserted into the right common carotid artery. Ao , aorta; PA , pulmonary artery; RA , right atrium; RV , right ventricle.



Figure 2


(A) Patient with dilated cardiomyopathy. Apical four-chamber view demonstrating a Heart Ware™ device inflow cannula ( hollow arrow ) inserted into the apex of the left ventricle. The cannula is connected to a pump, which then returns the blood back to the aorta via an outflow cannula (not shown). (B) Heart Ware™ device inflow cannula ( hollow arrow ) seen from the parasternal short-axis view. LA , left atrium; LV , left ventricle; RA , right atrium; RV , right ventricle.



Figure 3


In children with restrictive cardiomyopathy, the ventricles are usually too small to accommodate a large cannula. However, severe atrial dilatation, typically present in this condition, provides enough space for atrial cannulation. (A) Patient with restrictive cardiomyopathy and biventricular support by two Berlin Heart™ pumps. Apical four-chamber view illustrating left atrial ( white arrow ) and right atrial ( hollow arrow ) inflow cannulae. (B) Color flow mapping demonstrating flow across the cannulae. LA , left atrium; LV , left ventricle; RA , right atrium; RV , right ventricle.



Figure 4


Suprasternal notch view in a child with a Berlin Heart™. (A) The dotted lines indicate the outline of the aortic arch. Note the presence of an aortic outflow cannula ( hollow arrow ). (B) Color flow mapping showing blood flow through the cannula to the aorta (Ao).

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Feb 2, 2021 | Posted by in CARDIOLOGY | Comments Off on Mechanical circulatory support and heart transplantation

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