**4. Conclusion(s)**

Full support is sufficient when hemodynamic variables and microperfusion are normalized— VA ECMO usually provides normal oxymetric parameters if the patient is well supported. MAP goal usually is around 70, CVP < 15, SVO2 > 60%, serum lactate <2.0 mmol/L, and O2 saturation > 95%. Since the pulmonary flow is shunted throw the ECLS system, pulmonary artery pressures are expected to be very low, and most of the times cardiac index cannot be measured. Pulsatile waveforms are almost invisible or show a very low pulse pressure gradi-

Usually, in the range of 3–7 days, it is possible to see some degree of heart recovery. Pulse pressure may rise above 20 mmHg, CI may be measurable through PAC, pulmonary pressures may rise, and the patient may be hemodynamically stable with a lower flow on ECLS system. At this point, the weaning protocol should require an echocardiographic evaluation to reassess biventricular function. In adults, patients showing aortic time-velocity integral (VTI) ≥10 cm, left ventricular ejection fraction (LVEF) >20–25%, and lateral mitral annulus peak systolic velocity (TDSa) ≥6 cm/s at minimal ECMO flow were all successfully weaned [68].

Although ECMO may provide adequate support, it has limitations such as insufficient LV unloading, limited time of support, and risks of thromboembolic and vascular complications. High pressures in left chambers may not be easily documented, and the patient may run with hemodynamic instability. Non-treatable low flow related to sequestration of stroke volume in the lungs, secondary of left chambers distention, and inability of the heart to decompress from ECMO post-load augmentation may be seen. A documented left-side heart high pressure requires an immediately strategy to unload left chambers and re-establish the desired flow. A drainage cannula in left atrium or ventricle that allows a fast connection on the ECMO circuit permits good drainage and is a feasible choice. It is important to note that, in this case,

In case of recovery of the left ventricle's ability to unload, the left cannula may be removed before starting the weaning protocol or just reducing the ECMO to allow filing up the ventricle and considering weaning. Intra-aortic balloon pump has been documented, but in a different scenario setting, as a way to reducing systemic vascular resistance, helping to prevent LV distention, during the VA ECMO run [69]. More recently, in the largest US-based retrospective study, the addition of Impella to VA-ECMO for patients with refractory cardiogenic shock was associated with lower all-cause 30-day mortality, lower inotrope use, and comparable safety profiles as compared with VA-ECMO alone. This study reinforces the importance of LV decompression as an important factor to improve outcomes during VA ECMO in severe ventricular dysfunction [70]. If recovery is not noted on PGD, other strategies should be considered and palliative care may be an option. Although we were able to prolong ECMO support in an infant up to 44 days until recovery, a biventricular support including a durable VAD or a total artificial heart may be an option in selected patients. Since there is lack of evidence to support use of those alternatives on PGD, the selection of a device should be made according to the patient's clinical

Between January 2007 and December 2013, a total of 71 heart transplantations were performed in patients with advanced heart failure and 11 (15.5%) of these patients presented PGD [71].

optimum flow will be achieved after a left-side drainage cannula insertion.

ent (less than 20 mm Hg).

98 Advances in Extra-corporeal Perfusion Therapies

condition and the center's experience.

**3.1. Personal experience**

The aim of circulatory assistance in PGD is always cardiac recovery. Thus, the characteristics of the ideal device must comply with the following requirements: ability to be quickly installed, allowing the rapid re-establishment of cardiac output in order to maintain adequate tissue perfusion and reverse multiorgan dysfunction, reducing ventricular filling pressures, promoting myocardial protection with increased coronary flow, and having a low complication rate.

Heart decompression is important for a successful recovery since intracavitary hypertension curtails subendocardial coronary perfusion, especially in those patients who had no electrical activity or lacked sufficient contractile activity for adequate LV decompression.

The Journal of Heart and Lung Transplantation. 2012;**31**(10):1052-1064. DOI: 10.1016/j.

Mechanical Circulatory Support (MCS) for Primary Graft Dysfunction (PGD)

http://dx.doi.org/10.5772/intechopen.76697

101

[3] Lund LH, Edwards LB, Kucheryavaya AY, et al. The registry of the International Society for Heart and Lung Transplantation: Thirtieth official adult heart transplant report–2013; focus theme: Age. The Journal of Heart and Lung Transplantation. 2013;**32**(10):951-964.

[4] Iyer A, Kumarasinghe G, Hicks M, et al. Primary graft failure after heart transplantation.

[5] Kobashigawa J, Zuckermann A, Macdonald P, et al. Report from a consensus conference on primary graft dysfunction after cardiac transplantation. The Journal of Heart and

[6] Blume ED, Rosenthal DN, Rossano JW, et al. Outcomes of children implanted with ventricular assist devices in the United States: First analysis of the pediatric interagency registry for mechanical circulatory support (PediMACS). The Journal of Heart and Lung

[7] Kirklin JK, Naftel DC, Pagani FD, et al. Seventh INTERMACS annual report: 15,000 patients and counting. The Journal of Heart and Lung Transplantation. 2015;**34**(12):1495-

[8] Cabrera AG, Sundareswaran KS, Samayoa AX, et al. Outcomes of pediatric patients supported by the HeartMate II left ventricular assist device in the United States. The Journal of Heart and Lung Transplantation. 2013;**32**(11):1107-1113. DOI: 10.1016/j.

[9] Burki S, Adachi I. Pediatric ventricular assist devices: Current challenges and future prospects. Vascular Health and Risk Management. 2017;**13**:177-185. DOI: 10.2147/

[10] Gregoric ID, Cohn WE, Frazier OH. Diaphragmatic implantation of the HeartWare ventricular assist device. The Journal of Heart and Lung Transplantation. 2011;**30**(04):467-

[11] Na SJ et al. Vasoactive inotropic score as a predictor of mortality in adult patients with cardiogenic shock: Medical therapy versus ECMO. Revista Española de Cardiología.

[12] Gaies MG, Jeffries HE, Niebler RA, Pasquali SK, Donohue JE, Yu S, et al. Vasoactiveinotropic score is associated with outcome after infant cardiac surgery: An analysis from the pediatric cardiac critical care consortium and virtual PICU system registries. Pediatric Critical Care Medicine. 2014 Jul;**15**(6):529-537. DOI: 10.1097/PCC.0000000000000153 [13] Cooper DK, Novitzky D, Wicomb WN. The pathophysiological effects of brain death on potential donor organs, with particular reference to the heart. Annals of the Royal

[14] Ryan JB, Hicks M, Cropper JR, et al. Functional evidence of reversible ischemic injury immediately after the sympathetic storm associated with experimental brain death.

470. DOI: 10.1016/j.healun.2010.11.014. [pub ahead of print]

College of Surgeons of England. 1989;**71**(4):261-266

Journal of Transplantion. 2011;**2011**:175768. DOI: 10.1155/2011/175768

Lung Transplantation. 2014;**33**(4):327-340. DOI: 10.1016/j.healun.2014.02.027

Transplantation. 2016;**35**(05):578-584. DOI: 10.1016/j.healun.2016.01.1227

healun.2012.08.002

DOI: 10.1016/j.healun.2013.08.006

1504. DOI: 10.1016/j.healun.2015.10.003

2018. DOI: 10.1016/j.rec.2018.01.003

healun.2013.07.012

VHRM.S82379

Regardless of showing complete recovery, patients with PGD have a higher mortality when multiple organs were involved. Hence, there is need for strengthened intensive care in this population, systematically focused on the management of organs and systems and on the prevention of sepsis.

The rapid hemodynamic deterioration due to PGD shows that the earlier the implantation (operation room), the best are the outcomes for weaning and survival. Patients in whom ECMO was initiated due to cardiac arrest had a poor outcome, and the appropriate timing was certainly neglected.
