**5. ECMO as a bridge to transplantation**

Cardiac transplant still remains the gold standard in treatment of end-stage heart failure. The scarcity of donors has led to the generation of a whole field of mechanical circulatory support devices which has brought in a new era in the treatment of advanced heart failure. The use of continuous flow LVADs as a bridge to transplantation (BTT) has become more popular and the mainstay of patients waiting on the transplant list [32]. More recently, VA-ECMO is being increasingly used as a rescue therapy [33, 34] However, this trend has now led to the use of ECMO as a direct bridge to transplantation in adults. This seems to be an attractive pathway for critically ill advanced heart failure patients waiting on the transplant wait list to get a heart very quickly it raises many questions about the feasibility of such an approach in the population. Though there is a very small portion of the

**149**

mortality [46].

**6. Conclusions**

*Extracorporeal Membrane Oxygenation as a Bridge to Cardiac Transplantation*

patients on the wait list who would be bridged directly on VA-ECMO to cardiac transplant, the lack of extensive literature and evidence for posttransplant survival of patients supported on ECMO makes this proposition questionable. Due to the large number of candidates waiting on the transplant list and too many high priority status 1A candidates in the wait list, the most recent organ allocation system has placed VA-ECMO bridge as the highest priority for cardiac transplant on the wait list [35]. This has a major disadvantage because of poor early and midterm posttransplant survival as compared to patients supported on CF-VADs [36]. It is therefore probably too early to use VA-ECMO as the highest priority for transplant

BTT in the adult population has remained controversial despite small studies reporting varied survival rates posttransplantation in this population. The decision to use CF-LVADS as a BTT was based on various studies which showed improvements in functional status and quality of life in this population [37]. Such data is

Therefore, the new system of allocation may reduce the transplant wait list mortality but may on the other hand increase the posttransplant mortality leading to a waste of organs in the setting of donor organ shortage. The most recent large retrospective analysis of the UNOS database showed a deceased survival in the early/mid posttransplant period [36]. Other studies from different countries have a

The literature on use of VA-ECMO as a direct bridge to heart transplantation in adults is scanty. The use of VA-ECMO in posttransplant primary graft failure showed poor outcomes [38–40]. Since patients supported on ECMO are critically ill and the time to finding an organ is short, the extensive social and psychological evaluation required for transplant evaluation is not possible which could lead to

Studies from France reported varying survival rates ranging from 51 to 70.4% at 1-year posttransplant in patients bridged on VA-ECMO [38, 41, 42]. Some of the caveats of these reports are the wait list mortality was not reported in the study by Jasseron et al. [38], while the duration of pretransplant ECMO support was not reported in the study by Rousse et al. [41] In the study Barth et al. [42], the survival was 100% at 1-year posttransplant though there were several adverse events and the study had a n = 8 with a mean age of 41 years. In a case series reported from Taiwan, 73% survived to hospital discharge in a cohort of 15 patients [43]. Mishra et al. [44] have reported a 1-year survival of 70%. A small study from Spain on posttransplant outcomes of patients bridged on ECMO showed no increase in mortality [45]. In France the special urgency wait list did improve the wait list mortality but also showed a significant increase in the posttransplant

The use of VA-ECMO as a technique for rescuing patients from cardiogenic shock is very attractive. However, considering the extensive set of complications and the mortality it brings with it makes it a less attractive option as a direct bridge to cardiac transplant. The literature currently on this subject is very scanty and limited to a few studies of small numbers of patients. The existing literature from France suggests a higher rate of posttransplant deaths even though the wait list mortality was reduced which does not seem to be an optimal way for organ allocation. In the light of present findings, further definitive research is needed for a

consensus on the role of VA-ECMO as a bridge to cardiac transplant.

*DOI: http://dx.doi.org/10.5772/intechopen.84935*

organ availability/allocation.

lacking in adults supported on VA-ECMO as BTT.

wide variety of data which are limited.

suboptimal candidate selection.

#### *Extracorporeal Membrane Oxygenation as a Bridge to Cardiac Transplantation DOI: http://dx.doi.org/10.5772/intechopen.84935*

patients on the wait list who would be bridged directly on VA-ECMO to cardiac transplant, the lack of extensive literature and evidence for posttransplant survival of patients supported on ECMO makes this proposition questionable. Due to the large number of candidates waiting on the transplant list and too many high priority status 1A candidates in the wait list, the most recent organ allocation system has placed VA-ECMO bridge as the highest priority for cardiac transplant on the wait list [35]. This has a major disadvantage because of poor early and midterm posttransplant survival as compared to patients supported on CF-VADs [36]. It is therefore probably too early to use VA-ECMO as the highest priority for transplant organ availability/allocation.

BTT in the adult population has remained controversial despite small studies reporting varied survival rates posttransplantation in this population. The decision to use CF-LVADS as a BTT was based on various studies which showed improvements in functional status and quality of life in this population [37]. Such data is lacking in adults supported on VA-ECMO as BTT.

Therefore, the new system of allocation may reduce the transplant wait list mortality but may on the other hand increase the posttransplant mortality leading to a waste of organs in the setting of donor organ shortage. The most recent large retrospective analysis of the UNOS database showed a deceased survival in the early/mid posttransplant period [36]. Other studies from different countries have a wide variety of data which are limited.

The literature on use of VA-ECMO as a direct bridge to heart transplantation in adults is scanty. The use of VA-ECMO in posttransplant primary graft failure showed poor outcomes [38–40]. Since patients supported on ECMO are critically ill and the time to finding an organ is short, the extensive social and psychological evaluation required for transplant evaluation is not possible which could lead to suboptimal candidate selection.

Studies from France reported varying survival rates ranging from 51 to 70.4% at 1-year posttransplant in patients bridged on VA-ECMO [38, 41, 42]. Some of the caveats of these reports are the wait list mortality was not reported in the study by Jasseron et al. [38], while the duration of pretransplant ECMO support was not reported in the study by Rousse et al. [41] In the study Barth et al. [42], the survival was 100% at 1-year posttransplant though there were several adverse events and the study had a n = 8 with a mean age of 41 years. In a case series reported from Taiwan, 73% survived to hospital discharge in a cohort of 15 patients [43]. Mishra et al. [44] have reported a 1-year survival of 70%. A small study from Spain on posttransplant outcomes of patients bridged on ECMO showed no increase in mortality [45]. In France the special urgency wait list did improve the wait list mortality but also showed a significant increase in the posttransplant mortality [46].
