The Impact of Pretransplantation Urgency Status and the Presence of a Ventricular Assist Device on Outcome After Heart Transplantation

Heart transplant outcomes in patients with mechanical circulatory support: cold storage versus normothermic perfusion organ preservation

OBJECTIVES

Patients with mechanical circulatory support bridged to a heart transplant (HTx) are at higher risk of postoperative graft dysfunction. In this subset, a mode of graft preservation that shortens graft ischaemia should be beneficial.

METHODS

The outcomes of 38 patients on mechanical circulatory support (extracorporeal life support, left ventricular assist device and biventricular assist device) who received a HTx between 2015 and 2020 were analysed according to the method of graft preservation: cold storage (CS) group, 24 (63%) or ex vivo perfusion (EVP) group, 14 (37%).

RESULTS

The median age was 57 (range 30-73) vs 64 (35-75) years (P = 0.10); 88% were men (P = 0.28); extracorporeal life support was more frequent in the CS group (54% vs 36%; P = 0.27) versus left ventricular and biventricular assist devices in the EVP group (46% vs 64%; P = 0.27). Clamping time was shorter in the EVP group (P < 0.001) and ischaemic time >4 h was higher in the CS group (P = 0.01). Thirty-day mortality was 13% (0-27%) in the CS group and 0% (P = 0.28) in the EVP group. A significantly lower primary graft failure [7% (0-23%) vs 42% (20-63%); P = 0.03] was observed in the EVP group. Survival at 1 year was 79 ± 8% (63-95%) in the CS group and 84 ± 10% (64-104%) in the EVP group (P = 0.95).

CONCLUSIONS

Our results support the use of ex vivo graft perfusion in patients on mechanical circulatory support as a bridge to a HTx. This technique, by shortening graft ischaemic time, seems to improve post-HTx outcomes.

Bridge to heart transplantation in patients with cardiogenic shock: a 20-year experience with two different surgical strategies

AIMS

We aimed to describe how treatment of patients in cardiogenic shock bridged to heart transplantation with mechanical circulatory support, using either biventricular assist devices (BVADs) or extracorporeal life support (ECLS), has evolved in the last 20 years in our centre.

METHODS

Since 1998, 72 patients with refractory heart failure and indication for heart transplantation have received mechanical circulatory support: 40 had an ECLS system and 32 a BVAD.

RESULTS

Early mortality was similar (17.5 vs. 9.4%, P = 0.25) regardless of the type of support. After a median support time of 8 (1-27) vs. 34 (0-385) days (P < 0.01), 70 vs. 65.6% (P = 0.69) of patients underwent transplantation in the two groups. Prior to transplantation, BVAD patients were more stable with lower need for mechanical ventilation (9 vs. 57%, P < 0.01) and dialysis (0 vs. 38%, P < 0.01). Thirty-day mortality after transplantation was similar (18 vs. 14%, P = 0.53). Patients with extracorporeal support had higher rates of renal (P = 0.02) and respiratory failure (P = 0.03), infections (P = 0.02), atrial fibrillation (P = 0.03) and longer ICU stay (P = 0.01). Late survival was similar, while 5-year freedom from coronary vasculopathy was higher in those with BVAD (P = 0.03).

CONCLUSION

Although ECLS provides faster and simpler assistance compared with BVADs, no differences in early and medium-term outcomes in the last 20 years were observed in patients with cardiogenic shock. However, BVADs provided longer duration of support, better multiorgan recovery allowing more adequate graft selection, resulting in a lower rate of posttransplant complications.

Short-term mechanical circulatory support as bridge to heart transplantation: paracorporeal ventricular assist device as alternative to extracorporeal life support

Extracorporeal life support (ECLS) is generally considered to be the treatment of choice for bridging to heart transplantation (HTx) patients with cardiogenic shock; however, alternative mechanical circulatory support (MCS) devices have been proposed with satisfactory results and, among those, paracorporeal systems have demonstrated to be safe and effective. This technology has been used for decades as bridge to transplant, especially in patients with advanced right ventricular dysfunction or evidence of multiorgan failure (MOF), which could be difficult to manage with an isolated left ventricular support. Paracorporeal systems are defined by having the pump located outside of the body, with inflow and outflow cannulas that traverse the skin connecting the pump with the heart and great vessels. They can be utilised in a uni- or bi-ventricular configuration and can provide pulsatile or continuous flow, depending on the device technology (pneumatic vs. centrifugal). In particular, pneumatic devices allow for patient mobilization and hospital discharge, improving rehabilitation and organ recovery while bridging to transplant. In our institution at the University Hospital of Udine, 34 pneumatic paracorporeal ventricular assist devices (VADs) have been implanted since 1998: in most cases (32 pts), as biventricular support for patients in INTERMACS class I-II. After a median support time of 34 (range, 0-385) days, with 19 patients (56%) supported for more than 1 month, 23 patients (68%) underwent HTx and 3 (9%) were successfully weaned to hospital discharge, resulting in an overall combined 76% survival to HTx or weaning. After transplant, the survival rate was similar to the one of the patients not bridged with MCS. In conclusion, pneumatic VADs can effectively assist patients with severe biventricular failure, especially those with contraindications to ECLS or expected long waiting times for HTx. Moreover, they can potentially result in hospital discharge, optimal organ and patient recovery and donor-recipient matching, resulting in a satisfactory transplant outcome.

How to cope with a temporarily aborted transplant program: solutions for a prolonged waiting period

BACKGROUND

Due to budgetary restrictions our university heart transplant program came to a standstill to be gradually restarted early 2011. Consequently waiting-times for transplantation increased dramatically beyond the usual 10-15 months. We reviewed the clinical results of this peculiar transplant program over the past 4 years.

METHODS

Since March 2011 until February 2015, 65 patients (age 48±23 years) were listed for heart transplantation. Eight patients (11%) of whom three in high emergency were transplanted without any form of mechanical assistance. Fifty-one patients required a left ventricular assist device (LVAD) Heartware (Heartware Inc., Miami Lakes, FL, USA) as a bridge-to-transplant due to terminal heart failure. Merely 5 listed patients remain without assistance.

RESULTS

One patient without assistance and 11 LVAD patients (22%) died on the waiting-list. Meanwhile 10 LVAD patients were transplanted after a 2-year waiting time (770±717 days). Four transplanted patients died of early graft failure none after LVAD explantation. Survival at 1 and 3 years was respectively 78 (72%) and 83 (78%) for transplanted and assisted patients (log-rank P=0.056). Cox multivariable regression analysis identified crash-to-burn patients (P=0.002) and waiting-times over 2 years (P=0.044) as risk factors for early death, while age above 60 (P=0.008) and ischemic aetiology (P=0.029) and pulmonary hypertension (P=0.092) were risk factors for survival.

CONCLUSIONS

In times of donor shortage mechanical assistance proves very effective as bridge-to-transplant in patients for whom candidacy follows the standard inclusion procedures. In our settings, a steep increase in LVAD implantation served to salvage patients for whom transplantation became jeopardized due to an ever increasing waiting-time. Circulatory LVAD support could be considered as primary therapy in the future.