Impact of Heart Transplantation on Survival in Patients on Venoarterial Extracorporeal Membrane Oxygenation at Listing in France

Intra-operative Risk Factors Affecting Mortality after Heart Transplantation: A Referral Center Experience in Iran

Background

Heart transplantation is the preferred treatment for end-stage heart failure. This study investigated the intra-operative risk factors affecting post-transplantation mortality.

Methods

This single-center retrospective cohort study examined 239 heart transplant patients over eight years, from 2011-2019, at the oldest dedicated cardiovascular center, Shahid Rajaee Hospital (Tehran, Iran). The primary evaluated clinical outcomes were rejection, readmission, and mortality one month and one year after transplantation. For data analysis, univariate logistic regression analyses were conducted.

Results

In this study, 107 patients (43.2%) were adults, and 132 patients (56.8%) were children. Notably, reoperation due to bleeding was a significant predictor of one-month mortality in both children (OR=7.47, P=0.006) and adults (OR=172.12, P<0.001). Moreover, the need for defibrillation significantly increased the risk of one-month mortality in both groups (children: OR=38.00, P<0.001; adults: OR=172.12, P<0.001). Interestingly, readmission had a protective effect against one-month mortality in both children (OR=0.02, P<0.001) and adults (OR=0.004, P<0.001). Regarding one-year mortality, the use of extracorporeal membrane oxygenation (ECMO) was associated with a higher risk in both children (OR=7.64, P=0.001) and adults (OR=12.10, P<0.001). For children, reoperation due to postoperative hemorrhage also increased the risk (OR=5.14, P=0.020), while defibrillation was a significant risk factor in both children and adults (children: OR=22.00, P<0.001; adults: OR=172.12, P<0.001). The median post-surgery survival was 22 months for children and 24 months for adults.

Conclusion

There was no correlation between sex and poorer outcomes. Mortality at one month and one year after transplantation was associated with the following risk factors: the use of ECMO, reoperation for bleeding, defibrillation following cross-clamp removal, and Intensive Care Unit (ICU) stay. Readmission, on the other hand, had a weak protective effect.

Prognostic Value of APACHE IV Score in Patients Bridged to Heart Transplantation on ECMO

BACKGROUND

Methods for risk stratification of candidates for heart transplantation (HTx) supported by extracorporeal membrane oxygenation (ECMO) are limited. We evaluated the reliability of the APACHE IV score to identify the risk of mortality in this patient subset in a multicenter study.

METHODS

Between January 2010 and December 2022, 167 consecutive ECMO patients were bridged to HTx; they were divided into two groups, according to a cutoff value of APACHE IV score, obtained by receiver operating characteristic curve analysis for 90-day mortality. Kaplan-Meier survival curves were plotted, and compared through the log-Rank test. Cox regression model was used to estimate which factors were associated with survival.

RESULTS

The 90-day mortality prediction of the APACHE IV score showed an area under the curve of 0.87 (95% CI: 0.80-0.94), with a cutoff value of 49 (specificity 91.7%-sensibility 69.6%). 125 patients (74.8%) showed an APACHE IV score value < 49 (Group A), and 42 (25.2%) ≥ 49 (Group B). 90-day mortality was 11.2% in Group A and 76.2% in Group B (p < 0.01). Survival at 1 and 5 years was 85.5%, 77% versus 23.4%, 23.4% (p < 0.01) in Groups A and B. Mortality correlated at univariable analysis with recipient age, body mass index, mechanical ventilation, APACHE IV score, and platelets number. At multivariable analysis only APACHE IV score (HR: 1.07 [1.05-1.09, 95% CI]) independently affected survival.

CONCLUSIONS

The APACHE IV score represents a powerful predictor of survival in patients bridged to HTx on ECMO support, and could guide candidacy of patients on ECMO.

Veno-arterial ECMO ventricular assistance as a direct bridge to heart transplant: A single center experience in a low-middle income country

INTRODUCTION

The use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) as a direct bridge to heart transplantation (BTT) is not common in adults worldwide. BTT with ECMO is associated with increased early/mid-term mortality compared with other interventions. In low- and middle-income countries (LMIC), where no other type of short-term mechanical circulatory support is available, its use is widespread and increasingly used as rescue therapy in patients with cardiogenic shock (CS) as a direct bridge to heart transplantation (HT).

OBJECTIVE

To assess the outcomes of adult patients using VA-ECMO as a direct BTT in an LMIC and compare them with international registries.

METHODS

We conducted a single-center study analyzing consecutive adult patients requiring VA-ECMO as BTT due to refractory CS or cardiac arrest (CA) in a cardiovascular center in Argentina between January 2014 and December 2022. Survival and adverse clinical events after VA-ECMO implantation were evaluated.

RESULTS

Of 86 VA-ECMO, 22 (25.5%) were implanted as initial BTT strategy, and 52.1% of them underwent HT. Mean age was 46 years (SD 12); 59% were male. ECMO was indicated in 81% for CS, and the most common underlying condition was coronary artery disease (31.8%). Overall, in-hospital mortality for VA-ECMO as BTT was 50%. Survival to discharge was 83% in those who underwent HT and 10% in those who did not, p < .001. In those who did not undergo HT, the main cause of death was hemorrhagic complications (44%), followed by thrombotic complications (33%). The median duration of VA-ECMO was 6 days (IQR 3-16). There were no differences in the number of days on ECMO between those who received a transplant and those who did not. In the Spanish registry, in-hospital survival after HT was 66.7%; the United Network of Organ Sharing registry estimated post-transplant survival at 73.1% ± 4.4%, and in the French national registry 1-year posttransplant survival was 70% in the VA-ECMO group.

CONCLUSIONS

In adult patients with cardiogenic shock, VA-ECMO as a direct BTT allowed successful HT in half of the patients. HT provided a survival benefit in listed patients on VA-ECMO. We present a single center experience with results comparable to those of international registries.

Outcomes in Heart Transplant Recipients by Bridge to Transplant Strategy When Using the SherpaPak Cardiac Transport System

The last several years have seen a rise in use of mechanical circulatory support (MCS) to bridge heart transplant recipients. A controlled hypothermic organ preservation system, the SherpaPak Cardiac Transport System (SCTS), was introduced in 2018 and has grown in utilization with reports of improved posttransplant outcomes. The Global Utilization And Registry Database for Improved heArt preservatioN (GUARDIAN)-Heart registry is an international, multicenter registry assessing outcomes after transplant using the SCTS. This analysis examines outcomes in recipients bridged with various MCS devices in the GUARDIAN-Heart Registry. A total of 422 recipients with donor hearts transported using SCTS were included and identified. Durable ventricular assist devices (VADs) were used exclusively in 179 recipients, temporary VADs or intra-aortic balloon pump (IABP) in 197, and extracorporeal membrane oxygenation (ECMO) in 14 recipients. Average ischemic times were over 3.5 hours in all cohorts. Severe primary graft dysfunction (PGD) posttransplant increased across groups (4.5% VAD, 5.1% temporary support, 21.4% ECMO), whereas intensive care unit (ICU) length of stay (18.2 days) and total hospital stay (39.4 days) was longer in the ECMO cohort than the VAD and IABP groups. A comparison of outcomes of MCS bridging in SCTS versus traditional ice revealed significantly lower rates of both moderate/severe right ventricular (RV) dysfunction and severe PGD in the SCTS cohort; however, upon propensity matching only the reductions in moderate/severe RV dysfunction were statistically significant. Use of SCTS in transplant recipients with various bridging strategies results in excellent outcomes.

Comparison of Veno-arterial Extracorporeal Membrane Oxygenation Configurations for Patients Listed for Heart Transplantation

BACKGROUND AND OBJECTIVES

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) as a bridge to eventual heart transplantation (HT) is increasingly used worldwide. However, the effect of different VA-ECMO types on HT outcomes remains unclear.

METHODS

This was a retrospective observational study of 111 patients receiving VA-ECMO and awaiting HT. We assessed 3 ECMO configuration groups: peripheral (n=76), central (n=12), and peripheral to central ECMO conversion (n=23). Cox proportional hazards regression and landmark analysis were conducted to analyze the effect of the ECMO configuration on HT and in-hospital mortality rates. We also evaluated adverse events during ECMO support.

RESULTS

HT was performed in the peripheral (n=48, 63.2%), central (n=10, 83.3%), and conversion (n=11, 47.8%) ECMO groups (p=0.133) with a median interval of 10.5, 16, and 30 days, respectively (p<0.001). The cumulative incidence of HT was significantly lower in the conversion group (hazard ratio, 0.292, 95% confidence interval, 0.145-0.586, p=0.001). However, there was no difference in in-hospital mortality (log-rank p=0.433). In the landmark analysis, in-hospital mortality did not differ significantly among the 3 groups. Although we did note a trend toward lower HT in the conversion group, the difference was not statistically significant. Surgical site bleeding occurred mainly in the central, while limb ischemia occurred mainly in the peripheral groups.

CONCLUSIONS

We suggest that if patients are being stably supported with their initial ECMO configuration, whether it is central or peripheral, it should be maintained, and ECMO conversion should only be cautiously performed when necessary.

Extended Support With the Impella 5.5: Transplant, ECMO, and Complications

We report midterm results of Impella 5.5 use with focus placed on bridge-outcomes, venoarterial extracorporeal membrane oxygenation (VA-ECMO) transition, complications, and risk factors for mortality. A retrospective review of patients implanted with the Impella 5.5 at our medical center was conducted. Forty patients were included with varying bridge strategies. Sixteen (40%) patients were supported for <14 days, 13 (32.5%) for 14-30 days, and 11 (27.5%) for >30 days. Thirty day mortality was 22.5% (9/40). Twenty-five (62.5%) were successfully bridged to transplant or durable left ventricular assist device (LVAD), while four (10.0%) recovered without the need for any further cardiac support. Five of 11 (60%) patients initially supported with VA-ECMO were either transitioned to durable left ventricular assist device (dLVAD; n = 3, 27.3%), transplanted (n = 1, 9.1%), or recovered (n = 1, 9.1%). Of nine patients with >moderate right ventricle (RV) dysfunction, five (55.6%) were successfully bridged to transplant or LVAD. Five (12.5%) patients required interval cannulation to VA-ECMO, often in the setting of RV dysfunction, and all (100%) were successfully transplanted. Lower pulmonary artery (PA) systolic pressure ( P = 0.029), among other factors, was associated with mortality. In summary, the Impella 5.5 may be able to effectively stabilize patients in refractory left ventricular predominant cardiogenic shock for extended durations, allowing time for mechanical circulatory support (MCS) and transplant evaluations.

Association Between Shock Etiology and 5-Year Outcomes After Venoarterial Extracorporeal Membrane Oxygenation

BACKGROUND

Outcomes of patients requiring venoarterial extracorporeal membrane oxygenation (VA-ECMO) vary greatly by etiology, but large studies that incorporate the spectrum of shock supported with ECMO are rare.

OBJECTIVES

The purpose of this study was to describe the etiology-related outcome of patients with shock supported with peripheral VA-ECMO.

METHODS

All consecutive adults with peripheral VA-ECMO between January 2015 and August 2018 at Pitié-Salpêtrière Hospital (Paris, France) were included in this retrospective observational study. The indication for VA-ECMO was cardiogenic shock. Rates of hospital death and neurological, renal, and pulmonary complications were evaluated according to etiology.

RESULTS

Among 1,253 patients, hospital and 5-year survival rates were, respectively, 73.3% and 57.3% for primary graft failure, 58.6% and 54.0% for drug overdose, 53.2% and 45.3% for dilated cardiomyopathy, 51.6% and 50.0% for arrhythmic storm, 46.8% and 38.3% for massive pulmonary embolism, 44.4% and 42.4% for sepsis-induced cardiogenic shock, 37.9% and 32.9% for fulminant myocarditis, 37.3% and 31.5% for acute myocardial infarction, 34.6% and 33.3% for postcardiotomy excluding primary graft failure, 25.7% and 22.8% for other/unknown etiology, and 11.1% and 0.0% for refractory vasoplegia shock. Renal failure requiring hemodialysis developed in 50.0%, neurological complications in 16.0%, and hydrostatic pulmonary edema in 9.0%.

CONCLUSIONS

Although the outcome differs depending on etiology, this difference is related more to the severity of the situation associated with the cause rather than the cause of the shock per se. Survival to 5 years varied by cause, which may reflect the natural course of the chronic disease and illustrates the need for long-term follow-up.

A bridge-to-bridge approach to heart transplantation using extracorporeal membrane oxygenation and total artificial heart

BACKGROUND

This study aims to describe the outcomes after heart transplantation using a bridge-to-bridge strategy with a sequence of extracorporeal membrane oxygenation (ECMO) support followed by temporary total artificial heart implantation (TAH-t).

METHODS

A retrospective, multicenter analysis of 54 patients who underwent TAH-t implantation following an ECMO for cardiogenic shock was performed (ECMO-TAH-t group). A control group of 163 patients who underwent TAH-t implantation as a direct bridge to transplantation (TAH-t group) was used to assess this strategy's impact on outcomes.

RESULTS

Fifty-four patients, averaging 47 ± 13 year old, underwent implantation of a TAH-t after 5.3 ± 3.4 days of ECMO perfusion for cardiogenic shock. In the ECMO-TAH-t group, 20 patients (20/54%; 37%) died after TAH-t implantation and 57 patients (57/163%; 35%) died in the TAH-t group (Gray test; P = .49). The top 3 causes of death of patients on TAH-t support were multisystem organ failure (40%), sepsis (20%), and neurologic events (20%). Overall, 32 patients (32/54%; 59%) underwent heart transplantation in the ECMO-TAH-t group compared with 106 patients (106/163%, 65%) in the TAH-t group (P = .44). No significant difference in survival was observed at 6 months, 1 year, and 3 years after heart transplant (ECMO-TAH-t group: 94%, 87%, and 80% vs 87%, 83%, and 76% in the TAH-t group, respectively). Deterioration of liver function (bilirubin, aspartate transaminase, and alanine aminotransferase levels on TAH-t) was associated with increased mortality before heart transplant in both groups.

CONCLUSIONS

Sequential bridging from ECMO to TAH-t followed by heart transplantation is a viable option for a group of highly selected patients.

Impact of the 2018 French two-score allocation scheme on the profile of heart transplantation candidates and recipients: Insights from a high-volume centre

BACKGROUND

In 2018, a new cardiac allograft allocation scheme, based on an individual scoring system, considering the risk of death both on the waiting list and after heart transplantation, was implemented in France.

AIM

To assess the impact of this new scheme on the profile of transplantation candidates and recipients.

METHODS

In this single-centre retrospective study, we included consecutive patients listed and/or transplanted between 01 January 2012 and 30 September 2021 at La Pitié-Salpêtrière Hospital. Baseline characteristics of patients were retrieved from the national CRISTAL registry and were compared according to the type of allocation scheme (before or after 2018).

RESULTS

A total of 1098 newly listed transplantation candidates and 855 transplant recipients were included. One-year mortality rates after listing and after transplantation were 12.4% and 20%, respectively. At listing, the proportion of candidates on inotropes significantly declined following the scheme update (26.3 versus 20.9%; P=0.038), reflecting a change in medical practice. At transplantation, recipients had worse kidney function (estimated glomerular filtration rate<60mL/min/1.73 m²: old scheme, 29.7%; new scheme, 46.4%; P<0.001) and were more likely to be on extracorporeal membrane oxygenation support (33.5% versus 28.1%; P=0.080) under the new scheme, reflecting the prioritization of more severe patients. Outcomes after transplantation were not significantly influenced by the allocation system.

CONCLUSIONS

The implementation of the 2018 French allocation scheme had a limited impact on the profile of transplantation candidates, but selected more severe patients for transplantation without significant impact on outcomes after transplantation.

Risk stratification of patients listed for heart transplantation while supported with extracorporeal membrane oxygenation

OBJECTIVES

Extracorporeal membrane oxygenation (ECMO) is used to support patients in severe cardiogenic shock. In the absence of recovery, these patients may need to be listed for heart transplant (HT), which offers the best long-term prognosis. However, posttransplantation mortality is significantly elevated in patients who receive ECMO. The objective of the present study was to describe and risk-stratify different profiles of patients listed for HT supported by ECMO.

METHODS

Patients listed for HT in the United Network for Organ Sharing database were analyzed. The primary outcome was 1-year survival and was assessed in patients bridged to transplant with ECMO (ECMO_BTT) and patients who were previously supported on ECMO but had it removed before HT (ECMO_REMOVED).

RESULTS

Among 65,636 adult candidates listed for HT (between 2001 and 2017), 712 were supported on ECMO, 292 of whom (41%) underwent HT (ECMO_BTT, n = 202; ECMO_REMOVED, n = 90). Most of the patients with ECMO_REMOVED were transplanted with a ventricular assist device. In ECMO_BTT, recipient age (each 10-year increase), time on the waitlist (both defined as minor risk factors), need for dialysis, and need for mechanical ventilation (both defined as major risk factors) were independent predictors of mortality. ECMO_REMOVED and ECMO_BTT with no risk factors showed 1-year survival comparable to that in patients who were never supported on ECMO. Compared with patients who were never on ECMO, patients in ECMO_BTT group with minor risk factors, 1 major risk factor, and 2 major risk factors had ~2-, ~5-, and >10-fold greater 1-year mortality, respectively (P < .05).

CONCLUSIONS

The HT recipients in the ECMO_REMOVED and ECMO_BTT groups with no risk factors showed similar survival as the HT recipients who were never supported on ECMO. In the ECMO_BTT group, posttransplantation mortality increased significantly with increasing risk factors.

State of the art - Extracorporeal membrane oxygenation as a bridge to thoracic transplantation

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has revolutionized the treatment of refractory cardiac and respiratory failure, and its use continues to increase, particularly in adults. However, ECMO-related morbidity and mortality remain high.

MAIN TEXT

In this review, we investigate and expand upon the current state of the art in thoracic transplant and extracorporeal life support (ELS). In particular, we examine recent increase in incidence of heart transplant in patients supported by ECMO; the potential changes in patient care and selection for transplant in the years prior to updated United Network for Organ Sharing (UNOS) organ allocation guidelines versus those in the years following, particularly where these guidelines pertain to ECMO; and the newly revived practice of heart-lung block transplants (HLT) and the prevalence and utility of ECMO support in patients listed for HLT.

CONCLUSIONS

Our findings highlight encouraging outcomes in patients bridged to transplant with ECMO, considerable changes in treatment surrounding the updated UNOS guidelines, and complex, diverse outcomes among different centers in their care for increasingly ill patients listed for thoracic transplant.

Lack of volume-outcome association in ECMO bridge to heart transplantation

BACKGROUND

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used as a bridge to cardiac transplantation. As the 2018 United Network for Organ Sharing (UNOS) heart allocation policy change elevated waitlist status for patients receiving mechanical circulatory support (MCS), we aimed to determine if a center's annual heart transplant volume was associated with ECMO-support duration and posttransplant outcomes.

METHODS

Adults heart transplant candidates between January 1, 2011, and December 31, 2021, were isolated in the UNOS database. VA-ECMO use was identified at the time of listing for transplant. Average annual transplant volume was calculated by the center, with stratification as high (≥20 cardiac transplants, high volume center [HVC]) or low (<20 cardiac transplants, low volume center [LVC]) volume centers. Results are reported as mean (interquartile range) or n (%).

RESULTS

In total, 543 patients at HVCs and 275 at LVCs were listed for transplant supported with VA-ECMO. Those listed at HVCs were more likely to be supported by intra-aortic balloon pump (103 [19%] vs. 32 [11.6%], p = .008) and inotropes (267 [49.2%] vs. 106 [38.5%], p = .004) at time of listing. Patients at HVCs received ECMO support for 6 [4-9] days, compared to 8 [4-15] days at low-volume centers (p = .030), and but were cannulated a similar time before listing (2 [1-5] vs. 3 [1-7] days, p = .517). There were no differences in rates of transplant (p = .2126), waitlist mortality (p = .8645), delisting due to clinical deterioration (p = .8419), or recovery (p = .1773) between groups. Among transplanted patients, there were no differences in support duration (6 [4-8] vs. 6 [4-10], p = .187), or time from registration to transplant (5 [2-20] vs. 7 [3-22] days, p = .560). Posttransplant survival did not vary (p = .293).

CONCLUSIONS

LVCs can successfully bridge patients to transplant with VA-ECMO and achieve comparable outcomes to HVCs.

Veno-Arterial Extracorporeal Membrane Oxygenation as a Bridge to Heart Transplant-Change of Paradigm

Despite advances in medical therapy and mechanical circulatory support (MCS), heart transplant (HT) remains the gold standard therapy for end-stage heart failure. Patients in cardiogenic shock require prompt intervention to reverse hypoperfusion and end-organ damage. When medical therapy becomes insufficient, MCS should be considered. Historically, it has been reported that critically ill patients bridged with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) directly to HT have worse outcomes. However, when the heart allocation system gives the highest priority to patients on VA-ECMO support, those patients have a higher incidence of HT and a lower incidence of death or removal from the transplant list. Moreover, patients with a short waiting time on VA-ECMO have a similar hazard of mortality to non-ECMO patients. According to the reported data, bridging with VA-ECMO directly to HT may be a solution in the selection of critically ill patients when the anticipated waiting list time is short. However, when a prolonged waiting time is expected, more durable MCS should be considered. Regardless of the favorable results of the direct bridging to HT with ECMO in selected patients, the superiority of this strategy compared to the bridge-to-bridge strategy (ECMO to durable MCS) has not been established and further studies are mandatory in order to clarify this issue.

TEMPORAL TRENDS IN THE USE AND OUTCOMES OF TEMPORARY MECHANICAL CIRCULATORY SUPPORT AS A BRIDGE TO CARDIAC TRANSPLANTATION IN SPAIN. FINAL REPORT OF THE ASIS-TC STUDY

BACKGROUND

We aimed to describe recent trends in the use and outcomes of temporary mechanical circulatory support (MCS) as a bridge to heart transplantation (HTx) in Spain.

METHODS

Retrospective case-by-case analysis of 1,036 patients listed for emergency HTx while on temporary MCS in 16 Spanish institutions from January 1st, 2010 to December 31st, 2020. Patients were classified in 3 eras according to changes in donor allocation criteria (Era 1: January 2010/May 2014; Era 2: June 2014/May 2017; Era 3: June 2017/December 2020).

RESULTS

Over time, the proportion of candidates listed with intra-aortic balloon pumps decreased (Era 1 = 55.9%, Era 2 = 32%, Era 3 = 0.9%; p < 0.001), while the proportion of candidates listed with surgical continuous-flow temporary VADs (Era 1 = 10.6%, Era 2 = 32%, Era 3 = 49.1%; p < 0.001) and percutaneous VADs (Era 1 = 0.3%, Era 2 = 6.3%; Era 3 = 17.2%; p < 0.001) increased. Rates of HTx increased from Era 1 (79.4%) to Era 2 (87.8%), and Era 3 (87%) (p = 0.004), while rates of death before HTx decreased (Era 1 = 17.7%; Era 2 = 11%, Era 3 = 12.4%; p = 0.037) Median time from listing to HTx increased in patients supported with intra-aortic balloon pumps (Era 1 = 8 days, Era 2 = 15 days; p < 0.001) but remained stable in other candidates (Era 1 = 6 days; Era 2 = 5 days; Era 3 = 6 days; p = 0.134). One-year post-transplant survival was 71.4% in Era 1, 79.3% in Era 2, and 76.5% in Era 3 (p = 0.112). Preoperative bridging with ECMO was associated with increased 1-year post-transplant mortality (adjusted HR=1.71; 95% CI 1.15-2.53; p = 0.008).

CONCLUSIONS

During the period 2010 to 2020, successive changes in the Spanish organ allocation protocol were followed by a significant increase of the rate of HTx and a significant reduction of waiting list mortality in candidates supported with temporary MCS. One-year post-transplant survival rates remained acceptable.

Incremental cost-effectiveness of extracorporeal membranous oxygenation as a bridge to cardiac transplant or left ventricular assist device placement in patients with refractory cardiogenic shock

Objective

Emerging literature has described using venoarterial extracorporeal membranous oxygenation (ECMO) as a bridge to transplant or left ventricular assist device (LVAD) placement. We sought to identify the incremental cost-effectiveness ratio (ICER) of ECMO used as a bridge to cardiac transplant or LVAD.

Methods

Patients with refractory cardiogenic shock who received venoarterial ECMO and were bridged to either cardiac transplant (n = 7) or a HeartMate 3 LVAD (n = 6) placement were included. Markov modeling was used, comparing ECMO bridging with non–ECMO-bridged patients. Cohorts entered the model alive and at every 1-year cycle, were exposed to risk of death, and ran forward for 20 years after transplant or LVAD.

Results

Patients bridged with ECMO to cardiac transplant were stratified as group 1 whereas those bridged with ECMO to LVAD were stratified as group 2. The average ECMO run was 3 days in group 1 versus 11 days in group 2. Among group 1 patients, the ICER was $246,629 but was paired with a longer life expectancy. The ICER of group 2 patients was –$107,088 and was not paired with a longer life expectancy. The average inpatient cost for group 1 was found to be $636,023 versus $769,471 for group 2 patients. The average inpatient costs for patients not bridged to ECMO who received cardiac transplant or LVAD was $538,928 and $325,242, respectively.

Conclusions

Using ECMO to bridge to transplant or LVAD placement is not cost effective. However, patients bridged to transplant are paired with longer life expectancy in contrast to patients bridged to LVAD.

Post Heart Transplantation Outcomes of Patients Supported on Biventricular Mechanical Support

With the implementation of the new heart transplant (HT) allocation system, patients requiring biventricular support systems have the highest priority, a shorter waitlist time, and a higher frequency of HT. However, the short-term and long-term outcomes of such patients are often disputed. Hence, we examined the outcomes of these patients who underwent HT before change in allocation scheme. Additionally, we compared post-HT outcomes of extracorporeal membrane oxygenation (ECMO) with other nondischargeable biventricular (BiVAD) supported patients. We identified adult ECMO or BiVAD supported HT recipients between 2000 and 2018 in the Scientific Registry of Transplant Recipients database. We compared survival with the Kaplan-Meier method. Using overlap propensity score weighting, we constructed Cox proportional hazards regression models to determine the risk-adjusted influence of BiVAD versus ECMO on survival. Of the 730 patients HT recipients; 528 (72.3%) and 202 (27.7%) were bridged with BiVAD and ECMO, respectively. For BiVAD versus ECMO patients, the 30-day, 1-year, 3-year, and 5-year mortality rates were 8.0% versus 14.4%, 16.3% versus 21.3%, 22.4% versus 25.3%, and 26.3% versus 25.7%, respectively. Risk-adjusted post-HT survival of BiVAD and ECMO patients at 30-day (HR 1.24 [95% CI, 0.68-2.27]; P = 0.4863), 1-year (HR 1.29 [95% CI, 0.80-2.09]; P = 0.3009), 3-year (HR 1.27 [95% CI, 0.83-1.94]; P = 0.2801), and 5-year (HR 1.35, 95% CI, 0.90-2.05; P = 0.1501) were similar. Around three-fourth of the ECMO or BiVAD supported patients were alive at 5-years post-HT. The short-term and long-term post-HT survivals of groups were comparable.

Extracorporeal membrane oxygenation as a bridge to durable mechanical circulatory support or heart transplantation

BACKGROUND

Patients with cardiogenic shock may require extracorporeal membrane oxygenation (ECMO) prior to durable mechanical circulatory support (dMCS) or heart transplantation (HTx).

METHODS

We investigated the clinical characteristics and outcomes of adult patients with ECMO support as bridge to dMCS or HTx between 1/1/13 and 12/31/20.

RESULTS

Of 57 patients who underwent bridging ECMO, 41 (72%) received dMCS (approximately half with biventricular support) and 16 (28%) underwent HTx, 13 (81%) after the 2018 UNOS allocation system change. ECMO → HTx patients had shorter ventilatory time (3.5 vs 7.5 days; p = 0.018), ICU stay (6 vs 18 days; p = 0.001), and less need for inpatient rehabilitation (18.8% vs 57.5%; p = 0.016). The 1-year survival post HTx was 81.3% in the ECMO → HTx group and 86.4% in the ECMO → dMCS group (p = 0.11). For those patients in the ECMO → dMCS group who did not undergo HTx, 1-year survival was significantly lower, 31.6% (p = 0.001).

CONCLUSION

Patients on ECMO who undergo HTx, with or without dMCS bridge, have acceptable post-HTx survival. These findings suggest that HTx from ECMO is a viable option for carefully selected patients deemed acceptable to proceed with definitive advanced therapies, especially in the era of the new UNOS allocation system.

Clinical profile and in-hospital outcome of patients supported by intra-aortic balloon pump in the clinical setting of cardiogenic shock

Background

Despite controversial evidences, intra-aortic balloon pump (IABP) is still the most widely used temporary mechanical support device in cardiogenic shock (CS), as a bridge to recovery or to more invasive mechanical supports/heart transplantation.

Methods

We analyzed retrospectively data of all patients receiving IABP for CS from 2009 to 2018 in a referral centre for advanced heart failure and heart transplantation; we included CS following acute coronary syndrome (ACS) and other CS etiologies different from ACS. We excluded patients in which IABP was implanted as a support following cardiac surgery, non-cardiac surgery in patients with severe chronic heart failure, or in elective high risk or complicated Cath Lab procedures.We focused on in-hospital outcomes (including death, recovery, heart transplantation, LVAD) and IABP complications.

Results

403 patients received IABP, 303 (75.2%) following ACS and 100 (24.8%) in non-ACS CS. Non-ACS patients were younger (59 ± 18.3 vs 73.1 ± 12.6 years, p < 0.001), had lower median left ventricular ejection fraction (LVEF) (25% [18-35] vs 38% [25-45], p < 0.001). In patients with non-ACS etiologies IABP was more frequently a bridge to heart transplantation [20% (n = 20) vs 0.3% (n = 1), P < 0.001] or LVAD [4% (n = 4) vs 0.6% (n = 2), P = 0.055], while ACS patients were more frequently discharged without transplantation/LVAD [65.7% (n = 199) vs 33% (n = 33), P < 0.001]. Non-ACS patients showed higher in-hospital mortality [46% (n = 46) vs 33.9% (n = 103), P = 0.042]. Post-transplant/LVAD outcome in non-ACS subgroup was favorable (21 out of 24 patients were discharged). Serious IABP-related adverse events occurred in 21 patients (5.2%). Ischemic/hemorrhagic complications, infections and thrombocytopenia were more frequent with longer IABP stay.

Conclusions

Despite therapy including percutaneous circulatory support, mortality in CS is still high. In our experience, in the clinical setting of refractory CS an IABP support represents a relatively safe circulatory support, associated with a low rate of serious complications in complex clinical scenarios.

Impact of using higher-risk donor hearts for candidates with pre-transplant mechanical circulatory support

BACKGROUND

We evaluated post-heart transplant (HTx) outcomes after use of higher-risk donor hearts for candidates supported with pre-HTx mechanical circulatory support (MCS).

METHODS

In this retrospective analysis of the national United Network for Organ Sharing registry, a total of 9,915 adult candidates on MCS underwent HTx from January 1, 2010 to March 31, 2019. Multi-organ, re-transplant, and congenital heart disease patients were excluded. Higher-risk donor organs met at least one of the following criteria: left ventricular ejection fraction <50%, donor to recipient predicted heart mass ratio <0.86, donor age >55 years, or ischemic time >4 hours. Primary outcome was 1 year post-transplant survival.

RESULTS

Among HTx recipients, 3688 (37.2%) received higher-risk donor hearts. Candidates supported with pre-HTx extracorporeal membrane oxygenation or biventricular assist device (n = 374, 3.8%) who received higher-risk donor hearts had comparable 1 year survival (HR: 1.14, 95% CI: [0.67-1.93], p = 0.64) to recipients of standard-risk donor hearts, when adjusted for recipient age and sex. In candidates supported with intra-aortic balloon pump (n = 1391, 14.6%), transplantation of higher-risk donor hearts did not adversely affect 1 year survival (HR: 0.80, 95% CI: [0.52-1.22], p = 0.30). Patients on durable left ventricular assist devices (LVAD) who received higher-risk donor hearts had comparable 1 year survival to continued LVAD support on the waitlist, but mortality was increased compared to those who received standard-risk donor hearts (HR: 1.37, 95% CI: [1.11-1.70], p = 0.004).

CONCLUSIONS

Patients requiring pre-HTx temporary MCS who received higher-risk donor hearts had comparable 1 year post-transplant survival to those who received standard-risk donor hearts. Stable patients on durable LVADs may benefit from waiting for standard-risk donor hearts.

Impact of mechanical circulatory support on post-transplant stroke risk

The effect of type of mechanical circulatory support on stroke risk during the early post-transplant period remains undefined in patients bridged to transplant. This study assesses if the type of circulatory support device affects stroke risk in this population. The study cohort of 4257 adult patients bridged with mechanical support to cardiac transplant were derived from the UNOS transplant registry data. Risk factors assessed were age, gender, ischemic time, diabetes (recipient), durable mechanical support at listing and mechanical ventilation pre-transplant. Descriptive statistics were used to describe characteristics of the study cohort. Univariate logistic regression was used to test if there is a significant association between stroke event and all the potential risk factors. Multivariate logistic regression was used to test such associations while adjusting for all other risk factors. Odds ratios (ORs) and their 95% confidence intervals (CIs) in parenthesis, were calculated. p < 0.05 was considered significant. Patients on Extracorporeal membrane oxygenation (ECMO) had the highest risk of stroke immediately post-transplant prior to discharge (OR 3.03, {1.16, 7.95}) followed by Total Artificial Heart (TAH) (OR 2.03, {1.01, 4.07) as compared to those only on a Left Ventricular Assist Device (LVAD). Ischemic time (OR 1.3 {1.09, 1.45}) and diabetes (OR 1.8 {1.29, 2.51}) were significant risk factors. Patients on ECMO and TAH had a 203% and 103% increase respectively in the odds of having a stroke prior to discharge as compared to those only on LVADS.

Veno-arterial Extracorporeal Membrane Oxygenation as Bridge to Heart Transplantation: The Way Forward

Advanced heart failure (HF) represents a public health priority due to the increase of affected patients and the meaningful mortality. Durable mechanical circulatory support (MCS) and heart transplantation (HTx) are unique therapies for end-stage HF (ESHF), with positive early and long-term outcomes. The patients who underwent HTx have a 1-y survival of 91% and a median survival of 12-13 y, whereas the median survival of ESHF is <12 mo. Short-term MCS with veno-arterial extracorporeal membrane oxygenation (VA ECMO) can be used as a bridge to transplantation strategy. Patients bridged with VA ECMO have significantly lower survival in comparison with non-MCS bridged and left ventricular assist device-bridged patients. VA ECMO represents an effective, and sometimes unique, system to obtain rapid hemodynamic stabilization, but possible negative effects on patients' outcomes after HTx must be considered. Here, we discuss the use of VA ECMO as bridge to transplantation.

Bridging With Extracorporeal Membrane Oxygenation Under the New Heart Allocation System: A United Network for Organ Sharing Database Analysis

BACKGROUND

The effect of the new donor heart allocation system on survival following bridging to transplantation with venous-arterial extracorporeal membrane oxygenation remains unknown. The new allocation system places extracorporeal membrane oxygenation-supported candidates at the highest status.

METHODS

The United Network for Organ Sharing database was queried for adults bridged to single-organ heart transplantation with extracorporeal membrane oxygenation from October 2006 to February 2020. Association between implementation of the new system and recipient survival was analyzed using Kaplan-Meier estimates, Cox proportional hazards models, and propensity score matching.

RESULTS

Of 364 recipients included, 173 and 191 were transplanted under new and old systems, respectively. Compared with the old system, waitlist time was halved under the new system (5 versus 10 days, P<0.01); recipients also demonstrated lower rates of prior cardiac surgery (32.9% versus 44.5%, P=0.03) and preoperative ventilation (30.6% versus 42.4%, P=0.02). Unadjusted 180-day survival was 90.2% (95% CI, 84.7%-94.2%) and 69.6% (95% CI, 62.6%-76.1%) under the new and old systems, respectively. Cox proportional hazards analysis demonstrated listing and transplantation under the new system to be an independent predictor of post-transplant survival (adjusted hazard ratio, 0.34 [95% CI 0.20-0.59]). Propensity score matching demonstrated a similar trend (hazard ratio, 0.36 [95% CI, 0.19-0.66]). Candidates listed under the new system were significantly less likely to experience waitlist mortality or deterioration (subhazard ratio, 0.38 [95% CI, 0.25-0.58]) and more likely to survive to transplant (subhazard ratio, 4.29 [95% CI, 3.32-5.54]).

CONCLUSIONS

Recipients transplanted following extracorporeal membrane oxygenation bridging to transplantation under the new system achieve greater 180-day survival compared with the old and demonstrate less preoperative comorbidity. Waitlist outcomes have also improved significantly under the new allocation system.

Primary Graft Dysfunction After Isolated Heart Transplantation - Incidence, Risk Factors, and Clinical Implications Based on a Single-Center Experience

BACKGROUND

Since the international consensus on primary graft dysfunction (PGD) following heart transplantation (HT) was reported in 2014, few clinical studies have been reported. We aimed to analyze the incidence, predictive factors, and clinical implications of PGD following the International Society of Heart and Lung Transplant criteria in a single center.Methods and Results:This study enrolled 570 consecutive adult patients undergoing isolated HT between November 1992 and December 2017. Under a new set of criteria, PGD-left ventricle (PGD-LV) occurred in 35 patients (6.1%; mild, n=1 [0.2%]; moderate, n=14 [2.5%]; severe, n=20 [3.5%]), whereas PGD-right ventricle (PGD-RV) occurred in 3 (0.5%). Multivariable analysis demonstrated that preoperative admission (odds ratio [OR] 4.20; 95% confidence interval [CI] 1.24-14.26; P=0.021), preoperative extracorporeal membrane oxygenation (OR 4.03; 95% CI 1.75-9.26; P=0.001), and prolonged total ischemic time (OR 1.09; 95% CI 1.02-1.15; P=0.006) were significant predictors of moderate to severe PGD-LV. Moderate to severe PGD-LV was an independent and significant risk factor for early death (OR 55.64; 95% CI 11.65-265.73; P<0.001), with its effects extending up to 3 months after HT.

CONCLUSIONS

Moderate to severe PGD-LV, as defined by the new guidelines, is an important predictor of early mortality, with effects extending up to 3 months after HT. Efforts to reduce the occurrence of moderate to severe PGD-LV may lead to better outcomes.

Removing administrative boundaries using a gravity model for a national liver allocation system

Geographic disparities emerged as an increasing issue in organ allocation policies. Because of the sequential and discrete geographical models used for allocation scores, artificial regional boundaries may impede the access of candidates with the greatest medical urgency to vital organs. This article describes a continuous geographical allocation model that provides accurate organ access by introducing a multiplicative interaction between the patient's condition and the distance to the graft by using a gravity model. Patients with the most urgent need will thus have access to organs from farther away, while those in less urgent need may only have access to organs geographically closer. Compared to the previous French liver allocation scheme, the gravity model precluded transplantations for candidates with a Model for End-Stage Liver Disease (MELD) ≤ 14 for decompensated cirrhosis from 10.3% to 0.6%. Death and delisting while on the waiting list at 1 year also decreased from 30.1% to 22.4% for MELD ≥ 35. Waiting list (cumulative hazard ratio (CHR)  0.84 after adjustment) and posttransplant survival improved significantly (hazard ratio = 0.83 after adjustment). This new liver allocation system provides more equitable access to liver transplants and an efficient and safe alternative to administrative boundaries for geographical models in organ allocation.

Infectious complications associated with short-term mechanical circulatory support in urgent heart transplant candidates

INTRODUCTION AND OBJECTIVES

Short-term mechanical circulatory support is frequently used as a bridge to heart transplant in Spain. The epidemiology and prognostic impact of infectious complications in these patients are unknown.

METHODS

Systematic description of the epidemiology of infectious complications and analysis of their prognostic impact in a multicenter, retrospective registry of patients treated with short-term mechanical devices as a bridge to urgent heart transplant from 2010 to 2015 in 16 Spanish hospitals.

RESULTS

We studied 249 patients, of which 87 (34.9%) had a total of 102 infections. The most frequent site was the respiratory tract (n=47; 46.1%). Microbiological confirmation was obtained in 78 (76.5%) episodes, with a total of 100 causative agents, showing a predominance of gram-negative bacteria (n=58, 58%). Compared with patients without infection, those with infectious complications showed higher mortality during the support period (25.3% vs 12.3%, P=.009) and a lower probability of receiving a transplant (73.6% vs 85.2%, P=.025). In-hospital posttransplant mortality was similar in the 2 groups (with infection: 28.3%; without infection: 23.4%; P=.471).

CONCLUSIONS

Patients supported with temporary devices as a bridge to heart transplant are exposed to a high risk of infectious complications, which are associated with higher mortality during the organ waiting period.

Outcomes from adult veno-arterial extracorporeal membrane oxygenation in a cardiovascular disease center from 2009 to 2019

INTRODUCTION

Extracorporeal membrane oxygenation (ECMO) is an imperative short-term cardiopulmonary support device now. We aimed to provide a single-center experience of veno-arterial (V-A) ECMO management and identify the risk factors of in-hospital mortality.

METHODS

We conducted a retrospective review of adult patients who received V-A ECMO between 2009 and 2019 in a cardiovascular disease center. The risk factor analysis of in-hospital mortality was conducted.

RESULTS

The study reviewed 236 patients, with an overall survival rate of 68.2%. The survivors' blood lactate concentration is significantly lower than non-survivors [7.4 (7.8) vs 11.1 (9.7), p = 0.002]. Patients who received heart transplantation were with higher in-hospital survival rate. Survivors developed less hepatic dysfunction, acute kidney injury and myocardial damage [23 (14.3%) vs 19 (25.3%), p = 0.039; 81 (50.3%) vs 51 (68%), p = 0.011; 24 (14.9%) vs 22 (29.3%), p = 0.009, respectively], with higher rate of continuous renal replacement therapy (CRRT) [56 (34.8%) vs 53 (70.7%), p < 0.001]. Fewer survivors' 24 hours and total chest drainage was over 1000 mL, and the rate of re-exploration as well as red blood cell and platelet transfusion were lower in survivors. In multivariate analysis, female, pre-ECMO blood lactate concentration, hyperlipidemia, CRRT, and 24 hours chest drainage ⩾ 1000 mL were risk factors of early mortality.

CONCLUSIONS

By providing a general description of V-A ECMO practice at a single-center in China. Post-heart transplant graft failure was associated with numerically, the greatest survival in our practice. Furthermore, female sex, pre-ECMO blood lactate concentration, hyperlipidemia, CRRT, and high blood loss in chest drains are predictors of mortality in patients who undergo V-A ECMO.

Statistical performance of 16 posttransplant risk scores in a contemporary cohort of heart transplant recipients

Accurate risk stratification of early heart transplant failure is required to avoid futile transplants and rationalize donor selection. We aimed to evaluate the statistical performance of existing risk scores on a contemporary cohort of heart transplant recipients. After an exhaustive search, we identified 16 relevant risk scores. From the UNOS database, we selected all first noncombined adult heart transplants performed between 2014 and 2017 for validation. The primary endpoint was death or retransplant during the first year posttransplant. For all scores, we analyzed their association with outcomes, sensitivity, specificity, likelihood ratios, and discrimination (concordance index and overlap of individual scores). The cohort included 9396 patients. All scores were significantly associated with the primary outcome (P < .001 for all scores). Their likelihood ratios, both negative and positive, were poor. The discriminative performance of all scores was limited, with concordance index ranging from 0.544 to 0.646 (median 0.594) and an important overlap of individual scores between patients with or without the primary endpoint. Subgroup analyses revealed important variation in discrimination according to donor age, recipient age, and the type of assist device used at transplant. Our findings raise concerns about the use of currently available scores in the clinical field.

Impact of bridge-to-bridge strategies from paracorporeal to implantable left ventricular assist devices on the pre-heart transplant outcome: A single-center analysis of 134 cases

BACKGROUND

In Japan, patients with heart failure who have a paracorporeal left ventricular assist device (pLVAD) and cannot be weaned from the VAD may undergo conversion to implantable continuous-flow LVAD (iLVAD) via a bridge-to-bridge (BTB) strategy for bridge-to-transplantation (BTT). This study aimed to evaluate the real-world clinical status of BTB strategies.

METHODS

Among 134 patients who underwent iLVAD implantation for BTT, 34 patients underwent conversion from pLVAD to iLVAD (BTB group) and 100 patients underwent iLVAD implantation primarily (primary iLVAD group). The clinical characteristics and outcomes were compared between the two groups.

RESULTS

No significant difference was found in the overall survival between the two groups (p = 0.26; log-rank test). However, the 1-year survival rate and the 1-year freedom from the composite events of death, stroke, systemic infection, and bleeding rate were lower in the BTB group than in the primary iLVAD group (survival rate, 88.2% vs. 99.0%, p = 0.0040; composite event-free survival rate, 26.1% vs. 49.8%, p = 0.030; log-rank test). Multivariate analysis indicated that the BTB strategy [hazard ratio (HR) 1.70, 95% confidence intervals (CI) 1.03-2.72; p=0.036] and serum total bilirubin levels at iLVAD implantation [HR 1.31, 95% CI 1.00-1.65; p=0.043] were independent predictors of 1-year composite events.

CONCLUSIONS

The BTB strategy is useful in providing long-term survival in patients with acute critical diseases. However, the early mortality rate after conversion is higher in patients who underwent the BTB strategy.

Extracorporeal membrane oxygenation bridge to heart transplant: Trends following the allocation change

BACKGROUND

This study compared outcomes of patients bridged with extracorporeal membrane oxygenation (ECMO) to orthotopic heart transplantation (OHT) following the recent heart allocation policy change.

METHODS

The United Network of Organ Sharing Registry (UNOS) database was queried to examine OHT patients between 2010 and 2020 that were bridged with ECMO. Waitlist outcomes and 1-year posttransplant survival were compared between patients waitlisted and/or transplanted before and after the heart allocation policy change. Secondary outcomes included posttransplant stroke, renal failure, and 1-year rejection.

RESULTS

A total of 285 waitlisted patients were included, 173 (60.7%) waitlisted under the old policy and 112 (39.3%) under the new policy. New policy patients were more likely to receive OHT (82.2% vs. 40.6%), and less likely to be removed from the waitlist due to death or clinical deterioration (15.0% vs. 41.3%; both p < .001). A total of 165 patients bridged from ECMO to OHT were analyzed, 72 (43.6%) transplanted during the old policy and 93 (56.3%) under the new. Median waitlist time was reduced under the new policy (4 days [interquartile range {IQR}: 2-6] vs. 47 days [IQR: 10-228]). Postoperative renal failure was higher in the new policy group (23% vs. 6%; p = .002), but rates of stroke and 1-year acute rejection were equivalent. One-year survival was lower the new policy but was not significant (79.8% vs. 90.3%; p = .3917).

CONCLUSIONS

The UNOS heart allocation policy change has resulted in decreased waitlist times and higher likelihood of transplant in patients supported with ECMO. Posttransplant 1-year survival has remained comparable although absolute rates are lower.

Outcomes in the 2018 UNOS donor heart allocation system: A perspective on disparate analyses

The United Network for Organ Sharing (UNOS) implemented a revised donor heart allocation system on October 18, 2018 with principle aims to reduce waitlist mortality, enhance geographic organ sharing, and improve organ distribution equity. Five recently published analyses compared outcomes of heart transplant (HT) recipients transplanted under the revised versus previous system. All demonstrated increased pre-transplant temporary mechanical circulatory support use and graft ischemic times under the revised system. However, despite using data from the same UNOS Registry, three analyses demonstrated increased risk of post-transplant mortality under the revised system, while two others found no significant difference in mortality risk. These studies differed in their analytic cohorts, study periods, follow-up duration, and statistical methodologies. Additionally, some may have introduced survivor bias or violated non-informative censoring. Given these variable findings, longer-term outcome assessment is warranted before the HT community can truly understand the impact of the 2018 UNOS system revision on post-transplant outcomes.

Management of nonischemic-dilated cardiomyopathies in clinical practice: a position paper of the working group on myocardial and pericardial diseases of Italian Society of Cardiology

: Nonischemic-dilated cardiomyopathy (NIDCM) is an entity that gathers extremely heterogeneous diseases. This awareness, although leading to continuous improvement in survival, has increased the complexity of NIDCM patients' management. Even though the endorsed 'red-flags' approach helps clinicians in pursuing an accurate etiological definition in clinical practice, it is not clear when and how peripheral centers should interact with referral centers with specific expertise in challenging scenarios (e.g. postmyocarditis and genetically determined dilated cardiomyopathy) and with easier access to second-line diagnostic tools and therapies. This position paper will summarize each step in NIDCM management, highlighting the multiple interactions between peripheral and referral centers, from first-line diagnostic workup and therapy to advanced heart failure management and long-term follow-up.

New French heart allocation system: Comparison with Eurotransplant and US allocation systems

Graft allocation rules for heart transplantation are necessary because of the shortage of heart donors, resulting in high waitlist mortality. The Agence de la biomédecine is the agency in charge of the organ allocation system in France. Assessment of the 2004 urgency-based allocation system identified challenging limitations. A new system based on a score ranking all candidates was implemented in January 2018. In the revised system, medical urgency is defined according to candidate characteristics rather than the treatment modalities, and an interplay between urgency, donor-recipient matching, and geographic sharing was introduced. In this article, we describe in detail the new allocation system and compare these allocation rules to Eurotransplant and US allocation policies.

Favorable Outcomes of a Direct Heart Transplantation Strategy in Selected Patients on Extracorporeal Membrane Oxygenation Support

OBJECTIVES

Heart transplantation in patients supported by venoarterial extracorporeal membrane oxygenation has been associated with poor prognosis. A specific protocol for extracorporeal membrane oxygenation management encompassing patient selection, implantation strategy, and preoperative and perioperative treatment is applied at our institution. Our aim was to compare posttransplant outcomes of patients supported or not by extracorporeal membrane oxygenation at the time of heart transplantation.

DESIGN

A large observational single-center retrospective study was conducted. The primary endpoint was overall survival after heart transplantation. Secondary endpoints included death-censored rejection-free survival and the frequency of extracorporeal membrane oxygenation-related complications.

SETTING

One heart transplantation and extracorporeal membrane oxygenation high-volume center.

PATIENTS

All consecutive patients over 18 years old with a first noncombined heart transplantation performed between 2012 and 2016 were included.

INTERVENTIONS

None (retrospective observational study).

MEASUREMENTS AND MAIN RESULTS

Among the 415 transplanted patients, 118 (28.4%) were on extracorporeal membrane oxygenation at the time of transplantation (peripheral, 94%; intrathoracic, 6%). Median time on extracorporeal membrane oxygenation before heart transplantation was 9 days (interquartile range, 5-15 d) and median follow-up post heart transplantation was 20.7 months. Posttransplant survival did not differ significantly between the two groups (1-yr survival = 85.5% and 80.7% in extracorporeal membrane oxygenation vs nonextracorporeal membrane oxygenation patients; hazard ratio, 0.69; 95% CI, 0.43-1.11; p = 0.12, respectively). Donor age, body mass index, creatinine clearance, and ischemic time were independently associated with overall mortality, but not extracorporeal membrane oxygenation at the time of heart transplantation. Rejection-free survival also did not significantly differ between groups (hazard ratio, 0.85; 95% CI, 0.60-1.23; p = 0.39). Local wound infection was the most frequent complication after extracorporeal membrane oxygenation (37% of patients).

CONCLUSIONS

With the implementation of a specific protocol, patients bridged to heart transplantation on extracorporeal membrane oxygenation had similar survival compared with those not supported by extracorporeal membrane oxygenation.

What are the results of venoarterial extracorporeal membrane oxygenation bridging to heart transplantation?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether heart transplantation is a viable treatment option in patients in refractory cardiogenic shock who could not be weaned off venoarterial extracorporeal membrane oxygenation (VA ECMO). Altogether, 373 papers were found using the reported search, of which 7 papers represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Evidence is derived from 3 papers based on registry analysis, 1 multi-institutional study and 3 single-institution reviews. Early post-transplant mortality of ECMO-bridged recipients ranges from 18.7% to 33.3% and 1-year survival from 44.6% to 72.0%. High acuity of recipient illness reflected by poor renal function, mechanical ventilation, advanced age, elevated serum lactate predict inferior outcome. We conclude that heart transplantation results in patients bridged with VA ECMO are inferior when compared to published outcome of non-bridged recipients. In the era of severe organ shortage and intense public and regulatory scrutiny of the results, the decision to transplant a patient directly of VA ECMO needs to be made on a case-by-case basis. Potential gain in decreasing the waiting list mortality of these critically ill patients needs to be weighed against poorer post-transplantation mortality rates and mid- and long-term outcomes.

Venoarterial extracorporeal membrane oxygenation with or without simultaneous intra-aortic balloon pump support as a direct bridge to heart transplantation: results from a nationwide Spanish registry

OBJECTIVES

To investigate the potential clinical benefit of an intra-aortic balloon pump (IABP) in patients supported with venoarterial extracorporeal membrane oxygenation (VA-ECMO) as a bridge to heart transplantation (HT).

METHODS

We studied 169 patients who were listed for urgent HT under VA-ECMO support at 16 Spanish institutions from 2010 to 2015. The clinical outcomes of patients under simultaneous IABP support (n = 73) were compared to a control group of patients without IABP support (n = 96).

RESULTS

There were no statistically significant differences between the IABP and control groups with regard to the cumulative rates of transplantation (71.2% vs 81.2%, P = 0.17), death during VA-ECMO support (20.6% vs 14.6%, P = 0.31), transition to a different mechanical circulatory support device (5.5% vs 5.2%, P = 0.94) or weaning from VA-ECMO support due to recovery (2.7% vs 0%, P = 0.10). There was a higher incidence of bleeding events in the IABP group (45.2% vs 25%, P = 0.006; adjusted odds ratio 2.18, 95% confidence interval 1.02-4.67). In-hospital postoperative mortality after HT was 34.6% in the IABP group and 32.5% in the control group (P = 0.80). One-year survival after listing for urgent HT was 53.3% in the IABP group and 52.2% in the control group (log rank P = 0.75). Multivariate adjustment for potential confounders did not change this result (adjusted hazard ratio 0.94, 95% confidence interval 0.56-1.58).

CONCLUSIONS

In our study, simultaneous IABP therapy in transplant candidates under VA-ECMO support did not significantly reduce morbidity or mortality.

Evaluation of Risk Factors for Heart-Lung Transplant Recipient Outcome: An Analysis of the United Network for Organ Sharing Database

BACKGROUND

Heart-lung transplantation (HLTx) is an effective treatment for patients with advanced cardiopulmonary failure. However, no large multicenter study has focused on the relationship between donor and recipient risk factors and post-HLTx outcomes. Thus, we investigated this issue using data from the United Network for Organ Sharing database.

METHODS

All adult patients (age ≥18 years) registered in the United Network for Organ Sharing database who underwent HLTx between 1987 and 2017 were included (n=997). We stratified the cohort by patients who were alive without retransplant at 1 year (n=664) and patients who died or underwent retransplant within 1 year of HLTx (n=333). The primary outcome was the influence of donor and recipient characteristics on 1-year post-HLTx recipient death or retransplant. Kaplan-Meier curves were created to assess overall freedom from death or retransplant. To obtain a better effect estimation on hazard and survival time, the parametric Accelerated Failure Time model was chosen to perform time-to-event modeling analyses.

RESULTS

Overall graft survival at 1-year post-HLTx was 66.6%. Of donors, 53% were male, and the mean age was 28.2 years. Univariable analysis showed advanced donor age, recipient male sex, recipient creatinine, recipient history of prior cardiac or lung surgery, recipient extracorporeal membrane oxygenation support, transplant year, and transplant center volume were associated with 1-year post-HLTx death or retransplant. On multivariable analysis, advanced donor age (hazard ratio [HR], 1.017; P=0.0007), recipient male sex (HR, 1.701; P=0.0002), recipient extracorporeal membrane oxygenation support (HR, 4.854; P<0.0001), transplant year (HR, 0.962; P<0.0001), and transplantation at low-volume (HR, 1.694) and medium-volume centers (HR, 1.455) in comparison with high-volume centers (P=0.0007) remained as significant predictors of death or retransplant. These predictors were incorporated into an equation capable of estimating the preliminary probability of graft survival at 1-year post-HLTx on the basis of preoperative factors alone.

CONCLUSIONS

HLTx outcomes may be improved by considering the strong influence of donor age, recipient sex, recipient hemodynamic status, and transplant center volume. Marginal donors and recipients without significant factors contributing to poor post-HLTx outcomes may still be considered for transplantation, potentially with less impact on the risk of early postoperative death or retransplant.

Physical therapy in successful venoarterial extracorporeal membrane oxygenation bridge to orthotopic heart transplantation

BACKGROUND

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is a temporary mechanical circulatory support system that may be used as a lifesaving therapy for patients in acute heart failure and as a bridge to definitive management. Physical therapy in these patients remains challenging, with limited protocols to guide practitioners.

METHODS

We describe a case of a 37-year-old gentleman who presented with familial cardiomyopathy and cardiogenic shock.

RESULTS

Our patient underwent urgent peripheral venoarterial extracorporeal membrane oxygenation (VA-ECMO) followed by successful heart transplantation. While on ECMO support he was enrolled in a physical therapy program that included the VitalGo Tilt Bed to improve lower body weight bearing while avoiding hip flexion and damage to the peripheral ECMO cannulae. The patient was discharged home expeditiously after heart transplant due to aggressive physical rehabilitation while on full VA-ECMO support.

CONCLUSIONS

Early intensive physical rehabilitation is feasible and safe and may result in improved outcomes and expeditious discharge in VA ECMO patients. Protocol driven multidisciplinary physical therapy with a patient on femorally cannulated VA-ECMO retains the advantages of lower extremity peripheral cannulation while eliminating the risks of immobility. The new UNOS allocation system may result in a successful bridge to transplantation in patients on VA-ECMO due to the increased prioritization of this population to receive donor organs.

Five years' experience with a peripheral veno-arterial ECMO for mechanical bridge to heart transplantation

Background

Mechanical circulatory support (MCS) is the only way to save a life for heart transplant candidates and to decrease of waiting list mortality. The choice between short- or long-term pretransplant MCS depends on of type and severity of CHF. One of the most frequently used methods of temporary MSC before orthotopic heart transplantation (OHTx) is veno-arterial extracorporeal membrane oxygenation (VA ECMO). The aim of this study was to analyze own experience of peripheral VA ECMO (pVA ECMO) in heart transplant candidates needed in urgent HT.

Methods

This study included 182 pts [160 (87.9%) men and 22 (12.1%) female, age 43±1.2 yrs] supported with pVA ECMO in the period from 01. 01. 2013 to 31. 12. 2017 or 23.2% from all waiting list (n=786).

Results

During VA ECMO, 16 (8.8%) of the 182 pts died. In most pts [n=13 (81.3%)] multiorgan failure/sepsis were the cause of death. One hundred and sixty-six (91.2%) pts were successfully bridged to OHTx or 27.9% from all heart transplant recipients (n=594) (2013-2017 yrs). The duration of pVA ECMO before OHTx (n=166) was 5.8±3.2 days. One hundred and forty-three (86.1%) from 166 pts were discharged to home. Post-transplant survival among heart transplant recipient with pre-transplant MCS by pVA ECMO was in comparison with recipients without pretransplant MCS [84.2% vs. 90.1% (6 months), 83.3% vs. 91.8% (1 years), 75.1% vs. 86.1% (2 years), 74.2% vs. 85.8% (3 years), 72.3% vs. 84.7% (4 years), 72.3% vs. 83.5% (5 years) respectively (P<0.0001)].

Conclusions

pVA ECMO is a useful tool of treatment of patients with INTERMACS profile 1/2. Results of OHTx at recipients bridged with VA ECMO are less successful that recipients without pre-transplant MCS. VA ECMO should be considered as a direct bridge to OHTx in conditions of limited financial resources of health care and high availability of donor's hearts.

VA-ECMO for cardiogenic shock in the contemporary era of heart transplantation: Which patients should be urgently transplanted?

With the impending United Network for Organ Sharing (UNOS) heart allocation policy giving VA-ECMO supported heart transplant (HT) candidates highest priority status (Tier 1), identifying patients in cardiogenic shock (CS) with severe and irreversible heart failure (HF) appropriate for urgent HT is critically important. In a center where wait times currently preclude this approach, we retrospectively reviewed 119 patients (ages 18-72) with CS from 1/2014 to 12/2016 who required VA-ECMO for >24 hours. Underlying aetiologies included postcardiotomy shock (45), acute coronary syndromes (33), and acute-on-chronic HF (16). Eighty-four percent of patients (100) had ≥1 contraindication to HT with 61.3% (73) having preexisting contraindications (eg, multiorgan dysfunction and substance abuse), and 68.1% (81) experienced preclusive complications (eg, renal failure, coagulopathy, and infection). Potential HT candidates were significantly more likely to survive to discharge (potential HT candidates 84.2% vs preexisting contraindications 43.8% vs contraindications developing on VA-ECMO 33.3%, P = 0.001). Among potential HT candidates, 11 (68.8%) were discharged without advanced therapies and 4 received durable left ventricular assist device (25.0%). Importantly, 1-year survival was 100% for the 11 patients with follow-up. Thus, further work is critical to define appropriate candidates for HT from VA-ECMO while avoiding preemptive transplantation in those with otherwise favorable outcomes.