Acute Kidney Injury After Heart Transplantation: Risk Factors and Clinical Outcomes

OBJECTIVE

Acute kidney injury (AKI) requiring renal-replacement therapy (RRT) after heart transplantation (OHT) is common and impairs outcomes. This study aimed to identify independent donor and recipient risk factors associated with RRT after OHT.

DESIGN

A retrospective data analysis.

SETTING

Data were collected from clinical routines in a maximum-care university hospital.

PARTICIPANTS

Patients who underwent OHT.

INTERVENTIONS

The authors retrospectively analyzed data from 264 patients who underwent OHT between 2012 and 2021; 189 patients were eligible and included in the final analysis.

MEASUREMENTS AND MAIN RESULTS

The mean age was 48.0 ± 12.3 years, and 71.4% of patients were male. Ninety (47.6%) patients were on long-term mechanical circulatory support (lt-MCS). Posttransplant AKI with RRT occurred in 123 (65.1%) patients. In a multivariate analysis, preoperative body mass index >25 kg/m² (odds ratio [OR] 4.74, p < 0.001), elevated preoperative creatinine levels (OR for each mg/dL increase 3.44, p = 0.004), administration of red blood cell units during transplantation procedure (OR 2.31, p = 0.041) and ischemia time (OR for each hour increase 1.77, p = 0.004) were associated with a higher incidence of RRT. The use of renin-angiotensin-aldosterone system blockers before transplantation was associated with a reduced risk of RRT (OR 0.36, p = 0.013). The risk of mortality was 6.9-fold higher in patients who required RRT (hazard ratio 6.9, 95% CI: 2.1-22.6 p = 0.001). Previous lt-MCS, as well as donor parameters, were not associated with RRT after OHT.

CONCLUSIONS

The implementation of guideline-directed medical therapy, weight reduction, minimizing ischemia time (ie, organ perfusion systems, workflow optimization), and comprehensive patient blood management potentially influences renal function and outcomes after OHT.

Employment Status Following Heart Transplantation: Data From the Danish Nationwide Social Service Payment Register During 20 years

Most studies on vocational rehabilitation after heart transplantation (HTX) are based on self-reported data. Danish registries include weekly longitudinal information on all public transfer payments. We intended to describe 20-year trends in employment status for the Danish heart-transplant recipients, and examine the influence of multimorbidity and socioeconomic position (SEP). Linking registry and Scandiatransplant data (1994-2018), we conducted a study in recipients of working age (19-63 years). The cohort contained 492 recipients (79% males) and the median (IQR) age was 52 years (43-57 years). Five years after HTX, 30% of the survived recipients participated on the labor market; 9% were in a flexible job with reduced health-related working capacity. Moreover, 60% were retired and 10% eligible for labor market participation were unemployed. Recipients with multimorbidity had a higher age and a lower prevalence of employment. Five years after HTX, characteristics of recipients with labor market participation were: living alone (27%) versus cohabitation (73%); low (36%) versus medium-high (64%) educational level; low (13%) or medium-high (87%) income group. Heart-transplant recipients with multimorbidity have a higher age and a lower prevalence of employment. Socioeconomically disadvantaged recipients had a lower prevalence of labor market participation, despite being younger compared with the socioeconomically advantaged.

Adherence to Pharmacotherapies After Heart Transplantation in Relation to Multimorbidity and Socioeconomic Position: A Nationwide Register-Based Study

No studies have examined the impact of multimorbidity and socioeconomic position (SEP) on adherence to the pharmacological therapies following heart transplantation (HTx). Using nationwide Danish registers, we tested the hypothesis that multimorbidity and SEP affect treatment patterns and adherence to pharmacological therapies in first-time HTx recipients. Pharmacological management included cost-free immunosuppressants and adjuvant medical treatment (preventive and hypertensive pharmacotherapies; loop diuretics). We enrolled 512 recipients. The median (IQR) age was 51 years (38-58 years) and 393 recipients (77%) were males. In recipients with at least two chronic diseases, prevalence of treatment with antihypertensive pharmacotherapies and loop diuretics was higher. The overall prevalence of adherence to treatment with tacrolimus or mycophenolate mofetil was at least 80%. Prevalence of adherence to preventive pharmacotherapies ranged between 65% and 95% and between 66% and 88% for antihypertensive pharmacotherapies and loop diuretics, respectively. In socioeconomically disadvantaged recipients, both the number of recipients treated with and adherence to cost-free everolimus, lipid modifying agents, angiotensin-converting enzyme/angiotensin II inhibitors, calcium channel blockers, and loop diuretics were lower. In recipients with multimorbidity, prevalence of treatment with antihypertensive pharmacotherapies and loop diuretics was higher. Among socioeconomically disadvantaged recipients, both number of patients treated with and adherence to cost-free everolimus and adjuvant pharmacotherapies were lower.

The Ability of Comorbidity Indices to Predict Mortality After Heart Transplantation: A Validation of the Danish Comorbidity Index for Acute Myocardial Infarction, Charlson Comorbidity Index, and Elixhauser Comorbidity Index

Advanced heart failure patients often have comorbidities of prognostic importance. However, whether total pretransplantation comorbidity burden predicts mortality in patients treated with heart transplantation (HTx) is unknown. We used population-based hospital and prescription data to examine the ability of the Danish Comorbidity Index for Acute Myocardial Infarction (DANCAMI), DANCAMI restricted to noncardiovascular diseases, Charlson Comorbidity Index, and Elixhauser Comorbidity Index to predict 30-d, 1-y, 5-y, and 10-y all-cause and cardiovascular mortality after HTx.

Methods

We identified all adult Danish patients with incident HTx from the Scandiatransplant Database between March 1, 1995, and December 31, 2018 (n = 563). We calculated Harrell's C-Statistics to examine discriminatory performance.

Results

The C-Statistic for predicting 1-y all-cause mortality after HTx was 0.58 (95% confidence interval [CI], 0.50-0.65) for a baseline model including age and sex. Adding comorbidity score to the baseline model did not increase the C-Statistics for DANCAMI (0.58; 95% CI, 0.50-0.65), DANCAMI restricted to noncardiovascular diseases (0.57; 95% CI, 0.50-0.64), Charlson Comorbidity Index (0.59; 95% CI, 0.51-0.66), or Elixhauser Comorbidity Index (0.58; 95% CI, 0.51-0.65). The results for 30-d, 5-y, and 10-y all-cause and cardiovascular mortality were consistent.

Conclusions

After accounting for patient age and sex, none of the commonly used comorbidity indices added predictive value to short- or long-term all-cause or cardiovascular mortality after HTx.

Individual-Level Socioeconomic Position and Long-Term Prognosis in Danish Heart-Transplant Recipients

Socioeconomic deprivation can limit access to healthcare. Important gaps persist in the understanding of how individual indicators of socioeconomic disadvantage may affect clinical outcomes after heart transplantation. We sought to examine the impact of individual-level socioeconomic position (SEP) on prognosis of heart-transplant recipients. A population-based study including all Danish first-time heart-transplant recipients (n = 649) was conducted. Data were linked across complete national health registers. Associations were evaluated between SEP and all-cause mortality and first-time major adverse cardiovascular event (MACE) during follow-up periods. The half-time survival was 15.6 years (20-year period). In total, 330 (51%) of recipients experienced a first-time cardiovascular event and the most frequent was graft failure (42%). Both acute myocardial infarction and cardiac arrest occurred in ≤5 of recipients. Low educational level was associated with increased all-cause mortality 10-20 years post-transplant (adjusted hazard ratio [HR] 1.95, 95% confidence interval [CI] 1.19-3.19). During 1-10 years post-transplant, low educational level (adjusted HR 1.66, 95% CI 1.14-2.43) and low income (adjusted HR 1.81, 95% CI 1.02-3.22) were associated with a first-time MACE. In a country with free access to multidisciplinary team management, low levels of education and income were associated with a poorer prognosis after heart transplantation.

Validation of cause of death classification after heart transplantation and cause-specific life expectancy compared to the general population

BACKGROUND

Post heart-transplant survival has increased, but information is lacking on specific causes of death and life expectancy. We aimed to assess cause-specific loss of life-years compared to the general population, evaluate classification for cause of death after heart transplantation, and assess validity of cause of death data from the International Society of Heart and Lung Transplant (ISHLT) registry.

METHODS

In this single center study, we included 239 heart recipients transplanted between 1988 and 2019 in Lund, Sweden (n = 239, 50% of the transplanted population where the cause of death was available). Two cardiologists retrospectively assigned causes of death according to a published classification (CLASS) in the 91 recipients who died during follow-up. Life expectancy was compared to data from the general population.

RESULTS

Compared to the average Swedish population, life expectancy for heart transplant recipients was 20 years shorter (IQR 12.9-27.2). The largest number of life-years lost were for deaths due to acute (49 years) and chronic rejection (27 years). Primary graft dysfunction (24 years) accounted for 24% of deaths, followed by malignancy (20 years) and infection (17 years), each accounting for ∼20% of deaths. Use of CLASS revealed moderate inter-rater agreement (56%) and moderate agreement with the ISHLT registry (62%).

CONCLUSIONS

Survival after heart transplantation was 20 years lower than in the general population. In the young, more life-years were lost due to acute graft rejection, whereas chronic graft rejection and primary graft failure were more important causes of death in older patients. Agreement was moderate between CLASS and the ISHLT registry classifications.

Diagnostic and Prognostic Value of a TDI-Derived Systolic Wall Motion Analysis as a Screening Modality for Allograft Rejection after Heart Transplantation

Background: Despite the risk for complications, allograft surveillance after orthotopic heart transplantation (OHT) is performed by cardiac catheterization and biopsies. We investigated the diagnostic and prognostic value of a TDI-derived systolic wall motion analysis of the posterobasal wall of the left ventricle (Sm) as a screening modality in OHT aftercare. Methods: We examined data of 210 eligible patients who underwent OHT between 2010 and 2020. Forty-four patients who had died within the initial hospital stay were excluded. For 166 patients, baseline and follow-up data were analyzed. The mean age at OHT was 46.2 (±11.4) years; 76.5% were male. Results: Within the observational period, 22 (13.3%) patients died. In total, 170 episodes of acute cellular or humoral rejections occurred (84 ISHLT1R; 13 ISHLT2R; 8 ISHLT3R; 65 AMR), and 29 catheterizations revealed cardiac allograft vasculopathy (5 CAV1; 4 CAV2; 20 CAV3). Individual Sm radial/longitudinal remained stable within the follow-up period (11.5 ± 2.2 cm/s; 10.9 ± 2.1 cm/s). Patients with acute rejections and CAV3 showed significant Sm radial/longitudinal reductions (AMR1: 1.6 ± 1.9 cm/s, confidence interval (CI) 0.77–0.243, p < 0.001; 1.8 ± 2.0 cm/s, CI 0.92–0.267, p < 0.001. ISHLT1R: 1.7 ± 1.8 cm/s, CI 1.32–2.08, p < 0.001; 2.0 ± 1.6 cm/s, CI 1.66–2.34, p < 0.001. CAV3: 1.3 ± 2.5 cm/s, CI 0.23–2.43, p < 0.017; 1.4 ± 2.8 cm/s, CI 0.21–2.66, p < 0.021). Lower Sm was associated with a threefold increase in all-cause mortality (hazard ratio (HR) 3.24, CI 1.2–8.76, p = 0.020; HR 2.92, CI 1.19–7.18, p = 0.019). Overall, Sm-triggered surveillance led to 0.75 invasive diagnostics per patient post-OHT year. Conclusions: Sm remained stable in the post-OHT course. Reductions indicated ISHLT1R, AMR1 and CAV3 and were associated with higher all-cause mortality. Sm-triggered surveillance may be referred to as a safe, high-yield screening modality in OHT aftercare.

Prognostic Factors of Renal Outcomes after Heart Transplantation: A Nationwide Retrospective Study

Renal dysfunction after heart transplantation (HT) is associated with poor survival. We investigated the predictive factors of renal outcomes after HT using nationwide cohort data. In this retrospective cohort study using the Health Insurance Review and Assessment database of Korea, 654 patients who received HT between 2008 and 2016 and survived until discharge after HT were analyzed. The median (interquartile range) age was 52 (40-60) years, and 68.1% were male. Perioperative renal replacement therapy (RRT) was performed in 27.8% of patients. During 2.8 years of median followup, end-stage kidney disease (ESKD) developed in 12 patients (1.8%). In a fully adjusted model, RRT > 3 weeks, the use of inotropes/vasopressors and non-use of ACEi/ARB were associated with ESKD. Preexisting renal disease tended to be associated with ESKD. Among the 561 patients without preexisting CKD, 104 (18.5%) developed chronic kidney disease (CKD). Age, extracorporeal membrane oxygenation, and RRT were associated with the development of CKD after HT. Our nationwide cohort study demonstrated that perioperative RRT was a predictor of poor renal outcomes after HT. These results suggest that an active renoprotective strategy is required during the perioperative period.

Clinical Factors Associated with Renal Outcome After Heart Transplantation

Cardiorenal syndrome (CRS) frequently occurs in end-stage heart failure patients waiting for heart transplantation (HT). Decision-making regarding simultaneous heart and kidney transplantation is an unresolved issue in these patients. We investigated clinical factors associated with renal outcome after HT. A total of 180 patients who received HT from 1996 to 2015 were included. Factors associated with early post-HT chronic kidney disease (CKD, estimated glomerular filtration rate [eGFR] < 60 mL/minute/1.73 m² within 1 year post-HT), post-HT end-stage kidney disease (ESKD), and significant renal function improvement (%ΔeGFR > 15%) at 1 year post-HT were analyzed. Early post-HT CKD and post-HT ESKD developed in 61 (33.9%) and 8 (4.4%) of 180 patients, respectively. Old age was only independently associated with early post-HT CKD and preexisting CKD tended to be associated with early post-HT CKD. Old age and preexisting CKD were independently associated with post-HT ESKD. Low pre-HT eGFR and preoperative renal replacement therapy were not associated with early post-HT CKD or post-HT ESKD. Young age, low pre-HT eGFR, and high %ΔeGFR 1 month post-HT were independently associated with significant renal function improvement. Preoperative renal function, including preoperative RRT, was not associated with post-HT mortality. In conclusion, preexisting CKD may impact renal outcomes after HT, but preoperative severe renal dysfunction, even that severe enough to require RRT, may not be a contraindication for HT alone. Our data suggest the necessity of early HT in end-stage heart failure patients with CRS and the importance of careful management during the early postoperative period.

Incidence, risk factors and clinical outcomes of acute kidney injury after heart transplantation: a retrospective single center study

Objectives

This study aimed to identify the incidence rate of Acute kidney injury (AKI) in our center and predict in-hospital mortality and long-term survival after heart transplantation (HTx).

Methods

This single-center, retrospective study from October 2009 and March 2020 analyzed the pre-, intra-, and postoperative characteristics of 95 patients who underwent HTx. AKI was defined according to the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Risk factors were analyzed by multivariable logistic regression models. The log-rank test was used to compare long-term survival.

Results

Thirty-three (34.7%) patients developed AKI. The mortality in hospital in HTx patients with and without AKI were 21.21 and 6.45%, respectively (P < 0.05). Recipients in AKI who required renal replacement therapy (RRT) had a hospital mortality rate of 43.75% compared to 6.45% in those without AKI or RRT (P < 0.0001). A long cardiopulmonary bypass (CPB) time (OR:11.393, 95% CI: 2.183 to 59.465, P = 0.0039) was positively related to the occurrence of AKI. A high intraoperative urine volume (OR: 0.031, 95% CI: 0.005 to 0.212, P = 0.0004) was negatively correlated with AKI. AKI requiring RRT (OR, 11.348; 95% CI, 2.418–53.267, P = 0.002) was a risk factor for mortality in hospital. Overall survival in patients without AKI at 1 and 3 years was not different from that in patients with AKI (P = 0.096).

Conclusions

AKI is common after HTx. AKI requiring RRT could contribute powerful prognostic information to predict mortality in hospital. A long CPB time and low intraoperative urine volume are associated with the occurrence of AKI.

Durable circulatory support with a paracorporeal device as an option for pediatric and adult heart failure patients

OBJECTIVES

Not all patients in need of durable mechanical circulatory support are suitable for a continuous-flow left ventricular assist device. We describe patient populations who were treated with the paracorporeal EXCOR, including children with small body sizes, adolescents with complex congenital heart diseases, and adults with biventricular failure.

METHODS

Information on clinical data, echocardiography, invasive hemodynamic measurements, and surgical procedures were collected retrospectively. Differences between various groups were compared.

RESULTS

Between 2008 and 2018, a total of 50 patients (21 children and 29 adults) received an EXCOR as bridge to heart transplantation or myocardial recovery. The majority of patients had heart failure compatible with Interagency Registry for Mechanically Assisted Circulatory Support profile 1. At year 5, the overall survival probability for children was 90%, and for adults 75% (P = .3). After we pooled data from children and adults, the survival probability between patients supported by a biventricular assist device was similar to those treated with a left ventricular assist device/ right ventricular assist device (94% vs 75%, respectively, P = .2). Patients with dilated cardiomyopathy had a trend toward better survival than those with other heart failure etiologies (92% vs 70%, P = .05) and a greater survival free from stroke (92% vs 64%, P = .01). Pump house exchange was performed in nine patients due to chamber thrombosis (n = 7) and partial membrane rupture (n = 2). There were 14 cases of stroke in eleven patients.

CONCLUSIONS

Despite severe illness, patient survival on EXCOR was high, and the long-term overall survival probability following heart transplantation and recovery was advantageous. Treatment safety was satisfactory, although still hampered by thromboembolism, mechanical problems, and infections.

A nonrandomized open-label phase 2 trial of nonischemic heart preservation for human heart transplantation

Pre-clinical heart transplantation studies have shown that ex vivo non-ischemic heart preservation (NIHP) can be safely used for 24 h. Here we perform a prospective, open-label, non-randomized phase II study comparing NIHP to static cold preservation (SCS), the current standard for adult heart transplantation. All adult recipients on waiting lists for heart transplantation were included in the study, unless they met any exclusion criteria. The same standard acceptance criteria for donor hearts were used in both study arms. NIHP was scheduled in advance based on availability of device and trained team members. The primary endpoint was a composite of survival free of severe primary graft dysfunction, free of ECMO use within 7 days, and free of acute cellular rejection ≥2R within 180 days. Secondary endpoints were I/R-tissue injury, immediate graft function, and adverse events. Of the 31 eligible patients, six were assigned to NIHP and 25 to SCS. The median preservation time was 223 min (IQR, 202–263) for NIHP and 194 min (IQR, 164–223) for SCS. Over the first six months, all of the patients assigned to NIHP achieved event-free survival, compared with 18 of those assigned to SCS (Kaplan-Meier estimate of event free survival 72.0% [95% CI 50.0–86.0%]). CK-MB assessed 6 ± 2 h after ending perfusion was 76 (IQR, 50–101) ng/mL for NIHP compared with 138 (IQR, 72–198) ng/mL for SCS. Four deaths within six months after transplantation and three cardiac-related adverse events were reported in the SCS group compared with no deaths or cardiac-related adverse events in the NIHP group. This first-in-human study shows the feasibility and safety of NIHP for clinical use in heart transplantation. ClinicalTrial.gov, number NCT03150147

Ischemia and reperfusion damage contribute to early graft dysfunction and recipient’s death. Here the authors show the feasibility and safety of a non-ischemic heart preservation method for heart transplantation in a non-randomized trial.

Cost-utility of venoarterial extracorporeal membrane oxygenation in cardiogenic shock and cardiac arrest

BACKGROUND

The use of venoarterial extracorporeal membrane oxygenation in cardiogenic shock keeps increasing, but its cost-utility is unknown.

METHODS

We studied retrospectively the cost-utility of venoarterial extracorporeal membrane oxygenation in a five-year cohort of consequent patients treated due to refractory cardiogenic shock or cardiac arrest in a transplant centre in 2013-2017. In our centre, venoarterial extracorporeal membrane oxygenation is considered for all cardiogenic shock patients potentially eligible for heart transplantation, and for selected postcardiotomy patients. We assessed the costs of the index hospitalization and of the one-year hospital costs, and the patients' health-related quality of life (response rate 71.7%). Based on the data and the population-based life expectancies, we calculated the amount and the costs of quality-adjusted life years gained both without discount and with an annual discount of 3.5%.

RESULTS

The cohort included 102 patients (78 cardiogenic shock; 24 cardiac arrest) of whom 67 (65.7%) survived to discharge and 66 (64.7%) to one year. The effective costs per one hospital survivor were 242,303€. Median in-hospital costs of the index hospitalization per patient were 129,967€ (interquartile range 150,340€). Mean predicted number of quality-adjusted life years gained by the treatment was 20.9 (standard deviation 9.7) without discount, and the median cost per quality-adjusted life year was 7474€ (interquartile range 10,973€). With the annual discount of 3.5%, 13.0 (standard deviation 4.8) quality-adjusted life years were gained with the cost of 12,642€ per quality-adjusted life year (interquartile range 15,059€).

CONCLUSIONS

We found the use of venoarterial extracorporeal membrane oxygenation in refractory cardiogenic shock and cardiac arrest justified from the cost-utility point of view in a transplant centre setting.

Outcome after heart-lung or lung transplantation in patients with Eisenmenger syndrome

OBJECTIVE

The optimal timing for transplantation is unclear in patients with Eisenmenger syndrome (ES). We investigated post-transplantation survival and transplantation-specific morbidity after heart-lung transplantation (HLTx) or lung transplantation (LTx) in a cohort of Nordic patients with ES to aid decision-making for scheduling transplantation.

METHODS

We performed a retrospective, descriptive, population-based study of patients with ES who underwent transplantation from 1985 to 2012.

RESULTS

Among 714 patients with ES in the Nordic region, 63 (9%) underwent transplantation. The median age at transplantation was 31.9 (IQR 21.1-42.3) years. Within 30 days after transplantation, seven patients (11%) died. The median survival was 12.0 (95% CI 7.6 to 16.4) years and the overall 1-year, 5-year, 10-year and 15-year survival rates were 84.1%, 69.7%, 55.8% and 40.6%, respectively. For patients alive 1 year post-transplantation, the median conditional survival was 14.8 years (95% CI 8.0 to 21.8), with 5-year, 10-year and 15-year survival rates of 83.3%, 67.2% and 50.0%, respectively. There was no difference in median survival after HLTx (n=57) and LTx (n=6) (14.9 vs 10.6 years, p=0.718). Median cardiac allograft vasculopathy, bronchiolitis obliterans syndrome and dialysis/kidney transplantation-free survival rates were 11.2 (95% CI 7.8 to 14.6), 6.9 (95% CI 2.6 to 11.1) and 11.2 (95% CI 8.8 to 13.7) years, respectively. The leading causes of death after the perioperative period were infection (36.7%), bronchiolitis obliterans syndrome (23.3%) and heart failure (13.3%).

CONCLUSIONS

This study shows that satisfactory post-transplantation survival, comparable with contemporary HTx and LTx data, without severe comorbidities such as cardiac allograft vasculopathy, bronchiolitis obliterans syndrome and dialysis, is achievable in patients with ES, with a conditional survival of nearly 15 years.

Circulating delta-like Notch ligand 1 is correlated with cardiac allograft vasculopathy and suppressed in heart transplant recipients on everolimus-based immunosuppression

Cardiac allograft vasculopathy (CAV) causes heart failure after heart transplantation (HTx), but its pathogenesis is incompletely understood. Notch signaling, possibly modulated by everolimus (EVR), is essential for processes involved in CAV. We hypothesized that circulating Notch ligands would be dysregulated after HTx. We studied circulating delta-like Notch ligand 1 (DLL1) and periostin (POSTN) and CAV in de novo HTx recipients (n = 70) randomized to standard or EVR-based, calcineurin inhibitor-free immunosuppression and in maintenance HTx recipients (n = 41). Compared to healthy controls, plasma DLL1 and POSTN were elevated in de novo (P < .01; P < .001) and maintenance HTx recipients (P < .001; P < .01). Use of EVR was associated with a treatment effect for DLL1. For de novo HTx recipients, a change in DLL1 correlated with a change in CAV at 1 (P = .021) and 3 years (P = .005). In vitro, activation of T cells increased DLL1 secretion, attenuated by EVR. In vitro data suggest that also endothelial cells and vascular smooth muscle cells (VSMCs) could contribute to circulating DLL1. Immunostaining of myocardial specimens showed colocalization of DLL1 with T cells, endothelial cells, and VSMCs. Our findings suggest a role of DLL1 in CAV progression, and that the beneficial effect of EVR on CAV could reflect a suppressive effect on DLL1. Trial registration numbers-SCHEDULE trial: ClinicalTrials.gov NCT01266148; NOCTET trial: ClinicalTrials.gov NCT00377962.

Continuous-flow LVADs in the Nordic countries: complications and mortality and its predictors

OBJECTIVES

The purpose of this study was to assess complications and mortality and its predictors, with continuous-flow left ventricular assist devices (CF-LVADs) in the Nordic Countries.

DESIGN

This was a retrospective, international, multicenter cohort study.

RESULTS

Between 1993 and 2013, 442 surgically implanted long-term mechanical assist devices were used among 8 centers in the Nordic countries. Of those, 238 were CF-LVADs (HVAD or HeartMate II) implanted in patients >18 years with complete data. Postoperative complications and survival were compared and Cox proportion hazard regression analysis was used to identify predictors of mortality. The overall Kaplan-Meier survival rate was 75% at 1 year, 69% at 2 years and 63% at 3 years. A planned strategy of destination therapy had poorer survival compared to a strategy of bridge to transplantation or decision (2-year survival of 41% vs. 76%, p < .001). The most common complications were non-driveline infections (excluding sepsis) (44%), driveline infection (27%), need for continuous renal replacement therapy (25%) and right heart failure (24%). In a multivariate model age and left ventricular diastolic dimension was left as independent risk factors for mortality with a hazard ratio of 1.35 (95% confidence interval (CI) [1.01-1.80], p = .046) per 10 years and 0.88 (95% CI [0.72-0.99], p = .044) per 5 mm, respectively.

CONCLUSION

Outcome with CF LVAD in the Nordic countries was comparable to other cohorts. Higher age and destination therapy require particularly stringent selection.

Preoperative right heart hemodynamics predict postoperative acute kidney injury after heart transplantation

Purpose

Acute kidney injury (AKI) frequently occurs after heart transplantation (HTx), but its relation to preoperative right heart hemodynamic (RHH) parameters remains unknown. Therefore, we aimed to determine their predictive properties for postoperative AKI severity within 30 days after HTx.

Methods

From 1984 to 2016, all consecutive HTx recipients (n = 595) in our tertiary referral center were included and analyzed for the occurrence of postoperative AKI staged by the kidney disease improving global outcome criteria. The effects of preoperative RHH parameters on postoperative AKI were calculated using logistic regression, and predictive accuracy was assessed using integrated discrimination improvement (IDI), net reclassification improvement (NRI), and area under the receiver operating characteristic curves (AUC).

Results

Postoperative AKI occurred in 430 (72%) patients including 278 (47%) stage 1, 66 (11%) stage 2, and 86 (14%) stage 3 cases. Renal replacement therapy (RRT) was administered in 41 (7%) patients. Patients with higher AKI stages had also higher baseline right atrial pressure (RAP; median 7, 7, 8, and in RRT 11 mmHg, p trend = 0.021), RAP-to-pulmonary capillary wedge pressure ratio (median 0.37, 0.36, 0.40, 0.47, p trend = 0.009), and lower pulmonary artery pulsatility index (PAPi) values (median 2.83, 3.17, 2.54, 2.31, p trend = 0.012). Higher RAP and lower PAPi values independently predicted AKI severity [adjusted odds ratio (OR) per doubling of RAP 1.16 (1.02–1.32), p = 0.029; of PAPi 0.85 (0.75–0.96), p = 0.008]. Based on IDI, NRI, and delta AUC, inclusion of these parameters improved the models’ predictive accuracy.

Conclusions

Preoperative PAPi and RAP strongly predict the development of AKI early after HTx and can be used as early AKI predictors.

Electronic supplementary material

The online version of this article (10.1007/s00134-018-5159-z) contains supplementary material, which is available to authorized users.

Predictors of 1-year mortality in heart transplant recipients: a systematic review and meta-analysis

Objective

A systematic summary of the observational studies informing heart transplant guideline recommendations for selection of candidates and donors has thus far been unavailable. We performed a meta-analysis to better understand the impact of such known risk factors.

Methods

We systematically searched and meta-analysed the association between known pretransplant factor and 1-year mortality identified by multivariable regression models. Our review used the Grading of Recommendations, Assessment, Development and Evaluation for assessing the quality of assessment. We pooled risk estimates by using random effects models.

Results

Recipient variables including age (HR 1.16 per 10-year increase, 95% CI 1.10–1.22, high quality), congenital aetiology (HR 2.35, 95% CI 1.62 to 3.41, moderate quality), diabetes (HR 1.37, 95% CI 1.15 to 1.62, high quality), creatinine (HR 1.11 per 1 mg/dL increase, 95% CI 1.06 to 1.16, high quality), mechanical ventilation (HR 2.46, 95% CI 1.48 to 4.09, low quality) and short-term mechanical circulatory support (MCS) (HR 2.47, 95% CI 1.04 to 5.87, low quality) were significantly associated with 1-year mortality. Donor age (HR 1.20 per 10-year increase, 95% CI 1.14 to 1.26, high quality) and female donor to male recipient sex mismatch (HR 1.38, 95% CI 1.06 to 1.80, high quality) were significantly associated with 1-year mortality. None of the operative factors proved significant predictors.

Conclusion

High-quality and moderate-quality evidence demonstrates that recipient age, congenital aetiology, creatinine, pulsatile MCS, donor age and female donor to male recipient sex mismatch are associated with 1-year mortality post heart transplant. The results of this study should inform future guideline and predictive model development.

Thirty years of heart transplantation at the University Medical Centre Utrecht

Purpose

To analyse patient demographics, indications, survival and donor characteristics for heart transplantation (HTx) during the past 30 years at the University Medical Centre Utrecht (UMCU).

Methods

Data have been prospectively collected for all patients who underwent HTx at the UMCU from 1985 until 2015. Patients who were included underwent orthotopic HTx at an age >14 years.

Results

In total, 489 hearts have been transplanted since 1985; 120 patients (25%) had left ventricular assist device (LVAD) implantation prior to HTx. A shift from ischaemic heart disease to dilated cardiomyopathy has been seen as the leading indication for HTx since the year 2000. Median age at HTx was 49 years (range 16–68). Median waiting time and donor age have also increased from 40 to 513 days and from 27 to 44 years respectively (range 11–65). Donor cause of death is now primarily stroke, in contrast to head and brain injury in earlier years. Estimated median survival is 15.4 years (95% confidence interval 14.2–16.6) There is better survival throughout these years.

Conclusion

Over the past 30 years, patient and donor demographics and underlying diseases have shifted substantially. Furthermore, the increase in waiting time due to lack of available donor hearts has led to a rise in the use of LVADs as bridge to transplant. Importantly, an improvement in survival rates is found over time which could be explained by better immunosuppressive therapy and improvements in follow-up care.

Karl Viktor Hall: From In Situ Vein Bypass to the Tilting Disc Heart Valve Prosthesis

In 1977, Karl Viktor Hall implanted a novel tilting disc heart valve prosthesis at Rikshospitalet in Oslo, Norway. The Medtronic-Hall valve was known for its excellent durability and low thrombogenicity. Hall popularized the use of the great saphenous vein in situ as an arterial shunt in the 1960s, made a metal stripper to lyse vein valves, and introduced electromagnetic flowmeters in vascular surgery. He performed the first coronary artery bypass graft in Scandinavia in 1969. Under his leadership the first heart transplantation and the first heart-lung transplantation were performed in Scandinavia by his successor Tor Frøysaker in 1983 and 1986, respectively.

Improved long-term survival in Dutch heart transplant patients despite increasing donor age: the Rotterdam experience

Over the past decades donor and recipient characteristics and medical management of heart transplantation (HT) patients have changed markedly. We studied the impact of these changes on long-term clinical outcome. Data of all consecutive HT recipients in our center have been collected prospectively. Cohort A (n = 353) was defined as the adult pts transplanted between 1984 and 1999 and was compared with cohort B (n = 227) transplanted between 2000 and 2013. Compared with cohort A, recipients in cohort B had older donors (mean age 29 vs. 43 years, donors aged >50 year: 2% vs. 33%, respectively). Survival at 1 and 10 years in cohort A vs. B was 89% vs. 86% and 53% vs. 68%, respectively (P = 0.02). Cohort B pts were treated more often with tacrolimus-based immunosuppression (77% vs. 22%; P = <0.0001) and early statins post-HT (88% vs. 18%; P = 0.0001), while renal function was better conserved at 5 and 10 years (P = 0.001 and 0.02). Multivariate analysis showed significant reduction in 10-year mortality with tacrolimus-based immunosuppression (HR 0.27 and 95% CI 0.17-0.42), hypertension post-HT (HR 0.5, 95% CI 0.36-0.72), and revascularization (HR 0.28, 95% CI 0.15-0.52). In spite of the use of much older donors, the long-term outcome after HT has improved considerably in the last decade, probably due to the introduction of newer treatment modalities.

Measured and not estimated glomerular filtration rate should be used to assess renal function in heart transplant recipients

BACKGROUND

In organ transplanted patients, impaired renal function is of major prognostic importance and influences therapeutic decisions. Therefore, monitoring of renal function with glomerular filtration rate (GFR) is of importance, both before and after heart transplantation (HTx). The GFR can be measured directly (mGFR) or estimated (eGFR) with equations based on circulating creatinine or cystatin C levels. However, these equations have not been thoroughly validated in the HTx population.

METHODS

We investigated the correlation, agreement and accuracy between mGFR (using (51)Cr-ethylenediaminetetraacetic acid or iohexol clearance) and three commonly used eGFR equations (Modification of Diet in Renal Disease, Cockcroft-Gault and Chronic Kidney Disease Epidemiology Collaboration) in a retrospective analysis of 416 HTx recipients followed between 1988 and 2012. Comparisons were performed prior to transplantation and at 1, 5 and 10 years of follow-up.

RESULTS

The correlations between eGFR and mGFR were only moderate, with r-values ranging from 0.55 preoperatively to 0.82 during follow-up. Most importantly, the level of agreement between eGFR and mGFR was very low for all three estimates, with percentage errors ranging from 93.3 to 157.3%. Also, the percentage of patients with eGFR within 30% of mGFR (P30) rarely reached the National Kidney Foundation recommended minimum level of 75%.

CONCLUSION

We argue that the accuracy and the precision of the most commonly used estimation equations for assessment of kidney function are unacceptably low and we believe that mGFR should be used liberally as the basis for clinical decision-making both before and after HTx when eGFR is subnormal.

The International Heart Transplant Survival Algorithm (IHTSA): a new model to improve organ sharing and survival

Background

Heart transplantation is life saving for patients with end-stage heart disease. However, a number of factors influence how well recipients and donor organs tolerate this procedure. The main objective of this study was to develop and validate a flexible risk model for prediction of survival after heart transplantation using the largest transplant registry in the world.

Methods and Findings

We developed a flexible, non-linear artificial neural networks model (IHTSA) and classification and regression tree to comprehensively evaluate the impact of recipient-donor variables on survival over time. We analyzed 56,625 heart-transplanted adult patients, corresponding to 294,719 patient-years. We compared the discrimination power with three existing scoring models, donor risk index (DRI), risk-stratification score (RSS) and index for mortality prediction after cardiac transplantation (IMPACT). The accuracy of the model was excellent (C-index 0.600 [95% CI: 0.595–0.604]) with predicted versus actual 1-year, 5-year and 10-year survival rates of 83.7% versus 82.6%, 71.4% – 70.8%, and 54.8% – 54.3% in the derivation cohort; 83.7% versus 82.8%, 71.5% – 71.1%, and 54.9% – 53.8% in the internal validation cohort; and 84.5% versus 84.4%, 72.9% – 75.6%, and 57.5% – 57.5% in the external validation cohort. The IHTSA model showed superior or similar discrimination in all of the cohorts. The receiver operating characteristic area under the curve to predict one-year mortality was for the IHTSA: 0.650 (95% CI: 0.640–0.655), DRI 0.56 (95% CI: 0.56–0.57), RSS 0.61 (95% CI: 0.60–0.61), and IMPACT 0.61 (0.61–0.62), respectively. The decision-tree showed that recipients matched to a donor younger than 38 years had additional expected median survival time of 2.8 years. Furthermore, the number of suitable donors could be increased by up to 22%.

Conclusions

We show that the IHTSA model can be used to predict both short-term and long-term mortality with high accuracy globally. The model also estimates the expected benefit to the individual patient.

Mid-term survival after continuous-flow left ventricular assist device versus heart transplantation

There is a paucity of data about mid-term outcome of patients with advanced heart failure (HF) treated with left ventricular assist device (LVAD) in Europe, where donor shortage and their aging limit the availability and the probability of success of heart transplantation (HTx). The aim of this study is to compare Italian single-centre mid-term outcome in prospective patients treated with LVAD vs. HTx. We evaluated 213 consecutive patients with advanced HF who underwent continuous-flow LVAD implant or HTx from 1/2006 to 2/2012, with complete follow-up at 1 year (3/2013). We compared outcome in patients who received a LVAD (n = 49) with those who underwent HTx (n = 164) and in matched groups of 39 LVAD and 39 HTx patients. Patients that were treated with LVAD had a worse risk profile in comparison with HTx patients. Kaplan-Meier survival curves estimated a one-year survival of 75.5 % in LVAD vs. 82.3 % in HTx patients, a difference that was non-statistically significant [hazard ratio (HR) 1.46; 95 % confidence interval (CI) 0.74-2.86; p = 0.27 for LVAD vs. HTx]. After group matching 1-year survival was similar between LVAD (76.9 %) and HTx (79.5 %; HR 1.15; 95 % CI 0.44-2.98; p = 0.78). Concordant data was observed at 2-year follow-up. Patients treated with LVAD as bridge-to-transplant indication (n = 22) showed a non significant better outcome compared with HTx with a 95.5 and 90.9 % survival, at 1- and 2-year follow-up, respectively. Despite worse preoperative conditions, survival is not significantly lower after LVAD than after HTx at 2-year follow-up. Given the scarce number of donors for HTx, LVAD therapy represents a valid option, potentially affecting the current allocation strategy of heart donors also in Europe.

An alternative approach to decellularize whole porcine heart

Scaffold characteristics are decisive for repopulating the acellular tissue with cells. A method to produce such a scaffold from intact organ requires a customized decellularization protocol. Here, we have decellularized whole, intact porcine hearts by serial perfusion and agitation of hypotonic solution, an ionic detergent (4% sodium deoxycholate), and a nonionic detergent (1% Triton X-100). The resultant matrix was characterized for its degree of decellularization, morphological and functional integrity. The protocol used resulted in extensive decellularization of the cardiac tissue, but the cytoskeletal elements (contractile apparatus) of cardiomyocytes remained largely unaffected by the procedure although their membranous organelles were completely absent. Further, several residual angiogenic growth factors were found to be present in the decellularized tissue.

Everolimus initiation and early calcineurin inhibitor withdrawal in heart transplant recipients: a randomized trial

In a randomized, open-label trial, everolimus was compared to cyclosporine in 115 de novo heart transplant recipients. Patients were assigned within 5 days posttransplant to low-exposure everolimus (3–6 ng/mL) with reduced-exposure cyclosporine (n = 56), or standard-exposure cyclosporine (n = 59), with both mycophenolate mofetil and corticosteroids. In the everolimus group, cyclosporine was withdrawn after 7–11 weeks and everolimus exposure increased (6–10 ng/mL). The primary efficacy end point, measured GFR at 12 months posttransplant, was significantly higher with everolimus versus cyclosporine (mean ± SD: 79.8 ± 17.7 mL/min/1.73 m2 vs. 61.5 ± 19.6 mL/min/1.73 m2; p < 0.001). Coronary intravascular ultrasound showed that the mean increase in maximal intimal thickness was smaller (0.03 mm [95% CI 0.01, 0.05 mm] vs. 0.08 mm [95% CI 0.05, 0.12 mm], p = 0.03), and the incidence of cardiac allograft vasculopathy (CAV) was lower (50.0% vs. 64.6%, p = 0.003), with everolimus versus cyclosporine at month 12. Biopsy-proven acute rejection after weeks 7–11 was more frequent with everolimus (p = 0.03). Left ventricular function was not inferior with everolimus versus cyclosporine. Cytomegalovirus infection was less common with everolimus (5.4% vs. 30.5%, p < 0.001); the incidence of bacterial infection was similar. In conclusion, everolimus-based immunosuppression with early elimination of cyclosporine markedly improved renal function after heart transplantation. Since postoperative safety was not jeopardized and development of CAV was attenuated, this strategy may benefit long-term outcome.

Heart failure highlights in 2012-2013

Heart failure has become the cardiovascular epidemic of the century. The European Journal of Heart Failure is dedicated to the advancement of knowledge in the field of heart failure management. In 2012 and 2013, several pioneering scientific discoveries and paradigm-shifting clinical trials have been published. In the current paper, we will discuss the most significant novel insights into the pathophysiology, diagnosis, and treatment of heart failure that were published during this period. All relevant research areas are discussed, including pathophysiology, co-morbidities, arrhythmias, biomarkers, clinical trials, and device therapy, including left ventricular assist devices.

Early postoperative complications after heart transplantation in adult recipients: asan medical center experience

BACKGROUND

Heart transplantation has become a widely accepted surgical option for end-stage heart failure in Korea since its first success in 1992. We reviewed early postoperative complications and mortality in 239 patients who underwent heart transplantation using bicaval technique in Asan Medical Center.

METHODS

Between January 1999 and December 2011, a total of 247 patients aged over 17 received heart transplantation using bicaval technique in Asan Medical Center. After excluding four patients with concomitant kidney transplantation and four with heart-lung transplantation, 239 patients were enrolled in this study. We evaluated their early postoperative complications and mortality. Postoperative complications included primary graft failure, cerebrovascular accident, mediastinal bleeding, renal failure, low cardiac output syndrome requiring intra-aortic balloon pump or extracorporeal membrane oxygenation insertion, pericardial effusion, and inguinal lymphocele. Follow-up was 100% complete with a mean follow-up duration of 58.4±43.6 months.

RESULTS

Early death occurred in three patients (1.3%). The most common complications were pericardial effusion (61.5%) followed by arrhythmia (41.8%) and mediastinal bleeding (8.4%). Among the patients complicated with pericardial effusion, only 13 (5.4%) required window operation. The incidence of other significant complications was less than 5%: stroke (1.3%), low cardiac output syndrome (2.5%), renal failure requiring renal replacement (3.8%), sternal wound infection (2.0%), and inguinal lymphocele (4.6%). Most of complications did not result in the extended length of hospital stay except mediastinal bleeding (p=0.034).

CONCLUSION

Heart transplantation is a widely accepted option of surgical treatment for end-stage heart failure with good early outcomes and relatively low catastrophic complications.