Left ventricular dysfunction in potential heart donors and its influence on recipient outcomes

Heart transplant survival and the use of donors with intracranial bleeding: United Network for Organ Sharing Registry propensity-score matched analysis

Objective

The transplantation of hearts from donors who experienced intracranial bleeding (ICB) has been associated with inferior long-term survival in both single-center analyses and, more recently, with the United Network for Ogan Sharing Registry. The purpose of this study was to further explore this relationship through propensity score matching in recipients receiving donor hearts from ICB and non-ICB donors in a large national registry.

Methods

We performed a retrospective cohort analysis of the United Network for Organ Sharing Registry Organ Procurement and Transplantation Network between 2006 and 2018 for adult candidates wait-listed for isolated heart transplantation. Recipients were stratified into 2 groups: ICB and non-ICB donors. Propensity score matching was performed to estimate causal effects by using observational data. Kaplan-Meier analysis was used to estimate survival posttransplant. Cox proportional hazards modeling was used to evaluate the independent effect of ICB as a cause of death.

Results

A total of 25,315 candidates met inclusion criteria. ICB heart donors (n = 5529) were older (median age, 42 vs 27 years; P < .001), less likely men (54.5% vs 75.2%; P < .001), and more often had a history of smoking (20.1% vs 11.7%; P < .001), and hypertension (34.2% vs 9.5%; P < .001). Before matching there was a significant difference in long-term posttransplant survival; for example, the non-ICB (60.7% [interquartile range, 59.5%-61.9%] vs 56.8% (interquartile range, 54.7%-59.0%]; P < .0001). However, when analyzing the propensity-score matched groups for outcomes, no difference was found between the cohorts both in terms of long-term survival as well as in rates of rejection.

Conclusions

In the largest propensity score matching analysis of heart transplants from donors who had experienced ICB, we found similar survival and rejection rates in heart transplant recipients.

Echocardiographic surrogate of left ventricular stroke work in a model of brain stem death donors

BACKGROUND

The commonest echocardiographic measurement, left ventricular ejection fraction, can not necessarily predict mortality of recipients following heart transplantation potentially due to afterload dependency. Afterload-independent left ventricular stroke work index (LVSWI) is alternatively recommended by the current guideline; however, pulmonary artery catheters are rarely inserted in organ donors in most jurisdictions. We propose a novel non-invasive echocardiographic parameter, Pressure-Strain Product (PSP), as a potential surrogate of catheter-based LVSWI. This study aimed to investigate if PSP could correlate with catheter-based LVSWI in an ovine model of brain stem death (BSD) donors. The association between PSP and myocardial mitochondrial function in the post-transplant hearts was also evaluated.

METHODS

Thirty-one female sheep (weight 47 ± 5 kg) were divided into two groups; BSD (n = 15), and sham neurologic injury (n = 16). Echocardiographic parameters including global circumferential strain (GCS) and global radial strain (GRS) and pulmonary artery catheter-based LVSWI were simultaneously measured at 8-timepoints during 24-h observation. PSP was calculated as a product of GCS or GRS, and mean arterial pressure for PSPcirc or PSPrad, respectively. Myocardial mitochondrial function was evaluated following 6-h observation after heart transplantation.

RESULTS

In BSD donor hearts, PSPcirc (n = 96, rho = .547, p < .001) showed the best correlation with LVSWI among other echocardiographic parameters. PSPcirc returned AUC of .825 to distinguish higher values of cardiomyocyte mitochondrial function (cut-off point; mean value of complex 1,2 O2 Flux) in post-transplant hearts, which was greater than other echocardiographic parameters.

CONCLUSIONS

PSPcirc could be used as a surrogate of catheter-based LVSWI reflecting mitochondrial function.

Donor heart dysfunction and graft survival in liver and kidney transplants-A register-based study from Sweden

BACKGROUND AND AIM

Stress cardiomyopathy in donors can potentially affect graft function and longevity. This study aims to investigate the association between echocardiographic left ventricular ejection fraction (LVEF) < 50%, and/or the presence of left ventricular regional wall motion abnormalities (RWMA) in organ donors, and short- and long-term liver and kidney graft survival. Our secondary aim was to link graft survival with donor and recipient characteristics.

METHODS

All donors considered for liver and kidney donation with echocardiographic records at Sahlgrenska University Hospital between 2006 and 2016 were matched with their recipients through the Scandiatransplant register. The studied outcomes were graft survival, re-transplantation, and recipient death. Kaplan-Meier curves were used to plot time to event. Multivariate Cox-regression was used to test independence.

RESULTS

There were 370 liver donors and 312 kidney donors (matched with 458 recipients) with echocardiographic records at Sahlgrenska University Hospital between June 2006 and November 2016. Of patients with LV dysfunction by echocardiography, there were 102 liver- and 72 kidney donors. Univariate survival analyses showed no statistical difference in the short- and long-term graft survival from donors with LV dysfunction compared to donors without. Donor age > 65 years, recipient re-transplantation and recipient liver tumor were predictors of worse outcome in liver transplants (p < .05). Donor age > 65, donor hypertension, recipient re-transplantation, and a recipient diagnosis of diabetes or nephritis/glomerulonephritis had a negative association with graft survival in kidney transplants (p < .05).

CONCLUSION

We found no significant association between donor LV dysfunction and short- and long-term graft survival in liver and kidney transplants, suggesting that livers and kidneys from such donors can be safely transplanted.

Relationship between donor ejection fraction, left ventricular wall thickness and mortality in heart transplants recipients

This study explored the impact of donor left ventricular ejection fraction (EF) and left ventricular wall thickness (LVWT) on mortality among heart transplant (HTx) recipients. Utilizing data from the United Network for Organ Sharing (UNOS) registry, adult HTx recipients between 2006-2022 were analyzed. Patients were categorized into four groups based on donor EF(>50 % or ≤50 %) and LVWT(<1.4 cm or ≥1.4 cm). 21,012 patients were included. There were significant differences in baseline characteristics among the groups. Unadjusted mortality was 6.3 %, 6.0 %, 6.0 %, and 2.4 %(p=0.86) at 30-days; 16.2 %, 13.5 %, 16.8 %, and 7.3 %(p=0.08) at 1-year; and 32.2 %, 29.2 %, 35.4 %, and 29.0 %(p=0.18) at 5-years, respectively. In addition, adjusted mortality did not differ across the groups. There were no significant differences in recipient mortality in groups based on donor EF and LVWT. Expanding the donor selection criteria would allow for increase in the donor pool and assist in decreasing the mortality, while on the waitlist for HTx.

Multimodality Imaging in Advanced Heart Failure for Diagnosis, Management and Follow-Up: A Comprehensive Review

Advanced heart failure (AHF) presents a complex landscape with challenges spanning diagnosis, management, and patient outcomes. In response, the integration of multimodality imaging techniques has emerged as a pivotal approach. This comprehensive review delves into the profound significance of these imaging strategies within AHF scenarios. Multimodality imaging, encompassing echocardiography, cardiac magnetic resonance imaging (CMR), nuclear imaging and cardiac computed tomography (CCT), stands as a cornerstone in the care of patients with both short- and long-term mechanical support devices. These techniques facilitate precise device selection, placement, and vigilant monitoring, ensuring patient safety and optimal device functionality. In the context of orthotopic cardiac transplant (OTC), the role of multimodality imaging remains indispensable. Echocardiography offers invaluable insights into allograft function and potential complications. Advanced methods, like speckle tracking echocardiography (STE), empower the detection of acute cell rejection. Nuclear imaging, CMR and CCT further enhance diagnostic precision, especially concerning allograft rejection and cardiac allograft vasculopathy. This comprehensive imaging approach goes beyond diagnosis, shaping treatment strategies and risk assessment. By harmonizing diverse imaging modalities, clinicians gain a panoramic understanding of each patient's unique condition, facilitating well-informed decisions. The aim is to highlight the novelty and unique aspects of recently published papers in the field. Thus, this review underscores the irreplaceable role of multimodality imaging in elevating patient outcomes, refining treatment precision, and propelling advancements in the evolving landscape of advanced heart failure management.

Left Ventricular Dysfunction Associated With Brain Death: Results From the Donor Heart Study

BACKGROUND

Left ventricular dysfunction in potential donors meeting brain death criteria often results in nonuse of donor hearts for transplantation, yet little is known about its incidence or pathophysiology. Resolving these unknowns was a primary aim of the DHS (Donor Heart Study), a multisite prospective cohort study.

METHODS

The DHS enrolled potential donors by neurologic determination of death (n=4333) at 8 organ procurement organizations across the United States between February 2015 and May 2020. Data included medications administered, serial diagnostic tests, and transthoracic echocardiograms (TTEs) performed: (1) within 48 hours after brain death was formally diagnosed; and (2) 24±6 hours later if left ventricular (LV) dysfunction was initially present. LV dysfunction was defined as an LV ejection fraction <50% and was considered reversible if LV ejection fraction was >50% on the second TTE. TTEs were also examined for presence of LV regional wall motion abnormalities and their reversibility. We assessed associations between LV dysfunction, donor heart acceptance for transplantation, and recipient 1-year survival.

RESULTS

An initial TTE was interpreted for 3794 of the 4333 potential donors by neurologic determination of death. A total of 493 (13%) of these TTEs showed LV dysfunction. Among those donors with an initial TTE, LV dysfunction was associated with younger age, underweight, and higher NT-proBNP (N-terminal pro-B-type natriuretic peptide) and troponin levels. A second TTE was performed within 24±6 hours for a subset of donors (n=224) with initial LV dysfunction; within this subset, 130 (58%) demonstrated reversibility. Sixty percent of donor hearts with normal LV function were accepted for transplant compared with 56% of hearts with reversible LV dysfunction and 24% of hearts with nonreversible LV dysfunction. Donor LV dysfunction, whether reversible or not, was not associated with recipient 1-year survival.

CONCLUSIONS

LV dysfunction associated with brain death occurs in many potential heart donors and is sometimes reversible. These findings can inform decisions made during donor evaluation and help guide donor heart acceptance for transplantation.

Impact of donor ventricular function on heart transplantation outcomes

BACKGROUND

Some heart transplant (HTx) centers have expanded their donor eligibility criteria in response to the organ shortage; one area of active interest involves utilizing hearts with ventricular dysfunction. Our study seeks to identify if a relationship exists between donor left ventricular ejection fraction (LVEF) and ischemic time or donor age on HTx outcomes.

METHODS

We performed a retrospective analysis on adult patients who had a HTx between 1996 and 2021 (n = 46,936). Donor LVEF (dLVEF) values were categorized into three groups: <50%, 50%-70%, and >70%. Ischemic time and donor age were stratified into four groups: ≤2.0, 2.1-3.0, 3.1-4.0, >4.0 h, and ≤30, 31-40, 41-50, >50 years, respectively. The outcome of interest was long-term survival.

RESULTS

Multivariable survival analysis found a slight increase in overall mortality risk for patients with donor ejection fractions <50% (HR = 1.16, p = .013). However, subsequent subgroup investigation discovered that this elevated hazard was only applicable when ischemic time was prolonged to >3.0 h (3.1-4.0 h: HR = 1.23, p = .024; > 4.0 h: HR = 1.52, p < .001). There was no significant difference in survival between dLVEF groups when ischemic time was limited to ≤3.0 h or when stratified by donor age.

CONCLUSION

HTx patients with a low donor ejection fraction have comparable survival to recipients with a normal dLVEF when ischemic time is limited to ≤3.0 h. Reduced dLVEF does not appear to be sensitive to advanced donor age. The clinical implications of our study may encourage the recruitment of more donor hearts for transplantation.

RWMAs in critically ill patients with non-obstructed coronary arteries

INTRODUCTION

Left ventricular (LV) dysfunction is estimated to occur in 10%-25% of the general intensive care unit (ICU) population and is frequently seen as regional wall motion abnormalities (RWMAs). Although RWMA is mostly attributed to myocardial ischemia or infarction, some studies have suggested that nonischemic RWMA might also be prevalent. We sought to establish that RWMA can be seen in critically ill patients with normal coronary arteries and to explore reasons for RWMA in this population.

METHODS

In this retrospective study, data from the hospital angiography register and the ICU register were collated between 2012 and 2019. Patients were identified who underwent angiography in conjunction with their ICU stay and had RWMA on echocardiography. Patients were divided into either those with non-obstructed or those with obstructed coronary arteries. Cardiac magnetic resonance imaging (cMRI) examinations were reviewed if they had been performed on patients with non-obstructed coronaries.

RESULTS

We identified 53 patients with RWMA and non-obstructed coronary arteries and 204 patients with RWMA and obstructed coronary arteries. Patients with non-obstructed coronary arteries were more often female, younger, and had fewer cardiovascular risk factors. They less commonly had ST elevation, but more frequently had T-wave inversion or serious arrhythmias. Troponin levels were higher in patients with obstructed coronary arteries, but NT-proBNP was similar between the groups. There were no differences in risk-adjusted 90-day mortality between patients with non-obstructed versus obstructed coronary arteries (OR 1.21, [95% CI 0.56-2.64], p = .628). In those with non-obstructed coronary arteries, follow-up echocardiography was available for 38 patients, of whom 30 showed normalization of cardiac function. Of the 14 patients with non-obstructed coronary arteries on whom cMRI was performed, 7 had a tentative diagnosis of Takotsubo syndrome or myocardial stunning; 4 had a myocardial infarction (preexisting in 3 cases); 1 patient had acute myocarditis; 1 patient had post-myocarditis; and 1 patient was diagnosed with dilated cardiomyopathy.

CONCLUSION

RWMA can be seen to occur in critically ill patients in the absence of coronary artery obstruction. Several conditions can cause regional hypokinesia, and cMRI is useful to evaluate the underlying etiology.

Hemodynamic management in brain dead donors

Donor management is the key in the complex donation process, since up to 20% of organs of brain death donors (DBD) are lost due to hemodynamic instability. This challenge is made more difficult due to the lack of strong recommendations on therapies for hemodynamic management in DBDs and more importantly to the epidemiologic changes in these donors who are becoming older and with more comorbidities (marginal donors). In the present manuscript we aimed at summarizing the available evidence on therapeutic strategies for hemodynamic management (focusing on vasoactive drugs) and monitoring (therapeutic goals). Evidence on management in elderly DBDs is also summarized. Donor management continues critical care but with different and specific therapeutic goals since the number of donor goals met is related to the number of organs retrieved and transplanted. Careful monitoring of selected parameters (possibly including serial echocardiography) is the clinical tool able to guarantee the achievement and maintaining of therapeutic goals. Despide worldwide differences, norepinephrine is the vasoactive of choice in most countries but, whenever higher doses (> 0.2 mcg/kg/min) are needed, a second vasoactive drug (vasopressin) is advisable. Hormonal therapy (desmopressin, corticosteroid and thyroid hormone) are suggested in all DBDs independently of hemodynamic instability. In the single patient, therapeutic regimen (imprimis vasoactive drugs) should be chosen also according to the potential organs retrievable (i.e. heart vs liver and kidneys).

Pathophysiology of Takotsubo syndrome - a joint scientific statement from the Heart Failure Association Takotsubo Syndrome Study Group and Myocardial Function Working Group of the European Society of Cardiology - Part 2: vascular pathophysiology, gender and sex hormones, genetics, chronic cardiovascular problems and clinical implications

While the first part of the scientific statement on the pathophysiology of Takotsubo syndrome was focused on catecholamines and the sympathetic nervous system, in the second part we focus on the vascular pathophysiology including coronary and systemic vascular responses, the role of the central and peripheral nervous systems during the acute phase and abnormalities in the subacute phase, the gender differences and integrated effects of sex hormones, genetics of Takotsubo syndrome including insights from microRNA studies and inducible pluripotent stem cell models of Takotsubo syndrome. We then discuss the chronic abnormalities of cardiovascular physiology in survivors, the limitations of current clinical and preclinical studies, the implications of the knowledge of pathophysiology for clinical management and future perspectives and directions of research.

Regional left ventricular systolic dysfunction associated with critical illness: incidence and effect on outcome

Aims

Left ventricular (LV) dysfunction can be triggered by non‐cardiac disease, such as sepsis, hypoxia, major haemorrhage, or severe stress (Takotsubo syndrome), but its clinical importance is not established. In this study, we evaluate the incidence and impact on mortality of LV dysfunction associated with critical illness.

Methods and results

In this single‐centre, observational study, consecutive patients underwent an echocardiographic examination within 24 h of intensive care unit (ICU) admission. LV systolic dysfunction was defined as an ejection fraction (EF) < 50% and/or regional wall motion abnormalities (RWMA). A cardiologist assessed patients with LV dysfunction for the presence of an acute or chronic cardiac disease, and coronary angiography was performed in high‐risk patients. Of the 411 patients included, 100 patients (24%) had LV dysfunction and in 52 (13%) of these patients, LV dysfunction was not attributed to a cardiac disease. Patients with LV dysfunction and non‐cardiac disease had higher mortality risk score (Simplified Acute Physiologic Score 3 score), heart rate, noradrenaline doses, and lactate levels as well as decreased EF, stroke volume, and cardiac output compared with patients with normal LV function. Diagnoses most commonly associated with LV dysfunction and non‐cardiac disease were sepsis, respiratory insufficiency, major haemorrhage, and neurological disorders. RWMA (n = 40) with or without low EF was more common than global hypokinesia (n = 12) and was reversible in the majority of cases. Twelve patients had a circumferential pattern of RWMA in concordance with Takotsubo syndrome. Crude 30 day mortality was higher in patients with LV dysfunction and non‐cardiac disease compared with patients with normal LV function (33% vs. 18%, P = 0.023), but not after risk adjustment (primary outcome) {odds ratio [OR] 1.56 [confidence interval (CI) 0.75–3.39], P = 0.225}. At 90 days, crude mortality was 44% and 22% (P = 0.002), respectively, in these groups. This difference was also significant after risk adjustment [OR 2.40 (CI 1.18–4.88), P = 0.016].

Conclusions

Left ventricular systolic dysfunction is commonly triggered by critical illness, is frequently seen as regional hypokinesia, and is linked to an increased risk of death. The prognostic importance of LV dysfunction in critical illness might be underestimated.

Impact of Reported Donor Ejection Fraction on Outcome after Heart Transplantation

OBJECTIVES

 The global shortage of donor organs has urged transplanting units to extend donor selection criteria, for example, impaired left ventricular function (LVF), leading to the use of marginal donor hearts. We retrospectively analyzed our patients after orthotopic heart transplantation (oHTX) with a focus on the clinical outcome depending on donor LVF.

METHODS

 Donor reports, intraoperative, echocardiographic, and clinical follow-up data of patients undergoing oHTX at a single-center between September 2010 and June 2020 were retrospectively analyzed. Recipients were divided into two groups based on donor left ventricular ejection fraction (dLVEF): impaired dLVEF (group I; dLVEF ≤ 50%; n = 23) and normal dLVEF group (group N; dLVEF > 50%; n = 137).

RESULTS

 There was no difference in 30-day, 90-day, and 1-year survival. However, the duration of in-hospital stay was statistically longer in group I than in group N (N: 40.9 ± 28.3 days vs. I: 55.9 ± 39.4 days, p < 0.05). Furthermore, postoperative infection events were significantly more frequent in group I (p = 0.03), which was also supported by multivariate analysis (p = 0.03; odds ratio: 2.96; confidence interval: 1.12-7.83). Upon correlation analysis, dLVEF and recipient LVEF prove as statistically independent (r = 0.12, p = 0.17).

CONCLUSIONS

 Impaired dLVEF is associated with prolonged posttransplant recovery and slightly increased morbidity but has no significant impact on survival up to 1 year posttransplant.

Severe Acute Respiratory Distress Syndrome in Potential Organ Donors-Rescue Prone Positioning: A Case Report

Organ transplantation is a recognized treatment for many critical organ insufficiencies. One of the main problems in transplantation is the mismatch between organ donation and demand. It is very important to improve donor eligibility after brain stem death and to minimize insult to donatable organs by appropriate donor management. We present prone positioning as an effective supportive method of organ optimization in patients with acute respiratory distress syndrome with severe hypoxemia and hemodynamic instability.

The Year in Cardiothoracic Transplantation Anesthesia: Selected Highlights from 2019

The highlights in cardiothoracic transplantation focus on the recent research pertaining to heart and lung transplantation, including expansion of the donor pool, the optimization of donors and recipients, the use of mechanical support, the perioperative and long-term outcomes in these patient populations, and the use of transthoracic echocardiography to diagnose rejection.