Cardiac transplantation

Dental care for cardiac transplant patients in the UK

Cardiac transplantation replaces a severely damaged non-functioning heart with a healthy heart from a donor. Within the UK, the number of cardiac transplants being performed each year is increasing, with significant improvements in longer-term survival. Dental professionals are therefore more likely to see and manage these patients in the pre- and post-transplant periods. This paper proposes a protocol for the dental management of these patients, reinforced by a case series from Scotland and London.

Comparative Analysis of Clinical Outcomes for COVID-19 and Influenza among Cardiac Transplant Recipients in the United States

COVID-19 infections can lead to worse outcomes in an immunocompromised population with multiple comorbidities, e.g., heart transplant patients. We used the National Inpatient Sample database to compare heart transplant outcomes in patients with COVID-19 vs. influenza. A total of 2460 patients were included in this study: heart transplant with COVID-19 (n = 1155, 47.0%) and heart transplant with influenza (n = 1305, 53.0%) with the primary outcome of in-hospital mortality. In-hospital mortality (n = 120) was significantly higher for heart transplant patients infected with COVID-19 compared to those infected with influenza (9.5% vs. 0.8%, adjusted OR: 51.6 [95% CI 4.3-615.9], p = 0.002) along with significantly higher rates of mechanical ventilation, acute heart failure, ventricular arrhythmias, and higher mean total hospitalization cost compared to the influenza group. More studies are needed on the role of vaccination and treatment to improve outcomes in this vulnerable population.

Spinal anaesthesia with intravenous sedation for total hip arthroplasty in two patients with a history of orthotopic heart transplantation

Many patients with orthotopic heart transplantation later undergo non-cardiac surgery. Historically, neuraxial anaesthesia has been avoided in these patients because the denervated heart is unable to compensate for hypotension via the baroreceptor reflex. Here, we present the cases of two patients with prior heart transplantation who underwent total hip arthroplasty under spinal anaesthesia with intravenous sedation. In both cases, this technique was well-tolerated haemodynamically. We propose that spinal anaesthesia with intravenous sedation can be a safe and efficacious anaesthetic technique for selected patients with a history of orthotopic heart transplantation, with careful intraoperative fluid and pharmacological management.

FRESH 3D bioprinting a contractile heart tube using human stem cell-derived cardiomyocytes

Here we developed a simplified model of the human heart, similar that observed in embryonic development where the heart first starts as a contractile linear tube. To this end, we created a bioinspired model of the human heart tube scaled ~10x larger, consisting of a collagen tube fabricated with high fidelity using freeform reversible of embedding of suspended hydrogels (FRESH) 3D bioprinting. The collagen tubes were cellularized using human stem cell-derived cardiomyocytes and cardiac fibroblasts via a rapid casting approach, with synchronous contractions ~3-4 days after fabrication and maintained for up to one month. Immunofluorescent staining confirmed dense, interconnected networks of sarcomeric α-actinin-positive cardiomyocytes. Electrophysiology was assessed using calcium imaging and demonstrated anisotropic calcium wave propagation along the heart tube with a conduction velocity of ~5 cm/s. Contractility and basic pump function were demonstrated by tracking the movement of fluorescent beads within the lumen to estimate fluid displacement and bead velocity. Results show the ability to displace fluid, but the simple linear design and lack of valves limited mean bead displacement. In summary, we have 3D bioprinted a contractile human heart tube as an initial step toward organ engineering by mimicking the simplified structure observed at early developmental time points.

Neurologic Complications in Heart Transplant Recipients Readmitted to the Intensive Care Unit

Introduction Neurologic complications after transplantation surgery are major causes of morbidity, and the incidence of neurologic complications among heart transplant recipients varies from 7% to 81%. In our study, we aimed to determine the incidence, etiologies, and risk factors of neurologic complications among patients readmitted to the intensive care unit (ICU) after heart transplantation. Method In this retrospective cohort study, the medical records of all patients who underwent cardiac transplantation from February 2003 to July 2019 were reviewed, and those admitted to the ICU due to neurologic complications during the early and late postoperative period were evaluated. The patients were divided into two groups based on the development of neurologic complications to compare demographic and other characteristics. Results A total of 130 heart transplant recipients were analyzed. We excluded 33 patients from the study because they either had neurologic complications or died postoperatively without discharge from the intensive care unit. The mean age of the cohort was 35.4 ± 18.5 years, and 74 (76.3%) were male. Out of those 97 heart transplant recipients, 22 (22.7%) developed neurologic complications. Five patients (22.7% ) were admitted to the ICU in the first month, six patients (27.3%) were admitted to the ICU between one and six months, and 11 patients (50%) were admitted to the ICU six months after transplantation due to neurologic complications. The most common diagnosis was posterior reversible encephalopathy syndrome (PRES) (n = 6, 27.3%). The other diagnoses were calcineurin inhibitor toxicity (n = 5, 22.7%), intracranial hemorrhage (n = 3, 13.6%), seizures (n = 2, 9.2%), stroke (n = 2, 9.2%), femoral neuropathy (n = 1, 4.5%), myopathy (n = 1, 4.5%), phrenic nerve damage (n = 1, 4.5%), and cerebral abscess (n = 1, 4.5%). The rate of neurologic complications was higher in males when compared with females (p = 0.03). Both groups were similar in terms of the etiologies of cardiac failure, coexisting disease, and anticoagulant and immunosuppressive usage. The requirement for mechanical ventilation, renal replacement therapy, and the incidence of acute kidney injury were similar in both groups (p > 0.05). The incidence of sepsis was significantly higher in patients with neurologic complications (n = 8, 36.4%, versus n = 5, 6.7%; p < 0.001). The mean length of hospital stay was significantly higher in patients with neurologic complications (21.4 ± 15.8 versus 11.1 ± 13.3 days, p = 0.01). The risk of developing neurologic complications is 3.036 times higher in males, and this is statistically significant (odds ratio (OR), 3.036; 95% confidence interval (CI), 1.078-8.444; p = 0.036). Conclusion Our results suggest that neurologic complications develop in 22.7% of heart transplant recipients admitted to the ICU, and half of them are seen after six months postoperatively. PRES was the most frequent (27.3%) neurologic complication. The risk of neurologic complications is three times higher for males. The mean length of hospital stay and incidence of sepsis were significantly higher in heart transplant recipients who developed neurologic complications.

A Risk Assessment Model for Stroke in the Early Post-Transplant Period in Adult Cardiac Allograft Recipients: A UNOS Database Analysis

BACKGROUND

Stroke risk in adult cardiac allograft recipients in the early postoperative period remains less defined. This study attempts to develop a risk assessment model in this population.

METHODS

Patients (≥18 years of age) between 2005 and 2015 who underwent cardiac transplantation were selected from the United Network for Organ Sharing database. The final study cohort had 20,915 patients. Risk factors were identified and multivariate logistic regression was used to test associations. SAS software was used for analyses.

RESULTS

Male recipients had a lower risk (odds ratio [OR] 0.7 [0.6-0.92]; P < .05) for stroke. Prolonged ischemic time (OR 1.2 [1.1-1.3), mechanical ventilation (OR 1.6 [1.2-1.9]), left ventricular assist device support (OR 1.8 [1.4-2.3]), black or Hispanic ethnicity (OR 1.33 [1.04-1.7]), days in status 1A (OR 1.05 [1.01-1.1]), recipient creatinine (OR 1.2 [1.02-1.4]), and type 2 diabetes (OR 1.4 [1.1-1.7]) were significant risk factors. A risk score was generated. Patients with a score of 8 had a 5-fold increase in event rate as compared with those with a score of 0. The c-statistic for this model was 0.65.

CONCLUSIONS

For the first time, a weighted risk score GIMVECH (female gender, ischemic time, mechanical ventilation, left ventricular assist device support, ethnicity, clinical history) was generated to assess stroke in the early post-transplant period.

Cost-impact analysis of baroreflex activation therapy in chronic heart failure patients in the United States

Background

The study evaluated the cost of baroreflex activation therapy plus guideline directed therapy (BAT + GDT) compared to GDT alone for HF patients with reduced ejection fraction and New York Heart Association Class III or II (with a recent history of III). Baroreflex activation therapy (BAT) is delivered by an implantable device that stimulates the baroreceptors through an electrode attached to the outside of the carotid artery, which rebalances the autonomic nervous system to regain cardiovascular (CV) homeostasis. The BeAT-HF trial evaluated the safety and effectiveness of BAT.

Methods

A cost impact model was developed from a U.S. health care payer or integrated delivery network perspective over a 3-year period for BAT + GDT versus GDT alone. Expected costs were calculated by utilizing 6-month data from the BeAT-HF trial and existing literature. HF hospitalization rates were extrapolated based on improvement in NT-proBNP.

Results

At baseline the expected cost of BAT + GDT were $29,526 per patient more than GDT alone due to BAT device and implantation costs. After 3 years, the predicted cost per patient was $9521 less expensive for BAT + GDT versus GDT alone due to lower rates of significant HF hospitalizations, CV non-HF hospitalizations, and resource intensive late-stage procedures (LVADs and heart transplants) among the BAT + GDT group.

Conclusions

BAT + GDT treatment becomes less costly than GDT alone beginning between years 1 and 2 and becomes less costly cumulatively between years 2 and 3, potentially providing significant savings over time. As additional BeAT-HF trial data become available, the model can be updated to show longer term effects.

Efficacy of Pharmacologic and Cardiac Implantable Electronic Device Therapies in Patients With Heart Failure and Reduced Ejection Fraction: A Systematic Review and Network Meta-Analysis

Background The treatment of heart failure with reduced ejection fraction has been the subject of numerous randomized controlled trials involving medications and cardiac implantable electronic device therapies. As newer effective pharmacological therapies suggest significant reductions in all-cause mortality, the role of additional device therapy in heart failure with reduced ejection fraction deserves further scrutiny. Methods A systematic review and network meta-analysis on the effect of medication and device therapies in heart failure with reduced ejection fraction on all-cause mortality was performed. Randomized controlled trials published between January 1980 and July 2017 were identified using Medline, EMBASE, and Cochrane Controlled Register of Trials databases. Pcnetmeta package in R was used to calculate treatment arm-based estimated rates, rate ratios, and probability ranks with 95% credible intervals. Results Combination therapy of ACE (angiotensin-converting enzyme) inhibitors or ARBs (angiotensin receptor blockers) with β-blockers (BBs) alone or in addition to implantable cardiac defibrillators or cardiac resynchronization therapy with defibrillators demonstrated a significant reduction of all-cause mortality when compared with placebo. By probability rank, implantable cardiac defibrillator+ACE inhibitor or ARB+BB+mineralocorticoid receptor antagonist, implantable cardiac defibrillator+ACE inhibitor or ARB+BB, and angiotensin receptor-neprilysin inhibitor+BB+mineralocorticoid receptor antagonist combination therapies have the highest probability of being ranked the best treatment. There was no significant difference in the rate of mortality when comparing angiotensin receptor-neprilysin inhibitor+BB+mineralocorticoid receptor antagonist to implantable cardiac defibrillator+optimal pharmacological combination therapy. Conclusions BB and renin-angiotensin system blockers alone or in combination with defibrillator device therapy have robust evidence for a reduction in mortality compared with placebo. The comparative efficacy of pharmacological therapy with angiotensin receptor-neprilysin inhibitors and device therapy deserves further investigation.

Anesthetic management of the patient undergoing heart transplantation

Cardiac transplantation is the treatment of choice for patients with end-stage heart failure. Over the years, significant advances in patient selection, donor optimization and selection, and optimization of immunosuppression strategies have markedly improved outcomes. In this review, we highlight patient selection, donor management and procurement, heart transplantation procedure, and intraoperative and postoperative management of heart transplants.

Long-term prognosis and cost-effectiveness of left ventricular assist device as bridge to transplantation: A systematic review

BACKGROUND

This systematic review aimed to evaluate the clinical outcomes and cost-effectiveness of left ventricular assist devices (LVADs) used as bridge to transplantation (BTT), compared to orthotopic heart transplantation (OHT) without a bridge.

METHOD

Systematic searches were performed in electronic databases with available data extracted from text and digitized figures. Meta-analysis of short and long-term term post-transplantation outcomes was performed with summation of cost-effectiveness analyses.

RESULTS

Twenty studies reported clinical outcomes of 4575 patients (1083 LVAD BTT and 3492 OHT). Five studies reported cost-effectiveness data on 837 patients (339 VAD BTT and 498 OHT). There was no difference in long-term post-transplantation survival (HR 1.24, 95% CI 1.00-1.54), acute rejection (HR 1.10, 95% CI 0.93-1.30), or chronic rejection and cardiac allograft vasculopathy (HR 0.99, 95% CI 0.73-1.36). No differences were found in 30-day post-operative mortality (OR 0.91, 95% CI 0.42-2.00), stroke (OR 1.64, 95% CI 0.43-6.27), renal failure (OR 1.43, 95% CI 0.58-3.54), bleeding (OR 1.56, 95% CI 0.78-3.13), or infection (OR 2.44, 95% CI 0.81-7.38). Three of the five studies demonstrated incremental cost-effectiveness ratios below the acceptable maximum threshold. The total cost of VAD BTT ranged from $316,078 to $1,025,500, and OHT ranged from $179,051 to $802,200.

CONCLUSION

LVADs used as BTT did not significantly alter post-transplantation long-term survival, rejection, and post-operative morbidity. LVAD BTT may be cost-effective, particularly in medium and high-risk patients with expected prolonged waiting times, renal dysfunction, and young patients.

Exo-organoplasty interventions: A brief review of past, present and future directions for advance heart failure management

Heart failure (HF) is a debilitating disease in which abnormal function of the heart leads to imbalance of blood demand to tissues and organs. The pathogenesis of HF is very complex and various factors can contribute including myocardial infarction, ischemia, hypertension and genetic cardiomyopathies. HF is the leading cause of death and its prevalence is expected to increase in parallel with the population age. Different kind of therapeutic approaches including lifestyle modification, medication and pacemakers are used for HF patients in NYHA I-III functional class. However, for advance stage HF patient's (NYHA IV), ventricle assist devices are clinically use and stem cells are under active investigation. Most of these therapies leads to modest symptoms relief and have no significant role in long-term survival rate. Currently there is no effective treatment for advance HF except heart transplantation, which is still remain clinically insignificant because of donor pool limitation. As HF is a result of multiple etiologies therefore multi-functional therapeutic platform is needed. Exo-organoplasty interventions are studied from almost one century. The major goals of these interventions are to treat various kind of heart disease from outside the heart muscle without having direct contact with blood. Various kind of interventions (devices and techniques) are developed in this arena with the passage of time. The purpose of this review is to describe the theory behind intervention devices, the devices themselves, their clinical results, advantages and limitations. Furthermore, to present a future multi-functional therapeutic platform (ASD) for advance stage HF management.

Ischemic Stroke after Heart Transplantation

Cerebrovascular complications after orthotopic heart transplantation (OHT) are more common in comparison with neurological sequelae subsequent to routine cardiac surgery. Ischemic stroke and transient ischemic attack (TIA) are more common (with an incidence of up to 13%) than intracranial hemorrhage (2.5%). Clinically, ischemic stroke is manifested by the appearance of focal neurologic deficits, although sometimes a stroke may be silent or manifests itself by the appearance of encephalopathy, reflecting a diffuse brain disorder. Ischemic stroke subtypes distribution in perioperative and postoperative period after OHT is very different from classical distribution, with different pathogenic mechanisms. Infact, ischemic stroke may be caused by less common and unusual mechanisms, linked to surgical procedures and to postoperative inflammation, peculiar to this group of patients. However, many strokes (40%) occur without a well-defined etiology (cryptogenic strokes). A silent atrial fibrillation (AF) may play a role in pathogenesis of these strokes and P wave dispersion may represent a predictor of AF. In OHT patients, P wave dispersion correlates with homocysteine plasma levels and hyperhomocysteinemia could play a role in the pathogenesis of these strokes with multiple mechanisms increasing the risk of AF. In conclusion, stroke after heart transplantation represents a complication with considerable impact not only on mortality but also on subsequent poor functional outcome.

Case report of a patient with left ventricular assistance device undergoing chemotherapy for a new diagnosis of lung cancer

The optimal management of cancer in patients with severe heart failure is not defined. This issue is particularly challenging when a diagnosis of limited-stage small cell lung cancer (SCLC) is made incidentally in the context of evaluating patient for candidacy for cardiac transplantation. Limited-stage SCLC is typically managed on a curative therapeutic paradigm with combined modality approach involving chemotherapy and radiation. Even with excellent performance status and good organ function, the presence of severe cardiomyopathy poses significant challenges to the delivery of even single modality approach with chemotherapy or radiotherapy, let alone the typical curative combined modality approach. With mechanical left ventricular devices to provide cardiac support, treatment options for cancer in the setting of advanced heart failure may be improved. Here we discuss the therapeutic dilemma involving a patient with severe cardiomyopathy and left ventricular assistant device (LVAD) who was found to have limited-stage SCLC during the evaluation process for cardiac transplantation.

Selective isolation of nanog-positive human amniotic mesenchymal cells and differentiation into cardiomyocytes

Adult cardiomyocytes have little ability to regenerate, thus cardiac regeneration therapy represents a potential method for treating severe heart failure. Human amniotic mesenchymal cells (hAMCs) have the potential to be a useful cell source for cardiac regeneration therapy. We attempted to isolate stem cells from hAMCs and differentiate them into cardiomyocytes. Nanog promoter-Cre plasmid and cytomegalovirus (CMV) promoter-loxP-STOP-loxP-Red-puro(r) plasmid were co-transfected into immortalized hAMCs (iHAMs). Nanog-positive iHAMs were treated with 5-azacytidine (5-aza), trichostatin A (TA), activin A (AA), and bone morphogenetic protein-4 (BMP-4), or co-cultured with murine fetal cardiomyocytes for cardiomyocytes differentiation. Isolated Nanog-positive iHAMs were analyzed by quantitative RT-PCR and immunofluorescent staining before and after differentiation. Expression of Nanog, Oct3/4, Sox2, and Klf4 was significantly higher in Nanog-positive than in Nanog-negative iHAMs. Nanog-positive iHAMs were stained for Nanog and Oct3/4 in the nucleus. Nanog-positive iHAMs treated with 5-aza expressed Nkx2.5, GATA-4, human atrial natriuretic peptide (hANP), cardiac troponin T (cTnT), myocin light chain (Mlc)-2a, Mlc-2v, β-myosin heavy chain (β-MHC), hyperpolarization-activated cyclic nucleotide gated channels (HCN)-4, and inwardly rectifying potassium channels (Kir)-2.1. Although Nanog-positive iHAMs treated with TA, AA, or BMP-4 expressed several cardiac markers, no contraction was observed. Co-cultured Nanog-positive iHAMs with murine fetal cardiomyocytes spontaneously contracted in a synchronized manner and expressed the cardiac markers. In conclusion, Nanog-positive hAMCs with characteristics of stem cells were isolated and differentiated into cardiomyocyte-like cells, suggesting that these isolated hAMCs could be a useful cell source for cardiac regeneration therapy.

Cardiovascular risk profile of patients with acute liver failure after liver transplantation when compared with the general population

BACKGROUND

As opposed to most solid-organ transplant recipients, patients with acute liver failure exhibit a pretransplant health status more comparable with the general population, and any posttransplant cardiovascular risk excess should thus be more attributable to transplantation-related factors alone.

METHODS

This study compared the cardiovascular risk of 77 consecutive patients with acute liver failure at 5 years after liver transplantation with that of the general population using age, sex, and residence area-standardized prevalence ratios (SPR).

RESULTS

At least one cardiovascular risk factor developed in 92% of patients. Treated hypertension, observed in 71% of patients at 5 years, was more common among patients than controls (SPR, 2.73; 95% confidence interval [CI], 2.06-3.55), whereas the 61% prevalence of dyslipidemia and 3% prevalence of impaired fasting glucose were significantly less frequent among patients (SPR, 0.69; 95% CI, 0.51-0.92 and SPR, 0.29; 95% CI, 0.04-1.00). The 5-year prevalence of diabetes (10%), overweight (32%), and obesity (13%) deviated nonsignificantly from controls (SPR 1.90, 0.85, and 0.58). Antibody therapy associated with a 1.49-fold increase in the risk of hypertension (95% CI, 1.15-1.94) and a 6.43-fold increase in the risk of diabetes (95% CI, 1.18-34.9). Immunosuppression-type, steroids, acute rejection, retransplantation, or graft steatosis revealed nonsignificant risk alterations.

CONCLUSIONS

Liver transplantation and associated immunosuppression evidently cause hypertension, and possibly elicit diabetes in susceptible individuals. Conversely, the often reported transplantation-associated increased burden of overweight/obesity and dyslipidemia might relate mostly to other factors.

Incidence and clinical predictors of primary opportunistic deep cutaneous mycoses in solid organ transplant recipients: a multicenter cohort study

BACKGROUND

Primary opportunistic deep cutaneous fungal infections may cause significant morbidity and mortality in solid organ transplant recipients (OTR), but no data exist about their incidence, timing, and clinical predictors in a long-term follow-up.

PATIENTS AND METHODS

A series of 3293 consecutive OTR including 1991 kidney, 929 heart, and 373 liver transplant recipients were enrolled. Patients were regularly followed up since time at transplantation (mean 5.5 yr +/-5.9 SD) and primary opportunistic fungal infections registered. Persons-year at risk (PYs), incidence rates (IR), incidence rate ratios (IRR), and 95% confidence intervals were computed.

RESULTS

Twenty-two cases of deep cutaneous mycoses were detected, (IR 1.2 cases per 1000 PYs) after a mean follow-up time since transplantation of 2.5 yr +/- 2.0 SD (median 1.8 yr). Six patients had subsequent systemic involvement and three patients died of systemic dissemination. A higher risk for mycoses was observed in the first two yr after transplantation, (IRR 35.9, p < 0.0001), in renal transplant recipients (IRR 5.1 p = 0.030), and in patients transplanted after the age of 50 (IRR 11.5 p = 0.020).

CONCLUSIONS

Primary deep cutaneous opportunistic mycoses in OTR occur mainly in the first two yr after transplantation, in renal transplant recipients, and in older patients.

Relationship between a validated molecular cardiac transplant rejection classifier and routine organ function parameters

BACKGROUND

As acute cellular cardiac allograft rejection is a systemic process affecting the entire organism, we hypothesized that scores of a peripheral blood mononuclear cell gene expression profiling (GEP) test developed and validated to rule out International Society of Heart and Lung Transplantation (ISHLT) grade > or = 3A/2R acute cellular cardiac allograft rejection also reflects biologically plausible changes of the routinely assessed clinical parameters.

METHODS

We retrospectively analyzed 76 patients who underwent GEP testing, at the time of their routine clinical follow-up in our Institution between February 1, 2006 and January 31, 2007. Data were analyzed with t-test, nonparametric tests, bivariate Spearman's correlation, and multivariate linear regression modeling.

RESULTS

More activated GEP-score correlated with longer corrected QT (QTc)-interval (r = 0.377, p = 0.001, n = 63), longer QRS duration (r = 0.231, p = 0.03, n = 66), higher heart rate (r = 0.221, p = 0.037, n = 66), higher serum creatinine (r = 0.26, p = 0.01, n = 75), higher gamma-glutamyl transferase (GGT) GGT (r = 0.266, p = 0.037, n = 46), lower pulmonary artery oxygen saturation (r = -0.313, p = 0.003, n = 76), lower platelet count (r = -0.372, p = 0.001, n = 74), lower monocyte count (r = -0.208, p = 0.040, n = 72), and lower high-density lipoprotein (HDL) HDL level (r = -0.242, p = 0.041, n = 53). Multivariate analysis showed a significant amount of variance in the GEP score independently explained by the variability of QTc-interval (beta = 1.998, p = 0.001) and platelet count (beta = -1.540, p = 0.017). Post hoc analysis of the 11 individual GEP-classifier genes showed WDRA40 (p = 0.02) and ras homolog gene family, member U (RHOU) RHOU (p = 0.01) independently related to mixed venous O(2)Sat%.

CONCLUSION

A GEP test developed and validated to detect the absence of cardiac rejection correlates with electrocardiographic and hemodynamic cardiac parameters as well as renal, hepatic, bone marrow, and lipid metabolism parameters suggesting a complex relationship between rejection, leukocytes, and organ function within the continuum between alloimmunological quiescence and rejection.

Pretransplant predictors of posttransplant adherence and clinical outcome: an evidence base for pretransplant psychosocial screening

INTRODUCTION

There is growing awareness, yet scant prospective evidence that pretransplant (TX) psychosocial factors may predict post-TX outcome. We examined which pre-TX psychosocial factors predict post-TX nonadherence with immunosuppression (NA) and clinical outcomes in heart, liver, and lung TX.

METHODOLOGY

We prospectively followed 141 patients (28 heart, 61 liver, and 52 lung) from pre-TX until 1 year post-TX. Multivariable analyses determined which pre-TX factors (i.e., anxiety, depression, personality traits, social support, adherence with medication, and smoking status) predict poor post-TX outcome (i.e., NA, late acute rejection, graft loss, and resource utilization), controlling for medical predictors of poor outcome.

RESULTS

Pre-TX self-reported medication nonadherence (odds ratio [OR]=7.9), lower received social support (OR=0.9), a higher education (OR=2.7), and lower "conscientiousness" (OR=0.8) were independent predictors of post-TX NA. Not living in a stable relationship predicted graft loss (OR=4.9). Pre-TX medication NA was the only predictor for presence of late acute rejection (OR=4.4). No other pre-TX predictors for poor outcome could be found.

CONCLUSION

This is the first prospective study demonstrating that selected pre-TX psychosocial factors predict post-TX NA and poor clinical outcome, implying that pre-TX screening should include this set of factors in addition to traditional medical criteria.

[Early complications and their treatment after heart transplantation in Hungary--experience of the first 16 years]

Heart transplantation is the most successful current long-term therapy of end stage cardiac failure.

AIM

In order to improve the results of the Hungarian heart transplantation activity, all data from the first 16 years were retrospectively examined and matched with the relevant literature.

METHODS

Between January 1992 and December 2007, 127 heart transplantations were performed in 125 patients in Hungary. Above the documentation of the Department of Cardiovascular Surgery, Semmelweis University, the archives of the Institute of Forensic Medicine, Semmelweis University, the Registry of Hungarian National Blood Transfusion Service, Organ Coordination Office and the data of the Gottsegen György National Institute of Cardiology were used.

RESULTS

Early mortality has been approaching the international level recently. Graft failure was the primary cause of death in the Hungarian practice as well, followed by infection, uncontrollable bleeding during surgery and multiorgan failure. In one case successful acute retransplantation was performed, but the most effective, ventricular assist device therapy is completely missing from the armamentarium. Excellent results were achieved with medical treatment against acute rejection such as written in the international literature.

CONCLUSIONS

For the sake of developing, regular usage of assist device therapy in Hungary is a prominent task. Development and application of standard protocols providing better quality in organ donor treatment and donation management have to be pressed.

Psychosocial and behavioural factors in heart transplant candidates – an overview

Mortality among heart transplant (HTX) candidates remains high. This review of the literature shows that psychosocial characteristics like depression, social isolation and coping strategies contribute to morbidity and mortality in heart failure (HF) patients, and may also be relevant to the prognosis of HTX candidates. Based on the research to date, physical activity favourably affects subjective and objective parameters not only in HF patients, but also in HTX candidates. Depression is prevalent among HTX candidates, especially in ischaemic patients, and seems to be related to earlier transplantation. Findings on the effects of depression on pretransplant mortality are conflicting. Not much is known concerning social isolation, coping, nutrition, or weight loss in this patient group. Identification of modifiable psychosocial and behavioural variables related to clinical status in this patient group is clearly needed and will aid the development of behavioural interventions to supplement medical therapies.

Oxidative stress implication in a new ex-vivo cardiac concordant xenotransplantation model

Xenotransplantation (XT) reveals a growing interest for the treatment of cardiomyopathy. The major barrier is an acute vascular rejection due to an acute humoral rejection. This pathogenesis is a difficult issue and in order to elaborate means for its prevention, we analysed the implication of oxidative stress (OS) on hearts from mini-pigs followed by reperfusion with either autologous or human blood in an attempt to simulate xenotransplantation. About 14 hearts were studied after a Langendorff blood reperfusion: allografts with autologous blood (n = 7) or xenografts with human blood (n = 7). Blood samples were drawn from the coronary sinus to assess ischemia and OS. In xenografts, arrhythmias occurred more frequently (p < 0.01, left ventricular systolic pressure decreased more significantly (p < 0.05), thiobarbituric acid-reactive substances concentrations increased at 30 min (0.7 +/- 0.1 vs. 2.4 +/- 0.3 mmol/l; p < 0.05) while vitamin A levels decreased (p < 0.05). XT was associated with a significant increase in ischemic injury and OS production. OS might play an eminent role in hyperacute humoral rejection.

Ex vivo hypothermic recirculatory adenoviral gene transfer to the transplanted pig heart

BACKGROUND

To facilitate the application of adenoviral gene therapy in clinical heart transplantation, we developed an ex vivo hypothermic recirculatory adenoviral gene transfer method to the transplanted pig heart.

METHODS

Experimental animals were assigned into three groups; controls, 1x10(8) plaque-forming units (pfu)/ml group and 1x10(9) pfu/ml group. During the 30 min gene transfer perfusion, 200 ml of University of Wisconsin solution containing the adenoviral vector was recirculated through the coronary vessels. The myocardial temperature was maintained below 4 degrees C and the perfusion pressure was adjusted at 50 mmHg.

RESULTS

Cardiac myocyte transduction efficiencies in the 1x10(8) pfu/ml group were 0.04% and 0.07%, whereas transduction efficiencies in the 1x10(9) pfu/ml group were widely distributed from 0.45% to 22.62%. The gene transduction efficiency increased with the virus titer. Additionally, no difference in the transduction efficiency was observed between different segments of the left ventricle. The current gene transfer method at 1x10(9) pfu/ml of adenovirus titer enabled homogeneous gene transduction into the transplanted pig heart up to a maximum of 22.62%.

CONCLUSIONS

This model can be applied to a large isolated heart and will greatly facilitate the investigation of gene therapy in large animal models of heart transplantation.

Waiting for a thoracic transplant in Eurotransplant*

The prospects of patients on the thoracic waiting list are governed by the chance of receiving an organ in time and by the outcome of the transplantation. The former probability is determined by a triad of disease severity, resource size and allocation rules. The aim of this study was to provide an objective description of the distributional effects of the thoracic allocation system in Eurotransplant. It appears that the interpretation of waiting-list outflow indicators is not straightforward and that it is difficult to assess the fairness of an organ allocation system in the framework of changing donor-organ availability. The timing of listing for heart transplantation can substantially be improved; whether this is also true for lung transplantation cannot be determined from the available data. Allocation schemes cannot solve the problem of organ shortage; a shift of attention toward collaboration with procurement professionals is needed.

Hepatocyte Growth Factor Delivered by Ultrasound-Mediated Destruction of Microbubbles Induces Proliferation of Cardiomyocytes and Amelioration of Left Ventricular Contractile Function in Doxorubicin-Induced Cardiomyopathy

At present, there is no curative strategy for advanced cardiomyopathy except for cardiac transplantation, which is not easily performed, mainly due to a shortage of donors. It has been reported that myocardial progenitor cells exist even in the postnatal heart, suggesting that myocardial progenitor cells could proliferate under some situations and might improve cardiac function in cardiomyopathy-induced hearts. In this study, recombinant human hepatocyte growth factor (rhHGF) was delivered using ultrasound-mediated destruction of microbubbles (UMDM) into the cardiomyopathy-induced heart by doxorubicin (20 mg/kg). Intravenous injection of rhHGF (IV-rhHGF) alone or UMDM alone failed to improve the morphology or the function of the cardiomyopathy-induced heart, but (IV-rhHGF + UMDM) treatment significantly improved the heart morphologically and functionally, and repetitive treatments of (IV-rhHGF + UMDM) enhanced the effects. The number of bromodeoxy-uridine-positive cardiomyocytes significantly increased in the (IV-rhHGF + UMDM)-treated hearts compared with the untreated hearts. Moreover, Sca-1+ myocardial progenitor cells express c-Met, a receptor for HGF. These results suggest that (IV-rhHGF + UMDM) treatment could morphologically and functionally improve the heart in the case of doxorubicin-induced cardiomyopathy through the proliferation of the myocardial progenitor cells.

Malignant melanoma in a candidate for heart transplantation

A superficial spreading melanoma (Breslow thickness 0.4 mm) was diagnosed in a 65-year-old candidate for heart transplantation due to refractory end stage heart failure. After extensive review of the literature (USA and Europe), no clear guidelines about the management of candidates for transplantation with a previous diagnosis of melanoma were found. As this patient had a 5-year probability of survival higher than 95% and heart transplantation was necessary for saving his life, the final decision was to perform the transplantation. Unfortunately, the patient died of heart failure before a suitable heart became available. This case stresses the need for early and continuous dermatological evaluation of all candidates for solid organ transplantation. Clear guidelines for screening of skin cancer before transplantation are needed.

Factors predicting 10-year survival after heart transplantation

BACKGROUND

We sought to identify factors predictive of long-term (>10-year) survival in heart transplant (HTx) recipients.

METHODS

Four hundred fifteen adult patients underwent HTx at our institution between August 1982 and May 1997. The 158 patients who survived >10 years (Group A) and the 116 patients who died between 2 and 6 years (Group B) of HTx were compared in terms of gender, gender mismatch, ethnicity, age, height, weight, United Network for Organ Sharing status, type of induction therapy (OKT3 or anti-thymocyte globulin), infections (bacterial, viral, fungal and protozoal), cytomegalovirus (CMV) status, CMV mismatch, diabetes mellitus, hypertension and incidence of rejection episodes and transplant coronary artery disease within 2 years of HTx.

RESULTS

Group A (135 men, 23 women; mean age 48 +/- 11 years) had significantly fewer post-HTx rejection episodes and viral, bacterial, fungal and total infections than did Group B (95 men, 21 women; mean age 49 +/- 12 years). Group A also had a significantly lower mean donor age, a lower incidence of pre-HTx diabetes, and a lower mean cholesterol level 1 year after HTx. In a multivariate analysis, fewer bacterial infections and rejection episodes after HTx, the absence of pre-HTx diabetes, and lower donor age were associated with longer survival.

CONCLUSIONS

Pre-HTx diabetes, donor age and incidences of infection and rejection within 2 years of HTx predict long-term (>10-year) survival. Better control of infection and rejection during the first 2 years after HTx may improve survival.

Cardiac transplantation

Cardiac transplantation is a proven, accepted mode of therapy for selected patients with end-stage heart failure, but the inadequate number of suitable donor hearts available ultimately limits its application. This chapter reviews adult cardiac transplantation, with an emphasis on the anesthetic considerations of the heart transplant operation itself.

Demonstrating time sequence and extent of sustained decrease in native heart ejection fraction after heterotopic transplantation

BACKGROUND

In this study we investigate the time sequence and extent of the sustained decrease in native heart ejection fraction (EF) after heterotopic heart transplantation (HHTx) when using gated cardiac blood pool scanning (GCBPS) and transthoracic echocardiography (TTE) One case report of 2 patients used post-operative GCBPS and TTE and found a significant deterioration in native heart EF post-operatively over the course of several years. Comparison with pre-operative measurements using these techniques in a series of patients has not been performed previously.

METHODS

Thirteen of 16 HHTx patients with adequate pre- and post-operative GCBPS follow-up were included in this study. All patients also underwent TTE post-operatively and the GCBPS results were correlated with the TTE findings.

RESULTS

GCBPS demonstrated a marked (21.1 +/- 4.7% vs 10.5 +/- 3.7%, p < 0.0001) decrease in native EF post-HHTx. Spontaneous echo contrast in the native left ventricle and/or poor opening of the mitral/aortic valves was noted at Day 1 in 4 of 5 patients who had a TTE at this stage. No further decline was noted between the first and last post-operative GCBPS (10.8 +/- 3% vs 8.6 +/- 2.1%, p = NS).

CONCLUSIONS

A dramatic decrease in native heart EF post-HHTx occurs as early as Day 1 post-transplant. Dissociation of ventricular contraction is the most likely cause. Studies have demonstrated that paced linkage (counterpulsation) between the ventricles results in improved hemodynamics. This may have clinical implications as to the timing of ejection of blood from a left ventricular assist device (LVAD) and for providing the best hemodynamics for the ventricle being assisted and for optimizing its chances of long-term recovery.

The role of bridge to transplantation: should LVAD patients be transplanted?

PURPOSE OF REVIEW

The decrease in useable donor organs means an increasing number of patients are requiring support with a left ventricular assist device (LVAD) for survival when their clinical status deteriorates before transplantation. We address whether these patients should be transplanted, if so, with what priority, and when and if they are not transplanted, what are the alternatives?

RECENT FINDINGS

The perioperative mortality and morbidity of LVAD insertion remains high. Infection and device failure still limit the safety of long periods of bridging and might necessitate earlier transplantation. Early results suggest that the smaller impeller pumps may be associated with a lower incidence of device failure and infection, but with more thromboembolic and hemorrhagic complications. Transplantation of LVAD patients results in survival rates as good as those with conventional transplantation, and the survival benefit is better than for non-LVAD-supported patients. A small number of LVAD patients have shown a significant improvement in myocardial function, sufficient enough to allow explantation of the device. The proportion of these patients has previously been reported to be as low as 5%, but a strategy to maximize recovery has allowed pump removal in approximately two thirds of dilated cardiomyopathy patients. In a recent destination therapy trial, survival in LVAD patients was superior to those on medical therapy, but the frequency of infection, bleeding, and malfunction of the device was higher.

SUMMARY

LVAD technology is continuing to evolve quickly, while transplantation is here to stay. The interaction between these two powerful modalities requires continued thoughtful evaluation for maximal benefit to patients.

Vasoactive peptides during long-term follow-up of patients after cardiac transplantation

BACKGROUND

Vasoactive peptides are accepted indicators of the degree of heart failure and its progression or improvement following medical therapy. Normalization of cardiac hemodynamics by cardiac transplantation (HTx) may lead to normalization of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) plasma levels shortly after the procedure.

METHODS

Long-term follow-up was done for 14 consecutive patients, 12 men and 2 women, 49 years of age (range 24 to 64 years). ANP and BNP were measured by radioimmunoassay (RIA) in central venous plasma samples (before breakfast, at steady state) at the following intervals after HTx: 7 to 30 (1), 31 to 60 (2), 61 to 90 (3), 120 to 180 (4) and 210 to 365 (5) days.

RESULTS

During follow-up, ANP decreased significantly within 2 months after HTx and continued of this level, whereas BNP decreased continuously without reaching normal values. The mean ratio of ANP:BNP increased from 3.23 to 8.01 during follow-up. Whereas right atrial pressure (RAP), right ventricular pressure (RVP), right ventricular end-diastolic pressure (RVEDP) and pulmonary capillary wedge pressure (PCWP) did not change during follow-up, cardiac output (CO) improved slightly, but significantly from 5.21 liters/min to 5.9 liters/min (p = 0.035).

CONCLUSIONS

Normalization of left ventricular function after orthotopic HTx does not induce an early diminution of ANP and BNP plasma levels to normal concentrations. Although elevated ANP concentrations showed only minimal changes within 1 year, BNP decreased significantly as early as 2 months after HTx, without reaching normal values during the year of follow-up. Also, the ratio of ANP and BNP increased significantly from 3.23 to 8.01. These results demonstrate the contribution of other factors beyond cardiac function that determine the levels of these peptides.

Orthotopic heart transplantation: highlights and limitations

A little more than three decades after the successful introduction of cardiac transplantation, this revolutionary concept of advanced heart failure treatment has gained tremendous momentum and is considered the gold standard therapy in selected patients. More specific modalities of immunosuppression continue to decrease the impact of acute and chronic rejection and immunosuppression-related side effects. The success of cardiac transplantation has led to a widespread initiation of transplant programs and a run on cardiac transplantation waiting lists. The increasing gap between waiting lists and donor organ supply has stimulated research to identify those patients who benefit most from cardiac transplantation, as well as research to develop alternative therapies for advanced heart failure. Furthermore, it serves as a stimulus to address paradigmatic issues that are fundamental to modern medicine and society.

Ventricular assist devices as destination therapy

The prospects for long-term mechanical circulatory support are improving. Axial flow pumps are a promising competitor to pulsatile first-generation LVADs, although the two may serve different patient populations. Centrifugal pumps are in the development phase and seem to require less anticoagulation. Clinical experience has established the safety of diminished pulse pressure circulation, and mechanical unloading appears to promote recovery of the native left ventricle. Under these circumstances, true left ventricular assist is preferable to ventricular replacement and detailed medical management improves patient outcomes. Further clinical trials of destination therapy are indicated and must use more reliable blood pumps implanted before terminal decline into multiorgan failure.

Reversible pulmonary hypertension in heart transplant candidates-pretransplant evaluation and outcome after orthotopic heart transplantation

BACKGROUND

Heart transplantation is the most effective treatment for well-selected patients with endstage heart failure. Unfortunately, transplant candidates with pulmonary hypertension (PHT) are often not considered for heart transplantation. This study was performed to assess the value of prostaglandin E(1) (PG-E(1)) for reduction of PHT and to predict the postoperative outcome, compared to patients without PHT.

PATIENTS AND METHODS

We studied a group of 151 consecutive heart transplant candidates using right heart catheterization. In patients with PHT (pulmonary vascular resistance, PVR> or =2.5 Wood-Units (WU) and/or transpulmonary gradient (TPG)> or =12 mmHg) a short-term treatment protocol with PG-E(1) was performed, to achieve PVR<2.5 WU and TPG<12 mmHg.

RESULTS

61 patients (40%) had PHT according to our criteria. Reduction of PHT was successful in 71% of patients (n=43), of these, 18 patients underwent cardiac transplantation and the 1-year mortality rate was 22% (n=4). The 1-year mortality rate in transplanted patients without PHT was 14% (n=3). There was no statistical difference in survival between the PHT and the non-PHT group. Outcome in patients without heart transplantation was similar in both groups, except for patients with non-reducible PHT (1-year mortality 50%).

CONCLUSIONS

Our study demonstrates the efficacy and safety of PG-E(1) in lowering PHT in heart transplant candidates, as well as the need for aggressive evaluation and treatment in these patients. Patients with reversible PHT have comparable post-transplant outcomes and no tendency to higher acute right ventricular failure.