Neurologic complications following heart transplantation in the modern era: decreased incidence, but postoperative stroke remains prevalent

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.

Mechanical Circulatory Support Prior to Heart Transplantation Predicts Early Post-Operative Stroke

BACKGROUND

Mechanical circulatory support (MCS) devices are often deployed to treat patients with refractory cardiogenic shock, rapid deterioration of heart failure, and inotrope-dependent patients. Stroke is a common complication of MCS therapy. This study assesses the risk of stroke during the early post-heart transplantation (HT) period (days from successful HT to discharge or death) in patients who received MCS therapy leading to HT.

METHODS

Data were derived from the United Organ Sharing (UNOS) database. MCS modalities studied include left ventricular assist devices (LVAD), right ventricular assist devices (RVAD), biventricular ventricular assist devices (BiVAD), and extra-corporeal membrane oxygenation (ECMO). A multiple logistic regression model was used to determine the risk of stroke during the early post-HT period associated in patients treated with MCS leading to HT.

RESULTS

Between 1988 and 2014, 10,258 patients received MCS therapy leading to HT. Of these, 160 patients (1.96%) developed stroke during the early post-HT period. Multiple regression analysis showed that MCS modalities and associated odds ratios for early post-HT stroke and associated 95% confidence intervals were as follows: LVAD (1.44, 0.70-2.94), RVAD (2.89, 1.03-8.05, BiVAD (3.24, 1.15-9.10), ECMO (2.27 (1.17-4.40), and any MCS (1.60 (1.20-2.12).

CONCLUSIONS

With the exception of left ventricular assist devices, use of MCS modalities leading to HT is significantly and independently associated with stroke during the early post-HT period.

Imaging spectrum of central nervous system complications of hematopoietic stem cell and solid organ transplantation

Neurologic complications are common after hematopoietic stem cell transplantation (HSCT) and solid organ transplantation (SOT) and affect 30-60% of transplant recipients. The aim of this article is to provide a practical imaging approach based on the timeline and etiology of CNS abnormalities, and neurologic complications related to transplantation of specific organs. The lesions will be classified based upon the interval from HSCT procedure: pre-engraftment period <30 days, early post-engraftment period 30-100 days, late post-engraftment period >100 days, and the interval from SOT procedure: postoperative phase 1-4 weeks, early posttransplant syndromes 1-6 months, late posttransplant syndromes >6 months. Further differentiation will be based on etiology: infections, drug toxicity, metabolic derangements, cerebrovascular complications, and posttransplantation malignancies. In addition, differentiation will be based on complications specific to the type of transplantation: allogeneic and autologous hematopoietic stem cells (HSC), heart, lung, kidney, pancreas, and liver. Thus, in this article we emphasize the strategic role of neuroradiology in the diagnosis and response to treatment by utilizing a methodical approach in the work up of patients with neurologic complications after transplantation.

Clinical Characteristics of Transplant-associated Encephalopathy in Children

We aimed to analyze characteristics of encephalopathy after both hematopoietic stem cell and solid organ pediatric transplantation. We retrospectively reviewed medical records of 662 pediatric transplant recipients (201 with liver transplantation [LT], 55 with heart transplantation [HT], and 67 with kidney transplantation [KT], 339 with allogeneic hematopoietic stem cell transplantation [HSCT]) who received their graft organs at Asan Medical Center between January 2000 and July 2014. Of the 662 patients, 50 (7.6%) experienced encephalopathy after transplantation. The incidence of encephalopathy was significantly different according to the type of organ transplant: LT, 16/201 (8.0%), HT, 13/55 (23.6%), KT, 5/67 (7.5%), and HSCT, 16/339 (4.7%) (P < 0.001). Drug-induced encephalopathy (n = 14) was the most common encephalopathy for all transplant types, but particularly after HSCT. Hypertensive encephalopathy was the most common after KT and HT, whereas metabolic encephalopathy was the most common after LT. The median time to encephalopathy onset also differed according to the transplant type: 5 days after KT (range 0-491 days), 10 days after HT (1-296 days), 49.5 days after HSCT (9-1,405 days), and 39 days after LT (1-1,092 days) (P = 0.018). The mortality rate among patients with encephalopathy was 42.0% (n = 21/50). Only 5 patients died of neurologic complications. Transplant-associated encephalopathy presented different characteristics according to the type of transplant. Specialized diagnostic approach for neurologic complications specific to the type of transplant may improve survival and quality of life in children after transplantation.

Neurologic Complications After Cardiac Transplant

OBJECTIVES

Cardiac transplant is the best available therapy for patients with end-stage heart failure. Neurologic complications occur at a rate of 30% to 70% in patients undergoing cardiac transplant, and they affect mortality and morbidity of these patients. Risk factors for neurologic complications include immunosuppressive medication toxicity, infections, brain lesions, and metabolic disorders. The aim of our study was to determine the incidence of neurologic complications in adult patients undergoing cardiac transplant.

MATERIALS AND METHODS

We retrospectively evaluated the medical records of 70 patients who underwent cardiac transplant between 2004 and April 2016. We recorded the demographic data, neurologic symptoms, neurologic examination findings, laboratory test results, brain imaging study results, and treatments received of the patients.

RESULTS

Of the 70 patients enrolled, 55 were male and 15 were female patients. The age range was 18 to 63 years, and the mean age was 42.4 years. Twelve patients had encephalopathy, 4 had neuropathic pain, 3 had tremor, 2 had ischemic cerebrovascular accident, 7 had posterior reversible encephalopathy syndrome, and 1 had drop foot. Encephalopathy usually developed secondary to other neurologic disorders. The incidence of neurologic complications in adult patients undergoing cardiac transplant was 30%.

CONCLUSIONS

Neurologic complications are common after cardiac transplant. We observed an incidence of 30% for neurologic complications in our clinic, with encephalopathy being the most common complication. Encephalopathy most commonly developed secondary to posterior reversible encephalopathy syndrome.

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.

The neurology of solid organ transplantation

Transplantation is the rescue treatment for end-stage organ failure with more than 110,000 solid organs transplantations performed worldwide annually. Recent advances in transplantation procedures and posttransplantation management have improved long-term survival and quality of life of transplant recipients, shifting the focus from acute perioperative critical care needs toward long-term chronic medical problems. Neurologic complications affect up to 30-60 % of solid organ transplant recipients. Common etiologies include opportunistic infections and toxicities of antirejection medications, and wide spectrum of toxic and metabolic disturbances. Most complications are common to all allograft types, but some are relatively specific for individual allograft types (e.g., central pontine myelinolysis in liver transplant recipients). Close collaboration between neurologists and other transplant team members is essential for effective management. Early recognition of complications and accurate diagnosis leading to timely treatment is essential to reduce the morbidity and improve the overall transplant outcome.

Neurologic aspects of heart transplantation

Cardiac transplantation remains the best treatment option for patients with end-stage, NYHA class IV heart failure who have failed conventional therapy. However, transplant rates have remained static largely due to limited organ donor supplies. Therefore, appropriate allocation of this precious resource is critical to maximize benefit, both at a patient level and at a societal level. Neurologic diseases, such as cerebrovascular disease and peripheral neuropathy, are prevalent in this patient population, as the major risk factors for heart disease place patients at risk for neurologic disease as well. Examples include hypertension, smoking, hypercholesterolemia, obesity, and diabetes. Pretransplant neurologic evaluation is very important to identify conditions that may limit survival after cardiac transplantation. In general, systemic diseases exacerbated by immunosuppression, conditions limiting ability to rehabilitate, and dementias are considered contraindications. Post-transplant neurologic complications are divided into central versus peripheral, and early versus late. The most common early complication is ischemic stroke. Other serious complications include hemorrhagic stroke, encephalopathy, and critical illness neuropathy. Over the long term, post-transplant immunosuppressive regimens are considered "a double edged sword." Although immunosuppressive medications are critical to preventing rejection and allograft dysfunction, they do have significant risk of morbidity and mortality associated with them, including neurologic side-effects. These include: (1) drug toxicities, such as lowering of seizure thresholds; (2) encephalopathy, such as posterior reversible encephalopathy syndrome (PRES); (3) infections; (4) malignancies, such as post-transplant lymphoproliferative disorder (PTLD). Many of the same considerations discussed in adult heart transplant recipients apply to pediatric heart transplant recipients as well. In children, seizures are the most common neurologic complication, although other neurologic complication rates are comparable.

Analytic Review: Neurological Complications of Transplantation

Recipients of solid organ or hematopoietic cell transplants are at risk of life-threatening neurological disorders including encephalopathy, seizures, infections and tumors of the central nervous system, stroke, central pontine myelinolysis, and neuromuscular disorders—often requiring admission to, or occurring in, the intensive care unit (ICU). Many of these complications are linked directly or indirectly to immunosuppressive therapy. However, neurological disorders may also result from graft versus host disease, or be an expression of the underlying disease which prompted transplantation, as well as injury induced during radiation, chemotherapy, surgery, and ICU stay. In rare cases, neuroinfectious pathogens may be transmitted with the transplanted tissue or organ. Diagnosis may be a challenge because clinical symptoms and findings on neuroimaging lack specificity, and a biological specimen or tissue diagnosis is often needed for definitive diagnosis. Management is centered on preventing further neurological injury, etiology-targeted therapy, and balancing the benefits and toxicities of specific immunosuppressive agents.

Antithrombotic medication for cardioembolic stroke prevention

Embolism of cardiac origin accounts for about 20% of ischemic strokes. Nonvalvular atrial fibrillation is the most frequent cause of cardioembolic stroke. Approximately 1% of population is affected by atrial fibrillation, and its prevalence is growing with ageing in the modern world. Strokes due to cardioembolism are in general severe and prone to early recurrence and have a higher long-term risk of recurrence and mortality. Despite its enormous preventive potential, continuous oral anticoagulation is prescribed for less than half of patients with atrial fibrillation who have risk factors for cardioembolism and no contraindications for anticoagulation. Available evidence does not support routine immediate anticoagulation of acute cardioembolic stroke. Anticoagulation therapy's associated risk of hemorrhage and monitoring requirements have encouraged the investigation of alternative therapies for individuals with atrial fibrillation. New anticoagulants being tested for prevention of stroke are low-molecular-weight heparins (LMWH), unfractionated heparin, factor Xa inhibitors, or direct thrombin inhibitors like dabigatran etexilate and rivaroxaban. The later exhibit stable pharmacokinetics obviating the need for coagulation monitoring or dose titration, and they lack clinically significant food or drug interaction. Moreover, they offer another potential that includes fixed dosing, oral administration, and rapid onset of action. There are several concerns regarding potential harm, including an increased risk for hepatotoxicity, clinically significant bleeding, and acute coronary events. Therefore, additional trials and postmarketing surveillance will be needed.

Neurologic complications of cardiac surgery and interventional cardiac procedures

Neurologic complications of cardiac surgery and interventional cardiac procedures may affect the central nervous system or the peripheral nervous system. The most common central nervous system complications are strokes and seizures. This article provides a succinct neuroanatomic and pathophysiologic approach to a wide array of neurologic complications associated with cardiac procedures.

Cerebrovascular complications after heart transplantation

Neurological complications in orthotopic heart transplantation represent a major cause of morbidity and mortality despite successful transplantation. The most frequent perioperative neurological complications are delirium or encephalopathy. In this period cerebrovascular complication ranges between 5-11%. After the perioperative period, the 5-year stroke risk after cardiac transplantation is 4.1%. In a retrospective study conducted with 314 patients who underwent cardiac transplantation, it was found that 20% of cerebrovascular complications occurred within the first two weeks after transplantation, while 80% occurred in the late postoperative phase. Of these, ischemic stroke is the most common subtype. In the perioperative periode, hemodynamic instability, cardiac arrest, extracorporeal circulation over 2 hours, prior history of stroke, and carotid stenosis greater than 50% have been reported to be risk factors for the occurrence of cerebrovascular complications. Perioperative cerebrovascular complications are associated with higher mortality and poor functional outcome at one year follow-up.After the perioperative period, the only factor that has been significantly associated with an increased risk of cerebrovascular complications is a history of prior stroke, either ischemic or hemorrhagic. Other associated factors include unknown atrial fibrillation, septic emboli from endocarditis, cardiac catheterization and perioperative hemodynamic shock. According to the TOAST etiologic classification, the most prevalent etiologic subtype of ischemic stroke is undetermined cause.

Infectious and non-infectious neurologic complications in heart transplant recipients

Neurologic complications are important causes of morbidity and mortality in heart transplant (HT) recipients. New immunomodulating agents have improved survival rates, although some have been associated with a high rate of neurologic complications (infectious and non-infectious). We conducted this study to analyze the frequency of these complications, before and after the use of daclizumab induction therapy. We reviewed all neurologic complications in our HT cohort, comparing infectious with non-infectious complications over 2 periods of time in which different induction therapies were used (316 patients with OKT3 or antithymocyte globulin from 1988 to 2002, and 68 patients with daclizumab from 2003 to 2006). Neurologic complications were found in 75/384 patients (19.5%) with a total of 78 episodes. Non-infectious complications accounted for 68% of the 78 episodes of neurologic complications. A total of 51 patients and 53 episodes were detailed as follows: 25 episodes of stroke (25 of 78 total episodes, 32%; 19 ischemic, 6 hemorrhagic); 7 neuropathies; 6 seizures; 4 episodes of transient ischemic attack (TIA); 3 anoxic encephalopathy; 2 each brachial plexus palsy and metabolic encephalopathy; and 1 each myoclonia, central nervous system (CNS) lymphoma, subdural hematoma, and Cotard syndrome. Mean time to presentation of stroke, TIA, and encephalopathy was 1 day (range, 1-19 d) posttransplant. Mortality rate among non-infectious complications was 12/53 (22.6%). Infectious complications accounted for 32% of the 78 total episodes. We found 25 episodes in 24 patients: 17 herpes zoster (median, 268 d after HT), 3 CNS aspergillosis (median, 90 d after HT), 1 CNS toxoplasmosis and tuberculosis (51 d after HT), 1 pneumococcal meningitis (402 d after HT), and 2 Listeria meningitis (median, 108 d after HT). The 3 patients with CNS aspergillosis died. The mortality rate among patients with infectious neurologic complications was 12% (42.8% if the CNS was involved). When we compared the OKT3-ATG and daclizumab groups, we found that the incidence of non-infectious complications was 15.1% vs. 7.3%, respectively, and the incidence of infectious complications was 7.5% vs. 1.4%, respectively. All but 1 opportunistic infection occurred in the OKT3-ATG time period. In conclusion, a wide variety of neurologic complications affected 19.5% of HT recipients. Non-infectious causes clearly predominated, but infections still accounted for 32% of the episodes. New monoclonal induction therapies have contributed to diminished CNS opportunistic infections in our program.

Headache in kidney transplantation

The aim of this retrospective study was to determine the relevance of the symptom “headache” in kidney transplanted patients, since few studies have considered headache as a clinically significant complication in this condition. A total of 83 consecutive kidney transplant patients underwent to neurological examination and a detailed headache history was taken. The headache history considered the period before kidney disease, during renal failure, during dialysis treatment and after transplantation. Diagnosis was made according to International Headache Criteria (ICDH-II) (2004). Our results reveal an occurrence of headache after kidney transplantation in 44.5% of the patients, which is higher than rates reported for the general population and in the only specific comparable study on liver transplant patients. These data suggest the need for prospective studies to explore the causal mechanisms by which headache develops with frequency in kidney transplant patients, and in particular to determine the role of immunosuppressive therapy.

Neuromuscular diseases after cardiac transplantation

BACKGROUND

Cardiac transplantation is a therapeutic option in end-stage heart failure. Peripheral nervous system (PNS) disease is known to occur in cardiac transplant recipients but has not been fully characterized.

METHODS

This retrospective cohort review reports the PNS-related concerns of 313 cardiac transplant recipients (28% women, 8% children) over an 18-year period at a single institution.

RESULTS

Thirty percent of patients (95 of 313) reported a PNS-related concern in the post-transplant period, but only 5% had a concern in the first 6 weeks after transplant. The relative frequency of PNS-related complaints was as follows: polyneuropathy, 33%; muscle disease, 26%; mononeuropathy, 17%; radiculopathy, 13%; small-fiber polyneuropathy, 4%; plexopathy, 3%; and other (e.g., herpes zoster), 4%.

CONCLUSIONS

Etiology of these concerns can be divided into four broad categories: (1) immediate post-operative complications (e.g., brachial plexus stretch injury); (2) concerns related to the underlying disease prompting transplantation (e.g., polyneuropathy secondary to amyloidosis); (3) concerns related to necessary medications (e.g., steroid-associated myopathy); and (4) concerns reflective of aging in a post-transplant population with enhanced survival (e.g., degenerative joint disease-related radiculopathy).

Incidence of and Risk Factors for Neurologic Complications After Heart Transplantation

INTRODUCTION

Following heart transplantation (HT), neurologic complications occur in 50% to 70% of patients, mostly in the perioperative period. The objective of our study was to analyze the frequency and impact of factors related to the development of neurological complications after HT.

MATERIALS AND METHODS

HT patients with survival greater than 1 month (November 1987 to May 2003) were included. Heart-lung transplants, retransplants, and pediatric patients were excluded. Neurologic complications were defined as a neurologic event requiring hospitalization or detected in the hospital. Groups included ischemic or hemorrhagic stroke, seizures, neurotoxicity or other complications (e.g., infections, headaches, Alzheimer's).

RESULTS

We assessed 322 HT patients (87.6% men, 12.4% women) and grouped them according to the presence of neurologic complications during follow-up. There were no differences in the baseline characteristics between the two groups. Of patients the patients studied, 13.7% suffered a neurologic complication: ischemic stroke (3.5%), neurotoxicity (2.9%), seizures (1.9%), and other complications (1.6%). Only two cases of hemorrhagic stroke (0.6%) were observed. Associations with pretransplant risk factors included seizures with diabetes mellitus (OR, 6.54; 95% CI, 1.28 to 33.6, P = .024), seizures with renal failure (OR, 5.95; 95% CI, 1.03 to 34.3; P = .046), and ischemic stroke with prior valvular disease (OR, 4.96, 95% CI, 1.22 to 20.1; P = .045). Associations with pretransplant risk factors were neurologic complications with the number of infections (OR, 1.35, 95% CI, 1.05 to 1.73; P = .02). No differences were found in survival of patients with neurologic complications.

CONCLUSIONS

The incidence of neurologic complications in our series was 13.7%. The most frequent neurologic complication was ischemic stroke. Valvular disease as the underlying disease was associated with ischemic stroke. Diabetes mellitus and renal failure were associated with seizures. The number of posttransplant infections was associated with neurologic complications. There were no differences in survival of patients with neurologic complications.

Cerebrovascular disease as a complication of cardiac transplantation

BACKGROUND AND OBJECTIVES

To characterize the frequency, risk factors, clinical presentation and etiological subtypes of cerebrovascular diseases (CVD) following cardiac transplantation (CTX).

METHODS

In a retrospective review of our CTX database (period 1984-2002), we assessed demographic data, vascular risk factors, surgery and donor details. We classified ischemic stroke (IS) using the clinical criteria of the Oxfordshire Community Stroke Project and the etiological criteria of the TOAST study. Logistic regression analysis and survival curves were carried out.

RESULTS

CTX was performed in a total of 314 patients (age 46 +/- 14 years, 78% male) and mean follow-up was 54 +/- 57 months. Twenty-two patients (7%) presented CVD: hemorrhagic stroke in 12%, transient ischemic attack in 28% and IS in 60%. CVD were early postoperative (less than 2 weeks) in 20% of patients and late in 80%. The clinical presentation in patients with IS was total anterior circulation (23.1%), partial anterior (38.4%), lacunar (15.4%) and posterior circulation (23.1%), and the etiological classification was large artery atherosclerosis (15.4%), cardioembolism (14.4%), small vessel disease (15.4%), unusual causes (15.4%) and undetermined cause (38.4%). The only independent predictor of CVD was a prior CVD event with an odds ratio of 8.2 (95% CI, 2.2-30.2, p < 0.02). The estimated risk of CVD at 5 years was greater (p < 0.02) in patients with prior CVD (4.1%) than in those without (1.1%).

CONCLUSIONS

CVD are a relatively frequent complication after CTX (7%) and usually occur in the late postoperative phase. CVD prior to transplantation increase the risk of CVD after this procedure.

Neurologic complications after heart transplantation

OBJECTIVE

Neurologic complications are known as important cause of morbidity and mortality in orthotopic heart transplantation. Our aim was to identify the frequency and outcome of neurologic complications after heart transplantation in a prospective observational study.

METHOD

From September 93 to September 99, as part of our routine heart transplantation protocol all patients with end-stage cardiac failure were evaluated by the same neurologist before and at the time of any neurologic event (symptom or complaint) after transplantation.

RESULTS

Out of 120 candidates evaluated, 62 were successfully transplanted (53 male; median age 45.5 years, median follow-up 26.8 months). Fifteen patients (24%) had ischemic, 22 (35%) idiopathic, 24 (39%) Chagas' disease and 1 (2%) had congenital cardiomyopathy. Neurologic complications occurred in 19 patients (31%): tremor, severe headache, transient encephalopathy and seizures related to drug toxicity or metabolic changes in 13; peripheral neuropathy in 4; and spinal cord compression in two (metastatic prostate cancer and epidural abscess). No symptomatic postoperative stroke was observed.

CONCLUSIONS

Although frequent, neurologic complications were seldom related to persistent neurologic disability or death. Most of the complications resulted from immunosuppression, however, CNS infection was rare. The absence of symptomatic stroke in our series may be related to the lower frequency of ischemic cardiomyopathy.

Contrasting the neurologic complications of cardiac transplantation in adults and children

The objective of this study was to evaluate neurologic complications associated with cardiac transplantation and compare the neurologic complications seen in adults and children. As advances in immunology have led to longer survival times for cardiac transplant recipients (1- and 5-year survival rates have improved to 86% and 65%, respectively), a number of neurologic complications have emerged. We performed a 14-year retrospective review of all adults and children (<18 years old) who had orthotopic cardiac transplantation at either Indiana University Hospital or James Whitcomb Riley Hospital for Children. The rates of neurologic complications involving the central and peripheral nervous systems in adults and children were assessed for differences using the chi-square test and Fisher's exact test where appropriate. A total of 191 orthotopic cardiac transplants were performed from 1986 to 2000, with follow-up available for 184, including 107 adults and 77 children. Thirty-two of 107 (30%) adults experienced a total of 47 complications, with peripheral neuropathies being the most frequent complication. Eighteen of 77 (23%) children experienced a total of 22 complications, with seizures being the most frequent complication. Other complications occurring in both groups were cerebrovascular, infectious, encephalopathies, neoplasms, and "other." Neurologic complications in children and adults after orthotopic cardiac transplantation are similar in both incidence and type. However, peripheral neuropathies tend to occur more frequently in adults than in children (P = .04), and the types of complications in the immediate post-transplant period seem to differ.

Acute quadriplegic myopathy with loss of thick (myosin) filaments following heart transplantation

Acute quadriplegic myopathy with loss of thick (myosin) filaments (AQM-LTF) is an acute toxic myopathy observed in critically ill patients and is characterized by proximal or diffuse weakness of extremities and difficulty in weaning from mechanical ventilation. In recent years, this myopathy has been described in transplanted patients, although only 5 cases have been reported following heart transplantation. We present 3 new cases and review the previous literature. We conclude that the clinical picture and outcome of AQM-LTF in heart-transplanted patients do not differ from those observed in other critically ill patients (transplanted and non-transplanted). Therefore, because AQM-LTF is often clinically suspected muscle biopsy should be quickly performed to confirm the diagnosis so that physical therapy may begin as soon as possible.