QT interval in anorexia nervosa

Electrocardiographic QTc as a Surrogate Measure of Cardiac Risk in Children, Adolescents, and Young Adults With Eating Disorders

The study goal was to investigate electrocardiographic findings, including corrected QT interval (QTc), in patients aged 8 to 23 with eating disorders (EDs) at presentation, compared with an age-and sex-matched control population. We retrospectively reviewed 200 ED patients, and 200 controls. Blinded electrocardiograms (ECGs) were interpreted by an expert reader, and QT intervals corrected using the Bazett formula. Eating disorder patients were 89.5% female, with mean age 16.4 years and median percent median body mass index (BMI)-for-age (%mBMI)a of 91.1%. In ED patients, QTc was significantly shorter than controls (399.6 vs 415.0msec, P < .001). After adjusting for height, %mBMI, sex, magnesium level, and bradycardia, mean QTc duration in patients with anorexia nervosa-restricting subtype (AN-R) was significantly shorter than other ED patients (P = .010). Higher %mBMI was associated with shorter QTc duration (P = .041) after adjusting for height, magnesium, bradycardia, and Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) diagnosis. Within the ED group, no significant association was identified between QTc and medications, electrolytes, or inpatient status.

Early echocardiographic evaluation of children admitted to the emergency department for anorexia nervosa during the COVID-19 pandemic

PURPOSE

Anorexia nervosa (AN) is the most frequent eating disorder (ED), whose cardiac complications may have life-threatening consequences for both the physical and psychological health of affected children. In this study, we reported and analysed the echocardiographic anomalies found in pediatric patients diagnosed with AN.

METHODS

We reported the demographic and clinical characteristics of children aged 8 to 18 years, who were diagnosed with AN and underwent a complete cardiological evaluation at the Emergency Department of the Bambino Gesù Children's Hospital, IRCCS, Rome between the 1st January 2021 and the 30th June 2021. Furthermore, we compared the patients according to the presence of pericardial effusion and a BMI (body mass index) cut-off 14.5 kg/m2.

RESULTS

Forty-nine patients were included in the study. The mean age was 15.1 years. Most patients were female (89.8%). The mean length of hospitalization was 18 days. The mean BMI at admission was 14.8 kg/m2, with a median weight loss of 9 kg in the last year. Eleven patients (22.4%) presented with cardiovascular signs or symptoms at admission. Most patients had pericardial effusion on heart ultrasound, with a mean thickness of 6 mm (SD ± 4). The LV (left ventricle) thickness over age was significantly higher in patients with pericardial effusion, with a Z score of -2.0 vs -1.4 (p = 0.014). The administration of psychiatric drugs was significantly more frequent in patients with a lower BMI (37.5% vs 12%, p = 0.038).

CONCLUSION

Our study suggests that a non-urgent baseline echocardiographic evaluation with focus on left-ventricular wall thickness and mass in children with anorexia nervosa is advisable.

LEVEL III

Evidence obtained from cohort or case-control analytic studies.

Cardiac Complications Associated with Eating Disorders in Children: A Multicenter Retrospective Study

PURPOSE

Eating disorders often result in somatic complications, including cardiac abnormalities. Cardiac abnormalities may involve any part of the heart, including the cardiac conduction system, and can lead to sudden cardiac death. The current study aimed to evaluate the incidence of cardiac complications in pediatric patients with eating disorders and their associated factors.

METHODS

We retrospectively analyzed patients aged 10-18 years who were diagnosed with DSM-V (Diagnostic and Statistical Manual of Mental Disorder-V) eating disorders and underwent electrocardiography (ECG) and/or echocardiography between January 2015 and May 2020.

RESULTS

In total, 127 patients were included, of whom 113 (89.0%) were female. The median body mass index (BMI) was 15.05±3.69 kg/m². Overall, 74 patients (58.3%) had ECG abnormalities, with sinus bradycardia being the most common abnormality (91.9%). Patients with ECG abnormalities had significantly lower BMI (14.35±2.78 kg/m² vs. 16.06± 4.55 kg/m², p<0.001) than patients without ECG abnormalities, as well as lower phosphorus and higher cholesterol levels. Among the 46 patients who underwent echocardiographic evaluation, 23 (50.0%) had echocardiographic abnormalities, with pericardial effusion being the most common (60.9%). The median left ventricular mass (LVM) and ejection fraction were 67.97±21.25 g and 66.91±28.76%, respectively. LVM and BMI showed a positive correlation (r=0.604, p<0.001). After weight gain, the amount of pericardial effusion was reduced in 3 patients, and 30 patients presented with normal ECG findings.

CONCLUSION

Cardiac abnormalities are relatively frequent in patients with eating disorders. Physicians should focus on this somatic complication and careful monitoring is required.

Is the Activity-Based Anorexia Model a Reliable Method of Presenting Peripheral Clinical Features of Anorexia Nervosa?

Anorexia nervosa (AN) causes the highest number of deaths among all psychiatric disorders. Reduction in food intake and hyperactivity/increased anxiety observed in AN are also the core features of the activity-based anorexia animal model (ABA). Our aim was to assess how the acute ABA protocol mimics common AN complications, including gonadal and cardiovascular dysfunctions, depending on gender, age, and initial body weight, to form a comprehensive description of ABA as a reliable research tool. Wheel running, body weight, and food intake of adolescent female and male rats were monitored. Electrocardiography, heart rate variability, systolic blood pressure, and magnetic resonance imaging (MRI) measurements were performed. Immediately after euthanasia, tissue fragments and blood were collected for further analysis. Uterine weight was 2 times lower in ABA female rats, and ovarian tissue exhibited a reduced number of antral follicles and decreased expression of estrogen and progesterone receptors. Cardiovascular measurements revealed autonomic decompensation with prolongation of QRS complex and QT interval. The ABA model is a reliable research tool for presenting the breakdown of adaptation mechanisms observed in severe AN. Cardiac and hormonal features of ABA with underlying altered neuroendocrine pathways create a valid phenotype of a human disease.

QT Prolongation in Dialysis Patients: An Epidemiological Study with a Focus on Malnutrition

BACKGROUND/AIMS

QT prolongation is a known risk factor for ventricular fibrillation and ventricular tachycardia. Therefore, more refined management is necessary to reduce sudden cardiac death secondary to such arrhythmias.

METHODS

Electrocardiographic findings were reviewed in 224 patients, and the associations of QT prolongation with various clinical parameters were examined, including the nutritional state. Correlations were also examined between QT prolongation and body composition measurements determined by multifrequency bioelectrical impedance analysis.

RESULTS

Prolongation of the corrected QT (QTc) interval over 0.44 s was seen in 140 patients (62.5%). QT prolongation was independent of age and dialysis therapy duration and was more frequent in diabetics (70.1%) than in nondiabetics (54.2%, p = 0.014) and more frequent in women (78.8%) than in men (53.5%, p < 0.001). Serum levels of albumin (p < 0.001) and Cr (p < 0.001) and the Geriatric Nutritional Risk Index (GNRI, p < 0.001) were negatively correlated with QTc interval; no significant correlation was noted with total protein, urea nitrogen, or uric acid. Negative correlations with QTc interval were found for BMI(p < 0.01), percent total body water (%TBW; p < 0.05), and percent intracellular water (%ICW; p < 0.01) but not with the percent extracellular water/TBW ratio or edema ratio. The longer the QTc interval, the lower the fat-free mass (FFM; p < 0.01) and muscle mass (MM; p < 0.01), but there was no significant correlation with percent fat.

CONCLUSION

These results suggest that QT prolongation is a common complication and is more frequent in women and diabetic patients. The decreases in serum albumin and Cr levels, GNRI, BMI, %TBW, %ICW, FFM, and MM together coincided with malnutrition and thus suggest a close relationship of QT prolongation with malnutrition. Management of QT prolongation may be achieved better in the future by understanding these biochemical and biophysical changes, particularly those regarding malnutrition.

Heart rate variability as a biomarker for anorexia nervosa: A review

OBJECTIVE

Anorexia nervosa (AN) typically begins in early adolescence and other than weight status has few reliable biomarkers. Early diagnosis is a critical prognostic factor, but this can be clinically challenging. Heart rate variability (HRV), the beat-by-beat variance in heart rate (HR), may provide a unique assessment for the presence of AN because it has clinical utility as a biomarker of cardiac autonomic control in various populations (e.g., athletes, the aged, those with cardiovascular diseases, etc.). We present a review of the literature examining HRV in those with AN.

METHOD

Relevant publications were selected from PubMed using the search terms 'anorexia nervosa AND (HR OR HRV)'. Twenty papers were selected and reviewed.

RESULTS

The majority of studies suggest that those with AN have markedly and consistently elevated HRV compared to controls, even greater than among young athletes. However, no studies have explored HRV as a biomarker for AN.

DISCUSSION

Future studies on HRV should elucidate its role as a diagnostic biomarker for AN as well as its responsiveness with serial measurement to track response rates and predict relapse.

Refeeding syndrome: multimodal monitoring and clinical manifestation of an internal severe neurotrauma

Refeeding syndrome (RFS) is a rare, potentially life-threatening, condition seen in malnourished patients starting refeeding. RFS may provoke seizures and acute encephalopathy and can be considered an internal severe neurotrauma in need of specific treatment. The objective was to describe course of disease, treatment and, for the first time, multimodal monitoring output in a comatose patient suffering RFS. After gastric-banding and severe weight loss, the patient initiated self-starving and was transferred to our intensive care unit (ICU) following rapid refeeding. At arrival, seizures, decrease in consciousness (GCS 7) and suspected acute encephalitis was presented. Serum albumin was 8 g/l. Intracranial pressure (ICP), invasive blood pressure and electrocardiography (ECG) were monitored. Pressure reactivity (PR_x) and compliance (RAP) were calculated. The patient developed congestive heart failure, anuria and general oedema despite maximal neuro- and general ICU treatment. Global cerebral oedema and hypoperfusion areas with established ischemia were seen. ECG revealed massive cardiac arrhythmia and disturbed autonomic regulation. PR_x indicated intact autoregulation (-0.06 ± 0.18, mean ± SD) and relatively normal compliance (RAP = 0.23 ± 0.13). After 15 days the clinical state was improved, and the patient returned to the primary hospital. RFS was associated with serious deviations in homeostasis, high ICP levels, ECG abnormalities, kidney and lung affections. It is of utmost importance to recognize this rare syndrome and to treat appropriately. Despite the severe clinical state, cerebral autoregulation and compensatory reserve were generally normal, questioning the applicability of indirect measurements such as PR_x and RAP during neuro-intensive care treatment of RFS patients with cerebral engagement.

Long-term cardiac arrhythmia and chronotropic evaluation in patients with severe anorexia nervosa (LACE-AN): A pilot study

BACKGROUND

Anorexia nervosa (AN) is associated with autonomic dysfunction and carries a high risk of sudden death, putatively attributed to ventricular tachyarrhythmias. To date, long-term cardiac monitoring has not been performed to confirm this speculation.

METHODS AND RESULTS

We assessed the safety and acceptability of an insertable cardiac monitor (ICM) in patients with severe AN with markedly reduced body mass index (BMI), and investigated heart rate (HR) and rhythm before and after weight restoration. Autonomic function was assessed as HR response to a standardized activity protocol at baseline and four additional visits over 360 days. The Florida Patient Acceptance Survey (FPAS) was used to measure ICM acceptability. During a mean follow-up of 10 months, no ICM-related complications occurred and ICM was well-accepted by the 11 study participants (nine women, aged 19-59 years, baseline BMI = 12.7 ± 1.6 kg/m² ). Both resting and peak HR increased with weight restoration and were directly associated with BMI (both P < .001). No ventricular tachyarrhythmias occurred during the study period, but two participants (18%) experienced eight sinus pauses (3.0-7.0 seconds) and three runs of supraventricular tachycardia.

CONCLUSIONS

Long-term cardiac rhythm monitoring with an ICM is feasible, safe, and acceptable in patients with severe AN. Autonomic dysfunction in AN results in not only profound resting bradycardia, but also some degree of chronotropic incompetence, both of which improve with weight restoration. Clinically significant bradyarrhythmias are more common than ventricular tachyarrhythmias in AN, and may represent a competing underlying mechanism for the high risk of sudden death in this population.

Heart and anorexia nervosa

Anorexia nervosa, one of the more frequent and severe eating disorders, is a chronic psychiatric disease with potentially serious somatic consequences. This behavioral symptomatology leads to weight loss, undernutrition, and more or less severe-potentially life-threatening-somatic complications including respiratory, hepatic, digestive and cardiac features, electrolyte disturbances, endocrine and bone impairment, immunodepression, and related opportunistic infections. In this review, the authors report an overview of cardiac diseases in this disease.

QTc Interval and Risk of Cardiac Events in Adults With Anorexia Nervosa: A Long-Term Follow-Up Study

BACKGROUND

The literature contains several cases of anorexia nervosa (AN) patients with prolonged QTc interval. However, the risk of prolonged QTc interval is controversial and the risk of cardiac events in AN patients has yet to be investigated.

METHODS

We estimated the difference in mean QTc interval and relative risk of borderline prolonged QTc (>440 ms) and prolonged QTc (>460 ms) between 430 adult women AN patients and 123 healthy controls using 3 correction formulas. In a follow-up study, we estimated the risk of a primary end point (a composite of ventricular tachycardia, aborted cardiac arrest, and cardiac arrest) in AN patients compared with a population-based cohort derived from the Danish Civil Register.

RESULTS

Mean QTc for AN patients was 408 ms (Hodges), 402 ms (Fridericia), and 399 ms (Bazett). Hodges' found a slightly increased mean QTc (6.8 ms, 95% confidence interval, 1.6-12.0; P=0.01) and percentage with QTc >440 ms in AN patients (relative risk, 3.7, 95% confidence interval, 1.4-10.3; P=0.01), not observed with Fridericia's and Bazett's formulas. There was no difference in the risk of QTc >460 ms between AN patients and healthy controls. During a median follow-up of 10.1 years, AN patients had an increased risk of the primary end point compared with the population-based cohort (hazard ratio, 10.4, 95% confidence interval, 2.6-41.6; P=0.001). However, absolute numbers were small with cumulative incidences of 0.5% and 0.07%, respectively, after 10 years. No events occurred in any AN patient with QTc >440 ms. All-cause mortality was also significantly increased in AN patients compared with the population-based cohort (hazard ratio, 11.2, 95% confidence interval, 5.1-24.5; P<0.001).

CONCLUSIONS

Overall, there was no difference in mean QTc interval or risk of prolonged QTc between AN patients and healthy controls. However, AN patients had a notably increased all-cause mortality, as well as an increased risk of cardiac events, which was not related to the baseline QTc interval.

The Role of Cardiac Magnetic Resonance Imaging in Severe Anorexia Nervosa

Objective

Anorexia nervosa (AN) patients are at an increased risk of developing cardiac complications including bradyarrhythmias, systolic dysfunction, pericardial effusions, and sudden cardiac death. Although previous echocardiographic studies in AN patients have demonstrated a reduction in overall left ventricular (LV) mass, systolic dysfunction, and silent pericardial effusions, little is known about the role of cardiac magnetic resonance imaging (CMR) in assessing this patient population. The objective of this study was to assess cardiac indices and the presence of myocardial fibrosis in AN patients.

Methods

Between 2014 and 2015, a cross-sectional pilot study of 16 female patients who met the Diagnostic and Statistics Manual of Mental Disorders, fifth edition (DSM-5) criteria for AN was conducted at a single tertiary care center. Baseline characteristics including age, weight, food restriction behavior, over-exercise, self-induced vomiting, and laxative abuse were collected in the study population. Electrocardiography, transthoracic echocardiography (TTE), and CMR were performed.

Results

The mean age was 17 years (range: 13-22 years). There were no conduction abnormalities as the average PR interval was 152 ms (range: 130-190 ms) and QTc was 413 ms (range: 360-450 ms). Using TTE, the left ventricular ejection fraction (LVEF) was 54 ± 4% with a lower LV mass/body surface area (BSA) of 56 ± 7g/m² in AN patients as compared to controls. Using CMR, both the mean LVEF of 52 ± 9% and LV mass/BSA of 45 ± 4g/m² were lower in AN patients as compared to controls. Using CMR, both right ventricular ejection fraction (RVEF) of 50 ± 10% and a right ventricular (RV) mass/BSA of 18 ± 3g/m² were smaller in AN patients as compared to controls. There was no evidence of late gadolinium enhancement (LGE) in the study population.

Conclusions

Young patients with AN have lower cardiac mass and volumes with no evidence of myocardial fibrosis.

QT interval and dispersion in drug-free anorexia nervosa adolescents: a case control study

Long QT values have been reported in patients with anorexia nervosa of the restricting type (ANr) potentially increasing the risk of fatal arrhythmia, especially if psychotropic drug treatment is required. Nevertheless, the previous studies on this topic are biased by drug exposure, long disease durations, and small sample sizes. This study is aimed at assessing QTc and QTcd values in ANr adolescents with recent onset and drug free, as compared to subjects affected by psychiatric disorders other than ANr. We evaluated QTc and its dispersion (QTcd) in a population of 77 drug-free ANr female adolescents and compared to an equal number of healthy controls (H-CTRL) and pathological controls (P-CTRL, mixed psychiatric disorders). The QT determination was performed on a standard simultaneous 12-lead ECG in blind by a single experienced investigator. QTc was calculated by the Bazett's formula and QTcd was determined as the difference between the maximum and minimum QTc intervals in different leads. Only for ANr patients, clinico-demographic data, hormones, and electrolytes were obtained. QTc was slightly reduced in ANr patients (27.7 ms, < 10%, p < 0.0003) vs. controls, while QTcd was increased in P-CTRL (30%, p < 0.0003). Heart rate was significantly lower in ANr patients vs. controls (25%; p < 0.003). Tyroid hormones and serum potassium showed weak although significant positive correlations with QTc in ANr patients. QTcd displayed a weak negative correlation with the BMI percentile (r = - 0.262, p = 0.03). We reject the hypothesis that QTc and QTcd are increased in drug-free ANr adolescents with a relatively short-disease duration. Further studies are needed to understand if the previously reported increase might be related to other associated chronic disorders, such as hormonal or electrolyte imbalance.

Low body mass index correlates with low left ventricular mass index in patients with severe anorexia nervosa

The patients with anorexia nervosa (AN) are known to be associated with high mortality, but the actual causes of death are still undefined. We tested the hypothesis that AN patients had cardiac disorders, including left ventricular (LV) dysfunction and LV atrophy. This study is a cross-sectional study at St. Luke's International Hospital, Tokyo. We analyzed 13 female inpatients with AN. We assessed cardiac function and heart volume in AN by echocardiography, LV ejection fraction (LVEF), LV mass, and LV mass index (LVMI). We assessed the correlations between body mass index (BMI) and heart volume (LV mass and LVMI). The mean age and BMI were 34.8 ± 11.2 years and 15.5 ± 3.1 kg/m², respectively. There was no patient with mitral valve prolapse, but 3 patients had trivial to small amount of pericardial effusion. The mean LVEF was 67.7 ± 6.5%, and 12 out of 13 patients had normal LVEF. Their LV mass (89.0 ± 27.3 g) and LVMI (66.3 ± 16.4 g/m²) were small. BMI positively correlated with LVMI (r = 0.58, p = 0.040), as well as LV mass (r = 0.74, p = 0.004). Lower BMI reflects lower LVMI, as well as smaller LV mass. These issues suggest that heart volume is initially decreased in severe AN conditions. Low LVMI could be a good marker of severity of AN.

Cardiac changes in anorexia nervosa

Introduction Anorexia nervosa is an eating disorder, which is associated with many different medical complications as a result of the weight loss and malnutrition that characterise this illness. It has the highest mortality rate of any psychiatric disorder. A large portion of deaths are attributable to the cardiac abnormalities that ensue as a result of the malnutrition associated with anorexia nervosa. In this review, the cardiac complications of anorexia nervosa will be discussed.

METHODS

A comprehensive literature review on cardiac changes in anorexia nervosa was carried out.

RESULTS

There are structural, functional, and rhythm-type changes that occur in patients with anorexia nervosa. These become progressively significant as ongoing weight loss occurs.

CONCLUSION

Cardiac changes are inherent to anorexia nervosa and they become more life-threatening and serious as the anorexia nervosa becomes increasingly severe. Weight restoration and attention to these cardiac changes are crucial for a successful treatment outcome.

Cardiovascular complications of anorexia nervosa: A systematic review

OBJECTIVE

Anorexia nervosa portends the highest mortality among psychiatric diseases, despite primarily being a disease of adolescents and younger adults. Although some of this mortality risk is attributable to suicide, many deaths are likely cardiovascular in etiology. Recent studies suggest that adverse myocardial structural changes occur in this condition, which could underlie the increased mortality. Given limited prevalence of severe anorexia there is a paucity of clinical and autopsy data to discern an exact cause of death.

METHODS

Given this background we conducted a systematic review of the medical literature to provide a contemporary summary of the pathobiologic sequelae of severe anorexia nervosa on the cardiovascular system. We sought to elucidate the impact of anorexia nervosa in four cardiovascular domains: structural, repolarization/conduction, hemodynamic, and peripheral vascular.

RESULTS

A number of cardiac abnormalities associated with anorexia nervosa have been described in the literature, including pericardial and valvular pathology, changes in left ventricular mass and function, conduction abnormalities, bradycardia, hypotension, and dysregulation in peripheral vascular contractility. Despite the prevalent theory that malignant arrhythmias are implicated as a cause of sudden death in this disorder, data to support this causal relationship are lacking.

DISCUSSION

It is reasonable to obtain routine electrocardiography and measurements of orthostatic vital signs in patients presenting with anorexia nervosa. Echocardiography is generally not indicated unless prompted by clinical signs of disease. Admission to an inpatient unit with telemetry monitoring is recommended for patients with severe sinus bradycardia or junction rhythm, marked prolongation of the corrected QT interval, or syncope.

Refeeding Low Weight Hospitalized Adolescents With Anorexia Nervosa: A Multicenter Randomized Controlled Trial

BACKGROUND

Refeeding patients with anorexia nervosa (AN) is associated with high morbidity and mortality. A lack of evidence from interventional studies has hindered refeeding practice and led to worldwide disparities in management recommendations. In the first randomized controlled trial in this area, we tested the hypothesis that refeeding adolescents with AN with a higher energy intake than what many guidelines recommend improved anthropometric outcomes without adversely affecting cardiac and biochemical markers associated with refeeding.

MATERIALS AND METHODS

Participants aged 10-16 years with a body mass index (BMI) <78% of the median (mBMI) for age and sex were recruited from 6 UK hospitals and randomly allocated to start refeeding at 1200 kcal/d (n = 18, intervention) or 500 kcal/d (n = 18, control).

RESULTS

Compared with controls, adolescents randomized to high energy intake had greater weight gain (mean difference between groups after 10 days of refeeding, -1.2% mBMI; 95% confidence interval, -2.4% to 0.0%; P = .05), but randomized groups did not differ statistically in QTc interval and other outcomes. The nadir in postrefeeding phosphate concentration was significantly related to percentage mBMI at the start of refeeding (baseline; P = .04) and baseline white blood cell count (P = .005) but not to baseline energy intake (P = .08).

CONCLUSIONS

Refeeding adolescents with AN with a higher energy intake was associated with greater weight gain but without an increase in complications associated with refeeding when compared with a more cautious refeeding protocol-thus challenging current refeeding recommendations.

Characterization of Myocardial Repolarization Reserve in Adolescent Females With Anorexia Nervosa

BACKGROUND

Patients with anorexia nervosa exhibit abnormal myocardial repolarization and are susceptible to sudden cardiac death. Exercise testing is useful in unmasking QT prolongation in disorders associated with abnormal repolarization. We characterized QT adaptation during exercise in anorexia.

METHODS AND RESULTS

Sixty-one adolescent female patients with anorexia nervosa and 45 age- and sex-matched healthy volunteers performed symptom-limited cycle ergometry during 12-lead ECG monitoring. Changes in the QT interval during exercise were measured, and QT/RR-interval slopes were determined by using mixed-effects regression modeling. Patients had significantly lower body mass index than controls; however, resting heart rates and QT/QTc intervals were similar at baseline. Patients had shorter exercise times (13.7±4.5 versus 20.6±4.5 minutes; P<0.001) and lower peak heart rates (159±20 versus 184±9 beats/min; P<0.001). The mean QTc intervals were longer at peak exercise in patients (442±29 versus 422±19 ms; P<0.001). During submaximal exertion at comparable heart rates (114±6 versus 115±11 beats/min; P=0.54), the QTc interval had prolonged significantly more in patients than controls (37±28 versus 24±25 ms; P<0.016). The RR/QT slope, best described by a curvilinear relationship, was more gradual in patients than in controls (13.4; 95% confidence interval, 12.8-13.9 versus 15.8; 95% confidence interval, 15.3-16.4 ms QT change per 10% change in RR interval; P<0.001) and steepest in patients within the highest body mass index tertile versus the lowest (13.9; 95% confidence interval, 12.9-14.9 versus 12.3; 95% confidence interval, 11.3-13.3; P=0.026).

CONCLUSIONS

Despite the absence of manifest QT prolongation, adolescent anorexic females have impaired repolarization reserve in comparison with healthy controls. Further study may identify impaired QT dynamics as a risk factor for arrhythmias in anorexia nervosa.

The prevalence of long QT interval in post-operative intensive care unit patients

The severity of patient illnesses and medication complexity in post-operative critically ill patients increase the risk for a prolonged QT interval. We determined the prevalence of prolonged QTc in surgical intensive care unit (SICU) patients. We performed a prospective cross-sectional study over a 15-month period at a major academic center. SICU pre-admission and admission EKGs, patient demographics, and laboratory values were analyzed. QTc was evaluated as both a continuous and dichotomous outcome (prolonged QTc > 440 ms). 281 patients were included in the study: 92 % (n = 257) post-operative and 8 % (n = 24) non-operative. On pre-admission EKGs, 32 % of the post-operative group and 42 % of the non-operative group had prolonged QTc (p = 0.25); on post-admission EKGs, 67 % of the post-operative group but only 33 % of the non-operative group had prolonged QTc (p < 0.01). The average change in QTc in the post-operative group was +30.7 ms, as compared to +2 ms in the non-operative group (p < 0.01). On multivariable adjustment for long QTc as a dichotomous outcome, pre-admission prolonged QTc (OR 3.93, CI 1.93-8.00) and having had an operative procedure (OR 4.04, CI 1.67-9.83) were associated with developing prolonged QTc. For QTc as a continuous outcome, intra-operative beta-blocker use was associated with a statistically-significant decrease in QTc duration. None of the patients developed a lethal arrhythmia in the ICU. Prolonged QTc is common among post-operative SICU patients (67 %), however lethal arrhythmias are uncommon. The operative experience increases the risk for long QTc.

Implantable cardioverter-defibrillator therapy in a 34-year-old patient with eating disorders and after the third sudden cardiac arrest

Eating disorders (ED) such as anorexia nervosa and bulimia are psychiatric diseases associated with the highest mortality rate of any other psychiatric disorders. More recently, long-term outcome studies with follow-up of over 20 years report a mortality of between 15% and 18% (Casiero and Frishman, Cardiol Rev 14(5), 227, 2006). The sudden death secondary to arrhythmias is often the cause of death in these patients (Casiero and Frishman, Cardiol Rev 14(5), 227, 2006). A case of life-threatening ventricular arrhythmia (VA) in a patient with ED is presented. Clinical records (cardiologic, psychiatric), electrocardiograms, echocardiogram, coronary angiogram, cardiac magnetic resonance, and endocrine diagnostics were performed. Finally a cardioverter-defibrillator (ICD) was implanted in the patient after her third cardiac arrest. An optimal approach to antiarrhythmic therapy in such patients is a real challenge for a cardiologist.

Dispersion durations of P-wave and QT interval in children treated with a ketogenic diet

BACKGROUND

Limited data are available on the effects of a ketogenic diet on dispersion duration of P-wave and QT-interval measures in children. We searched for the changes in these measures with serial electrocardiograms in patients treated with a ketogenic diet.

METHODS

Twenty-five drug-resistant patients with epilepsy treated with a ketogenic diet were enrolled in this study. Electrocardiography was performed in all patients before the beginning and at the sixth month after implementation of the ketogenic diet. Heart rate, maximum and minimum P-wave duration, P-wave dispersion, and maximum and minimum corrected QT interval and QT dispersion were manually measured from the 12-lead surface electrocardiogram.

RESULTS

Minimum and maximum corrected QT and QT dispersion measurements showed nonsignificant increase at month 6 compared with baseline values. Other previously mentioned electrocardiogram parameters also showed no significant changes.

CONCLUSIONS

A ketogenic diet of 6 months' duration has no significant effect on electrocardiogram parameters in children. Further studies with larger samples and longer duration of follow-up are needed to clarify the effects of ketogenic diet on P-wave dispersion and corrected QT and QT dispersion.

Assessment of myocardial damage by cardiac MRI in patients with anorexia nervosa

OBJECTIVE

Cardiac damage is a major complication of anorexia nervosa (AN). The present study evaluated the prevalence of myocardial damage in patients with AN by cardiac magnetic resonance imaging (CMR).

METHOD

This study was cross-sectional and observational. Forty consecutive female patients with a diagnosis of AN and 28 healthy female subjects were evaluated from January 2007 to 2011 at the Department of Psychiatry (University of Istanbul, Istanbul, Turkey). Following enrollment in the study, participants underwent a cardiac evaluation, a physical examination, a standard electrocardiogram (ECG), an echocardiography and a CMR.

RESULTS

Body weight, body mass index and heart rate values were lower in patients with AN than in the control group. When compared with control groups, patients with AN showed reduced left ventricular mass with normal systolic function. Compared to control subjects, patients with AN had higher prevalence of pericardial effusion (30% in the AN group, 4% in the control group, p = .005) and mitral valve prolapses (23% in the AN group, 4% in the control group, p = .03). Myocardial fibrosis (detected as late gadolinium enhancement on CMR) was found in 23% of patients with AN. Myocardial fibrosis was not detected in any control subject (p = .007).

CONCLUSION

A strong association was found between myocardial fibrosis and AN. Cardiac damage of myocardial fibrosis in asymptomatic patients with AN can be found by CMR examination.

Psychotropic drug prescribing in an Australian specialist child and adolescent eating disorder service: a retrospective study

BACKGROUND

To describe the rates, indications, and adverse effects of psychotropic drug prescription in a specialist tertiary hospital child and adolescent eating disorder service.

METHODS

Retrospective case note study of all active eating disorder patients (N = 115) over the period of treatment from referral to time of study (M = 2 years), covering patient demographics, clinical characteristics, drug prescriptions, indications, and adverse effects.

RESULTS

Psychotropic drugs were prescribed in 45% of cases, most commonly antidepressants (41%), followed by anxiolytics (29%) and antipsychotics (22%), with 8% initiated before referral to the specialist eating disorder program. Common indications were depressed mood, agitation, anxiety, and insomnia. Patient clinical severity and complexity was associated with prescribing. Adverse effects, mostly minor, were recorded in 23% of antidepressant prescriptions, 39% of antipsychotic prescriptions, and 13% of anxiolytic prescriptions. Second generation antipsychotic prescription was associated with subsequent new onset binge eating, in this preliminary observational study. Self-harm by overdose of psychotropics occurred in 11% of patients prescribed medication.

CONCLUSIONS

Psychotropic medications were frequently prescribed to adolescent eating disorder patients to treat distressing symptoms. Prospective randomised controlled trials to clarify efficacy and safety are needed. Given the difficulties of conducting clinical trials in this population, services are encouraged to monitor and audit medication safety and efficacy in everyday practice, and to report their findings.

Long-term consequences of anorexia nervosa

Anorexia nervosa (AN) is a psychiatric disorder that occurs mainly in female adolescents and young women. The obsessive fear of weight gain, critically limited food intake and neuroendocrine aberrations characteristic of AN have both short- and long-term consequences for the reproductive, cardiovascular, gastrointestinal and skeletal systems. Neuroendocrine changes include impairment of gonadotropin releasing-hormone (GnRH) pulsatile secretion and changes in neuropeptide activity at the hypothalamic level, which cause profound hypoestrogenism. AN is related to a decrease in bone mass density, which can lead to osteopenia and osteoporosis and a significant increase in fracture risk in later life. Rates of birth complications and low birth weight may be higher in women with previous AN. The condition is associated with fertility problems, unplanned pregnancies and generally negative attitudes to pregnancy. During pregnancy, women with the condition have higher rates of hyperemesis gravidarum, anaemia and obstetric complications, as well as impaired weight gain and compromised intrauterine foetal growth. It is reported that 80% of AN patients are affected by a cardiac complications such as sinus bradycardia, a prolonged QT interval on electrocardiography, arrythmias, myocardial mass modification and hypotension. A decrease in bone mineral density (BMD) is one of the most important medical consequences of AN. Reduced BMD may subsequently lead to a three- to seven-fold increased risk of spontaneous fractures. Untreated AN is associated with a significant increase in the risk of death. Better detection and sophisticated therapy should prevent the long-term consequences of this disorder. The aims of treatment are not only recovery but also prophylaxis and relief of the long-term effects of this disorder. Further investigations of the long-term disease risk are needed.

ED management of patients with eating disorders

BACKGROUND

Eating disorders are one of the "great masqueraders" of the twenty-first century. Seemingly healthy young men and women with underlying eating disorders present to emergency departments with a myriad of complaints that are not unique to patients with eating disorders. The challenge for the Emergency Medicine physician is in recognizing that these complaints result from an eating disorder and then understanding the unique pathophysiologic changes inherent to these disorders that should shape management in the emergency department.

OBJECTIVE

In this article, we will review, from the perspective of the Emergency Medicine physician, how to recognize patients with anorexia and bulimia nervosa, the medical complications and psychiatric comorbidities, and their appropriate management.

CONCLUSIONS

Anorexia and bulimia nervosa are complex psychiatric disorders with significant medical complications. Recognizing patients with eating disorders in the ED is difficult, but failure to recognize these disorders, or failure to manage their symptoms with an understanding of their unique underlying pathophysiology and psychopathology, can be detrimental to the patient. Screening tools, such as the SCOFF questionnaire, are available for use by the EM physician. Once identified, the medical complications described in this article can help the EM physician tailor management of the patient to their underlying pathophysiology and effectuate a successful therapeutic intervention.

Normal late ventricular potentials in hospitalized patients with eating disorders

OBJECTIVE

Eating disorders, in particular anorexia nervosa (AN), are associated with cardiovascular complications and risk of arrhythmias. In a recent published study, it was found that patients with eating disorders, especially those affected by bulimia nervosa (BN) and a history of AN have abnormal late ventricular potentials (LPs). LPs are electrocardiographic markers used in detecting abnormal depolarization and increased risk of arrhythmias. Given the paucity of knowledge regarding the affects of eating disorders on cardiac depolarization, our aim was to further explore LPs in patients with eating disorders.

METHOD

The study group included 30 hospitalized patients with eating disorders (14 with AN, 10 with BN with no history of AN, and 6 with BN and history of AN). Signal averaged electrocardiography was conducted on all patients using the Frank corrected orthogonal lead system.

RESULTS

No patient with either eating disorder tested positive for LPs.

DISCUSSION

Hospitalized patients with eating disorders, medically monitored and treated for several weeks, had normal serum electrolytes, started to normalize their weight, and did not appear to be prone to arrhythmias associated with abnormal depolarization. The prognostic significance of LPs in risk stratification of patients with eating disorders should be further evaluated by large cohort studies and longer follow-up studies.

Factors influencing QT prolongation in patients hospitalized with severe anorexia nervosa

BACKGROUND

Anorexia nervosa (AN) carries the highest mortality of any psychiatric disorder largely attributable to sudden cardiac death and suicide. Controversy exists regarding the underlying mechanism of cardiac risk, whether QT prolongation is a consistent feature of the disorder and whether repolarization varies by disease severity. Some of the uncertainty may relate to a lack of standardized electrocardiography (ECG). To date, studies have not utilized centrally adjudicated digital ECG, and most have relied on the Bazett formula for rate-correction, which is suboptimal at the extremes of heart rate often observed in AN.

METHODS

We evaluated a hospitalized cohort of medically compromised, very-low-body mass index (BMI) AN patients. The QT interval was measured with high-precision calipers by a single, blinded electrophysiologist and rate corrected (QTc) using the Fridericia formula. Anatomically corrected left ventricular (LV) mass and resting energy expenditure (REE) were calculated as proxies for disease severity. Proportions exceeding categorical thresholds for QTc prolongation and correlations between admission QTc and disease severity were performed.

RESULTS

Among 19 patients, mean BMI was 12.3 kg/m(2), and 95% were female. The majority (68%) of patients were receiving QT-prolonging drugs. Four patients (21%) had QTc prolongation. Two of these patients (10.5%) exceeded the 500 ms threshold for marked QTc-prolongation, though each had concomitant factors contributing to delayed repolarization. The QTc interval was not significantly correlated with LV mass, LV mass index, BMI or REE.

CONCLUSIONS

Although delayed cardiac repolarization was observed among a medically compromised cohort of patients with anorexia nervosa, the QTc interval was not a reliable correlate of disease severity despite digital ECG adjudication and optimal rate correction.

QT variability among weight-restored patients with anorexia nervosa

OBJECTIVE

Anorexia nervosa (AN) may be complicated by cardiac arrhythmias and sudden death. A single study reported an increased QT variability index (QTVI), a marker for cardiac arrhythmogenicity, in AN patients. The aim of the current study was to further evaluate repolarization dynamics in a large cohort of patients with AN without electrolyte abnormalities and to evaluate previously unreported repolarization dynamics parameters.

METHODS

Forty-three AN patients and 45 age- and sex-matched controls were included in the study. Twenty-nine AN patients were hospitalized for a mean time of 1.5±1.1 months. The rest were ambulatory AN patients. Electrocardiograms were conducted under strict standards. QT variability index, normalized QT variability (QTVN) and power spectral analysis of QT dynamics were conducted with designated computer software.

RESULTS

None of the patients had an electrolyte imbalance. Although mean QT was higher in AN patients compared with controls, QTc results were similar following corrections for RR interval. There was no significant difference in QTVI, QTVN and power spectral analysis parameters among groups. The results of QTVI and QTVN were comparable to those previously published for healthy individuals. During 3 years of follow-up, no patient developed arrhythmias or suddenly died.

CONCLUSIONS

Medically treated AN patients who gained weight and had normal serum electrolytes appeared to have normal QTc and QT variability indexes, reflecting a nonincreased risk for cardiac arrhythmias. We suggest that weight normalization, medical treatment and lack of electrolyte abnormalities are responsible in part for these results. Further evaluation of the prognostic significance of QTVI and QTVN in AN is warranted.

The ketogenic diet and the QT interval

Cardiac complications have been rarely reported associated with the ketogenic diet. Prolonged QT interval in the electrocardiogram and torsades de pointes arrhythmias have been described in a few cases. The effect of the ketogenic diet on QT interval has not been systematically evaluated. We obtained serial electrocardiograms in our patients on the ketogenic diet to look for changes in the mean QT interval. Twenty seven children aged 6 months to 5 years with refractory epilepsy were enrolled. Classic ketogenic diet was introduced using a non-fasting gradual initiation protocol. All patients were supplemented with oral calcium and selenium. Electrocardiograms were obtained at baseline and after 1, 3, 6, and 12 months on the ketogenic diet. There was no statistically significant change in the corrected QT interval over time. There were no ST segment changes or dysrhythmias in any of the electrocardiograms.

Olanzapine use for the adjunctive treatment of adolescents with anorexia nervosa

OBJECTIVE

To examine assessment and treatment profiles of adolescent patients with anorexia nervosa and eating disorder not otherwise specified who received olanzapine as compared with an untreated matched sample.

METHOD

A retrospective, matched-groups comparison study was completed. Medical files of 86 female patients treated in the eating disorder program at the Children's Hospital of Eastern Ontario were examined. Patients treated with olanzapine were initially identified through chart review and then matched to a diagnosis, age, and, when possible, treatment group that served as the active comparator. Weight gain was examined in a sample of 22 inpatients.

RESULTS

Patients treated with olanzapine displayed greater evidence of psychopathology and medical compromise at the time of first assessment compared with those not treated. Rate of weight gain was not statistically different between groups when olanzapine was started during inpatient admissions. Medication effect on eating disorder cognitions could not be assessed given the presence of multiple confounders relating to treatment. Notable side effects included sedation and dyslipidemia in 56% of patients.

CONCLUSIONS

Despite our best attempts at matching olanzapine-treated subjects with a control sample, analysis revealed significant differences between groups, suggesting greater illness severity in those augmented with olanzapine. Given these inherent differences, we were unable to draw any firm conclusions regarding the potential efficacy of olanzapine. Factors associated with the prescription of adjunctive pharmacotherapy in this cohort appear to be linked to illness severity, acuity, and associated comorbidity. The observed side-effect profile indicates the need for more consistent predrug screening and for closer monitoring during treatment.

Malnutrition and hemodynamic status in adolescents hospitalized for anorexia nervosa

OBJECTIVE

To determine the effects of malnutrition on hemodynamic status of adolescents hospitalized for anorexia nervosa.

DESIGN

Longitudinal observational study.

SETTING

Tertiary care pediatric hospital. Patients Thirty-eight adolescents with anorexia nervosa, aged 13 to 21 years, with a mean (SD) body mass index (calculated as weight in kilograms divided by height in meters squared) of 15.9 (1.8). Intervention Subjects received standard care, including bed rest and graded nutritional therapy. A subsample of subjects (n=19) returned 11 to 57 weeks following hospitalization for a second cardiac evaluation.

MAIN OUTCOME MEASURES

Results from a 15-lead electrocardiogram, echocardiogram, treadmill stress test, and spinal bone mineral density measurement.

RESULTS

On admission, 26 subjects (68%) had sinus bradycardia. Bradycardia was less common in participants with a longer duration of illness (P=.04). Left ventricle mass was lower than predicted for age (Z score<-1.0) in 11 subjects (31%). Exercise tolerance was normal by all measures. Both heart rate and QT interval were predictors of spinal bone mineral density. In those who returned for follow-up, absolute measures of left ventricle mass did not change (P=.27). However, the corresponding Z scores declined over time (mean [SD] change, -0.9 [1.3]; P=.02).

CONCLUSIONS

In acutely malnourished adolescents with anorexia nervosa, few truly pathologic cardiac findings were identified. Sinus bradycardia was observed in most cases. Mild reductions in left ventricle mass and left ventricle function were seen both at baseline and at follow-up, suggesting early sparing of cardiac muscle in the face of moderate malnutrition as well as a relative delay of cardiac muscle restoration. The association of hemodynamic status with altered spinal bone mineral density emphasizes the range of systems affected by malnutrition in anorexia nervosa.

Prolonged QT interval in a man with anorexia nervosa

Anorexia nervosa is an eating disorder characterized by the avoidance of food intake, which usually leads to a weight loss. Cardiac co-morbility is common and we can find sometimes a mass loss from the left ventricle, which can be seen by echocardiography. But the commonest complications are rhythm variations, typically bradycardia with a prolonged QT interval in up to a 40% of the cases, which altogether elevates ventricular tachycardia and sudden death risk. We present the case of a male who was diagnosed with anorexia nervosa and developed asthenia, a long QT interval and also a severe both hypokalaemia and hypomagnesaemia. We intend to discuss the pathogenic paths as well as prophylactic and therapeutic measures to this potentially-lethal pathology.

Heart rate and catecholamine contribution to QT interval shortening on exercise

BACKGROUND

QT interval shortens with exercise. Some of this shortening is due to an increase in heart rate, and some is due to other effects of exercise, probably mostly neuroendocrine effects. Data from subjects with cardiac transplants have suggested that non-heart rate-related changes in QT interval on exercise are due to the effects of circulating catecholamines.

HYPOTHESIS

We sought to determine whether changes in plasma catecholamine levels with exercise are an important contributor to non-heart rate-related QT interval shortening.

METHODS

Subjects with DDD pacemakers were recruited. Subjects had QT intervals measured at rest, during a low fixed level exercise test designed to increase heart rate to about 110 beats/min, and, after resting, during pacing at a heart rate of 110 beats/min. Catecholamine levels were measured at each stage of the study.

RESULTS

QT interval at rest was 420 +/- 12 ms, during pacing 366 +/- 16 ms, and on exercise 325 +/- 14 ms. This then gave the proportion of QT interval shortening due to heart rate as 68.6 +/- 9.3% of total QT shortening, with the range between 35 and 95.6%. There was no proportionality between the degree of QT interval shortening on exercise that was not due to increases in heart rate and changes in plasma catecholamine levels.

CONCLUSION

Two-thirds of exercise-induced QT interval shortening are due to an increase in heart rate, and one-third to other effects. Changes in plasma catecholamine levels on exercise were not closely related to changes in the QT interval on exercise.

Sudden cardiac death in association with the ketogenic diet

The ketogenic diet is a high-fat, low-carbohydrate, adequate-protein diet that is used to decrease the frequency of seizures in patients who have refractory epilepsy. Despite its positive effects in some patients, there are potential adverse effects. Two complications related to the ketogenic diet are selenium deficiency, which has been associated with impaired myocardial function, and QT prolongation as documented on electrocardiography. Reported here are two cases of death in a child on the ketogenic diet for seizure control. In case 1, the child who died of complications related to torsade de pointes, with documented QT prolongation; post mortem examination revealed selenium-deficiency cardiomyopathy. In case 2, a child experienced QT prolongation while on the ketogenic diet and later died suddenly at home. Both children exhibited selenium deficiency. These two cases suggest that patients on the ketogenic diet require monitoring of the QT interval by electrocardiography, myocardial function by echocardiography, and selenium levels before and during the ketogenic diet.

A meta-analysis of heart rate and QT interval alteration in anorexia nervosa

OBJECTIVE

Reports have suggested association between sudden death and QT prolongation in AN patients. Incidence and clinical consequences of cardiac abnormalities remain controversial. As the course of AN disease is long-lasting it remains unclear how often psychiatrists should send AN patients for somatic and especially cardiological investigation. The objective of the study was to aggregate the published data on HR and QT alteration and to perform a meta-analysis of the HR and QT alteration in patients with anorexia nervosa.

METHODS

A Medline search of all English language studies from 1994 to 2005 was performed. The inclusion criteria were confirmed diagnosis of AN, measurement of QTc and mean heart rate. Data from 10 studies were analyzed using weighted linear regression model.

RESULTS

Analysis showed that bradycardia and relationship between HR and BMI decreases as the disease continues. QTc interval in AN patients was within normal range although significantly longer than in controls.

CONCLUSION

Further investigations of sudden death in patients with AN due to cardiac arrest are needed and a model of clinical monitoring of cardiovascular system should be elaborated. If QTc prolongation is detected even in the normal range further cardiological examination for risk assessment and systematic clinical surveillance of the cardiovascular system should be considered.

National athletic trainers' association position statement: preventing, detecting, and managing disordered eating in athletes

OBJECTIVE

To present recommendations for the prevention, detection, and comprehensive management of disordered eating (DE) in athletes.

BACKGROUND

Athletes with DE rarely self-report their symptoms. They tend to deny the condition and are often resistant to referral and treatment. Thus, screenings and interventions must be handled skillfully by knowledgeable professionals to obtain desired outcomes. Certified athletic trainers have the capacity and responsibility to play active roles as integral members of the health care team. Their frequent daily interactions with athletes help to facilitate the level of medical surveillance necessary for early detection, timely referrals, treatment follow-through, and compliance.

RECOMMENDATIONS

These recommendations are intended to provide certified athletic trainers and others participating in the health maintenance and performance enhancement of athletes with specific knowledge and problem-solving skills to better prevent, detect, and manage DE. The individual biological, psychological, sociocultural, and familial factors for each athlete with DE result in widely different responses to intervention strategies, challenging the best that athletics programs have to offer in terms of resources and expertise. The complexity, time intensiveness, and expense of managing DE necessitate an interdisciplinary approach representing medicine, nutrition, mental health, athletic training, and athletics administration in order to facilitate early detection and treatment, make it easier for symptomatic athletes to ask for help, enhance the potential for full recovery, and satisfy medicolegal requirements. Of equal importance is establishing educational initiatives for preventing DE.

Nutrition in clinical practice—the refeeding syndrome: illustrative cases and guidelines for prevention and treatment

The refeeding syndrome is a potentially lethal complication of refeeding in patients who are severely malnourished from whatever cause. Too rapid refeeding, particularly with carbohydrate may precipitate a number of metabolic and pathophysiological complications, which may adversely affect the cardiac, respiratory, haematological, hepatic and neuromuscular systems leading to clinical complications and even death. We aimed to review the development of the refeeding syndrome in a variety of situations and, from this and the literature, devise guidelines to prevent and treat the condition. We report seven cases illustrating different aspects of the refeeding syndrome and the measures used to treat it. The specific complications encountered, their physiological mechanisms, identification of patients at risk, and prevention and treatment are discussed. Each case developed one or more of the features of the refeeding syndrome including deficiencies and low plasma levels of potassium, phosphate, magnesium and thiamine combined with salt and water retention. These responded to specific interventions. In most cases, these abnormalities could have been anticipated and prevented. The main features of the refeeding syndrome are described with a protocol to anticipate, prevent and treat the condition in adults.

Alterations in QT dispersion in the surface electrocardiogram of female adolescents diagnosed with restricting-type anorexia nervosa

OBJECTIVE

QT dispersion (QTd), defined as the difference between the longest interval and the shortest interval in the 12-lead electrocardiogram (ECG), is a measure of myocardial repolarization inhomogeneity. We assessed QTd in malnourished anorexia nervosa (AN) inpatients and following weight restoration.

METHODS

QTd analysis, anthropometric evaluations, and laboratory tests were carried out in 30 malnourished female adolescent AN restricting-type (AN-R) inpatients and following weight restoration.

RESULTS

A significant increase was found in weight/height ratio and body mass index from malnourished stage to weight restoration, paralleled by a significant decrease in QTd (70+/-16 vs. 47+/-16 ms; P<.0001). No correlations were found between ECG indices and anthropometric and laboratory measures.

CONCLUSION

Elevated QTd in malnourished AN-R inpatients may indicate possible cardiac autonomic imbalance and/or myocardial damage, likely corrected following weight restoration.

Cardiovascular complications of eating disorders

Eating disorders (anorexia nervosa and bulimia) are associated with the highest mortality rate of any psychiatric disorder. Much of this mortality and morbidity stem from cardiovascular complications such as arrhythmia related to a prolonged QTc interval and/or electrolyte disorders, hypotension, and bradycardia. Structurally, the heart in patients with eating disorders is atrophic, which may relate to longstanding hypovolemia. These patients have low cardiac output and demonstrate increased peripheral vascular resistance despite the presence of hypotension. The treatment of eating disorders is incremental caloric feeding, which can have its own intrinsic cardiovascular risk (refeeding syndrome) manifested by arrhythmia, tachycardia, congestive heart failure, and sudden cardiac death. Patients will require close monitoring and slower refeedings to minimize the risk of these complications.

Low-K+ dependent QT prolongation and risk for ventricular arrhythmia in anorexia nervosa

BACKGROUND

QT prolongation and ventricular arrhythmia have been proposed as the mechanism for sudden death in anorexia nervosa. The prevalence and the cause of QT prolongation remain controversial.

OBJECTIVES

1) to evaluate ventricular repolarization in patients with anorexia; 2) to evaluate factors that may influence repolarization, with focus on electrolyte plasma levels and heart rate.

METHODS

29 patients with anorexia, age 22 +/- 5 years, BMI 13.8 +/- 1.5 were compared to 14 control female subjects, age 23 +/- 2 years, BMI 20.7 +/- 1.1. QT interval and QT dispersion were measured. Whenever a low potassium (<3.5 mEq/l) was found, ECG was repeated after normalization of serum levels. Heart rate and its variability in the frequency domain (LF/HF ratio) were evaluated.

RESULTS

Three patients (10.3%) showed severe hypokalemia (K(+) levels <2.0 mEq/l). In 2 patients, QT was severely prolonged (QT(c) 600 and 670 msec) and in one case associated with ventricular arrhythmia. QT(c) after K(+) plasma levels normalization was 392 +/- 25 in anorexia vs. 407 +/- 19 msec in controls, p = 0.08. Heart rate was 55 +/- 11 in anorexia vs. 66 +/- 8 beats per minute (BPM) in controls, p = 0.002. The LF/HF ratio was 1.79 +/- 1.35 in anorexia and 3.66 +/- 2.64 in controls, p = 0.006.

CONCLUSIONS

QT interval is usually normal in patients with anorexia. QT prolongation and ventricular arrhythmia may develop in the setting of severe hypokalemia, exposing patients to high risk of sudden cardiac event. Resting heart rate is lower in anorexia than in controls with the spectral indices of sympatho-vagal balance indicating a prevalence of vagal activity.

Acquired QT prolongation associated with esophagitis and acute weight loss: how to evaluate a prolonged QT interval

When the physician is confronted with a patient having significant QT prolongation, it is critical to determine whether the patient harbors a genetic defect and a transmissible form of long QT syndrome (LQTS) or whether the QT prolongation has an acquired cause. The distinction has profound ramifications for the type of care provided to the patient and family. We report the case of a previously healthy 14-year-old boy who presented with a 10-day history of painful swallowing, a 10-lb weight loss, and chest pain. A 12-lead electrocardiogram (ECG) showed marked QT prolongation. Endoscopy and culture identified a Herpes simplex esophageal ulcer. After treatment with acyclovir, the patient recovered completely. Three weeks after the resolution of his symptoms and recovery from his acute weight loss, a follow-up ECG showed complete normalization of the QT interval. This case illustrates yet another potential mechanism for acquired QT prolongation. We also provide a diagnostic algorithm for the careful evaluation of a prolonged QT interval.

Disorders of Fuel Metabolism: Medical Complications Associated with Starvation, Eating Disorders, Dietary Fads, and Supplements

Disorders of fuel metabolism as they relate to abnormal fuel intake,abnormal fuel expenditure, and dietary supplements are the focus of this article. The emergency physician should be aware of the medical complications that can occur as a result of starvation states,eating disorders, fad diets, hypermetabolic states, and ergogenic aids. Knowledge and understanding of the complications associated with these disorders will facilitate the diagnosis and management of patients who present to the emergency department with any of the disorders reviewed.

Cardiac findings in adolescents with anorexia nervosa at diagnosis and after weight restoration

The aim of this study was to compare heart abnormalities in a group of young women with anorexia nervosa at diagnosis and after weight restoration. A total of 40 young women with anorexia nervosa were evaluated, at baseline, (diagnosis) and follow-up (9 to 18 months later) and matched with 40 healthy women of the same age and of normal weight. QT interval was measured from surface electrocardiograms. QT dispersion was defined as the difference between maximum QT and minimum QT occurring in any of the 12 leads. Left ventricular end-diastolic diameter, left ventricular end-systolic diameter, left ventricular mass, left ventricular mass index, cardiac output, fractional shortening and fractional ejection, were measured by echocardiography. In anorexia nervosa patients, corrected QT interval and QT dispersion, significantly decreased from baseline to follow-up. Left ventricular end-diastolic dimension, left ventricular mass index, and cardiac output, in anorexia nervosa were significantly lower at diagnosis than at follow-up after weight restoration.

CONCLUSION

Adolescents with anorexia nervosa have significant functional and structural cardiac abnormalities; weight gain was associated with improvement. Appropriate attention should be paid to cardiac involvement.

Intrauterine growth retardation is a risk factor for cisapride-induced QT prolongation in preterm infants

BACKGROUND

Cisapride is a possible cause of potentially life threatening QT prolongation.

AIMS

We investigated these cardiac side effects in premature infants, mainly in relation to fetal growth.

PATIENTS

Forty six preterms (mean birth weight 1.350 g, mean post conceptional age 31 weeks) were studied. Thirty-one of them were appropriate for gestational age (AGA) and 15 were small for gestational age (SGA). Cisapride was randomly administered at a 0.3 mg/kg or 0.6 mg/kg daily dose. Fifty preterms (15 SGA/35 AGA) not treated with Cisapride were used as control group.

METHODS

A pre-treatment ECG was performed and the QT-corrected (Bazzet's formula) intervals were compared with the in-treatment values (normal values < or =440 mseconds). In the control group two different ECG were performed with a timing similar to the treated group (mean interval 5 days).

RESULTS AND CONCLUSIONS

No patients showed clinical evidence of drug toxicity. In the small for gestational age group, both baseline QTc (mean 397; range 370-420 ms) and in-treatment QTc (mean 410 range 360-500 ms) were significantly higher than those found in the appropriate for gestational age group (mean 386, range 360-420 ms; mean 396, range 370-420 ms, respectively). This difference was found also in the first ECG of the control group. Moreover the mean QTc lengthening during treatment was significantly higher in small for gestational age group than in the appropriate for gestational age group. Three infants showed a rise in the QTc interval above the value of 440 ms and all were SGA (p = 0.03). No significant correlation was found between birth weight or gestational age and the change in QTc values during Cisapride treatment in the appropriate for gestational age group. Intrauterine growth retardation is a major risk factor for Cisapride-induced QT prolongation in preterm infants.