The heart in kwashiorkor

Implementation and evaluation of a shock curriculum using simulation in Manila, Philippines: a prospective cohort study

BACKGROUND

Shock causes significant morbidity and mortality in children living in resource-limited settings. Simulation has been successfully used as an educational tool for medical professionals internationally. We sought to improve comfort and knowledge regarding shock recognition and fluid management by implementing a pediatric shock curriculum using simulation as an assessment for trainees in Manila, Philippines.

METHODS

We assessed a shock curriculum focused on patients with malnutrition in a prospective cohort study, using a written test and a videotaped simulation-based objective standardized clinical examination. Implementation occurred in March 2020 with 24 Filipino pediatric residents at a single institution in Manila. Outcomes included time to initiation of fluid resuscitation, improvement in confidence, knowledge on a written assessment, and performance in simulation. Results were compared pre- and post-intervention using Wilcoxon signed-rank test.

RESULTS

The time to initiation of fluids did not change between the baseline simulation (median [interquartile range] = 71.5 seconds [52-116.5]) and the final simulation (68 seconds [52.5-89]; P = 0.42). Confidence in identifying shock and malnutrition, managing hypovolemic shock, managing septic shock, and placing intraosseous access all increased (P < 0.01) post-intervention. Written test scores showed no improvement, but performance in simulation, measured using a checklist, improved from a total score of 10 [8.5-11] to 15 [13-16] (P < 0.01).

CONCLUSION

In our study of a simulation-based shock education program, we showed improvement in confidence and knowledge as measured by a resuscitation checklist. It is feasible to establish a successful simulation-based education program in a low-resource setting.

Cardiomyopathy in Children: Classification and Diagnosis: A Scientific Statement From the American Heart Association

In this scientific statement from the American Heart Association, experts in the field of cardiomyopathy (heart muscle disease) in children address 2 issues: the most current understanding of the causes of cardiomyopathy in children and the optimal approaches to diagnosis cardiomyopathy in children. Cardiomyopathies result in some of the worst pediatric cardiology outcomes; nearly 40% of children who present with symptomatic cardiomyopathy undergo a heart transplantation or die within the first 2 years after diagnosis. The percentage of children with cardiomyopathy who underwent a heart transplantation has not declined over the past 10 years, and cardiomyopathy remains the leading cause of transplantation for children >1 year of age. Studies from the National Heart, Lung, and Blood Institute-funded Pediatric Cardiomyopathy Registry have shown that causes are established in very few children with cardiomyopathy, yet genetic causes are likely to be present in most. The incidence of pediatric cardiomyopathy is ≈1 per 100 000 children. This is comparable to the incidence of such childhood cancers as lymphoma, Wilms tumor, and neuroblastoma. However, the published research and scientific conferences focused on pediatric cardiomyopathy are sparcer than for those cancers. The aim of the statement is to focus on the diagnosis and classification of cardiomyopathy. We anticipate that this report will help shape the future research priorities in this set of diseases to achieve earlier diagnosis, improved clinical outcomes, and better quality of life for these children and their families.

Assessment of Myocardial Function in Kenyan Children With Severe, Acute Malnutrition: The Cardiac Physiology in Malnutrition (CAPMAL) Study

Importance

Mortality among African children hospitalized with severe malnutrition remains high, with sudden, unexpected deaths leading to speculation about potential cardiac causes. Malnutrition is considered high risk for cardiac failure, but evidence is limited.

Objective

To investigate the role of cardiovascular dysfunction in African children with severe, acute malnutrition (SAM).

Design, Setting, and Participants

A prospective, matched case-control study, the Cardiac Physiology in Malnutrition (CAPMAL) study, of 88 children with SAM (exposed) vs 22 severity-matched patients without SAM (unexposed) was conducted between March 7, 2011, and February 20, 2012; data analysis was performed from October 1, 2012, to March 1, 2016.

Exposures

Echocardiographic and electrocardiographic (ECG) recordings (including 7-day Holter monitoring) at admission, day 7, and day 28.

Main Outcomes and Measures

Findings in children with (cases) and without (controls) SAM and in marasmus and kwashiorkor phenotypes were compared.

Results

Eighty-eight children (52 with marasmus and 36 with kwashiorkor) of the 418 admitted with SAM and 22 severity-matched controls were studied. A total of 63 children (57%) were boys; median age at admission was 19 months (range, 12-39 months). On admission, abnormalities more common in cases vs controls included severe hypokalemia (potassium <2.5 mEq/L) (18 of 81 [22%] vs 0%), hypoalbuminemia (albumin level <3.4 g/dL) (66 of 88 [75%] vs 4 of 22 [18%]), and hypothyroidism (free thyroxine level <0.70 ng/dL or thyrotropin level >4.2 mU/L) (18 of 74 [24%] vs 1 of 21 [5%]) and were associated with typical electrocardiographic changes (T-wave inversion: odds ratio, 7.3; 95% CI, 1.9-28.0; P = .001), which corrected as potassium levels improved. Fourteen children with SAM (16%) but no controls died. Myocardial mass was lower in cases on admission but not by day 7. Results of the Tei Index, a measure of global cardiac function, were within the reference range and similar in cases (median, 0.37; interquartile range [IQR], 0.26-0.45) and controls (median, 0.36; IQR, 0.28-0.42). Echocardiography detected no evidence of cardiac failure among children with SAM, including those receiving intravenous fluids to correct hypovolemia. Cardiac dysfunction was generally associated with comorbidity and typical of hypovolemia, with low cardiac index (median, 4.9 L/min/m2; IQR, 3.9-6.1 L/min/m2), high systemic vascular resistance index (median, 1333 dyne seconds/cm5/m2; IQR, 1133-1752 dyne seconds/cm5/m2), and with few differences between the marasmus and kwashiorkor manifestations of malnutrition. Seven-day continuous ECG Holter monitoring during the high-risk initial refeeding period demonstrated self-limiting significant ventricular arrhythmias in 33 of 55 cases (60%) and 6 of 18 controls (33%) (P = .049); none were temporally related to adverse events, including fatalities.

Conclusions and Relevance

There is little evidence that African children with SAM are at greater risk of cardiac dysfunction or clinically significant arrhythmias than those without SAM or that marasmus and kwashiorkor differed in cardiovascular profile. These findings should prompt a review of current guidelines.

The effects of malnutrition on cardiac function in African children

OBJECTIVE

Cardiac dysfunction may contribute to high mortality in severely malnourished children. Our objective was to assess the effect of malnutrition on cardiac function in hospitalised African children.

DESIGN

Prospective cross-sectional study.

SETTING

Public referral hospital in Blantyre, Malawi.

PATIENTS

We enrolled 272 stable, hospitalised children ages 6-59 months, with and without WHO-defined severe acute malnutrition.

MAIN OUTCOME MEASURES

Cardiac index, heart rate, mean arterial pressure, stroke volume index and systemic vascular resistance index were measured by the ultrasound cardiac output monitor (USCOM, New South Wales, Australia). We used linear regression with generalised estimating equations controlling for age, sex and anaemia.

RESULTS

Our primary outcome, cardiac index, was similar between those with and without severe malnutrition: difference=0.22 L/min/m(2) (95% CI -0.08 to 0.51). No difference was found in heart rate or stroke volume index. However, mean arterial pressure and systemic vascular resistance index were lower in children with severe malnutrition: difference=-8.6 mm Hg (95% CI -12.7 to -4.6) and difference=-200 dyne s/cm(5)/m(2) (95% CI -320 to -80), respectively.

CONCLUSIONS

In this largest study to date, we found no significant difference in cardiac function between hospitalised children with and without severe acute malnutrition. Further study is needed to determine if cardiac function is diminished in unstable malnourished children.

Cardiac Dysfunction in a Porcine Model of Pediatric Malnutrition

BACKGROUND

Half a million children die annually of severe acute malnutrition and cardiac dysfunction may contribute to the mortality. However, cardiac function remains poorly examined in cases of severe acute malnutrition.

OBJECTIVE

To determine malnutrition-induced echocardiographic disturbances and longitudinal changes in plasma pro-atrial natriuretic peptide and cardiac troponin-T in a pediatric porcine model.

METHODS AND RESULTS

Five-week old piglets (Duroc-x-Danish Landrace-x-Yorkshire) were fed a nutritionally inadequate maize-flour diet to induce malnutrition (MAIZE, n = 12) or a reference diet (AGE-REF, n = 12) for 7 weeks. Outcomes were compared to a weight-matched reference group (WEIGHT-REF, n = 8). Pro-atrial natriuretic peptide and cardiac troponin-T were measured weekly. Plasma pro-atrial natriuretic peptide decreased in both MAIZE and AGE-REF during the first 3 weeks but increased markedly in MAIZE relative to AGE-REF during week 5-7 (p ≤ 0.001). There was overall no difference in plasma cardiac troponin-T between groups. However, further analysis revealed that release of cardiac troponin-T in plasma was more frequent in AGE-REF compared with MAIZE (OR: 4.8; 95%CI: 1.2-19.7; p = 0.03). However, when release occurred, cardiac troponin-T concentration was 6.9-fold higher (95%CI: 3.0-15.9; p < 0.001) in MAIZE compared to AGE-REF. At week 7, the mean body weight in MAIZE was lower than AGE-REF (8.3 vs 32.4 kg, p < 0.001), whereas heart-weight relative to body-weight was similar across the three groups. The myocardial performance index was 86% higher in MAIZE vs AGE-REF (p < 0.001) and 27% higher in MAIZE vs WEIGHT-REF (p = 0.025).

CONCLUSIONS

Malnutrition associates with cardiac dysfunction in a pediatric porcine model by increased myocardial performance index and pro-atrial natriuretic peptide and it associates with cardiac injury by elevated cardiac troponin-T. Clinical studies are needed to see if the same applies for children suffering from malnutrition.

Fluid management of shock in severe malnutrition: what is the evidence for current guidelines and what lessons have been learned from clinical studies and trials in other pediatric populations?

Management of shock in children with severe malnutrition remains controversial. To date, the evidence supporting either benefit or harm of fluid resuscitation or rehydration is weak. This issue, however, is not unique to children with severe malnutrition; pediatric guidelines worldwide have a weak level of evidence and remain unsupported by appropriate clinical studies. In this review we give an overview of the current recommendations in other pediatric populations and appraise the strength of evidence supporting these. We summarize results from the only controlled trial ever undertaken, FEAST (Fluid Expansion As Supportive Therapy), which was conducted in resource-poor hospitals involving 3,141 African children with severe febrile illnesses and shock, including large subgroups with sepsis and malaria but excluding children with severe malnutrition. This high-quality trial provided robust evidence that fluid resuscitation increased the risk of death, leading to an excess mortality of 3 in every 100 children receiving fluid boluses, compared with controls receiving no boluses. These findings may have particular relevance to management of septic shock in children with severe malnutrition. However, they cannot be extrapolated to children with gastroenteritis, since this condition was not included in the trial. Current observational studies under way in East Africa may provide insights into myocardial and hemodynamic function in severe malnutrition, including responses to fluid challenge in those complicated by gastroenteritis. Such studies are an essential step for setting the research agenda regarding fluid management of shock in severe malnutrition.

Muscle morphology in infantile protein malnutrition

A study was made of the sartorius muscle in Jamaican infants dying of protein malnutrition. Total counts were made of muscle fibres and sub-sarcolemmal nuclei in transverse section and compared with controls.A striking pathology is found in severe cases. The muscle fibre is reduced to a size comparable with that of the foetus. Although there is a greatly increased concentration of cells, there is also degeneration and actual loss of fibres and of sub-sarcolemmal nuclei. The proportion of the area occupied by muscle bundles may be halved, and there is a marked relative increase in interstitial collagen. These changes profoundly affect the interpretation of the results of biochemical analysis.

Structural and functional affection of the heart in protein energy malnutrition patients on admission and after nutritional recovery

BACKGROUND AND OBJECTIVES

The pathogenesis of different malnutrition diseases was suggested to affect the heart. This study was designed to detect cardiac affection in protein energy malnutrition (PEM) patients, whether clinically or by electrocardiogram (ECG) and echocardiogram, and to assess the value of the cardiac marker troponin I in patients at risk of myocardial injury with special emphasis on the effect of nutritional rehabilitation.

PATIENTS AND METHODS

The present study was carried out on 30 PEM infants (16 nonedematous - 14 edematous) and 10 apparently healthy age and sex-matched infants acting as the control group. All studied infants were subjected to full history taking laying stress on dietetic history, thorough clinical and anthropometric measurements. Echocardiography and ECG were also performed. Laboratory investigations were performed including complete blood count, CRP, total proteins, albumin, liver and kidney functions as well as estimation of troponin-I in blood by immulite. Following initial evaluation, all malnourished infants were subjected to nutritional rehabilitation program for approximately 8 weeks, after which the patients were re-evaluated using the same preinterventional parameters.

RESULTS

The results of the present study demonstrated that electrical properties of myocardium assessed by ECG showed significant decrease of R wave and QTc interval in patients compared to controls with significant improvement after nutritional rehabilitation. Echocardigraphic changes showed that cardiac mass index was significantly lower in both groups of malnourished cases compared to the controls with significant increase after nutritional rehabilitation. The study showed that the parameters of left ventricular (LV) systolic function which are the ejection fraction, fractional shortening and velocity of circumferential fiber shortening were not significantly reduced in patients compared to the controls. The diastolic function also showed no significant difference in the E wave/A wave (e/a) ratio between patients and controls. However, the systolic time interval showed significantly higher LV pre-ejection index in patients in comparison to controls. Edematous and nonedematous cases did not show any significant differences in ECG and echocardigraphic data before or after nutritional rehabilitation. The hearts of two severely affected patients uniquely demonstrated marked decrease of LV end diastolic diameter (LEVDd) together with the detection of troponin-I in their sera.

CONCLUSION

We can conclude that malnutrition, regardless of its type, has a definite effect on cardiac volume, muscle mass, as well as the electrical properties of the myocardium. The systolic functions of the heart are affected more than the diastolic functions and this affection becomes manifest only in severe cases and may constitute a bad prognostic parameter thus necessitating more intense management and strict follow-up of such cases.

Postmortem cardiomegaly and echocardiographic measurements of left ventricular size and function in children infected with the human immunodeficiency virus. The Prospective P2C2 HIV Multicenter Study

BACKGROUND

Cardiomegaly, seen postmortem in over 50% of HIV-infected children, may occur in the absence of clinical or histopathologic cardiac disease. Premortem echocardiography has also demonstrated clinical and subclinical cardiac disease, including increased left ventricular mass (LVM) and functional abnormalities. No studies have compared these echocardiographic measures of heart size and function with postmortem findings in this population. We sought to determine the postmortem prevalence, clinicopathologic relationships and importance of cardiomegaly in HIV-infected children.

METHODS

We reviewed clinical and postmortem cardiac findings in 30 HIV-infected children who were part of the Prospective P(2)C(2) HIV Study. Postmortem heart weight was compared with clinical measures of heart size and function, with cardiac pathology and with clinical measures reflecting chronic effects of HIV disease.

RESULTS

Postmortem cardiomegaly (heart weight z score >/=2) was identified in 53% of the children. Children with cardiomegaly had increased LVM, increased heart rate, more frequent clinical chronic heart disease and a higher prevalence of postmortem pericardial effusions compared to children without cardiomegaly (P</=.05). The association with LV end-diastolic dimension (LVEDD) did not reach statistical significance (P=.08). No association was found with LV posterior wall thickness (LVPWT), CD4(+) T-cell counts, HIV-1 viral load, hemoglobin, encephalopathy, myocardial histology or myocardial organisms.

CONCLUSIONS

Postmortem cardiomegaly was associated with echocardiographic measures of increased LVM. The pathogenesis appears not to be related to chronic anemia, HIV viral load, the degree of immune suppression or encephalopathy. Autonomic dysregulation, reflected by chronically increased heart rate, may be of pathoetiologic significance.

Diarrhea reduces the rates of cardiac protein synthesis in myofibrillar protein fractions in rats in vivo

Although chronic diarrhea affects heart function and morphology, the pathogenic mechanisms are unknown. It was our hypothesis that diarrhea imposes metabolic stress to inhibit the synthesis of new contractile proteins. To test this hypothesis, we investigated the effects of lactose-induced diarrhea in rats. The groups were: 1) freely fed controls, 2) rats with lactose-induced diarrhea or 3) pair-fed rats. After 1 wk, hearts from the rats were subjected to subcellular fractionation techniques to isolate the major protein fractions, including myofibrillar proteins. The rates of protein synthesis were measured with concomitant assay of cardiac composition and plasma analytes. In comparison with the control group, diarrhea induced the following changes (P < 0.05): a decrease in heart weight, reduced RNA and mixed protein contents and a reduction in the fractional rate of mixed protein synthesis. There was a reduction in the content of all protein fractions. The fractional synthesis rate was reduced only for the myofibrillar fraction. Plasma insulin-like growth factor-I, but not corticosterone, was reduced. Plasma cholesterol and triglyceride concentrations were also reduced. In comparison with the pair-fed group, diarrhea induced the following changes (P < 0.05): a reduction in heart weight and fractional rate of mixed protein synthesis, reduced myofibrillar absolute synthesis rate and increased sarcoplasmic/myofibrillar fractional synthesis rate ratio. Plasma bicarbonate, triglyceride and urea concentrations were reduced, with an increase in albumin. Diarrhea impaired cardiac biochemistry, including a reduction in protein content and synthesis. A substantial proportion of these changes is due to anorexia, but the selective reduction in the synthesis of contractile proteins is a feature exclusive to the diarrhea group and may be due to reductions in plasma insulin-like growth factor-I.

Dietary protein or arginine deficiency impairs constitutive and inducible nitric oxide synthesis by young rats

Effects of dietary protein or arginine deficiency on constitutive and lipopolysaccharide (LPS)-induced nitric oxide (NO) synthesis were determined in young rats by quantifying urinary nitrate excretion. In Experiment 1, 30-d-old rats (n = 16) were divided randomly into two groups (n = 8/group) and pair-fed on the basis of body weight semipurified isocaloric diets containing 20 or 5% casein. In Experiment 2, 30-d-old rats (n = 24) were divided randomly into three groups (n = 8) and pair-fed on the basis of body weight purified isonitrogenous and isocaloric diets (composed of amino acids) containing 0.0, 0.3 or 1.0% L-arginine. In both experiments, daily collection of urine was initiated 10 d after the start of pair-feeding. On d 17 after the pair-feeding was initiated, LPS (1 mg/kg body wt) was injected intraperitoneally into rats, and urine was collected daily for an additional 7 d. In Experiments 3 and 4, activities of constitutive and inducible NO synthases were measured in macrophages and various tissues from protein- or arginine-deficient rats (n = 6). Body weight was lower in rats fed the 5% casein diet or the 0.0 and 0.3% arginine diets than in those fed 20% casein or 1% arginine, respectively. Dietary protein or arginine deficiency decreased serum concentrations of arginine and urinary nitrate excretion before and after LPS treatment, indicating impaired constitutive and inducible NO synthesis. Protein malnutrition reduced constitutive and inducible NO synthase activities in brain, heart, jejunum, lung, skeletal muscle and spleen, and inducible NO synthase activity in macrophages. Because NO is a mediator of the immune response and is the endothelium-dependent relaxing factor, impaired NO synthesis may help explain immunodeficiency and cardiovascular dysfunction in protein- or arginine-deficient subjects.

Cardiac disease in chronic uremia: clinical outcome and risk factors

Cardiac disease is common and is the major killer in end-stage renal disease (ESRD). Cardiac failure is a highly malignant condition in ESRD patients. Cardiac failure mediates most of the adverse prognostic impact of ischemic heart disease. Left ventricular (LV) abnormalities are already present at initiation of dialysis therapy in approximately 80% of patients. These abnormalities (ie, systolic dysfunction in approximately 15%, LV dilatation with preserved systolic function in 30%, concentric LV hypertrophy [LVH] in 40%) independently predict ischemic heart disease and cardiac failure, and are the largest baseline predictor of mortality after 2 years on dialysis therapy. The associations between classical risk factors (eg, hyperlipidemia, smoking, hypertension) and cardiac outcomes in ESRD are inconsistent. "Uremic" risk factors represent a nascent, but potentially important field. In our prospective 10-year study of 433 patients starting renal replacement therapy, we identified the following as major independent risk factors for cardiac disease: (1) hypertension (concentric LVH, LV dilatation, ischemic heart disease, cardiac failure, inverse relationship with mortality); (2) anemia (LV dilatation, cardiac failure, death); and (3) hypoalbuminemia (ischemic heart disease, cardiac failure, death). Transplantation dramatically improved LV abnormalities, suggesting that a uremic environment is cardiotoxic. Multiple risk factors act in concert to produce cardiac disease in ESRD; many of these are avoidable, suggesting that the enormous burden of disease can be reduced considerably.

Potassium supplementation in kwashiorkor

BACKGROUND

Kwashiorkor is an edimatous form of severe malnutrition and is the predominant form of childhood malnutrition in Malawi. Potassium depletion is common and contributes to the high mortality. The aim of this study was to determine if high potassium supplementation improves the outcome of kwashiorkor treatment.

METHODS

We performed a randomised, double-blind, placebo-controlled, clinical trial of high potassium supplementation in 99 children with kwashiorkor. Controls (n = 51) received a standard potassium intake of 4.7 mmol/kg/day. The intervention group (n = 48) received 7.7 mmol/kg/day. All cases (intervention and control groups) were treated in the hospital-based Nutrition Rehabilitation Center and received a standard treatment regime of mild feeds, mineral and vitamin supplements, and antibiotics.

RESULTS

There was no significant difference in length of hospitalization, or time for resolution of oedema between groups. The case-fatality rate was reduced by 33% in the high potassium intervention group (13/48) compared to controls (21/51). There was a significant reduction in late deaths (13 in controls vs 3 in intervention group; odds ratio 5.3, 95% confidence interval 1.2-31.0) but no difference in early deaths (0-5 days). The intervention group also had significantly fewer presumed septic episodes (3 vs 18, odds ratio 8.9, confidence interval 2.2-50.9), respiratory symptoms, and new skin ulcerations than controls.

CONCLUSIONS

The high potassium supplementation reduced mortality and significant morbidity in kwashiorkor. This may be due to improved myocardial and immune function from earlier repletion of intracellular potassium. We recommend that the standard potassium supplement for the initial phase of treatment of kwashiorkor be increased from 4 to 8 mmol/kg/day.

Outcome of protein-energy malnutrition in elderly medical patients

PURPOSE

To assess the impact of protein-energy malnutrition (PEM) on mortality and the long-term variations in the nutritional status of subjects admitted as emergency cases in a 9-month prospective follow-up study.

PATIENTS AND METHODS

The study comprised 205 patients without cancer aged 75 years (+/- 1). Malnourished subjects were identified as having at least three nutritional variables (which included weight index, triceps skinfold thickness, arm muscle circumference, serum albumin, and delayed cutaneous hypersensitivity reaction) below the reference range.

RESULTS

The mortality was 44% in the 41 malnourished patients and 18% in the 164 nonmalnourished subjects (P < 0.001). Among malnourished patients with congestive heart failure the mortality was 80%. Multivariate analysis revealed congestive heart failure, multiple organ disease, and PEM to be predictors of death. When the interaction between these disorders and PEM was considered, the prognostic relevance of PEM remained among the patients with cardiac congestion. Of the surviving subjects, 125 were reexamined after 9 months. At admission, more than half of the patients had displayed elevated levels of serum acid glycoprotein as evidence of an ongoing inflammation and subnormal recordings for serum albumin and delayed cutaneous hypersensitivity. At the reexamination, these variables had normalized in the well-nourished patients and in the 9 patients who had recovered from PEM, but remained unchanged in the 10 patients with persistent PEM. The latter patients were severely malnourished, commonly infected, and often hospitalized.

CONCLUSIONS

Protein-energy malnutrition in noncancer medical patients is associated with an excess mortality in those with congestive heart failure. Improvement of PEM is accompanied by a decline in inflammatory activity.

The electrocardiographic changes in kwashiorkor

An electrocardiogram (ECG), serum electrolytes, serum albumin, haematocrit and cardiothoracic ratio were recorded in 90 Nigerian children with kwashiorkor and 90 age- and sex-matched controls. The ECG abnormalities observed among the study group included sinus tachycardia (91%), low QRS amplitude (100%) and prolonged QTc intervals (17%). Other ECG abnormalities noted were short QTc intervals (three children), prolonged PR intervals (four children) and right axis deviation (two children). The mean serum sodium, potassium, calcium, albumin, haematocrit and cardiothoracic ratio were significantly lower in children with kwashiorkor than in the controls (p < 0.001). The correlation between the QRS amplitude and serum potassium and calcium was poor (p > 0.05). Also, there was poor correlation between heart rate and haematocrit (p > 0.05) and between QTc intervals and serum calcium and potassium (p > 0.05). However, the correlation between the QRS amplitude and cardiothoracic ratio was good (r = 0.91, p < 0.001). These findings suggest that the ECG changes in kwashiorkor are due to myocardial atrophy.

Left ventricular mass and function in children with severe protein energy malnutrition

We studied 25 children, aged 1-5 years (mean 2.65 +/- 0.8 years) with severe protein energy malnutrition, and compared their left ventricular mass and function to those of 26 healthy, age- and sex-matched normal children. The mean left ventricular mass in the patients was lower than that in the controls (25.75 +/- 8.09 g vs. 32.44 +/- 11.64 g; P less than 0.05, C.I. 2.08 to 11.30). However, left ventricular mass (g)/kg body weight was significantly increased in the patients (4.44 +/- 1.45 vs. 2.42 +/- 0.87; P less than 0.001, C.I. 1.28 to 2.76) suggesting relative cardiac "sparing". The systolic function indices like ejection fraction, percentage fractional shortening, and velocity of circumferential fiber shortening were not significantly different in the patients and in the normal children. The left ventricular end-diastolic volume, stroke volume and cardiac output were reduced in proportion to decrease in body size in the patients, so that the cardiac index was not reduced but slightly increased in the patients. (5.95 +/- 1.9 l/min/m2 in patients, 4.97 +/- 1.4 l/min/m2 in controls; P less than 0.05, C.I. 0.04 to 1.92). There was no significant difference in any of these parameters of left ventricular function or mass in patients with marasmus, as compared to those of patients with marasmic kwashiorkor. Amongst the 25 patients, however, 5 patients (20%) had an ejection fraction of less than 50%. Compared to the other 20 patients, these 5 patients had lower left ventricular mass (18.4 +/- 4.3 g vs. 27.5 +/- 7.8 g, P less than 0.05 C.I. 1.63 to 16.75), lower left ventricular mass (g)/kg body weight and a worse prognosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of kwashiorkor on the cardiovascular system

In kwashiorkor the heart is clinically and radiologically small. This study utilises echocardiography, a tool not previously used in this disease, to show that this is due to decreased muscle mass.

Biochemical consequences of protein depletion in the rabbit heart

We showed previously that cardiac function was depressed in rabbits subjected to 6 weeks of protein depletion and was restored after 4 weeks of protein refeeding. To identify nutritional or metabolic factors that underlie cardiac dysfunction, we assessed the nutritional status and myocardial content of energy-providing substrates in three groups of rabbits: group I served as control; group II was fed a protein-free diet; and group III was fed a protein-free diet and then repleted. Animal weights were 2.73 +/- 0.22 kg in group I, 1.92 +/- 0.28 kg in group II, and 2.78 +/- 0.12 kg in group III. Serum albumin concentrations decreased from 3.70 +/- 0.12 g/dl in group I to 2.81 +/- 0.10 g/dl in group II, and returned to normal (3.71 +/- 0.11 g/dl) in group III. The heart weights; myocardial contents of water, nitrogen (N), total fat, and glycogen; skeletal muscle N concentrations; and liver N contents were measured. Protein depletion produced a reduction in total cardiac mass due to decreased nitrogen and glycogen contents, but there was an increased fat content. Comparison with other organs suggests that cardiac muscle plays a role in energy homeostasis, undergoing glycogenolysis and proteolysis similar to those of liver and skeletal muscle. Protein repletion restored normal mass of the heart, but not of the liver. We conclude that adequate nutrition may be important in maintaining cardiac function.

Ultrastructural changes and enzyme activities for energy production in hearts concomitant with tumor-associated malnutrition

Morphometric data on left ventricular papillary muscle structures have been determined in tumor-induced malnutrition and related to the maximum activities of key enzymes for energy production in the whole myocardium. Adult, nongrowing mice with a syngeneic sarcoma were used to represent a condition of cancer associated host tissue wasting. Hearts from mice 11 days after tumor implantation showed atrophy and a significantly reduced amount of myofibrillar, soluble, and collagen proteins than hearts from control animals. The cross-sectional area of myocardial cells was 33% smaller in tumor-bearing mice (p less than 0.025), but the total number of capillaries and the residual interstitial volume were similar in the two groups. The total number of subcellular structures per cell, such as mitochondria, myofibrils, and myosin filaments per myofiber, were significantly lower in the tumor-bearing animals (p less than 0.025). Conversely, the proportion of myofibrils was higher (p less than 0.05) in tumor-bearing animals while the proportion of mitochondria was lower. Maximum activities (Vmax) of selected regulatory key enzymes for energy production (glycogenolytic, glycolytic, and mitochondrial) were not significantly altered in hearts from tumor-bearing mice. The results support the conclusion that myocardial functional capacity is better preserved than overall structural components would imply in tumor-host associated malnutrition, which is probably secondary to deprived food intake. Teleologically, this may be a means by which functional deterioration of the heart is minimized during the induction of malnutrition.

Malnutrition and the heart

Earlier concepts that the heart is spared in malnutrition have been shown to be incorrect. Inadequate intake of protein and energy results in proportional loss of skeletal and myocardial muscle. As myocardial mass decreases, so does the ability to generate cardiac output; however, various compensatory factors come into play. Nutritional supplementation for malnourished patients reverses the compensatory factors and may increase the short-term potential for heart failure. Severe cardiac debility results in poor nutrition, which may in turn produce unsuspected but clinically significant myocardial atrophy. Nutritional support may play a role in improving cardiac function in selected patients with cardiac cachexia who are being prepared for cardiac surgery and in patients with rapid weight loss who are at risk for sudden death due to arrhythmias. Malnutrition is common in hospitalized patients, and many patients in hospital now receive nutritional supplementation; both facts have important cardiac implications.

Effects of reduced left ventricular mass on chamber architecture, load, and function: a study of anorexia nervosa

We investigated the effects of reduction in left ventricular mass on cavity geometry, afterload, pump function, and exercise performance in 17 patients with anorexia nervosa and in 10 age-and sex-matched normal subjects. Left ventricular mass index determined by two-dimensional echo-cardiography was significantly lower than that in normal subjects (53 +/- 15 vs 79 +/- 18 g/m2; p less than .005). Left ventricular end-diastolic and end-systolic volume indexes were also reduced in patients with anorexia nervosa compared with normal subjects (49 +/- 11 vs 65 +/- 17 ml/m2, p less than .005; 14 +/- 5 vs 19 +/- 4 ml/m2, p less than .025). In spite of the reductions in left ventricular mass and volume indexes, left ventricular chamber architecture described as h/R ratio, mass to volume ratio, and short/long left ventricular axis ratio were normal. Left ventricular afterload assessed as end-systolic meridional and circumferential wall stress was normal (59 +/- 18 vs 79 +/- 19 dyne/cm2 X 10(3) and 170 +/- 26 vs 167 +/- 23 dyne/cm2 X 10(3)). Ejection fraction, percent fractional shortening, and the relationship between end-systolic wall stress and ejection fraction were all within normal limits. In seven patients restudied after a 15% to 20% weight gain, left ventricular mass and volume indexes increased significantly but end-systolic wall stress and ejection fraction did not change. Ten patients with anorexia nervosa and resting heart rates and systolic blood pressures significantly lower than control values underwent treadmill testing. Exercise duration, peak heart rate, peak systolic blood pressure, and peak oxygen consumption in these patients were all significantly lower than normal. The hypotensive effect of fasting resulted in an initial decrease in afterload, which was the stimulus for reduction in left ventricular mass. The left ventricular remodeling associated with the mass reduction occurred in such a way that (1) orthogonal, meridional, and circumferential wall stresses were normalized, (2) normal chamber shape and architecture were maintained, and (3) chamber function and stress-shortening relationships were preserved. Thus down-regulation of left ventricular mass per se, like up-regulation of left ventricular mass, is not associated with abnormal left ventricular function.

Infections and dilated cardiomyopathy in Nigeria

The relationship of infection to dilated cardiomyopathy is reviewed on the basis of 200 patients seen at University College Hospital, Ibadan. Evidence of infection with Toxoplasma and Coxsackie B viruses is presented. Clinically detectable myocarditis is rare in children, and the preponderance of dilated cardiomyopathy is in patients above the age of 30 years, possibly because there is a long latent period between the initial infection and the development of frank cardiomyopathy. This paper concluded that infections are probably the most important cause of dilated cardiomyopathy in Nigeria.

Altered exercise performance and abnormal sympathetic responses to exercise in patients with anorexia nervosa

We evaluated the cardiovascular and sympathetic responses to exercise in patients with anorexia nervosa to determine whether their bradycardia results from a high level of physical fitness. Twenty adolescent patients with anorexia nervosa underwent maximal exercise tests, and the results were compared with those in 15 age-matched adolescent girls. In the patients with anorexia, maximal values were heart rate 174 +/- 2.8 bpm, systolic blood pressure 127 +/- 3.4 mm Hg, oxygen consumption 31 +/- 1.1 ml/kg/min, and plasma norepinephrine concentration 1581 +/- 238 pg/ml (n = 16). In the controls, corresponding values were significantly higher (P less than 0.025): heart rate 193 +/- 2.1 bpm, systolic blood pressure 163 +/- 4.4 mm Hg, oxygen consumption 39.3 +/- 1.6 ml/kg/min, and plasma norepinephrine 2695 +/- 413 (n = 10). Anaerobic threshold occurred at the same percent of maximal work in patients and controls. Results of exercise ECGs in all controls were normal, but five patients with anorexia nervosa developed significant ST segment depression. Thus, in patients with anorexia nervosa there is abnormal working capacity and cardiovascular responses to exercise and abnormal sympathetic responses to the stimulus of exercise, and a myocardial abnormality manifested as ST segment depression during exercise in some.

Myocardial inotropic responses and adrenoceptors in protein-deficient rats

Inotropic effects of isoprenaline, phenylephrine and calcium were studied in left atria of 5 weeks old rats fed a low (5%) or a normal (21%) protein diet for 3 weeks. Rats maintained on a low (5%) protein diet consume about half the amount of food eaten by the same rats maintained on a normal (21%) protein diet and thus suffer from protein-calorie malnutrition (PCM). Body weight did not increase in PCM, but heart weight adjusted to body weight was slightly increased compared to normal rats. Atrial resting tension and peak developed tension in response to isoprenaline, phenylephrine or calcium were not diminished by PCM. The number of alpha and beta-adrenoceptors and the receptor affinity in ventricular membranes were not reduced by PCM.

Ultrastructural changes in nutritional cardiomyopathy of protein-calorie malnourished rats

In this investigation, the ultrastructural features of the nutritional cardiomyopathy of protein-calorie-malnourished rats were examined. Protein-calorie malnutrition was induced in young rats by feeding them a low-protein diet (4% protein) for 6 weeks. Control animals were fed a high-protein diet (16% protein). The deficient rats showed severe restriction of body-weight gain, fatty liver and hypoproteinaemia. The results of the present study clearly demonstrated that the experimentally induced protein-calorie malnutrition brings about striking morphological changes in the heart of the rat. On light microscopy hyalinization an vacuolization of muscle fibres, loss of cross striations and myofibrils, small foci of necrosis, interstitial fibrosis and mononuclear-cell infiltration could be detected. The ultrastructural lesions were characterized by myofibrillar degeneration, contraction-band formation, dilatation of sarcoplasmic reticulum, mitochondrial swelling, dehiscence of intercalated discs, and widened interstitial spaces, especially around vessels, due to oedema fluid and cellular infiltration by mononuclear cells an activated fibroblasts with collagen fibres and microfibrils. In addition, an increase in relative heart weight was also observed. The potential role of catecholamines in the pathogenesis of this cardiomyopathy is discussed.

Effect of protein-calorie malnutrition on catecholamine levels and weight of heart in rats

Catecholamine levels and weight of heart were studied in rats subjected to protein-calorie malnutrition and after a period of nutritional rehabilitation. Rats given a protein deficient diet (4% protein) for periods of 6 and 12 weeks showed a severe restriction of body weight gain. Nevertheless, even though the measured heart weight of deficient rats was significantly lower than the respective controls (16% protein), the deficient rats incurred "real" cardiac enlargement since the mean heart weight of the equal body weight controls was significantly different from that of the deficient animals. The mean heart weight of rats fed a high-protein diet for 6 weeks thereupon a 6-week period of protein deprivation was still less than that of controls, and the heart ratio was still greater than that of controls. However, the heart weight of rehabilitated rats was not significantly different from that of equal body weight controls. Serum protein and albumin levels in dificient rats were significantly decreased in comparison to rats fed a high-protein diet. While the serum protein levels of rehabilitated rats were lower than those of controls, the albumin levels were not different. The protein-calorie malnourished rats, which received a low-protein diet for 6 and 12 weeks, showed a significant increase in myocardium noradrenaline concentration. After a period of nutritional rehabilitation this change did not persist. These catecholaminergic alterations in heart may be responsible, at least in part, for the different cardiac abnormalities described as a result of protein-calorie dietary deficiency. It may also explain the "real" cardiac enlargement observed in deficient rats, according to the hypothesis that noradrenaline may be the ultimate myocardial hypertrophy hormone.

Noradrenaline levels and morphologic alterations of myocardium in experimental protein-calorie malnutrition

Experimental protein-calorie malnutrition was produced in rats by giving them a low-protein diet for 6 weeks. Control animals were fed a high-protein diet. The deficient rats showed severe restriction of body weight gain, fatty liver and hypoproteinaemia. In addition the present study demonstrates that the experimentally induced protein-calorie malnutrition brings about marked pathological changes and increased catecholamine levels in the hearts of rats. Based on this demonstration, and considering the synchronism of morphological and biochemical data, we postulate that the nutritional stress to the heart raises the myocardium noradrenaline concentration and the continued exposure to high levels of catecholamines may play a role in the development of cardiac changes in protein-energy malnutrition.

Conducting tissue of the heart in kwashiorkor

Images