Cardiac and autonomic evaluation in a pediatric population with human immunodeficiency virus

Biventricular diastolic function assessed by Doppler echocardiogram in children vertically infected with human immunodeficiency virus

OBJECTIVE

to determine, by Doppler-echocardiography, the frequency of cardiac diastolic dysfunction in asymptomatic and clinically stable pediatric patients with vertical infection by the human immunodeficiency virus (HIV), from the cardiovascular viewpoint.

METHODS

this was an observational, prospective, and cross-sectional study, performed at a regional referral clinic for patients with HIV, in a convenience sample of 94 individuals, assessing biventricular diastolic function by Doppler-echocardiography, and weight, blood hemoglobin, and percentage of lymphocytes T-CD4(+).

RESULTS

fifty patients had diastolic dysfunction. Left ventricular dysfunction occurred in 38.7%, and the predominant type of dysfunction was decreased myocardial compliance. Right ventricular dysfunction was observed in 29.4% of the sample, and abnormal relaxation was the most prevalent type. Simultaneous biventricular dysfunction occurred in 14.1% of the individuals. There was no association between dysfunction and the immune status.

CONCLUSIONS

diastolic dysfunction occurred, individually or simultaneously, with no association with immune status; decreased myocardial compliance was predominant in the left ventricle, and abnormal relaxation in the right ventricle.

Heart disease among children with HIV/AIDS attending the paediatric infectious disease clinic at Mulago Hospital

BACKGROUND

There are very few published studies of heart disease in HIV infected children living in sub-Saharan Africa, a region with more than 50% of the world's population of HIV infected patients.

OBJECTIVES

To determine the prevalence, and describe the type and clinical presentation of heart disease among children with HIV attending an ambulatory clinic.

METHODOLOGY

Two hundred and thirty (230) HIV infected children attending the Paediatric Infectious Disease Clinic at Mulago hospital were recruited by simple random sampling in a cross-sectional study. The children were evaluated clinically, and investigated by electrocardiography and echocardiography.

RESULTS

Thirty-two children (13.9%) had asymptomatic HIV disease, 156 (67.8%) had AIDS related complex while 42 (18.3%) had AIDS. Heart abnormalities were detected in 51% of the children (40.0% by echocardiography alone and 26.5% by electrocardiography alone). Heart abnormalities were most prevalent in children with AIDS (76.2%) and least prevalent in children with asymptomatic HIV disease (25.0%). The abnormalities included; Sinus tachycardia (21%), left ventricular systolic dysfunction (17%), right ventricular dilatation (14%), congenital heart disease (4.8%), dilated cardiomyopathy (3.0%), pericarditis (2.2%) and cor pulmonale (1.3%). Children with left ventricular systolic dysfunction significantly had easy fatigability, dyspnoea on exertion and tachypnoea. Other heart abnormalities presented with non-specific clinical features.

CONCLUSION

Heart abnormalities were common especially in children with symptomatic HIV disease and included sinus tachycardia, left ventricular systolic dysfunction and right ventricular dilatation. The detected heart abnormalities, except left ventricular systolic dysfunction, had non-specific clinical features.

Decreased peak arteriovenous oxygen difference during treadmill exercise testing in individuals infected with the human immunodeficiency virus

OBJECTIVE

To determine if arteriovenous oxygen difference was lower in asymptomatic individuals with human immunodeficiency virus (HIV) infection than in sedentary but otherwise healthy controls.

DESIGN

Quasi-experimental cross-sectional.

SETTING

Clinical exercise laboratory.

PARTICIPANTS

Fifteen subjects (10 men, 5 women) with HIV and 15 healthy gender- and activity level-matched controls (total N=30).

INTERVENTION

Participants performed an incremental maximal exercise treadmill test to exhaustion. Electrocardiogram, metabolic, and noninvasive cardiac output measurements were evaluated at rest and throughout the tests. Data were analyzed by using analysis of covariance.

MAIN OUTCOME MEASURES

Peak oxygen consumption (Vo(2)), cardiac output, stroke volume, and arteriovenous oxygen difference. The arteriovenous oxygen difference was determined indirectly using the Fick equation.

RESULTS

Peak VO(2) was significantly lower (P<.0005) in participants with HIV (24.6+/-1.2mL.kg(-1).min(-1)) compared with controls (32.0+/-1.2mL.kg(-1).min(-1)). There were no significant intergroup differences in cardiac output or stroke volume at peak exercise. Peak arteriovenous oxygen difference was significantly lower (P<.04) in those infected with HIV (10.8+/-0.5 volume %) than in controls (12.4+/-0.5 volume %).

CONCLUSION

The observed deficit in aerobic capacity in the participants with HIV appeared to be the result of a peripheral tissue oxygen extraction or utilization limitation. In addition to deconditioning, potential mechanisms for this significant attenuation may include HIV infection and inflammation, highly active antiretroviral therapy medication regimens, or a combination of these factors.

Clinical course of cardiomyopathy in HIV-infected patients with or without encephalopathy related to the myocardial expression of tumour necrosis factor-alpha and nitric oxide synthase

OBJECTIVE

To define whether the development of encephalopathy influences the clinical course of HIV-associated cardiomyopathy (HIV-DCM) in relation to the myocardial expression of tumour necrosis factor-alpha (TNF-alpha) and inducible nitric oxide synthase (iNOS).

DESIGN

Prospective study.

SETTING

University hospitals and AIDS centres.

METHODS

115 HIV-infected patients with echocardiographic diagnosis of HIV-associated cardiomyopathy (34 with encephalopathy and 81 without encephalopathy) were followed for a mean of 24 +/- 3.2 months. All patients underwent endomyocardial biopsy for determination of myocardial immunostaining intensity of TNF-alpha and iNOS. Cerebrospinal fluid (CSF) from patients with encephalopathy was examined for the presence of viruses. Patients underwent clinical examination every 3 months and echocardiographic examination every 6 months. The intensity of TNF-alpha and iNOS immunostaining was also evaluated on postmortem cerebral tissue of patients who died of congestive heart failure (CHF).

RESULTS

A greater impairment of echocardiographic parameters was observed in patients with HIV-associated cardiomyopathy after development of encephalopathy. These parameters tended to worsen progressively during the follow-up period and were inversely correlated with HIV-1 viral load, CD4 cell count, mini mental status score and the intensity of myocardial and cerebral TNF-alpha and iNOS staining. CSF specimens were available in 29 patients with encephalopathy. HIV-1 sequences were detected in CSF of all these patients with cytomegalovirus sequences in two. The mortality rate for CHF was greater among patients with encephalopathy (73% versus 12%).

CONCLUSIONS

The development of encephalopathy has an adverse effect on the clinical course of HIV-associated cardiomyopathy. In the relationship between cardiomyopathy and encephalopathy, the activation of iNOS by TNF-alpha may have a significant pathogenetic role in HIV disease.