ABSTRACT
Objectives: Hypertension (HTN) is an inherited disorder and these patients manifest with cardiac autonomic dysfunction (CAD). The present study intends to assess the presence of pre HTN, clinical and subclinical CAD in adolescents with a family history of HTN, and to obtain its correlation with anthropometric values. Materials and Methods: After obtaining ethical clearance and informed consent, three groups containing 50 subjects each, of age 17–19 years were included in the study. (Group-I: Normotensives without a family history of HTN; Group-II: Normotensives with a family history of HTN and Group-III: prehypertensives). CAD was done by performing (1) resting tachycardia, (2) loss of sinus arrhythmia, and (3) heart rate response to the Valsalva manoeuvre. If any two of them are positive then the presence of CAD was confirmed. Results: Height, weight, BMI, SBP and DBP was significantly higher in group 3 (prehypertensives). Confirmed CAD findings was seen in 36% of group 2 and 46% of group 3 participants. Of the anthropometric parameters, a significant positive correlation was seen between weight and SBP, DBP and CAD parameters, and height with SBP and DBP. Conclusion: Clinical and subclinical CAD exists in adolescents with risk factors for HTN including heredity, obesity, and pre-HTN values. These risk factors show multiplicative effects for disease genesis and indicate high sympathetic and low parasympathetic drives. Extra care should be taken to curb the onset of clinical HTN and CAD in these young adults. Additional work needs to be done on pathophysiological mechanisms for the same.
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Background: Cardiovascular autonomic neuropathy (CAN) is a distinguished disorder associated with diabetes mellitus and metabolic syndrome. The pathogenesis of CAN in patients with metabolic syndrome still remains unclear. This study was undertaken to assess the prevalence of cardiac autonomic dysfunction in patients with metabolic syndrome and to correlate different parameters of metabolic syndrome with cardiac autonomic dysfunction.Methods: In this cross-sectional observational study, total 100 consecutive cases meeting the inclusion criteria and attending the Department of Medicine in Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi were enrolled. 50 subjects who satisfied the IDF criteria of metabolic syndrome were taken as cases and remaining 50 subjects (age and gender matched) who did not satisfy the IDF criteria were taken as controls. Comparison of categorical variables was made using chi-square or Fisher’s exact test. P-value <0.05 was considered as statistically significant.Results: Majority of study population (i.e., 42%) belonged to the age group of 41-50 years. Overall prevalence of cardiac autonomic dysfunction (CAD) was 25%. Prevalence of CAD among cases and controls was 38% and 12%, respectively. Overall distribution of various parameters like waist circumference, fasting blood glucose, blood pressure, HDL-C and serum triglycerides was assessed in all subjects with respect to CAD. Statistically significant association of these parameters was seen with CAD (p-value ≤0.01).Conclusions: In this study, strong association was found between CAD and central obesity, impaired fasting glucose, high blood pressure and dyslipidemia. Thus, the metabolic disorders are good predictors of CAD.
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INTRODUCTION: Exclusive or associated lesions in various structures of the autonomic nervous system occur in the chronic forms of Chagas disease. In the indeterminate form, the lesions are absent or mild, whereas in the exclusive or combined heart and digestive disease forms, they are often more pronounced. Depending on their severity these lesions can result mainly in cardiac parasympathetic dysfunction but also in sympathetic dysfunction of variable degrees. Despite the key autonomic effect on cardiovascular functioning, the pathophysiological and clinical significance of the cardiac autonomic dysfunction in Chagas disease remains unknown. METHODS: Review of data on the cardiac autonomic dysfunction in Chagas disease and their potential consequences, and considerations supporting the possible relationship between this disturbance and general or cardiovascular clinical and functional adverse outcomes. RESULTS: We hypothesise that possible consequences that cardiac dysautonomia might variably occasion or predispose in Chagas disease include: transient or sustained arrhythmias, sudden cardiac death, adverse overall and cardiovascular prognosis with enhanced morbidity and mortality, an inability of the cardiovascular system to adjust to functional demands and/or respond to internal or external stimuli by adjusting heart rate and other hemodynamic variables, and immunomodulatory and cognitive disturbances. CONCLUSIONS: Impaired cardiac autonomic modulation in Chagas disease might not be a mere epiphenomenon without significance. Indirect evidences point for a likely important role of this alteration as a primary predisposing or triggering cause or mediator favouring the development of subtle or evident secondary cardiovascular functional disturbances and clinical consequences, and influencing adverse outcomes.
INTRODUÇÃO: Lesões isoladas ou combinadas de várias estruturas do sistema nervoso autônomo ocorrem nas formas crônicas da doença de Chagas. Na forma indeterminada, as lesões são discretas e podem estar até ausentes, enquanto nas formas cardíaca e digestória exclusivas ou combinadas elas são comumente mais pronunciadas. Na dependência da sua maior ou menor severidade, estas lesões podem resultar em variáveis graus de disfunção parassimpática e/ou simpática, principalmente a primeira. Apesar da crítica influência autonômica sobre o funcionamento cardiovascular, o significado fisiopatológico e clínico, notadamente em longo prazo, da disfunção autonômica cardíaca permanece desconhecido na doença de Chagas. MÉTODOS: Revisão sobre a disfunção autonômica cardíaca na doença de Chagas e suas potenciais consequências, como base para considerações acerca da possível relação entre este distúrbio e desfechos clínicos e funcionais globais e cardiovasculares desfavoráveis. RESULTADOS: Os potenciais desfechos que a disautonomia cardíaca pode variavelmente determinar ou predispor na doença de Chagas incluem: arritmias transitórias ou sustentadas, morte súbita, mal prognóstico global e cardiovascular, morbi-mortalidade aumentada, deficiente adaptação cardiovascular a demandas funcionais e/ou em resposta a estímulos internos e externos por meio de ajustes da frequência cardíaca e outras variáveis hemodinâmicas, e distúrbios imunomoduladores e psico-funcionais. CONCLUSÕES: A alteração da modulação autonômica cardíaca na doença de Chagas pode não representar mero epifenômeno sem significado. Evidências indiretas sugerem papel importante desta alteração como fator predisponente ou determinante primário para o desenvolvimento secundário de distúrbios funcionais manifestos ou não e consequências clínicas cardiovasculares, e para a ocorrência de desfechos desfavoráveis.