Echocardiographic features of impaired left ventricular diastolic function in Chagas's heart disease.

Abstract

To study left ventricular diastolic function in Chagas's disease, simultaneous echocardiograms, phonocardiograms, and apexcardiograms were recorded in 20 asymptomatic patients with positive Chagas's serology and no signs of heart disease (group 1), 12 with Chagas's heart disease and symptoms of ventricular arrhythmia but no heart failure (group 2), 20 normal subjects (group 3), and 12 patients with left ventricular hypertrophy (group 4). The recordings were digitised to determine left ventricular isovolumic relaxation time and the rate and duration of left ventricular cavity dimension increase and wall thinning. In groups 1 and 2 (a) aortic valve closure (A2) and mitral valve opening were significantly delayed relative to minimum dimension and were associated with prolonged isovolumic relaxation, (b) left ventricular cavity size was abnormally increased during isovolumic relaxation and abnormally reduced during isovolumic contraction, and (c) peak rate of posterior wall thinning and dimension increase were significantly reduced and duration of posterior wall thinning was significantly prolonged; both of these abnormalities occurred at the onset of diastolic filling. These abnormalities were more pronounced in group 2 and were accompanied by an increase in the height of the apexcardiogram "a" wave, an indication of pronounced atrial systole secondary to end diastolic filling impairment due to reduced left ventricular distensibility. Group 4, which had an established pattern of diastolic abnormalities, showed changes similar to those in group 2; however, the delay in aortic valve closure (A2) and in mitral valve opening and the degree of dimension change were greater in the latter group. Thus early isovolumic relaxation and left ventricular abnormalities were pronounced in the patients with Chagas's heart disease and may precede systolic compromise, which may become apparent in later stages of the disease. The digitised method is valuable in the early detection of myocardial damage.

Capacidade funcional máxima e função diastólica em portadores de cardiomiopatia chagásica sem insuficiência cardíaca congestiva

“…Estudos ecocardiográficos anteriores da doença cardíaca assintomática com alterações eletrocardiográficas mostraram pacientes com contratilidade normal ou alterada 20 . Alguns autores encontraram disfunção diastólica significativa nestes grupos [21][22][23] . Estes achados levaram os autores a acreditar que as manifestações iniciais da cardiomiopatia chagásica são predominantemente secundárias a disfunção diastólica em vez de sistólica.…”

“…Os pacientes chagásicos apresentaram valores menores da onda E e da relação E/A quando comparados com o grupo controle, sugerindo que eles apresentam uma disfunção diastólica, como foi descrito previamente [21][22][23] . Como o grupo Chagas têm diâmetros e DD normais e padrão de relaxamento anormal em repouso, foi tentado encontrar alterações funcionais durante o exercício, denotando comprometimento da reserva cardíaca.…”

Avaliação de pacientes assintomáticos com forma crônica da doença de Chagas através da análise do eletrocardiograma dinâmico, ecocardiograma e do peptídeo natriurético tipo B

“…In chagasic patients, however, it ranges from 27.6% to 83%, according to the evaluation method employed and the clinical form of the disease 45 . Early studies on diastolic dysfunction in Chagas' disease through non-invasive methods used M-mode ECHO associated with phonocardiogram and apexcardiogram followed by two-dimensional echocardiogram coupled with Doppler flow studies and, finally, tissue Doppler.…”

Cellular and Cytokine Characterization of Vascular Inflammation in CBA/J Mice Chronically Infected with Trypanosoma cruzi

“…Concurrently, the vascular damage also gives rise to pathology in skeletal muscles in which an increased infiltrate of inflammatory cells is recorded ( [22] and our unpublished observations). The lymphocytic infiltration presented near the root of the aorta could explain the common delayed closure of the aortic valve in early chronic Chagas' disease patients [23]. Furthermore, the inflammation present in arteries may enhance the risk of thrombosis, accentuating cardiovascular disease and thereby increasing morbidity in individuals with Chagas' disease.…”