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1.
J Am Soc Echocardiogr ; 14(10): 959-69, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11593200

RESUMO

The goals of this study were to evaluate possible normal age-related changes in regional myocardial relaxation as detected by color Doppler myocardial imaging (CDMI) velocities and to compare the extent of any such changes with age-induced changes in global diastolic function. In 80 healthy subjects (aged 21 to 72 years, equally subdivided by decades) the mitral flow velocities in early diastole (E) and atrial contraction (A) were recorded as were the velocities of left ventricular (LV) motion of early (EDV) and late diastole (LDV) in the 16 standard LV segments, and their ratios were calculated. In healthy persons younger than 40 years, all segments showed an EDV/LDV ratio > 1, whereas in healthy persons aged 40 years or older the mean EDV of all segments decreased, and the mean LDV increased, resulting in a significant decrease of the mean EDV/LDV ratio with age. Values of EDV/LDV ratios were higher than E/A ratios (P <.0001), but their changes with age correlated well with each other (r = 0.805). With increasing age, an EDV/LDV ratio <1 was observed more often in basal segments (P <.001, compared with mid and apical segments) and less often in segments of anteroseptal and posterior walls viewed from the parasternal window. The presence of >50% segments with an EDV/LDV ratio <1 was associated with an E/A ratio <1. Regional diastolic function indexes as evaluated by CDMI changed with increasing age in a heterogeneous way and influenced global diastolic function parameters.


Assuntos
Envelhecimento/fisiologia , Pressão Sanguínea/fisiologia , Ecocardiografia Doppler em Cores , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Diástole , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Projetos de Pesquisa
2.
J Am Soc Echocardiogr ; 11(7): 683-92, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9692525

RESUMO

A new color Doppler myocardial imaging (CDMI) system with high spatial and temporal resolution and novel postprocessing modalities has been developed that could allow quantifiable stress echocardiography. The purpose of this study was to determine whether regional myocardial systolic velocities could be accurately and reproducibly measured both at rest and during bicycle ergometry by using CDMI. Thirty normal subjects were examined with CDMI at rest, and peak mean systolic myocardial velocities (MSV) were measured for 34 predetermined left ventricular myocardial segments. Interobserver variability and intraobserver variability were established for all segments. Submaximal bicycle ergometry was performed in 20 normal subjects by using standardized weight-related increases in workload. MSV were measured at each step of exercise for 16 left ventricular stress echo segments. At rest, a base-apex gradient in regional MSV was recorded with highest longitudinal shortening velocities at the base. A similar pattern was noted for circumferential shortening MSV. Measurements were predictable and highly reproducible with low interobserver and intraobserver variability for 26 of 34 segments. Reproducibility was poor for basal anteroseptal segments in all views and mid anterior, anteroseptal, and septal segments in the short-axis views. During exercise, mid and basal segments of all walls showed a significant increase of MSV between each workload step and for apical segments between alternate steps. The resting base-apex velocity gradient observed at rest remained in all walls throughout ergometry. Thus a CDMI system with improved spatial and temporal resolution and postprocessing analysis modalities provided reproducible and accurate quantification of segmental left ventricular circumferential and longitudinal contraction both at rest and during exercise.


Assuntos
Ecocardiografia Doppler em Cores/métodos , Sístole/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Teste de Esforço , Humanos , Pessoa de Meia-Idade , Modelos Cardiovasculares , Variações Dependentes do Observador , Reprodutibilidade dos Testes
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