Assessment of myocardial perfusion with real-time myocardial contrast echocardiography: methodology and clinical applications.
J Nucl Cardiol
; 12(5): 582-90, 2005.
Article
em En
| MEDLINE
| ID: mdl-16171719
ABSTRACT
Real-time myocardial contrast perfusion imaging (RTMCI) with echocardiography is a promising technique for evaluation of patients with known or suspected coronary artery disease. The technique is based on the utilization of small (<10 mum) microbubbles, which are capable of crossing the pulmonary circulation after intravenous injection. Unlike radioactive isotopes, which are taken actively or diffuse passively in the myocytes, myocardial contrast agents remain extracellularly in the capillaries and present a measure of the myocardial capillary blood volume and microvascular integrity. RTMCI has been shown to be a safe and feasible method for the assessment of myocardial perfusion at rest and with pharmacologic stress. Recent studies have shown the value of RTMCI with dobutamine stress in improving overall and regional detection of coronary artery disease and detecting of abnormalities at submaximal stress, therefore improving sensitivity in patients who are unable to achieve the target heart rate. The advantages of the technique include the ability to assess perfusion at bedside in one setting, simultaneous assessment of myocardial function, shorter imaging time, no need for ionizing irradiation, immediate availability of the results, and the ability to determine the ischemic threshold. Recent studies have shown that RTMCI improves the prognostic utility of standard dobutamine stress in addition to wall motion analysis. Patients with normal perfusion had a better outcome than those with normal wall motion. The combination of abnormal wall motion and perfusion identified patients at greatest risk of death and nonfatal myocardial infarction. Perfusion abnormalities were also shown to predict short-term cardiac events in patients presenting to the emergency department with chest pain and no ST-segment elevation. Refinement of imaging techniques is expected to improve the specificity of RTMCI, particularly in differentiating true perfusion defects from artifacts. This review will discuss the physiologic basis, methodology, clinical utility, and limitations of RTMCI in the assessment of patients with known or suspected coronary artery disease.
Buscar no Google
Temas:
ECOS
/
Aspectos_gerais
Bases de dados:
MEDLINE
Assunto principal:
Doença da Artéria Coronariana
/
Ecocardiografia
/
Aumento da Imagem
/
Disfunção Ventricular Esquerda
Tipo de estudo:
Diagnostic_studies
/
Etiology_studies
/
Guideline
/
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
J Nucl Cardiol
Assunto da revista:
CARDIOLOGIA
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
Estados Unidos