[Assessment of right ventricular function using contrast echocardiography in patients with myocardial infarction]. / Valoración de la función ventricular derecha mediante ecocardiografía de contraste en pacientes con infarto agudo de miocardio.

OBJECTIVE: To evaluate right ventricular size, motility, and ejection fraction (RVEF) by contrast echocardiography. METHODS: We studied consecutive patients admitted to the coronary intensive care unit with acute inferior myocardial infarction, without prior infarction and with or without right ventricle involvement, according to accepted electrocardiographic findings. Polygelin, 3.5% solution, was used for contrast echocardiography. The reference standard was equilibrium radionuclide angiography. RESULTS: We studied 44 patients using contrast echocardiography, average patient age 60.8 +/- 10.6 years, 38 men and 6 women. Abnormal right ventricular size (more than 25 mm) yielded a sensitivity of 79%, specificity of 87%, positive and negative predictive values of 92 and 68%, respectively, and a likelihood ratio of 6. Abnormal right ventricular motility had a sensitivity of 70%, specificity of 94%, positive and negative predictive values of 95 and 67%, respectively, and a likelihood ratio of 11.6. Right ventricular ejection fraction < 30% with contrast echocardiography had a sensitivity of 69%, specificity of 97%, positive and negative predictive values of 90 and 88% respectively, and a likelihood ratio of 6.9. CONCLUSION: In patients with acute inferior myocardial infarction, contrast echocardiography with the area-length method is a valid and reproducible technique for evaluating right ventricular ejection fraction, which is easy to perform and can be done at the patient's bedside.

Angiografía por substracción digital: experiencia inicial en México / Angiography by digital substraction: initial experience in México

La angiografia por substracción digital es una nueva técnica radiológica que utiliza una computadora de alta velocidad para procesar las imágenes, convertirlas en valores digitales y resaltar la información subliminal; así mismo elimina estructuras sin interés en la imagen fluoroscópica. En este artículo se informan la experiencia inicial en México y las aplicaciones clínicas del sistema digital de imágens durante los primeros 15 meses de estudio en el Hospital de Cardiología y Neumología del IMSS. El equipo consta de un sistema computarizado integrado a un aparato radiológico de una sala de hemodinamia para el procesado, la manipulación y la exposición de los datos o imágenes. La administración endovenosa de material de contraste con esta técnica produce angiografías adecuadas de corazón y arterias carótidas, torácicas, abdominale y femorales, y substituye a la angiografía arterial ordinaria en varias situaciones clínicas. Este método no es selectivo; sin embargo, ofrece menor riesgo, es más rápido y se puede realizar en pacientes externos con reducción de costos y molestias para el enfermo. El procedimiento endovenoso no es selectivo pero su utilidad se extiende a los procedimientos intrarteriales

The value of electrocardiographic R-wave changes in exercise testing: Preexercise versus postexercise measurements.

To determine the usefulness of R-wave amplitude changes during exercise testing for the diagnosis of coronary artery disease (CAD) and to understand the discrepancies that have been described in the literature regarding their value, we studied two groups of patients by means of electrocardiographic (EKG) treadmill testing and coronary arteriography. Group I was composed of 149 patients who were studied prospectively. The specificity of R-wave changes measured from preexercise to immediately postexercise (SRV(5)) was 81%, but that of R-wave changes measured from preexercise to peak exercise (URV(5)) was 46%. A group of 156 patients (Group II) evaluated retrospectively showed a high specificity for the SRV(5) (84%) and poor specificity for the URV(5) (39%). The sensitivity of the SRV(5) was 38% in Group I and 42% in Group II. Therefore, if measured during the immediate postexercise period and not at peak exercise, changes in R-wave amplitude may be of value in the diagnosis of coronary artery disease by electrocardiographic exercise testing.