B-type natriuretic peptide and Tissue Doppler imaging in the diagnosis and prognosis of congestive heart failure

Tissue Doppler (TD) imaging is a novel echocardiographic technique that directly measures myocardial velocities. Diastolic TD values reflect myocardial relaxation, and in combination with conventional Doppler measurements, ratios (E/Ea: transmitral early diastolic velocity/mitral annular early diastolic velocity) have been developed to noninvasively estimate left ventricular (LV) filling pressures. These TD-derived ratios have been helpful in diagnosing elevated LV filling pressures, clinical congestive heart failure (CHF), and the prognosis of patients with cardiac disease and CHF. B-type natriuretic peptide is secreted by the ventricle in the presence of myocyte stretch, and has been correlated to LV filling pressures and cardiac morphological abnormalities (depressed ejection fraction, RV dysfunction). TD echocardiography is being used in an ever-widening group of patients to assess LV diastolic function, and current research is investigating its comparison with B-type natriuretic peptide.