[Use of myocardial tissue Doppler imaging in cardiology]

Tissue Doppler imaging is a new promising method of non-invasive assessment of cardiac function. This method has heralded a renaissance of interest in longitudinal ventricular function. There is evidence that long-axis function is a more sensitive index of myocardial contractility than conventional echocardiographic parameters, and that therefore, this technique could contribute to early diagnosis of systolic dysfunction. Tissue Doppler imaging can be successfully applied in the assessment of regional myocardial function. It has been proven that myocardial velocities truly reflect structural myocardial changes (the degree of myocardial fibrosis) and beta-adrenoreceptor density. The use of tissue Doppler imaging in concert with stress echocardiography is also extremely encouraging and is considered as the most likely solution to the problem of quantitative analysis of stress echocardiography. The method additionally opens new horizons in non-invasive assessment of diastolic function of the heart. Myocardial velocities have been shown to have important advantages over conventional Doppler indices of left ventricular diastolic filling. Frustration among cardiologists caused by unreliability of the traditional approach in the assessment of diastolic properties of the heart seems to have been overcome. Tissue Doppler imaging allows the examination of right ventricular systolic and diastolic function, the differentiation between constrictive pericarditis and restrictive cardiomyopathy and the estimation of pressures in cardiac chambers and in the pulmonary artery. It can also establish the presence of accessory conduction pathways, the diagnosis of rejection of transplanted hearts and can be used for identification of indications for biventricular pacing. Although many clinicians believe that tissue Doppler imaging is still an experimental technique, it can now be introduced into the routine practice of echocardiographic laboratories. The wider use of the method will help to develop its benefits and better understand and overcome limitations.