THE RELATIONSHIP BETWEEN TISSUE DOPPLER PARAMETERS AND SERIC NTPROBNP LEVELS IN PATIENTS WITH LEFT VENTRICULAR DYSFUNCTION

(r=0.73, p 900 pg/ml a fost 0.51 (sensibilitate de 82% si specificitate de 80%) cu o acurateţe de 90%. Concluzie: GMI-TDI are o corelaţie puternică cu nivelul seric al NTproBNP si poate fi utilizat cu o bună acurateţe pentru estimarea funcţiei LV. Cuvinte cheie: peptid natriuretic, indice de performanţă miocardică globală, velocitatea inelului mitral, ecocardiografie Doppler tisulară ABSTRACT Introduction: Tissue Doppler imaging (TDI) is a novel echocardiographic technique that permits measurements of mitral annular and myocardial velocities. The global myocardial index determined by the pulsed Doppler method (GMI) is a simple and noninvasive measurement for assessing global left ventricular (LV) function. This index can also be obtained by TDI (GMI-TDI). N-terminal pro-brain natriuretic peptide (NTproBNP) is recognized as a reliable marker of systolic and diastolic LV function. Aim: To assess the relationship between different TDI parameters and NTproBNP levels in patients with left ventricular dysfunction, in sinus rhythm. Material and methods: Conventional echocardiography and TDI were performed simultaneously with NTproBNP determination in 137 consecutive patients with left ventricular dysfunction, in sinus rhythm, referred for echocardiography. Patients with inadequate echocardiographic image, paced rhythm, severe mitral valvular disease, mitral prosthesis, pericardial disease, acute coronary syndrome, coronary artery by-pass within 72 hours or renal failure were excluded. The remaining 110 patients (age 63 ±13 years) formed our study group. Peak early diastolic transmitral velocity (E, using pulsed Doppler) / peak early mitral annular diastolic velocity (Ea, using TDI) ratio and the peak systolic velocity during ejection in TDI of the mitral annulus (Sa) were determined; the average of the velocities from the septal and lateral site of the mitral annulus was used. From TDI recordings, the time interval during diastole (a') and the duration of the systole Sa-wave (b') were measured. The GMI-TDI was calculated as (a' - b')/b'. GMI-TDI was measured at the septal and lateral sites of the mitral annulus, and the average was utilized. Results: Simple regression analysis demonstrated a significant linear correlation between GMI-TDI and NTproBNP (r=0.73, p 900 pg/ml was 0.51 (sensitivity of 82% and specificity of 80%) with 90% accuracy. Conclusions: GMI-TDI had a good correlation with plasma NTproBNP levels and can be used with good accuracy for the assessment of the LV function. Abbreviations: BNP = brain natriuretic peptide; E = maximal early diastolic transmitral flow velocity; Ea = maximal early mitral annular diastolic velocity; EDD = end-diastolic diameter; EF = ejection fraction; GMI-TDI = Global Myocardial Index assessed by Tissue Doppler Imaging; LA = left atrial; LV = left ventricle; NTproBNP = N-terminal pro-brain natriuretic peptide; Sa = maximal systolic velocity of mitral annulus; TDI = Tissue Doppler Imaging.