Early Diastolic Tissue Doppler Imaging Research Articles

Two‐Dimensional Strain and Twist by Vector Velocity Imaging in Adolescents With Severe Obesity

The prevalence of severe obesity is increasing worldwide in adolescents. Whether it is associated with functional myocardial abnormalities remains largely unknown, potentially because of its frequent association with other cardiovascular risk factors and also use of insensitive techniques to detect subclinical changes in myocardial function. We used 2D vector velocity imaging (VVI) to investigate early changes in left ventricular (LV) myocardial function in youths with isolated severe obesity. Thirty-seven asymptomatic severely obese adolescents free of diabetes and hypertension, and 24 lean controls were enrolled. LV longitudinal, basal, and apical circumferential strain, strain rate (SR), rotations, and LV twist were measured. Obese adolescents had greater LV mass and reduced systolic and early diastolic tissue Doppler imaging (TDI) velocities than lean counterparts. L strain (-24%) and systolic and early diastolic SR were also diminished in the obese, whereas no intergroup differences existed for the circumferential deformation indexes. LV twist was more pronounced in the obese (+1.7°, P < 0.01) on account of greater apical rotation only (4.1 ± 0.9 vs. 5.2 ± 1.2°, P < 0.01), potentially compensating for the loss in longitudinal function. Systolic-diastolic coupling, an important component of early filling and diastolic function, was maintained with severe obesity. No intergroup differences were reported regarding time to peak values for all VVI indexes highlighting that dynamics of strain and twist/untwist along the cardiac cycle was preserved with severe obesity. Isolated severe obesity in adolescents, at a preclinical stage, is associated with changes in myocardial deformation and torsional mechanics that could be in part related to alterations in relaxation and contractility properties of subendocardial fibers.

Comparison of Usefulness of Tissue Doppler Imaging Versus Brain Natriuretic Peptide for Differentiation of Constrictive Pericardial Disease from Restrictive Cardiomyopathy

Brain (B-type) natriuretic peptide (BNP) and tissue Doppler imaging may distinguish restrictive cardiomyopathy (RCMP) from idiopathic constrictive pericardial disease (CP). However, their comparative efficacy is unknown for patients with CP from secondary causes (e.g., surgery or radiotherapy). We compared the efficacy of tissue Doppler imaging and BNP for differentiation of RCMP (n = 15) and CP (n = 16) were compared. BNP was higher in patients with RCMP than CP (p = 0.008), but the groups overlapped, particularly for BNP <400 pg/ml. BNP was lower with idiopathic CP than secondary CP (139 +/- 50 vs 293 +/- 69 pg/ml; p <0.001) or RCMP (139 +/- 50 vs 595 +/- 499 pg/ml; p <0.001), but not significantly different between those with secondary CP and RCMP (293 +/- 69 vs 595 +/- 499 pg/ml; p = 0.1). Patients with CP and RCMP had less overlap in early diastolic and isovolumic contraction tissue Doppler imaging velocities compared with BNP, with clear separation of groups evident with mean early diastolic annular velocities (averaged from 4 walls). Early diastolic tissue Doppler imaging velocity was superior to BNP for differentiation of CP and RCMP (area under the curve 0.97 vs 0.76, respectively; p = 0.01). In conclusion, mean early diastolic mitral annular velocity correctly distinguished CP from RCMP even when there was a large overlap of BNP between the 2 groups.